The robot was designed as a test platform for an autonomous navigation system for factory / warehouse floors. It uses a single point LIDAR sensor on a servo to detect it's surroundings and 4 NEMA-17 stepper motors as drive, all controlled by the Raspberry Pi. It is powered by a large powerbank (for 5V power) and a 4s (14.4V-16.8V) lithium ion cell from an old drill to power the steppers.
It was mostly 3D printed (the base was sign-board (aluminuim-polycarbonate composite), and had rubber (from an old inner tube) added to the wheels for grip. It could be controlled by a third party playstation controller as well, and was really fun to drive around (small drift whoop):
The wheels were extremely over engineered for the task at hand...
A GUI was displayed on the 7" touchscreen to allow the user to add coordinates to a queue, either directly, or from a list of pre-saved positions.
It used a modifed version of the A* search algorithm to find the quickest path to the
goal coordinates, all of which was shown on the screen:
The final result was quite slow on account of the single point LIDAR having to scan with a servo (a 360 degree LIDAR would be better) but
it worked as a proof of concept, and I am happy with the results:
(Timelapse)
For a more detailed dive into the design, development and testing process, see Autonomous-Navigation-Robot/Navigation robot project (11000 words).pdf