Controlling Multiple DC motors

Hi all.

I'm trying to do a project where I'd need to control multiple DC motors (forwards and backwards) independently. In a perfect world I would be able to control about 100 individually, but for the prototype I think I'm going to shoot for between 7 and 11.

I looked into the Arduino Motor Shield, which was send to me as a kit and I have not yet been able to get it working. My question is: How many DC motor's should I be able to control with a single Duemilanove or MEGA board. Should it be a fairly simple circuit using multiple H-Bridges ? Can anyone point me to a good resource or tutorial. I've done the perquisite hour or so of googling, and I'm not formally trained as an electrical engineer, however I'm pretty quick to pick things up.

Any help would be greatly appreciated :slight_smile:


If all you need is on/off and direction control, not speed control (PWM), then you can use any of the techniques for expanding the number of output pins. I'd suggest either 74HC164 serial-in, parallel-out shift registers or the populat 74HC595 shift register. Once you have enough output pins, then you can connect them to H-bridge drivers such as the L298 or the L293.

You'll need to know the current consumption of your motors, and you'll need a larger external power supply.