Zelo, The Improbable Wooden Trike

The earliest bicycles were made from wood. Nearly two centuries later, some garage tinkerers still turn to this most traditional of materials for their own creations, since welding one requires experience and tools beyond the reach of many. Resembling Gilligan’s Island props, the resulting bikes are both artistic and great fun, but not very practical for real use; often heavy, ill-fitting or lacking durability.

[Boris Beaulant’s] birch laminate Zelo, on the other hand, has cleaner lines than anything you’d see in an IKEA showroom. Not content with an ordinary two-wheeler, he’s tackled a three-wheeled recumbent trike, which requires even finer tolerances. Two months and over 1,300 miles later, the trike is still rolling strong through the French countryside, proving its mettle as legitimate transportation and not just a garage novelty. [Beaulant’s] build log (Google translation here) offers some insights into the development of this masterpiece, starting with prior woodworking projects (furniture, rolling toys and a children’s bike) and finding clever solutions to problems such as creating a mold of his own back for a custom-contoured seat.

DIY 3D Gets A Nod At SIGGRAPH

3dscan

Among the courses at this year’s SIGGRAPH (an annual technical conference and showcase of the latest in computer graphics research) was an introduction to 3D scanning that covers all the bases: mathematical foundations, two different build-your-own hardware approaches, and how to process and render the resulting datasets. The presenters have assembled all the course materials on a top-notch web site featuring slide shows, complete source code, and an extensive round-up with links to both commercial and homebrew 3D scanning gear. The simplest of these methods requires nothing more than a webcam, halogen light source, and a stick!

SIGGRAPH and 3D scanning have been highlighted many times on Hack a Day, but we’re swelling with pride now seeing an academic venue give a favorable nod to the DIY hacking community (on their links page). Okay, so Hack a Day isn’t called out by name, but just wait’ll next year!

[Thanks Fahrzin]

LEGO Mindstorms Sudoku Solver

[youtube=http://www.youtube.com/watch?v=Mp8Y2yjV4fU]

Swedish hacker [Hans Andersson] is no stranger to puzzle-solving robots. His prior work, A Rubik’s cube-solving robot called Tilted Twister, made waves through the internet last year. [Hans’] latest project only has to work in two dimensions, but is no less clever. This new robot, built around the LEGO Mindstorms NXT system, “reads” a printed sudoku page, solves the puzzle, then fills out the solution right on the same page, confidently and in ink. It’s a well-rounded project that brings together an unexpected image scanner, image processing algorithms, and precise motor control, all using standard NXT elements.

The building instructions have not yet been posted, but if the video above and the directions for his prior ’bot are any indication, then we’re in for a treat; he simply has a knack for explaining things concisely and with visual clarity. The source code and the detailed PDF diagrams for Tilted Twister are as gorgeous as his new robot’s penmanship.

[thanks Eric]

Humanoid Robot + Homebrew Waldo = Big Smiles

[youtube=http://www.youtube.com/watch?v=WCTvggKuPvU&feature=player_embedded]

Robot enthusiast [Vitalijus Rodnovas] built this rig to allow a humanoid robot to mimic his own body movements in real time. [Rodonovas] refers to his man-machine interface as a “master-slave suit,” but elsewhere this is often called a waldo after a prescient 1942 [Robert Heinlein] novella. This project page is slight on details and is mostly written in his native Lithuanian, but the pictures speak volumes, and with a little help from Google Translate we can learn the essential facts: The robot itself is a commercially-available kit, the Kondo KHR-1HV from Japan. The custom-built harness uses a collection of surplus Soviet-era military potentiometers (acquired on eBay) to read the positions of his elbows and shoulders, then an ATmega8-based interface board translates these readings into motion commands sent to the robot’s onboard controller. Some additional notes and code can be found on the RoboSavvy Forum.

Does it work? Just watch. His grin as the video progresses is infectious!

Hack a Day has previously covered other Waldos, but this latest deserves style points for its lightweight simplicity.

Maple Beats Up Arduino, Takes Its Shields

maple

The Atmega168 at the heart of every Arduino is an eminently capable chip; its ilk have been seen working as a basic web server, playing back digital audio, even generating TV signals. But as projects continue to grow in sophistication, reality rears its ugly head: Arduino can handle any one of these tasks very well, but it often requires squeezing every last instruction cycle or bit of memory in the device. Even the ’368 chip and the Arduino Mega are stopgap measures. Sooner or later, you have to graduate to long trousers—move up to a more capable microcontroller platform—an uncomfortable change usually involving a hefty investment in new hardware and an intimidating learning curve. Leaf Labs’ Maple aims to change all that…
Continue reading “Maple Beats Up Arduino, Takes Its Shields”

Passive Infrared (PIR) Sensor Tutorial

pirsensor

[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors can be put to other uses—cat flaps, camera triggers and purely artistic applications—as you’ll see in several demo projects and videos. For the curious, the tutorial provides a good amount of background theory on how PIR sensors work, along with the associated fresnel lens optics. And for those who just want to get hacking, most PIR sensors (like the one above) come in a simple-to-interface module containing all the support hardware and providing a simple digital output; the article wraps up with one such example.

Arduino USB Host Shield

UsbHostShield

Circuits@Home has been journaling their development of a USB host mode shield for Arduino, which could bring the platform a veritable explosion of mass storage, keyboard input and countless other peripheral options (and a corresponding raft of new hacks). Currently at the prototype stage, a ready-made shield and library are forthcoming, so keep checking back. Meanwhile, for embedded developers wanting to learn the ropes of USB, the in-progress articles will likely provide some valuable insights.

[thanks Kersny]