Demo (ROS2)：

Demo of Force-position Hybrid Control Planning Arm_Force_Position_Control_Demo

1. Project introduction

This project is designed to realize the force-position hybrid control planning (available for the Cartesian motion similar to MoveL, but not for joint motion such as MoveJ) based on RM65 and RM75 robotic arms and ROS packages. The program will start the force-position hybrid control, execute the Cartesian motion, and stop the force-position hybrid control successively. Its purpose is to enable ROS developers to quickly master and flexibly use the robotic arm.

2. Code structure

├── CMakeLists.txt                    <-CMake build file
├── launch                            <-Launch folder
│   └── force_position_control_demo.launch   <-Launch file
├── LICENSE                           <-Version description
├── package.xml                       <-Dependency folder
├── README.md                         <-Readme
└── src                               <-C++ source code folder
    └── api_force_position_control_demo.cpp  <-Source code file

3. Project download

Download the project file locally via the following project link: ros2_rm_robot

4. Environment configuration

Item	Description
Operating system	Ubuntu22.04
ROS version	humble
Dependency	ROS2-humble package of the robotic arm

Configuration procedures

1. Prepare the virtual machine or other devices equipped with the Ubuntu22.04 operating system.

2. Install the ROS2 environment humble, or refer to the installation instructions in the ROS2-humble package for details.

3. ROS2-humble package installation

   Create a new workspace and src folder

   mkdir -p ~/ros2_ws/src

   Copy the ROS2 file to the src folder

   cp -r ros2_rm_robot ~/ros2_ws/src

   Enter the workspace

   cd ~/ros2_ws

   Build the rm_ros_interfaces package

   colcon build --packages-select rm_ros_interfaces

   Declare environment variables

   source ./install/setup.bash

   Build all packages

   colcon build

   Declare environment variables again

   ource ./install/setup.bash

5. User guide

• Usage of command lines:

  Launch the following rm_driver package of the robotic arm in one terminal:

  ros2 launch rm_driver rm_<arm_type>_driver.launch.py

  The <arm_type> is optional for 65, 63, eco65, 75, gen72, and others according to the actual device used. Launch the following force_position_control package of the robotic arm in another terminal:

  ros2 launch force_position_control force_position_control_demo.launch.py

  If it is not RM65 or RM75, the robotic arm may not reach the point, which is a normal phenomenon.

• Return information:

  The following prompts will appear when the program runs successfully.

  [rm_force_position_control-1] [INFO] [1722914114.076652595] [Force_Position_Control_sub_node]: *******Movej_p succeeded      //Prompt for the MoveJ_P succeeded
  [rm_force_position_control-1] 
  [rm_force_position_control-1] [INFO] [1722914114.248853737] [Force_Position_Control_sub_node]: *******Set Force Postion succeeded  //Prompt for successful setting of starting the force-position hybrid control
  [rm_force_position_control-1] 
  [rm_force_position_control-1] [INFO] [1722914116.432832020] [Force_Position_Control_sub_node]: *******MoveL succeeded       //Prompt for the MoveL succeeded
  [rm_force_position_control-1] 
  [rm_force_position_control-1] [INFO] [1722914116.548136946] [Force_Position_Control_sub_node]: *******Stop Force Postion succeeded  //Prompt for successful setting of stopping the force-position hybrid control
  [rm_force_position_control-1] 
  [rm_force_position_control-1] [INFO] [1722914116.647943527] [Force_Position_Control_pub_node]: *******All step run over      //Prompt for all commands completed

6. Key code description

The following are the main functions of the api_force_position_control_demo.cpp:

• Initialization

  Initialize the relevant publication and subscription information

  Subscriber for MoveJ_P command

  rclcpp::Subscription<std_msgs::msg::Bool>::SharedPtr movej_p_subscription_;

  Subscriber for MoveL command

  rclcpp::Subscription<std_msgs::msg::Bool>::SharedPtr movel_subscription_;

  Subscriber for starting the force-position hybrid control command

  rclcpp::Subscription<std_msgs::msg::Bool>::SharedPtr set_force_postion_subscription_;

  Subscriber for stopping the force-position hybrid control command

  rclcpp::Subscription<std_msgs::msg::Bool>::SharedPtr stop_force_postion_subscription_;

  Publisher for MoveJ_P command

  rclcpp::Publisher<rm_ros_interfaces::msg::Movejp>::SharedPtr movej_p_publisher_;

  Publisher for MoveL command

  rclcpp::Publisher<rm_ros_interfaces::msg::Movel>::SharedPtr movel_publisher_;

  Publisher for starting the force-position hybrid control command

  rclcpp::Publisher<rm_ros_interfaces::msg::Setforceposition>::SharedPtr set_force_postion_publisher_;

  Publisher for stopping the force-position hybrid control command

  rclcpp::Publisher<std_msgs::msg::Bool>::SharedPtr stop_force_postion_publisher_;

• Callback function

  After receiving the subscribed execution state of the robotic arm, execute the message callback function

  MoveJ_P result callback function

  void MoveJPDemo_Callback(const std_msgs::msg::Bool::SharedPtr msg);

  Result callback function of starting the force-position hybrid control

  void SetForcePostionDemo_Callback(const std_msgs::msg::Bool::SharedPtr msg);

  MoveL result callback function

  void MoveLDemo_Callback(const std_msgs::msg::Bool::SharedPtr msg);

  Result callback function of stopping the force-position hybrid control

  void StopForcePostionDemo_Callback(const std_msgs::msg::Bool::SharedPtr msg);

• Publish the MoveJ_P command

  Publish the MoveJ_P command to move the robotic arm to a target pose.

  this->movej_p_publisher_->publish(moveJ_P_TargetPose);

• Publish the starting force-position hybrid control command

  Publish the command to enable the force-position hybrid control of the robotic arm.

  this->set_force_postion_publisher_->publish(forceposition_data);

• Publish the MoveL command

  Publish the MoveL command to move the robotic arm to a target pose.

  this->movel_publisher_->publish(moveL_TargetPose);

• Publish the stopping force-position hybrid control command

  Publish the stopping force-position hybrid control command.

  this->stop_force_postion_publisher_->publish(stop_force_postion_data);