motorized tie rack

anyone know how to control a stepper motor to make a motorized tie rack? seen at the department store...36 ties...you punch in tie #21 and the motor moves to 21st position, and then you enter #10, and it moves to 10th position. would like to use android to control via bluetooth. :)

Denied, not allowed. Arduinos are for nerds not yuppies. ;)

Denied, not allowed. Arduinos are for nerds not yuppies.

if he tries doing it with the arduino it will absorb him into itself ;) ;)

“Which tie goes with this shirt?”

Everybody knows that the orange tie goes with the lime green shirt. ;D

Well, you could do what I did: cut back to two ties.

Then you could make the rack with a servo ;D

Unless you're custom-designing the rack so the spacing precisely syncs up with the step size of the motor, you probably want to use a geared stepper, so you have lots of steps per slot. Gearing also lets you use a smaller/weaker stepper.

You should also mark slot 0 with something like a flag to trigger an opto-interrupter, or a magnet to trigger a Hall effect sensor. That allows you to keep the CPU synchronized with the position of the rack.

And, with CPU control, if you discovered it takes, say, 10.1 steps per slot, you could add an extra step every 10 slots to correct the error.

While certainly not a cheaper option, you could just get married and let the wife pick out the tie. Just don't let her pick out tools for you at Home Depot, you will be disappointed. ;)

Lefty

haha...didn't know you nerds were so funny ;) More seriously the jokes on me since I'm a newbie and have seen the tutorial on steppers that was recommended...any further details that someone can provide on programming the arduino....not sure how to tell it to move to the next position given where it is. Ie it is in position 10, now move to position 15. Waiting for my stepper shield from adafruit and also using the bluetooth shield from sparkfun. the instructions from the web seem pretty clear on adding the bt shield. happy holidays to all. ;D

You could also set up a DIY trigger/interrupt mechanism, kinda like the Wheel of fortune, with the pegs and flapper,

Each tie position will have a metal peg, and a stationary mounted (conductive) flapper runs over them as the motor spins.

The Arduino would just keep track of which position it's currently at and calculate how to get to whichever position you request.

You would have to figure out how to do some serious debouncing in a system like that, and how to handle Power-cycles (where the arduino would lose its current tie position)

Debouncing shouldn't be too hard if you tweak your hardware then modify the button debouncing script, and to take care of powercycling you can write the current position into the Arduino's EEPROM on every move(although the EEPROM has a limited number of read/write cycles) as long as nobody forces the rack to rotate by means other than the motor.

Who keeps tracks of ties by number? Thats certainly a case of your inner nerd calling the kettle black;-) I think I would just let it spin until I saw the one I wanted.

A great opportunity for the random() command. Let the Arduino be your new fashion consultant!