Error in state validation Isaac flatsim

I have been experimenting with the Isaac flatsim DifferentialBaseSimulator . I am using goal behavior : pose. I set a goal in the Isaac sight. It throws up this error (I don’t see the lidar points that I used to see earlier).

2021-04-12 12:50:58.398 ERROR packages/trajectory_validation/components/TrajectoryValidation.cpp@256: 
Collision check has failed. The trajectory is not valid.
2021-04-12 12:50:58.441 ERROR external/com_nvidia_isaac_engine/engine/alice/components/Codelet.cpp@229: Component 'flatsim.navigation.control.state_validation/StateValidation' of type 'isaac::trajectory_validation::StateValidation' reported FAILURE:

    Collision check has failed. Stopping the robot.

What could be the source of this problem? I am using the flatsim package, so the lidar scan generation is automated right?


The first thing you should check is the coordinates where your robot is being spawned. It could be that the initial pose of your robot is not a valid coordinate in the map, meaning that the robot is being spawned at an obstacle.

If that does not work, in isaac-sdk/sdk/packages/navigation/apps/differential_base_control.subgraph.json, find the trajectory_validation section and edit the CollisionCheck object by customizing the deceleration_limit or distance_treshold.

It could also be that if you have created your own obstacle, if that’s the case, you should add it to trajectory_validation\obstacle_names.

Hope that works!

Yes, I noticed that whenever the robot spawns on an obstacle region it pops up the collision check. I set a different init pose and I don’t have the error anymore.
But there are other times either when the robot somehow thinks it is on an obstacle or when the lidar rays disappear this behavior is exhibited too. Any ideas on that?