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Hackaday Prize Entry: The Chocometer

จันทร์, 05/25/2015 - 12:00

Diabetes affects almost 400 million people worldwide, and complications due to diabetes – blindness, cardiovascular disease, and kidney problems – can be reduced by regular monitoring of blood glucose. The usual way of measuring blood glucose is with a pin prick of blood and a small test strip that costs about $0.30. That’s a lot of test strips and blood used by 400 million diabetics every day. Wouldn’t it be better if there was a less invasive way of measuring blood glucose?

[marcelclaro]’s project for The Hackaday Prize aims to do just that. Instead of measuring blood directly, his project will measure blood glucose by shining light through a finger or an earlobe. Using light to detect blood glucose is something that has been studied in the lab, but so far, there aren’t any products on the market that use this technique.

There are two major problems [marcel] needs to overcome to turn this project into reality. The first is simply raw data for calibration. For [marcel], this is easy; he has Type 1 diabetes, and takes four glucose measurements a day. Patient heal thyself, or something.

The second problem is getting a photosensor that’s sensitive enough. By using an InGaAs PIN diode, a current-controlled oscillator, and a digital counter, [marcel] should have a sensor that’s good enough, with electronics that are cheap enough, to create some tech that is truly game changing for a few hundred million people around the world.

The 2015 Hackaday Prize is sponsored by:
Filed under: The Hackaday Prize

ESP8266 Keeps An Eye On Your Batteries

จันทร์, 05/25/2015 - 09:00

There are many more things to know about a battery than its voltage and current output at any given moment, and most of them can’t be measured with a standard multimeter unless you also stand there for a long time with an Excel spreadsheet. The most useful information is battery capacity, which can tell you how much time is left until the battery is fully charged or fully discharged. [TJ] set out to create a battery data harvester, and used the ubiquitous ESP8266 to make a fully-featured battery monitor.

Measuring battery capacity is pretty straightforward but it does take time. A battery is first benchmarked to find its ideal capacity, and then future voltage and current readings can be taken and compared to the benchmark test to determine the present capacity of the battery. The ESP8266 is a relatively good choice for this kind of work. Its WiFi connection allows it to report its information to a server which will store the data and make it available for the user to see.

The first page of this project details building the actual module, and the second page outlines how to get that module to communicate with the server. Once you’ve built all of this, you can use it to monitor your whole-house UPS backup system or the battery in your solar-powered truck. There is quite a bit of information available on the project site for recreating the build yourself, and there’s also a video below which shows its operation.


Filed under: wireless hacks

Hackaday Links: May 24, 2015

จันทร์, 05/25/2015 - 06:00

A few months ago, we heard about a random guy finding injection molds for old Commodore computers. He did what the best of us would do and started a Kickstarter to remanufacture these cool old cases. It’s the best story on retrocomputing this year, and someone else figured out they could remanufacture Commodore 64 keycaps. If you got one of these remanufactured cases, give the keycaps a look.

Remember this Android app that will tell you the value of resistors by reading their color code. Another option for the iOS crowd was presented at Maker Faire last weekend. It’s called ResistorVision, and it’s perfect for the colorblind people out there. An Android version of ResistorVision will be released sometime in the near future.

A few folks at Langly Research Center have a very cool job. They built a hybrid electric tilt wing plane with eight motors on the wing and two on the tail. It’s ultimately powered by two 8 hp diesel engines that charge Liion batteries. When it comes to hydrocarbon-powered hovering behemoths, our heart is with Goliath.

A bottom-of-the-line avionics panel for a small private plane costs about $10,000. How do you reduce the cost? Getting rid of FAA certification? Yeah. And by putting a Raspberry Pi in it. It was expoed last month at the Sun ‘N Fun in Florida, and it’s exactly what the pilots out there would expect: a flight system running on a Raspberry Pi. It was installed in a Zenith 750, a 2-seat LSA, registered as an experimental. You can put just about anything in the cabin of one of these, and the FAA is okay with it. If it’ll ever be certified is anyone’s guess.


