as well as the two sketches along the lines you suggested.
Hello, I am a software guy who is new to using stepper motors. Basically I have built a large moving bookcase door that rolls back and forth. I have connected it to steel cables and pulleys into the attic where I want to place a stepper motor and gearing to open and close the door. I had imagined using a chain drive attached to the steel cables. Size is not a problem as all of the mechanics are up in the attic.I am not sure where to start and do not expect you to all my work for me but could you at least point me in the right direction?Here is what the operational parameters are: Distance of travel: 40 inchesForce to roll Bookcase: 25 lbs (measured by pushing on a scale against the bookcase) Actually it was probably closer to 30 to get movement started and 18 while moving.
Expected time of Travel: about 3 seconds maybe more
Frequency of usage: No more than 45 times a dayWhy a stepper? This "Bookcase" will actually contain some fairly fragile artwork - sculptures etc. so i want to be able to accellerate and decelerate smoothly. I plan to use ultrasonic distance measurers to confirm the position as there is some slack in the cables and I would expect some stretch. Obviously exact positionoing is really only important at the beginning and end of the motion. I will also use infrared motion detectors to check for obstacles (either stationary or moving - think scurring dogs trying to beat the door).I can gear the motor as needed as there is no problem with space.