Tuesday, February 11, 2014 - 10:01TARDIS Alarm Doesn’t Go VWORRRRRP VWRORRRP VWORRRP
Motion sensors are pretty useful — but they’re just so darn ugly! Well — if you’re a Whovian — maybe this hack is for you. A 3D printed TARDIS Motion Sensor Alarm!
[Malcolm] has a home security system that uses a series of motion sensors to detect movement in the house. When movement is detected an indicator LED turns on, and a wireless signal is sent to the main control system. So after discovering a nice 3D model of the TARDIS (Time and Relative Dimension in Space) on Thingiverse, he decided to see if he could hack one of his motion sensors to fit inside of it instead.
As it turns out, it was as simple as removing the sensor’s external shell, 3D printing a few support pieces inside of the TARDIS, and soldering on a bright blue LED to replace the dinky indicator light. Simple, but effective!
Don’t forget to check out the following video. Allons-y!
Sadly, it doesn’t go vworrrrp. Fun fact though, the groaning, wheezy sound the TARDIS makes was originally achieved by dragging a house key down the bass strings of an upright piano. There was a bit of post-processing, but apparently the essence of it is still used today!
Tuesday, February 11, 2014 - 07:00Introducing the SquareWear Mini, with its Chainable Color LED Matrix
[Ray] just tipped us about his latest project: the SquareWear Mini, which basically is an improved version of the SquareWear 2.0 that we featured a month ago. For our readers that may have missed it, the SquareWear is essentially a wearable Arduino platform running at 3.3V and 12MHz. Both versions are based on an ATMega328 microcontroller running the V-USB library to provide USB connectivity, put together with diverse onboard peripherals.
As you can see in the picture above, the Mini includes 2 N-MOSFETs, one temperature sensor, one light sensor, a 16KB EEPROM memory, one buzzer, a one cell LiPo battery connector together with one charging controller, and finally a power switch (USB/battery). It is supposed to be 25% smaller than the SquareWear 2.0 and is optimized to work with a WS2812B-based 5×7 RGB LED matrix that [Ray] also designed. The latter can easily be cascaded in X/Y directions with other LED matrices in order to expand the overall display.
At last, [Ray] created a software to design animations and upload them to the SquareWear . A presentation video of the complete system is embedded after the break and you can download all the design files on GitHub.
Tuesday, February 11, 2014 - 04:01Cobalt RaQ Retrofit Help Geek Up Your Entertainment Center
Even network engineers who toil away in hot server rooms (which aren’t actually all that hot because they’re well climate controlled) deserve nice things. That’s why Cobalt came out with these gorgeous front bezels for their rack mounted equipment… around twenty years ago. [Geekmansworld] is reviving the look, but he’s not hiding it away in a server rack. He scrapped the guts and used the front bezel and controls as part of his media server.
His first new addition to the case was a pair of hard drives which connect to an eSATA hub also stored in the enclosure. He buttoned it up and gave it a test run. Everything worked smoothly and he hopes that it will continue that way without overheating when the summer rolls around again.
Of course a dead front bezel is no fun so he cut off the portion of the original circuit board which hosts the buttons seen on the right. These buttons now connect to a U-HID board which turns the button presses into mouse or keyboard inputs using a USB connection. The original display was swapped out for a backlit character LCD. The LEDs to the left are a refit which turns the status indicators into a VU-Meter. See the entire thing at work after the break.
Filed under: home entertainment hacks
Tuesday, February 11, 2014 - 01:00Python With Braces
If there’s one thing about Python that’s slightly disconcerting, it’s the complete lack of braces, or as they’re called in American English, suspenders. A feature of every variety of C, Java, PHP, Perl, and a whole bunch of other very powerful languages, braces make things more legible and don’t rely on precise indentation. [Ruby] and [Eran] have come up with a way to use these punctuation marks with Python in a project they call Python with Braces.
