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We Have A Problem: 3D Printers Are Too Expensive

อังคาร, 06/09/2015 - 18:01

Hackaday, we have a problem. 3D printing is changing the world but it’s still too expensive to be embraced as a truly transformative technology.

With each passing year, the 3D printing industry grows by leaps and bounds. Food safe PLA is now the norm, with dissolvable and other exotic filaments becoming more mainstream.  New filaments are making it possible to print objects that were not possible before. New CAD software is popping up like dandelions, with each iteration giving novice users a friendly and more intuitive interface to design 3D models. As time marches on, and we look into its future, a vision of the 3D printing world is evident – its only going to get bigger.

Imagine a future where a 3D printer is as common as an ink jet printer in homes all across the world.  A future where you could buy filament from the supermarket down the street, and pick up a new printer from any hardware store. A future where dishwashers, refrigerators and bicycles come with .stl files that allow you to print upgrades or spare parts. A future where companies compete to give the market easy-to-use printers at the cheapest price.

Is this future possible? Not until the technology changes. It’s too expensive, and that’s the problem you’re going to solve. How can you make a 3D printer cheaper? A cheap printer could change the game and make our future a reality.

Where do we need cost savings?

To get you going, here are some parts of common 3D Printers which think need to find cost-saving solutions.

XYZ AND HOT END MOTORS

Stepper motors are going to run you about $15 each. Is it possible to use cheaper DC motors with some type of position tracking while keeping the cost down?

HARDWARE

Threaded rod is probably the cheapest way to move your XYZ axis. What about couplings and guide rods? Check out how this guy made a CNC out of parts from his local hardware store.

ELECTRONICS

No arduino with Easysteppers here – too expensive. We’ve just seen a super cheap controller a few days ago. If we use something other than NEMA steppers, it will radically change the typical electronic controller for our super cheap 3d printer.

EXTRUDER

What is the cheapest way to melt and extrude plastic? What about using thermistors in place of thermocouples? Let’s think out of the box with this, and see if we can get away from the typical stepper motor based extruder. Remember, everything is low cost. If we have to sacrifice some resolution, that is OK.

So there you go. Let’s hear your input on the issue. We need to make 3D printers a lot more affordable and we want to hear any ideas you have on the topic in the comments below. Do you think this is in our future and why?

The 2015 Hackaday Prize is sponsored by:
Filed under: 3d Printer hacks, Hackaday Columns, The Hackaday Prize

Bringing a Century Stereo into the 21st Century

อังคาร, 06/09/2015 - 15:01

Way back in the previous century, people used to use magnetized strips of tape to play music. It might be hard to believe in today’s digital world, but these “cassette” tapes were once all the rage. [Steve] aka [pinter75] recently found a Bang & Olufsen stereo with this exact type of antequated audio playback device, and decided to upgrade it with something a little more modern.

Once the unit arrived from eBay and got an electronic tune-up, [pinter75] grabbed a Galaxy S3 out of his parts drawer and got to work installing it in the old cassette deck location. He used a laser cutter to make a faceplate for the phone so it could be easily installed (and removed if he decides to put the tape deck back in the future).

The next step was wiring up power and soldering the audio output directly to the AUX pins on the stereo. Once everything was buttoned up [pinter75] found that everything worked perfectly, and mounted the stereo prominently on his wall. It’s always great when equipment like this is upgraded and repaired rather than thrown out.


Filed under: musical hacks

Hackaday Prize Entry: Useful Code For Useful Things

อังคาร, 06/09/2015 - 12:00

The Hackaday Prize isn’t exclusively about building things that will help the planet; you can also build things that will enable others to build things to save the planet. [Eric] isn’t saving the world with his commonCode library, but it will make it vastly easier for other people to build the next great Thing.

The idea behind commonCode is the same as shared libraries you’ll find in any desktop application of reasonable size; it provides a common library for AVR microcontrollers to build just about anything. Bit manipulation, an interface for timers, math functions, graphics, I/O, and peripheral drivers are all available in the commonCode library. This makes it easy for the developmentally challenged among us to create whatever project they want.

