help making a robot please

I need some hlp making a device that will help a group of handicapped kids to go fishing. Here is what I need help making. I need a
12 volt motor that will run off of a deep cycle battery, I need to attach to the motor a spool that will have some line attached to it. The spool must turn several times then free wheel back then pull etc... It will be sued to raise and lower the fishing tackle. I want to be able to adjust how many times the spool turns as well as the speed it turns. It must be able to pull at least a two pound weight up off the floor. It also needs to be very quiet, I could mount the motor inside a box if needed.
Any help would be appreciated.
Thanks Doug
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Sounds like you want a car powerwindow motor or wiper motors. Low RPMs (you want the gearbox). You would need to add some kind of encoder to it to control speed and position. A geared stepper motor would be a little better, since you can directly control its speed and number of steps. Also, you might want to look at magnetic clutches (to release the motor from the spool crank.) The motors at least can be found at surplus electronics sites:
http://www.goldmine-elec.com/ (a bunch of stuff) http://www.allelectronics.com/ (look in motors, Geared DC motors)
The best site: http://www.herbach.com (has electromagnetic clutches)
A heavy duty R/C servo might also work, but you will still need some kind of electromagnetic clutch to allow the "freewheeling" or a ratcheting assembly (like in a bicycle cone.) Hopefully someone else here will be willing to do the calculations for required torque for you as I did not do well in physics (I know it has something to potential energy ie... U = mgh, then angular torque....) Ahhh....here we go... http://howstuffworks.lycoszone.com/fpte6.htm /
Good luck, Scott

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I have about 100 orders from varius organizations that work with kids and adults, if we can get this made. I a m a photographer by trade and was asked to look into the possibility of have these made, this is a paying job so please pass the word.
Scott McDonnell wrote:

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