As its name implies, Python with Braces doesn’t care about indentation: you’re free to make you code extremely ugly, or write your code properly in K&R style. Each line is terminated in a semicolon, and blocks of code with only one statement don’t require curly braces, just like C and Java.
Right now [Ruby] and [Eran] have a Windows installer with an OS X package on its way. Executing a Python with Braces script only requires executing it with a ‘pythonb’ executable instead of the normal ‘python’ executable.
Filed under: Software Development
Monday, February 10, 2014 - 22:01Java Grinder Spits Out dsPIC and MSP430 Assembly Code
[Michael Kohn] sent in a link to the set of projects he’s been working on lately. The Java Grinder is a project that converts Java code for use on microcontrollers. This actually started back in 2009, when he mentioned that the project was worthless because there were already a ton of Java virtual machines out there. But if he had really thought that he’d never learn anything. We’re glad [Michael] picked this back up and made something out of it.
The image above shows the proof of concept. It’s a box bouncing around the Nokia 6100 screen. He wrote the animation in Java, and used his grinder to turn the code into dsPIC assembly, which was then compiled and flashed onto the microcontroller. That’s not all, he’s also coded a Mandelbrot set generator or the same hardware. As it stands he can also produce assembly code for use on MSP430 chips.
This kind of exploration is great for the brain. We see it as a natural extension of the learning you acquire from Nand2Tetris which walks through the essential text The Elements of Computing Systems. If you’re not familiar, that’s a trip from building your first logic gate, which you plunk together with others to build an ALU, then start coding all the way up to a virtual machine to run on your simulated hardware.
Video of the bouncing box and Mandelbrot set is below.
Filed under: Microcontrollers
Monday, February 10, 2014 - 19:00Controlling Motors Without A Microcontroller
Think you need a microcontroller or a proper motor driver to control a motor? Not really. Because RS-232 serial ports are a hack in and of themselves, you can control two motors with only a serial port and a bridge driver.
Instead of using the data pins on the serial port, this circuit works on with the DTR and RTS control signals of an RS-232 interface. Unlike the data lines of a serial port, these control signals are high when they’re enabled and can also provide a small amount of current – enough to control a pair of pins on a TA7291P bridge driver.
The rest of the circuit consists of a few resistors and a pair of motors, and the software simply turns the DTR and RTS lines on and off. It’s enough for a small robot to waddle across a table, and given the correct driver is simple enough to mash together out of parts from a junk drawer.
Filed under: robots hacks
Monday, February 10, 2014 - 16:00The Two Component Random Number Generator
[Karl] was in need of a hardware random number generator, but is needs had a few caveats: it needed to be cheap, and sufficiently random. Random number generation can get quite crazy with Geiger tubes, lava lamps, and radioactive decay, but a much smaller solution was found in an 8 pin AVR microcontroller.
The solution uses AVRentropy, a library that uses the watchdog timer’s jitter in AVR microcontrollers to provide cryptographically secure random numbers. Setting up the circuit was easy – an ATtiny45 microcontroller was connected to a cheap chinese USB to serial converter. Three wires, and the circuit is complete. The code was simple as well; it’s just a call to initialize the entropy and write the bits to the serial port.
There are a few drawbacks to this build. Because the entropy library must wait until enough entropy is gathered, it can only produce about two 32-bit numbers per second. That’s all [Karl] needed for his application, though, and with an enclosure made from a wine cork and marble, he has the prettiest and smallest random number generator around.
Filed under: ATtiny Hacks
Monday, February 10, 2014 - 13:00Wow. Such Mining Rig. So Amaze.
After hearing about cryptocurrencies like Bitcoin, Litecoin, and Dogecoin, [Eric] decided he would have a go at designing his own mining rig. The goals of the project were to have a self-contained and stackable mining rig that had all the parts easily accessible. The result is this awesome computer enclosure, where GPU mining and traditional woodworking collide.
