Closed-Chain Affordance Planning Framework - ROS2 Interface

Build Instructions

This repository contains robot-agnostic ROS2 packages used to interface the Closed-chain Affordance planner with a robot. Follow these steps:

1. Install the Closed-chain Affordance Cpp libraries by following instructions from this repository:
   Cpp library installation instructions

2. Clone the packages from this branch into your ROS2 workspace's src folder and build and source them:

   cd ~/<ros_workspace_name>/src
   

   git clone [email protected]:UTNuclearRoboticsPublic/closed_chain_affordance_ros.git
   

   cd ~/<ros_workspace_name>
   

   colcon build --packages-select affordance_util_ros moveit_plan_and_viz cc_affordance_planner_ros
   

   source install/setup.bash
   

3. If using an AprilTag to detect affordance, also build and source the following packages:

   colcon build --packages-select apriltag_msgs apriltag_ros
   

   source install/setup.bash
   

Notable Dependencies

1. The moveit_plan_and_viz package utilizes some MoveIt tools, albeit only for visualization purposes in Rviz. To utilize this functionality, ensure moveit is installed along with the moveit_visual_tools package.
2. For AprilTag usage, install the ROS apriltag package with 'sudo apt install ros-<ROS_DISTRO>-apriltag`.

Run Instructions

The entry point for this planner is a launch file in a package named as cca_<robot> that contains robot-related information for closed-chain affordance planning. The framework is implemented for the following robots, and the links direct you to the repositories containing those packages and instructions on how to run the planner for each robot.

• Boston Dynamics Spot robot

Instructions to Implement the Framework on a New Robot

Creating and Building the cca_<robot> Package

Implementing this framework on a new robot is straightforward. All you need to do is create and build the cca_<robot> package that contains robot-related information for closed-chain affordance planning. To streamline this package creation, a script is available. Navigate to the closed_chain_affordance_ros directory and run the package-creator script.

cd ~/<ros_workspace_name>/src/closed_chain_affordance_ros

./cca_robot_package_creator.sh

The package will contain two files in its config folder: cca_<robot>_description.yaml and cca_<robot>_ros_setup.yaml, which will have empty fields with instructions to fill out. Fill them out. Next, to execute an affordance with the robot, provide affordance information in the cca_<robot>_node.cpp file located in the src folder of the package. Once this is done, build and source the package:

cd ~/<ros_workspace_name>

colcon build --packages-select cca_<robot>

source install/setup.bash

Running the Planner

1. Before running this framework, the following three things need to happen. Since there are numerous ways to accomplish this, depending on your system, we do not provide specific instructions here.

   • A follow_joint_trajectory action server is running on the robot to receive joint trajectory commands.
   • robot_description has been loaded onto the parameter server.
   • robot_state_publisher is running to publish TF data to RViz.

2. Run the service server to visualize the planned trajectory in Rviz with the following command:

   ros2 run moveit_plan_and_viz moveit_plan_and_viz_node
   

3. Run the planner, replacing <robot> with the robot name used to create the cca_<robot> package:

   ros2 launch cca_<robot> cca_<robot>.launch.py
   

Author

Janak Panthi aka Crasun Jans