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September 23, 2016

Turn a Raspberry Pi Zero Into a Miniature Dongle Computer

Filed under: Uncategorized — ketan @ 6:49 PM

The Raspberry Pi Zero’s best feature is its size, but that comes at the cost of ports. DIYer Node figured out how to turn the Pi Zero into a dongle computer so it can tether itself directly to another computer’s network through USB, making it much easier to use.

With a few mods, Node turns the Zero into a dongle computer, which means you simply need to plug it into your computer and it’ll start sharing the network resources. From there, you can SSH or VNC into the Zero and control it using your laptop or desktop computer, no extra mouse, screen, or keyboard required. This is great for setting up different SD cards or testing projects when you don’t want to pull out a bucnh of extra gear. Head over to YouTube for the full guide.

Turn The Raspberry Pi Zero Into a Mini Dongle Computer | Node

from Lifehacker

September 22, 2016

5 More SuperCon Speakers You Don’t Want to Miss

Filed under: Uncategorized — ketan @ 7:39 AM

5 More SuperCon Speakers You Don’t Want to Miss

This morning it is my pleasure to announce five more confirmed speakers for the Hackaday SuperConference. The ultimate hardware conference takes place in just a few weeks: November 5th and 6th in Pasadena, California.

Get your tickets now!


  • Avidan Ross is the Founding Partner of Root Ventures. Before founding the firm in 2013, he designed industrial robotics for the Food Network’s kitchens, was the CTO of CIM Group where he invested in industrial Internet, and worked as an embedded network application developer at Excite@Home. Away from work, Avidan spends time cooking, glassblowing, and working on his new book about coffee around the world. He has a Bachelor’s degree in Computer Science from Columbia University where he focused on networking protocols.
  • Sam Bobrowicz moved to Pullman, WA from the Seattle Tacoma area. He studied computational neuroscience at Washington State University, before getting transfixed with the power of FPGAs and coming to work for Digilent. Today he is the Applications Manager at Digilent and specializes in Xilinx Zynq development. In his free time, he enjoys skateboarding and backpacking. Convinced that anyone can learn and use FPGA technology, Sam continues to produce and create content that helps users get on boarded to this segment of the technology field.
  • Akiba is based out of Japan and active in the international hardware hacker community. He specializes in product design and manufacturing and teaches what is involved with navigating the factory ecosystem of Shenzhen. When not in Shenzhen, he’s spending time at Hackerfarm, a hackerspace he and some friends founded in rural Japan specializing in agricultural and environmental technology. He runs his own company, FreakLabs, is a research affiliate with MIT Media Lab, and has also been a design consultant to the UN, International Atomic Energy Agency, Google, and various other organizations.
  • Matt Berggren is a hardware engineer, programmer, and product developer. He has extensive experience in designing for FPGA and embedded systems, having spent part of his career with Altium before becoming Senior Director of Product at Supplyframe. Matt is now applying his wide experience as Director of Autodesk Circuits, Eagle, and Tinkercad.
  • Sprite_TM, aka Jeroen Domburg, has always been interested in anything that goes on in the place where hardware meets software. He is an incredibly skilled hardware hacker, able to reverse engineer circuits and code quickly and despite almost any level of obfuscation. He shares this incredible work on his well-known website: In 2015 Sprite joined Espressif — creators of the ESP8266 — to develop high performing wireless chips at low cost; he is the Software Engineering Manager leading the team behind the recently release ESP32 chip. Sprite has a reputation for incredible hardware talks. It’s well worth your time to check out his 2015 Hackaday SuperCon talk. Sprite_TM has made equally amazing presentations at the 2014 Hackaday Prize gathering and many other conferences.

These speakers join the five we announced last week: Christal Gordon, Ben Krasnow, Luz Rivas, Ken Shirriff, and Alan Yates. This list of ten confirmed speakers is far from complete. We still have about twenty additional presenters and workshops to announce. More on that soon — including talk titles and descriptions — once we have worked through all of the proposals and confirmed with the invited presenters.

