Air Raid Siren

thingiverse

UPD2: Added a version of the siren with 5 blades. UPD1: Added a version of the siren with facets that serves as a horn. Perhaps this version will be even louder. Video: https://youtu.be/wPYlO7F923U A compact air raid siren that anyone can make. Simulates the operation of a real siren. In addition to filament, you will need: - 2205 engine for FPV quadcopter (2 pcs); - ESC 25A (2 pcs); - PDB (1 pc); - SY60 or XT60 connector (1 pc) - Arduino Nano (1 pc); - 10 kΩ resistor (1 pc); - tact button (1 pc); - some hardware, wires, heat shrinkage, hot melt glue. I recommend building a version of the siren with 8 and 10 blades, the version with 6 and 10 sounds a little low frequency. It would be possible to increase the speed of rotation of the rotors, but it is already getting scary. :) The main thing is not to use 2 identical rotors in one siren, the real sound of the siren gives the use of different rotors. Also make sure the rotors turn in the correct direction - clockwise. If the direction is wrong, swap any two wires from the motor to the ESC. I also attached the sketch for programming Arduino. It is advisable that you read and understand the algorithm of operation and startup of the device. You may be able to write the sketch more correctly, this is my first experience with Arduino. In short, the siren's algorithm is as follows: - connect the device to the battery; - the device calibrates the ESCs within approximately 30 seconds; - after the last beeps, the device is ready to start, interrogates the start/stop button; - pressing the button for 1 second starts the device, pressing it again stops it. Protect your hearing! Be careful the first time you start the device. Before starting, make sure that the motor speed I have selected is suitable for your siren. Also make sure that the rotors rotate freely, have no wobbling, and are securely fixed to the motor. I also recommend doing the first short start without rotors. Feel free to ask questions, write your suggestions.