The commonCode library wasn’t created just for The Hackaday Prize. [Eric] has been tinkering around with AVRs since well before the Arduino existed, and he has dozens of projects in permanent installations. It’s a great way to give back to the community, and the perfect way to allow people to develop their own things to solve whatever problem they have in mind.

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

Subwoofer Vortex Cannon: 300V of “Thwup!”

อังคาร, 06/09/2015 - 09:00

Need a cool toy for your kids? How about something with a bunch of fun fluid dynamics and a tinge of higher-than-average-voltage danger? Did we mention the subwoofer and bank of high-voltage capacitors? Have we got the project for you: [Robert Hart]’s vortex cannon design.

We’ve seen vortex cannons before, where you usually fix a balloon to the back of a trash can. Pull on the balloon membrane and then let it go with a snap, and it sends out a swirling donut of high-pressure air that travels surprisingly far. It’s like smoke rings, but amped up a bit.

[Robert]’s addition is to bolt on a high-power subwoofer in place of the balloon’s rubber membrane, and generate the air pulse by dumping a capacitor bank into the speaker.

The circuit design is a bit more clever than we thought at first. The bottom half is a voltage inverter followed by a diode bridge rectifier that essentially makes 320V DC (peak) out of 12V, and stores this in four fairly large capacitors. A pushbutton activates a relay that dumps the capacitors through the speaker.

On top of the circuit is a -12V voltage inverter. Just before firing, the speaker is pulled back a little bit by applying this -12V to the speaker, and then the relay is triggered and the capacitors dump, shooting the speaker cone forward.

[Robert] is still developing and testing the device out, so if you’re curious or just want to say hi, head on over to Hackaday.io and do so! Be sure to check out his videos. The smoke tests are starting to look good, and we love the control box and high-voltage warning stickers.


Filed under: hardware, misc hacks

Hacking The IM-ME To Open Garages

อังคาร, 06/09/2015 - 06:00

If you have a wireless controlled garage door, a child’s toy can wirelessly open it in a few seconds. [Samy Kamkar] is a security researcher who likes to”think bad, do good”. He’s built OpenSesame, a device that can wirelessly open virtually any fixed-code garage door in seconds, exploiting a new attack he’s discovered in wireless fixed-pin devices, using the Mattel IM-ME toy.

The exploit works only on a gate or garage which uses “fixed codes”. To prevent this type of attack, all you need to do is to upgrade to a system which uses rolling codes, hopping codes, Security+ or Intellicode. These are not foolproof from attack, but do prevent the OpenSesame attack along with other traditional brute forcing attacks. It seems there are at least a couple of vendors who still have such vulnerable products, as well as several more whose older versions are affected too.

Before you read further, a caveat – the code released by [Samy] is intentionally bricked to prevent it from being abused. It might work, but just not quite. If you are an expert in RF and microcontrollers, you could fix it, but then you wouldn’t need his help in the first place, would you?

The IM-ME is a defunct toy and Mattel no longer produces it, but it can be snagged from Amazon or eBay if you’re lucky. The Radica Girltech IM-ME texting toy has been extensively hacked and documented. Not surprising, since it sports a TI CC1110 sub-GHz RF chip, an LCD display, keyboard, backlight, and more.  A good start point is the GoodFET open-source JTAG adapter, followed by the work of [Travis Godspeed] , [Dave] and [Michael Ossmann].

One issue with fixed code systems is their limited key space. For example, a remote with 12 binary dip switches supports 12 bits of possible combinations. Since its binary and 12 bits long, that’s 2^12, which is 4096 possible combinations. With a bit of math, [Samy] shows that it takes 29 minutes to open an (8-12)-bit garage, assuming you know the frequency and baud rate, both of which are pretty common. If you have to attempt a few different frequencies and baud rates, then the time it takes is a multiple of 29 minutes. If you don’t transmit the codes multiple times, and remove the pauses in between codes, the whole exercise can be completed in 3 minutes.

The weak link in the hardware is how the shift registers which decode the received codes work. Each bit is loaded in the register sequentially, gradually moving as additional bits come in and push the previous ones. This, and using an algorithm [Samy] wrote based on the De Bruijn sequence, the whole brute force attack can be completed in just over 8 seconds. OpenSesame implements this algorithm to produce every possible overlapping sequence of 8-12 bits in the least amount of time.

