RoboJackets Wiki - User contributions [en]

Materials Database

2025-02-27T07:03:25Z

Bnaing3: /* Sources */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 24.4J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air
*Important to select a supplier which gives you specifications and complies with specification codes. AR steels are not tightly regulated so the actual hardness and depth of hardening (completely through-hardened vs surface hardened) may vary by supplier.
**Technically supposed to be through hardened but many sketchier suppliers will sell AR500 that is effectively only surface hardened (up to 1/8" depth from surface according to Seth from JustCuzRobotics/BloodSport) with decreasing hardness with depth and a soft core. This doesn't matter much for thinner parts 1/4" or thinner but matters alot for thicker parts.

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

BattleBots

2025-02-12T09:04:57Z

Bnaing3:

Welcome to the '''[http://www.robojackets.org/ RoboJackets]''' BattleBots wiki! [[File:NHRL April 2024 Group Photo.JPG|thumb|right|600px|BattleBots team at NHRL April 2024]]

Everyone has seen BattleBots on T.V., fighting to the death in a gladiatorial-style arena in a shower of steel, sparks, and glory, and yet many people haven't the first clue about what it takes to build one!

RoboJackets' BattleBots team tries to solve this, by teaching members to design and build a robot 1) robust enough to take multiple beatings, but 2) strong enough to deliver its own beatings in return. A good technical challenge that takes hundreds of man-hours and buckets of love. We have built battle-ready robots in the 120 lb, 60 lb, 30 lb, 12 lb, and 3 lb weight classes, including (based on their active weapon) drum spinners, ring spinners, shell spinners, veritical and horizontal bar spinners, sumo bots, walkers, and even the occassional wedge.

We use mostly mechanical skills with some degree of electrical experience to implement our carefully CAD'ed designs, to personally manufacture the majority of our robots. Ultimately our goal is to build an awesome machine to fight one-on-one with another robot in the same weight class, all the while learning practical applications of tooling and machining, and gaining invaluable experience in the design and manufacturing process.

== Meeting Times ==

We meet in the Student Competition Center (Building on 14th Street). Wear closed-toe shoes and a t-shirt (long sleeves must be rolled up) since we will be using the machine shop. Bring a hair tie if needed. Consult the #carpool Slack channel for information regarding the time and place of the carpool. Please note that once 3 pound program members are placed on teams, that they will only meet on either Thursday OR Friday until further notice.

* Thursday: 6:30 pm to 9:30 pm
* Friday 6:30 pm to 9:30 pm

== Current Leadership ==
* Project Manager: AJ Abrigo
* The Hand: John Matthews
* The Foot: Evan Strakes
* 3lb Czar: Dylan Park
Bot Leads:
*Galaxi: Shri Thada
*Cherri: Alex King
*Graviti: Isaac Auner

== The Competition ==

The competition consists of fights between robots in the same weight class. Competition rules place certain limits on weapon design and robot weight, for a fair contest and for the safety of the observers. For instance, entanglement weapons such as ropes or nets are prohibited along with invisible weapons such as electrical interference. This focuses the robot design on aggressive weapons designed to break apart or incapacitate the other robot, and the only limit on this type of weapon is that it is well engineered so as to not harm the people around it. The presence of these aggressive weapons forces the robots to be designed to withstand large shock loads, both mechanically and electrically. The challenge of the BattleBots team is unique in that a balance needs to be reached between defensive and offensive abilities, all while ensuring that the robot is very robust in all aspects. Even a single wire or bolt coming loose will cause defeat in an intense fight!  This year we plan on attending two competitions, Motorama in Harrisburg, PA and RoboBrawl in Champaign, IL.

== 3 Pound Program ==

The three pound program is for new BattleBots members to learn the technical skills needed to succeed in BattleBots and create their very first 3 pound BattleBot. Members of this program will have the opportunity to work on a team to create a 3 pound beatleweight bot for competition. Through this process they will become proficient in Inventor CAD, machining abilities, electrical work, and teamwork. Once graduated from the 3 pound program, members can take what they've learned to the next level on a big bot team. Check out the links below for some advice on your 3 pound bot.

'''3 Pound Links'''

*[[3lbers]]
*[[3lb Beginner's Guide]]
*[[Electronics Basics]]
*[[List of 3lb Robots]]
*[https://www.riobotz.com/riobotz-combot-tutorial/ Riobotz Combot Tutorial] (400 page guide on how to build battlebots written by the pro-team that built Minotaur. A must read.)

