Sound Sensing Instructables Robot

This sound-sensitive Instructables robot has eyes that light up when it senses sound!

If I'm being honest, my inspiration for this came when I was looking around a local store and found a similar (but very overpriced) version of this project, and figured that it would be much easier to simply make this at home. Not only is this much more affordable, but there's a lot of room for customization-- e.g. changing the positions of the lights, or even substituting it for a buzzer or motor, or pretty much anything you like.

One main aspect of this project is that I wanted to find a way to make sound-sensitive circuits simpler, so they could work without a microcontroller (however, if you would like to use one, there's an Instructable here for that!). It's a great showpiece, and quick to assemble (it took me ~25 minutes).

1. 1x printed instructables robot template (pdf download below)
2. 4x 1.5v batteries + battery holder
3. 1x breadboard
4. 2x LEDs (red)
5. 2x 120 ohm resistors
6. 1x sound sensor
7. 2x male-male jumper wires
8. 7x male-female jumper wires
9. cardboard (should be ~5 by 3 inches approximately-- for this, I simply used a small box with the top cut off.)
10. glue (any type)
11. tape
12. screwdriver (to adjust sensor)

Make the following connections for your sensor pins, using male-female jumper wires:

VCC pin --Connect the pin to the positive rail

Ground pin -- connect this to the negative rail.

Output pin-- connect to any of the row pins on the breadboard. In the next step, we will connect this pin to our LEDs, the 'output' of our circuit.

On the same row as the output pin of the sensor, connect two 120 ohm resistors. Then, using the male-female jumper wires, connect the LEDs to the other end of the resistor.

Connect the negative and positive rails to the negative and positive of the battery, respectively.

If you notice your LEDs are lighting up even in the absence of sound (or the opposite, they aren't lighting up at all), use a screwdriver to turn the sensitivity knob (see image above) until the LED reacts to sounds.

Cut out the eyes and middle button of the robot. Test to make sure your LEDs fit in the eye hole, and the sensor fits through the middle button.

Glue your cardboard stand/box to the paper cutout. If the hole for the sensor is covered by the cardboard, cut a small hole for it (reference the image).

Insert the LEDs and Sensor into their designated holes. If needed, tape the components into place. Then, slide the breadboard and batteries onto the cardboard stand.

Time for testing your robot!!!!

Try it with different sounds, adjust the sensitivity, add more LEDs, a buzzer, ect. -- pretty much anything you want!