First Printed Parts

Its been awhile since the last post the printer is finished and working
the threaded rods i use for the X and Y axis make the printer very slow, but at least it works. To use the printer to its full potential I need to learn cad and openscad which all takes time the first parts are starting to find there way
on the robot the orings i used to sync the castor angle and potentiometer didn't last long and tended to slip off, replacing them with gears seams to be a natural choice the only snag is reverse the pot power connections  to make up for the change in direction when using gears. I mover the MCU from the side pod
to under the torso (which has been hinged to provide quicker access). The wiring has also been cleaned up to provide better reliability. I finally completed the drive motors by adding the last motor controller and encoders now its a true holomonic drive, but i fear we have run up to the limit of the AtMega I'm having a lot of trouble tuning the PID loops (8) stearing works fine on it's own but when i  add the drive velocity control  the steering starts to drift

Steering Update

After a week off driving and testing most things work as expected crab steering works well with the potentiometers limit of 300 deg and no reverse drive at the moment being the main limit Ackerman steering works to about 22 deg off center, but spin in place results in skidding of the wheels. With the above in mind I changed the steering to independent 4 wheel steering and drive