Swivel Caster Ball Caster KoP WheelPlaction WheelOmni-Wheel Mecanum Wheel
simple rear wheel drive simple front wheel drive simple all wheel drive simple center drive 6 wheel drive tracked drive swerve/ crab drive other? 2WD4WD6WD Omni/Mecanum
The Good Cheap; Kitbot is 2WD Very simple to build The Bad Easily spins out Difficulty with inclines Loses traction when drive wheels leave floor
The Good More easily controlled Pretty simple to build Better traction The Bad Turning in place is more difficult Compromise between stability and maneuverability
Typically, one wheel is offset from the others to minimize resistance to turning Rocking creates two 4WD systems, effectively Typical offset is 1/8 – ¼ Rock isnt too bad at edges of robot footprint, but can be significant at the end of long arms and appendages One or two sets of omniwheels can be substituted for offset wheels.
Pushing power increased Mechanically more complicated Need to have adequate track tension Throwing a track and/or breaking one can be easy and very hard to fix Slower, much more power intensive Applications HEAVY duty pushing Climbing
Mechanically as complicated as a 4WD System A lot of times can substitute normal wheels for Omni/Mecanum in tight situations. Less pushing power, more maneuverable Control can be more complicated (especially with Mecanum) More parts that can break
Extremely mechanically and program complex Lots of parts to make/buy/fix Highly maneuverable Requires (normally) precise engineering Takes up a lot of space, uses a lot of motors Pure 4-Crab: 5 Pure 4-Swerve: 8!
Steering vs. Drive Systems In FRC, there are no Tank Drive Systems. There is Tank Steering and Track Drive Systems. These terms are NOT interchangeable. Tank Steering: Uses 2 Joysticks, Left Joystick controls speed of Left motors, Right Joystick controls speed of Right motors. Arcade Steering: Uses 1 Joystick, controls speed of Left and Right motors together.
1. Describe the Drive Train FRC Team #1208 (us…) used in the FRC 2010 Competition. 2. Name 1 advantage and 1 disadvantage of using a Meccanum Drive System. 3. What is the difference between Tank Steering and a Track Drive System?