Hackaday Links: June 19, 2016

Wait a minute. We’re almost through June and we haven’t seen anyone’s ‘DIY air conditioning’ setup. Oh the shame! How could we ever argue about thermodynamics otherwise? Here’s some copper tubing wrapped around a fan. Does it make sense? Assuming you’re making the ice (or cold whatever) in a room separated from the crappy air con, and you don’t have to pay for electricity (or ice), and you don’t mind hauling buckets of ice every few hours, yes. It’ll work. Now we can argue if you should put salt in the ice water…

I know I mentioned this in last week’s links post, but [Arsenijs]’s Raspberry Pi project is growing by leaps and bounds. He already has more than 33 followers to this project (awesome!) and 3.3k views on his project page. Not only is it climbing in popularity, but this is also a great use for the Raspberry Pi. You don’t see projects like this come around very often.

The Goliath is a quadcopter powered by a lawnmower engine. It was an entry in the first Hackaday Prize, but the project literally never got off the ground. There’s now a Mk. II version in the works. Goliath is getting a new frame made out of aluminum tube and rivets. There’s going to be ducts on the props, and this version might actually fly.

You did know Hackaday has it’s own Hackaspace, right? Technically it’s the Supplyframe Design Lab, but there are still a few skull ‘n wrenches hidden in the rafters. The Design Lab is hosting an open house this week on June 23rd, and the design lab residencies will begin July 1st. If you have an idea for something you’d like to build, here’s the residency application.

The LimeSDR is a powerful next generation software defined radio that’s currently on CrowdSupply The crowdfunding campaign ends in just a few days. It’s a very impressive tool, able to send and receive anything from 100 kHz to 3.8 GHz.

Last week one of our writers posted a review on the Monoprice MP Select Mini 3D printer. This printer is becoming stupidly popular, and Monoprice has depleted their inventory twice since then. I’ve been watching the product page for this printer for a while now, and here’s what happens: 1) Printer is out of stock, with an ETA of about a month in the future. 2) Printer is still out of stock, ETA is a few days away. 3) Monoprice has this printer in stock. This cycle seems to repeat every week or so.

Arduino Raycasting. When you think of raycasting, you probably think about Wolfenstein 3D, or other barely 3D games. You don’t need a powerful CPU like a 386 for raycasting – you can do it on an Arduino. The display is a 32×16 matrix of LEDs, control is through a Wii Nunchuck, and yes, head-bobbing is implemented. Here’s a video.

Premier Farnell Sold To Swiss Firm

According to this article in the Guardian, Premier Farnell, the electronics parts distributor who is also a UK manufacturer of the Raspberry Pi, is going to be sold to Dätwyler. Their share price immediately rose 50%, closing at just under the Swiss firm’s offer price.

Farnell itself had been on a binge, according to Wikipedia anyway, buying up electronics distributorships in Poland, India, and the US. In 2009, they bought Cadsoft, the makers of Eagle CAD software. Now they’re being sold to another distributor.

Bloomberg writes this up as being just more consolidation in an already consolidating market. What any of this will mean for the hacker on the street is anyone’s guess, but we’re putting our money on it amounting to nearly nothing. But still, now’s the time to stock up on your genuine UK-owned, made-in-UK Pis before they become Swiss-owned and made who knows where.

Hackaday Prize Entry: Micro Robots For Education

[Joshua Elsdon] and [Thomas Branch] needed a educational hardware platform that would fit into the constrained spaces and budgets of college classes. Because nothing out there that was cheap, simple and capable enough to fit their program, the two teachers for robotics at the Imperial College Robotics Society set out to build their own – and entered the Hackaday Prize with a legion of open source Micro Robots.

