Telekinesis Agentic Skill Library

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Gripper Get Current Position ​

SUMMARY

Get Current Position reads the current finger separation of the gripper in the configured position unit (default: millimeters).

UNITS

Returns finger separation in the configured position unit (default mm after connect).

The Skill ​

python
position = gripper.get_current_position()

The Code ​

Safety first!

A real robot will faithfully do whatever you ask of it - so please take a moment to clear the workspace, keep an E-Stop within reach, and be ready to disconnect.

Operating real hardware is at your own risk.

python
"""
Demonstrates reading the current position of a parallel gripper.

Supports OnRobot and Robotiq grippers, and Isaac Sim.

Usage:
    python get_current_position.py --ip <GRIPPER_IP>
    python get_current_position.py --prim_path <PRIM_PATH>

Note:
    Experimental gripper support for Isaac Sim:  Robotiq 2F85 (USD-based simulation only); Schunk EGP and
    PZN+ are.
"""

import argparse
from loguru import logger

from telekinesis.synapse.tools.parallel_grippers import onrobot


def main(ip: str | None,
         protocol: str,
         prim_path: str | None) -> None:
    """Reads the current position of an OnRobot gripper in the configured unit."""

    #===================== Create Gripper ======================================
    gripper = onrobot.OnRobotRG6()

    try:
        #===================== Connect Gripper =================================
        if prim_path:
            gripper.connect(simulation_prim_path=prim_path)
        else:
            gripper.connect(ip=ip, protocol=protocol)

        # ==================== Run Skill ====================================
        logger.success(f"Current position: {gripper.get_current_position()}")
    except (ConnectionError, OSError) as e:
        logger.error(f"Error occurred: {e}")
    finally:
        gripper.disconnect()


if __name__ == "__main__":
    p = argparse.ArgumentParser(description="OnRobot gripper get current position")
    p.add_argument("--protocol",
                   choices=["MODBUS_TCP"],
                   default="MODBUS_TCP")
    p.add_argument("--ip", default=None, help="IP for OnRobot Gripper")
    p.add_argument("--prim_path", type=str, default=None,
                   help='Isaac Sim gripper prim path, e.g. "/World/onrobot_rg6"')
    args = p.parse_args()

    main(ip=args.ip,
         protocol=args.protocol,
         prim_path=args.prim_path)

Running the Example ​

bash
python get_current_position.py --ip 192.168.1.100
bash
python get_current_position.py --prim_path /World/onrobot_rg6

For all options:

bash
python get_current_position.py --help

Parameter Configuration ​

This skill takes no input parameters.

Returns ​

TypeDescription
floatCurrent finger separation in the configured position unit.

Raises ​

ExceptionCondition
RuntimeErrorThe gripper is not connected

How to Tune the Parameters ​

Compare the returned position against a threshold rather than an exact value - hardware-level variation means the reading will vary slightly between calls.

Where to Use the Skill ​

  • Grasp verification - Confirm an object is held before transporting
  • State inspection - Read gripper position at any point in a workflow for logging or branching logic
  • Closed-loop control - Combine with move to implement position-feedback loops

When Not to Use the Skill ​

Do not use Get Current Position when:

  • The gripper is not connected - always call connect before issuing gripper commands
  • High-frequency polling is required - repeated queries add latency; use asynchronous motion and a single readback instead