Wheelchair based robot with autonomous & manual motor control

Hello, New here...also new to Arduino & robotics but learning a lot in the past few months.
I took Basic a loooong time ago and Fortran (old school hehe) in tech school several years ago.

I'm 'attempting' to make a robot from an Invacare M51 Pronto wheelchair that I got for a great price.
One thing I would like to do is with various sensors (ultrasonic, motion detection, Lidar(? $$...not sure hehe), or maybe kinect, is to have it move around and maybe follow autonomously and also detect and avoid obstacles.
The wheel chair has 2 DC motors with each one running at 24V and 350Watts (about 15A?)
I would also like to use a Transmitter (it's a new Spektrum DX5e, 5 channel trans.) to control the main motors/drive manually. The 5th channel is a toggle switch and I was wondering if I could use this toggle to go between auto and manual control with the Arduino. This would be just for the main motors/drive on the wheel chair, all sensors, etc... would continue functioning.


I attempted to control an old wheel chair myself a while back. Hooked up my Turnigy 9X receiver to the arduino and had the arduino replace the joystick on the wheelchairs control board. Whenever i moved the stick on the transmitter it would replicate what the analog joystick would have said. So what i was going for was a wireless chair to do my evil bidding... Unfortunately that route never worked out and i was too cheap to buy speed controllers for it, then i ran out of time to troubleshoot... But i would love to see someone succeed. You can indeed use that toggle switch to switch modes. Were you going to go with the receiver hooked up to arduino then arduino to speed controllers and sensors route of wiring?

Ahh, very nice :slight_smile:
Thanks for the reply.
I'm waiting to get the motor drivers in the mail. I was thinking the 2X25 Sabertooth/MegaMoto shields would be enough power to drive them.
I messed around a bit with the joystick module. This one has 4 coils on the pcb placed in the cardinal directions with a 5th one at the bottom of the joystick. Tried using a couple of servos to control it but it's super finicky when in the neutral position. If it's not dead on the joystick will not work. That and the oem speed controller (or at least what's programmed in) is slow and very sluggish.
I would have to buy/rent a programmer for that chair to change the settings :confused: Just going to go with one that uses the Arduino.
Not sure how I'll switch auto/manual, maybe switching the signals on & off. If in auto mode, I could switch the pwm from the Arduino programing to possibly another pwm/signal pin that the Spektrum receiver uses...? hmm not sure :slight_smile:

"Were you going to go with the receiver hooked up to arduino then arduino to speed controllers and sensors route of wiring?"
Yes, I believe so, or something similar.

I was thinking that the 5th channel toggle, hooked up to the Arduino can act like a 'switch' within the programing. When toggled to manual mode, it sends a signal on the pin where the 5th channel is wired to, sets all the outputs from the sensors, etc.. that drive the motors to low and high for the input pulses from the receiver?...


You could read that 5th channel with a digitalRead(), it should appear as HIGH on your reciever. I aprove of the sabertooth, great brand. Thats the way to go if you have the money. I thought about servos as well, dont think i will try it now. For all your sensors i would think that Kinect would be the cheapest for getting all the results you want, but the hardest to program. I would start with an ultrasonic or IR distance sensor and go from there.