Dodgey99 built an Arduino-powered Etch-a-Sketch clock, in which a pair of stepper motors painstakingly draw out the current time. It's got a very low refresh rate, though: the limits of the motors and the Etch-a-Sketch means that it takes more than a minute to display the time, and it needs a couple of minutes' rest between each number. There's a plan to accelerate things with some beefier motors.
I use an Arduino driving two very cheap darlington stepper drivers with 64:1 internally reduced steppers for the drawing. For the rotation I'm using an Easy-Driver driving a Nema 17 stepper.
I also have a DS1307RTC real time clock installed so it always knows the time. Setting the time is a one-off via USB connected to a PC. Once done, you un-tether, and then the RTC keeps the time, for up to a year on the rechargeable battery, or so I'm told...
The code is actually very simple, it's just a pain drawing the numbers!
The G clamp on the back is for a counter balance until I find something more elegant!
The steppers are far too slow to write the time in under a minute so I delay it for a couple of mins between each draw. Mostly to give the very hot motors a while to cool off and to give the etch a sketch a break!
Etch a Sketch clock powered by Arduino
Zero-knowledge proofs are one of the most important concepts in cryptography: they’re a way to “validate a computation on private data by allowing a prover to generate a cryptographic proof that asserts to the correctness of the computed output” — in other words, a way to prove that something is true without learning the details.
Retroworks’ $18 decoder rings don’t have much by way of cryptographic robustness (they compare disfavorably to the cipher-wheel wedding rings my wife and I wear!), but they’re not a bad way to introduce the littlies in your life to the idea of habitual secrecy. (via Red Ferret)
This week (and next due to the nature of different release dates for the direct market and the book market) marks the release of the first collection of SHADE THE CHANGING GIRL v.1: Earth Girl Made Easy, which compiles issues 1-6 (previously). It’s a heavy load to recreate a character that giants before you have written. Steve Ditko is a master of the strange. His mind a merry-go-round of experimentation.
The Fader Stealth Quadcopter from TRNDlabs packs incredible flight performance into a package small enough to land on your phone screen, and it’s available now in the Boing Boing Store.The Fader’s six-axis gyroscope module gives it perfect balance in the air. This makes the onboard 720p HD camera all the better for shooting amazing flight […]
Although fully autonomous vehicles aren’t yet allowed on public streets, they are poised to dominate the roads in the not-too-distant future. But before that happens, Apple, Google, Uber, and other companies now investing in self-driving tech are going to need talented developers that can account for the dizzying array of factors at play when a […]
The PiCar-V learning kit comes with everything you need to build a Python-powered robot, and it’s currently being offered in the Boing Boing Store.