Arduino H-Bridge

Christopher Vaughan

So this is interesting, The H-Bridge not only reverses the direction of the motor, but you can pulse width modulate the Arduino and the motor has wonderful torque characteristics. I think that if I included a rotary encoder on the system I could achieve a high torque bi-directional 360 degree servo.

Robert Rennie

Radioshack had the Arduino motor boards on clearance last month, i grabbed 4 for $5 each!

Jan Mulders

You can actually build pretty good H-bridges yourself using the L293D, which is a really simple H bridge driver IC from Texas Instruements that is easy to drive from a microcontroller. You just turn one pin on to make the motor turn, and turn another one on to flip the direction.

Datasheet for IC: http://www.ti.com/lit/ds/symlink/l293d.pdf

You can pick up prebuilt Arduino motor drive shields off of Ebay for about $5 each!

http://www.ebay.com/itm/like/181210688809?lpid=82

They're really easy to program for and can handle up to about an amp at anything up to 36V.

If you get a cheap rotary encoder, you can build a pretty reasonable servo / PID control system yourself - but at a certain point it becomes cheaper and more sensible to just use an open-loop (no feedback/sensors) system like a stepper motor, or just bite the bullet and buy a $20 servo from Hobby King that's stronger than you are!

Christopher Vaughan

Thanks for the info, Yes i have messed with H-bridges before from adafruit. With the arduino and a darlington pair you can build an ac servo or even 12 v DC with great torque and low heating.