1 | initial version |

Thank you fro responding !The vehicle drifts with each circle it executes . I will post some of the code changes I made . I did notice that the Carbot example with Ros executes a perfect circle repeatably.

2 | No.2 Revision |

Thank you ~~fro ~~for responding ~~!The ~~!

**I have solved this the vehicle drifts with each circle it executes drift issue .. a few points**
1. Had the rear wheels turning. Fixed that
2. Calculated inner and outer wheel angles based on Ackerman and fixed them as limits.
2. In order to test this without a closed loop I provided steering and gas continuously and calculated the radius of curvature for 0.1 and 0.2 radians s = wheel base a = steering wheel angle n = steering ratio (e.g. for 16:1, n = 16) r = radius of curvature, in the same units as the wheel base So: r = s / (sqrt(2 - 2 * cos(2*a/n)) . I

Further work .... 3. To test further I have to use a PID controller. 4. Must also eliminate arbitrary empirical constants like sway force , aero dynamic etc and get a more first principles approach 5. The input angle has to be rate limited ..

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