RoboJackets Wiki - User contributions [en]

Anarchi

2022-06-15T02:13:49Z

Ctyler31:

[[File:Anarchi_1.jpg|right|thumb|600px|Fully Constructed Anarchi]]
== Introduction ==
Anarchi was supposed to be an experimental 30lb bot where it's primary weapon could be switched between a horizontal spinner and a drum spinner via weapon modules that would be held by the chassis using a modular interface. Unfortunately, due to the poor member retention throughout the semester, the team was unable to manufacture the drum spinner module and was only able to finish the horizontal spinner module before competing in AVC 2022.

Members:
*Dylan Adriano (Bot Lead)
*Brian Naing
*Cade Tyler
*Jackson Isenberg
*Lucas Luwa

== Chassis ==

=== Main Chassis ===

=== Modular Interface ===

The modular interface is the crux of the modular robot design. The interface was designed for the ability to slide the weapon module into the center of the robot and then attach it using bolts into threaded holes. Through this universal interfacing design, any weapon module following this interface could slide into the chassis. A benefit of this design is that is relatively simple and only requires that very simple attachment mechanism to fit any weapon module so long as it follows the universal interface design. This was (supposed to be) Anarchi's major selling point -- that the robot could work with any weapon design.

[[File:AnarchiChassisModularInterface.png|center|thumb|600px|View of the Modular Interface]]

The main problem with the interface is the fact that it requires very precise manufacturing to maintain assembly strength and allow for the weapon module to be inserted and removed easily. This became a very difficult engineering challenge, especially since we did not properly consider tolerances when designing the chassis. As a result, we had to file down the puzzle fits and interface sides in order to even fit the pieces together.

Another problem was that the interface did not consider factors such as center of mass or weapon height, which was especially troublesome when we wanted to try designing a vertical spinner. The interface was not well equipped to handle major changes in the center of mass of the robot and therefore limited what kinds of weapon were viable for the interface.

=== Horizontal Spinner Weapon Module ===

=== Drum Spinner Module (Never Started) ===

== Drive System ==
=== Overview ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Wheels
| Colson Performa wheels https://www.vexrobotics.com/775pro.html
|-
| Gearbox
| VersaPlanetary 10:1 gearboxes https://www.vexrobotics.com/versaplanetary.html
|}

The drive system consisted of four wheels, two on each side. The back wheels were directly driven and the front wheels were connected to the back wheels with timing belts and pulleys. The drive motor shafts, wheel hubs, and driveshafts were all hexagonal. The back wheels were mounted directly on the drive motor shaft. To constrain the wheels axially, the CAD of a timing pulley was “borrowed” from McMaster and edited such that a shoulder pressed against a bearing in the outer side plate. That bearing was pressed into a pocket so it could not slide.

The front wheels were assembled in the following way:
Inner bearing cover – Flanged bearing – Retaining ring – Wheel – Timing pulley – Retaining ring – Flanged bearing

The inner bearing covers were 3D printed parts protecting electronics from spinning things. The flanged bearings were pressed into the inner and outer side plates. The rest of the items were put on the drive shaft and sandwiched between the bearings to constrain everything axially. For both the front and back timing pulleys, 6-32 bolts were used to hold the timing pulleys to the wheels. Both the front and back timing pulleys were printed out of ABS. PLA copies as backup were also printed last minute. The timing pulleys did not break during any of the fights (aside from a small extrusion which did not affect how they functioned).

=== Issues ===
A lot :(

Below are issues roughly ranked from most severe (#1) to least severe (#7)

1. Motor shaft slipping within gearbox interface. There were a few causes. First, Vex gearboxes are not designed for combat robotics and appear to be designed to slip at a certain torque to prevent damage. Second, a key didn’t fit in the gearbox during assembly. Due to a lack of time, the short term solution was to ignore it and if it was a problem later to fix it (spoiler: It was a problem later).

2. The modular bot was in fact not very modular. After the severe lack of drive was noticed after the 2nd fight at AVC the plan was to finally address the issue. However, access to the gearbox required nearly the entire boat to be disassembled and there was not time. Make important subassemblies fast to remove to fix or replace.

3. Retaining ring grooves in hexagonal shafts should be avoided for a number of reasons. Retaining rings are designed for specific grooves with tolerances (check manufacturer’s catalog) that are tricky to achieve in a non circular shaft. So machining them can be difficult and result in inaccurate grooves. The rings also plastically deform if they are stretched just a little past the shaft they are designed for. During competition only a single retaining ring ended up going on each shaft.

4. Brushless motors appear to be much more common in BattleBots (for both drive and weapon). Do your research.

5. The back and front wheels are connected by a timing belt. Initial calculations were off and the belt ended up being too loose. Here were different efforts taken to solve the issue:
A. Printing the next larger timing pulley on McMaster (slightly too large)
B. Creating and printing a custom timing pulley with one more tooth than the configuration that was too loose. This was barely too tight and the drive couldn’t be assembled.
C. Solution that ended up being used: creating two idlers with bushings for each side. They were able to be mounted in the outer side plate without any changes
Better solutions:
A. Do better math in the start
B. Have some way to tension the belt in case the math is off or the belt lengthens over time
C. Do things less last minute and have time to purchase another belt
D. Avoid belts and use chains or gears. Although each method of power transmission potentially has issues

6. The center of mass was slightly in front of the front wheels instead of in between the front/back wheels. This turned out to not really be an issue. At least as far as we could tell for the short amount of time it could drive.

7. The Drive ESC was way over-specced. Both current wise and had random features like regenerative braking. Although it did work fine, purchasing a more suitable ESC is probably better.

TL;DR
Drive is important - do your research and figure out what works

== Weapon Systems ==
=== Horizontal Spinner Module ===
[[File:AnarchiHorizontalSpinnerWeaponModule1.png|center|thumb|600px|Picture of entire weapon module.]]

Anarchi's horizontal spinner weapon module frame consisted of 1/4" Aluminum 7075 Plates that were fastened together via 1/2" long 5-40 screws and weighed approximately 4lbs.The compartment for the weapon module was way too narrow resulting in the U-shape that was needed to give clearance to the belt as it spread outwards from the motor. In compartment ended up still being way too narrow as the belt would contact the edges as it spun up, causing some belt grinding and orange dust to form. The other "cat-shaped" hole behind it was a hole for the weapon ESC bullet connectors to come through to connect to the weapon motor bullet connectors.

[[File:AnarchiHorizontalSpinnerWeaponModule2.png|center|thumb|600px|Sideview of Weapon Module]]

The module was designed to interface with the chassis and screw in at multiple strengths due to the worry of the weapon module being ripped out. The plates were also held together by the 1/2" diameter shoulder bolt and locknut that held the weapon assembly in place.

The weapon motor was mounted and bolted down on straight slots that allowed the motor to be pulled back to adjust the belt tension.

[[File:AnarchiHorizontalSpinnerWeaponModule3.png|center|thumb|600px|Bottom View of Weapon Module]]

A midpoint for the slots was arbitrarily chosen and then a nominal cad representation of the belt from the motor from the midpoint of the slots and the weapon pulley was made. The outer circumference of the CAD-ed belt was then used to determine what outer circumference length belt to order from McMaster with the assumption that the belt could be pulled back enough to reach the right amount of tension. It suffered from alot of issues and points of improvement:

*The slots did not go far enough back as the polyurethane belt permanently stretched over the course of the matches, resulting in us having less than ideal belt tension and a weaker weapon in our third match even when our motor was pulled all the way back.
*Better means to calculate the belt length and longer tensioning slots should be pursued.
*Serpentine belts should also be considered over polyurethane belts as they seem to be stronger, of higher quality, and less prone to stretching.
*Another issue with straight slots was that a good hit could potentially loosen the weapon motor mounting bolts and cause the motor to be pulled forward and killing the belt tension so alternate tensioning slot geometries or methods should be considered.
*With the way our bot was hard to reach into or take apart, we had to pull the motor back by the screws which was difficult and likely caused us to not hit the right amount of tension we should have due to lack of grip strength. The bot should be designed so that the motor can be grabbed by the can and pulled back to tension the weapon belt.

=== Horizontal Spinner Weapon Bar ===

[[File:AnarchiHorizontalSpinnerWeapon1.png|center|thumb|600px|Horziontal SpinnerWeapon in CAD]]

====Design:====

Anarchi's horizontal spinner module utilized an asymmetrical style weapon with a longer impactor end and a wide counterweight to keep the center of mass along the axis of rotation, causing it to resemble a hammer. However, the impactor design was not made with a specific rake angle in mind but it was later measured to be 3.1 degrees. relief angle was also not considered in the design and was 0 degrees which may or may not be ideal. The weapon was made asymmetrical as it would increase the average bite (weapon insertion distance into opponent) by a factor of 2, improving the energy transfer to the opponent upon impact. the weapon It was 0.5" thick and made of AR500 steel which is considered one of the best materials for weapons that can be made via the waterjet. It weighed 4.509lbs and had an MOI (moment of inertia) of 74.825lb*in^2.The impactor ends were designed to sharp as they were intended to bite into opponents' armor better however its effectiveness didn't get the chance to be properly proven. It is constrained via 8 3/8-16 bolts that fasten it securely onto the pulley. The holes are "close fit" clearance holes (you can select a "close" option using hole wizard in Inventor) and in theory would allow a good bit of play if it weren't for the waterjet taper making the holes slightly smaller in reality. If you plan on trying to waterjet AR500 with closer fit clearance holes, it is essential that you do test cuts beforehand because AR500 is extremely difficult to machine. The hole in the middle is an inch long in diameter and was meant to allow a generous amount of clearance between the stationary spacers and the spinning steel weapon. Below is a useful pic of some basic dimensions.