For mining all those coins, [Eric] is using five R9 280x GPUs. That’s an impressive amount of processing power that ended up being too much for the 1500W power supply he initially planned to use. With a few tweaks, though, he’s managing about 2.8 Mh/s out of his rig, earning him enough dogecoins to take him to the moon.
In the video below, you can see [Eric] building his rig out of 4×8 framing lumber. This isn’t a slipshod enclosure; [Eric] built this thing correctly by running the boards through a jointer, doing proper box joints with this screw and gear-based jig, and other proper woodworking techniques we don’t usually see.
Filed under: computer hacks
Monday, February 10, 2014 - 10:017-Foot DIY Wind Turbine Proves Size Matters
When [brokengun] decided to build a 7 ft diameter wind turbine, he had no idea how to even start, so he did as most of us would do and read some books on the topic. His design criteria was that it would be simple to construct and use as many recycled parts as possible. This wind turbine charges a 12 volt battery which can then be used to power a variety of gadgets.
Although made from recycled components, this isn’t a thrown together wind turbine. A lot of thought went into the design and build. [brokengun] discusses matching the blade size to that of the generator in order to maximize power and efficiency. The design also incorporates a feature that will turn the turbine perpendicular to the wind if the wind-speed gets to high. Doing this prevents the turbine from being damaged by strong gusts.
For the main support/hub assembly, a Volvo 340 strut was used because they are widely available, cheap and known for being long-lasting. The tail boom is made from electrical conduit and it’s length is determined by the size of the main fan rotor. The tail vane is made from steel sheet metal and its surface area is also dependent on the fan rotor size to ensure that the turbine functions properly. The blades are made from wood but instead of making them himself, [brokengun] felt these were worth ponying up some cash. [brokengun] also scored a 30 ft high lattice tower an airport was getting rid of. This worked out great as it’s just the right height for a turbine of this size.
Monday, February 10, 2014 - 07:00Hack a Mag-Lite to be Rechargeable
Most tools sport rechargeable batteries these days, but there’s no need to toss that old flashlight: just replace the cells with rechargable ones!
[monjnoux] had a 3-cell D-sized MagLite lying around—though you could reproduce this hack with a 2 to 5 cell model—which he emptied of its regular batteries and replaced with some 11000mAh NiMHs from eBay. The original bulb was also tossed in favor of a 140-lumens LED.
After disassembling the flashlight, [monjnoux] set about installing the new parts. He replaced the original bulb with the LED, soldering it into place and securing it with hot glue. He then drilled a hole in the body of the flashlight for a DC socket. The charger he purchased is adaptive, detecting the number of cells and adjusting its voltage accordingly. It had the wrong connector, though, so [monjnoux] simply chopped off the end and soldered on a new one. For a hack that comes in at 40€, it’s definitely a cheaper alternative to the official rechargeable model: which costs 80€. And with a duration of 7 hours (though it’s unclear whether this number reflects continuous use), it likely outlasts the official model, as well.
Filed under: tool hacks
Monday, February 10, 2014 - 04:00Single Digit Numitron Clock
The above may look like a Nixie tube, but it’s a Numitron: the Nixie’s lower-voltage friend, and part of [pinomelean's] single-digit Numitron clock. If you’re unfamiliar with Numitrons, we suggest you take a look at our post from a few years ago, which includes a helpful tutorial to catch you up to speed.
[pinomelean] built this little device to capture a steampunk-ish look on the cheap for a clock small enough to fit on a wrist. The build uses a PIC16F84A uC and a 4MHz crystal on a custom PCB. A small button on the side lets the wearer set the time. Similar to the Vibrating Timepiece from last month, the Numitron clock isn’t perfect, though it is more accurate: gaining only one minute every 3 days.
Check out the video after the break to see it being set and keeping track of the time. It may take a moment to understand how to read the clock, though. Each of the four LEDs indicates where the number in the Numitron tube belongs. The LEDs light in sequence from left to right, displaying the clock one digit at a time.
