Hi! help please. Im trying to create a car tracking and monitoring system, along with RFID and GSM so you could access the car by RFID, SMS or key. I want to interface this with my central lock. I don't know how to connect my arduino to the central lock which is a linear actuator. help please. this is our thesis project.
Have you got any details of the actuator?- you could always get a second hand one from a breaker's yard and experiment.
But, I think you're on the wrong track if you think you should hook an Arduino direct to the actuator. Clicking a car's remote doesn't, surely, activate the door lock (edit: I mean in the sense that it doesn't talk direct to the lock): I surmise it talks to the system in the broader sense which (for example) deactivates the alarm, deactivates the immobiliser, switches on the interior light, peeps the horn etc etc. So I'd say, you need to talk to the car's system, not the lock.
Thesis in what?- if in some electronics / mechatronics / automation discipline you should be able to figure this out for yourself, by experimenting and engineering a solution.
Example door lock actuator. You'd need either a motor driver or a dual throw relay.
Hi! I've been busy... To get back on that, I only bought the actuator 12Volts. I didn't buy the security system that could be connected to it. We're building our own car security system. The actuator could work even without the car alarms that can be bought separately. There is a 2 wire there wherein you could connect a switch. When these 2 wires touched, usually white and brown, it locks and unlocks the door.
My problem is, I want to unlock/lock the door via SMS. That is instead of connecting a simple switch, I want my arduino to act as the switch
Forget the sms part for now: for starters you need to figure out how to get the Arduino hooked up to the actuator and its power supply, and use a button on an Arduino pin to emulate the arrival of the SMS.
Are you sure it's a simple matter of touching two wires together? Where does the actuator power come into the picture? Let's see the circuit you propose.....
Ok I've been looking at a few pix on the interwebz and I see that in a locking kit there is usually one actuator with more wires, including the brown and white and lots more wires which are the power and whatever. So presumably as you say, the brown and white need touching together to lock/unlock. I assume the electronics in the lock itself takes care of knowing if the lock is currently locked or unlocked so knows it must unlock or lock?
In that case I'd go for a relay where the Arduino controls the switching of the relay and the other side of the relay joins your brown and white together. Make sure you get a relay that won't draw too much current on the 5V Arduino. Have a Google for relay modules suitable for the Arduino. But remember that you'll need to have some shield or other for the SMS side of things and that will need power too.
thank you so much. I think i can do this one