Computer controlled cord-winding mechanism with physical limits

I would like to attach a cord-winding mechanism to a linux machine.

The object suspended from the cord will have a specific physical travel range. I'd like to be able to tell the mechanism 2 things: - raise object to upper limit - lower object to lower limit

I've drawn up an overview of what I want to do here: Mechanism Overview

I need some help working out the simplest way to build this system. When I say system I am talking about the entire system ie cord spool, motor, control unit, computer interface and software

I need help working out all the components that I would need.

Any thoughts?

Thanks

if the signal is sent, raise the device until it reaches the stop. then turn off the motor. if the signal is sent, lower the device until it reaches the stop. then turn off the motor.

add some safties so it does not run past the stops.

other than that, it should be a simple program.

mjurgens: I need some help working out the simplest way to build this system. When I say system I am talking about the entire system ie cord spool, motor, control unit, computer interface and software

You don't say what experience you have with mechanical or computer systems or programming.

If you are starting from scratch on all fronts this will be a major challenge.

You will need something to signal when the cord is down, and when it is up. The simplest is probably a couple of microswitches that are triggered by something attached to the cord. Then you can use a geared DC motor to wind out until the down switch is triggered or wind up until the up switch is triggered. You could organize the wiring so the switches directly cut power to the motor. Then you could have an Arduino control a couple of relays to turn the motor on or off.

How you connect the Arduino to your Linux PC is more complex. The cheapest would be a wired connection but Xbee wireless or WiFi might be more suitable. I have no experience of Xbee but I believe one unit can connect directly to a PC without needing a second Arduino. An Arduino Yun comes complete with WiFi. I have written a demo EzScrn which is intended to make it easy to use a Yun over a WiFi connection. But it might be a bit of a mouthful for a complete novice.

You may also be interested in planning and implementing a program.

And, if you are a novice, start by studying the examples that come with the Arduino IDE.

And full marks for a clear diagram.

...R