We’re not sure that it’s absolutely necessary to raise ducks using a remote-control animatronic duck decoy, but people have stranger hobbies.
This YouTube video (embedded below) from [Imaginative Guy] chronicles an impressive feat of RC animatronics, sparing no effort to make the RC duck “parents” realistic. There’s a ton of detail in the videos, from the machining of small necessary bits to the liberal application of hot glue where necessary. Continue reading “Ducklings Raised By Remote”
If one of the design goals of [wsw4jr]’s portable solar battery bank build was to make something that the local bomb squad would not hesitate to detonate with a water cannon if he leaves it unattended, then mission accomplished.
We kid, but really, the whole thing has a sort of “Spy vs. Spy” vibe that belies its simple purpose. A battery bank is just an array of batteries, some kind of charge controller, and an inverter. The batteries are charged by any means possible – in this case by a small array of solar panels. The mains output of the inverter is used to power whatever doodads you have.
[wsw4jr] didn’t mention of the inverter specs, but from the size of the batteries and the wiring – both of which he admits are not yet up to snuff in his prototype – it’s a safe guess that the intended loads are pretty small. Tipping the scale at 60 pounds, the unit tends toward the luggable end of the portability scale. Still, this could be a great tool for working out in the field, or maybe even tailgating.
We’ve seen expedient battery banks and emergency power from cordless drill batteries before, but this build is quite a bit more sophisticated. We’ll be watching for updates on this one.
We have a love/hate relationship with LiIon batteries. They pack all this power in such a small and light package. But for running 3.3 V devices, they’re cumbersome. They need to be stepped down a little bit when they’re fully charged at 4.2 V, but then they need to be stepped up at the end of their charge around 3.0 V.
A simple boost or buck converter can’t do both jobs, although you’d be tempted because they can be purchased for peanuts online. So [Kirich] hacked cheap boost converters into the more capable SEPIC topology, which sell for nearly 10x as much. (Google translated version here.) The bottom line? With a little desoldering, a cut trace here and an extra inductor there, and [Kirich] had a very capable circuit that would maintain a constant 3.3 V output when the input swung between 1 V and 5 V.
If SEPIC power converters are foreign to you, have a read through Maxim’s white paper on the subject. Basically, it’s a boost converter with a capacitor in the middle that lets the output voltage drop below the input voltage. An extra inductor keeps the output side of this capacitor at ground potential (on average).
If you want more detail, [Kirich] doesn’t disappoint. He tested his modifications in multiple configurations on two different models of boost converter. As you’d expect with power circuitry, layout and trace length matters, and [Kirich] took good notes. This is a great read for the frugal hacker, or anyone who’s interested in boost/buck converters.
Speaking of boost/buck circuits, we’ve got some more links for you. This video from Sparkfun’s [Pete Dokter] is worth fifteen minutes, and if you want to get your hands really dirty in the construction of such circuits, this ATtiny-based boost converter circuit is fun to play with.
Thanks [kirillre4] for the great tip!
Lithium-Ion batteries are finicky little beasts. They can’t be overcharged, overdischarged, overheated, or even looked at funny without bursting into flames. Inside any laptop battery pack, a battery charge controller keeps watch over all the little cells, and prevents them from getting damaged.
Of course, any “smart” device will sometimes make the wrong choices, and then it’s up to us to dig inside its brains and fix it. When [Viktor] got a perfectly good battery pack with a controller that refused to charge the batteries, he started off on what would become an epic journey into battery controllers, and the result is not just a fixed battery, but a controller-reprogramming tool, software, and three reversed controller chips so far.
Battery controller chips speak SMBus, and [Viktor] started out by building a USB-SMBus tool. It’s a clever use of a cheap eBay development board for a Cypress CY7C68013A USB microcontroller. Flashed with [Viktor]’s firmware and running his software on the host computer, a SMBus scan is child’s play.
