Build a spooky effect with this cool tutorial from guest contributor Carolyn Miller. Thanks for the chills, Carolyn!
It’s Halloween, and your big bright-orange pumpkin bucket is full of delicious candy. You decide to hit that one last house on the left in hopes of finding something really good. As you walk up to the porch, you feel something is not right; it’s just too quiet here.
Then fear takes hold as you start hearing the rustling of leaves nearby. You turn around – nobody is there!
Rustling leaves in a still, overcast Halloween evening are an iconic chill-inducer. How can you make leaves rustle and move at your own haunt without you being there? If you love tinkering with electronics components, the trick is quite simple.
In this article I will show you how. You’re guaranteed to scare the pants off people without terrorizing your bank account. Ready? Let’s get haunting!
What You’ll Need
Before we can begin to frighten unsuspecting folks on Halloween, you will need to pick up a few things. Check out your local Radio Shack or click the orange links.
(Note: always purchase from a locale that allows you to return items in case you don’t quite have the right fit – that’s why we love Amazon!):
|A Passive Infrared Sensor (PIR)|
|(4) 6mm Mini Vibration Motor for Phones, PDA’s and Pagers|
|Enclosed 3 “AA” Battery Holder|
|Any 5 Volt Coil Relay|
|1 K Resistor|
|NPN Transistor (2N2222)|
- You will also need a soldering iron and any protective equipment for your surfaces.
Get Your Soldering Gear Fired Up!
To begin this project, you will solder the red (+5V) wire from the battery holder to the pin that represents +V on the PIR. This will be your 4.5V intake to the sensor.
The black wire of the battery holder will be soldered to the Pin that represents ground – or GND. This will power the sensor once turned on. The pin that says “Signal” is your output signal that says an object is there! This signal turns on when an object is close.
Next, run a wire from the signal to the transistor. The transistor will have 3 prongs on it. One will be wired for your input or the “Signal”. The other prong will be sent to ground or connected to the black wire on the battery holder. The final wire off the transistor will go to “Coil” side of your relay. The other half of the relay side coil will finally be wired back to the GND or Black wire of your battery box.
The drawing shows the basic hook up to make the IR sensor stand alone. When choosing the vibration motors, you must find out what power source is required. Most vibration motors will require about 1.2V, so depending on how many motors you have hooked up, will determine what battery or batteries you will need.
Setting Up Your “Rustling Leaves” Effect
Once everything is connected up, you should be able to turn the power on and the IR motion sensor will detect your movement up close to it. If you want to aim the sensor or cover just one area you can place it in the bottom of a tin can.
Drill a hole in the bottom of the can, run the wires through and use double sided tape to secure the PIR sensor at the bottom of the can. Now you can aim any direction and the sensor won’t trip off from any side motions.
When placing the noise-making vibration motors, it’s best to keep these hidden so they do not get stepped on or damaged. When building this concept, the motors were placed within a group of leaves just off of the porch. The tin can and PIR sensor was hidden away inside the mailbox.
When unsuspecting trick-or-treaters came to the front porch, the sensor picked up the motion right at the stairway. A pile of leaves would begin to shake just off the porch, giving both kids and parents a sudden fright!