Dimanche, Avril 13, 2014 - 13:01Printing In Three Dimensions, For Real This Time
3D printers don’t continuously print in three dimensions – they print one layer, then another, then another. This is true for every single 3D printing technology, but now Topolabs has a very interesting technique that changes that. They’re printing in three dimensions by moving in the Z axis while also printing in the X and Y axes.
The basic idea behind Topolabs’ software is to print a support block, then print an object right on top of the support. The support block can be curved and convex, and the finished product follows the contours of the solid support block. Unlike ‘printing with supports’, the printer extrudes along the X, Y, and Z axes, which should make the finished product much, much stronger.
There are a few drawbacks to the technique – a release agent must be applied to the top of the support block. In the video below, Topolabs is using Kapton, but hair spray or glue sticks will also work. There’s also a limit to how steep an incline a printer can print, determined by the size of the extruder nozzle. Lastly, this technique would be much better suited for a delta-style bot, but the team is getting very good results with a normal Cartesian bot.
You can see a few videos of the Topolabs printing technique below.
Filed under: 3d Printer hacks
Dimanche, Avril 13, 2014 - 10:01The Ultimate Workstation That Folds Up
Looking for an easy way to keep on making stuff even though you’re living in a tiny dorm room? [Matt Silver] was tired of not having a dedicated work-space, so he spent some serious time designing this modular, re-configurable and collapsible portable workstation ready for almost anything.
He started out by sketching ideas, playing around with 3D models in SketchUp, and eventually building a few prototypes using trial and error — and what he’s come up with is pretty darn impressive. It folds down to just under a foot by three feet squared and has casters to roll it around. Once unfolded, you stabilize it by placing your chair on one of the walls that folds down, and the desk itself is also re-configurable for different work surfaces. He’s included a power bar, an LED work-light, and it even has storage racks for tools on the side.
It’s a very thorough Instructable, and definitely worth a look through — especially to see how it magically unfolds! And if you’re wondering about how much it would cost to build, you’re probably looking at around $200 depending on what you already have on hand. What we really like is how it’s almost entirely made out of a single 4′x8′ panel of plywood — it’s like this guy works for IKEA or something!
Dimanche, Avril 13, 2014 - 09:00A Mathematical Proof That The Universe Could Have Formed Spontaneously From Nothing
Cosmologists now have a mathematical proof that natural quantum fluctuations allowed the Big Bang to happen. via medium:
But that still leaves a huge puzzle. What caused the Big Bang itself? For many years, cosmologists have relied on the idea that the universe formed spontaneously, that the Big Bang was the result of quantum fluctuations in which the Universe came into existence from nothing.
That’s plausible, given what we know about quantum mechanics. But physicists really need more — a mathematical proof to give the idea flesh.
Today they get their wish thanks to the work of Dongshan He and buddies at the Wuhan Institute of Physics and Mathematics in China. These guys have come up with the first rigorous proof that the Big Bang could indeed have occurred spontaneously because of quantum fluctuations.
The new proof is based on a special set of solutions to a mathematical entity known as the Wheeler-DeWitt equation. In the first half of the 20th century, cosmologists struggled to combine the two pillars of modern physics— quantum mechanics and general relativity—in a way that reasonably described the universe. As far as they could tell, these theories were entirely at odds with each other.
Dimanche, Avril 13, 2014 - 08:00NASA’s flying saucer to land payloads on other planets
NASA built a flying saucer, which they’ve called the Low-Density Supersonic Decelerator, that will eventually land large payloads on other planets. via Extreme Tech:
No, humble inhabitants of Hawaii, the US government hasn’t increased the level of psychoactive drugs in your water supply: That really is a flying saucer that just flew past your window at three times the speed of sound. Dubbed the Low-Density Supersonic Decelerator, NASA is hoping that this flying saucer is the secret to eventually landing larger payloads on other planets — such as sending a human exploration party to Mars, along with plenty of supplies. The LDSD is on a pretty aggressive schedule, with seven major tech demos over the next 24 months, and could be used in a real mission to Mars in 2018.