Monday, February 10, 2014 - 01:01Hackaday Links: February 9, 2014
Here’s a quick tip to extend the usefulness of your multimeter. It’s a set of mini test hooks soldered to alligator clips with a short hunk of stranded wire in between. You can buy mini test hooks that go right on the metal probes of your meter, but the weight and bulk of the meter probes and cords sometimes get in the way. This rig allows more flexibility because of that wire.
Staying on the theme of test equipment tips, here’s a simple way to make a Y-connector for logic analyzers. [Thomas] uses a dual-row pin header, shorting each pair of pins so that both rows are connected. When this is plugged into a pin socket it leave two pins for connecting your test equipment and the rest of the project hardware.
If you’re going to be in Anaheim this week you can stop by the ATX-West expo and see a 3D printer with a 1m x 1m x 0.5m printing area. [Thanks Martin]
Speaking of 3D printers, here’s a big delta robot (seven feet tall) outfitted for alternative material printing. It’s printing a CT scan of ribs and a heart in hot glue. This seems to be a popular material for more artistic uses. We just saw a hexapod which deposits hot glue as it roams.
The weaponized quadcopter post from Tuesday was a controversial one. The really bad part of it was the laser, which strapped to anything is extremely dangerous. But the other hack may have just been poorly executed. Hackaday alum [Jeremy Cook] wrote in to mention that fireworks and quadcopters can be used more responsibly. He strapped a sparkler to his quadro and used it to make light graffiti. You may remember that [Jeremy] wrote an introduction to light graffiti for us back in November.
Sunday, February 9, 2014 - 22:01Hack All the Things in the Time You Save with This LED Pomodoro Timer
Do you want to use your time more productively but are tomato-averse? [Robin]‘s LED Pomodoro timer could be the perfect hack for you.
The Pomodoro Technique is a time management solution developed in the late 1980s. The basic idea is to spend a very focused 25 minutes performing some activity such as working or studying and then take a 5-minute break. Many of its proponents use a tomato-shaped kitchen timer to alert them to switch between the two states, but [Robin] wanted to make his own and learn along the way.
First, he wanted to use an ATtiny85 and learn about its features. Specifically, he used its timers, PWM, and low-power sleep mode. [Robin] used Charlieplexing to drive a total of six LEDs. When the timer starts, five yellow LEDs are driven high to indicate each 5-minute slice of work time. A red LED is lit during the 5-minute break.
[Robin] also explored compact PCB design and fabrication. All components are SMD and his board is 4cm square. [Robin] is using this SMD buzzer for discrete feedback. He included a footprint for a six-pin ISP header and programmed it with pogo pins. The timer is completely interrupt-driven: one click of the tactile button starts the work counter, and the buzzer sounds when time is up. A second click starts the break counter.
[Robin] has made everything available in his GitHub repo and encourages you to use it. Time’s a-wastin’!
Sunday, February 9, 2014 - 19:00Mario Doorbell Guaranteed To Drive A-You A-Crazy
Is your doorbell not exciting enough for your guests? [Joe] wanted to provide a little entertainment for his visitors, so he redesigned his doorbell with a Mario theme.
Whenever someone presses the button—which carries the Mario coin image—the segment display increments and the Mario coin sound plays. To add variety, the life-up sound plays at every 10 coins and the mushroom upgrade sound plays upon reaching 100. [Joe] tried putting the life-up sound at its appropriate 100′s place and the mushroom sound at every 10, but he decided the brevity of life-up was more tolerable in the 10′s slot.
The project was divided into two components. The door button has a PIC16F628A microcontroller with a dual 7-segment LED display, a button, and a homemade circuit board. All this lives in a simple box covered by a Yoshi’s Island-themed decal. The button’s board connects to a separate ringer board—based around a PIC16F87—with a MCP4822 DAC and a 25LC1024 EEPROM. Button presses on the first board prompt a request for a sound clip read on the EEPROM. Keep clicking for a demo video below.
