Software Integration

Overview

The process of “Software Integration” was designed to integrate all subsystems, control and validate the robot’s behavior according to a selected user story. The behavior can be induced by defining conditions in subsystems.

Software integration uses behavior trees to create each behavior and make decisions about the robot’s behavior. The first draft of the project uses py_tree and py_tree_ros, Python implementations of behavior trees, to manage the behaviors of the robot. More information about py_tree can be found at https://py-trees.readthedocs.io/en/devel/.

The developed behavior tree’s structure is divided into three major parts: the root tree, behaviors classes, and subsystem nodes. The root tree was used to create the behavioral flow and call behaviors of the robot. The diagram below (Fig. a) shows the behavior flow of the robot’s first draft. Behaviors classes are used to start subsystem nodes with service and receive status feedback from subsystem nodes. The diagram below (Fig. b) will explain correlation of behavior class and subsystem node.

Fig. a shows the behavior flow

Fig. b explain correlation of behavior class and subsystem node

Installation

• Install py_tree

  sudo apt-get install ros-foxy-py-trees
  

• Install py_tree_ros

  sudo apt-get install ros-foxy-py-trees-ros
  

• Test simple behavior tree

  • Setup

    git clone https://github.com/MBSE-2022-1/Software-Team.git
    cd sample_ws/
    colcon build --symlink-install
    

  • Run node

    ros2 run sample_integration node.py
    

  • Run root node

    ros2 run sample_integration root_tree.py
    

  • Result

Example

scope of this example for a developed behavior tree is not decided in a failure case

• Setup workspace

  git clone https://github.com/MBSE-2022-1/Software-Team.git
  cd demo_ws/
  colcon build --symlink-install
  

• Setup hardware

  1. Camera

     ros2 launch realsense2_camera rs_launch.py \
             rgb_camera.profile:=640x480x30 \
             depth_module.profile:=640x480x30 \
             pointcloud.enable:=true
     

  2. Wheel odometry

     sudo chown $USERNAME /dev/ttyACM0
     ros2 run xicro_pkg xicro_node_sub_N_pub_ID_3_stm32.py
     ros2 run xicro_pkg nav_msg_publisher.py
     

• Run all subsystem node

  ros2 launch integrate_system launch_node.launch.py
  

• Run root node

  ros2 run integrate_system root.py
  

Note

You can see all Software Integration’s packages from this github : https://github.com/MBSE-2022-1/Software-Team.git

Subsystem Verification

Software integration testing is separated into four subtasks: start task, check color task, carry luggage task, and follow people task. Each subtask incorporates some behaviors such as

1. Start task : PointedGestureCmd -> SpeechStart -> PointedGestureCmd

2. check color task : ObjectDetect -> SpeechCheckBag

3. carry luggage task : ObjectDetect -> ManiGrab -> ManiRelease

4. follow people task : PeopleDetectBehavior -> SpeechFinish

This testing is intended to verify the infallible operation of subsystems as well as the correct operation of the root node. When testing, do not test the resource used between the working and quality of each subsystem.

Problem and future plan

• Current Issues

  • Use almost full resources when running all subsystems.

  • Sending the camera’s data from Intel NUC to Jetson Xavier throws lan cable effect to processing speed of working of subsystems that use the camera’s data.

• Future Plan

  • Manage node initialization and destruction; initialize nodes when they’re needed and destroy nodes when they’re finished.

  • Develop a behavior tree to decide behavior when there is a failure case.

  • Increase the behavior that corresponds to the hardware’s behavior.