ROS 2

This tutorial assumes you have either pre-installed ROS 2 or launched the included VS Code development container. For more details, please see .devcontainer/readme.md.

Note

Before proceeding, please install the Reach Robotics SDK. Instructions for installation can found in the Getting Started section.

Warning

BPL Protocol will be deprecated in 2025 and replaced with Reach System protocol. The ROS 2 packages provided in this SDK are for the convenience of the user and are not currently supported by the Reach Robotics team. If you need support with your ROS 2 integration, please speak to your Reach Robotics sales representative for a quote (all services are subject to availability).

Setup

First, source the ROS 2 underlay:

source /opt/ros/foxy/setup.bash

Note

It can be convenient to automatically source this script every time a new shell is launched.

echo "source /opt/ros/foxy/setup.bash" >> ~/.bashrc
source ~/.bashrc

Keep in mind, if you have more than one ROS distribution installed, ~/.bashrc must only source the setup.bash for the version you are currently using.

Build the ROS 2 packages:

cd ~/workspace
colcon build

Source the ROS 2 overlay packages:

source ~/workspace/install/local_setup.bash

At this point the Reach Robotics nodes have been built and are ready to use.

Note

If you are using a ROS 2 distribution other than Foxy, you’ll need to modify the source command accordingly. I.e. `source /opt/ros/humble/setup.bash`

Packages

The ROS 2 folder is split into several packages. Each package is briefly described below.

bpl_passthrough

The BPL passthrough is the core package that facilitates communication to Reach Robotics products. This passthrough converts ROS 2 messages into Serial or UDP packets that can be read by the connected product. Each node in the passthrough uses bpl_msgs/Packet for messaging. The packet construct is defined as:

uint8 device_id
uint8 packet_id
uint8[] data

where device_id is the device identifier, packet_id is the packet identifier, and data is a list of 8 bit integers representing the data to be sent. To launch the passthrough, run:

SerialUDP

ros2 run bpl_passthrough serial_passthrough --ros-args -p serial_port:=/dev/ttyUSB0

where,

• serial_port (string) - Serial Port to connect to the arm (Defaults to “/dev/ttyUSB0”)

• baudrate (int) - Baudrate port of the serial connection. (Defaults to 115200)

For both passthrough nodes, the published topic and the subscribed topic, respectively, are:

• /rx (bpl_msgs/Packet) - Received Packets from the manipulator

• /tx (bpl_msgs/Packet) - Packets that will be sent to the manipulator

Examples

This example demonstrates how to request read joint positions from joints on a manipulator. To launch this example, run the launch file.

SerialUDP

ros2 launch bpl_passthrough serial_passthrough_example.launch.py serial_port:="/dev/ttyUSB0"

The script communicates to the passthrough node via the /tx and /rx topics. It publishes request packets to the /tx topic at a set frequency. It subscribes the to /rx topic and listens for position packets.

Note

This script has been tested to work at 400 Hz over a UDP Connection to the Base MCU.

bpl_bravo_description

BPL Bravo Description package contains the Universal Robot description File (URDF) files for the Bravo range of manipulators.

Supported Products:

• RB-7002 - Reach Bravo 7 (PRO)

• RB-5002 - Reach Bravo 5 (PRO)

Examples

Examples of viewing URDFs in RVIZ.

Viewing a Bravo 7 URDF:

ros2 launch bpl_bravo_description view_bravo_7.launch.py

Viewing a Bravo 5 URDF:

ros2 launch bpl_bravo_description view_bravo_5.launch.py

Viewing a Bravo 5 and Bravo 7 URDF:

ros2 launch bpl_bravo_description view_bravo_double.launch.py