So much goes into developing a product. From the first glimmer of an idea, to a rough prototype on the bench, working with manufacturers (or turning your shop into the assembly line), and working through the firmware and software that will support the equipment. SuperCon is the place to come together with a huge range of people whose collective knowledge and experience covers it all. If you love hardware, you can’t miss this.

It may be too early to know who all the speakers are, but it’s not too early to get your ticket. They will sell out, don’t pass up these Early Bird Tickets.

Find more SuperCon posters and flyers on the event page.

from Hack a Day

Arduino Sketch: The Next Generation

Filed under: Uncategorized — ketan @ 7:34 AM

What was your first Arduino program? Probably an LED blinker — that seems to be the “hello world” of microcontrolllers. You probably moved on to things a little more complicated pretty quickly. At some point, things get harder because the Arduino lacks an operating system.

There are operating systems that will run on the Arduino. They aren’t full-featured like Windows or Linux, but they allow you to run multiple tasks that are both isolated from each other (to some degree) and have a way to cooperate (that is, synchronize, share data and resources, and so on). One such operating system is ChibiOS. It will run on AVR- and ARM-based devices. You can find documentation about the entire project on the home page along with other ports.

The problem with adopting a new operating system is always getting started. [ItKindaWorks] has started a video series on using ChibiOS and has posted three installments so far (see below; one is about getting started, the other two cover messaging, mutexes, and priorities).

If you want to follow along with the videos, the code is available on GitHub. We aren’t sure if he’s planning more videos, but these will be more than enough to get you started.

According to the ChibiOS project, they are better than many common similar operating systems because of their static design (you can put the processor to sleep without causing problems). They also support true threads instead of simple tasks, meaning that you can dynamically create and destroy threads and synchronize threads easily.

If you are building sophisticated software that needs multiple things occurring at once, having an operating system can make life a lot easier. We’ve seen examples of using ChibiOS ranging from motor control to MIDI players. There are quite a few choices other than ChibiOS, too, if you look around.

from Hack a Day

September 17, 2016

Wanhao Duplicator i3 Should Put an End to “Cheapest Printer” Kickstarters

Filed under: Uncategorized — ketan @ 5:36 PM

Is the Wanhao Duplicator the best printer on the market? Not at all. Is it a contender for best low-price printer?Definitely. If you consider it a low priced kit printer instead of a finished product then it’s possible that, in its price class, it is hands down the best out there.

For somewhere between 300 and 500 dollars, the Duplicator is a hell of a printer. Also selling under the name Cocoon and Maker Select, the printer is a thin folded sheet steel frame clone of the Prusa i3. I opened the box expecting the most flagrant cost cutting I could imagine. I figured the steel would be paper thin. The holes wouldn’t line up. I expected the connections to be improperly terminated. I expected a fire.

The Duplicator six screws away from being fully assembled. When the manual says find a 1m x 1m flat area to work in it's not kidding. This table was too small.
The Duplicator six screws away from being fully assembled. When the manual says find a 1m x 1m flat area to work in it’s not kidding. This table was too small.

What I got was up and printing in under an hour. What I got was something designed by someone who cares, but with an obvious cost goal. As a bonus, it even printed pretty well. As mentioned, the basic shape of the frame is that of a Prusa i3. A horizontal bit holds the bed and y movement. A vertical bit is attached to the middle of that, making a T. It holds the X, Z, and nozzle.

My previous experience with the MK10 can be carachterized with the nickname I gave the 2X. An all metal cold-end replacement helped the situation considerably.

My previous experience with the MK10 can be characterized with the nickname I gave the 2X. An all metal cold-end replacement helped the situation considerably.

An example of the duplicator's construction. Note the welded on gussets. Lots of nice small details like these.

An example of the duplicator’s construction. Note the welded on gussets. Lots of nice small details like these.

The extruder and hotend is a clone of the MK10 extruder, an advancement on the stolen IP hodpodge popularized by Makerbot before Makerbot got smart and ruined everything. So far, despite warnings that it’s the first to go, the extruder has performed admirably for me with mid quality Chinese PLA filament.  It’s eaten one roll and is working on another without a single jam, which is farther than the 3,000 dollar Replicator 2X got before jamming for the first time.