== Competitions ==

===== 2024 =====
* [[UGA Spring Smash 2024]]
* [[NHRL April 2024]]
* [[NHRL June 2024]]
* [[RoboJackets 25th Anniversary Competition]]

===== 2023 =====
* [[NHRL March 2023]]
* [[State of Franklin Robot Rumble 2023]]
* [[NHRL June 2023]]
* [[December In House Competition 2023]]

===== 2022 =====
* [[Motorama 2022]]
* [[AVC 2022]]

===== 2021 =====
* [[2lb Competition 2021]]

===== 2020 =====
* [[Motorama 2020]]

===== 2019 =====
* [[Motorama 2019]]
* [[RoboJackets 20th Anniversary Competition]]

===== 2018 =====
* [[Motorama 2018]]
* RoboGames 2018

===== 2017 =====
* [[Motorama 2017]]
* RoboGames 2017

===== 2016 =====

*[[Motorama_2016|Motorama 2016]]
*RoboGames 2016

===== 2015 =====

*[[Motorama_2015|Motorama 2015]]
*RoboGames 2015

== Resources ==

*[http://www.robojackets.org/teams/battlebots/ RJ BattleBots Overview Page]
*[http://robogames.net/ RoboGames]
*[https://www.riobotz.com/riobotz-combot-tutorial/ Riobotz Combot Tutorial] (400 page guide on how to build battlebots written by the pro-team that built Minotaur. A must read.)
*[http://www.buildersdb.com/ Buidersdb.com]
*[[BattleBots BeetleWeight Wiki Template]]
*[[Competition Tool Packing List]]
*[[Robot Basics]]
*[[Materials Database]] (RoboJackets compiled database of common battlebot materials and their properties)
*[https://wiki.nhrl.io/wiki/index.php/NHRL NHRL Wiki]
*[https://discord.gg/nhrl NHRL Discord Server]
[[Category:BattleBots]]
*[https://www.robotcombatevents.com/ RobotCombatEvents.com] (Website to find upcoming and previous robot combat events)
*[https://docs.google.com/document/d/1Cxo2DTevGt7TUNDE0M2k8tUUlShZ6JvOY5YorWeIPb8/edit#heading=h.ugg0jyviz47c/ 3D Printing for Battlebots Guide]

Materials Database

2023-04-12T19:50:55Z

Bnaing3: /* AR500 Steel */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 24.4J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air
*Important to select a supplier which gives you specifications and complies with specification codes. AR steels are not tightly regulated so the actual hardness and depth of hardening (completely through-hardened vs surface hardened) may vary by supplier.
**Technically supposed to be through hardened but many sketchier suppliers will sell AR500 that is effectively only surface hardened (up to 1/8" depth from surface according to Seth from JustCuzRobotics/BloodSport) with decreasing hardness with depth and a soft core. This doesn't matter much for thinner parts 1/4" or thinner but matters alot for thicker parts.

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Ansys Granta Edupack (Not 54 HRC but some properties are close enough): https://drive.google.com/file/d/1aNH_X-EIR3ae4Uacl5s5DzcEWLtHAgMG/view?usp=sharing
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

Materials Database

2023-04-12T19:49:37Z

Bnaing3: /* Abrasion-Resistant (AR) Steel */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 24.4J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air
*Important to select a supplier which gives you specifications and complies with specification codes. AR steels are not tightly regulated so the actual hardness and depth of hardening (completely through-hardened vs surface hardened) may vary by supplier.
**Technically supposed to be through hardened but many sketchier suppliers will sell AR500 that is effectively only surface hardened with decreasing hardness with depth

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Ansys Granta Edupack (Not 54 HRC but some properties are close enough): https://drive.google.com/file/d/1aNH_X-EIR3ae4Uacl5s5DzcEWLtHAgMG/view?usp=sharing
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

Materials Database

2023-04-12T19:48:46Z

Bnaing3: /* AR500 Steel */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 24.4J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air
*Important to select a supplier which gives you specifications and complies with specification codes. AR steels are not tightly regulated so the actual hardness and depth of hardening (completely through-hardened vs surface hardened) may vary by supplier.