Filed under: Hackaday Columns, Hackaday links

Handheld Belt Sander Converted To Bench Top Unit

จันทร์, 05/25/2015 - 03:01

Having a basement or garage shop sure comes in useful for the home handyman. One downside to having a self-funded show is that you may not have every tool that you need. [unknownuser2007] had a hand-held belt sander and regularly used it to round off sharp corners on small parts instead of using it for its intended purpose; smoothing out long flat boards. It was typical for [unknownuser2007] to hold the sander in one hand and his work in the other while sanding his wooden parts.

This method of sanding was not very precise (or safe) so he decided it was time to do something about it and build a stand for the sander. The frame is built from 1/2 inch plywood, with pieces jig-sawn to fit the contour of the belt sander housing. After the frame was assembled, a dust collection system was made using an old vacuum attachment and some plastic sheet. The finished rig mounts solidly to the work bench and now allows [unknownuser2007] to use both hands to shape his creations.

As much as we love these types useful tool mods, on revision 2 we’d like to see an easily accessible on/off switch and a work support square to the belt. If you’re interested in more DIY sander solutions, check out this 20 inch disk sander.


Filed under: tool hacks

LayerOne Hardware Hacking Village

จันทร์, 05/25/2015 - 00:00

Go to DEFCON and you’ll stand in line for five hours to get a fancy electronic badge you’ll be showing to your grandchildren some day. Yes, at DEFCON, you buy your hacker cred. LayerOne is not so kind to the technically inept. At LayerOne, you are given a PCB, bag of parts, and are told to earn your hacker cred by soldering tiny QFP and SOT-23 chips by hand. The Hardware Hacking Village at LayerOne was packed with people eagerly assembling their badge, or badges depending on how cool they are.

The badges are designed by [charlie x] of null space labs, one of the many local hackerspaces around the area. The design and construction of these badges were documented on the LayerOne Badge project on hackaday.io, and they’re probably best con badges we’ve ever seen.

There are two badges being distributed around LayerOne. The first is an extremely blinkey badge with a Cypress PSoC4 controlling 22 individually addressable RGB LEDs. Most conference attendees received a bare PCB and a bag of parts – the PCB will get you in the door, but if you want your nerd cred, you’ll have to assemble your own badge.

There are still a few interesting features for this badge, including an ESP8266 module that will listen to UDP packets and drive the LEDs. Yes, a random person on the same WiFi AP can control the LEDs of the entire conference event. The badges can also be chained together with just three wires, but so far no one has done this.

The Speaker and Staff badge, based on a VoCore

The second badge – for speakers and staff – is exceptionally more powerful. It’s a Linux box on a badge with two Ethernet connectors running OpenWRT. For a con badge, it’s incredibly powerful, but this isn’t the most computationally complex badge that has ever been at a LayerOne conference. For last year’s badge, [charlie] put together a badge with an FPGA, SAM7 microcontroller, SD card, and OLED display. They were mining Bitcons on these badges.

The Hardware Hacking Village was loaded up with a dozen or so Metcal soldering irons, binocular microscopes, and enough solder, wick, and flux to allow everyone to solder their badge together. Everyone who attempted it actually completed their badge, and stories of badge hacking competitions at other cons were filled with tales of people sprinkling components on random solder pads. Imagine: a conference where people are technically adept. Amazing.


Filed under: cons

The Ease of Adding Trojans to Major Financial Android Apps

อาทิตย์, 05/24/2015 - 21:01

This was both an amusing and frightening talk. [Sam Bowne] presented How to Trojan Financial Android Apps on Saturday afternoon at the LayerOne Conference. [Sam] calculates that 80-90% of the apps provided by major financial institutions like banks and investment companies are vulnerable and the ease with which trojans can be rolled into them is incredible.

Some Background

[Sam] did a great job of concisely describing the circumstances that make Android particularly vulnerable to the attacks which are the subject of the talk. Android programs are packaged as APK files which are easy to unpack. The “compiled” code itself is called smali and is readable in a similar way as Java. It’s super easy to unpack and search this byte code using grep. Once the interesting parts are located, the smali code can be altered and the entire thing can be repackaged. The app will need to be resigned but Google doesn’t control the signing keys so an attacker can simply generate a new key and use that to sign the app. The user still needs to install the file, but Android allows app installation from webpages, email, etc. so this isn’t a problem for the bad guys either.

