rrt-global-planner

A Rapidly Exploring Random Trees (RRT) global path planner plugin for ROS.

Demo

Install Dependencies and Build

cd ~/catkin_ws/src
git clone https://github.com/mech0ctopus/rrt-global-planner.git
cd .. && rosdep install --from-paths src --ignore-src -r -y
catkin_make
source devel/setup.bash

Usage

Within the move_base node in your launch file, set the base_global_planner parameter to global_planner/RRTGlobalPlanner and load the required parameters.

<param name="base_global_planner" value="global_planner/RRTGlobalPlanner"/>
<rosparam file="$(find rrt-global-planner)/params/rrt_global_planner.yaml" command="load" />

After launching the system, when you set a move_base/goal using RViz's 2D Nav Goal or with an action client, the RRTGlobalPlanner will be called. The global path will be published as a topic for visualization. Optionally, a visualization of the full RRT constructed for path planning will be published.

RRTGlobalPlanner's output can be visualized in RViz. To see the global path, add a Path display and subscribe to ~/move_base/RRTGlobalPlanner/plan. To see the full tree (viz_tree must be true), add a Marker display and subscribe to ~/move_base/RRTGlobalPlanner/tree.

Examples

An example launch file for using RRTGlobalPlanner with the TurtleBot3 Simulation is located in rrt-global-planner/launch.

An example RViz config file for using RRTGlobalPlanner with the TurtleBot3 Simulation is located in rrt-global-planner/config.

Troubleshooting

If you find that the RRT global planner continues to produce plans even after a solution has been found, try setting the /move_base/planner_frequency to 0. Zero is normally what the default value is (see planner_frequency on the move_base Wiki), but that's not what the value is in the turtlebot examples. If you're running the turtlebot examples, you can change the parameter in turtlebot3_navigation/param/move_base_params.yaml.

If you see that the RRT planner repeatedly fails to find a solution, you may want to play around with the parameters in the rrt_global_planner.yaml.

ROS API

Published Topics

~/move_base/RRTGlobalPlanner/plan (nav_msgs/Path)

• The global path constructed by the planner. Used for visualization purposes.

~/move_base/RRTGlobalPlanner/tree (visualization_msgs/Marker)

• Visualization of full tree built during planning process.

Subscribed Topics

None.

Parameters

~/move_base/RRTGlobalPlanner/goal_tol (double, default: 0.05)

• Cartesian goal tolerance to be achieved by the global planner.

~/move_base/RRTGlobalPlanner/K_in (int, default: 4000)

• Maximum number of iterations to attempt to find a plan.

~/move_base/RRTGlobalPlanner/d (double, default: 0.2)

• Distance to extend tree per iteration.

~/move_base/RRTGlobalPlanner/viz_tree (bool, default: false)

• Whether to publish full tree on ~/move_base/RRTGlobalPlanner/tree topic for visualization purposes after planning success.

Services

None.