[[File:AnarchiHorizontalSpinnerWeapon2.png|center|thumb|600px|Useful dimensions of weapon. Check CAD file for further details]]

====Analysis:====

WARNING: The following analysis was not conducted by an FEA expert so please be aware that the approach may be inaccurate and/or incorrect so be very skeptical.
[[File:AnarchiHorizontalSpinnerWeapon3.png|center|thumb|600px|Attempt at FEA Analysis on the weapon. Take this analysis with a bucket of salt]]

Rudimentary FEA was also conducted with an arbitrarily large load applied to a corner edge of the impactor and the weapon being constrained via 8 dowel pin parts where the contacts/constraints for the weapon were applied to simulate the bolts. It was found that the greatest stress occurred along the curvature between the central outer diameter and the length of the impactor similar to a cantilever beam with a constant end load. It was found that the greater the value of the curvature radius, the lower the max stress. An interesting thing to note is that the reaction forces on the contacts were calculated to be the greatest on the two rightmost bolts, 2nd greatest on the two bolts immediately to the left of them, and lowest on the bolts to the left of the center. This lead to the assumption that it was imperative to make the bolts be as large as reasonable to minimize the shear stress on the individual bolts to minimize the chances of the first two bolts on the right of the center failing. 3/8-16 bolts were selected due to the fact that they were the largest reasonable sized hole we could fit within the given geometry and that we already had taps for them in the shop.

A key element of designing an asymmetrical weapon is making sure the non impactor side won't be making contact with the opponent before the impactor does. The theory of bite is discussed in detail starting on page. 158 of the Riobotz Combot Tutorial. Our calculations, as linked below, assumed that the robot driving velocity would be 16.7mph and that the max rpm would be around 6528rpm. These values were produced by the Team Just'Cuz Robotics drivetrain calculator and the runAmok Spin-up calculator and as a result, both are not very accurate to real life (both better theoretical and validated models need to be developed). Based on the bite equation presented on page 158, our dmax was calculated to be 2.574803 inches with the average bite being 1.2874015 inches. Where our calculations differ from the Riobotz Combot Tutorial is that we check to make sure that the minimum distance at the point in the rotation where the weapon counterweight starts to pull away from the opponent is greater than zero to ensure that contact won't be made as this is the closest they will be to each other. We just made sure that this distance was greater than 0 since we knew the drive was going to be slower but it would be recommended to use some sort of safety factor for this in the future.
====Manufacturing:====

The weapon was waterjetted out of an approximately 0.5" thick AR500 steel shooting target from makeittargets.com. Make it ring targets don't have a super tight tolerance on their plate thicknesses as ours measured around 0.491" thick. The settings used on the waterjet cut are listed below and yielded very satisfactory results given the weapon didn't need to hit any tight tolerances unlike the press fit D-shape that Binari's weapon needed. In addition, most of the contours were cut on quality 3 while the clearance holes were cut at quality 5 since they would have to interface closely with the bolts. It's recommended to cut the "teeth" contours at a higher quality. The cut took approximately 58 minutes but we had no issues with it. The overall geometry came out nicely and the weapon was well balanced with no perceptible vibrations in the bot upon spinning up. The weapon was sandblasted to get rid of rust and mill scale which resulted in a clean, matte finnish.

Waterjet OMAX Make Cut Settings:

Material: Tool Steel D2 (RC 60)

Machinability: 54.08 (Metal)

Thickness: 0.55in

Tool Offset: 0.0125 inches

====Performance:====
*Weapon was very well balanced when spinning up.
*Due to drive not working well, anarchi's weapon was never able to achieve it's maximum possible bite, and therefore a really good hit, in its matches
*Waterjet taper made the holes slightly smaller than in CAD, resulting in little play, keeping the weapon pretty axially-symmetric with the pulley
*Sharp edges of impactor teeth started blunting slightly after the first two matches although this did not seem to off-balance the weapon any noticeable amount.
*Overall geometry of the weapon held up very well and no perceptible deformation was observed in the overall shape.
*Due to the ratio of bot wideness to weapon length, the area of protection/attack given by the weapon in the front of the bot was smaller than counterparts such as BEAM. Consider increasing weapon diameter or reducing bot width.
*The 8 3/8-16 bolts could possibly be overkill as some other horizontal spinners like BEAM have used configurations with slightly smaller and fewer bolts.
*Design wasn't made with a specific rake angle or relief angle in mind. The greater the rake angle, the better the weapon will be at biting into the opponent and transferring energy at the cost of blunting faster. If the rake angle is too large, it can make the teeth more fragile.
*A member from Hypershock recommends that the impactor side of weapons like that be flat on the end in order to prevent the insertion edge from prying itself out of an enemy bot's armor.
*Advantage of having weapon weapon being symmetric around the line between the impactor and counterweight is that you have two impactor teeth instead of just one meaning you can flip it around in case one of the teeth gets too blunted which would be a bigger problem given a larger rake angle. Issue is that you can't implement a large relief angle if you do that so it's a tradeoff. Relief angles also make the teeth weaker.
*Weapon was relatively light (under 20% of total weight) due to modular interface taking up weight. Will have hit harder if bigger. Many bots do between 20-33% of total weight.

=== Horizontal Spinner Weapon Assembly ===

== Electronics ==
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| Vex 775 pro (brushed 12V motors)
 
|-
| Drive Motor Controllers
| Sabertooth Dual 25A 6V-24V Regenerative Motor Driver
|-
| Weapon Motor
| Horizontal: Scorpion SII-4035-250KV, Drum: HKIV-4025-1100KV
|-
| Weapon Motor Controllers
| HobbyWing Platinum PRO V4 120A ESC
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Zeee 22.2V 60C 4000mAh 6S Lipo Battery

|-
|}

== Competitions ==

=== [[AVC|AVC]] ===

*Results: 1-2
**Bracket Style: Double Elimination
***[Anarchi (loser) V.S. Wedgeham (loser): YouTube Link]
**** Match started with Wedgeham overwhelming Anarchi with it's superior driving by raming into us and pushing us into the wall repeatedly
**** Anarchi never tried to spin it's weapon up to maximum velocity due to the fear of self damage.
**** Anarchi landed a few small hits on wedgeham but none enough to do any significant damage due to the weapon not being able to reach it's max velocity
**** Half-way through the match, the gear boxes got internally damaged, slowing down our drive and our ability to move
**** When time hit 3 minutes, Wedgeham was the decided winner due to it being able to prevent us from spinning up or moving properly
**** After the match, it was determined that the left drive motor would no longer spin the drive wheel when above 60% throttle
**** We were unable to repair the gearboxes as the bot would have to be mostly disassembled in order to access them. The issue likely could've been solved if we had been able to easily open up the gearboxes
***[Anarchi (winner) V.S. Dragon Fruit (loser): YouTube Link]
**** Drive was much slower and harder to control. Had to slowly move anarchi towards the opponent
**** DragonFruit had a spinning active weapon and drive but seemed to also have some slight driving issues
**** Weapon was able to spin up to a high enough speed to rip off DragonFruit's wheel resulting in them tapping out.
**** After this match, orange powder from the polyurethane flat belts grinding against the inner side plate had formed and the bearings didn't spin as cleanly as previously (they felt slightly crunchier)
**** Weapon had suffered a small amount of blunting around the edges that made impact.
***[Anarchi (loser) V.S. Crippling Depression (winner): YouTube Link]
**** Drive had almost completely failed. Anarchi was unable to fully drive to the starting zone
**** Crippling depression fought in overcutter mode to likely avoid unnessecary damage to itself as Robert Cowan knew our drive was no longer working and he had matches left
**** Weapon was unable to spin up to a sufficient speed due to Crippling Depression's constant ramming. Crippling depression kept ramming us until our drive would not work at all.
**** More orange powder had formed and the weapon bearings now felt significantly more crunchy and spun less smoothly. In a perfect world, they should've been replaced before this match.

==== Issues ====

* Stuff
* Other Stuff

==== Changes to make ====

* Stuff
* Other Stuff

== Trivia ==
*The Vectrax was rendered inoperable twice by Chonki members (mainly Brian) during its construction.
[[Category: BattleBots]]
[[Category: FeatherWeights]]
[[Category: BigBots]]

Anarchi

2022-06-15T02:11:34Z

Ctyler31: drive stuff

[[File:Anarchi_1.jpg|right|thumb|600px|Fully Constructed Anarchi]]
== Introduction ==
Anarchi was supposed to be an experimental 30lb bot where it's primary weapon could be switched between a horizontal spinner and a drum spinner via weapon modules that would be held by the chassis using a modular interface. Unfortunately, due to the poor member retention throughout the semester, the team was unable to manufacture the drum spinner module and was only able to finish the horizontal spinner module before competing in AVC 2022.

Members:
*Dylan Adriano (Bot Lead)
*Brian Naing
*Cade Tyler
*Jackson Isenberg
*Lucas Luwa

== Chassis ==

=== Main Chassis ===

=== Modular Interface ===

The modular interface is the crux of the modular robot design. The interface was designed for the ability to slide the weapon module into the center of the robot and then attach it using bolts into threaded holes. Through this universal interfacing design, any weapon module following this interface could slide into the chassis. A benefit of this design is that is relatively simple and only requires that very simple attachment mechanism to fit any weapon module so long as it follows the universal interface design. This was (supposed to be) Anarchi's major selling point -- that the robot could work with any weapon design.