The rest of the story is good old-fashioned hacking: looking for datasheets, reading industry powerpoints, taking wild guesses, googling for passwords, and toggling the no-connect pins while booting the controllers up. We’re not going to argue with results: the bq8030, R2J240, and M37512 controllers have all given up their secrets, and tools to program them have been integrated into [Viktor]’s SMBusb tool.
In short, this is one of the nicest hard-core hacks we’ve seen in a while. Kudos [Viktor]! And thanks for the SMBus tool.
[Dave Hrynkiw] wrote up some practical and useful detail around embedding electronics into clothing. It centers around his daughter’s “Starry Night” high school graduation dress, which is the culmination of a lot of experimentation in finding the best way to do things. His daughter accented the dress with LEDs to produce a twinkling starfield effect, and a laser-cut RGB pendant to match.
While [Dave] is the president of Solarbotics and pitches some products in the process of writing it all up, the post is full of genuinely useful tips that were all learned though practical use and experimentation. Imagine how awesome it must be growing up a child of a “local technology-hacking company” founder — akin to growing up as Willy Wonka’s progeny.
What advice does [Dave] have for making electronics an awesome part of garments? For example, the fact that regular hookup wire isn’t very well suited to embedding into clothing due to the need for high flexibility. There is also the concept of sequestering electronics into a separate Technology Layer — a must for anything that will be used more than once. The idea is to “build your technology so it can be isolated from the fashion aspect as much as possible. It makes building and maintenance of both the fashion and technology aspects much simpler.”
Slapping some LEDs and a battery pack into clothing might do the trick if all you care about is some bling, but if you want something that actually highlights and complements clothing while also being able to stand up to repeated use, this is a great read. A simple lighting effect that complements a design isn’t difficult, and there’s no need to reinvent the wheel or make the same mistakes others have encountered. Video is embedded below.
Continue reading ““Starry Night” Dress Shines On The Experience Of Multiple Builds”
This is just good, clean fun. Well, maybe not clean since this souped-up racing Roomba appears to move too fast to actually clean anything anymore. But did they ever really clean very well in the first place?
[Roland Saekow] doesn’t offer much in the way of build details, but the starting point was a 10-year old Roomba Discovery. The stock motors were replaced with 600RPM planetary drive motors and a whopping 12A motor controller. The whole thing is powered off the standard Roomba 14.4V battery pack, but we suspect not for long. Those motors have got to suck down the juice pretty fast to be able to pop wheelies and pull hole shots like it does in the video below.
No word either on how it’s being controlled; our guess is RC, since it looks like the collision sensor grazes a chair leg slightly around the 0:33 mark, but doesn’t seem to change direction. It’d be cool if it could operate autonomously, though. We wonder how it would deal with the Virtual Walls at those speeds.
File this one under “Just for Fun” and maybe think about the possibilities for your defunct Roomba. If speed-vacuuming isn’t your thing, there are plenty of other Roomba hacks around here.
Continue reading “Racing Roomba Packs The Power To Pop Wheelies”
Warranty? We don’t need no stinking warranty! We’re hackers, and if you have access to a multi-million dollar CNC machine and 3D CAM software, you mill your own headphone replacement parts rather than accept a free handout from a manufacturer.
The headphones in question, Grado SR325s, are hand-built, high-end audiophile headphones, but [Huibert van Egmond] found that the gimbal holding the cups to the headband were loosening and falling out. He replicated the design of the original gimbal in CAM, generated the numeric code, and let his enormous Bridgeport milling machine loose on a big block of aluminum. The part was drilled and tapped on a small knee-mill, cut free from the backing material on a lathe, and bead-blasted to remove milling marks. A quick coat of spray paint – we’d have preferred powder coating or anodization – and the part was ready to go back on the headphones.
Sure, it’s overkill, but when you’ve got the tools, why not? And even a DIY CNC router could probably turn out a part like this – a lot slower, to be sure, but it’s still plausible.
Continue reading “High-end Headphones Fixed With High-end CNC Machine”