The Attack

So what can be done? This is about information harvesting. [Sam’s] proof of concept uses a python script to insert logging for every local variable. The script looks at the start of every module in the smali code, grabs the number of local variables, increments it by one and uses this extra variable to write out the values through logcat.

ADB Log shows the Credit Card Number

He demonstrated live on the Bank of America app. From the user side of things it looks exactly like the official app, because it is the official app. However, when you register your account the log reports the card number as you can see here. Obviously this information could easily be phoned-home using a number of techniques.

As mentioned, the vast majority of banking and financial apps are vulnerable to this, but some have made an attempt to make it more difficult. He found the Bancorp app never exposes this information in local variables so it can’t just be logged out. However, the same trojan technique works as a keylogger since he found the same function kept getting called every time a key is pressed. The same was true of the Capital One app, but it echos out Google’s Android keymap values rather than ascii; easy enough to translate back into readable data though.

The Inability to Report Vulnerabilities

What is the most troubling is that none of these companies have a means of reporting security vulnerabilities. It was amusing to hear [Sam] recount his struggle to report these issues to Charles Schwab. Online contact forms were broken and wouldn’t post data and several publicly posted email addresses bounced email. When he finally got one to accept the email he later discovered another user reporting on a forum that nobody ever answers back on any of the Schwab accounts. He resorted to a trick he has used many times in the past… Tweeting to the CEO of Charles Schwab to start up a direct-message conversation. This itself is a security problem as @SwiftOnSecurity proves by pointing out that whenever @SamBowne Tweets a CEO it’s because he found a vulnerability in that company’s platform and can’t find a reasonable way to contact the company.

There is Hope

Although very rare, sometimes these apps do get patched. The Trade King app was updated after his report and when [Sam] tried the exploit again it crashes at start-up. The log reports a verification failure. This indicates that the injected code is being noticed, but [Sam] wonders if the verification is included in the app itself. If it is, then it will be possible to track it down and disable it.

This may sound like all of us Android users should despair but that’s not the case. Adding verification, even if it’s possible to defeat it, does make the apps safer; attackers may not want to invest the extra time to try to defeat it. Also, there are obsfucators available for a few thousand dollars that will make these attacks much more difficult by making variable names unreadable. The free obsfucator available now with the Android development suites doesn’t change names of everything… local variables are left unaltered and programmers have a habit of using descriptive names for variables. For instance, BofA used “CARDNUM” in the example above.

The Slides

[Sam Bowne’s] slides and testing results for the entire talk are available under the “Upcoming Events” part of his website.


Filed under: Android Hacks, security hacks

Absolute Overkill IKEA Lampan Lamp Hack

อาทิตย์, 05/24/2015 - 18:01

Sometimes too much overkill isn’t enough. [Jesus Echavarria] hacked an IKEA Lampan light for his daughter to add color LEDs, a timer, Bluetooth control over the hue, and a local override knob. The result: a $5 lamp with at least $50 of added awesomeness. Let’s have a look at the latter.

The whole lamp system is based around a PIC microcontroller and WS2811 LEDs for the color light show. Since the lamp was already built to run a 40W lightbulb, and [Jesus] wanted to retain that functionality, he added an SSR to the build. Yeah, it’s rated for 5,000W, but it’s what he had on hand.

Next comes the low-voltage power supply. [Jesus] needed 5V for the PIC, and used the guts from a cheap USB charger as a quick and dirty 5V converter — a nice hack. To power the HC-05 Bluetooth module, which requires 3.3V, he wired up a low-dropout voltage regulator to the 5V line. A level-converter IC (74LVC07) gets the logic voltage levels straight between the two.

A fuse for the high-voltage power line, screw-terminal connectors all around, and a potentiometer for manual override round out the hardware build.

On the software side, [Jesus] set up the knob to turn on and off the built-in lamp as well as control the colors of the LED ring. That’s a nice touch for when his daughter wants to change the lamp’s color, but doesn’t want to go find her cellphone. But when she does, the SPP Pro app sets the colors by sending pre-programmed serial commands over Bluetooth to the PIC in the lamp.

All in all, a nice build, well-documented, and with enough rough edges that none of you out there can say it’s not a hack. Nice job [Jesus]! We can’t wait to see what he does next… robot lamp anyone?