You can take a look at understanding how the code works by checking it out on Github. [Samy] loves doing such investigative work – check out his combo lock code breaker we featured recently, the scary, keyboard sniffing wall wart and the SkyJack – a drone to hack all drones.


Filed under: security hacks

Hard Drive Rootkit Is Frighteningly Persistent

อังคาร, 06/09/2015 - 03:00

There are a lot of malware programs in the wild today, but luckily we have methods of detecting and removing them. Antivirus is an old standby, and if that fails you can always just reformat the hard drive and wipe it clean. That is unless the malware installs itself in your hard drive firmware. [MalwareTech] has written his own frightening proof of concept malware that does exactly this.

The core firmware rootkit needs to be very small in order to fit in the limited memory space on the hard drive’s memory chips. It’s only a few KB in size, but that doesn’t stop it from packing a punch. The rootkit can intercept any IO to and from the disk or the disk’s firmware. It uses this to its advantage by modifying data being sent back to the host computer. When the computer requests data from a sector on the disk, that data is first loaded into the disk’s cache. The firmware can modify the data sitting in the cache before notifying the host computer that the data is ready. This allows the firmware to trick the host system into executing arbitrary code.

[MalwareTech] uses this ability to load his own custom Windows XP bootkit called TinyXPB. All of this software is small enough to fit on the hard drive’s firmware. This means that traditional antivirus cannot detect its presence. If the owner of the system does get suspicious and completely reformats the hard drive, the malware will remain unharmed. The owner cannot even re-flash the firmware using traditional methods since the rootkit can detect this and save itself. The only way to properly re-flash the firmware would be to use an SPI programmer, which would be too technical for most users.

There are many more features and details to this project. If you are interested in malware, the PDF presentation is certainly worth a read. It goes much more in-depth into how the malware actually works and includes more details about how [MalwareTech] was able to actually reverse engineer the original firmware. If you’re worried about this malicious firmware getting out into the wild, [MalwareTech] assures us that he does not intend to release the actual code to the public.


Filed under: security hacks

“Giger Counter” Makes Radiation Detection Surreal

อังคาร, 06/09/2015 - 00:00

Here’s a quick question: are Geiger and Giger (as in H.R. Giger, designer of the Alien Xenomorph) pronounced the same? The answer is no. Nevertheless, the late artist has had his name mispronounced (for the record, it’s ghee-gur) by many over the years. [Steve DeGroof’s] friend posted a goofy tweet that gave him the inspiration to finally put a skeletal lid on the matter, the Giger Counter.

The innards are a Mightyohm Geiger Counter Kit. The external casing is where the true hack lies in this project, made from a 1:2 scale plastic skeleton model, flexible conduit, and dark metallic spray paint. Only the ribcage, some vertebrae, and part of the skull are used from the model. They are assembled in a delightfully inhuman fashion with some conduit wrapped around it and into the bottom of the ribcage for good measure. After some gluing and spray painting, the LED from the Geiger Counter kit is placed through a drilled hole in the skull while the board sits inside the ribcage. Getting the board in and out can be a little tricky, but it looks like the batteries can be changed without having to pull the whole board out.

Check out the video below to see the Giger Counter. If you want another hack inspired by H.R. Giger’s artistic vision, take a look at this Xenomorph suit we covered.  Or, if you can’t get enough Geiger counters, we’ve featured plenty of cool ones on this site.

[via Instructables]


Filed under: how-to, misc hacks

A Mountain of Prizes For Projects Using These Parts

จันทร์, 06/08/2015 - 21:01

Here’s your chance to bring some great stuff home from The Hackaday Prize. For the next 3 weeks we’ll be looking for the best entries using Atmel, Freescale, Microchip, and Texas Instruments parts.

Each of the four contests (yes, four running concurrently) will award the top 50 projects. That’s 200 in total being recognized. The odds are really in your favor — currently some of those lists have less than 50 projects on them — so enter yours right away! Scroll down to see the mountain of prizes that we have for this epic run.