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Ansys Granta Edupack (Not 54 HRC but some properties are close enough): https://drive.google.com/file/d/1aNH_X-EIR3ae4Uacl5s5DzcEWLtHAgMG/view?usp=sharing
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

Materials Database

2023-03-05T06:06:06Z

Bnaing3: /* Abrasion-Resistant (AR) Steel */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 24.4J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Ansys Granta Edupack (Not 54 HRC but some properties are close enough): https://drive.google.com/file/d/1aNH_X-EIR3ae4Uacl5s5DzcEWLtHAgMG/view?usp=sharing
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

Materials Database

2023-03-05T06:04:29Z

Bnaing3: /* AR500 Steel */

[[File:Duck.png|right|thumb|600px|Subzero's Materials (250lber)]]
This is a brief database of useful properties for commonly used materials within battlebots as well as some background information and peoples' experience working with them. Some material properties have not been included but feel free to add anything important. Material properties usually vary slightly for a given material from vendor to vendor so in the majority of cases, trust specs given by the manufacturer or supplier over the specs in this database when they are given. In addition, some of these material properties can vary slightly depending on the data source and also other details such as heat treatment and the kind of sample the material data was acquired from.
== Steels ==
Steels are strong, dense, iron-carbon alloys which come in a variety of material compositions and treatment standards. A variety of major and minor alloying elements are added to improve certain material properties, including strength, toughness, corrosion resistance, or machinability. When selecting a grade of steel to use for your robot, consider how the material properties of the steel address the design requirements. Listed below are some more common grades of steel:

=== Abrasion-Resistant (AR) Steel ===
"AR" Steel, or "Abrasion Resistant" Steel is a high-strength, low carbon hardened alloy designed to resist wear and stress. The "grade" of the abrasion-resistant steel correlates to the Brinell hardness rating.
==== AR500 Steel ====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.29 lb/in^3
|-
| Ultimate Tensile Strength
| 225 ksi
|-
| Tensile Yield Strength
| 200 ksi
|-
| Brinell Hardness
| 450 HB
|-
| Rockwell Hardness
| C47-48
|-
| Elongation at Break
| 12%
|-
|-
| Charpy Impact (V-notch)
| 18J
|-
| Familiar Sellers
| McMaster Carr, MakeItRingTargets, Alro Steel, SendCutSend
|-
|}
Material Description:
*High strength, high hardness, abrasion resistant steel used in body armor and shooting targets
*Generally considered to be tougher than S7 tool steel but has lower hardness
*Hardened steel is very difficult to machine, is typically only used for Waterjet parts
*No further heat treatment needed
*Typically used for weapons and wedges due to it's high strength, toughness, and relatively high hardness
*Used more commonly as armor in higher weight classes
*Anecdotal experience from builders says that AR500 typically bends before it fractures
*Will rust over time when wet or exposed to air

====AR400 Steel====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

===Tool Steel===
Unlike abrasion-resistant or carbon steels, tool steels are specialized grades of steel used primarily for tool production and cutting bits.
Added alloying elements such as Cr, V, Co, W, or Mo are added to greatly increase the strength and wear resistance of the steel, but tool steels tend to be more expensive than standard carbon steels.
====S7 Tool Steel (at 54 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 30,000 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.282 lb/in^3
|-
| Ultimate Tensile Strength
| 284.9 ksi
|-
| Tensile Yield Strength
| 220.4 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 50.0 ksi-in½
|-
|-
| Calculated Toughness
| 9.42 J/in^2
|-
|-
| Charpy Impact (V-notch)
| 16.3 J
|-
| Brinell Hardness
| 543 HB
|-
| Rockwell Hardness
| C54
|-
| Elongation at Break
| 6.5%
|-
|-
| Familiar Sellers
| McMaster Carr, OnlineMetals
|-
|}
*Shock resisting tool steel that has high strength and high impact toughness
*Usually used in weapons but has been used by some NHRL builders for shafts but with hardnesses much lower than 54 HRC
*Is machined in its annealed form and then heat treated, quenched, and tempered to exactly 54 HRC which is a value recommended by the Riobotz Combot Tutorial pg 59-60.
*Ray Billings, builder of Tombstone, also endorses exactly 54 HRC for S7
*Anecdotal experience from other builders shows it fails through fracture before bending
*Considered to be less tough than AR500 and is commonly used when the higher hardness (C54 vs C48) is desired like for weapon teeth
*Extra important to avoid sharp internal corners and stress concentrations to prevent cracks from forming