Filed under: home hacks, led hacks

Spin DIY Photography Turntable System

อาทิตย์, 05/24/2015 - 15:01

A motorised turntable is very handy when taking product pictures, or creating animated GIF’s or walk around views. [Tiffany Tseng] built Spin, a DIY photography turntable system for capturing how DIY Projects come together over time. It is designed to help people share their projects in an engaging way through creating GIF’s and videos which will be easy to post on social networks like Twitter and Facebook.

The device is a lazy susan driven by a stepper motor controlled via an Arduino and an Easy Driver motor driver shield. The Spin system utilizes the Soft Modem library to send signals from an iPhone to the Arduino. This connects the Arduino to the iPhone via the audio socket on the phone. The Spin iOS app is currently in Beta and is invite only. After you’ve built your own Spin turntable, take a picture of it and request the app. Of course, there are many different ways of controlling the motor so if you are handy, you can build your own controller. But [Tiffany]’s iOS app provides a way to stitch the various images to form an animated GIF and then share them easily. Building the turntable should be straightforward if you grab the design files from the github repo, follow the detailed instructions on the build page, and have access to a laser cutter and a 3D printer.

Check out a few similar turntable hacks we’ve featured in the past, such as one that uses the motor from a scanner, an attempt that just didn’t end up working smoothly, and one that uses a belt-drive system. There’s a video of the turntable in action after the break.


Filed under: digital cameras hacks

Hackaday Prize Entry: Arduino MPPT Controller

อาทิตย์, 05/24/2015 - 12:00

Imagine you’re building a small solar installation. The naive solution would be grabbing a solar panel from Horror Freight, getting a car battery and AC inverter, and hoping everything works. This is the dumb solution. To get the most out of a solar you need to match the voltage of the solar cell to the voltage of the battery. How do you do that? With [Debasish]’s entry for The Hackaday Prize, an Arduino MPPT Solar Charge Controller.

This Maximum Power Point Tracker uses a buck converter to step down the voltage from the solar cell to the voltage of the battery. It’s extremely efficient and every proper solar installation will need a charge controller that does something similar.

For his MPPT, [Debasish] is using an Arduino Nano for all the math, a DC to DC buck converter, and a few MOSFETs. Extremely simple, but [Debasish] is connecting the entire controller to the Internet with an ESP8266 module. It’s a great example of building something for much less than it would cost to buy the same thing, and a great example for something that has a chance at making the world a little better.

 

The 2015 Hackaday Prize is sponsored by:
Filed under: The Hackaday Prize

NES Controller Made Out Of Fused Craft Beads

อาทิตย์, 05/24/2015 - 09:01

Close your eyes and think back, far back when you were a wee kid. Remember those colored beads that a child would populate on a small plastic peg board, arranged in some sort of artsy pattern, then ironed to fuse the beads together into a crafty trinket? They were fun for kids but what good are they to us adults nowadays? Well, [Lalya] has shown that they can be used to make a unique and interesting NES Controller.

First, the controller’s front panel was laid out on the pegboard, remembering to lay it out in reverse so the melted side of the beads was facing into the controller. Holes were left in the top panel for the D-pad and B/A buttons. The sides, back and bottom panels of the controller were made the same way. Hot glue holds the case panels together.

Inside the case is an Arduino and breadboard with three through-hole momentary buttons. These are wired up to the Arduino inputs and a sketch emulates keystrokes when connected to a computer. Unfortunately, the D-pad’s functionality is just a button right now. [Lalya] uses the project to control iTunes.  Maybe the next revision will be more video game friendly.

Having your own NES controller recreation might not be high on your list. But you have to admit that this s a pretty simple and inexpensive way to make custom enclosures.


Filed under: toy hacks

3D Scanning Rig And DIY Turntable

อาทิตย์, 05/24/2015 - 06:00

It seems almost every day 3D scanning is becoming more and more accessible to the general DIYer. The hardware required is minimal and there are several scanning softwares and workflows to choose from. However, if you have slowly walked around a subject while holding a Kinect and trying to get a good scan, you know this is not an easy task. A quick internet search will result in several DIY scanning setup solutions that have been cobbled together and lack substantial documentation…. until now! [aldricnegrier] is fighting back and has designed and documented a rotary table that will spin at a constant speed while a subject is 3D scanned, making person scanning just that much easier.

