Velociti

Velociti
Year of Creation	Fall 2021 - Spring 2022
Wins/Losses	0/4
Velocitii
Year of Creation	Spring 2022
Wins/Losses	0/1
Velocitii.5
Year of Creation	Spring 2023
Wins/Losses	0/2
Information and Statistics
Weight Class	BeetleWeight
Weapon Class	Horizontal Spinner
Combined Wins/Losses	0/7

Velociti is a beetle weight horizontal spinner designed and manufactured in 2021-2022. Velociti's weapon is roughly S-shaped and the frame mostly follows the standard RoboJackets chassis design with the addition of extensions on the top and bottom plate for better forming of HDPE side armor.

Its successor, Velocitii, is a complete redesign of the robot following an unsuccessful performance at Motorama. The new design features a disk weapon that sits lower to the ground and several new space saving considerations detailed below.

Competitions

Motorama 2022

• Results: 0-3
  • Bracket Style: Double Elimination
    • [(https://youtu.be/vdd1TYPd-1U) Loss vs Melon Bot]
      • After clutching up the safety inspection, Velociti's first opponent was a D2 kit bot wedge
      • After a few hits, the weapon refused to spin up, and wedge vs wedge combat began
      • It is uncertain as to if the weapon motor issue was due to an electrical problem or driver error
    • [(https://youtu.be/U4rhVIlsDw0) Loss vs Starchild]
      • Velociti's next opponent was a large wheeled bot with a controllable arm and a small sawblade at the end
      • Starchild's weapon immediately gave up, likely as a result of intimidation, and Velociti landed a few hits before the belt slipped upwards
      • Once again, despite taking no discernable damage whatsoever, Velociti lost due to judge decision
  • Grudge Matches
    • [(Video Link) Loss vs Mechanical Advantage]
      • To satiate Velociti's hunger for combat, a random grudge match proposal was accepted against a drum spinner
      • Once the match began Velociti decided to psyche out the opponent with an advanced tactical maneuver and did an immediate 180
      • A brief moment of contact with the opponent's drum resulted in the instant removal of the back plate, left wheel armor, right wheel armor, and LiPo Battery
  • Robojacket Rumble
    • [(Video Link) Blood sacrifice to Chonkii]
      • As a grand finale, all of the 3lb robots were placed in a cage match against Chonkii and Crab King
      • 1 hit from Crab King and 2 more from Chonkii rendered Velociti completely disemboweled

RoboJackets In-House 2022

• Results: 0-1
  • Bracket Style: Single Elimination
    • [(Add Link) Loss vs PapaJonni]
      • Several ESC problems occurred beforehand
      • A few good hits went down but ultimately the belt was too loose and the weapon wouldn't spin up more
      • Drive system was still as bad as Velociti

RoboJackets Grudge Matches 2023

• Results: 0-2
  • Bracket Style: Double Elimination
    • [(Add Link) Loss vs Scampi]
    • [(Add Link) Loss vs Nasti]

Version History

Velociti (Version 1.0)

Created by: Jacques Wang, Austin Graves, Evan Strakes, Divyam Kumar, Bryce Parsons, Hanran Wu, and Brian Yang

Drive Motors	BotKits 22mm (The one they gave us)
Drive Motor Controllers	Scorpion Mini ESC (The one they gave us)
Weapon Motor	Propdrive v2 2836 1400KV Brushless Outrunner Motor
Weapon Motor Controllers	Hobbyking 60A (2~4s) ESC 4A SBEC
Receiver	HobbyKing HK-TR6A (The one they gave us)
Remote Control	The one they gave us
Battery	Turnigy nano-tech 1000mah 3S 45-90C Lipo (The one they gave us)

Design Summary

• Weapon
  • 3/8" steel weapon shaped like an integral with the intent to shrink the surface area of the weapon's point of impact
  • Holes later added to reduce its weight from ~14.5 oz to ~12.5 oz
  • Weapon Pulley mounted directly above weapon and bolted to the weapon, with two bearings allowing the weapon assembly to spin around the fixed shoulder bolt axle
  • HDPE tower of washers and HDPE guards later added to ensure the weapon and motor pulleys remained aligned and to prevent the belt from slipping

• Chassis
  • Relatively standard puzzle fit chassis for a horizontal spinner
    • Consists of an aluminum top plate, bottom plate, 2 side plates, and a non-loadbearing HDPE backplate
  • Main feature being the addition of extensions on the top and bottom plates to attach and guide wheel armor

• Drive
  • As with most horizontal spinners, the drive mechanism involves only 2 drive motors and the robot leans on its front
    • In our case, we used a cap nut at the end of our weapon's shoulder bolt to provide a smoother point of contact to lean on

• Electronics
  • Drive motors, esc, and receiver were used as provided
  • Weapon motor was a propdrive 1400KV driven by a 60A esc
    • This theoretically provided about 11000 RPM with a 63% spin-up time of about 1.118s

Positives

• Very powerful weapon assembly (possibly too much). Operated mainly at 30-50% max speed
• Bot could successfully operate inverted
• Weapon belt did not slip off of motor (but still slipped off of weapon)
• Tensioning slots on bottom plate allowed for easy belt tensioning adjustments
• Bolts through weapon speed holes worked as simple weapon locks