[[File:AnarchiChassisModularInterface.png|center|thumb|600px|View of the Modular Interface]]

The main problem with the interface is the fact that it requires very precise manufacturing to maintain assembly strength and allow for the weapon module to be inserted and removed easily. This became a very difficult engineering challenge, especially since we did not properly consider tolerances when designing the chassis. As a result, we had to file down the puzzle fits and interface sides in order to even fit the pieces together.

Another problem was that the interface did not consider factors such as center of mass or weapon height, which was especially troublesome when we wanted to try designing a vertical spinner. The interface was not well equipped to handle major changes in the center of mass of the robot and therefore limited what kinds of weapon were viable for the interface.

=== Horizontal Spinner Weapon Module ===

=== Drum Spinner Module (Never Started) ===

== Drive System ==
=== Overview ===
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Wheels
| Colson Performa wheels https://www.vexrobotics.com/775pro.html
|-
| Gearbox
| VersaPlanetary 10:1 gearboxes https://www.vexrobotics.com/versaplanetary.html
|}

The drive system consisted of four wheels, two on each side. The back wheels were directly driven and the front wheels were connected to the back wheels with timing belts and pulleys. The drive motor shafts, wheel hubs, and driveshafts were all hexagonal. The back wheels were mounted directly on the drive motor shaft. To constrain the wheels axially, the CAD of a timing pulley was “borrowed” from McMaster and edited such that a shoulder pressed against a bearing in the outer side plate. That bearing was pressed into a pocket so it could not slide.

The front wheels were assembled in the following way:
Inner bearing cover – Flanged bearing – Retaining ring – Wheel – Timing pulley – Retaining ring – Flanged bearing

The inner bearing covers were 3D printed parts protecting electronics from spinning things. The flanged bearings were pressed into the inner and outer side plates. The rest of the items were put on the drive shaft and sandwiched between the bearings to constrain everything axially. For both the front and back timing pulleys, 6-32 bolts were used to hold the timing pulleys to the wheels. Both the front and back timing pulleys were printed out of ABS. PLA copies as backup were also printed last minute. The timing pulleys did not break during any of the fights (aside from a small extrusion which did not affect how they functioned).

=== Issues ===
A lot :(

Below are issues roughly ranked from most severe (#1) to least severe (#6)

1. Motor shaft slipping within gearbox interface. There were a few causes. First, Vex gearboxes are not designed for combat robotics and appear to be designed to slip at a certain torque to prevent damage. Second, a key didn’t fit in the gearbox during assembly. Due to a lack of time, the short term solution was to ignore it and if it was a problem later to fix it (spoiler: It was a problem later).

2. The modular bot was in fact not very modular. After the severe lack of drive was noticed after the 2nd fight at AVC the plan was to finally address the issue. However, access to the gearbox required nearly the entire boat to be disassembled and there was not time. Make important subassemblies fast to remove to fix or replace.

3. Retaining ring grooves in hexagonal shafts should be avoided for a number of reasons. Retaining rings are designed for specific grooves with tolerances (check manufacturer’s catalog) that are tricky to achieve in a non circular shaft. So machining them can be difficult and result in inaccurate grooves. The rings also plastically deform if they are stretched just a little past the shaft they are designed for. During competition only a single retaining ring ended up going on each shaft.

4. Brushless motors appear to be much more common in BattleBots (for both drive and weapon). Do your research.

5. The back and front wheels are connected by a timing belt. Initial calculations were off and the belt ended up being too loose. Here were different efforts taken to solve the issue:
A. Printing the next larger timing pulley on McMaster (slightly too large)
B. Creating and printing a custom timing pulley with one more tooth than the configuration that was too loose. This was barely too tight and the drive couldn’t be assembled.
C. Solution that ended up being used: creating two idlers with bushings for each side. They were able to be mounted in the outer side plate without any changes
Better solutions:
A. Do better math in the start
B. Have some way to tension the belt in case the math is off or the belt lengthens over time
C. Do things less last minute and have time to purchase another belt
D. Avoid belts and use chains or gears. Although each method of power transmission potentially has issues

6. The center of mass was slightly in front of the front wheels instead of in between the front/back wheels. This turned out to not really be an issue. At least as far as we could tell for the short amount of time it could drive.

7. The Drive ESC was way over-specced. Both current wise and had random features like regenerative braking. Although it did work fine, purchasing a more suitable ESC is probably better.

TL;DR
Drive is important - do your research and figure out what works

== Weapon Systems ==
=== Horizontal Spinner Module ===
[[File:AnarchiHorizontalSpinnerWeaponModule1.png|center|thumb|600px|Picture of entire weapon module.]]

Anarchi's horizontal spinner weapon module frame consisted of 1/4" Aluminum 7075 Plates that were fastened together via 1/2" long 5-40 screws and weighed approximately 4lbs.The compartment for the weapon module was way too narrow resulting in the U-shape that was needed to give clearance to the belt as it spread outwards from the motor. In compartment ended up still being way too narrow as the belt would contact the edges as it spun up, causing some belt grinding and orange dust to form. The other "cat-shaped" hole behind it was a hole for the weapon ESC bullet connectors to come through to connect to the weapon motor bullet connectors.

[[File:AnarchiHorizontalSpinnerWeaponModule2.png|center|thumb|600px|Sideview of Weapon Module]]

The module was designed to interface with the chassis and screw in at multiple strengths due to the worry of the weapon module being ripped out. The plates were also held together by the 1/2" diameter shoulder bolt and locknut that held the weapon assembly in place.

The weapon motor was mounted and bolted down on straight slots that allowed the motor to be pulled back to adjust the belt tension.

[[File:AnarchiHorizontalSpinnerWeaponModule3.png|center|thumb|600px|Bottom View of Weapon Module]]

A midpoint for the slots was arbitrarily chosen and then a nominal cad representation of the belt from the motor from the midpoint of the slots and the weapon pulley was made. The outer circumference of the CAD-ed belt was then used to determine what outer circumference length belt to order from McMaster with the assumption that the belt could be pulled back enough to reach the right amount of tension. It suffered from alot of issues and points of improvement:

*The slots did not go far enough back as the polyurethane belt permanently stretched over the course of the matches, resulting in us having less than ideal belt tension and a weaker weapon in our third match even when our motor was pulled all the way back.
*Better means to calculate the belt length and longer tensioning slots should be pursued.
*Serpentine belts should also be considered over polyurethane belts as they seem to be stronger, of higher quality, and less prone to stretching.
*Another issue with straight slots was that a good hit could potentially loosen the weapon motor mounting bolts and cause the motor to be pulled forward and killing the belt tension so alternate tensioning slot geometries or methods should be considered.
*With the way our bot was hard to reach into or take apart, we had to pull the motor back by the screws which was difficult and likely caused us to not hit the right amount of tension we should have due to lack of grip strength. The bot should be designed so that the motor can be grabbed by the can and pulled back to tension the weapon belt.

=== Horizontal Spinner Weapon Bar ===

[[File:AnarchiHorizontalSpinnerWeapon1.png|center|thumb|600px|Horziontal SpinnerWeapon in CAD]]

====Design:====

Anarchi's horizontal spinner module utilized an asymmetrical style weapon with a longer impactor end and a wide counterweight to keep the center of mass along the axis of rotation, causing it to resemble a hammer. However, the impactor design was not made with a specific rake angle in mind but it was later measured to be 3.1 degrees. relief angle was also not considered in the design and was 0 degrees which may or may not be ideal. The weapon was made asymmetrical as it would increase the average bite (weapon insertion distance into opponent) by a factor of 2, improving the energy transfer to the opponent upon impact. the weapon It was 0.5" thick and made of AR500 steel which is considered one of the best materials for weapons that can be made via the waterjet. It weighed 4.509lbs and had an MOI (moment of inertia) of 74.825lb*in^2.The impactor ends were designed to sharp as they were intended to bite into opponents' armor better however its effectiveness didn't get the chance to be properly proven. It is constrained via 8 3/8-16 bolts that fasten it securely onto the pulley. The holes are "close fit" clearance holes (you can select a "close" option using hole wizard in Inventor) and in theory would allow a good bit of play if it weren't for the waterjet taper making the holes slightly smaller in reality. If you plan on trying to waterjet AR500 with closer fit clearance holes, it is essential that you do test cuts beforehand because AR500 is extremely difficult to machine. The hole in the middle is an inch long in diameter and was meant to allow a generous amount of clearance between the stationary spacers and the spinning steel weapon. Below is a useful pic of some basic dimensions.

[[File:AnarchiHorizontalSpinnerWeapon2.png|center|thumb|600px|Useful dimensions of weapon. Check CAD file for further details]]

====Analysis:====

WARNING: The following analysis was not conducted by an FEA expert so please be aware that the approach may be inaccurate and/or incorrect so be very skeptical.
[[File:AnarchiHorizontalSpinnerWeapon3.png|center|thumb|600px|Attempt at FEA Analysis on the weapon. Take this analysis with a bucket of salt]]

Rudimentary FEA was also conducted with an arbitrarily large load applied to a corner edge of the impactor and the weapon being constrained via 8 dowel pin parts where the contacts/constraints for the weapon were applied to simulate the bolts. It was found that the greatest stress occurred along the curvature between the central outer diameter and the length of the impactor similar to a cantilever beam with a constant end load. It was found that the greater the value of the curvature radius, the lower the max stress. An interesting thing to note is that the reaction forces on the contacts were calculated to be the greatest on the two rightmost bolts, 2nd greatest on the two bolts immediately to the left of them, and lowest on the bolts to the left of the center. This lead to the assumption that it was imperative to make the bolts be as large as reasonable to minimize the shear stress on the individual bolts to minimize the chances of the first two bolts on the right of the center failing. 3/8-16 bolts were selected due to the fact that they were the largest reasonable sized hole we could fit within the given geometry and that we already had taps for them in the shop.

