How often after being exposed to Star Wars did you dream of having your own working lightsaber? These days — well, we don’t quite have the technology to build crystal-based weapons, but tailor-made lightsabers like redditor [interweber]’s are very much real.
Piggybacking off the Korbanth Graflex 2.0 kit — a sort of bare-bones lightsaber ready to personalize — [interweber] is using a Teensy 3.5 to handle things under the hilt. Instead of taking the easy route and cramming everything into said handle, a 3D printed a cradle for the electronics and speaker keep things secure. The blade is made up of two meters of APA102 LEDs.
As well as all the sound effects appropriate to ‘an elegant weapon for a more civilized age’, a cluster of buttons handle the various functions; , playing and cycling through music(more on that in a second), changing the color of the lightsaber — Jedi today, Sith tomorrow — enabling a flickering effect that mimics Kylo Ren’s lightsaber, color cycling, and a…. rave mode?
[Richard]’s project is based on the EOgma Neo machine learning library. Using a type of machine learning known as Sparse Predictive Hierarchies, or SPH, the algorithm is first trained with user input. [Richard] trained the model by driving it around a small track. The algorithm takes into account the steering and throttle inputs from the human driver and also monitors the feed from the Raspberry Pi camera. After training the model for a few laps, the car is then ready to drive itself.
Fundamentally, this is working on a much simpler level than a full-sized self-driving car. As the video indicates, the steering angle is predicted based on the grayscale pixel data from the camera feed. The track is very simple and the contrast of the walls to the driving surface makes it easier for the machine learning algorithm to figure out where it should be going. Watching the video feed reminds us of simple line-following robots of years past; this project achieves a similar effect in a completely different way. As it stands, it’s a great learning project on how to work with machine learning systems.
Spot welding should easier than it looks. After all, it’s just a lot of current in a short time through a small space. But it’s the control that can make the difference between consistently high-quality welds and poor performance, or maybe even a fire.
Control is where [WeAreTheWatt]’s next-level battery tab spot welder shines. The fact that there’s not a microwave oven transformer to be seen is a benefit to anyone sheepish about the usual mains-powered spot welders we usually see, even those designed with safety in mind. [WeAreTheWatt] chose to power his spot welder from a high-capacity RC battery pack, but we’d bet just about any high-current source would do. The controller itself is a very sturdy looking PCB with wide traces and nicely machined brass buss bars backing up an array of MOSFETs. A microcontroller performs quite a few functions; aside from timing the pulse, it can control the energy delivered, read the resistance of the 8AWG leads for calibration purposes, and even detect bad welds. The welder normally runs off a foot switch, but it can also detect when the leads are shorted and automatically apply a pulse — perfect for high-volume production. See it in action below.
There may be bigger welders, and ones with a little more fit and finish, but this one looks like a nicely engineered solution.
Rehabilitating brain injuries where a patient’s sense of balance has been compromised is no easy task. Current solutions only trigger when the patient reaches a threshold and by then, it may already be too late for a graceful recovery. [Simon Merrett]’s SoleSense is being designed to give continuous feedback like a stock humans innate sense of balance. Therapists hope this will aid recovery by more closely imitating what most of us grew up with.
SoleSense relies on capacitive sensors arranged under the feet to know where the patients are placing their weight. [OSHPark] is providing the first round of flexible PCBs so some lucky sole is going to get purple inserts.
Outside of recovery, devices like this can teach better posture or possibly enhance a fully functioning sense of balance. That could improve physical performance. Who knows, we are finding new ways of perceiving the world all the time.
No matter what material you work with, the general rule is that with machine tools, the heavier, the better. Some people can’t afford or don’t want big tools, though, even with their natural tendency to reduce vibrations. That doesn’t mean something can’t be done to help the little tools, like reducing vibration in a contractor-grade table saw.
This one might seem a little outside the usual confines of the hackosphere, but nobody can doubt [Matthias Wandel]’s hacker chops and he really shows off his problem-solving skills with this one. His well-worn contractor-style table saw has had more than a few special modifications over the years, some of which left it with a shimmy sufficient to vibrate workpieces right off the table. He fashioned a friction damper for the saw’s motor from wood, complete with ball and socket joints to allow full movement of the blade height and angle. That didn’t quite do the trick, but his incremental approach finally found the right combination of factors, and the video below shows a saw now stable enough to balance a nickel.
Fidget spinners are not only a fad, but pretty much useless. Sounds like a job for hacking to make the toys have some actual purpose. [D777k] took up the challenge and created a MIDI controller from a common spinner. You can see a video of the results, below.
The device uses a LightBlue Bean controller and Garage Band as the MIDI software. Granted, it might not be super useful, but it is better than just a plain old spinner. [D777k] calls it a “whirling dervish of sound making!
The Arduino code that drives the thing is very simple. It reads three axes of acceleration and uses that to drive the MIDI software. When the acceleration exceeds a threshold, the software creates a new note based on the sums and differences of the accelerations.
Before we get ahead of ourselves: no, not that DEF CON. Instructables user [ArthurGuy] is a fan of the 1983 movie War Games, and following a recent viewing –hacker senses a-tingling — he set to work building his own real-time display.
Making use of some spare wood, [ArthurGuy] glued and nailed together a 10x10x50cm box for the sign. Having been painted white already at some point, the paint brilliantly acted as a reflector for the lights inside each section. The five DEF CON level panels were cut from 3mm pieces of coloured acrylic with the numbers slapped on after a bit of work from a vinyl cutter.
Deviating from a proper, screen-accurate replica, [ArthurGuy] cheated a little and used WS2812 NeoPixel LED strips — 12 per level — and used a Particle Photon to control them. A quick bit of code polls the MI5 terrorism RSS feed and displays its current level — sadly, it’s currently at DEFCON 2.