How to control a DC motor

[pverbrug]

So for my mechanical engineering class, we are building a rotating tool carousel much like the big ones that they have at Home Depot. We are using a 12 VDC motor from the Mile Marker Pe3500. we are designing so that the amps from the motor will not go above 100A. For the project we need to know exactly where the motor is rotation wise so we are using an absolute rotary encoder to feed that information back to a computer.

The motor controller needs to be able to vary the voltage to the motor from 0-12V (the maximum output voltage from the controller can be greater that 12V) and it would be nice if it could also send a negative voltage for bi-directional control. We also either need the controller to interface directly with a laptop, or need some way to make it be able to.

Now, I have been searching for a way to control the rotation on the motor. I have found many motor controllers, but none fit our needs exactly. If anybody has any suggestions it would be greatly appreciated.

[A_Person]

Assuming I found the correct product, this is a motor from an ATV winch and you are just sending it a control signal.  You can go through the data acquisition products at ni.com/daq and look for USB or PCMCIA devices to use with your laptop but all of them are only going to do -10 to +10V.  If you need the full 12V, you'll have to look at adding an op-amp to your circuit.

[Brian_Beal]

You must us a DC drive to do this.  You will not be able to drive this directly from a DAQ card.  Look at Minarik or Roboteq for DC motor controllers.  100 amps seems high.  You will only be drawing that kind of current with a large load.