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Google is pulling the plug on Project Tango in March, 2018

Liliputing - 2 hours 19 minก่อน

Before Apple start shipping a $1000 smartphone with a 3D, depth-sensing camera system on the front, there was Google’s Project Tango technology… which put 3D, depth-sensing camera technology on the back of a phone or tablet. Only two commercial smartphones ever shipped with Project Tango, the Asus Zenfone AR and Lenovo Phab 2 Pro. And […]

Google is pulling the plug on Project Tango in March, 2018 is a post from: Liliputing

A Robot Arm for Virtual Beer Pong

Hackaday - 2 hours 36 minก่อน

Leave it to engineering students to redefine partying. [Hyun], [Justin], and [Daniel] have done exactly that for their final project by building a virtually-controlled robotic arm that plays beer pong.

There are two main parts to this build: a sleeve worn by the user, and the robotic arm itself. The sleeve has IMUs at the elbow and wrist and a PIC32 that calculates their respective angles. The sleeve sends angle data to a second PIC32 where it is translated it into PWM signals and sent to the arm.

There’s a pressure sensor wired sleeve-side that’s worn between forefinger and thumb and functions as a release mechanism. You don’t actually have to fling your forearm forward to get the robot to throw, but you can if you want to. The arm itself is built from three micro servos and mounted for stability. The spoon was a compromise. They tried for a while to mimic fingers, but didn’t have enough time to implement grasping and releasing on top of everything else.

Initially, the team wanted wireless communication between the sleeve and the arm. They got it to work with a pair of XBees, but found that RF was only good for short periods of use. Communication is much smoother over UART, which you can see in the video below.

You don’t have to have a machine shop or even a 3-D printer to build a robot arm. Here’s another bot made from scrap wood whose sole purpose is to dunk tea bags.


Filed under: Beer Hacks, Microcontrollers, Robots Hacks

BlackBerry to phase out support for BB10 and BBOS by end of 2019

Liliputing - 3 hours 30 minก่อน

There hasn’t been a new smartphone running BlackBerry OS since 2015, but BlackBerry hasn’t gone all-in on Android software just yet. The company continues to support devices running BB10 and Blackberry OS… for now. But the clock is ticking. BlackBerry has announced it’ll pull the plug on the BlackBerry World app store on December 31st, […]

BlackBerry to phase out support for BB10 and BBOS by end of 2019 is a post from: Liliputing

Brute Forcing Passwords with a 3D Printer

Hackaday - 4 hours 5 minก่อน

Many of us use a 4 digit pin code to lock our phones. [David Randolph] over at Hak5 has come up a simple way to use a 3D printer to brute force these passwords. Just about every 3D printer out there speaks the same language, G-code. The same language used in CAD and CNC machines for decades.

[David] placed a numeric keypad on the bed of his printer. He then mapped out the height and positions of each key. Once he knew the absolute positions of the keys, it was easy to tell the printer to move to a key, then press and release. He even created a G-code file which would press every one of the 10,000 4 key pin combinations.

A file this large was a bit unwieldy though, so [David] also created a python script which will do the same thing — outputting the G-code and coordinates to brute force any 4 pin keypad. While a printer is quite a bit slower than Hak5’s own USB Rubber Ducky device (which acts as an automated keyboard), it will successfully brute force a password. Although most phones these days do limit the number of password attempts a user gets.

[David] admits this is probably useless in a clandestine/hacking application, but the video is still a great introduction to G-code and using 3D printers for non-printing functions.

Interested in pushing 3D printers to print more than just plastic? You can always print chocolate.


Filed under: 3d Printer hacks

High-speed internet delivered by lasers coming to rural India (thanks to Alphabet’s Project Loon)

Liliputing - 4 hours 36 minก่อน

Alphabet’s Project Loon technology uses hot air balloons to deliver internet access to places where it might not otherwise be available, including rural communities or hurricane-damaged Peurto Rico. But Alphabet is working with Indian internet service provider AP State FiberNet to deliver high-speed internet service to millions of customers in India’s Andhra Pradesh state without […]

High-speed internet delivered by lasers coming to rural India (thanks to Alphabet’s Project Loon) is a post from: Liliputing

Thermistors and 3D Printing

Hackaday - 5 hours 35 minก่อน

I always find it interesting that 3D printers — at least the kind most of us have — are mostly open-loop devices. You tell the head to move four millimeters in the X direction and you assume that the stepper motors will make it so. Because of the mechanics, you can calculate that four millimeters is so many steps and direct the motor to take them. If something prevents that amount of travel you get a failed print. But there is one part of the printer that is part of a closed loop. It is very tiny, very important, but you don’t hear a whole lot about it. The thermistor.