These small robots have a base area of 2 cmand a price tag of about £10 (about $14) each, once they are produced in quantities. They feature two onboard stepper motors, an RGB-LED, battery, a line-following sensor, collision-sensors and a bidirectional infrared transmitter for communicating with a master system, the ‘god bot’. The master system is based on a Raspberry Pi with little additional hardware. It multiplexes the IR-communication with all the little robots and simultaneously tracks their position and orientation through a camera, identifying them via their colored onboard LED. The master system also provides a programming interface for the robots, so that no firmware flashing procedure is required for students to get their code running. This is a well-designed, low-cost multi-robot system, and with onboard sensors, stepper motor odometry, and absolute positioning feedback, these little robots can be taught quite a few tricks.

Building tiny robots comes with a lot of regular-sized challenges, and we’re delighted to follow [Joshua Elsdon] and [Thomas Branch] on their journey from assembling the tiny PCBs over experimenting with 3D printing and casting techniques to produce the tiny wheels to the ROS programming. The diligent duo is present in the Hackaday prize twice: With their own Micro Robots project and with their contribution to the previously covered ODrive – an open source BLDC servo controller. We are already curious about their next feat! The below video shows a successful test of the camera feedback integration into the ROS.

The HackadayPrize2016 is Sponsored by:

There’s A Pi In Mike’s Fridge

How often have you stood in the supermarket wondering about the inventory level in the fridge at home? [Mike] asked himself this question one time too often and so he decided to install a webcam in his fridge along with a Raspberry Pi and a light sensor to take a picture every time the fridge is opened — uploading it to a webserver for easy remote access.

Continue reading “There’s A Pi In Mike’s Fridge”

Hackaday Links: June 12, 2016

The Navy is doing some crazy stuff out in China Lake. They were planning to test something out that could potentially make GPS unusable from San Diego to Las Vegas to San Francisco. Those plans were cancelled for ‘internal’ reasons. They will be testing something in Indiana shortly, though. What are they doing? Who knows. That’s what idle speculation in the comments section is for.

3D Hubs, the distributed ‘3D printing service’ thing, now has 30,000 machines distributed around the globe. They also put together the definitive guide to 3D printing recently. For just about everyone reading this, a ‘introduction to 3D printing’ is old news, but this is a very good guide for telling your weird aunt what you’re building in the basement. Forward this one to your family on Facebook.

This one is amazing. Over on Hackaday.io, [Arsenijs] is working on a Raspberry Pi project. It uses a Raspberry Pi, and several accessories and components to make this Raspberry Pi project work. This Raspberry Pi project is already getting far more than the usual number of likes and follows, making this one of the most interesting Raspberry Pi projects in recent memory.

Moog is re-releasing the Minimoog, the original Moog synth from 1970. That’s cool, but what about a DIY Minimoog? That’s what [Scott Rider] is doing with the Crowminius Analog Music Synthesizer on Kickstarter. It’s an analog synth that’s more or less a Minimoog with MIDI, and one of the Kickstarter rewards is a bare PCB.

The future is dancing robots, so here’s a servo-driven Stewart platform that is sure to bring on the robot apocalypse.

What do you do when you need to get your Hackaday fix, but all you have is a laptop from 1995 and a dial-up modem? The Hackaday Retro Edition, of course. That’s a bunch of retro Hackaday posts, posted five at a time, with all the CSS and JavaScript cruft stripped. We’re always interested to see the old machines that are pulling the retro edition down, and [djnikochan] has the latest entry. He found a Thinkpad 380ED from 1997 at the Goodwill store for $15. The RAM was upgraded with a 64MB SIMM, giving this machine a total of 80MB. The Hackaday Retro Edition is viewable with IE 5.5 over a trusty PCMICA WiFi card. Awesome job, and we love to see old iron rendering the retro edition. Send some pics in if you get your old battlestation to load it.

540 LEDs On A Geodesic Sphere

[burgerga] loves attending Music Festivals. He’s also a MechE who loves his LED’s. He figured he needed to put it all together and do something insane, so he build a huge, 15″ geodesic sphere containing 540 WS2812B addressable LED’s. He calls it the SOL CRUSHER. It sips 150W when all LED’s are at full intensity, making it very, very, bright.