A key element of designing an asymmetrical weapon is making sure the non impactor side won't be making contact with the opponent before the impactor does. The theory of bite is discussed in detail starting on page. 158 of the Riobotz Combot Tutorial. Our calculations, as linked below, assumed that the robot driving velocity would be 16.7mph and that the max rpm would be around 6528rpm. These values were produced by the Team Just'Cuz Robotics drivetrain calculator and the runAmok Spin-up calculator and as a result, both are not very accurate to real life (both better theoretical and validated models need to be developed). Based on the bite equation presented on page 158, our dmax was calculated to be 2.574803 inches with the average bite being 1.2874015 inches. Where our calculations differ from the Riobotz Combot Tutorial is that we check to make sure that the minimum distance at the point in the rotation where the weapon counterweight starts to pull away from the opponent is greater than zero to ensure that contact won't be made as this is the closest they will be to each other. We just made sure that this distance was greater than 0 since we knew the drive was going to be slower but it would be recommended to use some sort of safety factor for this in the future.
====Manufacturing:====

The weapon was waterjetted out of an approximately 0.5" thick AR500 steel shooting target from makeittargets.com. Make it ring targets don't have a super tight tolerance on their plate thicknesses as ours measured around 0.491" thick. The settings used on the waterjet cut are listed below and yielded very satisfactory results given the weapon didn't need to hit any tight tolerances unlike the press fit D-shape that Binari's weapon needed. In addition, most of the contours were cut on quality 3 while the clearance holes were cut at quality 5 since they would have to interface closely with the bolts. It's recommended to cut the "teeth" contours at a higher quality. The cut took approximately 58 minutes but we had no issues with it. The overall geometry came out nicely and the weapon was well balanced with no perceptible vibrations in the bot upon spinning up. The weapon was sandblasted to get rid of rust and mill scale which resulted in a clean, matte finnish.

Waterjet OMAX Make Cut Settings:

Material: Tool Steel D2 (RC 60)

Machinability: 54.08 (Metal)

Thickness: 0.55in

Tool Offset: 0.0125 inches

====Performance:====
*Weapon was very well balanced when spinning up.
*Due to drive not working well, anarchi's weapon was never able to achieve it's maximum possible bite, and therefore a really good hit, in its matches
*Waterjet taper made the holes slightly smaller than in CAD, resulting in little play, keeping the weapon pretty axially-symmetric with the pulley
*Sharp edges of impactor teeth started blunting slightly after the first two matches although this did not seem to off-balance the weapon any noticeable amount.
*Overall geometry of the weapon held up very well and no perceptible deformation was observed in the overall shape.
*Due to the ratio of bot wideness to weapon length, the area of protection/attack given by the weapon in the front of the bot was smaller than counterparts such as BEAM. Consider increasing weapon diameter or reducing bot width.
*The 8 3/8-16 bolts could possibly be overkill as some other horizontal spinners like BEAM have used configurations with slightly smaller and fewer bolts.
*Design wasn't made with a specific rake angle or relief angle in mind. The greater the rake angle, the better the weapon will be at biting into the opponent and transferring energy at the cost of blunting faster. If the rake angle is too large, it can make the teeth more fragile.
*A member from Hypershock recommends that the impactor side of weapons like that be flat on the end in order to prevent the insertion edge from prying itself out of an enemy bot's armor.
*Advantage of having weapon weapon being symmetric around the line between the impactor and counterweight is that you have two impactor teeth instead of just one meaning you can flip it around in case one of the teeth gets too blunted which would be a bigger problem given a larger rake angle. Issue is that you can't implement a large relief angle if you do that so it's a tradeoff. Relief angles also make the teeth weaker.
*Weapon was relatively light (under 20% of total weight) due to modular interface taking up weight. Will have hit harder if bigger. Many bots do between 20-33% of total weight.

=== Horizontal Spinner Weapon Assembly ===

== Electronics ==
{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| Vex 775 pro (brushed 12V motors)
 
|-
| Drive Motor Controllers
| Sabertooth Dual 25A 6V-24V Regenerative Motor Driver
|-
| Weapon Motor
| Horizontal: Scorpion SII-4035-250KV, Drum: HKIV-4025-1100KV
|-
| Weapon Motor Controllers
| HobbyWing Platinum PRO V4 120A ESC
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Zeee 22.2V 60C 4000mAh 6S Lipo Battery

|-
|}

== Competitions ==

=== [[AVC|AVC]] ===

*Results: 1-2
**Bracket Style: Double Elimination
***[Anarchi (loser) V.S. Wedgeham (loser): YouTube Link]
**** Match started with Wedgeham overwhelming Anarchi with it's superior driving by raming into us and pushing us into the wall repeatedly
**** Anarchi never tried to spin it's weapon up to maximum velocity due to the fear of self damage.
**** Anarchi landed a few small hits on wedgeham but none enough to do any significant damage due to the weapon not being able to reach it's max velocity
**** Half-way through the match, the gear boxes got internally damaged, slowing down our drive and our ability to move
**** When time hit 3 minutes, Wedgeham was the decided winner due to it being able to prevent us from spinning up or moving properly
**** After the match, it was determined that the left drive motor would no longer spin the drive wheel when above 60% throttle
**** We were unable to repair the gearboxes as the bot would have to be mostly disassembled in order to access them. The issue likely could've been solved if we had been able to easily open up the gearboxes
***[Anarchi (winner) V.S. Dragon Fruit (loser): YouTube Link]
**** Drive was much slower and harder to control. Had to slowly move anarchi towards the opponent
**** DragonFruit had a spinning active weapon and drive but seemed to also have some slight driving issues
**** Weapon was able to spin up to a high enough speed to rip off DragonFruit's wheel resulting in them tapping out.
**** After this match, orange powder from the polyurethane flat belts grinding against the inner side plate had formed and the bearings didn't spin as cleanly as previously (they felt slightly crunchier)
**** Weapon had suffered a small amount of blunting around the edges that made impact.
***[Anarchi (loser) V.S. Crippling Depression (winner): YouTube Link]
**** Drive had almost completely failed. Anarchi was unable to fully drive to the starting zone
**** Crippling depression fought in overcutter mode to likely avoid unnessecary damage to itself as Robert Cowan knew our drive was no longer working and he had matches left
**** Weapon was unable to spin up to a sufficient speed due to Crippling Depression's constant ramming. Crippling depression kept ramming us until our drive would not work at all.
**** More orange powder had formed and the weapon bearings now felt significantly more crunchy and spun less smoothly. In a perfect world, they should've been replaced before this match.

==== Issues ====

* Stuff
* Other Stuff

==== Changes to make ====

* Stuff
* Other Stuff

== Trivia ==
*The Vectrax was rendered inoperable twice by Chonki members (mainly Brian) during its construction.
[[Category: BattleBots]]
[[Category: FeatherWeights]]
[[Category: BigBots]]

Treasurer

2021-12-23T20:54:41Z

Ctyler31: Treasurer information started - still quite a few description to update

[[Category:Leadership Positions]]
The Treasurer is responsible for keeping track of all incoming and outgoing funds across all RoboJackets accounts. These records are maintained in the General Ledger. At the start of the fiscal year, the treasurer creates a financial plan for the entire fiscal year. The treasurer is also responsible for placing all orders. Accounts that the treasurer is responsible for include SGA, agency, CoC, Foundation, Endowment, and Mercury.

== Responsibilites ==

=== General Ledger ===
At the start of the fiscal year the Treasurer creates a system in Google Sheets to keep track of all incoming and outgoing funds across all accounts which includes the General Ledger, a collections sheet, a PO (purchase order) sheet for each team, and a PO sheet for general orders.

=== Financial Planning ===
At the start of the fiscal year, the treasurer creates a plan that includes estimates for all expected income and expenditures.

=== Placing Orders ===
There are three main ways the treasurer places orders

1. Reimbursement - Generally recommended for small orders (less than $ 100 or so) and time-sensitive orders. Required for PayPal payments due to fraud risk. Limited to $ 2000 as of FY20. Should be minimized if possible since reimbursement checks take weeks to arrive.

2. Purchasing card - Generally recommended for everything else (>$ 100 and <$ 2500).

3. Mailed check from Georgia Tech Accounts Payable - Use only when recommended by a SOFO accountant. This will require coordination with SOFO.

=== RoboJackets Accounts ===
SGA

Agency

CoC

Foundation

Endowment

Mercury

Vijay Car

2021-05-03T19:36:35Z

Ctyler31:

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Vijay Car
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== Vijay Car V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

==== Problems ====

* none

==== Good aspects ====

* everything

==== Changes/Improvements ====

* literally perfect

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Vijay Car

2021-05-03T19:35:28Z

Ctyler31:

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

==== Problems ====

* none

==== Good aspects ====

* everything

==== Changes/Improvements ====

* literally perfect

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Vijay Car

2021-05-03T19:34:26Z

Ctyler31: Created page with "{| class="wikitable" align="right" |- ! scope="row" colspan="2" style="background-color:#FFFF99" | botName |- ! scope="row" colspan="2" | File:..."