The hot end and the heated bed will both have a temperature sensor that the firmware uses to keep temperatures at least in the ballpark. Depending on the controller it might just do on-and-off “bang-bang” control or it might do something as sophisticated as PID control. But either way, you set the desired temperature and the controller uses feedback from the thermistor to try to keep it there.

If you print with high-temperature materials you might have a thermocouple in your hot end, but most machines use a thermistor. These are usually good to about 300 °C. What got me thinking about this was the installation of an E3D V6 clone hot end into my oldest printer which had a five-year-old hot end in it. I had accumulated a variety of clone parts and had no idea what kind of thermistor was in the heat block I was using.

Does it Matter?

When you build the firmware for your printer, you get to tell it what thermistor you are using. There are a few printers that can switch the thermistor type at runtime and — of course — you could just adjust your temperature settings to account for any error if you knew what they were. You usually use a negative temperature coefficient (NTC) device where the resistance goes down as the temperature goes up. But exactly what resistance corresponds to what temperature depends on the device.

So for my upgrade, the old hot end had a thermistor in it that — I think — was made by Honeywell that the firmware knew about. The new hot end was a total unknown. Most (but not all) common thermistors you’ll use in a printer read 100 kΩ at room temperature and that was true of both of these, as well. I wanted to understand how much off my temperatures would be if I picked up the wrong conversion. Surprisingly, while there was plenty of information about how to read a thermistor, I had not seen much data about error from using an incorrect temperature curve, so I decided to take matters into my own hands.

But First

First, it might be worth to think about what really happens in a typical 3D printer’s temperature sensor. Sure, the thermistor changes value, but what then? Most controllers will have a resistor divider with a fixed resistor and the thermistor and then use an A/D to read the voltage.

You don’t want to pass too much current through the thermistor because that current causes some heating and is a source of error. A typical printer will use a 4.7 kΩ resistor at 5 V to excite the thermistor and read the resulting voltage. Suppose the thermistor is at 500 Ω. The voltage across the thermistor will be 5 * (500/(4700+500)) or about a half volt.

I mentioned that most thermistors you’ll find in a printer read 100 kΩ at room temperature. You might think 500 Ω seems kind of low. In fact, as the device gets hot, the resistance rapidly falls off. A 500 Ω resistance corresponds to around 190 °C in a typical 100 kΩ thermistor.

The microcontroller running the printer has to do the opposite math. That is, it will take the equation above and solve for the resistance. In other words: 0.5 = 5 * (R/4700+500) so solve for R. The problem is you don’t want to set your filament temperature in ohms! You want to use degrees.

The best way to compute temperature from a thermistor reading is the Steinhart-Hart model. This requires three parameters and a little number crunching. However, most 3D printer software uses a simplification that uses just the second parameter, or beta, of the thermistor.

Rather than give you the formula, I’ll point you to this spreadsheet. Column A has some resistance values and the other columns have different beta values and show temperatures in degrees C. If you really want to dig into the math and other applications, check out [Peter Vree’s] video, below.

Big Difference?

Armed with that spreadsheet, it is pretty easy to figure out how big a deal it is to be out of tune with your thermistor. Of course, you’d like to have the right value, but in the case of a generic thermistor, how big of a deal is it?

My methodology was simple. I went to Digikey and searched for thermistors. I used their filters to only look at 100 kΩ NTC devices that could read at least 300 °C and specified a beta at 100 °C. The beta values ranged from 3988 to 4280 and based on price and quantities, the real range was even less spread than that. For example, Digikey only had about 180 of the device with a beta of 4280. Not very scientific, I’ll admit, but it did give me a range of beta values you might expect to find “in the wild.”

If you note on the spreadsheet (and the graph below), there’s not a lot of temperature difference at the typical range you’ll print plastics like PLA, ABS, and PETG. Of course, you could get unlucky. If you do have that bottom-most curve, the temperature is a good bit off for that one. Or maybe you have a one of a kind thermistor that has some wacky value that will be way off. But statistically, you’d think you are going to be in the ballpark even if you can’t change the thermistor table. Now, if either thermistor has a different room-temperature resistance, all bets are off. But most of the 3D printers I’ve seen do use 100 kΩ sensors.

