When running a large haunted house, you want most of the special effects to be automated. But for this to be effective, you need to get the timing right. The best way to do this is to use sensors to detect where your guests are.

In this project, I am going to show you how to make a simple DIY pressure plate switch. This is just a pressure sensitive switch that is activated when someone steps on it. A sensor like this is really useful for effects that require someone to be in a specific location.  I also give several examples of ways that you can use it to activate special effects in a haunted house. 

Step 1: Materials

Here are the materials and tools that you will need to make your DIY pressure plate switch:

3 Large Sheets of Cardboard
Aluminum Foil
Several Feet of Insulated Wire 

Wire Strippers
A Sharp Knife
<p>so useful</p>
<p>will it work if it's smaller? (3 by 4 inches)</p>
<p>Could have used this for my digital doormat</p>
Great! :D<br><br>I'm going to make it to activate a mini water pump I just made, to put in my cats water fountain! :D<br><br>They like to drink water from the kitchen sink. But no more. :D<br><br>Thanks! Now I just need some other material... The cardboard would get wet and so on. ;)
<p>Is it possible to use the switch in a reverse manner that if not connected, activate something?</p>
That could definitely work. Just change the code to fit your application.
<p>Yay, i made the pressure plate and i connected it with a led. When you press it or step on it, the led goes on!</p>
<p>What kind of wires did you use? I'm having a hard time finding wires that'll fit snug into my breadboard</p>
I don't know exactly what kind of wires I used, but I stripped the ends of to fit into my breadboard...
Cool. Thanks for sharing.
<p>can I wire this into a breadboard then onto a an arduino? so I can support more than one pressure sensor one one arduino? or does i have to wire directly to the arduino?</p>
You can wire it together any way that you want. Just think of it as a large switch.
<p>Can you please explain exactly how to connect the wires to the battery pack and light bulb? thanks </p>
<p>Take a 12V battery or power adapter. Connect one wire to the coil of a relay and the other wire to the pressure plate. Then connect the other wire on the pressure plate to the other terminal to the coil on the relay. Now when the pressure plate is stepped on, the relay will activate. You should hear a clicking sound. </p><p>Then take an extension cord and cut it in half. Separate the wires for a few inches and strip the insulation off the ends. Connect the two wires from the male end of the power cord to the common terminals on the relay. Then connect the two wires from the female end to either the normally closed or normally open terminals on the relay depending on whether you want the light to turn on or off. Then just plug your light into the female end of the power cord.</p>
<p>after reading your post and reply to kayah334 i attempted a really rough drawing so i could wrap my mind around what connects to what. what do I do with the male end of the extension cord after the other end is connected to the relay?</p><p>as im understanding it I have 1 plate &gt; coil on relay, 2nd plate &gt; power supply &gt; coil on relay . then with the extension cord i have the female half and the male half. female half gets connected to the open or closed terminals on relay &gt; plug in whatever i want to have on/off per the plates. the male half i have connected to the common terminals &gt; then what? </p><p>If my &quot;schematic&quot; is correct i just have a male plug hanging in the wind lol</p>
<p>Here is a quick sketch to help illustrate how I hooked everything up.</p>
<p>I put one of these together last year. Normally, a string of jack-o-lanterns is on, but when you step on the switch the jack-o-laterns turn off and a ghost turns on. spooky, right? is there a way to extend the amount of time the ghost is illuminated after the switch is released? </p>
<p>There are time delay relays. Or you could make a time delay relay circuit with a capacitor and a could of transistors. You can search for examples online. Or you could use a relay latching circuit.</p>
<p>ok, I think I got it, thanks!</p>
<p>simple, cheap and functional. i love it. definitely one to bookmark for future projects.</p>
<p>I like it . It's so simple but also extremely awesome</p>
<p>Just from watching the youtube video my mind is flooded with all kinds of projects I wanna experiment with now! lol Its beautifully simplistic which makes me want to try it immediately! </p>
I most definitely was shorting 5V to ground. Sometimes I have to do stupid things and ask stupid questions to get things done the right way. Thanks for your help. Should be a cool little project.
So I have wired the switch up to the microcontroller. I wired 5V from the microcontroller to one end of the switch, and ground to the other, along with the pull up resistor. However, every time I close the switch my Arduino actually powers off.... Anyone else have this problem? Any help would be greatly appreciated.
Check how you have it wired up. If you are shorting the 5V to ground, you would overload the board.
Who said it had to be for halloween only?
Seems like with extended use the cardboard would start to sag together in the middle and be constantly touching together... How long before this happens?
It all depends on how hard you are on it. It could probably hold up to a night a 10-year-olds occasionally stepping on it. But if you want to use it for a longer time with larger adults, then you probably want to use the wood paneling and sheet metal that I mentioned in the last step.
You can omit the pullup resistor and use the internal pullup resistor by setting the input pin &quot;HIGH&quot;. Just use the digitalWrite &quot;digitalWrite(buttonPin,HIGH)&quot; instruction and set the input pin high in the setup list.
Very nice instructable! I have created several similar for our haunted house however I use aluminum duct tape in strips on cardboard like yours but then use thin double sided foam insulation (for insulating windows &amp; doors etc.) to separate the 2. It works great and you can make it much bigger without having to worry about the middle becoming bowed and giving a constant short. Picture a tic tac toe board with a border as the strips of foam insulation.
Nice instructable. If you use arduinos, another option is to use ultrasonic sensors to detect people. They can be had on ebay for as little as $1 a piece! (amazing, isn't it?)
But then you need an Arduino which is more than $1.
naw going old school is way better. plus when yr done u can recycle the aluminum 4 money as well.
Awesome this will help so much!

About This Instructable




Bio: My name is Jason Poel Smith I am a Community Manager here at Instructables. In my free time, I am an Inventor, Maker, Hacker, Tinker ... More »
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