Autonomous Vehicle-Following Vehicle

Humanity has taken one step closer to Skynet becoming fully aware. [Ahmed], [Muhammad], [Salman], and [Suleman] have created a vehicle that can “chase” another vehicle as part of their senior design project. Now it’s just a matter of time before the machines take over.

The project itself is based on a gasoline-powered quad bike that the students first converted to electric for the sake of their project. It uses a single webcam to get information about its surroundings. This is a plus because it frees the robot from needing a stereoscopic camera or any other complicated equipment like a radar or laser rangefinder. With this information, it can follow a lead vehicle without getting any other telemetry.

This project is interesting because it could potentially allow for large convoys with only one human operator at the front. Once self-driving cars become more mainstream, this could potentially save a lot of costs as well if only the vehicle in the front needs the self-driving equipment, while the vehicles behind would be able to operate with much less hardware. Either way, we love seeing senior design projects that have great real-world applications!

Continue reading “Autonomous Vehicle-Following Vehicle”

Spline Thieving Makes Hobby Servos Even More Useful

For years the proprietary spline pattern of rc servos has been a dealbreaker for hobbyists who want to add custom shafts and gears to their servos. First, different servo sizes have different spline sizes, and each vendor equips their servos with different patterns. True, some special vendors sell custom gears that mate to these patterns, but, overall, the hard-to-replicate pattern has severely limited the output options for servos.

This pattern didn’t deter [JB], however. With some clever CAD skills, and two working implementations, he’s demonstrated that these spline patterns can be (1) harvested and (2) added into custom components, opening a new suite of design opportunities involving servos.

To capture the spline, [JB] imports an image into Solidworks, and traces the pattern on a properly scaled image. From there, he can embed this pattern directly into a physical model for fabrication.

To make parts that preserve this pattern, [JB] has two options. With his FormLabs printer, he can print components that already have the pattern feature, allowing him to press-fit custom links directly onto servos. Alternatively, for a sturdier component, he presents the milling method. With this technique, he drills a circle of bolt holes onto the desired output shaft and then mills out the center. From here, the shaft can also be directly pressed onto the servo spline where each spline groove fits snugly into the edge of the previously-drilled holes.

So, how well do they work? According to [JB] he’s actually managed to do some damage to himself before damaging to the 3D-printed part while trying to strip the pattern. The end-goal is to insert these shafts into transmissions for a miniature combat robot, another one of [JB’s] projects which is well-underway. Until then, we’re looking forward to seeing more servos tightly-integrated into upcoming projects.

Emergency Power Based On Cordless Drill Batteries

[Don Eduardo] took matters into his own hands after experiencing a days-long power outage at his house. And like most of us have done at least one, he managed to burn his fingers on a regulator in the process. That’s because he prototyped a way to use power tool batteries as an emergency source — basing his circuit on a 7812 linear regulator which got piping hot in no time flat.

His next autodidactic undertaking carried him into the realm of switch-mode buck converters (learn a bit about these if unfamiliar). The device steps down the ~18V output to 12V regulated for devices meant for automotive or marine. We really like see the different solutions he came up with for interfacing with the batteries which have a U-shaped prong with contacts on opposite sides.

The final iteration, which is pictured above, builds a house of cards on top of the buck converter. After regulating down to 12V he feeds the output into a “cigarette-lighter” style inverter to boost back to 110V AC. The hardware is housed inside of a scrapped charger for the batteries, with the appropriate 3-prong socket hanging out the back. We think it’s a nice touch to include LED feedback for the battery level.

We would like to hear your thoughts on this technique. Is there a better way that’s as easy and adaptive (you don’t have to alter the devices you’re powering) as this one?

Continue reading “Emergency Power Based On Cordless Drill Batteries”

Rocking A New Sound For Guitar

We’ve seen inventive sound hacking from [Jeremy Bell] before on Hackaday. You may remember reading a few months ago about how he invented a new way to produce that familiar effect DJs create when scratching records. By clipping samples from cassette tapes and stretching them across a set of short rails, he was able to refashion the audio pickup to glide over the tape at his fingertips. With a clothes pin wrapped in strips of foil teetering over a contact, he had a responsive tactile switch to aid in producing the cutting needed to carve out a beat.