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Wonki

2021-05-03T19:34:02Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Varsiti

2021-05-03T19:33:54Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Roombi

2021-05-03T19:33:46Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Largetoni

2021-05-03T19:33:36Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Guillotini

2021-05-03T19:33:08Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

Dizzi

2021-05-03T19:32:40Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

2lb Competition 2021

2021-05-03T19:31:27Z

Ctyler31:

== Competition Summary ==

The RoboJackets 2lb Competition was hosted by RoboJackets on the 25th of April in 2021 in the SCC parking lot. All seven of the BattleBots new member teams competed in the single elimination tournament. In an effort to reduce machining time due to Covid-19, each team 3D printed the majority of their parts and the weight class was accordingly reduced from 3 pounds to 2 pounds. Due to issues with reaching this weight limit, the maximum allowable weight was changed from 2 pounds to 2.3 pounds the week before the competition. The competition was streamed live on YouTube.

Recording link: https://youtu.be/xidwKUf4gHc

== Results ==

The overall winner of the competition was Largetoni, a vertical spinner.

== List of competing bots==

* [[Dizzi]]

* [[Guillotini]]

* [[Humpti]]

* [[Largetoni]]

* [[Roombi]]

* [[Varsiti]]

* [[Wonki]]

* [[Vijay Car]]

Humpti

2021-05-03T19:29:14Z

{| class="wikitable" align="right"
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | botName
|-
! scope="row" colspan="2" | [[File:IMAGENAME.jpeg|frameless|right|300px|(Highlight text)]]
|-
! scope="row" style="text-align:left" | Year of Creation
| {{{year|2020-2021}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Versions
|-
! scope="row" style="text-align:left" | Current Version
| {{{currver|1.0}}}
|-
! scope="row" style="text-align:left" | Update Year
| {{{updyr|2020-2021}}}
|-
! scope="row" style="text-align:left" | Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" colspan="2" style="background-color:#FFFF99" | Information and Statistics
|-
! scope="row" style="text-align:left" | Weight Class
| {{{wc|2lb}}}
|-
! scope="row" style="text-align:left" | Weapon Class
| {{{weapc|weapon type}}}
|-
! scope="row" style="text-align:left" | Combined Wins/Losses
| {{{winloss|0/0}}}
|-
! scope="row" style="text-align:left" | Weapon Speed
| {{{TBA|(number) RPM}}}
|}

(insert summary here)

== Competitions ==

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

*Results:
**Single Elimination:
***[W/L vs ____]
**** (details of fight here)
***[W/L vs ____]
**** (details of fight here)

== Version ==

=== botName V1.0 ===

Created by: (Names of Builders/Group Members of aforementioned version of bot)

{| border="1" cellspacing="1" cellpadding="1" style="width: 500px;"
|-
| Drive Motors
| 22mm DC gearmotor 
|-
| Drive Motor Controllers
| Scorpion Mini Electronic Speed Control
|-
| Weapon Motor
| weapon motor name
|-
| Weapon Motor Controllers
| weapon esc name
|-
| Receiver
| Hobby King 2.4Ghz Receiver 6Ch V2 
|-
| Remote Control
| Hobby King 2.4Ghz 6Ch Tx and Rx V2 
|-
| Battery
| Turnigy Nano-Tech 1000mAh 3s 45~90c LiPo Pack
|-
| OTHER:
| 
|}

==== Problems ====

* (list problems)

==== Good aspects ====

* (list good aspects)

==== Changes/Improvements ====

* (list potential changes/improvements)

== Notes: ==

(random joke, optional)

(Naming inspiration, optional)

(Names of original builders)
[[Category:BattleBots]] [[Category:BeetleWeights]]

List of 3lb Robots

2021-05-03T18:54:13Z

Ctyler31: added 2020-2021 bots

= Drum Spinners =

==== 2020-2021 ====
*[[Humpti]]
*[[Varsiti]]

==== 2019-2020 ====
*[[Barbi]]

==== 2018-2019 ====
*[[Crispi]]
*[[Entropi]]
*[[Furi]]
*[[Groovi]]

==== 2017-2018 ====
*[[I]]

==== 2016-2017 ====
*[[Snuti]]
*[[Radii]]

==== 2015-2016 ====
*[[Emmii]]
*[[Misti]]

==== 2014-2015 ====
*[[Emmi]]

= Horizontal Bar Spinners =

==== 2020-2021 ====
*[[Guillotini]]

==== 2019-2020 ====
*[[Hibachi]]
*[[Perri]]

==== 2018-2019 ====
*[[Dadi]]

==== 2017-2018 ====
*[[Chewi]]
*[[Loki]]

==== 2015-2016 ====
* None :(

==== 2014-2015 ====
*[[Vicki]]

= Vertical Bar Spinners =

==== 2020-2021 ====
*[[Largetoni]]
*[[Roombi]]

==== 2019-2020 ====
*[[Huski]]
*[[Spooki]]

==== 2018-2019 ====
*[[Doori]]
*[[(un)Lucki]]

==== 2017-2018 ====
*[[Esci]]
*[[Grizzli]]

==== 2016-2017 ====
*[[Dat_Boi]]

= Ring/Shell Spinners =

==== 2020-2021 ====
*[[Dizzi]]
*[[Wonki]]

==== 2019-2020 ====
*[[Sauci]]
*[[Spinni-Boi]]

==== 2018-2019 ====
*[[WakiSmaki]]

==== 2017-2018 ====
*[[Personal Injuri]]

==== 2016-2017 ====
*[[Qti]]

==== 2015-2016 ====
*[[Sandi]]
*[[Shelli]]

==== 2014-2015 ====
*[[Smitti Werbenjagermanjensen]]

= Miscellaneous Bots =

==== 2017-2018 ====
*[https://hkim702.blogspot.com/2018/02/dynastinai.html Dynastinai]

==== 2014-2015 ====
*[[Group 5]]
*[[Flippi/MrWedge]]

= Graveyard of Bots with no Documentation =

==== 2016-2017 ====
*Schwifti
*Standi

==== 2015-2016 ====
*Ami
*Ghoti
*Flipboi

[[Category: BeetleWeights]]

2lb Competition 2021

2021-05-03T18:49:35Z

Ctyler31: Created page with "== Competition Summary == The RoboJackets 2lb Competition was hosted by RoboJackets on the 25th of April in 2021 in the SCC parking lot. All seven of the BattleBots new membe..."

== Competition Summary ==

The RoboJackets 2lb Competition was hosted by RoboJackets on the 25th of April in 2021 in the SCC parking lot. All seven of the BattleBots new member teams competed in the single elimination tournament. In an effort to reduce machining time due to Covid-19, each team 3D printed the majority of their parts and the weight class was accordingly reduced from 3 pounds to 2 pounds. Due to issues with reaching this weight limit, the maximum allowable weight was changed from 2 pounds to 2.3 pounds the week before the competition.

== Results ==

The overall winner of the competition was Largetoni, a vertical spinner.

== List of competing bots==

* [[Dizzi]]

* [[Guillotini]]

* [[Humpti]]

* [[Largetoni]]

* [[Roombi]]

* [[Varsiti]]

* [[Wonki]]

* [[Vijay Car]]

BattleBots

2021-05-03T18:33:35Z

Ctyler31:

Welcome to the '''[http://www.robojackets.org/ RoboJackets]''' BattleBots wiki! [[File:bb pic.jpg|thumb|right|400px|BattleBots team at Motorama 2018]]

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: Cody Page
* 3lb Manager: Cade Tyler
* Chonki Bot Lead: Brian Epstein
* Hocki Bot Lead: Varun Madabushi
* Maori Bot Lead: Dennis Crawford
* Valkryi Bot Lead: Sam Li
* Samurai Bot Lead: Dylan Adriano

== 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 BattleBot/Sumo 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 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 either a Sumo team or a bigger 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]]

== Documentation ==

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

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

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

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

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

===== 2016 Competition =====

*[[Motorama_2016|Motorama 2016]]
*[[RoboGames_2016|RoboGames 2016]]

===== 2015 Competition =====

*[[Motorama_2015|Motorama 2015]]
*[[RoboGames_2015|RoboGames 2015]]

===== 2014 Competition =====

*[[BattleBots_2014_Tasks|Tasks]]
*[[BattleBots_2014_Meeting_Notes|Meeting Notes]]

===== 2013 Competition =====

*[[BattleBots_2013_Tasks|Tasks]]
*[[BattleBots_2013_Meeting_Notes|Meeting Notes]]

===== 2012 Competition =====

*[[BattleBotsPhotos2012|Photos]]
*[[BattleBots_2012_Tasks|Tasks]]
*[[BattleBots_2012_Meeting_Notes|Meeting Notes]]

===== 2011 Competition =====

*[http://www.robojackets.org/gallery/main.php?g2_itemId=7317 2011 Competition Pictures]

== Resources ==

*[http://www.robojackets.org/teams/battlebots/ RJ BattleBots Overview Page]
*[https://lists.gatech.edu/sympa/info/robojackets-battlebots RJ BattleBots Mailing List]
*[http://robogames.net/ RoboGames]
*[http://www.riobotz.com.br/tutorial.html Riobotz Tutorial] (400 page book on how to build a BattleBot. Great resource.)
*[http://www.battlebots.com/ Battlebots.com]
*[http://www.botrank.com/ BattleBots Ranking]
*[http://www.buildersdb.com/ Buidersdb.com]
*[http://www.robotmarketplace.com Robot Marketplace] (good source for motors, drivers, etc.)
*[[BattleBots BeetleWeight Wiki Template]]
*[[Competition Tool Packing List]]
*[[Robot Basics]]
[[Category:BattleBots]]

3lb Beginner's Guide

2020-05-09T09:37:04Z

Ctyler31: Switched disadvantage columns for Aluminum 6061 and 7075. Also switched "HDPE aluminum" to "HDPE" for cost of HDPE plate.

