Mustang, thanks for your input on using the Arduino to control electric retracts, I decided to bite the bullet and purchased the Arduino uno and shield, as I mentioned before this is all new to me and I am trying to get get my head around the code,(" I'm retired now and certain things take longer to grasp"). I am hoping that most of your code will work for my system,albeit somewhat different to your own in that your servo's which have feedback wires I believe are going to pin 7 and 4 to use as a signals from your door servo's.
I am not using servo's for the doors, I have small actuators I made to operate the doors, which work in the same way as the retracts do, ie two wires to power the motors with no signal wire, these would have to operate in the same way as the actual retracts, two wire motor control with over-current trip at end of travels, I was planning to operate the three retracts on one motor output on the shield,
with door actuators on the second output of the shield, with some adjustment in the code for the value of the current sensing for three motors in each of the two outputs. however
The confusion to me is, how can I send signals in the code, and what pins to use to send these signals, in your code, I believe you indicate pins 7 and 4 for signals from servo's to do this function.
I'm not sure what pins I need to use, or how to modify your code to allow me to use my door actuators in place of the servo's you are using which have signal wires, I would appreciate any help you can offer which would help me to set up the Arduino to suit this application.
Specs. for the units I have are:-
The motors for retracts :- pololu 1091 HP 30/1- gear ratio - 350 rpm @ 6v 70Ma free run current @ 6v with a stall current @ 6v 1500Ma 2o oz-in @ 6v
The motors for doors :- pololu 1093 HP 30/1- gear ratio - 1000 rpm @ 6v 120Ma free run current @ 6v with a stall current @ 6v 1600Ma 9 oz-in @ 6v


I chose these motors on the basis of torque required and the speed required for actuation.
ie:- retract speed - distance of threaded nut travel = (25 mm) - divided by seconds to retract ( 6 ) - divided by thread pitch of 4mm rod (0.75) - x seconds per min. (60) = 333 rpm motor speed @ 6 volts

ie:- door speed - distance of threaded nut travel = (25 mm) - divided by seconds for doors (3 ) - divided by thread pitch 3mm rod (0.50) - x seconds per min. (60) = 999 rpm motor speed @ 6 volts
The above suited my needs, however the distance of travel and the seconds to retract can be changed to suit individual requirements.
Hope you can help.
Mike