The Result

Although it shouldn’t make much difference, I did make an educated guess based on some heuristics and changed the thermistor type. I thought about trying to set a precise temperature on the thermistor to get a few more data points but decided it wasn’t worth breaking out the sous vide cooker.

After all, every printer is a little different and the temperature the plastic sees probably isn’t the thermistor temperature anyway, so there’s always a little “dialing in” required to determine what temperature your printer needs for a particular job. A difference of five or even ten degrees, then, will be in the noise. You’ll find out your PLA is too runny at 210 °C and drop the temperature to 190 °C. Or perhaps ABS is causing extruder skips and you’ll goose the temperature up a few degrees. You are going to have to do across different brands, or colors, of filament anyway.

At the end, though, I got great results. Who knew that what might be the tiniest part of a 3D printer could be so important? If you look carefully in the photo to the right, there are two thin Teflon-coated wires coming out of the heat block. That’s the thermistor, whatever brand and model number it is.

Thermistors, of course, have lots of other uses. They can be used to limit inrush current, provide temperature-stable bias, and — of course — sense temperature in many different situations. For example, they can be the heart of a very minimalist soldering iron controller.


Filed under: 3d Printer hacks, Hackaday Columns, Original Art

Deals of the Day (12-15-2017)

Liliputing - 6 hours 6 minก่อน

Today’s the last day of Amazon’s device sale, which means it’s probably you last chance this year to pick up an Amazon Fire 7 tablet for $30, an Amazon Fire HD 8 for $50, a Kindle for $60, or an Amazon Echo Show for $150… and it’s almost certainly your last chance to score those […]

Deals of the Day (12-15-2017) is a post from: Liliputing

Reports: Samsung and Xiaomi to launch Windows 10 on Snapdragon devices

Liliputing - ศุกร์, 12/15/2017 - 23:30

Asus and HP are the first two companies to unveil upcoming Windows 10 computers powered by Qualcomm Snapdragon 835 processors. But we already know that Lenovo is working on its own Snapdragon-powered Windows PC. And now Fudzilla reports two more companies want in on that Windows-on-ARM action. Samsung and Xiaomi are both said to be working […]

Reports: Samsung and Xiaomi to launch Windows 10 on Snapdragon devices is a post from: Liliputing

Design a Microcontroller With Security In Mind

Hackaday - ศุกร์, 12/15/2017 - 23:30

There are many parts to building a secure networked device, and the entire industry is still learning how to do it right. Resources are especially constrained for low-cost microcontroller devices. Would it be easier to build more secure devices if microcontrollers had security hardware built-in? That is the investigation of Project Sopris by Microsoft Research.

The researchers customized the MediaTek MT7687, a chip roughly comparable to the hacker darling ESP32. The most significant addition was a security subsystem. It performs tasks notoriously difficult to do correctly in software, such as random number generation and security key storage. It forms the core of what they called the “hardware-based secure root of trust.”

Doing these tasks in a security-specific module solves many problems. If a key is not stored in memory, a memory dump can’t compromise what isn’t there. Performing encryption/decryption in task-specific hardware makes it more difficult to execute successful side-channel attacks against them. Keeping things small keeps the cost down and also eases verifying correctness of the code.

But the security module can also be viewed from a less-favorable perspective. Its description resembles a scaled-down version of the Trusted Platform Module. As a self-contained module running its own code, it resembles the Intel Management Engine, which is currently under close scrutiny.

Will we welcome Project Sopris as a time-saving toolkit for building secure networked devices? Or will we become suspicious of hidden vulnerabilities? The researchers could open-source their work to ease these concerns, but value of their work will ultimately depend on the fast-moving field of networked device security.

Do you know of other efforts to add hardware-assisted security to microcontrollers? Comment below or let us know via the tip line!

[via Wired]

Image of Mount Sopris, namesake of the project, by [Hogs555] (CC-BY 4.0)

 


Filed under: Microcontrollers

Vivo smartphones to be first with under-glass fingerprint sensor from Synaptics

Liliputing - ศุกร์, 12/15/2017 - 22:43

This week Synaptics announced it’s begun mass production of an under-glass, in-display fingerprint sensor and that the company is working with a top five OEM. Earlier this year we’d heard that Chinese smartphone maker Vivo was working on phones with under-glass fingerprint sensors. Coincidence? Nope. In an article for Forbes, Patrick Moorhead says he got […]

Vivo smartphones to be first with under-glass fingerprint sensor from Synaptics is a post from: Liliputing

Hardware Heroes: Isambard Kingdom Brunel

Hackaday - ศุกร์, 12/15/2017 - 22:01

There are some notable figures in history that you know of for just one single thing. They may have achieved much in their lifetimes or they may have only been famous for Andy Warhol’s fifteen minutes, but through the lens of time we only know them for that single achievement. Then on the other hand there are those historic figures for whom there is such a choice of their achievements that have stood the test of time, that it is difficult to characterize them by a single one.

