Types of Drives?

[Frank(Aflak)]

Originally posted by RogerR
there was a large debate (over the summer, i think) in which it was determined that crab and swerve drive lack the three degrees of freedom required to be a true 'omni-directional drive'; they only have two, rotation and x-direction.

a killough(sp?) platform or 'holonomic drive' has three degrees of freedom, and therefore is a 'true' omni-directional drive.

old thread on the subject

the first FIRST killough platform (i believe) was built by team 857 in 2002, and was called the 'kiwi-drive'.

If we can get ahold of (raise the money to buy) quality omniwheels we are going to use a four-wheel Killough variant (wheels 90 degrees apart instead of 120 degrees apart).

Its been worked on, and should actually be mechanically simpler and much more robust than last year's drive. Of course, we will only go ahead if it is consistant with our strategy, which will be decided come January.

The programming will be tough, but thats not my deptartment (i'm just the lead designer). Control should be a breeze. If we manage to get the solid-state gyro online enough to give us a consistant heading so that pushing the joystick north, regardless of the facing of the robot, will cause the robot to move north. and same with all the other directions. With a twist-stick joystick, we can add translational and rotational movement all into one hand . . . it is a good plan, I think. We will see. The biggest problem will be to make the chips and drills run at the same speed not only at 100% throttle, but at all the various percentages in between. Like I said, we will see how things go.