Make Sure We Know About Your Entry

There are two things you need to do to be eligible for this pile of awesome stuff:

  1. Enter your project in the 2015 Hackaday Prize
  2. Leave a comment here with a link to your project and we’ll add it to the list

Do this by the morning of Monday, June 29th to make sure you’re in the running. We’ve been diligent about adding entries to the lists for Atmel, Freescale, Microchip, and Texas Instruments but at the rate new entries have been coming in it’s easy to miss one here or there. Don’t be bashful about asking to be added to these lists!

The prerequisite is to be using a part from one of these four manufacturers. We’ll be looking at these lists for projects using great ideas which have also been well-documented. Tells us why you’re building it, what it does, how you came up with the idea… you know, the whole story!

The Loot

Up for grabs in each of the 4 contests are:

3x Mooshimeters which is a multimeter that uses your smartphone as a wireless readout.

2x DS Logic analyzers which [Adam] reviewed a few weeks back.

15x Stickvise to hold your PCBs (and other things) in place while you work

A continuation of what we’re giving away in each of the 4 contests:

10x Bluefruit LE Sniffers to help you figure out what’s being transmitted by your BTLE devices

10x Cordwood Puzzles; grab your iron and tackle this head-scratching soldering challenge

10x TV-B-Gone is an iconic invention from [Mitch Altman]; one button turns off all TVs

The 2015 Hackaday Prize is sponsored by:
Filed under: contests, Featured, The Hackaday Prize

Lego Printer Prints Lego

จันทร์, 06/08/2015 - 18:00

[Gosse Adema] made his very first instructable by detailing his Lego 3D printer build. It’s Prusa i3 based, and originally started out as an A4 plotter with repurposed steppers out of an old HP printer. After upgrading to some NEMA 17 steppers, it became a full-blown 3D printer.

It turns out that NEMA 17 stepper mounting holes align perfectly with Lego, making it super easy to mount them. Check out this Lego ‘datasheet’ for some great details on measurements.

The brains of the printer are occupied by Marlin running atop a Atmega 2560, and Pronterface for the PC software. He tops it off with a Geeeteck built MK8 extruder boasting a 0.3 mm nozzle that accepts 1.75 mm filament.

As with almost any DIY 3D printer build, his first prints didn’t turn out so well. After adjusting the nozzle and filament size in the software, he started to get some good results. Be sure to check out the video below to see this Lego 3D printer in action.


Filed under: 3d Printer hacks

These Are The Droid Controllers You’ve Been Looking For

จันทร์, 06/08/2015 - 15:00

When I was in the 4th grade our teacher announced that we had a special guest visiting us from somewhere “Far, far away…” As we piled out of the classroom and into to the courtyard, my jaw hit the floor – It was R2D2! The droid started to move around, and made all the noises like the movie. I couldn’t believe what I was seeing. R2D2 was real, and he was right in front of me! (My young mind made the conclusion that if R2D2 was real, then all of Star Wars was real.) I had to turn around to see my friends’ reactions. Unfortunately, it’s at that moment, I saw a middle-aged man, holding a RC transmitter, with antenna extended, standing in the background operating the controls. Sigh. R2 wasn’t real – it’s just a remote-controlled robot. My dreams of becoming a Jedi were forever crushed.

[Chris James] of the R2 Builders Club has been working hard to make a pair of “Stealth RC” controllers to help keep the magic of R2D2 intact.  These dual joystick, 3D printed, hand-held units can be easily hidden in the palm of your hand, or the front pockets of a loose jacket while you operate them. Loaded with features, these tiny controllers use XBee radios to talk to a receiver and custom PCB inside the droid, that in turn, can then control dozens of servos, motors, sound playback and more. Because some R2D2 builds will have dozens and dozens of functions, rather than have a button for each one, [Chris] has programmed in gesture controls in to the unit, so that two controllers and can control several dozen preprogrammed actions. [Chris] hasn’t finalized the design just yet – he still calls it a “beta” build, but so far his documentation is outstanding (PDF) – some of the best we’ve seen.