Isambard Kingdom Brunel, in front of the launching chains for the Great Eastern. [Public domain]Such is the case of Isambard Kingdom Brunel, the subject of today’s Hardware Heroes piece. Do we remember him for his involvement in the first successful tunnel to pass beneath a river, as a builder of some of the most impressive bridges on the 19th century, the innovator in all aspects of rail engineering, the man behind the first screw-driven ocean-going iron ship, or do we remember him as all of those and more?

It is possible that if you are not British, or in particular you are not from the West of England, this is the first you’ve heard of Brunel. In which case he is best described as a towering figure of many aspects of engineering over the middle years of the 19th century. His influence extended from civil engineering through the then-emerging rail industry, to shipbuilding and more, and his legacy lives on today in that many of his works are still with us.

Engineering: The Family Trade

Brunel’s father, Marc Brunel, was an engineer and refugee from the French Revolution who found success in providing the British Navy with a mass-production system for wooden pulley blocks as used in the rigging of sailing ships. He enters this story for his grand project, the world’s first tunnel to be dug under a navigable river, beneath London’s River Thames from Rotherhithe to Wapping, and for his patented tunneling shield which made it possible to be dug.

It’s easy to spot that it’s the Brunel Museum.The Thames at Rotherhithe flows over soft ground, and this caused significant problems for the project including a breach, flooding, and recovery. Brunel was his father’s on-site manager after the departure of the first incumbent due to overwork, and continued in the role until the tunnel’s eventual completion, hugely over time and budget, in 1843. The tunnel remains in use today by the London Overground railway, and its two vertical construction shafts have survived. The southern shaft  and its associated engine house are now in use as the Brunel Museum, and we took a trip there on a chilly November morning.

Visiting the Brunel Museum

The museum is not a large one, and has a primary focus on Brunel himself and the tunnel in particular. Its exhibition and video presentation are informative, but not necessarily enough to detain the visitor for too long. The reason you should visit it lies a short walk from the engine house; visitors can descend into the construction shaft itself for a tantalising glimpse at a remnant of Victorian London.

It appears that the shaft leads a double life as an event venue, being we would guess comfortably large enough to place a London bus inside it. So entry is down a modern staircase and there is some modern seating, but once you ignore those you can see some of the original features. The floor is a later addition placed above the train tracks, so periodically you can hear the London Overground beneath your feet, meanwhile the walls are the grimy Victorian brick of the shaft lining. This was laid at ground level as it descended under its own weight while the shaft was dug, and still bears the clearly visible imprint of the original 1840s double staircases that carried the foot passengers who first used the tunnel.

It’s odd, this is on one hand a grimy and relatively featureless place, yet as an engineer it’s simultaneously hallowed ground. The Brunels — both father and son — made this happen alongside the hard work of many nameless Victorian labourers. From this achievement came all the other achievements of Victorian civil engineering from Brunel and those who followed him in the Great Western Railway and his other ventures. If engineering had cathedrals, this might be one of them.

This photograph (taken in low light and edited) does not do justice to the tunnel construction shaft as a space.

A visit to the museum is not complete without a quick run over the road to survey the riverscape, followed by a short walk to Rotherhithe station for a trip through the tunnel itself. To be fair, other than knowing you’re in Brunel’s tunnel it’s just like any other Tube journey, however it is rumoured that when special trains are laid on for enthusiasts they turn off the train lights and leave on the tunnel lighting, allowing passengers to see some of the surviving original brickwork.

Brunel the Railroad Builder

A modern Brunel statue at the GWR Paddington terminus.The tunnel may have been Brunel’s signature early work, but it is not the achievement he is most remembered for. If we were to ask a typical person in the street about him, particularly if they lived in the West of England, we’d be greeted with the instant answer: the Great Western Railway. This was the transport empire that spread westwards from London, initially to Bristol, but then further west to cover the entire West of England and Wales. Brunel was the chief engineer who laid out and surveyed its route, was responsible for its principal structures, and decided its engineering principles including its unique 7’0.25″ broad gauge.

