Millerman's Projects

Acoustic levitation is made possible through the fact that sound behaves as a wave.  When two sound waves intersect each other, they can either constructively or destructively interfere with each other.  (This is how noise-canceling headphones work) This project uses an ultrasonic distance sensor to create a levitation effect.  This works by creating "pockets" where two opposing sound waves interfere with each other.  When an object is placed in the pocket it will stay there, seemingly hovering in place. Materials needed: Arduino board:  https://amzn.to/2DLjxR2 H-bridge:  https://amzn.to/2DXFw7y Distance sensor:  https://amzn.to/2PSbJU2 Breadboard:  https://amzn.to/2RYqiSK Jumper wires:  https://amzn.to/2Q7kiKc Diode:  https://amzn.to/2KlYMf8 Capacitors (Maybe):  https://amzn.to/2DYnCla Original project  from Make Magazine by  Ulrich Schmerold. Step 1: Get Ultrasonic Transmitters You will need to sacrifice a distance sensor for this step

T his is an Arduino controlled rubber band Gatling  gun.  It can hold about 20 rubber bands and it is operated with a USB game controller through processing.  The complete bill of materials can be seen below: Arduino UNO https://amzn.to/2DLjxR2 Jumper cables https://amzn.to/2Q7kiKc Breadboard https://amzn.to/2RYqiSK Servo motors https://amzn.to/2S6E5GZ Gear motor https://amzn.to/2DQUr3u Rubber bands https://amzn.to/2S8zgwR Electrical tape https://amzn.to/2BpvF8a Lego pieces https://amzn.to/2DROMtU Craft sticks (big) https://amzn.to/2zldtuH Craft sticks (small) https://amzn.to/2zldG0X Hot glue sticks https://amzn.to/2TCRND4 Binder clips https://amzn.to/2KnZWa3 Clothespins https://amzn.to/2BpOw2K Cardboard https://amzn.to/2BpOSGC Lazy susan https://amzn.to/2OVr4xH Diode https://amzn.to/2DPaVcn

A speaker works by activating an electromagnet which is nearby a "regular" magnet. This produces vibration, resulting in sound. So if instead of supplying current to the speaker, we can produce current (if very little) by moving the speaker itsself. This current can then be detected and interpreted by a microcontroller such as the Arduino. Step 1: Find a Speaker You will need to find a speaker that you are willing to sacrifice for this project. You can buy one at SparkFun for under a dollar, but you probably already have one somewhere. I used a small speaker from an old pair of headphones, but you can find one almost anywhere - like a musical greeting card or an old alarm clock. Next: Cut a jumper wire in half Strip the ends of it Solder it onto the speaker (there were probably already some wires on there - just cut them off) Alternatively, you could use alligator clips if you have them. Step 2: Build the Circuit  Materials needed: Arduino U