Higher preference for backward movements in TEB+SBPL

[nitin5]

Greetings,
I am trying to setup sbpl+teb in stage simulation setup. I am using cfg/diff_drive configuration files as supplied with the code.
I found that robot has higher preference for making backward movements to align robot along the planned global path. Even in place rotation is not prefered for differential drive robot.

I have tried changing the parameter weight_kinematics_forward_drive to higher value. This influences trajectory selection but robot still makes in place back ward movements to correct its heading.

I have also observed that robot gets stuck in a loop at tight places to achieve its goal configuration.
Is this behaviour expected? If not, how can I improve it.

Thanks
Nitin

[nlimpert]

Hi, sorry for the late response.
Did you try to tweak the max_vel_{x,y, theta} values? The teb_local_planner seems to prefer directions that allow a faster velocity.
You might also want to try out setting up the global_plan_viapoint_sep parameter of teb_local_planner in order to "force" the teb_local_planner to follow the global plan.

Unfortunately we face the same problems in tight spaces with ackermann driven robots. Maybe tweaking the said parameters (max_vel_*) might help you or the teb_local_planner, respectively to select proper trajectories even in tight environments.