parameter not declared in dwb_local_planner

[Marwan99]

https://github.com/ros-planning/navigation2/blob/a9171d0233de1aac5467cb0cf89adc1de0e73dfb/nav2_dwb_controller/dwb_core/src/dwb_local_planner.cpp#L175

< dwb plugin >.default_critic_namespaces parameter doesn't seems declared, does it need to be declared?

[SteveMacenski]

Can you explain the use of this? I don't actually see in the param file where this is used or how it might be used.

[Marwan99]

From my understanding <dwb plugin>.default_critic_namespaces param is expecting a vector of strings representing the namespaces that should include the critics defined in <dwb plugin>.critics param. The DWBLocalPlanner::resolveCriticClassName method resolves which critic plugin belongs to which namespace (this method implementation can potentially resolve to the wrong critic if two namespaces have the same critic name).

Currently <dwb plugin>.default_critic_namespaces is hard coded to ["dwb_critics"] as in here:
https://github.com/ros-planning/navigation2/blob/a9171d0233de1aac5467cb0cf89adc1de0e73dfb/nav2_dwb_controller/dwb_core/src/dwb_local_planner.cpp#L177

Since the <dwb plugin>.default_critic_namespaces param is not declared you can not amend this param from YAML .

I think the infrastructure to allow having critics from different namespaces is already in place, we just need to enable it through exposing the <dwb plugin>.default_critic_namespaces param by declaring it.

Does that sound right?

[Marwan99]

FYI, there is another parameter (<dwb plugin>.<critic name>.class) that is declared and read, which can be used to explicitly define the critic class name and namespace
https://github.com/ros-planning/navigation2/blob/a9171d0233de1aac5467cb0cf89adc1de0e73dfb/nav2_dwb_controller/dwb_core/src/dwb_local_planner.cpp#L190-L193

[SteveMacenski]

What's your suggestion? Just add a declare? That sounds reasonable.

[Marwan99]

Yeah pretty much.