I am trying to make a swerve drive wheelchair and I’m looking for help on the software side of things. A brief description of the project is that it uses 4 scooter hub motors independently powered and steered to create a platform that moves intuitively and smoothly based on input from a joystick.
Any robotics and software advice is much appreciated! If you are in the bay area and are interested in helping me build this thing, shoot me a message. It’s 2018! Swerve drive wheelchairs need to be a thing!
I stopped work on that design for various reason and have revisited the design a couple of times but
never had the interest to keep going. it worked well enough on joystick but autonomous with localization never worked to well
I used motors with feed back to act as servos through chains and sprockets but there was a lots of unnecessary steering movement
and it was slow. I have since seen large servos on aliexpress that would made steering easier link
I’m interested in trying to learn to write the software to run this thing. Does anyone have imput on where to start? Could you program this on a rasberry pi? Is python the language you would use?
The first version of omni_bot ran on a arduino mega with a joystick on the analog inputs the response time was OK. steering was just a PID controller using only the proportional, not very accurate. the drive velocity was mapped to PWM. Any errors in direction were easy to compensate with the joystick. Later versions ran ROS with a python interface on a RPI and 8 arduinos with full PID loops communicating over rs485 to a master arduino
If you are still out there, question to you… If you were going to build this today - Do you think these wheels would be a good way to go? If so what would you recommend as a controller? And what software would you use?
I don’t know if anyone is out there and still looking at this but I am interested in working on the steering and motor control software through simulation. Does anyone know what software I could use to simulate the steering software before any hardware is built?
This is a mockup I made a while ago showing the way the wheels need to steer in relation to the turn center. The wheels are just reacting to the turn center, always staying perpendicular to it. This is just a simple mockup and works by using simple constraints in inventor.
