One of the major reasons anyone would turn to a 3D printer, even if they have access to a machine shop, is that there are some shapes that are not possible to make with conventional “subtractive manufacturing” techniques. There are a few more obvious reasons a lot of us use 3D printers over conventional machining such as size and cost, but there’s another major reason that 3D printers are becoming more and more ubiquitous. [Crumbnumber1] at Make Anything’s 3D Printing Channel shows us how powerful 3D printers are at iterative design with his air-powered tops. They incorporate fan blades that allow you to spin the top up to very high speeds by blowing air down onto it.
Iterative design is the ability to rapidly make prototypes that build and improve upon the previous prototype, until you’re left with something that does the job you need. Even with a machine shop at your disposal, it can be expensive to set up all of the tooling for a part, only to find out that the part needs a change and the tooling you have won’t work anymore. This is where 3D printers can step in. Besides all of their other advantages, they’re great for rapid prototyping. [Crumbnumber1] made a box full of tops and was able to test many different designs before settling on one that performed above and beyond everything that came before it.
The video below is definitely worth checking out. The design process is well documented and serves as a great model for anyone looking to up their rapid prototyping game.
Many of us have had a radio controlled car at some time in our youth, though it’s probable that none all of us entirely mastered it. There are memories of spectacular crashes, and if we were really unlucky, further boosts to Mr. Tamiya’s bank balance as fresh parts had to be fitted.
[Paul Yan] was watching his young son with a radio controlled toy, and was struck by how the two-joystick control layout is not necessarily as intuitive as it could be. By contrast when faced with a console game with first-person view and a steering wheel the boy had no problem dropping straight into play. This observation led him to investigate bringing a console steering wheel to an RC car, and the result is a rather impressive FPV immersive driving experience.
His build took a PS2 steering wheel peripheral with pedals and mated it to an Arduino Uno via a PS2 shield. The Uno talks to a Nordic NRF24L01 RF module, which communicates with another NRF24L01 on the car. This in turn talks to a car-mounted Arduino Micro, which controls the car servos and speed controller.
FPV video is provided by a miniature camera and transmitter from the world of multirotor flying which is mounted on the car and transmits its pictures over 5GHz to a set of monitor goggles. Sadly he does not appear to have posted any of the software involved, though we doubt there is anything too challenging should you wish to try it for yourselves.
The video below shows the car in action, complete with an over-enthusiastic acceleration and crash from his young son. He tells us it’s a similar experience to playing a racing kart game in the real world, and having seen the video we wish we could have a go.
[Markus Gritsch] and his son had a fun Sunday putting together a little toy airboat from a kit. They fired it up and it occurred to [Markus] that it was pretty lame. It went forward and sometimes sideward when a stray current influenced its trajectory, but it had no will of its own.
The boat was extracted from water before it could wander off and find itself lost forever. [Markus] did a mental inventory of his hacker bench and decided this was a quickly rectified design shortcoming. He applied a cheap knock-off arduino, equally cheap nRF24L01+ chip of dubious parentage, and their equivalent hobby servo to the problem.
Some quick coding later, assisted by prior work from other RC enthusiasts, the little boat was significantly upgraded. Now the boat could be brought back to shore using any R/C controller that supported the, “Bayang,” protocol. He wouldn’t have to face the future in which he’d have to explain to his son that the boat, like treacherous helium balloons, was just gone. Video after the break.
For those wondering why [Atarity] would go to this much trouble to test arcade buttons, we suspect an ulterior motive – skip to the 21:14 mark of the long video below to see the real design inspiration. Regardless of the motive, there’s no doubting the care that went into the build – CNC-milled birch case, extremely detailed laser-engraved graphics, and a carbon-fiber back plate covered with suede, because suede. We especially like the detail on the speaker grill: the embroidered fabric and puffed-up look really works with the rest of the design, including the leather hand strap.
It’s not entirely clear from the post what the end goal of the testing is, but we assume it’ll be some sort of MAME build. In which case, [Atarity] might want to check out our recent articles on a tabletop MAME cabinet or this portable MAME rig. But whatever he comes up with, we’re sure the craftsmanship will be there.
It always seems odd to us that magnetic levitation seems to only find use in big projects (like trains) and in toys. Surely there’s a practical application that fits on our desktop. This isn’t it, but it is a cool way to turn a cheesy-looking levitating globe into a pretty cool Star Wars desk toy.
As projects go, this isn’t especially technically challenging, but it is a great example of taking something off the shelf and hacking it into something else. The globe covering came off, revealing two hemispheres. A circular hole cut out and inverted provides the main weapon. Some internal lighting and small holes provide light. Some fiber optic sanded and tinted green make the weapon fire. The rest is all in the painting.
There’s even a tiny imperial ship orbiting the killer man-made (or is that Sith-made) moon. If you want a bigger challenge, you might try bamboo. Or you can go minimalist and let your eyes and brain do most of the work.
Here at VCF, we stumbled across a gigantic contraption that spanned several tables. Rube Goldberg machine this was not. Instead, this device actually does something useful! [Tim Robinson’s] differential analyzer can solve differential equations through several stages of mechanical integrators. The result is a pen-plot graph of the solution to the input equation, input by displacing a rod as a function of time.
Differential analyzers have been around for over a century. [Tim’s] claim to fame is that this particular DA is constructed entirely from Meccano-branded parts. We’re thrilled to see Meccano, over 100 years old at this point, continue to find new uses outside the toy box.
The differential analyzer is riddled with mechanisms that are bound to swing some heads for a double-take. Since the input shaft that transmits the input function f(x), has very little friction, the result can only be carried through the remainder of the machine with some means of torque amplification. To do so, [Tim], and most other DA designers implement a torque analyzer. For [Tim], though, this feat proved to be more difficult (and more triumphant) than other solutions, since he’s using a set of parts that are entirely from Meccano. In fact, this feature took [Tim] through about 20 iterations before he was finally satisfied.
VCF West continues to run through the end of the weekend at the Computer History Museum in Mountain View, CA. If you haven’t already packed your bags for DEF CON, stop by for a few more bewildering brain teasers.