== Introduction ==
Welcome to the RoboJackets BattleBots 3lb Beginner's Guide!

The purpose of this guide is to educate the reader on some key factors relating to the 3lb weight class of BattleBots, such as common robot types, the design process, and common materials/components. While originally intended for members of the RoboJackets team, this guide contains information that is relevant to anyone trying to get into BattleBots!

This guide primarily focuses on robot design, rather than information on the actual competition. For information about competition rules, it is often different between competitions so please visit that competitions website or social media for specific rules. However, for a good generic set of rules that are common across most competitions you can look at the Northeast Robotics Club (NERC) rule set [http://www.nerc.us/rules.html here].

== Choosing a Robot Type ==

=== Introduction ===

Within the 3lb weight class of combat robots there are five common robot types found. This section will quickly introduce these commonly found robot types, and explain their similarities, differences, pros, and cons. By the end of this section, you'll have a clearer idea of what kind of robot is most interesting to you, as well as the associated design challenges of that robot type.

=== Drum Spinner ===

[[File:(Radiis).jpeg|right|thumb|320x180px|'''Drum Spinner - Radi and Radii''' Designed and built by RoboJackets Members (2016-2017)]]

This weapon is a spinning solid cylindrical drum with teeth at the front of the robot. It is driven similarly to a vertical or horizontal spinner with a pulley system between the weapon and weapon motor.

'''Pros'''
* Great beginner bot
* Reliable due to simple weapon
* Outputs good damage
* Weapon doesn't require too much space away from the rest of the bot
* Easy to design so it can drive while flipped

'''Cons'''
* Smaller strike zone
* Gyroscopic effect can make fast turns hard
* Large heavy weapon

'''Example Drum Spinners designed and built by RoboJackets'''
* [[Radii]] - 3rd place winner at Motorama 2017
* [[Snuti]] - Competed at Motorama 2017 and Sparkfun 2017

=== Horizontal Spinner ===

[[File:chewi.jpg|thumb|320x240px|'''Horizontal Bar Spinner - Chewi''' Designed and built by RoboJackets Members (2017-2018)]]

The weapon is a flat spinning bar or disk at the front of the robot. It is also driven similarly to a drum or vertical spinner with a pulley system between the weapon and weapon motor.

'''Pros'''
* High damage output
* Large strike zone
* Easy to design so it can drive while flipped
* Weapon can withstand significant damage without breaking (bent weapon still functions well)

'''Cons'''
* Robot must extend out to avoid its own weapon
* Gyroscopic effect make turning fairly difficult
* Needs a lot of structural support on the weapon to prevent damage from recoil

'''Example Horizontal Spinners designed and built by RoboJackets'''
* [[Ki]] - Competed at Sparkfun 2016 and Motorama 2017
* [[Chewi]] - Competed at Motorama 2018, RoboGames 2018, and Sparkfun 2018
* [[Daddi]] - Competed at Motorama 2019

=== Vertical Spinner ===

[[File:Golden Esci.jpeg|thumb|'''Vertical Bar Spinner - Esci''' Designed and built by RoboJackets Members (2017-2018)]]

A robot with a vertically spinning weapon at the front of the robot. Typically this weapon is complemented by a surrounding wedge to lift opponents into the weapon. It is also driven similarly to a drum or horizontal spinner with a pulley system between the weapon and weapon motor.

'''Pros'''
* Great damage output
* Allows for the use of a wedge, which acts as armor and directs bots into the weapon
* If the weapon breaks, it still functions as a wedge bot

'''Cons'''
* Hard to allow for driving when flipped
* Gyroscopic effect can make driving difficult
* Weapon has to be smaller to maintain a low center of gravity (keep the bot short)

'''Example Vertical Spinner designed and built by RoboJackets'''
* [[Esci]] - Competed in Motorama 2018 and RoboGames 2018

=== Ring Spinner ===

[[File:Smitti.png|thumb|240x240px|'''Ring Spinner - Smitti''' Designed and built by RoboJackets Members (2014-2015)]]

This weapon is a spinning ring with teeth that surround the entire frame. Generally, the ring is supported by "rollers", which have bearings to reduce friction and support the ring with a male-female interface. The ring is typically driven directly by the weapon motor, which has a casing of a high friction material such as rubber.

Additionally, there is a variant of the Ring Spinner called the Shell Spinner. The Shell Spinner is nearly identical to the Ring Spinner, except instead of a "ring" that is spun around, the entire robot is covered in a shell, which is spun. This allows for even more weapon coverage, at the cost of more weight being required for the larger shell, as well as the need for a stronger motor to spin it.

'''Pros'''
* Perfect 360 strike zone
* Hard to compete against
* Easy to design so that you can drive while flipped

'''Cons'''
* Difficult to design and assemble
* Weapon takes all the blows and can break
* Can be difficult to drive

'''Example Ring Spinners designed and built by RoboJackets'''
* [[Qti]] - Competed in Motorama 2017
* [[Smitti Werbenjagermanjensen]] - Competed in Motorama 2015

=== Wedge ===

[[File:AverageWedgeBot.jpg|thumb|240x240px|Average Wedge (Artist Rendition)]]

The weapon is the bot itself with the main structure forming a wedge with the intent on trying to flip over, or lift the enemy bot off the ground.

Members of the RoboJackets Battlebot team do not build Wedge's because there is no real design challenge in designing a Wedge, and RoboJackets values the educational experience of designing a more complex robot. Building a more complex robot allows you to learn engineering skills that scale to more advanced competitions. Ultimately, while Wedge bots may be good at winning competitions winning the competition isn't the goal. The true goal is to learn about the design process and have fun!

'''Pros'''
* Very simple to build
* Can be built incredibly strong due to a heavier structure, thanks to the lack of a traditional weapon taking up valuable weight.
* Doesn't have a weapon that would produce a gyroscopic effect that would inhibit driving. Being able to drive easier allows the driver to be more aggressive, which judges often favor when determining a winner.

'''Cons'''
* Doesn't challenge your engineering abilities as much as a bot with a traditional weapon.
* No true destructive power which means if the enemy cannot be flipped or lifted, winning will be very difficult.

== Design Process ==

=== Introduction ===

Now that you have selected a robot type, you're ready to start designing and building! The following is a detailed explanation of the design process for the RoboJackets BattleBots team. While this is specific to our team, it can be used as a general guide for any team that wants to improve their design process.

Being successful in competitions starts with the design process. While everyone wants to immediately jump into machining and get their bot done, without a proper design process the end result will be ineffective and probably nonfunctional. Additionally, without a proper CAD assembly with accompanying dimensions machining will not result in usable parts. So while it might not be as exciting as machining and assembling, it pay off in the end. Spending extra time on the design process will highly increase the quality of your final design and assembly.

[[File:Diagram2.jpeg|800x487px]]

=== Step 0: Brainstorming ===

[[File:Senpai_Brainstorm.jpg|thumb|upright=0.65|Example Brainstorm Sketches]]

The design process begins unofficially with brainstorming. Once you have an idea about what type of bot you want to build
* Research notable examples of that type of bot.
* Look for examples with different types of weapons, armor, and drive systems.
* Try to find some videos of these bots actually competing.
* See what works and what doesn't about different designs.

Once you've seen enough through researching different robots...
* Start piecing together your ideas into complete concepts once you've seen enough.
* Do a rough sketch of the shape of the chassis, weapon, etc.
* If there are some unique features on your concept, write out some notes so that when you or your team revisit it, it will be more easy to understand.

Don't limit yourself to just one idea either, the more ideas you bring to your team during the first few meetings when you decide on an overall design, the better. It is worth mentioning that you will be on a team, so don't get TOO attached to one idea, as not one person on the team will end up having designed the entire bot.

On the right, you can see an example of what good brainstorm sketches look like. There are many ideas drawn out, with a variety of features demonstrated between them. Things to focus your brainstorming on would include...
* Weapon type
* Weapon shape
* Drive system
* Overall shape
* Armor

It's important to note that no idea is a bad idea during the brainstorming phase. Any and all ideas are beneficial. While a given idea may not work, when you gather with your team you may find that a teammate will have an idea that could take a not so good design and make it great. Additionally, you may find that your team will go back to these brainstorming ideas for inspiration to solve issues with the design way down the line. In other words, the more ideas you come up with and put down on paper, the better!

=== Step 1: Sketch ===

[[File:Senpai_Top_Down.jpg|thumb|upright=0.5|Example Intermediate Sketch]]
[[File:Senpai_Final_Sketch.png|thumb|upright=0.5|Example Final Sketch]]

This is when the design process will start properly. Once you're on a team, the first goal is to come up with a bot design. Think broad. Focus on features. The design process is iterative, so you will make changes to this design. However, this doesn't mean that it's not worthwhile to come up with some rudimentary overall dimensions, such as the overall length, width, and height of the bot. These dimensions can be based loosely off of previous bots as a guideline.