I am not certain whether anything but PLA is advisable out of this nozzle, but it’s been printing successfully between 200 and 220C. I would recommend, as always, not purchasing the cheapest filament one can find. Especially black filament. If longevity and print quality is your goal spend money to get better quality stuff.

The linear mechanics of the printer are good, but of a questionable parentage. This printer is really quiet. The component I questioned the most are the rods, but they seemed to be straight and precise enough, if not precision.

So we meet again my old nemesis.
So we meet again my old nemesis.

The linear bearings were the standard LM8UU bearings we’ve all come to know and love. All of them were pressed into solid aluminum pillow blocks and, presumably then, properly preloaded. This means that the bearings can be gently shifted lower down the list of likely suspects if you need to start chasing accuracy problems. The diameter of the rods or the odd way they’re mounted to the frame would be better culprits.

The Z axis travels on two ACME thread leadscrews and brass lead nuts. Really, the Z on this printer was pretty dang good, though I did have an eerily familiar wobbliness that lead me to believe there were alignment issues that needed to be carefully resolved if a better quality print is desired. The other option being that one of the screws is bent, but it seemed unlikely. Unfortunately my time with the printer was less than two months so I didn’t get a chance to figure it out. Also, it looked to be a huge unrewarding job. The entire Z assembly is dauntingly inaccessible when it comes to taking it apart. Though Wanhao did include all the tools to do it. If you want to service it, be prepared to disassemble it completely.

The X and Y are the standard belt arrangements we’ve come to expect. Both were of a serviceable construction. I was pretty impressed to see welded gussets for stiffening some of the brackets. They wouldn’t necessarily be required on a printer of this price point, but to me they were a clear indication that the designers of the printers cared. However, the X belt did rub against one of the pillow blocks. Many people complained about this to Wanhao. I personally noticed zero performance issues because of this. Regardless, Wanhao ended up fixing the problem in newer printers by replacing one of the pillow blocks with a snap-fit plastic piece. This is a little disappointing mechanically, but still shows a laudable responsiveness to the community.

Threaded rod and linear bearings.
Threaded rod and linear bearings. Complex sheet metal parts.

The frame it’s all mounted in is almost entirely made of bent and painted sheet metal. Overall the bending job is well done and the parts show a good degree of finishing work. When it came time to align screw holes to their mating feature there was very little flexing of the frame needed to bring it all into final alignment. On that subject too, every tapped hole threaded perfectly. I was also impressed by the small number of screws required for each task. I still remember having to remove dozens of unnecessary screws to do even simple routine work on the Makerbot Replicator 2X.

Despite being metal, the frame does flex a bit. I wouldn’t go as far as to say that it’s stiffer than the threaded rod and 3mm sheet steel construction of the original Prusa, but it’s certainly stiffer than anything made of wood or acrylic. There is a simple 3D printable mod for the printer available on Thingiverse though. It completes the triangle between the base and the vertical piece and dramatically stiffens the whole construction for noticeably better prints. Especially when printing fast.

The full bed assembly sandwich. With residue of an extremely hard to remove tape.
The full bed assembly sandwich. With residue of an extremely hard to remove tape.

The bed is an aluminum PCB with a sheet of BuildTak like material on it. This part worked flawlessly and I had zero issues with it. However, the sub plate to which the four leveling screws and springs attach was woefully thin. It was sheet of die cut sheet aluminum. It was really frustrating to level the print bed. If it required any force at all to remove the part, the bottom plate bent slightly, requiring that the whole process be redone.

If I could make one definite change to this printer, it would be focused at the bed mounting plate and leveling screws. Ideally the plate would be of a lighter and stiffer material and the screws would be replaced with auto bed leveling.

The electronics are predictably cheap, but no worse than what many of the more expensive kits are packaging. It is currently running a modified Melzi board, designed to be as cheap as possible for mass manufacture. It has a custom firmware, which considering the things that can happen if failsafes are removed, should probably be replaced with vanilla Marlin or Repetier immediately.

The electronics were nicely done.
The electronics were nicely done.