Later this year, NASA’s Jet Propulsion Laboratory will use a balloon to launch a test vehicle up to an altitude of 120,000 feet (36.5 kilometers) above Hawaii. The test vehicle will then use a rocket to reach supersonic speeds and raise its altitude yet further to 180,000 feet (54.8 kilometers)… and then it will cut its engine and begin to free fall back to earth. As the capsule passes Mach 3.5 (2,600 mph), the LDSD will kick into action, sprouting a Supersonic Inflatable Aerodynamic Decelerator (SIAD) from the craft and filling it with pressurized air. With the SIAD fully inflated, the spacecraft looks awfully like a flying saucer. The SIAD slows the craft down to around Mach 2, whereupon a massive 30-meter-diameter parachute will then be used to bring speeds down to subsonic landing speeds.
Dimanche, Avril 13, 2014 - 07:01Sewing Conductive Thread in Parallel Lines
[Cynthia] has shared a great video of machine sewing parallel lines of conductive thread onto ribbon using a cording foot which usually comes standard with most machines. This technique could be particularly useful when using addressable LEDs like a NeoPixel to get the ground, data, and positive lined up fairly accurately. Sewing the conductive thread onto ribbon also makes it a hell of a lot easier to attach to many garments or textiles, and also makes it easier to replace or reuse.
The method is pretty easy, essentially using the grooves in the cording foot to guide the conductive treads and ensuring even spacing. Two of the lines are sewn down approximately 3 mm apart using a zigzag stitch. The third line is sewn separately making sure the stitching doesn’t break the first two lines. In the video, a striped ribbon is used which has slight troughs that additionally helps the threads stay in place and the sewer to stay on target.
[Cynthia] of Cynthia Designs Studio has been experimenting with embedding electronics in textiles and has quite a few great videos that you can check out on the Cynthia Designs Studio YouTube channel.
We have seen a machine embroidered LED matrix and a hand sewn LED quilt here on Hackaday, but those who have tried know that conductive thread can be very tricky to work with and keep conductivity. Do you have any tips or tricks for hand or machine sewing conductive thread? If so, please share in the comments below.
Filed under: wearable hacks
Dimanche, Avril 13, 2014 - 07:00Yale Researchers Reconstruct Images of Faces Using fMRI Scans
Led by a Yale University undergraduate, researchers have used fMRI scans to accurately reconstruct the images of faces as seen by the people being scanned. The level of sophistication in fMRI technology has previously allowed researchers to decipher the subject of what a viewer was looking at, such as whether it was scenery versus an animal. But the task of deciphering subtle differences in faces demonstrates a new level of mastery since faces exhibit many more similarities to each other than say, ponies and beach scenes. We also incorporate large areas of our brains to observe all these subtleties, which left much larger areas of the brain to be carefully monitored and greater amounts of brain activity to be decoded. From YaleNews:
Working with funding from the Yale Provost’s office, Cowen and post doctoral researcher Brice Kuhl, now an assistant professor at New York University, showed six subjects 300 different “training” faces while undergoing fMRI scans. They used the data to create a sort of statistical library of how those brains responded to individual faces. They then showed the six subjects new sets of faces while they were undergoing scans. Taking that fMRI data alone, researchers used their statistical library to reconstruct the faces their subjects were viewing.
Cowen said the accuracy of these facial reconstructions will increase with time and he envisions they can be used as a research tool, for instance in studying how autistic children respond to faces.
Dimanche, Avril 13, 2014 - 06:00MIT Creates “Living Material” by Fusing Living Cells with Electronics
Don’t worry, it’s not quite the Borg, but researchers at MIT have managed to combine biology with electronics to produce cells capable of conductivity and light emission. From Dvice:
MIT researchers, led by doctoral candidate Allen Chen, have fused the living and non-living worlds by creating E. coli strands capable of incorporating gold nanoparticles and quantum dots into their colonies. These “living materials” will benefit from both the conductivity and light-emitting properties of their non-living parts and the responsiveness of their bacterial hearts.
The concept is based on naturally-occurring living materials like bone, which incorporates both minerals and living cells. While glowing, conductive bacteria is pretty interesting on its own, the research team believes that its new living circuitry could someday be used in everything from solar cells and diagnostic sensors to self-healing electronics.
Dimanche, Avril 13, 2014 - 06:00Circuit board art
Circuit board art sent in by a reader.
Dimanche, Avril 13, 2014 - 04:00Turn Your Drill Press into a Bobbin/Spindle Sander
Drill presses are a staple tool of the typical garage — they aren’t too expensive and are indispensably useful — but have you ever thought of turning it into a spindle sander?