===AISI Alloy Steels===
(description here)
====AISI 4340 (43 HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| 29,732 ksi
|-
|-
| Shear Modulus
| 11900 ksi
|-
|-
| Poisson's Ratio
| 0.29
|-
|-
| Density
| 0.283 lb/in^3
|-
| Ultimate Tensile Strength
| 210.0 ksi
|-
| Tensile Yield Strength
| 194.9 ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| 80.1 ksi-in½
|-
|-
| Calculated Toughness
| 24.38 J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~19 J
|-
| Brinell Hardness
| 402 HB
|-
| Rockwell Hardness
| C43
|-
| Elongation at Break
| ~9.6%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

*Ultra high strength steel that is machined in its annealed state and is heat treated by quenching and tempering it to a desired hardness.
*Riobotz's recommended hardness for shafts is 40-43 HRC which will allow it to fail by bending before breaking
*Is often used by some builders for other parts such as beaterbars at higher hardnesses
*Relatively expensive

====AISI 4140 (-- HRC)====
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Carbon Steel
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (Riobotz Sample)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact (V-notch)
| ~XX J
|-
| Brinell Hardness
| XXXX HB
|-
| Rockwell Hardness
| CXX
|-
| Elongation at Break
| ~XX%
|-
|-
| Familiar Sellers
| McMaster, Online Metals
|-
|}

==Aluminum Alloys==
[[File:AluminumParts.jpg|right|thumb|750px|Aluminum Parts]]
=== Aluminum 6061-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.33
|-
|-
| Density
| 0.0984 lb/in^3
|-
| Ultimate Tensile Strength
| 45 ksi
|-
| Tensile Yield Strength
| 39 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 26.4 ksi-in½
|-
|-
| Calculated Toughness
| 7.88 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 21.7 J
|-
| Brinell Hardness
| 93 HB
|-
| Rockwell Hardness
| B52
|-
| Elongation at Break
| 10%
|-
|-
| Machinability (Vs. 1112 Steel)
| 270%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Lightweight aluminum alloy that comes already pre-heat-treated T6 temper which gives it its strength
*Beware of tempers T4 and O which are weaker than 6061-T6
*Typically used for frame rails, plates, pulleys, and armor for some bots
*Tends to fail in bending before fracturing
*Tends to "ablate" and may take gashes when hit directly by weapons
*Easy to machine and relatively cheap

=== Aluminum 7075-T6 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| 10,000 ksi
|-
|-
| Shear Modulus
| 3800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.102 lb/in^3
|-
| Ultimate Tensile Strength
| 81 ksi
|-
| Tensile Yield Strength
| 69 ksi
|-
|-
| Fracture Toughness (T-L dir)
| 22.8 ksi-in½
|-
|-
| Calculated Toughness
| 5.87 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 5.4 J
|-
| Brinell Hardness
| 150 HB
|-
| Rockwell Hardness
| B87
|-
| Elongation at Break
| 7.9%
|-
|-
| Machinability (Vs. 1112 Steel)
| 170%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*Aerospace grade aluminum alloy which is much stronger and harder than 6061-T6
*Pre-heat-treated to T6 temper
*Past and anecdotal experience notes that it tends to fracture before it bends as it's more brittle than 6061
*Some builders recommend avoiding using it as armor or for parts that take direct hits due to fracture risk
*Relatively easy to machine
*More expensive than 6061-T6

=== Aluminum 5052-H32 ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

===Aluminum 2024-T6===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Aluminum Alloy
|-
| Modulus of Elasticity
| XX ksi
|-
|-
| Shear Modulus
| XX ksi
|-
|-
| Poisson's Ratio
| 0.XX
|-
|-
| Density
| XX lb/in^3
|-
| Ultimate Tensile Strength
| XX ksi
|-
| Tensile Yield Strength
| XX ksi
|-
|-
| Fracture Toughness (T-L dir)
| XX ksi-in½
|-
|-
| Calculated Toughness
| XX J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| XX J
|-
| Brinell Hardness
| XX HB
|-
| Rockwell Hardness
| BXX
|-
| Elongation at Break
| XX%
|-
|-
| Machinability (Vs. 1112 Steel)
| XX%
|-
| Familiar Sellers
| McMaster Carr, Midwest Steel Supply, SendCutSend
|-
|}
Material Description:
*

