PIDController not manipulating jaguars

[gpetilli]

Originally Posted by vigneshv

It is a 6 wheel tank drive with the encoders on the gearbox. It just matters if the gears on either the left or right gearbox turn. Thanks!

Keep in mind that with tank drive, there is no way to protect against what I will call T-Bone. Your encoders wont move, and you have no torque in the X-direction anyway.

Are you using center drop wheel or are you using Omniwheels? If you are not using drop center wheels, I strongly recommend exactly two omnis (front or back) as a good compromise between turning ability and traction.

If you have left and right velocity PID loops to your gearbox encoders, it should allow the robot to old it's ground since any movement will be an error verses the commanded zero velocity. If the two loops act independently, they should also hold orientation. Any slop in your drive chain will limit your ability to sense movement and cause sensor delays (phase errors) which make the PID much harder to stabilize.

That said, we are finding that for external forces, the accelerometer works well for X and Y. For rotation, we are looking at the gyro.