Since then, [Jeremy] has been evolving this same switch concept and testing out new applications for it. The most recent of which he appropriately referrers to as the “Rocker”. With an electric guitar as a starting point, [Jeremy] uses a similar switching technique to bounce back and forth between two audio signals. The first of which being the sound produced in real-time by hammering on the frets of the guitar, and the second channel having a slight delay. By leveraging the glitchy effect created when switching between the two channels he is able to produce a sound all its own.

The prototype seen in his video is table-bound like the early versions of his Scrubboard, yet he’s able to play one-handed with the guitar and demo his device like a cake walk. It’d be fantastic to see this quirkiness and ingenuity taken to the level of his previous hack, leading to a stand-alone add-on for the guitar. Either way, this is yet another great example of sound play:

Continue reading “Rocking A New Sound For Guitar”

CNC Plotter Uses Only The Good DVD Drive Parts

It wasn’t that long ago that wanting to own your own 3D printer meant learning as much as you possibly could about CNC machines and then boostrapping your first printer. Now you can borrow time on one pretty easily, and somewhat affordably buy your own. If you take either of these routes you don’t need to know much about CNC, but why not use the tool to learn? This is what [Wootin24] did when building a 3D printed plotter with DVD drive parts.

Plotters made from scrapped floppy, optical drives, and printers are a popular hand, and well worth a weekend of your time. This one, however, is quite a bit different. [Wootin24] used the drives to source just the important parts for CNC precision: the rods, motors, motors, and bearings. The difference is that he designed and 3D printed his own mounting brackets rather than making do with what the optical drive parts are attached to.

This guide focuses on the gantries and the mechanics that drive them… it’s up to you to supply the motor drivers and electrical side of things. He suggests RAMPS but admins he used a simple motor driver and Arduino since they were handy.

Paper Cutter Becomes A Laser Engraver

Small and powerful laser diodes are getting cheaper and cheaper, and there are a few commercial products that give anyone the ability to cut paper and vinyl with a computer-controlled cutting machine. What happens when you combine the two? The beginnings of a hacked together laser engraver.

For this build, [Peter] is using a Silhouette Portrait, a desktop CNC cutting machine that’s usually used for vinyl decals and intricately cut paper crafts. This machine isn’t limited to mere decorative crafts – it’s been used for cutting PCB stencils and other pseudo-industrial tasks.

Because the Silhouette Portrait has an interface that allows just about any CAM software to control it, the only thing [Peter] needed to make for his experiments in laser engraving was a mount to hold the laser diode. Luckily, the laser had a similar form factor to the cutting blades for the machine, and a bit of tape held everything together.

Focusing the laser was done by unscrewing the lens, and with a bit of trial and error, [Peter] was able to make a few marks in the material of his choice. This isn’t a laser cutter, but with a little more work it will make a fantastic laser engraver.

Continue reading “Paper Cutter Becomes A Laser Engraver”

Solar Tetroon Spooks Albuquerque

An interesting take on Hackerspace outreach is spooking the local community into calling the FAA and even the Air Force. It wasn’t exactly the plan at Quelab, but after an experimental solar tetroon got away from [Gonner Menning], one of the space’s members, that’s exactly what happened.

This is the first we remember hearing of solar tetroons. A tetroon is actually a fairly common weather balloon design using four triangle-shaped pieces. The solar part is pretty neat, it’s a balloon that uses the sun to heat air inside of a balloon. Instead of filling the bladder with a lighter-than-air gas it is filled with regular air and the sun’s rays heat it to become lighter than the surrounding ambient air.

For this particular flight the balloon was never supposed to be off the tether. Previous iterations had turned out to be rather poor fliers. Of course it figures that when [Gonner] finally tuned the design with an optimal weight to lift ratio it slipped its leash and got away. The GPS package tracked it for quite a while but ended up dying and the craft was nary to be found.

We weren’t going to embed the local news coverage video, but at the end the talking heads end up rolling around the word “Hackerspace” in their mouths like it’s foreign food. Good for a giggle after the break.

Continue reading “Solar Tetroon Spooks Albuquerque”