Current Amplifier for a HIGH amp 12v motor.

I am working on my senior project for my mechatronics engineering degrees and i need to control four 12 volt motors with a labview/NI-Elvis board environment. The problem, which many of you will know from trying to run motors off of LavVIEW, is that it does not supply enough current to run the motors. So all i need is a current amplifier, the problem is that the motors pull 67.9A at full power and 133A at stall. All specs for the motors can be found at

https://www.robotmarketplace.com/products/images/VEX-217-2000.pdf

any feedback on what i should use to get the desired current so i can control the motors would be greatly appreciated.

You need 4 pieces of Pulse-Width-Modulation (PWM) DC motor controller circuits and a huge 12V/250A power supply. :roll:
Controller example:
**broken link removed**

Mmm - some fairly hefty 12V motors!

With those sort of current ratings, PWM (or some other switching strategy) will be your only realistic option for controlling/driving the motors. One of the mainstream (Australian) electronics magazines - Silicon Chip - published a number of designs which might provide some inspiration. I believe the only significant difference between their 20/30/40 Amp output stages were the paralleled number of MOSFETs, so you could probably scale this concept to your required power levels (while also paying attention to the quality of the MOSFET gate drive, which will tend to deteriorate as you parallel the FETs and their associated gate capacitances.)

Silicon Chip Online - 12V-24V High-Current DC Motor Speed Controller, Pt.1
Silicon Chip Online - High-Power Reversible DC Motor Speed Controller

Reversing direction would be most easily accommodated with a relay, switching the motor when it's at zero speed.

For a suitable power supply, lead acid batteries in parallel with a (much lower output current... = cheap) charger will be hard to beat from an economic and performance perspective.
Beware the mechanical and electrical power levels... and have fun!