On the right, there are two examples of sketches that would be created during this stage in the design process.

The top sketch is a good example of what should be drawn at the start of the sketching step. As a team, you will produce several of these sketches, each time adding more details as you discuss the design. As you can see this top view shows the approximate location of the frame, wheels, motors, and weapon. Details such as fasteners and electronics are not yet included, as this sketch would be developed before those are considered. It is important to work out details in a logical order.
# Start with a sketch similar to those in the brainstorming phase and work out how the structure would work.
# Add in larger important things like the weapon and armor.
# Add in smaller important things like the motors, wheels, and belts.
# Add in the fine details like wires, electronics, and fasteners.

This process will allow you to logically work through taking a concept in your mind and putting it onto paper.

As more details are finalized, the sketches will become increasingly complex. Eventually, your team should have a detailed final sketch, such as the bottom example. As you can see, most if not all components are included. Multiple views are included as well, which will significantly help with visualization of the final design. It's noteworthy to see that while the sketch is incredibly detailed (and no you don't need to be an artist, most final sketches won't look this good), it still wouldn't be enough to jump directly into CAD. That's why we have the next step!

=== Step 2: Draw ===

[[File:Senpai_Joint_Sketch.jpg|thumb|upright=0.5|Example Joint Drawing]]
[[File:Senpai_Individual_Part.jpg|thumb|upright=0.5|Example Part Drawing]]

Once you've got an overall sketch of the bot, its time to start drawing some individual parts out and assign them some dimensions. This is important, as having some predetermined dimensions will make the CAD process easier. Make sure that your team is communicating during this process, as its important that everyone understands the dimensions so that any given member could make the CAD part for any given part. The more your team understands the dimensions you define, the faster and more efficient the CAD process will be. Additionally, drawings should be made that give explicit details in areas of the bot that have complex assemblies and sections of the bot. Having these draw out ahead of time will expedite the process of translating the drawing into a CAD assembly.

You will also have to determine what material the parts are made out of. See the Commonly used materials section for more details

Another thing to consider during this time is how you will attach the parts into a complete assembly. Consider using a puzzle-fit, the number of screws used to connect two parts, location of holes, and size and type of screws. Beware intersections of screws, and don't have so many screws that your part is completely filled with holes, or "Swiss-cheesed".

The top right image shows a detailed drawing which provides details about the materials and assembly of a given joint. Without this drawing, just using the final sketch, it would have been much harder to translate this isn't CAD.

The middle right image shows a detailed drawing for the assembly of the motor and the motor mount. Once again, the added details would make it much easier for the creation of the part in CAD.

This step can be done simultaneously with Steps 3 and 4, as you draw and dimension parts as you need them during the early meetings. However, it's important not to put off finishing the drawings for all parts, as it can make it harder to work outside of meetings. There should always be a group present when dimensioning parts, so if you don't have any parts that are dimensioned, you can't make a good CAD part.

=== Step 3: Picking a motor ===

When picking a motor, there are 3 things to consider. The motor properties (things specific to the motor you '''cannot''' control), the design properties (things specific to your design you '''can''' control), and the desired specifications (specifciations that you want in the end).
Motor properties you cannot control:
* '''KV (RPM/V)''': This will be used alongside our voltage value to find the Rotations Per Minute (RPM) of the motor.
* '''Power (W)''': This will be used alongside our calculated RPM value to find the Force and Spin-up time for the weapon. This value is typically between 500-800W.
* '''Max Current (A)''': This is an important number to know, as it will affect which ESC you need. The greater the max current, the bigger and heavier ESC you will need, so aim for a low max current.
* '''Max Voltage (V)''': This will be used alongside our KV value to find the RPM of the motor
* '''Dimensions''': The size of the motor is also an important factor to keep in mind, as a large motor could force you to build a larger bot to house it. A larger bot will end up needing thinner, smaller, and weaker walls to keep the weight below 3 lbs.
* '''Weight''': Obviously the weight of the motor matters, as a heavy motor will make it harder to build a sturdy bot due to the use of less heavy but weaker walls.

Please note that some websites have a bad habit of listing the dimensions and weight of the box the motor comes in, rather than the motor itself.

Also, be aware that many of the values provided by websites are the theoretical maximums, and won't be what you actually observe. However, for the sake of these calculations, you can just use these values.

Design properties you can control:
* '''Gear ratio''': The gear ratio is the ratio of the diameter of the motor to the diameter of whatever you are rotating, like a pulley or the weapon drum. This will be an important factor, as it will determine the RPM of the weapon.
* '''Mass Moment of Inertia (J)''': This will be used in your calculations for Force and Spin-up time, and it can be found by making the weapon in Inventor, then checking its physical properties.

End Specifications that you desire:
* '''Weapon RPM''': This will be an important factor for your over destructive capability. For smaller spinning weapons, such as a drum, RPMs greater than 8000RPM are desirable. For larger spinning weapons, such as a bar, RPMs between the range of 2000-5000RPM are desirable. This number is lower than the smaller weapons because if you RPM is too high with a bar spinner, you risk significant recoil when you hit the enemy and severe gyroscopic effects inhibiting responsive driving. Its one thing to rip the opponent's bot in half, but if you destroy your own bot in the process it's meaningless.
* '''Spin-up time (s)''': This value represents the amount of time required to get the weapon from rest to its max RPM. The first to strike in the competition will often gain the immediate upper hand and if the enemy bot runs into your weapon before its spun-up completely, you will deal little to no damage and the weapon will once again need to spin-up from rest again. Keeping this value as low as possible is incredibly important. In general, a Spin-up time of around 1 second would be reasonable, but ultimately it's up to your team to make the call on what you think is an acceptable amount of time.
* '''Kinetic Energy (J)''': This value represents the actual energy that your spinning weapon will produce, and therefore transfer into the other robot.

As part of getting these values, you will have to calculate several more values. The process by which you calculate these values and the ones mentioned in this section can be found below in the Calculations section of this guide.

Also, it is worth mentioning that these values that we calculate are fairly simplified, and there are many more factors that will affect the true values of these factors, however for the sake of choosing a motor, an approximate value will suffice.

=== Step 4: CAD Parts ===

This step will actually start at the same time as you're looking at choosing a motor. As part of your calculations, you will need the weapon to made in Inventor so that you can get its Mass Moment of Inertia. From there you will need to create a part for the motor that your team ends up choosing, using the dimensions and weight provided by the website you found the motor on.

Remember that the parts will need to be manufactured from stock, so once you have determined a way to manufacture a part, check how much the stock you'd need will cost and how much material will be wasted as part of your manufacturing. For example, if you have a part that you know how you could manufacture, but it would require a $100 chunk of aluminum, most of which is removed in the process, maybe look at redesigning the part to be simpler so it can be manufactured with cheaper stock.
Here are some tips for making combat robot parts in CAD...

* ''' Assign dimensions ''' in a way that makes it easy to go back and change the values later. This is often accomplished by avoiding making dimensions all dependent on each other, and instead of keeping them based off of the part's overall dimensions.
* ''' Utilize any standardized CAD''' parts for things like electronics that may be provided either online or by a mentor. This will save you the time that would be spent making the part yourself.
* '''Assign the material property of a part''', to ensure that it's reported weight is correct. The default "generic" material will not accurately report your weight, which will result in you being overweight once everything is built. You also may find that you have only made half of the parts you need, and the overall weight is already too high. With this information, you can go ahead and adjust the dimensions of the parts you've already made to reduce the weight.
* '''Begin working on your assembly''' earlier rather than later! You don't need to actually have every single part in CAD before you start putting parts into an assembly. See the next step for more information!

Proper CADing is a team effort, not a solo endeavor. When you work alone, you risk misinterpreting a dimension or drawing. During meetings, one or two people should be actively working on the CAD with the remaining members talking through the process with them. Communication is key! You will end up creating quality uniform parts only by working together. Taking turns working on parts is also important, to ensure everyone gets time working with Inventor. Please remember that it is expected that your team will meet and work outside of our regularly scheduled meetings!

=== Step 5: CAD Assembly ===

Once the parts are made, its time to start putting together an assembly. You'll need to completely finish the assembly before you can undergo a design review. There are several "Do's and Dont's" to consider with the assembly...
* '''Do''' focus on making sure the overall weight is below 3lbs. It's important to have an assembly that is not only below 3 lbs but is safely below 3 lbs.
* '''Do''' account for the weight of things potentially not present in the assembly, such as wires, connectors, and material imperfections.
* '''Do''' add in the fine details like screws and clearances between parts to account for inaccuracies when cutting out parts.
* '''Do''' create sub-assemblies, which will allow your team to work on multiple aspects of the robot simultaneously.
* '''Don't''' assume that something can be left out of the final assembly. The assembly should include every feasible component as the real thing.
* '''Don't''' assign random colors and textures to parts. This will make it harder for people to understand the intended materials from appearance alone.
* '''Don't''' underestimate the amount of work required to put everything into an assembly. Oftentimes new issues will present themselves after putting everything together.
* '''Don't''' make all changes in the same assembly. Save copies of your assembly along the way, so you can reference the old versions if need be.

During this time, it is also important to begin working on a Bill of Materials, or BOM for short. This BOM will be a master list of the materials required to create the robot, and where they can be purchased. While there is no specific format for a BOM, the following are expected to be included in one...
* Dimension of stock plates/sheets required to manufacture parts.
* Quantity of non-stock materials such as screws, bearings, and belts.
* Sources for where the materials can be purchased.
* Any necessary notes related to the parts and materials needed.
Keeping an accurate and through BOM will allow you to launch directly into manufacturing as fast as possible after the design is complete.

