Connection and Disconnection (LightBeam)

SUMMARY

Connect links a LightBeamSensor instance to an IsaacLightBeamSensor prim in the open Isaac Sim stage, and starts the simulation timeline. Disconnect releases that connection. All operations on the sensor other than connecting require an active connection, so always pair the two inside a try / finally block.

Available on: IsaacSim LightBeam.

The Skill

sensor.connect(simulation_prim_path="/World/simple_light_beam_sensor/LightBeam_Sensor")
sensor.disconnect()

The Code

"""
Demonstrates connecting to and disconnecting from a lightbeam sensor in a
running Isaac Sim stage.

Supports Isaac Sim only.

Usage:
    python connection_and_disconnection.py --prim_path <PRIM_PATH>
    python connection_and_disconnection.py --prim_path <PRIM_PATH> --load_usd

Note:
    Open Isaac Sim and add a lightbeam sensor prim before running this. If
    there is none in the stage yet, follow
    https://docs.isaacsim.omniverse.nvidia.com/5.1.0/sensors/isaacsim_sensors_physx_lightbeam.html
    to create one, or pass --load_usd to add one to the open stage -- this
    keeps whatever is already in the stage.
"""

import argparse

from loguru import logger

from telekinesis.medulla.sensors import isaacsim


def main(prim_path: str, load_usd: bool) -> None:
    """Connects to a lightbeam sensor, then disconnects."""

    if load_usd:
        # ===================== Load Demo Scene (Optional) ===========================
        from telekinesis import datatypes, isaacsim_client

        client = isaacsim_client.IsaacSimClient(
            api_key="",
            base_url="http://127.0.0.1:8766",
            websocket_base_url="ws://127.0.0.1:8766",
        )
        asset = datatypes.USD.from_url(
            "https://assets.telekinesis.ai/usd/sensors/simple_light_beam_sensor.zip"
        )
        client.stage.add_to_scene(uri=asset.path.as_posix(),
                                  prim_path="/World/simple_light_beam_sensor")

    # ===================== Create Sensor ======================================
    sensor = isaacsim.LightBeamSensor(name="my_simulated_lightbeam")

    try:
        # ==================== Run Skill ============================================
        sensor.connect(simulation_prim_path=prim_path)
        logger.success(f"Connected: {sensor.is_connected}.")
    except (ConnectionError, RuntimeError) as e:
        logger.error(f"Error occurred: {e}")
    finally:
        sensor.disconnect()


if __name__ == "__main__":
    p = argparse.ArgumentParser(
        description="Connect to and disconnect from a lightbeam sensor in Isaac Sim")
    p.add_argument(
        "--prim_path",
        type=str,
        default="/World/simple_light_beam_sensor/LightBeam_Sensor",
        help='Isaac Sim lightbeam sensor prim path, e.g. '
        '"/World/simple_light_beam_sensor/LightBeam_Sensor"')
    p.add_argument("--load_usd", action=argparse.BooleanOptionalAction, default=False,
                   help="Add the bundled demo lightbeam sensor to the open "
                        "stage at /World/simple_light_beam_sensor before "
                        "connecting. Use this if you don't already have one "
                        "in the stage.")
    args = p.parse_args()

    main(prim_path=args.prim_path, load_usd=args.load_usd)

Running the Example

python connection_and_disconnection.py --prim_path /World/simple_light_beam_sensor/LightBeam_Sensor

To load the bundled demo sensor into the stage first:

python connection_and_disconnection.py --load_usd

For all options:

python connection_and_disconnection.py --help

Parameter Configuration

connect

Parameter	Type	Default	Description
simulation_prim_path	str	required	USD path of an IsaacLightBeamSensor prim in the open Isaac Sim stage, e.g. "/World/simple_light_beam_sensor/LightBeam_Sensor".

disconnect

Takes no parameters.

Returns

Method	Type	Description
connect	None	Returns nothing.
disconnect	None	Returns nothing.

Raises

Method	Exception	Condition
connect	RuntimeError	The sensor is already connected, or the connection fails (Isaac Sim not running with the telekinesis.isaacsim.bridge extension enabled, or the prim missing from the stage).
connect	TypeError	simulation_prim_path is empty or not a string.
disconnect	(none)	Calling on a sensor that is not connected logs a warning instead of raising.

Where to Use the Skill

Connect is the first call against a LightBeamSensor, and Disconnect the last. Use Is Beam Broken in between to read the sensor.