You can buy drum sander kits fairly cheap, but the problem is they’re really difficult to use and really messy too — you’ll have sawdust everywhere in no time. What [Carl's] done here is created a wood box for his drill press with different size holes for each drum sander bit. By attaching a vacuum cleaner to the box, you can clean up your mess while you’re still doing the work.
Just a note — drill presses aren’t designed to take radial loads like a mill is. If you’re planning on doing some really heavy sanding, adding a bolt through the entire drum sander bit and then coupling it with a fixed bearing inside of your box might be a good idea.
It’s a pretty simple hack, but could save you an additional power tool, and space on your work bench! Have a drill but no drill press? No problem.
Filed under: tool hacks
Dimanche, Avril 13, 2014 - 03:30Maker-Friendly Hardware Stores
Dimanche, Avril 13, 2014 - 01:00A Virtual Cane for the Visually Impaired
[Roman] has created an electronic cane for the visually impaired. Blind and visually impaired people have used canes and walking sticks for centuries. However, it wasn’t until the 1920′s and 1930′s that the white cane came to be synonymous with the blind. [Roman] is attempting to improve on the white cane design by bringing modern electronics to the table. With a mixture of hardware and clever software running on an Android smartphone, [Roman] has created a device that could help a blind person navigate.
The white cane has been replaced with a virtual cane, consisting of a 3D printed black cylinder. The cane is controlled by an ATmega328 running the Arduino bootloader and [Roman's] code. Peeking out from the end of the handle is a Maxbotix ultrasonic distance sensor. Distance information is reported to the user via a piezo buzzer and a vibration motor. An induction coil allows for charging without fumbling for tiny connectors. A Bluetooth module connects the virtual cane to the other half of the system, an Android phone.
[Roman's] Android app runs solely on voice prompts and speech syntheses. Navigation commands such as “Take me to <address>” use the phone’s GPS and Google Maps API to retrieve route information. [Roman's] app then speaks the directions for the user to follow. Help can be summoned by simply stating “Send <contact name> my current location.” In the event that the user drops their virtual cane, “Find my device” will send a Bluetooth command to the cane. Once the command is received, the cane will reveal its position by beeping and vibrating.
We’ve said it before, and we’ll say it again. Using technology to help disabled people is one of the best hacks we can think of. Hackaday alum [Caleb Kraft] has been doing just that with his work at The Controller Project. [Roman] is still actively improving his cane. He’s already won a gold medal at the Niagara Regional Science and Engineering Fair. He’s entered his project in several more science events, including the Canada Wide Science Fair and the Google Science Fair. Good luck [Roman]!
Samedi, Avril 12, 2014 - 22:01Developed on Hackaday: The Top PCB dilemna
The Hackaday community offline password keeper is slowly coming together. A few days ago we received the top PCB for Olivier’s design (shown above). If you look at the picture below, you may see the problem we discovered when opening our package: the soldermask was the wrong color! Given the board is meant to be placed behind a tinted acrylic panel, this was quite a problem…
After using some spray paint, we managed to get to the point shown in the bottom left of the picture. The next task was to find the best way to illuminate the input interface with reverse mount LEDs. Using a CNC mill we machined openings (top right PCB) but also removed some epoxy on both PCB’s sides, thinking it would provide a better light diffusion. We then wrote part of the Mooltipass PWM code and took these pictures:
We hope you agree that the ‘FR4 version’ looks better. The other version, which has the cut openings, illuminates unevenly because the smartcard isn’t under all of the LEDs. This raises several questions that we hope our dear Hackaday readers can answer:
- Can this kind of machining be done in standard PCB fabs?
- Instead of leaving the bare FR4 on top, should we cover it with white soldermask?
- Instead of leaving the bare FR4 on top, should we cover it with white silkscreen?
Keep in mind that we would only need to machine one PCB’s side.
Another concern is the top panel. As previously mentioned we’re currently using a tinted acrylic panel, which may not be the best solution to prevent scratches. We’re thinking to use glass in the future (corning gorilla glass?) so we may also hide everything around the display’s active area. Do you guys have any experience with this? Would it be expensive in relatively small quantities?
As you can see, we still need to find the best compromises and we hope you can help us. Please post a quick message in the comment section below or contact the team in the official Mooltipass Google Group.
