Localization / Odometry using omnidirectional wheels (or Killough Platform)

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!!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@olf.com wrote:

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.
--
Mike Ross
The instructions said use Win98 or better, so I used Linux.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.