CeRVaNTeS' arm and base control (maxon+epos2)
From robotica.unileon.es
Maxon motors arm and base
The drives of the arm and base are compound by the elements shown below:
Arm
- Shoulder (turn/tilt) = 2 motorsMaxon RE 30 (60W) + 2 Epos2 controllers + 2 Planetary Gearheads 246:1 + 2 incremental encoders 1024cpt
- Elbow (turn/tilt) = 2 motors Maxon RE-max 29 (22W) + 2 Epos2 controllers + 2 Planetary Gearheads 246:1 + 2 incremental encoders 1024cpt
- Wrist(turn) = 1 motor Maxon A-max 22 (6W) + 1 controller Epos2 + 1 Planetary Gearhead 270:1 + 1 incremental encoder 1024cpt
- Wrist (tilt/inclination) = 2 motors Maxon EC 20 flat (5W) + + 2 Epos2 controllers + 2 Planetary Gearheads 270:1 + sensor Hall 16cpt
Note: There is a potentiometer in each joint of the arm connected to Gearhead's output in order to know the absolute position of the arm joints.
Base
- Base (left/right wheel) = 2 motors Maxon RE-max 29 (22W) + 2 Epos2 controllers + 2 Planetary Gearheads 86:1 + 2 incremental encoders 2048cpt
Note: The Epos2 controllers are connected to a CANopen bus, each controller have a unique ID. The PC is plugged to USB port of the initial controller and it works like master.
ROS y Epos2
We have based on wpi-rover project to realize the driver for the communication between ROS and the Maxon's Epos2 controllers. This project consists of a ROS wrapper or package that uses the Epos2's linux libraries.