=== Step 6: Design Review ===

The whole design process is leading up to one thing: The Design Review. During the design review, you will present your team's assembly to the rest of the BattleBots team. Both your peers and the senior members will ask you questions about your design and point out design flaws and recommendations on how to address them. Often times your first design review will be fairly harsh, with senior members finding plenty of issues with your design. While this may seem mean-spirited, they are simply trying to help you build the best bot that you can. The larger bots will often undergo the design review 3-5 times before they are finally approved to start machining, so even the senior members have to go through this process. Because the 3 lb bots are much simpler, usually only 2 design reviews will be needed.

'''It's important to take notes during the design review, as even a "good" design review will result in enough changes that you'll need to write them all down. You will likely get a lot of feedback, and while in the moment you may feel like you'll remember it all it will be impossible to remember every little comment.'''

=== Step 7: Revise and repeat ===

Once you get out of a design review, it's important to strike fast while the iron is hot. After your first design review, there will more than likely be several huge changes that you'll need to make to both your individual parts and the assembly as a whole. There is NOT a lot of time between the first and second design reviews (often only a week or two), due to the natural time constraints of the 3lb program. So it's important to start working on these changes sooner rather than later. It's important to also make sure you address ALL the things that are mentioned during the review, as it's important not the waste everyone's time with repeat issues from the previous review.

=== Step 8: BUILD! ===

Now finally you can begin manufacturing! Keep in mind...
* You will need to make minor adjustments to the design as you manufacture, and when you do so make sure to update your CAD to reflect these changes.
* Beware changing too much and causing the overall assembly to be overweight.

== Calculations ==

Below is a step by step guide on the calculations required to determine what motor to choose for your bot. Keep in mind these calculations are fairly simplistic and don't take several real-world factors into account. Additionally, these values will be computed based off of what is reported by the manufacturers, which are often "best case scenario" and are not what you should expect to see in practice.

=== Step 1: Get values for the motor ===

The first step is to retrieve the following values off of the distributor/manufacturer's website.
* '''KV''': Motor Velocity Constant (RPM/V)
* '''P''': Power (W)
* '''V''': Voltage (V)

=== Step 2: Determine values regarding the weapon ===

The next step is to determine a few values from your design of the weapon.
* '''J''': Mass Moment of Inertia (lbf*ft*s^2)
* '''e''': Gear Ratio (Drive gear/Driven gear)

=== Step 3: Determine intermediary values ===

In order to calculate our desired values, we need to calculate some intermediary values to use in our later calculations.
* '''ω''': Angular Velocity (rad/s)
* '''RPM''': Rotations Per Minute
* '''τ''': Torque (lbf*ft)

'''RPM = KV * V'''
'''ω = RPM * (2π / 60)'''
'''τ = P / ω'''

=== Step 4: Adjust values according to gear ratio ===

Some of our values need to be adjusted according to what gear ration is being used between the motor and the weapon.
'''ωoutput = ωinput * e'''
'''τoutput = τinput / e'''

For the calculations past this point, please use these new "output" versions of ω and τ in place of our old values.

=== Step 5: Get our desired values ===

Finally, we are ready to calculate the final values that we actually want!
* '''KE''': Kinetic Energy
* '''t''': Spin-up Time (s)

'''KE = 0.5 * (ωoutput ^ 2) * J'''
'''t = 3 * ((0.63 * ωoutput * J) / τoutput)'''

= Standard Robot Components =

Provided below is a table containing information on some of the standard components found on nearly every 3lb combat robot.

{| class="wikitable"
|-
! scope="col"| Component
! scope="col"| Description
! scope="col"| Size and Weight
! scope="col"| Image
|-
! scope="row"| Drive Motor
| The motor used to drive the robot around. Typically these motors don't need to be incredibly strong. An example motor used by RoboJackets BattleBots is the '''DYS BE1806 2300KV Motor'''. You will need two
| The DYS BE1806 2300KV Motor weighs '''0.053 lbs''' and is approximately '''0.91x0.91x0.83in'''.
| [[File:Drive_Motor.png|175px]]
|-
! scope="row"| Drive Motor ESC
| Electronic Speed Control used for the Drive Motor. An ESC is required to power and control the motors. An example ESC used by RoboJackets BattleBots is the '''DYS BL20A Mini 20A BLHeli ESC OPTO'''. You will need two.
| The DYS BL20A Mini 20A BLHeli ESC OPTO weighs '''0.017 lbs''' and is approximately '''0.91x0.47x0.18in'''.
| [[File:Drive_ESC.png|175px]]
|-
! scope="row"| Receiver
| The receiver that gets the signal from the controller to control the bot. An example receiver used by RoboJackets BattleBots is the '''HobbyKing 2.4Ghz Receiver 6Ch V2'''.
| The HobbyKing 2.4Ghz Receiver 6Ch V2 weighs '''0.029 lbs''' and is approximately '''1.75x0.53x0.88in'''.
| [[File:Receiver.png|175px]]
|-
! scope="row"| Battery
| Power Supply for the robot. A 3 cell 11.1V battery is common for this weight class. An example battery used by RoboJackets BattleBots is the '''Turnigy nano-tech 1000mah 3S 45~90C Lipo Pack'''.
| The Turnigy nano-tech 1000mah 3S 45~90C Lipo Pack weighs '''0.21 lbs''' and is approximately '''2.80x1.38x0.75in'''.
| [[File:Battery2.png|175px]]
|-
! scope="row" colspan="4"| Total Approximate Weight of Standard Components: 0.519 lbs
|}

= Commonly Used Materials =

In this section, I will describe some of the most common materials used to build a 3lb combat robot. Aluminum, Steel, and Plastic are the most commonly used materials for building a 3lb robot. While there are a few more materials that some teams use (e.g. carbon fiber or titanium), these three materials are affordable, lightweight enough to be used in a 3lb combat robot, common enough that they can be easily purchased from a variety of sources, and strong enough to be used in for combat.

== Aluminum ==

'''Common Uses'''
* Majority of structural pieces
* Any non-striking surface that needs to be strong
* Drum for drum spinners

'''Features'''
* Moderately light
* Moderately strong
* Good all-purpose material

Aluminum is one of the most commonly used materials for building a combat robot. This is because it is lightweight but strong enough to be used for the core structure of the robot.

The most commonly used aluminum alloys are 6061 and 7075. Below are some of the advantages and disadvantages between these two alloys,
{| class="wikitable"
|-
! scope="col"|
! scope="col"| 6061 Aluminum
! scope="col"| 7075 Aluminum
|-
! scope="row"| Advantages
|
* Significantly cheaper
* Easier to machine
|
* Significantly stronger
* Resists deformation
|-
! scope="row"| Disadvantages
|
* Much weaker
* Doesn't resist deformation
|
* Significantly more expensive
* Much harder to machine
|}

RoboJackets typically sources its aluminum from [https://www.midweststeelsupply.com/store/ Midwest Steel Supply] and [https://www.mcmaster.com/ McMaster-Carr]. A 12" x 12" x 0.25" plate of 6061 aluminum costs approximately $22.

== Steel ==

'''Common Uses'''
* Screws and fasteners
* Weapon teeth for drum spinners and ring spinners
* Overall weapon for vertical and horizontal spinners
* Any striking surfaces

'''Features'''
* Very strong
* Very heavy
* Great for resisting deformation

Because of its heavyweight, steel should be used sparingly, and it is typically reserved for the part that strikes the enemy robot. This is to ensure that all of the energy of the collision is transferred into the enemy bot, and not into deforming your weapon. Additionally, steel is often utilized as the striking surface on the weapon.

The most common type of steel used is low-carbon steel as it is easy to machine, strong, and fairly cheap.

RoboJackets typically sources its steel from [https://www.midweststeelsupply.com/store/ Midwest Steel Supply] and [https://www.mcmaster.com/ McMaster-Carr]. A 12" x 12" x 0.25" plate of steel costs approximately $40.

== Plastic ==

'''Common Uses'''
* Disposable armor pieces
* Any part that won't experience stress
* Internal walls to prevent contact between various components

'''Features'''
* Very light
* Reasonably strong
* Deforms easily

Plastic is a fantastic material for armor, as it is lightweight, cheap, and surprisingly strong! Armor on a 3lb combat robot is not supposed to be rigid, and strong, as that means whatever energy that is transferred into the armor gets then transferred into the robot's structure. Plastic dissipates the energy that is passed into it by breaking and being ripped apart. Due to the low cost and high machine-ability, you can manufacture several sets of armor pieces and replace them as they are broken. This is much better than having to manufacture and replace core structural components!

The most commonly used type of plastic used is High-density polyethylene (HDPE) because it provides a high strength-to-weight ratio and is fairly elastic. When used as armor, HDPE plastic will "bounce" most glancing blows off of your robot.

RoboJackets typically sources its HDPE plastic from [https://www.mcmaster.com/ McMaster-Carr] and [https://www.eplastics.com/ ePlastics]. A 12" x 12" x 0.25" plate of HDPE costs approximately $8.

= Helpful Links =

*[[List of 3lb Robots]] - List previously built robots, sorted by robot type
*[[Electronics Basics]] - Guide to the basics of the electronics typically used
*[[3lb Documentation Guide]]
*[[3lb Design Log Guide]]

[[Category:BattleBots]]