You can learn more about the R2 Builders Club and the controllers in the video after the break


Filed under: robots hacks

Hackaday Prize Entry: A Light Electric Utility Vehicle

จันทร์, 06/08/2015 - 12:00

[Chris] lives in South Sudan, where there are a lot of poor areas with terrible infrastructure. One of the bigger challenges for this area is getting people and materials over roads that are either bad or don’t exist. Normal vehicles aren’t built for the task, and a Hilux or Land Cruiser is much to expensive. For his Hackaday Prize entry, [Chris] is building a rugged low-cost utility vehicle platform for the developing world.

This battery-powered, four-wheel cart is made out of what [Chris] could find. The frame is made out of 50x50mm angle iron that’s welded together, with the body panels fabricated out of 1200x2400x1.2mm sheet that’s sourced locally. While [Chris] would like better wheels, the cheap Chinese motorcycle wheels are everywhere and cheap – $65, which includes the bearings, breaks, and sprockets. It even has higher ground clearance than the Land Cruiser.

[Chris] already has a prototype of his project built and it’s rolling around. You can check out a video of that below.

The 2015 Hackaday Prize is sponsored by:


Filed under: The Hackaday Prize

Meet us in Shenzhen

จันทร์, 06/08/2015 - 09:01

Hackaday Prize Worldwide is coming to Shenzhen, China at the end of next week! There’s lots to do, join us for as much of it as you can:

Zero to Product Workshop

RSVP now for our Zero to Product workshop on Friday, June 19th. This is created and presented by [Matt Berggren] who shares his experience designing and laying out printed circuit boards professionally. A basic knowledge of electronics is all you need to get going and to lay out the dev board shown here!

Meetup and Share Your Hacks

Holding down an awesome booth at Maker Faire all day makes us weary. We’ll recharge our batteries on Saturday, June 20th starting at 7pm. Join us at Bionic Brew (please be kind and tell us you’re coming). As always, when we hang out we like to see, and show off, hacks. Bring something along if it’s easy to store in a pocket or backpack.

Build some Logic Noise at our SZMF Booth

Yep, we already mentioned it… we’ll be camped out at Shenzhen Maker Faire teaching people how to make music with logic chips. We’ve based the activity off of [Elliot Williams’] fantastic Logic Noise Series. Stop by, say hello and grab some stickers!

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

Hackaday Links: June 7, 2015

จันทร์, 06/08/2015 - 06:00

I’ve said over and over again that Apple’s MagSafe port is the greatest advancement in laptop tech in the last 15 years. Those charger connectors break, though, so how do you fix it? With Lego, of course (Google translatrix). Use a light-colored 1×4 brick so the LED will shine through.

Want to learn Git commands? Here’s a great game that does just that. It’s a really well-designed game/tutorial that walks you through basic Git commands.

Lets say you’re just slightly paranoid about the Bad Guys™ getting into your computer with 0-days and roller blades. You’d like to connect this computer to the Internet, but you don’t want to leave it connected all the time. The solution? A timer for an Ethernet switch. It’s actually a better solution than doing the same thing with scripts: there’s a real, physical interface, and if the Bad Guys™ get in when you are connected, they could just enable the network adapter anyway. An extremely niche use case, but that’s 99% of the security hacks we see.

The DaVinci 3D printer is an okay printer if you’re cool with the Gilette model. The filament cartridges are chipped, and the software is proprietary. These problems have been solved, and now you can use a standard RepRap heated bed and glass with the DaVinci. At this point, people are buying the DaVinci just to tear it apart.


Filed under: Hackaday Columns, Hackaday links

DIY MDF CNC Machine Is Small And Solid

จันทร์, 06/08/2015 - 03:00

In the world of hobby-level CNC cost and simplicity are usually the name of the game. Using inexpensive and easily found materials makes a big difference in the feasibility of a project. [FreeRider] had built a CNC router before but it was big, flexible and not as accurate as he wanted. He set off to design his own table top router, influenced from other designs found on the ‘net, but also keeping the costs down and ease of build up.

