Test follow-path with the qrb_ros_follow_path service - Qualcomm Dragonwing Documentation

The key features include:

Waypoint and virtual path management on the map.
Path following navigation to target waypoints.
Obstacle avoidance during path following.

Software structure

The following figure shows the software structure of the qrb_ros_follow_path service:

Layered stack on RBx with 2D lidar ROS, robot base, 2D lidar SLAM, follow path service, and follow path manager running on ROS2 Jazzy. — Software structure of qrb_ros_follow_path.

ROS nodes and modules used in the `qrb_ros_follow_path` service

The following table describes the ROS nodes and modules used in the qrb_ros_follow_path service.

Node name	Description
qrb_ros_follow_path	This ROS2 package implements the action/service clients and servers, publishers and subscribers for waypoints, virtual paths, follow path navigation, position and lidar data.
qrb_follow_path_manager	This is a C++ library that provides APIs for waypoints and virtual path management and path following navigation. • Manager: Library interface. • Virtual Path Manager: Manages waypoints and virtual paths and computes the follow-path. • Follow Path Planner: Sends linear speed and angular speed to Robot Base Controller, checks for obstacles on the follow path and supports dynamic obstacle avoidance. • Obstacle Detector: Uses laser scan and a grid map to detect dynamic obstacles. • PID Controller: Computes the speed and checks if the target pose is reached.
Robot Base and Robot Base Controller	This is a ROS2 package for autonomous mobile robot (AMR) base control.
2D lidar SLAM ROS and 2D lidar SLAM	Provides mapping and localization.
2D lidar ROS	Provides lidar data.

`qrb_ros_follow_path_service` APIs

The following table describes the qrb_ros_follow_path_service APIs.

Interface	Name	Type	Description
Subscriber	`developer_mode`	`std_msgs::msg::Int16`	Receives debugging information.
Subscriber	`robot_base_exception`	`qrb_ros_robot_base_msgs::msg::Exception`	Receives exception information.
Service server	`virtual_path`	`qrb_ros_navigation_msgs::srv::VirtualPath`	Manages waypoints or the virtual path.
Service server	`compute_follow_path`	`qrb_ros_navigation_msgs::srv::ComputeFollowPath`	Computes the follow-path, including the passing through waypoints.
Service server	`follow_path_sub_cmd`	`qrb_ros_amr_msgs::srv::SubCmd`	Cancel, pause or resume follow path.
Action server	`wfollowpath`	`qrb_ros_navigation_msgs::action::FollowPath`	Request a follow path navigation.

Prerequisites

You have set up the device, installed ROS2 Jazzy and the Qualcomm Intelligent Robotics (QIR) SDK on the device according to Install the QIR SDK.

Run out-of-the-box `qrb_ros_follow_path` service

Run the following commands on the device unless otherwise specified.

Install the qrb_ros_follow_path service packages

sudo apt install ros-jazzy-nav2-msgs
sudo apt install ros-jazzy-nav-2d-msgs
sudo apt install ros-jazzy-qrb-ros-amr-msgs
sudo apt install ros-jazzy-qrb-ros-navigation-msgs
sudo apt install ros-jazzy-qrb-follow-path-manager
sudo apt install ros-jazzy-qrb-ros-follow-path

Set up 2D lidar SLAM

Set up 2D lidar SLAM by completing the steps 1-6 in Run out-of-the-box 2D lidar SLAM. Ensure that the mapping is completed.

Set up the sample environment on the device

source /opt/ros/jazzy/setup.bash
source install/setup.bash
ros2 launch qrb_ros_follow_path qrb_ros_follow_path_bringup.launch.py

Test the follow-path service

You can implement a ROS node according to the qrb_ros_follow_path_service APIs table to complete the follow-path navigation.
You also can use these ROS commands to complete the follow-path navigation.

a. Install rqt-robot-steering on the host computer (Ubuntu 24.04).

sudo apt install ros-jazzy-rqt-robot-steering

b. Run rqt-robot-steering on the host computer.

ros2 run rqt_robot_steering rqt_robot_steering

c. Use rqt_robot_steering to move the robot base to an expected position.d. Install and set up rviz2 on the host computer (Ubuntu 24.04).

sudo apt install ros-jazzy-rviz2
ros2 run rviz2 rviz2

e. Get the pose from rviz and convert the pose to a 2D position (x,y,angle).f. Add a waypoint with the current position.For example, if the current position is (0.1, 0.3, 3.0), use the following command:

ros2 service call /virtual_path qrb_ros_navigation_msgs/srv/VirtualPath "{api_id: 2, waypoint: {x: 0.1, y: 0.3, z: 3.0}}"

Get the waypoint ID from the service response. For example, waypoint ID is 1.g. Use rqt_robot_steering to move the robot base to another position.h. Get the pose from rviz and convert the pose to a 2D position (x,y,angle).i. Add a waypoint with the current position.For example, if the current position is (0.3, 0.1, 3.0), use the following command:

ros2 service call /virtual_path qrb_ros_navigation_msgs/srv/VirtualPath "{api_id: 2, waypoint: {x: 0.3, y: 0.1, z: 3.0}}"

Get the waypoint id from service respond. For example, waypoint ID is 2.j. Set the virtual path between waypoint (id = 2) and waypoint (id = 1).

ros2 service call /virtual_path qrb_ros_navigation_msgs/srv/VirtualPath "{api_id: 6, waypoint_id: 1, adjacent_waypoints: [2]}"

k. Start a follow-path operation from waypoint (id = 2) to waypoint (id = 1).

ros2 action send_goal /wfollowpath qrb_ros_navigation_msgs/action/FollowPath "{goal: 1}"

Build from source and run the `follow-path` service

Build the follow-path service from source when you need to change the service code. The device steps install the dependencies, clone the source repositories, build the packages, and run the result.

Device steps

Install the dependencies

sudo apt install ros-jazzy-nav2-msgs
sudo apt install ros-jazzy-nav-2d-msgs

Download and build

source /opt/ros/jazzy/setup.bash
git clone https://github.com/qualcomm-qrb-ros/qrb_ros_follow_path_service.git
git clone https://github.com/qualcomm-qrb-ros/qrb_ros_interfaces.git
colcon build

Run and test the service

Run and test according to step 2 to step 4 of Run out-of-the-box qrb_ros_follow_path service.

​Software structure

​ROS nodes and modules used in the qrb_ros_follow_path service

​qrb_ros_follow_path_service APIs

​Prerequisites

​Run out-of-the-box qrb_ros_follow_path service

​Build from source and run the follow-path service

​Device steps

Software structure

ROS nodes and modules used in the `qrb_ros_follow_path` service

`qrb_ros_follow_path_service` APIs

Prerequisites

Run out-of-the-box `qrb_ros_follow_path` service

Build from source and run the `follow-path` service

Device steps