==Other Metal Alloys==
=== Grade 5 Titanium (Ti-6Al-4V) ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Type
| Titanium Alloy
|-
| Modulus of Elasticity
| 16510 ksi
|-
|-
| Shear Modulus
| 5800 ksi
|-
|-
| Poisson's Ratio
| 0.32
|-
|-
| Density
| 0.160 lb/in^3
|-
| Ultimate Tensile Strength
| 138-150 ksi
|-
| Tensile Yield Strength
| 128-140 ksi
|-
|-
| Fracture Toughness (Annealed Plate)
| 67.9 ksi-in½
|-
|-
| Calculated Toughness
| 31.5 J/in^2
|-
|-
| Charpy Impact Test (V-notch)
| 17 J
|-
| Brinell Hardness
| 310 HB
|-
| Rockwell Hardness
| C34
|-
| Elongation at Break
| 6.7%
|-
|-
| Machinability (Vs. 1112 Steel)
| 20%
|-
| Familiar Sellers
| McMaster Carr, SendCutSend, TMS Titanium
|-
|}
Material Description:
*Very high strength and high toughness metal alloy
*Denser than aluminum but less dense than steel. May destroy tools if you're not careful
*Typically sold and used in its annealed state for high toughness. No heat treatment needed.
*Typically used for armor, structural plates, sometimes weapons, it's pretty versatile material overall
*Known to fail in bending before failing in fracture
*Very expensive, more so than most steels and aluminum alloys
*Very difficult to machine or drill due to work hardening properties
*In some cases, outsourcing to SendCutSend might be financial preferable to buying Ti stock so discuss with your PM

==Plastics and Polymers==
Plastics and other polymerized materials are significantly less dense than metals, and are generally more machinable or formable.

===Ultra-High-Molecular-Weight-Polyethylene (UHMW)===

===High-Density-Polyethylene (HDPE)===

===Polycarbonate===

===Carbon Fiber===

===Acrylonitrile Butadiene Styrene (ABS)===

===Polylactide Plastic (PLA)===

===Thermoplastic Polyurethane (TPU)===

== Sources ==
*AR500 Steel:
**SendCutSend: https://sendcutsend.com/materials/ar500/
**Steel Warehouse: https://www.steelwarehouse.com/ar500/
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AR400 Steel:
**source

*S7 Tool Steel:
**Riobotz Combot Tutorial (Pg. 82): https://www.riobotz.com/riobotz-combot-tutorial
**Ansys Granta Edupack (Not 54 HRC but some properties are close enough): https://drive.google.com/file/d/1aNH_X-EIR3ae4Uacl5s5DzcEWLtHAgMG/view?usp=sharing
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*AISI 4340 Steel (43 HRC):
**Riobotz Combot Tutorial
**'The quantitative relationship between fracture toughness and impact toughness in high-strength steels': https://www.researchgate.net/publication/331525402_The_quantitative_relationship_between_fracture_toughness_and_impact_toughness_in_high-strength_steels

*AISI 4140 Steel:
**source

*Al 6061-T6:
**SendCutSend: https://sendcutsend.com/materials/6061-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma6061t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3850 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 7075-T6:
**SendCutSend: https://sendcutsend.com/materials/7075-aluminum/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=ma7075t6
**Machining Doctor: https://www.machiningdoctor.com/mds/?matId=3970 (Machinability)
**Team Caustic Creations: https://www.arrow.com/en/research-and-events/articles/battlebot-episode-2

*Al 5052-H32:
**source

*Al 2024-T6:
**source

*Ti-6Al-4V:
**SendCutSend: https://sendcutsend.com/materials/titanium/
**Matweb: https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=mtp641
**Machining Doctor: https://www.machiningdoctor.com/machinability/titanium/ (Machinability)

*UHMW:
**source

*HDPE:
**source

*Polycarbonate:
**source

*Carbon Fiber:
**source

*ABS:
**source

*PLA:
**source

*TPU:
**source

== Notes ==
*The charpy impact data provided by Team Caustic Creations was "quick and dirty" and was hard to verify
**They didn't specify how they got the data and where from
**Their value for Ti-6Al-4V was off from the Matweb data page so take it with a grain of salt
**Charpy impact data is pretty hard to find. It might be worth it for RoboJackets to our own Charpy impact tests

*The Plastics and Polymers section does not distinguish the material property differences between machined stock pieces and extruded 3D prints. Because of the layer-by-layer extrusion of 3D printers, it is vital to note that the material strength is directionally dependent, and depends on the infill style and percentage infill.

