Description
To run:
roslaunch dave_demo_launch dave_manipulator_spring_demo.launch
roslaunch dave_demo_launch dave_manipulator_spring_plot.launch
In the below example, the plotting function is showing the shoulder joint.
Observed Issue:
Oberon7 arm with ft_sensor shows what appears to be noise when plotting joint torques during manipulator operation.
| Rexrov with Oberon7 | Shoulder Z torque when moving |
|---|---|
 |
 |
Without Joint Controller
By removing the joint controller, we see that the ft_sensor generates less "noisy" data and responds reasonably to contact with the environment. However, there are edge cases.
| Rexrov with Oberon7 and no controller |
|---|
 |
By moving the rexrov up and down we see the arm's shoulder torque changing in correspondence. As well, there is some high frequency oscillation that only occurs when the ROV is not moving. The working theory is that it is caused by the arm bouncing off of the ROV body as there is no controller force to hold it up.
Controller Tuning
We find PID values related to the control of the oberon7 in two locations: oberon7_control/launch/joint_control.launch and oberon7_control/launch/joint_effort_controllers.launch
Tuning attempts are ongoing. Initial iterations are based on changing PID values for each joint until oscillations discipate, then moving on to the next joint.