Issues

• Overall
  • Initial design very overweight: Compromises needed to be made for weight Savings
    • Removed Components:
      • Side Amor Plating; however, with the removal of Side Armor, leftover tabs became easy targets
      • Crossbars on Top & Bottom Plates
    • Cut-down Components:
      • Holes added to weapon
  • Poor Matchups
    • True undercutters
      • Can reach under wheel armor
    • Wedges
      • Not enough weapon bite or drive power to effectively combat wedges
    • Vertical/Drum Spinners
      • Having puzzle fit plates on the exterior provides vertical spinners with something to peel off of your robot

• Weapon
  • Belt slipped upwards off of weapon pulley
    • Possibly due to misalignment of the pulleys or an unevenly machined weapon pulley
  • Motor spec and pulley size provided too much RPM which could have been distributed to torque
    • Coupled with a poor drive system this resulted in very little bite

• Chassis
  • Very weak defenses all over
    • At our level of experience, defense should be prioritized over offense to ensure survivability
  • Other bots seem to prefer putting cap nuts on the top of the chassis
    • Cap nut increases the height of the weapon which is generally undesirable

• Drive
  • Hubs would not sit straight on motor shafts and drive would be uneven
  • Wheels were too close to chassis and would get caught sometimes
  • Poor control also possibly due to the center of gravity being so far away from the drive axis creating a greater moment

• Electronics
  • Scorpion Minis are not to be trusted all they do is short

Changes to make

• Have better defenses overall:
  • Thicker plates while ensuring the area where the motor connects to the wheel is thin enough
  • Thicker armor
  • Thicker screws
• Can save weight if needed by losing mass on weapon, specifically reducing the radius
• Make sure holes for motors align in side plates and bottom plate
• Make deeper pockets in the side plates to bring wheels out further from the robot
• Align pulleys better, make sure pulleys are smooth and deep enough to hold belts steady
• Only need 3-4 bolts on weapon to save weight
• Incorporated designated position for switch (Its cables are very stiff)

Velocitii (Version 2.0)

Created by: Jacques Wang, Austin Graves, Evan Strakes, Divyam Kumar, Bryce Parsons, Hanran Wu, and Brian Yang

Drive Motors	BotKits 22mm (The one they gave us)
Drive Motor Controllers	Scorpion Mini ESC (The one they gave us)
Weapon Motor	Propdrive v2 2836 1400KV Brushless Outrunner Motor
Weapon Motor Controllers	Turnigy Plush 32 60A Brushless Speed Controller
Receiver	HobbyKing HK-TR6A (The one they gave us)
Remote Control	The one they gave us
Battery	Turnigy nano-tech 1000mah 3S 45-90C Lipo (The one they gave us)

Design Summary

Velocitii was intended to be designed as a true undercutter however due to time constraints this was unable to happen. Velocitii is still a mid-cutter, however the weapon was still changed to a disk as with most undercutters and it lays a little lower to the ground than the average mid-cutter.

• Weapon
  • The weapon was completely redesigned and was changed to a 1/4 inch disk type weapon
  • A V-belt was used and 2 new pulleys were machined to go with it
• Chassis
  • The chassis was also remade to be stronger and more compact however the general puzzle fit shape still remained
  • We still implemented bent thin HDPE side armor, however this time it was designed to be secured onto the bot with 1/4-20 screws, which avoids the problem of having small stress concentrations around small screws and helps prevent the armor from being broken off unless the HDPE is completely compromised
• Drive
  • No changes were made to the drive except for the fact that we had to make bootleg wheels out of laser cut mdf since the shop ran out of 3 inch foam wheels
• Electronics
  • Mostly all the same, except we switched the weapon ESC to the Turnigy Plush as it was the smallest 60A ESC we could find

Positives

Velocitii only had 1 fight so theres not too much to say here

• The weapon was much less unwieldly when driving
• No electrical problems in combat
• V belt did not slip off pulleys

Issues

• Overall
  • We had little time to redesign and no time to order new parts/stock so we had to make do with what we could find and had to face down a steel weapon from 3/8 to 1/4
  • Weight was an issue as always but to be fair the wooden wheels and extra thick weapon disk added more than we had planned for

• Weapon
  • The new V belt design did not slip off but was poorly tensioned and stopped spinning up the weapon part way through the fight

• Chassis
  • Our HDPE armor was cut out with sharp angles and the stress concentration results in cracks along the corners

• Drive
  • Even worse than before due to the bootleg wheels not being tensioned tight enough on to the hubs resulting in slipping

• Electronics
  • Just like last time the electronics were just kind of thrown in there and were difficult to access and troubleshoot

Changes to make

Just like maybe test out your robot beforehand

Gallery

Velociti vs Mechanical Advantage Album Cover

Velociti Post-Chonkii

Velociti With Motorama Upgrades

Weapon Close Up

Notes:

Naming Inspiration: Sounded kinda cool I guess

Motorama judging system is rigged