dc42:
I found the datasheet for that actuator at Linear Actuators & Motion Control Products - Progressive Automations. It takes from 2A at no load to 9A at full load and max speed. If the load is expected to be light then MC33926-based H-bridges such as http://www.pololu.com/catalog/product/1213 should be suitable.The homing sensor is likely to be an optical pickup that provides a signal once per revolution of the screw so that revolutions can be counted. Once you know its details, you can easily simulate that with an Arduino.
Thanks for your help, I appreciate it. The homing function I was originally referring to is done at the machine start up. The VMC re-homes each motor at start up, if a motor takes too long to respond then a motor error is reported and that motor is shut down until the error is resolved. You may have described another potential scenario with the feedback that we will need to simulate.