pic: Team Unlimited's Gear Shifter

This is a picture of the chassis that Team Unlimited actually used in competition for the FIRST Vex Challenge for the 2006-2007 season. This is the original chassis, it changed a little after that picture was taken. If you want more information on how we made this gear shifter, you can find the information on our website at: http://eaglevex.syraweb.org/GearShifter.htm
There are gear shifter renders there at show the shifter in Maya 8, the text on that page will explain how we made this shifter, and how it works.
If you are interested in this, feel free to explore our site: http://eaglevex.syraweb.org/
Team Unlimited would like to wish the best of luck to all FIRST teams for the coming competition season!
~ FTC 1, Team Unlimited

P.S. If you have any questions, feel free to contact the team through the site, or email me, PM me, AIM me, or MSN Messenger me. BEST OF LUCK TO EVERYONE!

Just a few questions about your gearbox and chassis design:

  • Is there a tendency for the gears to get stuck while switching gears in motion?
  • While it’s stationary?
  • Are there ever issues with the chains on the sides falling off or becoming jammed? (Especially if hit by objects, like the rings or other robots.)
  • What is the purpose of the omni-wheels? It looks like they are suspended in mid-air and aren’t actually used to support or drive the robot.
  • Is it necessary to have 2 motors per side?

Since it’s not single-design oriented, I believe I can answer the motors per side question.

Certain teams might not find it necessary to have 2 drive motors per side. However when you weigh the entire robot down with steel manipulator parts, if you’re geared for speed you’ll definitely notice lackluster power due to the extra mass. In other words it will take (seemingly) forever for the bot to get up to speed.

If you have a very lightweight bot or it’s only geared for med-high torque situations (therefore low speed) you could probably get away with 1 motor per side.