What does your gait look like to your foot? During which part of your gait is the ball of your feet experiencing the most pressure? Is there something wrong with it? Can you fix it by adding or removing material from a custom insole? All these answers can be had with an expensive system and a visit to a podiatrist, but if [Charles Fried] succeeds you can build a similar system at home.
The device works by having an array of pressure sensors on a flat insole inside of a shoe. When the patient walks, the device streams the data to a computer which logs it. The computer then produces a heat map of the person’s step. The computer also produces a very useful visualization called a gait line. This enables the orthotist to specify or make the correct orthotic.
[Charles]’s version of this has another advantage over the professional versions. His will be able to stream wirelessly to a data logger. This means you can wear the sensor around for a while and get a much more realistic picture of your gait. Like flossing right before the dentist, many people consciously think about their gait while at the foot doctor; this affects the result.
He currently has a prototype working. He’s not sure how long his pressure sensors will last in the current construction, and he’s put wireless logging on hold for now. However, the project is interesting and we can’t wait to see if [Charles] can meet all his design goals.
We’re not certain where [NoPleaseDont] got an F-15 Throttle Grip, but it would certainly be a waste not to make something cool out of one. The F-15 is a twin engine air superiority fighter, and in it’s niche, it is one of the most successful ever made. We imagine this makes it a popular choice in air simulators.
Equipped with his successful scrounge [NoPleaseDont] decided to build a full HOTAS, Hands On Throttle and Stick, joystick. He started by taking apart the throttle grip. As each layer was pulled a part, we were pleased to see the reassuring infestation of quality control stamps you’d expect to find on the input of a 26million dollar machine. The pinouts were presumably taken and the handle was reassembled. After that, a lot of custom sheet metal parts, 3D prints, and clever bracketry came together to form the frame of the joystick.
Finally came the electronics. Many of the photos were too blurry to decode, but at minimum a Teensy and custom LED control board is involved. The frame got a few additional buttons and control panels added.
The resulting joystick has a great history, and more buttons than we can guess the purpose of.
Even though VGA is an outdated and becoming somewhat deprecated, getting this video output running on non-standard hardware is a rite of passage for some hackers. [Andrew] is the latest to take up the challenge. He got VGA output on a Freescale i.MX233 and also got some experience diving into the Linux kernel while he was at it.
The Freescale i.MX233 is a single-board computer that is well-documented and easy to wire up to other things without specialized hardware. It has video output in the form of PAL/NTSC but this wasn’t quite enough for [Andrew]. After obtaining the kernel sources, all that’s needed is to patch the kernel, build the kernel, and build a custom DAC to interface the GPIO pins to the VGA connector.
The first thing that [Andrew] did was load up the Hackaday home page, which he notes took quite a while since the i.MX233 only runs at 454 MHz with just 64 MB of RAM. While our retro page may have loaded a little faster, this is still an impressive build and a great first step to exploring more of the Linux kernel. The Freescale i.MX233 is a popular chip for diving into Linux on single-board computers, and there’s a lot going on in that community. There are some extreme VGA hacks out there as well if that’s more your style.
We feel it’s healthy to cultivate a general desire for more neat tools. That’s just one of the reasons we like [doublecloverleaf]’s retro PC mouse. It certainly meets the requirement, the first computer mouse was wooden, and the mouse he used as the guts for this is so retro it belongs in the dollar bin at the thrift store.
To begin with, [doublecloverleaf] took a picture of the footprint of his aged, but trustworthy laser mouse. Using the photo in SolidWorks he built a model of the circuit board, and with that digitized, a mouse that suited his aesthetics around it. The final model is available on GrabCAD.
Edit: Woops, looks like we accidentally slandered a great Slovenian community CNC project. Check out the comments for more info. Original text in italics.
Next came the CNC. It looks like he’s using one of those Chinese 3040 mills that are popular right now. The electronics are no good, but if you luck out you can get a decent set of mechanics out of one. He did a two side milling operation on a wood block, using four small holes to align the gcode before each step, and then milled the bottom out of aluminum. Lastly, he milled the buttons out of aluminum as well, and turned a knurled scroll wheel on his lathe.
The end result looks exceedingly high end, and it would be a hard first guess to assume the internals were equivalent to a $10 Amazon house brand mouse.
Continue reading “Turn Your $10 Dollar Mouse Into A Fancy $10 Dollar Mouse With CNC”
[Andrew Klein] knows the pain of building drawers from plywood. It can be a pain to get all of the pieces measured and cut just right. Then you have to line them up, glue them together, and clamp them perfectly. It’s time-consuming and frustrating. Then one day it hit him that he might be able to make the whole process much easier using a custom saw blade.
The the video below, [Andrew] does a great job explaining how the concept works using a piece of paper. The trick is that the plywood must be cut in a very specific shape. This shape results in the plywood just barely being held together, almost as if it’s hinged. The resulting groove can then be filled with wood glue, and the plywood is folded over on itself. This folding process leaves no gaps in the wood and results in a strong joint. Luckily this special shape can be cut with a specialized saw blade.
This new process removes the requirement of having five separate pieces for a drawer. Instead, only four cuts are needed on a single piece of square plywood. The corners are then removed with a razor blade and all four sides are folded up and into place. [Andrew] shows that his prototype blade needs a little bit of work, but he’s so hopeful that this new invention will be useful to others. Continue reading “Smarter-than-wood Saw Blade Makes Perfect Foldable Joints”
[Jim’s] technique for turning a wireless doorbell into a custom ringtone player is so simple. He manages to get the entire thing done using only a screwdriver and wire clippers as tools. But if you’re looking to use this over the long-term we’d recommend soldering the connections rather than relying only on the twisted wires.
Above you can see all the components used in the project. The wireless doorbell unit is no different from most battery-operated units on the market today. Inside the Radio Shack box is a recording module that lets you play up to 20 seconds of audio. This is powered by the 9V battery on the right. [Jim] removes the speaker from the doorbell and clips off one of the wires that connected it to the board. This is reused as the ground connection for the recording module. The other speaker wire is connected to the ‘Play’ button on the module’s PCB. That’s it, just record your custom sound and pack everything back into the doorbell’s case. You can see the entire hack and hear a demonstration after the break.
Continue reading “Simple hack plays any sound as your door chime”
As the most direct interface between computer and programmer, keyboards can be a deeply personal, sometimes almost religious thing. Some find solace in their vintage IBM Model M, or luxurious leather keyboard, but maker [Carol Chen] took things into her own hands, quite literally. [Carol]’s Maker Faire exhibit has a half dozen specimens of interesting commercial tactile and ergonomic options…but [Chen]’s personal keyboard, where she commits to her work as a full-time coder, has been made to her own exacting specifications.
Continue reading “BAMF2011: Keyboards built from scratch”