Piper ROS2

The Piper ROS2 repository contains multiple packages for working with the Piper robot arm.

• piper_description package contains URDF Xacro and configuration files that describe the manipulator.
• piper_bringup package contains launch files for bringing up simulated environments of the manipulator.

Visualizing URDF

ros2 launch piper_description view_urdf.launch.xml

Simulating with Mock Hardware

ros2 launch piper_bringup piper.launch.xml mock_hardware:=true rviz:=true

Simulating with Gazebo

ros2 launch piper_bringup gazebo_piper.launch.py headless:=false rviz:=true

MoveIt Example Configuration

To try out the included MoveIt configuration you can use Mock Hardware or Gazebo.

If simulating with Mock Hardware no additional arguments are needed to start Moveit.

ros2 launch piper_moveit_config demo.launch.xml

If simulating with Gazebo:

ros2 launch piper_moveit_config demo.launch.xml sim_gazebo:=true

Testing Available ROS2 Controllers

You can send manual commands to the running controllers with the following examples:

• RQT Joint Trajectory Controller

(sudo apt install ros-$ROS_DISTRO-rqt-joint-trajectory-controller)

ros2 run rqt_joint_trajectory_controller rqt_joint_trajectory_controller

• To send commands to the joint_trajectory_controller's topic interface:

ros2 topic pub /joint_trajectory_controller/joint_trajectory trajectory_msgs/JointTrajectory "{
  joint_names: [joint_1, joint_2, joint_3, joint_4, joint_5, joint_6],
  points: [
    { positions: [0.0, 0.85, -0.75, 0.0, 0.5, 0.0], time_from_start: { sec: 2 } },
  ]
}" -1

• To send an action goal to the gripper_controller:

ros2 action send_goal /gripper_controller/gripper_cmd control_msgs/action/ParallelGripperCommand "{command: {name: [gripper_joint], position: [0.03]}}"

Git LFS

This repo uses git-lfs to store the mesh files in the piper_description package. You can install and activate with:

sudo apt install git-lfs
git lfs install

If you have cloned this package without git-lfs pre-installed you can run git lfs pull to pull down the assets.