Arduino for Motorised Wheelchair

Hi,

that motor driver is not suitable for your application because it can only provide currents of up to 1A.

Hi Bobby,

You might want to check the specs on your motor before you look for a larger H-Bridge. The 24 Volts 3 Amp specification would only yield 72 Watts. If the motor in fact can deliver 320 Watts at 24 volts you may be looking at 13 to 14 Amps. As far as the dependability of the Arduino I have found it to be very reliable when properly used and engineered into the application. Some of the aftermarket inexpensive knockoffs may be a little questionable. Relays may not be the best way to go as they deliver all or nothing of the power that you need. Ideally the power to your motors should be control by technique called Pulse Width Modulation PWM which allows you to gradually increase and decrease power to the motor and thus eliminate high acceleration starts and stops.

John

This will not be a straightforward task for a mechanical engineer on your own.

It's power electronics with high currents that's going to be used by persons with a handicap. I think it's best to team up with someone from the electric engineering department.

Hii  bobbyppaul

here are answers of your questions...

1. How effectively can we use Arduino for Motorised Wheelchair ?

Ans: Arduino can easily control 4 DC Motors (I dont think Wheel Chair need more than 4 motors) using PWM very efficiently.. It also have Enough ADC input to connect Joy Stick(Simplest way to control wheel chair)

2. I heard from someone that Arduino is not reliable and it will burn off easily is it true ?

Ans: Not true at all... Arduino is just programmable small computer... Due to human error by means of wrong wiring / Wrong code can burn other hardware (i.e. motor driver) and wrong power supply or applying more than specified voltage (i.e. 5V for Arduino) to input pin of Arduino can damage arduino.. but this is true for all microcontroller in the world..

3. Can anyone help me developing a circuit which is reliable and consistent ?

Ans: Surely community members here(including me ) always happy to help you.. Also As you are faculty (me too ), I think your institute/university definitely have Electronics/Electrical department, so you can get get help from students or faculty of these department who frequently using arduino.

4: I did some experimentation with Arduino and Relays we had jerks in wheelchair as it was just helping to switch on and off and Relay was burning off frequently.

Ans: As relay directly run motor with max torque, jerks are obvious, to solve it you need to use PWM with motor driver to get throttle (speed here) of motor, have a look at answer of next question for more clarity.

5: I am trying to use motor Driver L293D to control the motors.

Ans: L293d will not work as it can be used up to 1 or 1.5 Amp current maximum per channel... Your specification needs lot more current (normally working 10-15 Amps and stall current of motor will be more than 20amps) So I suggest use H-bridge using IRF540 and IRF9540 MOSFETs which can easily handle 25 Amps, Its very low cost solution and using PWM channel arduino u can control speed of motor too.. (not just on-off which is case of relay)

6: Can I use 'map' function to link Joystick input and motor output. Is it the best way to do it ? Or is their any other alternatives.

Ans: yes its a best way to do, as joy stick output dynamic range is 0-1023 but PWM for motor output dynamic is 0-255, map function will serve mapping of this ranges to get max throughput on motor. There are other alternatives also to get user input but I dont think your use case needs it to be explore..

Hope this helps...

Ravi

Hi

Thank you very much for your reply. Now I have clarity on what should I do.

Thanks Once again.

This forum is amazing.

Bobby

Thank you very much for your advice. I will look for some one in electrical for help.

Thanks once again.

Thanks for the information.

Thank you very much. This gives me more clarity.

Hi Ravi,

I enjoyed reading your excellent reply to Bobby's question.

John

Thank you very much. I was reading the posts. Sorry for the late reply.