OnRobot ROS 2 Controller

Introduction

ROS 2 drivers for OnRobot Grippers. This repository was inspired by Osaka-University-Harada-Laboratory/onrobot.

The current build of this package only supports the OnRobot RG series, only tested on the OnRobot RG6 gripper. The package supports various control methods, like physical device control via Modbus, or simulated gripper either by self-simulation, or leveraging Isaac Sim's simulation environment.

Features

• Ubuntu 22.04 PC
• ROS 2 Humble (Python3)
• Controller for OnRobot RG2 / RG6
  • Modbus TCP/IP
  • Simulated (WIP)
  • Isaac Sim
• CLI controller
• Width / Height / Joint value cross calculation service
• GripperCommand action server

Prerequisites

• pyModbus >= 3.9.2

Setup Guide

Navigate into your ROS 2 workspace and copy this repo to your source folder

cd src && git clone https://github.com/ABC-iRobotics/onrobot-ros2.git && cd ..

Build the package (and installing python prerequisites)

colcon build --packages-select onrobot_rg_msgs onrobot_rg_description onrobot_rg_control

Usage

After installation the controller server and the controller can be run separately.

ros2 run onrobot_rg_control OnRobotControllerServer

Or by using the included example launch file.

ros2 launch onrobot_rg_control bringup.launch.py

Use the CLI controller by running in a new terminal:

ros2 run onrobot_rg_control OnRobotController --ros-args -p /onrobot/gripper:=<your gripper type>

Parameters

Using parameters require using DeclareLaunchArgument and LaunchConfiguration in launch files, command line arguments, or ROS parameters.

Command line argument:

<name>:=<value>

ROS parameter:

--ros-args -p /onrobot/<name1>:=<value1> -p /onrobot/<name2>:=<value2> ...

General

Using launch arguments and ros-args parameter the controller server can be customized:

Name	Argument	Usage	Values	Default
Gripper	gripper	Sets the used gripper type.	rg2, rg6	rg6
Control	control	Sets gripper control method.	modbus, sim (WIP), isaac	modbus
Offset	offset	Defines fingertip offset on one side	0 - 80	5

Modbus TCP/IP

For Modbus TCP/IP control the available parameters:

Name	Argument	Usage	Values	Default
IP	ip	Sets Compute Box IP.	0.0.0.0 - 255.255.255.255	192.168.1.1
Port	port	Sets Compute Box Modbus port.	0 - 65535	502
Changer Address	changer_addr	Defines controlled device	63 - 67	65

Isaac Sim

For Isaac Sim control the available parameters:

Name	Argument	Usage	Values	Default
Isaac joint states	isaac_joint_states	Sets joint state topic	/*	/isaac_joint_states
Isaac joint commands	isaac_joint_commands	Sets joint commands topic	/*	/isaac_joint_commands

Width / Height / Joint value cross calculation

Using the OnRobotRGControllerServer a query can be requested on /onrobot/pose. Using the GripperPose srv message setting either width, height or joint angle the service rensponds with the completed state information. This helps to identify the height offset in a set width between the fingertips.

Troubleshooting

In case of any issues, check the official resources:

• OnRobot RG2
• OnRobot RG6
• OnRobot Modbus Manual Chapter 6.2 Page 51.
• ROS2 Joint Control: Extension Python Scripting

Author

Makány András - Graduate student at Obuda University

License

This software is released under the MIT License, see LICENSE.