As with most WS2812B based projects, this one too is fairly straightforward, electrically. It’s controlled by four Teensy 3.2 boards mounted on Octo WS2811 adapter boards. Four 10,000 mAh 22.2V LiPo batteries provide power, which is routed through a 5V, 30Amp heatsinked DC-DC converter. To protect his LiPo batteries from over discharge, he built four voltage monitoring modules. Each had a TC54 voltage detector and an N-channel MOSFET which switches off the LiPo before its voltage dips below 3V. He bundled in a fuse and an indicator, and put each one in a neat 3D printed enclosure.

The mechanical design is pretty polished. Each of the 180 basic modules is a triangular PCB with three WS2812B’s, filter capacitors, and heavy copper pours for power connections. The PCB’s are assembled in panels of six and five units each, which are then put together in two hemispheres to form the whole sphere. His first round of six prototypes set him back as he made a mistake in the LED footprint. But it still let him check out the assembly and power connections. For mechanical support, he designed an internal skeleton that could be 3D printed. There’s a mounting frame for each of the PCB panels and a two piece central sphere. Fibreglass rods connect the central sphere to each of the PCB panels. This lets the whole assembly be split in to two halves easily.

It took him over six months and lots of cash to complete the project. But the assembly is all done now and electrically tested. Next up, he’s working on software to add animations. He’s received suggestions to add sensors such as microphones and accelerometers via comments on Reddit. If you’d like to help him by contributing animation suggestions, he’s setup a Readme document on Dropbox, and a Submission form. Checkout the SolCrusher website for more information.

Thanks [Vinny Cordeiro], for letting us know about this build.

Continue reading “540 LEDs On A Geodesic Sphere”

The Raspberry Pi Infinity+ Is A Fully Functional Huge Raspberry Pi

It wasn’t an easy weekend for the rest of the world’s hackers and makers, that of the Bay Area Maker Faire. Open your social media accounts, and most of your acquaintances seemed to be there and having a great time, while the rest were doing the same at the Dayton Hamvention. Dreary televised sports just didn’t make up for it.

MCM Electronics had the Maker Faire booth next to that of the Raspberry Pi Foundation, and since they needed both a project to show off and a statement item to draw in the crowds, they came up with the idea of a 10x scale reproduction of a Raspberry Pi above the booth. And since it was Maker Faire this was no mere model; instead it was a fully functional Raspberry Pi with working LEDs and GPIO pins.

The project started with a nearly faithful (We see no Wi-Fi antenna!) reproduction of a Raspberry Pi 3 in Adobe Illustrator. The circuit board was a piece of MDF with a layer of foam board on top of it with paths milled out for wiring and the real Pi which would power the model, hidden under the fake processor. The LEDs were wired into place, then the Illustrator graphics were printed into vinyl which was wrapped onto the board, leaving a very two-dimensional Pi.

The integrated circuits and connectors except for the GPIO pins were made using clever joinery with more foam board, then wrapped in more printed vinyl and attached to the PCB. A Pi camera was concealed above the Broadcom logo on the processor model, to take timelapse pictures of the event. This left one more component to complete, the GPIO pins which had to be functional and connected to the pins on the real Pi concealed in the model. These were made from aluminium rods, which were connected to a bundle of wires with some soldering trickery, before being wired to the Pi via the screw terminals on a Pi EZ-Connect HAT from Alchemy Power.

Is the challenge now on for a range of compatible super-HATs to mate with this new GPIO connector standard?

We previously covered the 2012 Maker Faire exhibit that inspired this huge Pi. The Arduino Grande was as you might well guess, a huge (6x scale) fully functional Arduino. In fact, the world seems rather short of working huge-scale models of single board computers, though we have featured one or two working small-scale computer models.

Thanks [Michael K Castor] and [Christian Moist] for sharing their project with us.