Filed under: Microcontrollers
Sunday, February 9, 2014 - 16:00Driving RGB Pixel LEDs With CAT5 Cable
[Teknynja] was working on a project where he needed to drive a few strips of Adafruit Neopixels – WS2812 LED strips – that were located several feet apart. These LED strips draw a lot of current, and are very timing sensitive; anything more than a few feet of wire between the microcontroller and the LED strip will probably result in missed data, voltage drops, dimming LEDs, and possibly a non-functional strip.
The solution, as in all matters concerning long distance transmission of data, was CAT5 cable. [Teknynja] used RS-422 drivers and receivers to pull this task off, with 75174 line drivers receiving signals from a Teensy 3.0, and 75176 bus transceivers reading everything at the other end of a 20 foot cable.
For the power drop issue, [Teknynja] is feeding 12V into a few of the wire pairs in the cable and using a cheap LM2596 buck converter to step everything down to 5V at the strip.
With a fairly simple circuit, [Teknynja] was able to drive a few strips of WS2812 LEDs through 20-foot lengths of CAT5 cable with ease; it worked just the same as if the pixels were connected directly to the Teensy on a workbench.
Filed under: led hacks
Sunday, February 9, 2014 - 13:00Using A Computer To Read Braille
[Matthiew] needed to create a system that would allow a computer to read braille. An electromechanical system would be annoying to develop and would require many hardware iterations as the system [Matthew] is developing evolves. Instead, he came up with a much better solution using a webcam and OpenCV that still gets 100% accuracy.
Instead of using a camera to look for raised or lowered pins in this mechanical braille display, [Matthiew] is using OpenCV to detect the shadows. This requires calibrating the camera to the correct angle, or in OpenCV terms, pose.
After looking at the OpenCV tutorials, [Matthiew] found a demo that undistorts an image of a chess board. Using this same technique, he used fiducials from the ARTag project to correctly calibrate an image of his mechanical braille pins.
As for why [Matthiew] went through all the trouble to get a computer to read braille – something that doesn’t make a whole lot of sense if you think about it – he’s building a braille eBook reader, something that just screams awesome mechanical design. We’d be interested in seeing some more info on that project as well.
Sunday, February 9, 2014 - 10:00Upgrading Home Automation to Home Anticipation
[Bithead's] already built some home automation to control the lighting and temperature in his house while he’s away, but he wanted to take things a step further and have the house automatically anticipate his arrival and adjust the environment accordingly. The project takes advantage of geofencing to create a perimeter around the home that listens for a transceiver in [Bithead's] car. We featured a similar project with a Raspi a few months ago, which locked the doors upon driving away.
[Bithead's] implementation uses a pair of Digi Xbee Pro XSC radios with U.FL antennas to provide an impressive 2+ mile range of communication. The home-based Xbee hooks up to a Parallax Xbee USB adapter and subsequently into his computer—its antenna sits in a nearby window on the top floor of his house to maximize range. For his car, [Bithead] originally opted for an Xbee shield and an Arduino Uno, but he’s recently overhauled the build in favor of an Arduino Fio, which reduced the footprint and increased the range. Check out his page for the build log specifics and more pictures.
Sunday, February 9, 2014 - 07:00Adding an RPM Readout for a Home Made CNC Mill
[Rui] recently put the finishing touches on his homemade CNC mill, which utilizes a dremel-like rotary tool. The problem with using rotary tools for this kind of application is you don’t really have an accurate speed readout… so he designed his own RPM gauge.
The sensor is in itself very simple. He’s using a TLE4935L hall effect sensor, a spare 16FE88 microcontroller, a Nokia LCD, and one tiny neodymium magnet. The magnet has been carefully epoxied onto the motor fan, with the hall effect sensor close by. He’s also built a guard around it, just in case the magnet decides to fly off at high speeds.
During testing he hooked up the hall effect sensor to both his home-made circuit, and an oscilloscope to confirm his findings. Once he was assured everything was working properly he sealed it off and mounted the LCD above the spindle as a nice digital readout.
Filed under: cnc hacks