“This project is for a homemade chronograph and this device is used to measure muzzle speed which basically is the speed of bullets. If you remember, a few weeks ago I’ve made a coil gun project, which by the way was very powerful and I recommend you to watch that video as well. Anyway, if I want to know the speed of that metal projectile, I need such project. Basically, this device will measure the time between the input and output of the bullet and will give us the speed in meters per seconds. Is a very easy to make project, but I hope you will learn something new. I will show you what we need to make it, the schematic, the code, how to assemble everything and then we will test it out and see if it works. So guys, let’s get started.
My first idea was using lasers, one LDR sensor and mirrors. But the mirrors were absorbing the light from ther lasers too much. So at the end of the beam, the LDR wasn’t receiving any more light. So I had to change my idea. We need a series of around 7 LDRs connected to a comparator module. THis will give a HIGH oir LOW output to the Arduino. We need the lasers, the 3D printed files, a battery and a charger and wires. We also need a 7 segment display to show the speed. Check the list below.”