I am Akhil and i am working on a small motion platform powered by a stepper motor. I have been following some of your forum replies to some people having problems with USB stepper Motor Card from OpenCockpits. Luckily I got the Nema high torque stepper motor running with the USB stepper motor card (using SIOC monitor) without any overheating. I tried testing it with the motion platform i created and the torque it provides is quite sufficient for my needs. But there is a small problem. I did not connect an optical sensor but instead used a potentiometer because i need position feedback for the motion platform. When i started sioc and tested it through sioc monitor, it just keeps turning and turning and never stop even after i close SIOC..!!..I know a guy called Jack had the same problem before but he had a script to test otherwise. I am new to SIOC scripts and I didnt get a script ready to test coz i do not know where i can find information on 'how to monitor the rotation of the motor with changing values in the potentiometer through a script'. Could you help me up with a mock up script which uses potentiometer values (0-255) to give position feedback to the motor.

And why do you think the motor is just turning and turning. Is it because of the absence of an optical sensor?? But because i am using a motion platform and not a chronograph as many people mentioned in their replies, i opted for the potentiometer. Please help.

Below is the diagram of the platform. The linear rail that is connecting the ballscrew is connected to 2 springs which are in turn connected to the diamond shaped plastic (which rotates 35 degrees left and right about the pivot point). The script should take IAS values from FSX and ask the motor to turn a specified number of turns so that it tightens and loosens the springs at different IAS.

Please help me out.