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Sensor and Quick Release for Monster Trap Christmas Gift Answered

I'm building a Christmas present for my 2 year old nephew... The goal is to build a monster trap for his room.
My current plan calls for a large 2-3 ft. net, framed with a lightweight material, this would be attached to the ceiling of his bedroom by dad.

In the apparatus that attached the net to the ceiling there is some form of 'quick release' mechanism that is triggered by some form of sensor hidden in a pillow, platform, cardboard box... a big stuffed banana -something that resembles monster bait.

The physical parts of simple enough but I'm wondering what options I have for the sensor and quick release... I'm pretty handy with radio gear and fly quadcoptors so I'm pretty sure I can rassle up something.. Any ideas?

Parts for Monster Trap:

- one lg net, preferrably framed
- radio controlled quick release
- light sensor w/ radio transmitter
- pillow or something to mount the light sensor in
- screws to ceiling mount the net


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8 years ago

You can go with a simple photoresistor if there is a light source in the room. (A photoresistor changes its resistance with light.) You could probably just have a the photoresistor in series with a properly sized resistor and a 9V battery under the bait so it's covered and it's resistance is high. When it's uncoverd, the resistance drops and voltage in between the photoresistor and the resistor rises. There's your signal. This is how many nightlights work but the opposite way.

You could honestly just take one of those nightlights and have the power that would normally keep a light on in the dark power a latch holding the net.

One thing to consider. This child is two years old, and a net may prove to be a choking hazard. Make sure that NEVER has the possibility of happening.