JumpingRobot_ROCO507

[TOC]

Introduction

The aim of this project is to build a robot with four jumping legs (which can fold) and four mecanum wheels, operated by a human via the Robot Operating System (ROS).

The system is distributed across:

• Raspberry Pi - which main task is to steer the robot's motors.

• Laptop with Linux operating system - enables human's interaction.

Features

The robot can:

• jump,
• fold its legs,
• drive in multiple directions.

The robot's behavior can be controlled by a human operating the "robot.py" node on the laptop.

Installation

Laptop with Linux:

1. Install ROS kinetic - follow steps from: http://wiki.ros.org/kinetic/Installation/Ubuntu

2. Create a catkin workspace - follow steps from:

   1. http://wiki.ros.org/catkin/Tutorials/create_a_workspace
   2. http://wiki.ros.org/catkin/Tutorials/CreatingPackage <instead of calling package "beginner_tutorials" call it "my_dynamixel">

3. Upload files to my_dynamixel package:

   1. upload the file "robot.py" to: ~/catkin_ws/src/my_dynamixel/

4. Build packages in catkin workspace

   1. Go to catkin workspace directory

      $ cd ~/catkin_ws/

   2. Build packages

      $ catkin_make

5. Configure .bashrc file

   1. Open .bashrc file

      $ gedit .bashrc

   2. Add at the bottom of the file following lines:

      export ROS_MASTER_URI=http://localhost:11311/
      export ROS_HOSTNAME=<the laptop's IP>
      export ROS_IP=<the laptop's IP>
      

   3. Source .bashrc file

      $ source .bashrc

Raspberry Pi:

1. Follow steps 1 and 2 from the laptop's instruction <instead of calling package "my_dynamixel" call it "my_dynamixel_tutorial">

2. Install Dynamixel Controllers driver

   $ sudo apt-get install ros-<distro>-dynamixel-controllers

3. Upload files to my_dynamixel_tutorial package:

   1. upload content of the "launch" folder to: ~/catkin_ws/src/my_dynamixel_tutorial/launch/
   2. upload content of the "src" folder to: ~/catkin_ws/src/my_dynamixel_tutorial/

4. Build packages in catkin workspace

   1. Go to catkin workspace directory

      $ cd ~/catkin_ws/

   2. Build packages

      $ catkin_make

5. Configure .bashrc file

   1. Open .bashrc file

      $ gedit .bashrc

   2. Add at the bottom of the file following lines:

      export ROS_MASTER_URI=http://the laptop's IP:11311/
      export ROS_HOSTNAME=<the Raspberry's IP>
      export ROS_IP=<the Raspberry's IP>
      

   3. Source .bashrc file

      $ source .bashrc

Running the system

In order to run the system, following steps are to be executed:

1. Run roscore in a terminal on the Linux laptop

   $ roscore

2. Connect the Raspberry Pi to a power

3. Connect to the Raspberry Pi from the second terminal on the laptop and run ROS nodes on the former

   $ ssh pi@<Raspberry_IP>

   $ roslaunch my_dynamixel_tutorial controller_manager.launch

4. Connect to the Raspberry Pi from the third terminal on the laptop and run ROS nodes on the former

   $ ssh pi@<Raspberry_IP>

   $ roslaunch my_dynamixel_tutorial start_pan_controller.launch

   $ roslaunch my_dynamixel_tutorial start_tilt_controller.launch

5. To enable human-control over the robot, run the following node in the fourth terminal on the laptop

   $ rosrun my_dynamixel robot.py

Human-control commands

Keyboard commands (to be pressed in the robot.py node window):

• W - full speed forward
• S - full speed backwards
• T - stop
• A - full speed left
• D - full speed right
• Q - full speed diagonal forward left
• E - full speed diagonal forward right
• Z - full speed diagonal backward left
• C - full speed diagonal backward right
• X - rotate at a full speed anti-clockwise
• V - rotate at a full speed clockwise
• Y - increase current speed by 7% of its maximum value
• H - reduce current speed by 7% of its maximum value
• O - setting the robot's leg to 0 position
• K - setting the robot's legs to the first starting position
• N - setting the robot's legs to the second starting position
• J - changing the robot's legs position by -0.05 (rad)
• L - changing the robot's legs position by +0.05 (rad)
• M - jumping (from the first starting position)
• O - jumping (from the second starting position)
• 0 - rotating legs up
• 1 - rotating legs down by 0.1 (rad)
• 2 - rotating legs up by 0.1 (rad)
• 3 - rotating legs down
• 5 - preparing legs to down-folding (when initial position is ~0)
• 5 - preparing legs to down-folding (when initial position is ~5.2)

Links to videos

Evaluation of the robot's driving behavior:

1. Early stages - https://youtu.be/BNNEmNGqUxc
2. Final stage - https://youtu.be/ybAbjyJAmC4

Evaluation of the robot's jumping behavior:

1. Just one leg - https://youtu.be/G1J8bCmxgGU
2. Early stages with all four legs - https://youtu.be/6cJKMZFHYcE
3. Four legs after some improvements - https://youtu.be/etr4STEtW9g
4. Final stage - https://youtu.be/HQ1hYwN6pAw

Height of a jump experiment - https://youtu.be/KC6PH26aIuQ

Legs folding - https://youtu.be/vKZoalooXHU

The robot's behavior animation - https://youtu.be/MrXAhyIWOSs

Final demonstration of all behaviors - https://youtu.be/TGW2EMyFp7g

Authors

Michal Bogoryja-Zakrzewski

Tengxiao He

Haiwei Xu