Binari

2022-12-28T08:45:55Z

Bnaing3:

[[File:Binari_IRL.jpg|500px|thumb|right]]

== Introduction ==
As you may know, we in Robojackets have a few rules that are strictly enforced: use safe shop practices, all robots name must end in "i", and NO WEDGES (no exceptions). After all, the weapon system is what makes a battlebot fun to design, build and watch. This being the case, 2 (two) weapons should be even better...Right? And so the motivation for this bot was to create a 2 weapon battlebot, specifically a double horizontal spinner. This would function as sort of a test bed to 1. evaluate the feasibility of employing 2 weapon systems in this weight class and 2. determine how effective a second weapon would be in combat.

Members:
*George 'Knute' Broady (Lead)
*Paul Matesevac
*Lucy Bricker
*James Peavy
*Joe Irwin
*Mannan Goel

[[File:Binari_TeamPhoto.jpeg|480x360px|Binari Team Photo]]

== Drive System ==
We decided to employ a shuffler drive system in order to take advantage of the 50% weight bonus granted by most (not all) competitions. This would allow us to make a double horizontal without gimping the weapons too much. The shuffler was a 4 foot assembly with holes drilled at 90 degree rotations along the length of the shafts. These holes would accept dowels which would then hold the semicircular cams. All of this would rotate inside ball bearings in the shuffle feet. Further, the feet were made taller than the chassis in order to allow for invertibility.

Notes and Lessons:
*This system requires pretty careful machining and assembly. Misalignment and burs will cause jamming. Our problems were exacerbated by excessive waterjet taper on the cams, which can be partially resolved by reducing the machine-ability settings in the jet and then filing to fit.
*Ensure there is a collet for your shaft size and a machinists jack, as DIY solutions lead to inconsistencies.
*Provide ample protection for the shuffle system in your design. This drive system, while it can be as effective as wheels, is not as robust. Bent shafts, shifted plates, loose bearings can cause it all to fall apart and render you immobile after a big hit.
*consider designing the shuffler as modules, which can be swapped between matches. We made the mistake of basically locking the shufflers in with the rest our our chassis and essentially had to take the whole bot apart to unbend the drive shafts after a fight.

=== Foot Profile ===
[[File:Binari_Foot.png|400px]]

=== Cams and Bearings ===
[[File:Binari_ShuffleDecon.png|400px]]
[[File:Binari_ShuffleBottom.png|400px]]
[[File:Binari_Cam.png|400px]]

=== Drive Gears ===
[[File:Binari_DriveGear.png|400px]]

== Weapon System ==

===Design Considerations===
Because we had 2 weapons, it was important to have them be light enough as to not surpass a combined weight of ~15 lbs. The extra weight bonus from the shuffler allowed for this to be much more feasible (also required because we have 2x the weapon motors).

===Weapon Design===

Overall Design: Made to resemble Valkyri's overall weapon stack, minor changes were made to the overall design, A roller bearing (in design) was not needed at the bottom because of the constraint on the shaft itself (enough distance to spin without touching the bottom plate). This did not work, therefore a needle roller bearing should always be strongly considered in future live-shaft designs despite clearance looking good enough.

Weapon: Our weapons were waterjet out of AR500 steel (made from sheets of gun target steel). Each weapon was 0.5 inches in thickness and 11 inches in diameter. The overall shape was intended to put as much mass at the hitting ends as possible, there was no need to save weight therefore we were able to have a solid weapon. There was added structural support around the location that met with our weapon shaft, this was to theoretically prevent any snapping of the weapon (fears due to Apachi's weapon failure). Additionally, the weapon's geometry was made in order to ensure that at the maximum distance, only 1 point has the possibility of hitting (in order to reduce the chance of us 'skimming' the other bot instead of properly hitting it).

Belt Protection: Carbon fiber reinforced nylon material called Onyx, printed on a Markforged 3D printer. The print was not the best, therefore our belt protection was pretty non-existent. Also, the material may not have been a good choice, as carbon fiber doesn't resist instantaneous hits very well.

