Robotiq 3F Gripper — ROS 2 Control Guide

Control the Robotiq 3-Finger gripper over Modbus TCP using the ROS 2 action server and service interface.

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Table of Contents

• Setup & Launch
• Control via Action: gripper_cmd
• Change Grasping Mode: change_grasping_mode
• CLI Quick Reference
• Parameter & Value Reference

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Setup & Launch

Launch the driver with your gripper IP

ros2 run robotiq_3f_ros2_driver gripper_action_server \
  --ros-args -p gripper_ip:=<YOUR_GRIPPER_IP>

Example:

ros2 run robotiq_3f_ros2_driver gripper_action_server \
  --ros-args -p gripper_ip:=192.168.1.11

Default IP: 192.168.1.11 · Modbus port: 502 · Unit ID: 9

Or use the launch file

ros2 launch robotiq_3f_description robotiq_3f_gripper.launch.xml

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Control via Action: gripper_cmd

Action type: control_msgs/action/GripperCommand
Action name: /gripper_cmd

Blocks until the gripper reaches the target or times out (10 s).

Goal fields

Field	Type	Range	Description
command.position	float64	0.0 – 0.155 m	0.0 = fully closed, 0.155 = fully open
command.max_effort	float64	0.0 – 70.0 N	Max force. 0.0 uses a safe internal default

Result fields

Field	Type	Description
reached_goal	bool	true if gripper reached target or detected contact
position	float64	Echoes the commanded position

Position reference

position (m)	Gripper state
0.0	Fully closed
0.077	Half open
0.155	Fully open

Force reference

max_effort (N)	Behaviour
0.0	Gentle (safe default — 50/255 internally)
35.0	Medium force
70.0	Maximum force

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Change Grasping Mode Service

Service type: robotiq_3f_interfaces/srv/ChangeGraspingMode
Service name: /change_grasping_mode

Request

Field	Type	Description
mode.mode	int8	Mode integer (see table below)

Response

Field	Type	Description
success	bool	true if mode changed successfully

Grasping modes

mode	Name	Best for
0	BASIC	General grasping (default)
1	PINCH	Small or thin objects
2	WIDE	Large or bulky objects
3	SCISSOR	Independent scissor / lateral control

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CLI Quick Reference

Gripper movement

# Open fully
ros2 action send_goal /gripper_cmd \
  control_msgs/action/GripperCommand \
  "{command: {position: 0.155, max_effort: 0.0}}"

# Close fully (medium force)
ros2 action send_goal /gripper_cmd \
  control_msgs/action/GripperCommand \
  "{command: {position: 0.0, max_effort: 50.0}}"

# Half open
ros2 action send_goal /gripper_cmd \
  control_msgs/action/GripperCommand \
  "{command: {position: 0.077, max_effort: 30.0}}"

Grasping mode

# Basic (default)
ros2 service call /change_grasping_mode \
  robotiq_3f_interfaces/srv/ChangeGraspingMode "{mode: {mode: 0}}"

# Pinch
ros2 service call /change_grasping_mode \
  robotiq_3f_interfaces/srv/ChangeGraspingMode "{mode: {mode: 1}}"

# Wide
ros2 service call /change_grasping_mode \
  robotiq_3f_interfaces/srv/ChangeGraspingMode "{mode: {mode: 2}}"

# Scissor
ros2 service call /change_grasping_mode \
  robotiq_3f_interfaces/srv/ChangeGraspingMode "{mode: {mode: 3}}"

Inspect

ros2 action list
ros2 service list | grep gripper

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Parameter & Value Reference

Modbus connection

Parameter	Value
Default IP	192.168.1.11
Port	502
Unit ID	9
Status poll interval	0.1 s

Object detection status (gDTA)

Value	Meaning
0	Moving
1	Stopped — contact while opening
2	Stopped — contact while closing ✓
3	Stopped — reached requested position ✓

Action server marks success on gDTA == 2 or gDTA == 3.

GraspingMode constants (Python)

from robotiq_3f_interfaces.msg import GraspingMode

GraspingMode.BASIC    # 0
GraspingMode.PINCH    # 1
GraspingMode.WIDE     # 2
GraspingMode.SCISSOR  # 3

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Package Structure

robotiq_3f_modbus/
├── robotiq_3f_interfaces/       # Messages and services
│   ├── msg/
│   │   ├── GraspingMode.msg
│   │   ├── SimpleControlCommand.msg
│   │   ├── IndependentControlCommand.msg
│   │   ├── ObjectDetectionStatus.msg
│   │   └── Status.msg
│   └── srv/
│       └── ChangeGraspingMode.srv
├── robotiq_3f_ros2_driver/      # Driver node
│   └── robotiq_3f_ros2_driver/
│       ├── gripper_action_server.py
│       ├── test_gripper_client.py
│       └── robotiqcontrol/
│           └── GripperController.py
└── robotiq_3f_description/      # URDF and launch files
    └── launch/
        └── robotiq_3f_gripper.launch.xml

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Robotiq 3F · ROS 2 · Modbus TCP · BSD-3-Clause