The project starts off with a plywood base with a Lazy Susan bearing assembly attached to the top. The Lazy Susan supports the rotating platform for the subject person to stand on, but it’s not just a platform, it’s also a huge gear! The platform teeth mesh with a much smaller 3D printed gear mounted on the shaft of a DC motor and reduction gearbox assembly.

Another goal of the project was to make the rotary table autonomous. There is an ultrasonic sensor mounted to the base aimed above the rotating platform. The ultrasonic sensor is connected to an Arduino and if the system senses someone or something on the platform for 3 seconds, the Arduino will command a DC motor driver to start spinning the platform.

As cool as this project is so far, [aldricnegrier] wanted to make it even cooler: he added speech recognition. Using Microsoft’s Speech Toolkit, saying the words ‘Start Skanect‘ will start the scanning process on the PC. Now, a sole person can scan themselves easily and reliably.

[aldricnegrier] has made all of his CAD files, STL files and Arduino code available so anyone wanting to build this clearly capable setup can do so!


Filed under: 3d Printer hacks

Pictures that Defeat Key Locks

อาทิตย์, 05/24/2015 - 03:01

We’re at LayerOne this weekend and one of the talks we were excited about didn’t disappoint. [Jos Weyers] presented Showing Keys in Public — What Could Possibly Go Wrong? The premise is that pictures of keys, in most cases, are as good as the keys themselves. And that pictures of keys keep getting published.

[Jos] spoke a bit about new services that offer things like 3D scanning and storage of your key for printing when you get locked out, or apps that ask you to take a picture of your key and they’ll mail you a duplicate. Obviously this isn’t the best of ideas; you’re giving away your passwords. And finding a locksmith is easier than findind a 3D printer. But it’s the media gaffs with important keys that intrigues us.

We’ve already seen the proof of concept for taking covert images to perfectly duplicate a key. But these examples are not so covert. One example is a police officer carrying around handcuff keys on a belt clip. Pose for a picture and that key design is now available to all. But news stories about compromised keys are the biggest offenders.

A master key for the NYC Subway was compromised and available for sale. The news coverage not only shows a picture at the top of the story of a man holding up the key straight on, but this image of it on a subway map which can be used to determine scale. This key, which is still published openly on the news story linked above, opens 468 doors to the subway system and these are more than just the ones that get you onto the platform for free. We were unable to determine if these locks have been changed, but the sheer number of them has us thinking that it’s unlikely.

Worse, was the availability of fire-department master keys which open lock boxes outside of every building. A locksmith used to cut the original keys went out of business and sold off all their stock. These keys were being sold for $150, which is bad enough. But the news coverage showed each key on a white background, straight on, with annotations of where each type of key will work.

Other examples include video news stories about credit card skimmers installed in gas pumps — that coverage showed the key used to open the pump housing. There was also an example of speed camera control cabinet keys being shown by a reporter.

[Jos’] example of doing the right thing is to use a “prop” key for news stories. Here he is posing with a key after the talk. Unfortunately this is my own house key, but I’m the one taking pictures and I have blurred the teeth for my own security. However, I was shocked during image editing at the quality of the outline in the image — taken at 6000×4000 with no intent to make something that would serve as a source for a copy. It still came out remarkably clear.

Some locks are stronger than others, but they’re all meaningless if we’re giving away the keys.


Filed under: lockpicking hacks

Hacklet 48 – Weather Sensing Projects

อาทิตย์, 05/24/2015 - 00:01

Throughout history, mankind has been at the mercy of the weather. Planning a major outdoor event like a wedding or a naval battle? Better hope for clear skies! Man doesn’t have the ability to change mother nature at will quite yet, but hackers are working on it! Until then, we can measure  the current conditions and predict the weather in the near future. A bit of help from cloud based computer models and global sensing even allows us to model and predict weather patterns days in advance. It’s no surprise that makers, engineers, and hackers love weather projects. We’ve found there are two basic project groups (with a some overlap between them): Sensing projects and display projects. This week’s hacklet focuses on some of the best weather sensing projects on Hackaday.io!