Lessons:
*Do not use our classical belts, use industrial/automotive belts instead
**Opinionated Note: Perhaps putting the belts directly onto the motor is not best practice... utilizing the shaft to attach a small pulley would allow for both timing belt usage and advantageous gear ratios. At the very least, do not place belts directly on grooved motor housings-make sure the can is smooth.
*For under/over cutters, ensure that your weapon is constrained vertically so that if it is flipped, the weapon-shaft combination doesn't fall onto the top/bottom plate and rub against it
**Alternatively, make room between the weapon and the top/bottom plate for a needle thrust roller bearing
*Look for better protection for belts/weapon stacks (testing materials/more research)
*AR500 is sorta hard to machine (we need to basically increase the waterjet thickness, machinability, and possibly do 2 passes)
*A positive was that the weapon shafts displayed no significant bending or deformation after competition on inspection. Shafts were 3/4" Diameter 1144 Carbon Steel shafts with a yield strength of 100,000psi. May be used as a reference for future calculations. McMaster link here: https://www.mcmaster.com/6101N55/

===Weapon Stack and Weapon Pictures===

[[File:Binari_WeaponStack.png]]

== Chassis System ==
*The chassis is composed almost entirely of .25" 6061 Aluminum
*It was made with the robojackets standard puzzle fitting plates method
*shufflers were mounted between inner and out side plates
*front and back plates spanned all the way across the bot.
*Large blocks of HDPE were added last minute to the sides to prevent direct hits to shuffle shafts

Lessons and Notes:
*Aluminum should only be used as a skeleton for a battlebot. 6061 is not sufficient to take hits at the 30lb level- armor should really be Titanium or AR500 steel.
*The puzzle fit method is perfectly fine for meshing plates together however the rectangular prism geometry is dated and vulnerable.
**consider geometries better suited to deflecting hits or limiting the impact of eventual deformation from combat

== Electronics ==
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| Turnigy Aerodrive SK3 - 5055-280KV Brushless Outrunner Motor
 
|-
| Drive Motor Controllers
| Mini FSESC4.20 50A base on VESC® 4.12 with Aluminum Anodized Heat Sink
|-
| Weapon Motor
| Scorpion HKIV-4035-520KV
|-
| Weapon Motor Controllers
| YEP 100A (2~6S) SBEC Brushless Speed Controller
|-
| Receiver
| FlySky FS-iA6B 
|-
| Transmitter
| FlySky FS-i6X 
|-
| Battery
| Lectron Pro 22.2V 6500mAh 100C Lipo Battery
|-
|}

In broad overview, our electronics system was as follows. It was originally meant to include four LiPo batteries, but this was scrapped within the last two weeks of competition in favor of one single 22.2V 6500mAh 100C LiPo. Connections were made via Wet Noodle wire, XT60 clips, and screw terminals. Electricity flows from the battery into one terminal of the Team Whyachi switch. The other terminal receives the connections from all the positive ends of each piece of electronic equipment in the bot (the ESCs, which are connected to the motors via bullet connectors). All negative paths go to ground.

Despite past lessons, electronics were a struggle on this bot. One main issue is that when an ESC says "Reversible" this does not necessarily mean that it has a bidirectional mode, which is needed for drive motors. Rather, it may mean that it can be set to reverse the output without removing any wires (not very useful for us). For example, YEP 100 A ESC are NOT reversible, and Red Brick 100 A esc are also NOT reversible. From our understanding, using am ESC that supports BLHeli or VESC firmware guarantees that it is able to function in bidirectional mode.

There was also a bit of a concern for our original plan to use multiple batteries in parallel. From other experienced builders, this was later found not to be a large issue. However, it makes wiring and other elements more difficult.

The current draw calculations for the shufflers from the Apachi spreadsheet do not seem accurate. Both Chonkii and Binari require much less power than that sheet would suggest. It is still very difficult to know how much capacity and current is needed for a shuffler system without testing.

The weapon motors and ESCs seemed to function well, however the belts snapping preventing and substantial use. As mentioned above, automotive timing belts should be used in the future.

IMPORTANT LESSON (and what should be M.O. of the club):
* Do not leave electronics to the end of the year. Make wooden mockups of the bot at the very beginning of the year so that wiring can be measured and soldering done. This mockup could even be driven. This is another opinion: chassis is less important than the ability to have consistently performing drive and weapon systems, which should be perfected year-to-year and driver control can be optimized.