The machine frame is made from 3/4″ MDF and was cut on [FreeRider’s] first router, the JGRO. Notice how all the holes are counterbored for the many bolt heads. It is clear that much attention to detail went into the design of this machine. Aluminum angle act as linear rails on which v-wheel bearings travel. Skate bearings support 5/16″ threaded rod used as lead screws. Lead nuts are tapped HDPE blocks and seem to be doing a satisfactory job with minimal backlash.

[FreeRider] says his new machine is capable of 60 inches per minute travel, double that of his old machine. Since the new machine is stiffer, he’s able to route aluminum and has successfully made some brackets out of 1/8″ plate. He reports the dimensional accurate to be about 0.002-0.003 inches. For more inexpensive MDF-based CNC machines, check out this drawer slide bearing one or this one that uses a drill for a spindle.


Filed under: cnc hacks

Better VGA On The STM32F4

จันทร์, 06/08/2015 - 00:00

[Cliff] is pushing VGA video out of a microcontroller at 800×600 resolution and 60 frames per second. This microcontroller has no video hardware. Before we get to the technical overview, here’s the very impressive demo.

The microcontroller in question is the STM32F4, a fairly powerful ARM that we’ve seen a lot of use in some pretty interesting applications. We’ve seen 800×600 VGA on the STM32F4 before, with a circles and text demo and the Bitbox console. [Cliff]’s build is much more capable, though; he’s running 800×600 @ 60FPS with an underclocked CPU and most (90%) of the microcontroller’s resources free.

This isn’t just a demo, though; [Cliff] is writing up a complete tutorial for generating VGA on this chip. It begins with an introduction to pushing pixels, and soon he’ll have a walkthrough on timing and his rasterization framework.

Just because [Cliff] has gone through the trouble of putting together these tutorials doesn’t mean you can’t pull out an STM Discovery board and make your own microcontroller video hacks. [Cliff] has an entire library of for graphics to allow others to build snazzy video apps.


Filed under: Microcontrollers, video hacks

Monitoring Power With A 555

อาทิตย์, 06/07/2015 - 21:00

[Diederich] is running a Raspberry Pi loaded up with Pimatic, a great home automation server that does just about anything you can throw at it. One thing it doesn’t do is monitor electricity and gas directly from the meter – you’re going to need hardware for that. [Diederich] stepped up to the plate and built that hardware using just a 555 timer. The total cost of adding this to his Pimatic setup was less than a dollar.

The 555 can be used as a timer, a trigger, and a bunch of them can be cobbled together into a CPU. [Diederich] isn’t using some fancy logic here; he’s just using the 555 as a Schmitt trigger with a phototransistor and his electricity meter. The output of the 555 is connected to the GPIO of the Raspberry Pi, and a Python script ties into Pimatic.

It’s a neat solution that only costs a dollar, and using the 555 has a few advantages: the 555 makes it possible to use long and thin wires back to the Pi, which means [Diederich]’s Pi doesn’t have to be located right next to his meter.


Filed under: Raspberry Pi

Accessing A PBX Through Voice Channels

อาทิตย์, 06/07/2015 - 18:00

[Alessandro] is an unlucky VoIP PBX administrator that frequently has to deal with very, very dumb network policies. Often times, he’ll have to change something on his setup which requires him to go out to his client’s location, or ask a client to use Teamviewer so the appropriate change can be made from behind a firewall.

This isn’t the solution to the problem. It will, however, fix the problem. To get around these firewalls, [Alessandro] is using the voice channels he already has access to for changing configurations on his VoIP boxes.

The implementation of this uses the AX.25 amateur radio modules that can be found in just about every Linux distro. This, and an Alsa loopback device, allows [Alessandro] to access a terminal over a voice-only network. Is it a hackey kludge? Yep. Is it just a little bit dumb? So are the network policies that don’t allow [Alessandro] to do his job.

This build isn’t too dissimilar than a bunch of modems from the old BBS days, albeit with vastly more powerful software. [Alessandro] says you’re only going to get about 38400bps out of this setup, but it beats begging for help for remote access.