We start with [diysciborg] and Modular Weather Station. This 2014 Hackaday Prize entrant is a DIY outdoor weather station. [diysciborg] went with easily available PVC pipe and sheet metal for most of his mechanical build. His anemometer alone is a work of art. Mounting 8 magnetic reed switches in slots cut in a PCB allows for a thin device which can easily sense the speed of the wind. Other sensors include a TLS230R light to frequency converter for sunlight measurement, CO, wind direction, and more. An Arduino Pro Mini is at the center of it all.

[Clovis Fritzen] is saving the planet from global warming with his project FacilTempo. FacilTempo is a weather station, and an entry in the 2015 Hackaday Prize. The idea is to make a simple and low-cost setup which can be built in bulk and placed anywhere on the Earth. [Clovis] plans to measure temperature, humidity, atmospheric pressure, sunlight, and rain. He also hopes to add a Sparkfun sensor to monitor wind speed and direction. All the data will be transmitted via a radio link. [Clovis] is adding the ability for FacilTemp to communicate via 433 MHz, WiFi, or Bluetooth. The entire sensor suite and its on-board ATmega328 will be powered by a LiPo battery. The battery will be charged by solar or wind power, depending upon what is available on site. With 8 project logs already in the can, FacilTempo is well on its way to beating back global warming!

[Ulf Winberg] is building the Low Cost Weather Station, his entry in the 2015 Hackaday Prize. Low Cost Weather Station aims to be a $50 sensor suite for local weather conditions. [Ulf] plans to power the entire device using wind and solar energy. He’s hoping to avoid batteries by storing his power in a supercapacitor. Power calculations have been taking up quite a bit of his design time so far. The $50 bill of materials limit is one that [Ulf] is serious about. He’s keeping careful eye on his component selections to keep that goal attainable. The system will transmit wind speed, wind direction, sun, and other data through a Laird BL600 Bluetooth low energy transceiver.

Finally we have [Greg Miller] taking it back to basics with Weather Station Zeta. Zeta is [Greg’s] first big project. He’s only just recently learned to solder, but he’s already squeezing a lot of performance out of a little Arduino. The idea is to create a two station system. The outdoor station will monitor the weather, including temperature, humidity, and barometric pressure. Data will be transmitted to an indoor station with a similar set of sensors. The indoor station will also include a 20 line x 4 column character LCD to display the data.  [Greg] has the indoor section of the system just about done, and he’s working on learning the ins and outs of XBee data radios. He’s also going to include an Adafriut CC3000 breakout board to Web enable the weather station. We love seeing ambitious early projects like this one!

If you want to see more projects like these, check the Weather Sensing Projects list on Hackaday.io. 

That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!


Filed under: Hackaday Columns

Finally, VR For Four Eyes

เสาร์, 05/23/2015 - 21:00

In the next few years, VR headsets will be everywhere, and everyone will slowly recede into their own little reality that is presented on high-resolution displays right in front of their eyes. One specific group will be left out: eyeglass wearers. VR just doesn’t work with eyeglasses, and a few people in Germany are fixing this problem. They’re creating custom prescription lenses for Google Cardboard, giving anyone with glasses the opportunity to look just a little more hipster.

The folks behind this Indiegogo already run a specialty optics shop in Germany. They have the tools to make custom lenses for spectacles, and they’re the first company so far that has identified a problem with the current crop of VR headsets and has created a solution. The campaign is for a set of lenses that can be attached to Google Cardboard with double stick tape. There are limitations on how strong of a prescription they can make, but it should work for most four eyes.

It should be noted this Indiegogo isn’t the only way to get custom lenses for a VR headset. If you have your prescription, there are a few places to buy glasses online for $30 or so. Do that, remove the lenses from the frame, and affix them to Cardboard.


Filed under: Crowd Funding, Virtual Reality

From Broken Drill Bit To Knife: Backyard Forging Basics

เสาร์, 05/23/2015 - 18:00

One of our tipsters sent in a great video showing how to make knives out of old broken drill bits. It comes from [The Art of Weapons] YouTube channel which is run by a 15 year old from the UK. He’s applying old techniques to modern technology and it’s awesome to see someone young with these skills.

