Monday, 25 February 2013

New Shoulder and Torso

While waiting for the bearings for the wave generator I tried out the harmonic joint in the new torso. The torso will be able to raise 30cm. The weight of the motor helps to balance the weight of the arm

now I just have to add the lift actuator there’s a lot of wasted space with the wood form work

Sunday, 24 February 2013

Harmonic Drive 2

After Robbies shoulder gear failed with a broken tooth I stepped up work on the harmonic drive I have a first draft model for engineering fits and clearance. The flex
spline proved the hardest part to print I had to change the print setting until i got a good print I'm still waiting for the bearings for the wave generator so i can start testing

 A mixture of files some mine and most from

 Slowly starting to get the hang of CAD

A broken tooth this part in the shoulder lift joint has the most force applied

Friday, 22 February 2013

Harmonic Drive

Well it's be a while since the last update after the holidays they a quick trip overseas
it time to get back to work. Robbies shoulder lift joint now works the PID controller works under load. The problem was the arduino was doing to much 2 PID controllers and 4 servos was to much so now I’m just going to use one arduino per joint and communication will be do with I2C. Using the toner transfer method I can make the PCB's required for a good price. That just leaves the gear box's going to try using a harmonic gearbox from thingiverse 16:1 reduction should give enough torque.

The ROS drive now publishes motor states and a Joint_state publisber now publishes all the joints and the dynamixels as well