[Dirk] shared a fascinating project of his that consists of several different parts coming together in a satisfying whole. It’s all about wanting to do target practice, indoors, using a simple red laser dot instead of any sort of projectile. While it’s possible to practice by flashing a red laser pointer and watching where it lands on a paper target, it’s much more rewarding (and objective) to record the hits in some way. This is what led [Dirk] to create human-powered, battery-free laser guns with software to track and display hits. In the image above, red laser hits on the target are detected and displayed on the screen by the shooter.
There are several parts to this project and, sadly, the details are a bit incomplete and somewhat scattered around, so we’ll go through the elements one at a time. The first is the guns themselves, and the star of the show is his 3D printed cowboy rifle design. The rifle paints the target with a momentary red laser dot when the trigger is pressed, but that’s not all. [Dirk] appears to have embedded a stepper motor into the lever action, so that working the lever cranks the motor as a generator and stores the small amount of power in a capacitor. Upon pulling the trigger, the capacitor is dumped into the laser (and into a piezo buzzer for a bit of an audio cue, apparently) with just enough juice to create a momentary flash. We wish [Dirk] had provided more details about this part of his build. There are a few more images here, but if you’d like to replicate [Dirk]’s work it looks like you’ll be on your own to some extent.
As for the target end of things, blipping a red dot onto a paper target and using one’s own eyeballs can do the job in a bare minimum sort of way, but [Dirk] went one further. He used Python and OpenCV with a camera to watch for the red dot, capture it, then push an image of the target (with a mark where the impact was detected) to a Chromecast-enabled screen near the shooter. This offers much better feedback and allows for easier scoring. The GitHub repository for the shot detector and target caster is here, and while it could be used on its own to detect any old laser pointer, it really sings when combined with the 3D printed cowboy rifle that doesn’t need batteries.
Not using projectiles in target practice does have some benefits: it’s silent, it’s easy to do safely, there is no need for a backstop, there are no consumables or cleaning, and there is no need to change or patch targets once they get too many holes. Watch it all in action in the video embedded below.
This project by [blackfish] shows off a cardboard lookalike of an MP5 that loads from a working magazine, has a functional charging handle, and flings paper projectiles with at least enough accuracy to plink some red party cups. It was made entirely from corrugated cardboard, paper, rubber bands, and toothpicks.
In the video (embedded below) you can see some clever construction techniques. For example, using a cyanoacrylate adhesive to saturate areas of wood, cardboard, or paper to give them added strength and rigidity. The video is well-edited and worth a watch to see the whole process; [blackfish] even uses a peeled piece of cardboard — exposing the corrugated part — as a set of detents (6:56) to retain the magazine.
[Mathieu] wrote in with his laser target practice game. It’s not the most amazing hack in the history of hackery, but it’s an excellent example of the type of simple and fun things you can do with just a little bit of microcontrollering.
First off, the gun is a broken toy gun that used to shoot something other than red collimated light beams. The Arduino knockoff inside reacts to a trigger pull and fires the laser for around 200 milliseconds. The gun also has a “gas gauge” that fills up with repeated shots and cools down over time. And therein lies the game — a simple race to ten, where each player only has a fixed number of shots over time.
The targets are simply a light sensor, scorekeeping LED display, and a buzzer that builds tension by beeping at you as the countdown timer ticks down. The bodies are made out of 3D-printed corners that connect some of [Mathieu]’s excess wooden goat-cheese lids.
All the code is up on GitHub so you can make your own with stuff that you’ve got lying around the house. The “gun” can be anything that you can embed a laser in that makes it aimable. Good clean fun!
[Cowboy Bob] of Making Stuff decided he needed a practice target, and wanted to make it a bit more interesting than throwing up some beer cans on a fence. He’s created a highly durable 10-target “Robo-Target” which can be remote controlled or automated. A thick piece of 1/4″ angle steel makes up the main frame of it, so if you’re practicing with hand guns it’ll take the abuse. If you’re just using an air soft or paintball gun you probably don’t need to make it this beefy.
Five servo motors swing paper five targets back and forth on 3D printed swing arms — and since each target has a front and a back side, it gives you 10 different things to shoot at. In challenge mode it’ll even show you two targets at a time which will require you to quickfire in order to get both!