The beauty of this hack is aside from the tools you’ll need, it’s practically free to do. Worn out drill bit or other steel tool? No problem – heat it up and make something new. At the heart of this build is making your own forge. There’s lot of options, from using firebricks, to making a soup can forge like he did. From there, it’s really just a matter of annealing the steel (heating it up to red hot, and letting it cool down slowly in sand), and then heating it up again and forming it with a hammer and anvil.

But he doesn’t stop there: he also shows us his method of making handles for knives out of hardwood — its a pretty cool process and the finished knives are beautiful. The video below is a bit long, but well worth the watch if you’re interested in trying your own hand at forging.

[Thanks Ag!]


Filed under: weapons hacks

Hackaday Fail: A $3000 Prototype That Doesn’t Work

เสาร์, 05/23/2015 - 15:00

[Dan Royer] is hard at work building his own personal robot army. Robots mean motors, and motors mean gearboxes. In [Dan]’s case, gearboxes mean $3000 wasted on a prototype that doesn’t work. Why doesn’t it work? He doesn’t know, and we don’t either.

[Dan] would like to use small but fast DC motors for his robots coupled to a gearbox to step down the speed and increase the torque. The most common way of doing this is with a planetary gear set, but there’s a problem with the design of planetary gears – there is inherent backlash and play between the gears. This makes programming challenging, and the robot imprecise.

A much better way to gear down a small DC motor is a hypocycloid gear. If you’ve ever seen the inside of a Wankel engine, this sort of gearing will look very familiar: a single gear is placed slightly off-axis inside a ring gear. On paper, it works. In reality, not so much.

[Dan] spent $3000 on a prototype hypocycloid gearbox that doesn’t turn without binding or jamming. The gear was made with incredible tolerances and top quality machining, but [Dan] has a very expensive paper weight sitting on his desk right now.

If anyone out there has ever designed or machined a hypocycloid gearbox that works, your input is needed. The brightest minds [Dan] met at the Bring A Hack event at Maker Faire last weekend could only come up with. ‘add more lasers’, but we know there’s a genius machinist out there that knows exactly how to make this work.

Hackaday Fail is a column which runs every now and again. Help keep the fun rolling by writing about your past failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.


Filed under: Fail of the Week

Hackaday Prize Entry: Biopotential Signal Library

เสาร์, 05/23/2015 - 12:00

With prosthetics, EEG, and all the other builds focused on the body and medicine for this year’s Hackaday Prize, it might be a good idea to take a look at what it takes to measure the tiny electrical signals that come from the human body. Measuring brain waves or heartbeats indoors is hard; AC power frequencies easily couple to the high impedance inputs for these measurements, and the signals themselves are very, very weak. For his entry to The Hackaday Prize, [Paul Stoffregen] is building the tools to make EEG, ECG, and EMG measurements easy with cheap tools.

If the name [Stoffregen] sounds familiar, it’s because he’s the guy behind the Teensy family of microcontroller boards and several dozen extremely popular libraries for everything from displays to real time clocks. The biopotential signal library continues in [Paul]’s tradition of building very cool stuff with just code.

The hardware used in this project is TI’s ADS1294, a 24-bit ADC with either 4 or 8 channels. This chip is marketed as a medical analog front end with a little bit of ECG thrown in for good measure. [Paul] is only using the ADS1294 initially; more analog chips can be added later. It’s a great project in its own right, and when you include the potential applications of this library – everything from prosthetics to body sensors – it makes for an awesome Hackaday Prize entry.

The 2015 Hackaday Prize is sponsored by:
Filed under: Medical hacks, The Hackaday Prize

Commodore 64 Mods Make A Mobile Computer

เสาร์, 05/23/2015 - 09:01

Some Commodore C64 owners and enthusiasts keep tinkering with their precious units, adding upgrades all the time. [wpqrek]’s latest upgrade to his C64 makes it totally portable – he added DC-DC converters to allow it to run off external battery sources.

He installed two separate DC-DC converters – one for 5V and another for 9V inside the enclosure. He opted for these high-efficiency converters because he planned to use batteries to power the device and wanted to maximize the juice he was extracting. He wired up a barrel jack socket to accept a 12V input, and another XT60 socket where he could attach a LiPo battery. A common 2200mAh RC battery is enough to power his C64 for 1.5 hours. To ensure the LiPo battery doesn’t get fully discharged, he’s added a simple buzzer circuit that starts beeping at around 3.3V.

