big dc motors interfacing

hi all,

im considering the make controller for an educational project im working on.

it needs more inputs/outputs than my arduino could afford.

what i basically need, is a way to interface two accu-drill motors (18V) since im making a robotic platform (probably acrylic + some aluminium rails) which needs to hold the make controller, small laptop and peripheral electronics (sensors, motor bridge and the motors themself).

i have worked previously with l293 on small motors, but that chip drives only up to 1A, and i believe i need more for the motors i intend to use.

now, since i have an extremely limited budget for this, i cant use specialized motor controllers like the ones used for robot fights. i've seen some other post where FETs are recommended for this kind of thing. does anyone have a schematic which will work with the motors i need?

thanks!

I'm also working on something similar, I have a N-channel FET which is controlling another circuit, I need to know how to switch this FET on from the Make Controller, I think this is what you need to do also?

I've tried but I cant figure out which way to wire up the FET?