Even though the first iterations of the Wanhao duplicator had serious connection problems, this one was very well done. The connectors were all the inexpensive, but quality JST type. The crimps are properly done, the wires labeled. The workmanship is not bad. There were some odd things, like electrical tape for holding a connector together rather than hot glue or, the even more expensive option, buying a connector with a positive lock.

There were definitely some design compromises for purely price reasons as far as the wiring went too. The right z-motor, y-axis endstop, and x-axis motor had no loom or any kind of protection at all. Another length of cable chain or even spiral loom may have pushed the budget too far. The cable itself should last, but care should be taken not to pull it out when moving the machine.

The inside of the massive driver enclosure was nice too. There were lots of nice touches like color coded connectors, EMI shielding, and proper isolation on the AC input. The power supply is a knock-off meanwell, but they seem to do well in the community. It’s worth noting that the massive electronics box does NOT detach from the main printer. It was likely done this way so a different factory or section of their factory could do the final assembly, testing, etc. on the electronics. However, it’s very clunky and it’s very possible to break a connection if you’re not careful when moving the printer.

The build in spool holder works well. It's a nice feature. Weirdly, the plastic piece was turned on a lathe, not molded..
The built in spool holder works well. It’s a nice feature. Weirdly, the plastic piece was turned on a lathe, not molded.


The more I worked with the Duplicator the more impressed I was by the company. Yes, the Duplicator is cheap. The components are cheap. The frame is cheap. It’s cheap all the way down to its bones. The company still delivers. It works. It’s quiet. It’s well-enough designed.

It is a complete printer out of the box, but I feel like when compared to the higher end complete printers it rates as low as its price in the rankings. However, if you don’t compare this printer to the complete assemblies — if you consider it a kit and don’t mind spending another two to three hundred bucks on it — it’s entirely possible to convert this printer to one that’s as good as any of the higher end printers. The community around these printers is amazing. A stronger bed, frame stiffening, auto bed leveling, a more reliable extruder, careful alignment, and a firmware upgrade is all that’s standing between this printer and it’s more expensive competitors.

On top of that, my impression of Wanhao is a good one. They don’t have the best support in the world, but if you want better support… pay more for your hardware. They do seem to listen to the complaints though as the improvements vanish in each iteration. Their newest printer got rid of the aggravating micro SD card, the strange external electronics box, and more.  They are proving themselves to be quite the competitor and the premium 3D printer makers need to drastically up their game or they’ll find themselves having a hard time justifying their higher costs not to far in the future from now. We regularly see new Kickstarter campaigns that try to market themselves as the cheapest 3D printer. This one actually sidesteps the snake oil and delivers a printer that works at a price that most would consider “low”.

It was a love hard won. The Duplicator did spend the first two weeks on the floor. Just in case it felt like catching fire.
It wasn’t love at first sight. There were trust issues. The Duplicator did spend the first two weeks on the floor. Just in case it felt like catching fire.

from Hack a Day

Open Hardware RC Radios

Filed under: Uncategorized — ketan @ 5:15 PM

A decade ago, RC transmitters were clunky, expensive and PCM. A decade before that, everything was analog. Now, RC transmitters are completely digital, allowing for hundreds of aircraft to take to the sky. They’re also cheap, thanks to engineers in China. Now, they’re open hardware, too.

An old Futaba radio outfitted with AR Uni electronics. Image source: vikar
An old Futaba radio outfitted with AR Uni electronics. Image source: vikar

An exceptionally long thread over on the RCGroups forums has been going on for a few months, extolling the virtues of the ‘AR Uni’ board that turns old transmitters into full featured digital radios. This board runs everything, from two analog sticks, a directional keyboard, pots galore, switches everywhere, and a fancy LCD that makes programming easy. The joys of Open Hardware, brought to RC geeks. It’s a thing of beauty.

Like the Turnigy 9x radio, this barebones radio module uses RF modules — backpacks that contain the radio. This is also Open Hardware, and it’s compatible with just about every radio protocol out there. It’ll talk to everything from a Hubsan quadcopter to a Spektrum DSM2 receiver, and it’s simple enough that it can be built on stripboard.

