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DRCSIM: five related questions to API and JointCommands

As a follow up to question 946 and new DRCSIM API http://gazebosim.org/wiki/DRC/UserGuide

The https://bitbucket.org/osrf/osrf-common/raw/default/ros/osrf_msgs/msg/JointCommands.msg shows terms for a standard PID + feedforward control policy.

1) Will the API allow resetting of the integral value? Preferably to an arbitrary value, and not just zero

2) How will the controller handle saturation?
(will there be integral tie back to prevent windup?)

3) What are the units of terms? (e.g. N*m, fraction max effort, ...).

The bitbucket link doesn't specify units, although I thought I saw N*m somewhere else.

4) Related to (2) and (3), will the individual actuator limits be published, or are we responsible for parsing the model definition file?

5) Will the jointCommands be issued in a vector to guarantee synchronous execution, or will the individual joint commands be sent separately? If latter, is there any way to guarantee coordinated execution?

The need for synchronous execution and potentially the need for a trajectory vector will depend on the answers to question 946 regarding update rate.