Localization / Odometry using omnidirectional wheels (or Killough Platform)

Jan 18, 2006 1 Replies

Hi,



I want to create a robot using a killough platform and keep track of its position so that I will travel a certain point and return back to its home. Is there any documentation on odometry, etc using a killough platform or omnidirectional wheels???


Thanks,


Ram



PS: Code will be great too!!!



Hey, I just finished building one of those! My idea was to have a platform able to track a flashlight beam, keeping it centered in the center of a photodetector array. I gotta tell you, the motion is not straight line and smooth, in certain directions the small friction in the non-driven axes throws off the trajectory. I am running on carpet, you might do better on a smooth floor.

Anyway, if you know the direction of the commanded velocity, the individual motor commands are all K*sin(some combination of command vector angle and fixed motor axis angle). I also have C code written for an AVR processor, which uses 3 PWM signals for positive commanding, and 3 more for negative commanding.

The sensitivity of the motion to the commands means you will probably have to run your motors with closed loop feedback. I used home-made encoders. I tried open loop, but each motor has different friction characteristics.

Anyway, email me and I will dump more on you than you probably want.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required