Samedi, Avril 12, 2014 - 20:07New Project: Near-Space Balloon Cam with Arduino and APRS Radio
Build this battle-tested rig to launch, track, and recover a high-altitude balloon that will carry your hacked Canon camera to the stratosphere. With this setup using APRS ham radio and the Trackuino — an Arduino-based communications board — any hobbyist or science class can photograph (and video) the Earth against the blackness of space, and bring these amazing images home to share.
Samedi, Avril 12, 2014 - 19:00DIY Linear Actuators For A Flight Sim
[Roland] has already built a few very cool and extremely realistic flight sims, but his latest project will put his current rig to shame. He’s building a six degree of freedom simulator based on homebuilt linear actuators of his own design.
The actuator is powered by a large DC motor moving timing belts along the length of the enclosure. These timing belts are connected to a shaft that’s coupled to the frame with a few bungee cords. The bungee cords are important; without them, the timing belts would be carrying all the load of the sim – not a good thing if these actuators are moving an entire cockpit around a living room.
Also on [Roland]‘s list of awesome stuff he’s building for his flight sims is a vibration system based on the BFF Shaker. This board takes data in from sim software and turns it into vibrations produced by either unbalanced DC motors or one of those ‘bass kicker’ transducers.
It’s all very cool stuff, and with all the crazy upgrades [Roland] is doing to his sim rig, he’s doing much better than paying $300/hour to rent a Beechcraft Baron.
Samedi, Avril 12, 2014 - 18:16Worlds largest multirotor makes successful maiden flight
Advanced Tactics Inc. announced that it has successfully completed the first flight test of the Black Knight Transformer, a modular and roadable vertical takeoff and landing (VTOL) aircraft. Advanced Tactics is at the forefront of large scale multicopter design, production, and testing and the successful flights of the Black Knight Transformer open the door to a number of future aircraft designs that leverage Advanced Tactics’ patented and patent-pending technologies.
The patented AT Transformer technology combines the capabilities of a helicopter, such as the ability to take off and land anywhere, with the capabilities of an off-road automobile. The AT Black Knight Transformer completed driving tests in December 2013 and completed its first flight tests in March 2014. The Black Knight Transformer is the world’s largest multicopter that is controlled and stabilized with propeller speed. The aircraft has a maximum takeoff weight of 4,400 lb.
Samedi, Avril 12, 2014 - 17:00Space Robots, Mars Rovers, and NASA Scientists coming to Maker Faire Bay Area
Samedi, Avril 12, 2014 - 16:48Turn your RROD Xbox 360 into a Bluetooth arcade controller using Adafruit’s Bluefruit EZ-Key – 12 Input Bluetooth HID Keyboard Controller
Dustin Evansfound himself with a few Xbox 360 casings lying around. He ripped all of the remaining hardware out of these boxes and found that what remained was a decent sized box to mount just about anything in. The sturdy design of the 360, which is also just about the perfect shape and size for an arcade controller, seems like an obvious choice when you see it all disassembled like that. With a little bit of measuring to determine spacing that agreed with his hands, and the right parts, Evans was able to make his arcade controller.
Samedi, Avril 12, 2014 - 16:23Transcribing Piano Rolls with Python
Perforated rolls of paper, called piano rolls, are used to input songs into player pianos. The image above was taken from a YouTube video showing a player piano playing a Gershwin tune called Limehouse Nights. There’s no published sheet music for the song, so [Zulko] decided to use Python to transcribe it.
First off the video was downloaded from YouTube. This video was processed with MoviePy library to create a single image plotting the notes. Using a Fourier Transform, the horizontal spacing between notes was found. This allowed the image to be reduced so that one pixel corresponded with one key.
With that done, each column could be assigned to a specific note on the piano. That takes care of the pitches, but the note duration requires more processing. The Fourier Transform is applied again to determine the length of a quarter note. With this known, the notes can be quantized, and a note duration can be applied to each.
Once the duration and notes are known, it’s time to export sheet music. LilyPond, an open source language for music notation, was used. This converts ASCII text into a sheet music PDF. The final result is a playable score of the piece, which you can watch after the break.
