Non-DIY Car Detection?

I would like to detect when our car arrives in the garage. The DIY ultrasonic sensor solutions are more work than I care to commit.


Induction loop wire in the floor, connected to an induction loop controller. That controller would provide relays configurable to 'pulse on detect', 'pulse on undetect', and 'presence' (permanently energised while the car is there). The relay output could then be connected to the Zigbee, Z Wave contact or input module of your choice.

They're easy to set up and you can get the parts from any automated gate supplier. I used to use these all the time for safety circuits on automated gates, barriers and rising kerbs.

You basically cut a 1" deep saw cut in a rectangle shape in the floor. The rectangle would be 1 metre front to back and as wide as you want it. As it has a field of 0.5m radius around the wire you ensure that the cut is 0.75m from the wall or any metallic structure. The circumference of the loop determines how many times you wrap the wire round in the cut:

  • up to 6 metres - 3 turns
  • 6 to 10 metres - 2 turns
  • 10 metres plus - 1 turn

The cut is then sealed over with whatever you like. We used to use polyurethane sealant but it's not too important.

That's awfully DIY for a non-DIY solution :smiley:. Though, I suppose, they're all DIY solutions if you think about it.


Does it have to be within your garage, as opposed to your car arriving just outside your garage?

@iharyadi has made a car arrival sensor that I have been using for several months that has worked very reliably for me.


Well yeah DIY is Do It Yourself. It is however a professional solution used for virtually every automated gate, barrier, bollard installed and is also used to detect cars waiting at traffic lights so it's fair to say it works.

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This isn't completely DIY but how about a simple old-fashion photoelectric sensor with a dry contact output and either a zooz relay or an ecolink contact sensor with dry contacts? the DIY part would really just be two short wires.

Would it be ok for any car(perhaps any object) detected open your garage?

If you need to specifically detect your car, you need more than just a simple ultrasonic sensor. I believe some people use it to detect whether a spot in the garage is occupied.

To open a garage, I personally not comfortable just to detect whether an object is present at a spot.

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