Project: Inexpensive Firearm Accelerometer

Based on the feedback from my previous experiment[1], I wrote an in-depth article about the accelerometer unit I built. In this article, I describe how I built it, how it works, and how you can build your own for under $50! The project is open-sourced and it uses off-the-shelf components. Data analysis was done using Python, Pandas, and Plotly.

I hope that this content is high quality enough to justify the time you spend reading it, and how much time it took me to create it!

I’d love to hear your feedback and answer any questions!

[1] https://news.ycombinator.com/item?id=18731322

You need to rig this up to an actuator. There are lots of things you could do with that.

You could detect when a machine pistol is getting uncontrollable muzzle rise, then stop it until the trigger is released and reapplied.

You could hold off firing until the gun is stable. When the trigger is pulled, look for smooth movement. (no angular acceleration, and the regular acceleration has a stable magnitude equal to gravitational acceleration) The motion for leading a duck is fine, but the motion of stumbling and getting snagged on bushes is not.

You could disable the gun if acceleration goes to zero, for example by being dropped. After half a second of stable gravitational acceleration, reenable the gun.

I’ve played with the adafruit 9DOF sensor on a handgun. It was fun, but trigger pull wasn’t my problem, so I went on to other things.

However, I’ve always idly wondered about mounting a cheap keychain cam to a flashlight mount, then exploiting the rolling shutter effect to extract high frequency rotation information.