Hey all,
Just to preface this post, I'm a newbie at electronics projects, so forgive me if this is an overly simple project. ops:

What I want is a pair of (stepper?) motors that have only 4 available positions on them (3, 6, 9, and 12 o'clock) for intermittent use (i.e. 99% of the time the system will be stationary, I will just turn the dial to adjust the position of the motor). I want to control both motors from a single 4-position switch, what I'm picturing in my head are the printer input selector boxes you used to see with A,B,C, and D positions. The setup needs to run off of 12VDC (for a mobile application). The motors don't need to be very strong, the torque requirements are low. Shoot, I don't know what other details you'll need... so I'll put this up and follow up with any questions as they come.

TIA!
Aaron

 

Hi Aaron,
Can you tell us what you are trying to turn , it might give us some ideas / help with a solution.

 

Hi Lindy,

Thats ok, simple projects get more attention!!
How far away are the two motors, and are they together?

This dial that you turn, ...
is that to make the motors face different ways ?

Those 'input selectors'
all that come to mind for me are the dip switches,
thats those tiny little ones to set the settings.

(they are not made to be used very often in their
life, the settings arent expected to change often!)

If you mean those ones, you would have to get stouter
versions.

Please describe this in more detail.
Start with what you want as an end result.

Cheers, John

 

The easest way i can think of is to use a UCN5804 stepper motor driver IC for each motor. Use a 555 timer to generate the pulses and a counter IC such as 7490 to count off the number of pulses needed for each position.

You can also do this by using a Pic microcontroller to control the 5804 which would simplify the layout somewhat.

Heres a link that explains it in more detail.

http://www.imagesco.com/articles/picstepper/06.html

__________________
Two roads diverged into a woods...i took the one less travelled by. R. Frost.

 

Wow, thanks all for the quick responses! I really appreciate your help. Here's some more detail to the project.

I'm a bit of car buff and I have adjustable shocks/struts on my ride. To adjust the shocks, you take a tiny screwdriver and turn a dial on the top of the shock tower. To be more specific, you have to push the dial in about 1/4" and then turn, so the motors will have to be set on small solenoids. I think it would be super trick to be able to adjust them from inside the car. So that should answer the question of how far apart the little motors are, and no, the motors don't move. Also, that's why I only need 1 dial for 2 motors, since the front-right and front-left shocks will always be set to the same firmness settings. (I will run identical setups for the front and rear, but I wanted to simplify the question, so I'm actually going to use 2 dials to run 4 motors).

As for my reference to the "printer input selector"... well I hesitated about using that since they don't really use them anymore, but this is what I had in mind (except with 4 possible settings). Obviously, since this will be somewhere in my car (probably the glove box) I'll want it to be smaller.


I'll post a couple pictures of the shock tower adjustment in a few minutes...

 

The small black section (with the slot) in the center is what I'm trying to turn. You are free to turn it either way (i.e. you are not confined to clockwise or counter-clockwise movement.

Attached Images

shock_tower.jpg (11.0 KB, 745 views)

 

btt

 

Another option that might be simpler is to just have one button for each motor. Each time you push the button, it rotates the motor 90degrees. Would that simplify things?

 

Hi,

how would you make the mechanism for
pressing the end down,
and turning the stub ?
And letting the end back up again i suppose.

The circuit would come afterwards,
in many ways the circuit is the easy part.

Regards, John

 

Is there such a thing as a combination stepper motor and linear solenoid? If so, then all we need is a circuit that, when a button is pushed, extends the shaft, rotates 90°, then retreats. Is that possible?

 

Well nothing ready-made comes to mind,
i think such a unit would have to be specially made.

 

This page lists something called a "Combination Linear/Rotation Drive Assembly..." but it looks like it won't work. There must be something like this available with an external shaft...

 

Can you get in contact with the manufacturer of the damper mechanism?
It would make your task simpler if the need to push the screw before turning could be removed.

 

The owners manual specifically states that turning the adjustment screw w/o pushing in will break the valve.