[ROS2] Watchdog trips on LoveLace during service calls

[amalnanavati]

Sometimes on LoveLace, in the process of all the service calls in pre_moveto_config (i.e., toggle watchdog listener off, re-tare FT sensor, toggle watchdog listener on, and set FT thresholds) the watchdog trips because a watchdog message hasn't been received in 0.5 sec (or 0.1, depending on the parameter setting). However, the update function of that behavior is async, so it should not be blocking. This is something that is necessary to look into -- why sometimes watchdog messages are not received for a time period. It may be related to #62 , or to this article on deadlock.

Note that both LoveLace and Nano are using Cyclone DDS

[amalnanavati]

Note that this is not an issue on t0b1 + nano -- not sure what is going on with lovelace...

[amalnanavati]

It is also worthwhile considering moving the setup function for the tree (in create_action_servers.py) to only run once when the tree is created, not at the beginning of every action call.

[amalnanavati]

It is also worthwhile modifying the the service and action in py_trees_ros such that if the wait time is 0.0, it just checks whether the server is ready as opposed to waiting for it. (although then is there any point to that call? 🤷‍♂️)

[amalnanavati]

#92 mostly addresses this, lingering issues will be documented there.

[amalnanavati]

NOTE: The other thing (In addition to #92 ) that may have helped with this issue is lowering the face detection rate to 3Hz (in #91 ), because face detection eats up a lot of CPU power.

[amalnanavati]

This issue has stopped occuring after #92 and #94 got merged in.