When it comes to Open Hardware, the effort shown in these two projects cannot be overstated, even though the authors and creators of these projects seem to ignore their place in the context of the last decade of Open Hardware. Combine these projects with a few of the quadcopter flight computers and receivers, and you have a completely open hardware flying machine.

from Hack a Day

Smartphone TV Remote Courtesy of Homekit and ESP8266

Filed under: Uncategorized — ketan @ 5:07 PM

Smartphone TV Remote Courtesy of Homekit and ESP8266

Good grief, this smartphone-to-TV remote really drives home how simple hardware projects have become in the last decade. We’re talking about a voltage regulator, IR LED, and ESP8266 to add TV control on your home network. The hardware part of the hack is a homemade two sided board that mates an ESP with a micro-USB port, a voltage regulator to step down fom 5 to 3.3 v, and an IR LED for transmitting TV codes.

Let’s sit back and recount our good fortunes that make this possible. USB is a standard and now is found on the back of most televisions — power source solved. Cheap WiFi-enabled microcontroller — check. Ubiquitous smartphones and established protocols to communicate with other devices on the network — absolutely. It’s an incredible time to be a hacker.

Television infrared remote codes are fairly well documented and easy to sniff using tools like Arduino — in fact the ESP IR firmware for this is built on [Ken Shirriff’s] Arduino IR library. The rest of the sketch makes it a barebones device on the LAN, waiting for a connection that sends “tvon” or “tvoff”. In this case it’s a Raspberry Pi acting as the Homekit server, but any number of protocols could be used for the same (MQTT anyone?).

from Hack a Day

September 15, 2016

B&O Play speakers get Google Cast multiroom support

Filed under: Uncategorized — ketan @ 2:43 PM

In its battle to cover consumers’ homes with connected speakers, B&O recently began outfitting its gear with Google Cast functionality. Operating like a Chromecast does on your TV, the company’s speakers can directly pull music from the streaming service you’re using instead of either your smartphone or tablet. That’s on top of its existing AirPlay, DNLA and Bluetooth support. After initially allowing owners to Cast their music to individual speakers, B&O confirmed today that the technology has been opened up to work seamlessly with the other B&O speakers in their multiroom setup.

While Sonos is seen as the go-to brand for multiroom speakers, Google Cast has slowly gained the support of other popular speaker makers. Harmon Kardon, Vizio and Philips are all utilizing the standard, giving Google’s streaming technology a much needed boost. Sonos, on the other hand, has gone the other way, opening up to support control directly through Spotify and the Amazon Echo. B&O says both the Beoplay A6 and second-generation Beoplay A9 are already compatible, while its soundbar and other networked speakers will gain multiroom support via a software update.

from Engadget

September 6, 2016

T³: Hot Wheels Speed Trap

Filed under: Uncategorized — ketan @ 9:03 PM

Adding a chronograph to Hot Wheels track to measure the speed of passing toy cars.




At the ISTE 2016 conference, one educator told me that he planned to make a timer for Hot Wheels tracks using an Arduino with his class (I apologize, as I do not remember who it was! If you are reading this, please leave a comment so I can give you full credit).

I thought it was a really great classroom project idea, so I wanted to share. Instead of a timer, I constructed a chronograph using the SparkFun Inventor’s Kit and an extra photocell. Here’s a video showing the project in action:

I would be remiss if I did not post full instructions for building the project. Good news, everyone! They can be found on InventorSpace.

CChronograph for Hot Wheels

Click the photo to see how to make your own Speed Trap

I was honestly surprised to find that Hot Wheels still makes track sets. The particular one I used in the video can be found at Target.

What other nostalgic toys would you want to hack?

from SparkFun Blog

September 3, 2016

SQL Server Access Control: The Basics

Filed under: Uncategorized — ketan @ 7:19 PM

No technology yet invented can in any way allow us to neglect the task of ensuring the security of the database by controlling access. Security must be applied in depth, and the database is designed provide a system that will thwart even the most determined external attack. If it seems a bit complicated at first, that is no longer an excuse now that Rob Sheldon has provided this simple guide for getting started.

from SQLServerCentral

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