Circuit help: momentary bi-directional DC motor control

[supak111]

Hey everyone, been trying to make a simple circuit to control a DC motor bi-directionally in a specific way.

I have a 12VDC motor that I need to run in one direction for 2 seconds (roughly 1-3 sec is fine) every time a key in a car is turn ON (so when the circuit HAS power run for 2 seconds clock-wise direction and cut power)

and once the car is turn OFF (circuit loses 12V power) I need the circuit to run the DC motor in the counter clock-wise direction for 2 seconds and cut power. Repeat next time key is turn to ON

What would be the easiest, cheapest way to make a circuit like this, I may need many bunch of them in the future, this may not be a one of build.

I was thinking about using a cheap china Arduino and an h-bridge, but for some reason I feel there might be a simpler way with maybe a few micro relays and some circuit I haven't yet though of.

Any thoughts?

 

[Nanren888]

What sort of output power is required?
As in, do you have a concept of the motor size that is appropriate to the role?
.
Available patched to work as arduino, the attiny range would likely do it as you suggest, if programming is for you.
For simple, short delays, 2 seconds, that do not have to be very accurate, something simple based on 555 timers, or 556 dual timers, might also do it, with the right relay or two, or that H_bridge.
Which direction is your preference? What's priority?
price? electronics? programming?

 

[bertus]

Hello,

In the old days we had an automatic car antenna:
https://www.google.com/search?as_st...&as_sitesearch=&safe=images&as_filetype=&tbs=
Those where put out when the radio was turned on and pulled in when the radio was turned off.

Bertus

 

[supak111]

Motor might drew upto 1 amp at 12v at for those few seconds while it ON.

I can program a $2 Arduino with an $2 h-bridge (this may end up being the only way), but I was wondering if there was a simpler way. There are some prebuilt 555 modules but all I've seen are single relay and not DPDT

Yea I though about the auto antennas but those have micro shut off switches inside which for my project just wont work unfortunately

 

[AnalogKid]

The thing about running a motor both directions on a timer is that the motor will not return to the exact same position each time. Over time, the rest position might creep far enough out of place to be a problem. For whatever the motor is moving, are limit switches a possibility?

ak

 

[supak111]

My device has things in the way so it will be stopped at both ends after about 1 second in each direction. This is why I just want the power off after 2 sec to prevent it from overheating the motor

 

[AnalogKid]

The way the question is written in post #1, it sounds like you want the motor to run for 2 seconds after all circuit power is removed. That can be done, it you add in a large capacitor that can store enough charge to run the motor for 2 seconds. Your problem is much more simple if the circuit and motor have power available constantly, and some kind of input signal tells it when to act.

ak