Blink-192

Blink-192 is an experimental Rapsberry Pi robot that uses ROS to move and stream video.

Heavily based on the Teleop-bot example from Programming Robots with ROS O'Reilly Media

History

I named this robot Blink-192 because it has a lot of bright lights, and its local ip address starts with 192.

Originally, this robot used OpenCV to track and pick up all the small things around the office, but later I modified it to learn ROS. The opencv branch still has the original implementation (https://github.com/TheoKanning/Blink-192/tree/opencv).

Hardware

Blink-192 is made with the following hardware:

• Raspberry Pi 3
• Waveshare AlphaBot - I bought this kit without a Pi Included
• Raspberry Pi Camera 2
• 7.4V LiPo Battery - I bought this one

Software

• Raspberry Pi Ubuntu image - Ubiquity Robotics
• Pi Camera Node - Ubiquity Robotics

Note that this particular Ubuntu image isn't required, but it comes with ROS pre-installed and creates a wifi access point automatically.

ROS Package Structure

Nodes

• keyboard_driver: Reads keystrokes and publishes them to the keys topic
• keys_to_twist: Converts key messages into Twist commands and publishes them to the cmd_vel topic
• motors: Subscribes to cmd_vel and controls motors
• raspicam_node: Publishes video stream to /raspicam_node/image

Topics

• /keys: String containing latest keystroke
• /cmd_vel: Twist containing desired linear and angular velocity
• /raspicam_node/image: sensor_msgs/Image from Raspberry Pi Camera

Rviz

• config.rviz: Configures rviz to show /raspicam_node/image full-screen

Launch Files

• desktop.launch: Runs keyboard_driver node and rviz
• robot.launch: Runs keys_to_twist, motors, and raspicam_node
• run-local.launch: Runs everything

Resources

• http://shop.oreilly.com/product/0636920024736.do
• https://learn.ubiquityrobotics.com/
• https://www.youtube.com/watch?v=9Ht5RZpzPqw