[drwolfe]

It seems that electronics and circuitry in general has gone by the way of the dinosaurs. I'm seeking a simple motor control circuit design that acts like a garage opener. First pulse opens a predetermined amount of revolutions and time rotations or count revolutions... Then Stop. Next pulse will trigger reverse direction and time rotation or count revolutions. We have a surplus store that carries many 12 volt motors, worm, timer and other that could potentially be used in many application. Any one a electronics buff than can offer some advice?

[drwolfe]

I am hoping to find somebody with a background in electronic circuit design. The reasoning for this is that I am seeking a circuit that works much like a garage door opener. What I mean by this is that by one click a circuit can be activated in one direction and on the next click the direction will be reversed by the same pre-numbered determined rotations and or user defined rotations.

You would also be most flexible if multiple voltages such as 6 V, 12 V, 24 V and 120 V AC can be used by a high and low side circuit.

Please let me know if there is anybody who might be available to tackle the challenge.


Thanks

DR Wolfe

[rajenkins]

Hi,
I design stuff for a living.

There are many possible ways of doing what you ask, the big questions are what you will actually be moving - eg. speed, distance, weight or mass etc.

How accurate does the positioning need to be? Simple limit switches will give moderate accuracy and keep the overall complexity to a minimum, or using such as an optical encoder can give extreme accuracy.

Assuming limit-switch accuracy levels are OK, I'd think something like a CMOS Bistable IC, with a debounce on the clock input from the operating switch.

One output would go to a transistor operating (via a limit switch) a single pole changeover relay at one side of the motor, and the other output to a similar circuit switching the other side of the motor.

Each relay has the common contact to the motor, the normally closed contact to 0V via a low value resistor, and the normally open to the positive of the motor supply.

If one or the other relay is operated, the motor will run in one direction or the other. When they both release, the motor is shorted via the two resistors, stopping it quickly. Hitting a limit switch drops out the relay for that direction.

You could also use current sensing on the resistors and another bistable to create a safety stop circuit, so both outputs are gated off if the motor is stalled, until a new command resets it.

[drwolfe]

Thanks for getting back to me. The application have chosen to start with, is being able to actuate the vanes of a blind on all four major sides of my house.

I have installed timer motors that are reversible and currently I'm using two channels from a secu16 ocelot, one could trigger the power source and energized the motor and the other to use a relay that is trigger to reverse or forward direction.

What I would really like to be able to do is to use four or six channels from one ocelot via an secu16 that would act much like a garage door opener. One pulse would begin the motor rotating in the open direction, counting number of turns and the following pulse would reverse the motor direction counting of number turns and stopping. Waiting for the next signal.

Thank you kindly

DR Wolfe

[mikewhull]

http://www.smarthome.com/3142/Motori...troller/p.aspx

have you seen this. sounds like what you want already made.
mike

[rajenkins]

OK, the simplest way I can think of to do that is add a multi-turn potentiometer to the motor (gearbox) output. As long as you don't need more than ten or fifteen turns end-to-end you should be able to find a standard part.

You then need two multi-turn preset resistors (the screwdriver adjustable type) which will set the end limits.

Use two sections of a comparator IC, eg. LM339, to compare the output of the pot with each of the preset values. The outputs of the comparators will switch when the motor reaches one end or the other.

You can incorporate than into the two relay circuit I described above, but using the comparators rather than physical limit switches to drop the relays out when the motor gets to the end points.

[drwolfe]

Taken this topic on again. To finally complete the hal setup to star trek levels.

Is it possible to get a schematic with a list of components. I will be doing blinds 6V with timer motors. Power lift for av components using 12v power-door and or win-shield motor and 120V worm-gear power drawers. The surplus store has tons of different motors but the issue is one good design that the voltage, rotation can be regulated to suit the motor and application, as per need basis. I hate buying components only to blow them up because of factors a green horn wouldn't be aware of.

Thanks
DRWolfe

[bob in canmore]

I finally went for Lutron blinds and their controller. Works v. well. Will use Cinemar to adjust height from a touchpad (trying to get iPad going...) as well as using HAL for schedules adn rules based on house temp. The Lutron controllers work well with adjustable limit switches forfully open/closed.

[drwolfe]

Thanks Bob; its not really about just controlling blinds, its about custom creations. Power furniture

As an example I have an dedicated closet with all my av equipment contained in a custom cabinet. The custom cabinet is on wheels with tracks that allows the cabinet to be pulled out to facilitate component wires, power connections etc. The door is beefed up and is lockable from the inside by way of power automotive power door locks. Out of sight and very clean install. I open the split door and pull the cabinet out some so I can see the components and allow ir from the remotes to reach the components.

I have a hidden switch that throws a 12 volt power door locks. Total cost from the surplus store cost $10 for the power supply, two power door solenoids and switch (new).

When I'm done with the av equipment or going out. I push the cabinet in, close the doors and throw the switch to lock the closet. My goal is to automate this process automatically.

Its very easy to wire up manual switches to power up the drill and forward/reverse direction to existing wiring.The cost for a drill, threaded rod, mounting hardware including switches is about $40. Spin the rod the cabinet extends/retracts. A set of gears slows the spin and increase torque cost $10-20. We now have a platform. Use four rods attached by gears/chains similar in principle to a portable plainer height adjustment. and instant power lift to lift the flat screen up out of a cabinet. These devices are commercially available at hundreds or even thousands. Building it your self may be a pain but all the basic principles can be adapted. I'm building one and the top of the island will raise to expose the toaster, coffeemaker, microwave etc. all on one shelf. I have built this stuff before. When I'm done, turn a hand crank and it pops up like a camper trailer and you can still put stuff on the top of the island while cooking. So there we go, hide the stuff when not in use.
Cost effective solutions for everyone, motor control is the key.
DRWolfe

[bob in canmore]

Man, I gotta see this!!! Can you post a video?

bob