Monday, 9 September 2013

First arm test

Just a quick video of the right arm, testing the shoulder tilt and lift motors. The good news is it held up and nothing broke or burnt out the lift motor only goes up half way  at the moment I have to reset the pot zero and change the start point and adjust the PID controller for the weight of the arm but the speed of the lift is good and the tilt is a bit slow I have to change the gear ratio from 3:1 to 2:1 but that is for the next model actuator. Part of the test was to compare directions of the real robot to the model in RVIZ the tilt axis is reversed and lift is going the right way and the angles look close next test will be with all the servos and the lift with full travel.
The base is not very stable but the new base is almost finished and is shown in the model in RVIZ

Sunday, 1 September 2013


It's been a hard couple of weeks the new base needs a wider foot print it's not very stable when moving making the kinect laser scan is unreliable but the worst part was the new dog wanted to say hello by jumping up on him which resulted in Robbie falling over the good part was most of the upper torso was off so very little damage was done. With the battery charger on board and hooked to the battery all the time this discharges the battery when not in use for a while. So after a bit of a rethink I I'm rebuilding the drive base with bigger wheels a wider base and better weight distribution also added a charge bar so charging can be done from a docking station.
 Finally had so time to play with arms today  I was really happy with the moving the shoulder lift( the joint with the most strain) was moving nice and smooth through the full range of movement but when I tried a fast full range movement the drive coupling broke again if I could join the 2 STL file's (Freecad just crashes) I would print them in nylon