Filed under: Network Hacks

Mad Max Inspired Flamethrower Ukulele

อาทิตย์, 06/07/2015 - 15:00

The new Mad Max movie is getting a lot of buzz, and a few people are calling it a modern classic. There’s a flamethrower guitar in the movie, which means it’s time for cosplay accouterments. Our ‘ol buddy [Caleb] loves flamethrowers and poofers, so hacking together a Doof Warrior inspired flamethrowing ukulele was natural for him.

The fuel for this uke is a can of butane actuated with a caulking gun. This setup is actually pretty clever; by removing the locking tab on the caulking gun, butane is released when the gun’s trigger is squeezed, but stops when the trigger is released. The igniter is a simple grill igniter is used to light the gas.

[Caleb] is rather famous for his flamethrowing creations. His life-size fire-breathing piranha plant uses a similar setup to shoot fire.

Video below.


Filed under: weapons hacks

Hackaday Prize Entry: 3D Printed Parametric Motrs

อาทิตย์, 06/07/2015 - 12:00

If you’re building something that moves, chances are you’ll be using an electric motor. There are tens of thousands of different motors out there, each with their own properties, speeds, torque, and sizes. How do you pick the right motor? Most of the time it’s a highly educated guess, but [Solenoid] has a better idea: just 3D print a motor designed by a calculator that will give you the properties you need

This entry for The Hackaday Prize is just a web-based calculator for motor designs that takes torque, speed, size, or form factor as an input and spits out a complete motor design. Sure, you’ll need to wind coils on a 3D printed frame, but this calculator removes the need to calculate inductance, coil capacitance, and all the other bits needed to construct an efficient motor.

While actual products made in the millions will still be using off the shelf motors, this project is perfect for one-offs. If you want to motorize a telescope mount, this project will design a motor given the power and resolution per steps required. If you want to build a wind turbine, this calculator will put blades right on the outrunner of a brushless motor. It’s a great project, and something we can’t wait to see the results of.

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

Crowdfunding Follies: Debunking The Batteriser

อาทิตย์, 06/07/2015 - 09:00

It’s not on Kickstarter yet, but this product is already making its media debut, with features in all the tech blogs, an astonishing amount of print outlets, and spouted from the gaping maws of easily impressed rubes the world over. What is it? It’s the Batteriser, a tiny metal contraption that clips over AA, C, and D cells that reclaims the power trapped inside every dead battery. Yes, every dead battery you’ve ever thrown away still has up to 80% of its power remaining. Sounds like complete hogwash, right? That’s because it is.

[Dave Jones] put together a great video on the how comes and why nots of the Batteriser, and while doing so gives a great tutorial for debunking a product, heavily inspired by [Carl Sagan]’s Baloney Detection Kit. The real  debunking starts by verifying any assumptions, and the biggest fault of the Batteriser campaign is claiming 80% of a battery’s power is unused. Lucky for us, [Dave] has tons of tools and graphs to demonstrate this is not the case.

To verify the assumption that battery-powered devices will brown out after using only 20% of a battery’s available power, [Dave] does the most logical thing and looks at the data sheets for a battery. After using 20% of available power, these datasheets claim these batteries should be around 1.3V. Do devices brown out at 1.3V? Hook it up to a programmable power supply and find out.

It turns out every battery-powered device [Dave] could find worked perfectly until around 1.1V. Yes, that’s only 0.3V difference from 1.4V claimed by the patent for the Batteriser, but because of the battery discharge curve, that means 80% of the power in a normal device is already being used up. The premise of the Batteriser is invalid, and [Dave] demonstrates it’s a complete scam.

If a through debunking of the Batteriser’s claims wasn’t enough, [Dave] goes on to explain how it may actually be dangerous. The positive terminal of a battery is also the metal can, while the negative terminal is just a tiny nib of metal seperated from the rest of the battery by a gasket. Since the Batteriser is made of metal and serves as the ground for the boost converter circuit, it’s very, very close to shorting through the branding and logo emblazoned on a mylar wrapping each battery is shrouded with. One tiny nick in this insulator, and you have a direct short across the battery. That’s going to turn to heat, and there’s a lot of energy in a D cell; a failure mode for the Batteriser is a fire. That’s just terrible product design.

Video below.


Filed under: Hackaday Columns