Thread: Do motion sensors work?

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How well do the motion sensor hacks work, I mean does there have to be a certain amount of light for it to "see" movement? The props I have that are supposed to have motion sensors on them never work. I usually end up having to have a small penlight shining on them from across the walkway so that when the beam is broken they will trigger.

anyone, anyone, Beuller?

Motion sensors are funny things, some are infra-red meaning they sense the heat from your body or any heat source and then they react by triggering your prop. Others are photo-sensitive and react to a light source in the area or more specifically, the interruption of a light source thus causing a trigger.

I am using an infra red trigger on some of my props. I purchased them at places like home depot and Wal-Mart. Basically i am using detectors that were made for one purpose and adapted for my haunt so instead of emitting a loud squeal or turning on a light, they are now triggers.
They may not work properly every single time but, if set up and adjusted properly, they will function basically as intended for your haunt evening.
Check out my profile and the one youtube video of my pop up coffin and you can clearly see my infra-red trigger.......good luck.

I position all my props that have motion sensors so that I have a light of some form pointing at them and then the ToTs have to walk thru that beam to set them off. For example, I have a flood light pointed at my donna of the dead. The light is on one side of the sidewalk, Donna is on the other, so as the Tots come by, nothing happens until that beam is broken

I use a variety of PIR motion sensors and they normally work very well for me in the light or in the dark. I don't have any hacked PIR sensors but i've used the ones from Haunt Master on his controllers, Cowlacious for his audio boards and other PIR devices from electronics suppliers.

I would say that they all trigger properly around 99% of the time.

I build 4 new motions sensors this year with this module:

http://www.gadgettown.com/pyroelectr....html?ref=base

Good tips but to the OP, you may be mistaking a photosensor for a PIR (passive infra-red) sensor.

The sensor you speak of that required you to add light is likely a photo-diode/photoresistor.

A PIR sensor required no light to work, the sensor detects infra-red radiated from people and other heat sources and can work in perfect darkness.

So just how does this magical box work?

I understand the IR part but what is the output & how is it used?

Connected to a relay that in turn controls what you are hooking it to?

I connect the output to a transistor (I believe the base pin) and connect whatever to that i.e led's and If using AC I connect the transistor to a relay.

Originally Posted by jpbaily1

So just how does this magical box work?

I understand the IR part but what is the output & how is it used?

Connected to a relay that in turn controls what you are hooking it to?

Most small DC PIR sensors operate on regulated 5VDC and have an output voltage around 3 - 3.5VDC. The exceptions are the large security light sensors that have an AC output.
The output voltage would be sent to a resistor (~1K ohm) and then to the base pin of a transistor, like a 2N2222 or a Darlington transistor. The other two pins (emitter and collector) of the transistor can be used as a simple switch to trigger your prop. For example, if you attach the wires that go to a "Try Me" button on a prop to those pins, the prop will fire when the PIR goes high.
Some caveats - many PIRs will pulse when they see a heat source. You may get more than one output pulse and if your prop is expecting to get a single pulse, it may re-trigger immediately. The other thing is that PIRs don't have timers built into them. They will send an output signal every time they see heat. To prevent this you need some kind of timer/controller to interrupt the signal until the prop is finished running and to provide an off-time delay so it doesn't get re-triggered right away.

That's what I've found to work, Scatterbrains.