Occassionaly, we don't pull the car in far enough. The door comes down and scratches the back of the car.
I would like to display a red led whenever there is an obstruction (car) breaking the beam.
I want to construct a photo sensor solution?
I see a broad array of emitters and sensors.
But, I need a recommendation to integrate with a controller and transformer.
I am capable of fabricating mounting brackets, soldering, etc..
Is there a kit or source of simple designs like this? I tried the reference library and didn't fine one.
Detecting a light emitter from across your garage door can be a bit of a hassle, mostly because you have to compete with the giant burning emitter in the sky. Correctly biasing your detector might actually be impossible, given the ultra-wide range of ambient light conditions you'll be fighting. Most new garage door openers that come with a safety beam system use lenses and filters to block out all but the light they're interested in. It's not impossible, just a hassle.
Another possibility is doing it farther inside the garage. You could detect when a beam is broken by the front bumper and turn a light on. Alternatively, you could use an ultrasonic range sensor on the back wall of the garage to detect the distance to your front bumper. When the distance crosses a set threshold, it turns a light on.
...or, the easiest option:
Hahaha, this is now my current running favorite for the "Best TechXchange Answer Ever" award.
What is that, a tennis ball on the end of a golf ball retriever extendable pole?
I don't expect sunlight will be a problem that far into your garage, and it sounds like you want to show your kids some cool stuff. Below is a very simple, but inexpensive circuit that should do the trick provided you work out the mounting and alignment. The Stop LED is pretty small, but could be a starting point. The circuit could be tweaked to use something like this, but it requires a different power supply and more current than the phototransistor can handle (would require a 12V supply, different resistors and an additional transistor). If you have any questions, let me know.
Since I'm learning to do electronic as hobby.
I would like to build one to stop two SUV in garage. Would it be possible to put in the rear bumper to give clearance between of garage door and bumpers? Bright LED red stop light in front for both SUV. Does this required adding power supply for front LED and rear sensor? Can you draw schematic or circuit diagram?
It would be a lot easier to simply have it indicate when the front bumper is in the correct position, if that's right, the rear bumper should be in the garage.
Hi Dave. You should definitely take a look at www.mbed.org which is a site devoted to the use of microcontrollers and their applications. You'll find designs and circuits for your purpose there, using ultrasonic transducers used in rangefinding applications. I'm sure you'll find the site hugely interesting. The forums will get you an answer to all your electronics questions too.
Message was edited by: GregoireLeGros
Here's another distinctively non-tech solution: Mount a wide-angle mirror (can obtain at any auto parts store or the big W) on the back wall of your garage at the height of the center of your vehicle's rear window. The driver can see the mirror when pulling in either way, and in the mirror you can see the remaining distance between bumper and wall. Could also align it with the side of the vehicle, rather than dead-center, to allow seeing brake/backup lights or headlight in the mirror. Could alternately use a regular (non-wide-angle) mirror and angle it such that once the vehicle appears in the mirror, the vehicle is at the correct distance from the wall (so that you don't have to identify both the vehicle and the wall in the mirror, which could be challenging if the mirror is small).
I like lasers.
What about using something like the following: VLM-650-03-LPT-ND and mount it on the ceiling of your garage. Park your car exactly where you want it, then point the laser so it appears on your dashboard right in front of the steering wheel. I'm sure Digi-Key has a power supply or some combination of components that would allow you to either plug into a nearby wall outlet or make it self-contained.
Just don't look up.
How about the problem with operating temperature range?
I think that most garages anywhere north of the Mason-Dixon line get colder than that. ;-)
I guess I figured most folks have heated garages like I do. Might have to re-think which laser to use...
Perish the thought! I already heat a 5000 sq/ft house, I'm not heating that big garage too! Truthfully, I don't know anyone around here that heats their garage. Also, in the hot summer, I'll bet a lot of garages in the South get a lot hotter than 30C.
I know it's a bit late, but I just found a project that an EE built so that he can open and close his garage door with Siri: