METR4202 Team 3 Project Guide

Description:

The project requires the team to design and implement a robotic arm for use within an airport to be used to pick up and deliver passengers luggage from a moving conveyor to specified drop zones. The design implemented by the students replicates the functionality of the required but at a smaller scale using blocks and aruco tags.

Github Link:

All code can be found on the team github: https://github.com/ShankssD/METR4202-T3

Team Members:

• Shanker Dorairajan - 44791151
• Tom Atkinson - 45319486
• Hokul Srikanthan - 45286113
• Abdul Wahab Mirza - 45556160
• Will Schwarer - 44818777

Hardware and Software Used:

Robot Operating Software (ROS): Used for the functionality of the robot, connecting the code to the physical design. Raspberry Pi: Used as the main system between the Ubuntu OS computer and the robot. Visual Studio Code (VSCode): Used for the programming on the Raspberry Pi for ease of use.

Package Structure:

• ax12a_interface: Stored location for dynamixel launch files.

• dynamixel_interface: Contains all files for the dynamixel. Obtained directly from the dynamixel github.

• project_description: Contains all files for running the project simulation in Gazebo.

• robot_vision: Contains files related to colour detection. Code for colour detection and calibration obtained from https://github.com/uqmvale6/metr4202_color.

• robot_kinematics: Contains the inverse kinematics, trajectory planning and all other motion and judgement based files within this package.

  • Nodes:
    • inverseKinematicsRotation.py
      • Subscriber:
        • /newEffPosition
      • Publishers:
        • /desired_joint_states
    • conveyorTrial.py
      • Subscriber:
        • /fiducial_transforms
      • Publishers:
        • /conveyor_rotation
    • blockTransformPub.py
      • Subscriber:
        • /fiducial_transforms -/conveyor_rotation
      • Publishers:
        • /availableBlockTransforms
    • dropper.py
      • Subscriber:
        • /set_height_state
      • Publishers:
        • /desired_joint_states

• sg90_gripper: Contains the files related to the SG90 Gripper inclusive of gripping and releasing the block.

  • Nodes:
    • gripper_actuate.py
      • Subscriber:
        • gripper_actuate
      • Publisher:
        • gripper_state

• ximea_ros_cam: Contains all files for the Ximea camera. Obtained directly from the Ximea github.

• st_machine: Combines all the code into one working state machine with all logic implemented.

  • Nodes:
    • stm_wait.py
      • Subscriber:
        • /availableBlockTransforms
      • Publisher:
        • /newEffPosition
        • /set_height_state
        • /gripper_actuate

Launching the Robot:

1. Run the terminal.
2. Using the computer's terminal, SSH to the Raspberry Pi using ssh metr4202@ip where the ip would be obtained using if config on the Raspberry Pi.
3. Enter into the catkin_ws workspace and use roslaunch robot_kinematics robot_start.launch.
4. Enter rosrun st_machine stm_wait.py in order to start the state machine.
5. Enter rqt_image_view in order to view the camera if desired.
6. All files should be launched and the robot should work.