Isaac Sim: Check which object collided with obstacle

Hello there,
I have multiple robots moving around in my scene and there is one obstacle (mesh). I now want to check at each physic step if there was a collision with the obstacle. If so, then I want to know which robot collided with the obstacle.

What is the best way to add some kind of collision checker to my obstacle to find out if/which of my robots collided with it? I am using the python API, any help is highly appreciated!

Thank you in advance!

Take a look at the Isaac Contact Sensor Isaac Sensor — Omniverse Robotics documentation

If there is another way I would be happy to hear about it.

Usage example:

class ContactForceSensor:
    def __init__(self, sensor_prim_path, stage, robot_view: ArticulationView):
        # TODO(review): remove useless arguments from init (do not know why by **kwargs did not work)
        self. sensor_prim_path = sensor_prim_path
        self._cs = _isaac_sensor.acquire_contact_sensor_interface()
        color = (np.random.rand(), np.random.rand(), np.random.rand(), 1)
        # Note: When calling directly the function IsaacSensorCreateContactSensor the force generated seems to be zero

    def get_body_paths_in_contact(self) -> Set[str]:
        # Return a set of body paths in contact with the current sensor
        body_paths = set()
        raw_sensor_data = self._cs.get_contact_sensor_raw_data(self.sensor_prim_path)
        # Return a void set if there is no contact
        if len(raw_sensor_data) == 0:
            return body_paths
        # Loop of the contact body names (encoded)
        for body_raw in raw_sensor_data["body0"]:
            # Decode the body in contact to get the path
            full_body_path = self._cs.decode_body_name(body_raw)
            # Get the path of the object but not its child link
            # e.g. Get /World/envs/env_*/block02_0 rather than
            # /World/envs/env_*/block02_0/block_2_base_link
            body_path = "/".join(full_body_path.split("/")[:5])
        return body_paths

Thank you very much for your reply @loic.sacre ! I will take a look into the contact sensor, but intuitively it seems like more overhead than necessary to simulate a sensor. And especially with complex shaped robots, it could be rather difficult to get accurate collision feedback like this, without having to add dozens of sensors.
I looked into some other methods such as overlap_mesh from omni.physx.get_physx_scene_query_interface but they only seem to work for cubes and spheres. If anybody has used these methods for more than a cube, I would really like to hear about it.