Motor question

[Warlock]

My neighbor and I were talking and want to use some type of motor control for next year (ya I know planning already) but we are not sure which type of controller would work any ideas ???Yes for computer control via vixen if possible...If anyone has used this idea or knows how to do it please let me know.
Thanks for the help..
Joe..

[NogginBoink]

By 'control' do you mean simply off/on, or do you need speed control as well?

Also, what type of motor is it?

I hate to answer a question with more questions, but the ultimate answer really does depend on these things.

[Warlock]

It's a servo motor.On / off would be a great start with possible speed control later on.Or if you know how to do it via vixen I'd sure like to know what board to use that will work...

[DynamoBen]

I'm doing motor control for Halloween this year. I'm using a windshield wiper motor to control a skeleton marionette via DMX. I built the motor controller myself. All it is is a PWM output (from my microcontroller) going to a Mosfet (radio shack part). There is a 1K resistor between the mosfet gate and my microcontroller. I then wired the motor to the mosfet and powered the system with a converted ATX power supply...it worked great.

This is where I got the idea, but I did add some things. I added a flyback diode and capacitor between the terminals at the motor to reduce noise on the buss.
http://www.neufeld.newton.ks.us/electronics/?p=133

I have full speed control, but only in one direction. If you wanted to go multiple directions and speeds an H-bridge is the way to go. A quick google search should get you what you need.

If however you want an off the shelf solution I would suggest something from Parallax.
http://www.parallax.com/html_pages/products/motorcontrol/motor_control.asp

[NogginBoink]

For a DC motor, yes, you can use PWM.

By 'servo motor,' do you mean a servo like for radio controlled airplanes and such? Those servos require a PWM input that's proportional to the shaft rotation. You'd need a controller such as a PIC chip to accept data from Vixen and translate the information into an appropriate signal for the servo.

[Warlock]

Alright so you could for example use Firegods board and have it work either way ??

[rovingmind]

I might be out of line for chiming in like this, but how about stepper motors. You could set aside 2 or 4 channels (depending on the stepper) and pulse them right from Vixen. You would have to be Very Careful about your timing so that you didnt overlap pulse cycles, but you automatically have speed control by spacing out your pulses, along with reversing. It would work for lighter displays like wavers or halloween flying bats/ghosts without having to program anything. You would have to match the steppers to the 5volt feed, and maybe add a current amplifier. Not the ideal solution, just something i've been thinking about since playing with Vixen to learn its capabilities..

I havn't tried it yet, I'm just getting started and dont have a control board yet, I'm gathering the parts for a Grinch controller and playing with vixen. A single 4 channel ssr output should suffice for the steppers i have on my junk shelf.

Has anybody else tried this?