== Competitions ==

=== [[AVC_2022|AVC 2022]] ===

*Results: 0-2
**Bracket Style: Double Elimination
***[Binari (loser) V.S. Crippling Depression (winner): https://youtu.be/npJXu5YIfbU]
**** Crippling Depression was a wedge and undercutter combination bot.
**** As an undercutter, the weapon went underneath ours, slightly sheared one of our bolts
**** After getting flipped, they absolutely destroyed the weapon guards and side armor and bent our shuffler system and front plate
**** Lost via tap-out
***[Binari (loser) V.S. HUHMWPE DUHMWPE (winner): https://youtu.be/zIZz2qR4AVM]
**** Ripped off sideplate, and the shuffler system slowly fell apart
**** Lost via tap-out
**** More Description

==== Issues ====

* One of the largest problems we encountered this year was the ridiculous amount of taper from the waterjet. Even with designing for added tolerance, plates did not fit together and holes were too small resulting in a lot of time spent re-machining. This probably isn't going away any time soon since it is doubtful the SCC will shell out the money for a new one so it is good to be aware of this and even to perform test cuts to evaluate how your part might end up.
* We added pulley guards to our bot with the intention of, well, guarding the pulley. These were 3-D printed in the AE makerspace on a markforged printed out of the carbon fiber reinforced nylon material onyx. This was not the super material we were led to believe it was. Frankly, it sucked. The prints we ended up using experienced bed adhesion issues during print but due to time constraints (late redesign, long time to get someone to print it in AE space) we had to go with them. The infill resembled stacks of pellets. This may or may not be a result of the bed adhesion issues but it was shredded immediately. These ended up being more trouble then they were worth so alternative methods of keeping pulleys safe should be considered.
[[File:Binari_BadPrint.jpg|400px]]

* Independent of the pulley guards getting shredded, the belts were shredded as well. As it turns out, the polyurethane belts do not hold up, especially when placed directly on a ridged scorpion motor can. Consider using high strength belts such as those with cords inside.
[[File:Binari_BadBelt.jpg|400px]]

* Considerations for armor were not made initially resulting in large HDPE blacks being bolted to the side last minute. When these blocks took a direct hit to the front the shifted an entire side of the bot, bending the front plate and one of the drive shafts and knocking bearings out of place. I can't stress this enough; have a plan for your armor.
[[File:Binari_HDPE.jpg|400px]]

* 1/4" 6061 Aluminum did not end up being as resilient as previously thought. Once the HDPE blocks were ripped off, the side plates soon followed nd large deformations were observed after fights. So make sure your properly defend your bot.
[[File:Binari_Bent.jpg|400px]]
[[File:Binari_Destroyed.jpg|400px]]

* Someone, preferably everyone needs to learn how ESCs work. We bought "reversible" ESCs for our drive since, in previous years, I've been on teams which have made the mistake of not getting reversible ones resulting in only 1 drive direction. But apparently "reversible" doesn't necessarily mean the ESC can drive both directions???????? Upon finding this out, (again late) we scrounged Hocki's ESCs but they were painfully slow and we would've needed to do some Arduino garbage to try and fix that which no one was qualified to do. So we replaced those with red bricks chonkii had selected for their drive but turns out those weren't reversible either. Luckily everyone at AVC is way nicer than they need to be and several people brought ESCs for us day 2 and someone sat there and programmed them for us. These situations need to be avoided.

==== Changes to make ====

* Put pulley over motor can or use flat can motor
* Apply more deliberate shuffler protection. This may involve a full chassis redesign, including a plan for armoring the bot.
* Use functional motor ESC combinations and spec batteries properly.
* If possible, lower bot. The over cutter was useless in both matches since both opponents were fully beneath it. When crippling depression was flipped though, its under-then-over cutter was perfectly positioned to tear through out pulley guards and rip apart our weapon stack up.
* Use standard size bearings and belts and design around these as this will allow for ordering plenty of spares.
* Speaking of spares, make them. Re-bending plates back into place isn't fun. Instead it's better to be able to hot swap between matches.
* To expand on this, designs with modularity have a lot of merit. If the shuffle shaft/plates get damaged for example, being able to replace the whole shuffle module will be very helpful.
* Avoid locking things that need servicing into the bot. You don't want to have to remove multiple plates to access 1 thing.
==== Related Files ====
* Bill of Materials: https://docs.google.com/spreadsheets/d/1Z-RYOTp5Wkwx8Lf1MlFdWmMpdz6BR6DFc4hk9f5zwyg/edit?usp=sharing

[[Category: BattleBots]]
[[Category: FeatherWeights]]
[[Category: BigBots]]

Materials Database

2022-12-26T09:08:18Z