Connection and Disconnection (CNC)

SUMMARY

Connect links a CNCMachine instance to a door prim in the open Isaac Sim stage, together with the open and closed positions the door travels between. Disconnect releases that connection. All operations on the door other than connecting require an active connection, so always pair the two inside a try / finally block.

Available on: IsaacSim CNC.

The Skill

machine.connect(simulation_prim_path="/World/cnc_machine/E_body_1/door",
                open_position=(-0.687, -0.053, 1.208),
                closed_position=(-0.219, -0.053, 1.208))
machine.disconnect()

The Code

"""
Demonstrates connecting to and disconnecting from a CNC machine's door 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 CNC machine whose door is its own prim before
    running this, or pass --load_usd to add one to the open stage -- this
    keeps whatever is already in the stage. Both positions are relative to
    the door prim's parent: select the door prim, slide it fully open and
    fully closed in the stage, and read the position off Property >
    Transform each time. Where that transform is shown as a matrix, the
    first three values of the bottom row are its x, y and z.
"""

import argparse

from loguru import logger

from telekinesis.medulla.machines import isaacsim


def main(prim_path: str,
         open_position: list[float],
         closed_position: list[float],
         load_usd: bool) -> None:
    """Connects to a CNC machine's door, 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/machines/cnc_machine.zip"
        )
        client.stage.add_to_scene(uri=asset.path.as_posix(),
                                  prim_path="/World/cnc_machine")

    # ===================== Create Machine =======================================
    machine = isaacsim.CNCMachine(name="my_simulated_cnc_machine")

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


if __name__ == "__main__":
    p = argparse.ArgumentParser(
        description="Connect to and disconnect from a CNC machine's door in Isaac Sim")
    p.add_argument("--prim_path", type=str, default="/World/cnc_machine/E_body_1/door",
                   help='Isaac Sim CNC machine door prim path, e.g. '
                        '"/World/cnc_machine/E_body_1/door"')
    p.add_argument("--open_position", type=float, nargs=3,
                   default=[-0.68654, -0.05313, 1.208], metavar=("X", "Y", "Z"),
                   help="Door position in meters, relative to the door "
                        "prim's parent, at which it stands open")
    p.add_argument("--closed_position", type=float, nargs=3,
                   default=[-0.2193, -0.05313, 1.208], metavar=("X", "Y", "Z"),
                   help="Door position in meters, relative to the door "
                        "prim's parent, at which it stands closed")
    p.add_argument("--load_usd", action=argparse.BooleanOptionalAction, default=False,
                   help="Add the bundled demo CNC machine to the open stage "
                        "at /World/cnc_machine before connecting. Use this "
                        "if you don't already have one in the stage.")
    args = p.parse_args()

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

Running the Example

python connection_and_disconnection.py --prim_path /World/cnc_machine/E_body_1/door

To load the bundled demo CNC machine 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 the door prim of a CNC machine in the open Isaac Sim stage, e.g. "/World/cnc_machine/E_body_1/door".
open_position	Sequence[float]	required	Position (x, y, z) in meters, relative to the door prim's parent, at which the door stands open.
closed_position	Sequence[float]	required	Position (x, y, z) in meters, relative to the door prim's parent, at which the door stands closed.

disconnect

Takes no parameters.

Returns

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

Raises

Method	Exception	Condition
connect	RuntimeError	The machine 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.
connect	ValueError	Either position is not three coordinates.
disconnect	(none)	Calling on a machine that is not connected logs a warning instead of raising.

Where to Use the Skill

Connect is the first call against a CNCMachine, and Disconnect the last. Use Open and Close Door in between to drive the door.