Control Halloween Effects with DIY Infrared Remote Controls

• Almost any infrared remote can be used to activate the receiver module. You can just use any old remote that you have lying around your house. Or you can make it a little more fun and you can use specialty TV remotes that are made in the shape of magic wands, sonic screwdrivers, or phasers. But as fun as that would be, I decided to make my own remote from scratch.
• To make a really basic infrared remote, all you need to do is hook up an infrared LED to the square wave signal generator. So I built a simple circuit using a 555 timer IC.
• Pin 4 and 8 on the chip connect to the positive output wire of a battery pack. Pin 1 is connected to the negative output wire of a battery pack. Pins 2 and 6 are connected together. Then a 0.02 microfarad capacitor is connected between pin 2 and pin 1 (ground). A 1 kOhm resistor is connected between pin 2 and pin 3. Lastly an infrared LED and a 22 ohm resistor are wired in series between pin 3 and pin 1 (ground). Be sure to use a 22 ohm resistor that is rated for at least 1/4 watt, or it might overheat.
• When turned on, the LED will begin to blink at a frequency of about 36 kHz.

• When constructing any new circuit, it is a good idea to first prototype the circuit on a breadboard. This gives you a chance to test it out and make any necessary changes before you solder it all together. To quickly test the performance of your circuit you can just point it at the receiver circuit and see if it registers the circuit. The Arduino Serial Monitor tool can be very useful when testing and troubleshooting.
• Once everything is working properly, you can solder the parts onto a piece of perfboard. To help conserve space, I trimmed off the unused sections of the circuit board to make it smaller. I also put heat shrink tubing on the LED to help narrow the output beam and make it more directional.
• I decided to connect the LED with long jumper wires. That way I would have more options as to where I would be able to mount the rest of the circuit. For instance, you could keep the battery and the circuit board in your pocket and hide the LED inside your sleeve or in a glove.

• Remote controls are cool but they don't look very mysterious, so it's a good idea to hide both the transmitter and receiver of your remote system from view. That way the effects look more impressive.
• Fortunately the infrared signal can pass right through most thin materials. So you can easily cover up the transmitter and receiver with paper or fabric and it will still work. You can hide them inside the props or next to them. My favorite way to hide the transmitter is to put it inside a glove. That way the actor can just point at the receiver to activate the props and effects. Because the remote control system isn't visible, it looks like magic or telekinesis.

​Now that you have your remote control system working, it is time to figure out how to use it. There are lots of different effects that you can control. You can activate commercial Halloween props. You can control your own homemade props with servos or linear motors. You can activate sound effects. You can even do things like using an air pump to blow out the candles in a room. The only limitation is your imagination. To help get you started, I am going to show you a few examples in the next steps.

• Most animated props have a "Try Me" button. By connecting to this switch, you can use your Arduino (and your remote) to control the props. If you want a detailed description of how to do this, you can check out the full instructions here on Make:.
• But here is a quick summary. The "Try Me" button activates the prop's animation by connecting a pin on the props control circuit to ground. You can simulate the button being pressed by connecting a transistor in parallel with the switch. When your Arduino sends a HIGH signal to the base of the transistor, it connects the terminals of the switch and activates the prop's animation. Just make sure that you connect the ground of the Arduino to the ground of the prop. You can check this with a multimeter.

• ​Another thing that your remote can control is a servo motor. You can use these motors to turn and move static Halloween props to create your own DIY animated Halloween props. To control a servo, connect the output wires from the servo to the 5V pin, GND pin, and a digital pin on the Arduino (based on the color code of the wires). Connect your servo to a prop (such as a skull) and attach it to a stand to hold it in place. Then write some code to turn on the servo when the IR receiver detects the signal. Here is a simple example.
• #include Servo myservo; // create servo object to control a servo int pos = 0; // variable to store the servo position int inPin = 2; int val = 0; // variable to store the value read void setup() { Serial.begin(9600); // setup serial pinMode(inPin, INPUT); myservo.attach(9); // attaches the servo on pin 9 to the servo object } void loop() { val = digitalRead(inPin); Serial.println(val); // debug value if (val == LOW) { delay(1000); for (pos = 30; pos = 30; pos -= 1) // goes from 180 degrees to 0 degrees { myservo.write(pos); // tell servo to go to position in variable 'pos' delay(15); // waits 15ms for the servo to reach the position } } }

​Another way that you can move props is with a motor and magnets. One set of magnets is embedded in your Halloween prop. Another set of magnets is attached to the end of a linear motor. The motor is mounted to the bottom side of a table. Then the prop is set on top of the table so that the magnets line up. When the receiver circuit detects the signal from your remote, the arm of the motor extends. This causes the prop to move across the table without any apparent cause.

• An easy way to control sound effects with your Arduino is by using a Wave shield. This is a stacking shield that connects directly to the Arduino. For full instructions on how to use the wave shield, you can check out the tutorial on the Adafruit website .
• Here's a quick summary on setting up the Wave shield. Start by recording or downloading some sound files. Then convert these files to mono wave files at 16 bit and 22050 Hz. There are a number of programs and websites that can do this conversion. Name and organize the files. Then drop them onto an SD card and insert it into the shield. Download the waveHC library and copy it into your Arduino libraries directory. Lastly write some code. When your receiver circuit detects the signal from your remote, your Wave shield will play your chosen sound effects.

There are any number of other effects that you can control with this system. You can use a relay circuit to turn appliances on and off. You can hook up an air pump to blow out all the candles in the room. You can even activate full scale animatronics. Use your imagination. If you think of some other fun special effects that you could control with a hidden remote, leave a comment and share.