How does just adding an external battery help make it portable? Well, he’s already added a small LCD display and a couple of other mods, that we featured in an earlier post. These earlier mod’s didn’t make the unit truly portable. Adding the latest hack does. Check out the video after the break.


Filed under: computer hacks

Forbidden Fruit Machine

เสาร์, 05/23/2015 - 06:00

Here’s another example of how today’s rapid-prototyping technologies are allowing Artists and Craftsmen to create interactive works of art rapidly and easily. [Kati Hyypa] and [Niklas Roy] teamed up to transform a classic painting in to an interactive exhibit. It’s a painting of Adam, Eve and the apple with a joystick attached. Spectators can control the destiny of the apple with the joystick and thus explore the painting.

The “Forbidden Fruit Machine” is based on a painting called “The Fall of Man” created by [Cornelis Cornelisz van Haarlem] in 1592. The painting depicts Eve and Adam in the Garden of Eden, being tempted by the serpent to eat the forbidden fruit. A public domain, high-resolution scan of the painting is available for download from the Rijksmuseum Amsterdam. Starting with that, the arms were edited out, and replaced with articulated versions (mounted on acrylic) driven by servos. The apple was mounted on a X-Y gantry driven by two stepper motors. These are driven by a motor shield, which is controlled by an Arduino Uno. The Uno also controls a Music Maker shield to play the various audio tracks and sound effects. Finally, an additional Arduino Pro-Mini is used to control the LED lighting effects via a Darlington driver and also connect to the end stops for the X-Y gantry. The joystick is connected to the analog ports of the Uno.

The LED’s give clues on where to move the apple using the joystick, and pressing the red button plays an appropriate audio or sound effect. For example, pressing the button over the cat at Eve and Adam’s feet elicits a heart-breaking meow, while letting Eve eat the apple results in an even more dramatic effect including a thunder storm.

The machine is open source with code posted on Github and 3d files on Youmagine. Watch a video after the break. The artist’s names may be familiar to some some readers – that’s because both have had their earlier work featured on our blog, for example this awesome ball sucking machine and another one too.

 


Filed under: misc hacks

Arduino vs Arduino: These Are Not The Droids…

เสาร์, 05/23/2015 - 03:01

We’ve been trying to not pick favorites in the Arduino controversy, or at least remain open-minded to both sides of the story. Some businesses, on the other hand, are clearly aligning themselves.  (Full text of e-mail below.)

Reader [Francisco Zabala], from cool robot-supplies store Acrobotic, got this e-mail from an Amazon distributor where he purchased some Arduinos “ages ago” and was angered enough at the brazen tone to drop us a line.

Thank you for our Arduino purchase from our Amazon.com store. We truly appreciate your business.

We are writing to let you know about an important change in Arduino products. The new website for Arduino is now officially Arduino.org. The old website (arduino.cc) should no longer be used.

All new Arduino hardware will be transitioned from the old Arduino.cc badging to the new Arduino.org badging. Please be aware that during this transition, you may receive Arduino hardware with either Arduino.cc or Arduino.org. Both are authentic Arduino-brand hardware.

If you use Arduino.org branded hardware on the old site, you may be presented with an error. Please use the new Arduino.org site.

We know for sure that Arduino SRL sent out a letter to distributors claiming that they were the real Arduino because they’ve been manufacturing the boards. Seeing a distributor recommend against the software at arduino.cc in such stark terms makes us wonder if there have been similar letters sent out concerning the IDE fork. Anyone have anything? Send us a tip if you do.

We find it a little ironic that when arduino.cc added the now-retracted popup that specifically targeted boards made by Smart Projects / Arduino SRL,  that they opened themselves up to this sort of counter-attack: if you see an error popup, just switch over to the “new official” IDE. Oops. Good that it’s gone now.

Finally, we’ve got to say that “the old website should no longer be used” is pretty rich: we’re hackers, we use whatever software / IDE we like, thank you very much! No matter how the legal battles end up, and no matter who tells you to use what codebase, the beauty of open source is that it’s up to you, and not them. Hack on, y’all!

Thanks, [Francisco] for the tip.


Filed under: Arduino Hacks, news