The Raspberry Pi Rugby Ball Explorer

6 RPi Zero 2 Ws mounted on a rugby ball shaped device for exploring shafts. Contains setup notes and scripts to run the code.

To get the RPi ready and to run the code, please follow these instructions.

The RPi Zero 2W are not the best at handling large video images and proved to be quite limited as far as performance goes. Details can be found in the Camera Test Results.

TLDR; Maximum reliable video size: 1920x1280 at 30fps. Maximum still frame rate at 4608x2592 = 1fps, 2304x1296 = 2fps, 1536x864 = 3fps. Writes to micro SD card are main blockage.

Hardware and drivers

• Flow sensor - PWM3091
  • https://github.com/RealRobotics/optical_flow_ros
  • https://github.com/pimoroni/pmw3901-python
  • https://pypi.org/project/spidev/
  • https://pypi.org/project/RPi.GPIO/
• IMU - ICM20948
  • https://github.com/pimoroni/icm20948-python
  • https://github.com/RealRobotics/icm20948-ros2
  • https://github.com/CCNYRoboticsLab/imu_tools
• Camera - ArduCam 12MP IMX708
  • libcamera drivers and tools
  • https://github.com/anholt/libepoxy
  • https://github.com/raspberrypi/libpisp
  • https://github.com/raspberrypi/libcamera
  • https://github.com/raspberrypi/rpicam-apps
  • https://github.com/pipebots/camera_ros

The wiring schedule is here.

Acknowledgments

© 2023, University of Leeds.

The author, A. Blight, has asserted his moral rights.