Samedi, Avril 12, 2014 - 16:19C’est bientôt Pâques…
Ceux qui me connaissent bien vous le diront, je suis un gourmand :p C’est pourquoi quand Greg a proposé d’organiser un atelier chocolat au sein du log, j’ai saisi l’opportunité
L’objectif de l’atelier : nous apprendre à travailler le chocolat, et réaliser nos propres oeufs en chocolat, et autres « bonbons » fourrés. De mon côté, j’avais déjà assisté à un premier atelier la semaine précédente, pendant lequel j’en avais profité pour faire des sucettes au chocolat en forme de moustaches, fourrées à la ganache chartreuse. Cette fois-ci, je me suis donc concentré sur la réalisation d’un « gros » oeuf
Pour les gourmands qui voudraient s’y essayer, voici un petit récapitulatif de ce qu’il faut (si j’ai bien tout retenu ;)), et de la façon de procéder.
Matériel nécessaire :
- Une grande casserole (pour le bain marie)
- Un petit bol en inox (cul-de-poule)
- Un thermomètre (pas « obligatoire », mais pour débuter, c’est vraiment plus facile )
- Un pinceau
- Un moule demi-oeuf.
- Une spatule métallique
- Pistoles de chocolat (pour moi, c’était du chocolat au lait origine Ghana 40,5%)
- Une bombe d’azote (réfrigérant rapide)
Contrairement à ce qu’on pourrais croire, le moule à œuf n’est pas en silicone, ou autre matériau souple, mais en polycarbonate bien rigide. En effet, le chocolat en refroidissant va se rétracter, et le demi-oeuf se démoulera tout seul.
Première étape : faire fondre le chocolat, au bain marie, en surveillant la température : il faut monter à 40-45° pour le chocolat au lait. Avec un thermomètre c’est facile, sans, ça correspond à un peu moins du seuil de douleur (précis comme indication, n’es-ce pas ;)). Attention à ne pas faire tomber d’eau dans le chocolat lors de cette étape (ni des suivantes), ce qui ferais coaguler ce dernier.
Ensuite, il va falloir tempérer le chocolat. Cette étape est nécessaire à la bonne cristallisation de votre chocolat, et vous permettra d’avoir un joli aspect brillant, exempt de traces blanches. Une fois votre chocolat à température (40-45°C), sortez le du bain marie et ajoutez un peu moins d’un tiers de pistoles à température ambiante (20% de pistoles). Mélangez jusqu’à que tous les pistoles aient fondus. (S »ils disparaissent trop rapidement, rajoutez en un peu)
A l’aide du pinceau, appliquez généreusement du chocolat sur votre moule, en n’hésitant pas à déborder, et en ne laissant aucun trou ou zone transparente. Cette étape assurera un beau fini extérieur et l’absence de bulles en surface. Laissez prendre légèrement, et versez du chocolat fondu (hauteur d’une phalange) dans votre oeuf. Répartissez de manière homogène et laissez reposer un peu. Répétez l’opération encore une fois ou deux, puis videz l’excédent dans le cul-de-poule. Raclez les bords avec une spatule métallique. Mettez au frais.
Au bout de quelques minutes, retirez votre oeuf du frigidaire, et laissez le finir de cristalliser dans un coin assez frais (genre bord de fenêtre à l’ombre). Lorsque vous verrez un petit espace entre le moule et le bord de votre oeuf, il est prêt à être démoulé. Placez vous au dessus d’une surface dure (genre table), mettez la main sur le moule et renversez. S’il tombe tout seul, votre main le retiendra, sinon, tapotez légèrement le moule dur la table (en laissant la main dessous, hein !). S’il ne tombe toujours pas, n’insistez pas, laissez le prendre encore un peu. Attention, ne mettez pas les doigts sur la surface de l’œuf, vous y laisseriez des traces. Prenez le par l’intérieur.
Voilà, c’est démoulé, vous avez un premier demi-oeuf. Vous pouvez répéter l’opération pour avoir l’autre moitié. Faite refondre votre chocolat, et re-tempérez le avant car il a pris pendant ce temps.
Une fois vos deux moitiés d’œuf démoulées, refaite fondre un peu de chocolat et retempérez. Avec le pinceau, appliquez du chocolat sur le bord intérieur de l’œuf, en débordant sur la tranche. Répétez sur l’autre moitié, et assemblez. Vous pouvez maintenant vous servir de la bombe d’azote pour accélérer la prise sur la jonction.
Mon neuneuf à moi :)
ps : pas beaucoup de photos de « pendant », désolé, mais le chocolat, ça en met vraiment de partout
Samedi, Avril 12, 2014 - 14:00Yuri’s Night: The DIY Space Holiday