Set Force

SUMMARY

Set Force configures the default gripping force. Call set_force only when a different session-level default is needed.

SUPPORTED GRIPPERS

Available on Robotiq (force in the configured unit, default percent) and OnRobot grippers (force in N, clamped to model max).

UNITS

force in the configured force unit (default percent for Robotiq, N for OnRobot).

The Skill

actual_force = gripper.set_force(force=60.0)

The Code

Example: Set a Session-Level Force Baseline

"""
Robotiq 2F-85 set default grip force example for the Synapse SDK.

Sets the default grip force used by subsequent open/close/move calls.
Value is a percentage of the gripper's max force.

Usage:
    python set_force.py --ip <ROBOT_IP>
"""

import argparse
from loguru import logger

from telekinesis.synapse.tools.parallel_grippers import robotiq


def main(ip: str):
    """Set the gripper default grip force to 50%."""

    # Create and connect to the gripper
    gripper = robotiq.Robotiq2F85()
    gripper.connect(ip=ip)

    try:
        actual = gripper.set_force(force=50.0)
        logger.success(f"Default force set; effective: {actual}")
    finally:
        gripper.disconnect()


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Robotiq gripper set_force example")
    parser.add_argument("--ip", type=str, required=True, help="UR robot IP address")
    args = parser.parse_args()

    main(ip=args.ip)

The Explanation of the Code

set_force stores a session-level default force. It applies to subsequent move, open, and close calls when those calls pass force=-1.0. The method returns the actual force value accepted by the backend.

Default. After connect, the force is automatically set to 100% in percent units. Only call set_force to change this default.

Force unit. Force is expressed in the unit configured by set_unit("force", ...) (default: "percent" after connect, range 0-100).

-1.0 preset passthrough. Passing -1.0 instructs the backend to keep its current internal preset without overriding it from software.

Return Value

Type	Description
float	The actual force value accepted by the backend.

How to Tune the Parameters

Robotiq 2F-85

Parameter	Type	Description
force	float	Desired force in percent (0-100). Pass -1.0 to use the backend's current preset.

OnRobot RG2 / RG6

Parameter	Type	Description
force	float	Desired force in Newtons. RG2 max 40 N, RG6 max 120 N. Pass -1.0 to use the backend's current preset.

TIP

Start with a low force (20-30% for Robotiq, or ~10 N for OnRobot) for lightweight or fragile parts and increase until the grasp is secure without risking damage.

Where to Use the Skill

• Session baseline - Set once after connecting so individual move/open/close calls can pass force=-1.0
• Force profile switching - Re-call mid-session when switching between object types that need different gripping forces

When Not to Use the Skill

Do not call set_force when:

• Force is passed per-call - if every move/open/close already includes an explicit force argument, this call is redundant
• The gripper is not connected - always call connect before issuing configuration commands