The GWR became such an integral part of that region of the country that it stamped its culture and by extension Brunel’s presence across it. Today his name can be seen in pub signs, street signs, a university and a shopping centre, and the modern-day train operating company. Those passenger trains now cover the area with the renamed moniker GWR and the company is busy adopting the signature green livery of its ancestor.

A Trio of Bridges: Masterpieces All

It is difficult to conceive in an age when highway bridges are prefabricated and assembled in days, just how much of an achievement a single bridge could be. In Brunel’s case there are three of the many bridges he designed that stand out as engineering masterpieces, his brick arches over the Thames at Maidenhead, his twin-span Royal Albert Bridge over the Tamar at Saltash, and the Clifton Suspension Bridge over the Avon gorge just outside Bristol.

The Royal Albert Bridge, Saltash. [by: Geof Sheppard CC BY-SA 3.0]The Maidenhead bridge carries the GWR main line over the Thames, with two arches meeting at a central pier on one of the river’s islands. It is exceptional because both arches take the shape of an extremely low and wide ellipse, which in 1839 upon it opening were the widest and flattest brick arches in the world. Even today when standing under the arch it is a particularly graceful structure. Famously the GWR board were concerned that Brunel had pushed the technology of brick arches too far, so he left the wooden construction supports in place for its first winter until the river’s floods carried them away. 178 years later it still carries all the trains heading for the West of England.

The Saltash bridge carries the GWR main line to Cornwall, in the extreme south west of the country, at high level over the River Tamar. To maintain navigability for sailing ships, it takes the form of two 455-foot wrought iron trusses 100 feet above the water. Each of the trusses contains a pair of ellipses from which the track bed is suspended, giving the bridge its distinctive appearance.

The Clifton Suspension Bridge. [Gothick CC BY-SA 3.0]The Clifton bridge bears Brunel’s name, but as a memorial to him from the civil engineers who completed it after his death. Brunel had completed the stone towers, but the project had foundered for lack of funds in the 1830s. After Brunel’s death it was completed using chains from an earlier Brunel design that had been demolished, and finally opened in 1864. With its spectacular position over a deep gorge it remains one of the most famous views of a suspension bridge in the world, and though today it carries a fairly minor road it is well worth a visit.

Ship Building? Why Not!

The logical extension of a transport network built to serve Western British ports was to establish a shipping line, and Brunel brought his engineering expertise to the design of a series of ships for the Great Western Steamship Company. The Great Western of 1838 was a wooden-hulled paddle steamer, but the ship that followed it, the Great Britain of 1843, was the world’s first iron-hulled screw-driven steamship. As such it was the direct ancestor of all modern shipping, at a time when much of the world’s ocean-going transport still relied on sail power. Astoundingly it survived, eventually being retrieved as a hulk from the Falkland Islands in 1970 and returned to Bristol for restoration and display as a museum ship.

A contemporary picture on the Great Eastern at sea. [Public domain]Brunel’s final maritime design was the 1859 Great Eastern, featuring both screw and paddle wheels as an extreme long-distance ship for the journeys from Britain to India and Australia. The famous photograph of him standing in front of an immense reel of chain is taken at its construction, they are part of its launch chains. The Great Eastern was the largest ship ever built at the time, and would not be surpassed in either size or tonnage until the years surrounding the turn of the 20th century. Upon completion its launch was unsuccessful, and it lay for a few months while a series of hydraulic rams were assembled to force it sideways into the River Thames. Its first sea trial in early September 1859 was marred by a steam explosion, which blew a substantial hole in its deck and toppled one of its funnels into the English Channel.

The pressure of the Great Eastern project had its effect on Brunel’s health, and following the Great Eastern explosion he suffered a stroke and died a few days later on the 15th of September 1859. He is buried in a rather unassuming family plot in Kensal Green Cemetery, London.

The Fails Only Make You Stronger

The projects we’ve described so far in this piece are only the larger and better known among Brunel’s work. Perhaps one day we’ll devote an entire article to his disastrous experiment with an atmospheric railway for instance, or his success with a prefabricated military hospital for the British involvement in the Crimean War. Even our talking about bridges has omitted many interesting structures, his timber viaducts, or the intersection of a canal, road, and railway bridge in a London suburb. To be an engineer like Brunel in the 19th century was to be a polymath, and this is why he’s an obvious choice for a Heroes piece.

Brunel’s memorial on the Embankment.Going back to our journey across London, there are many different possible routes over the London Transport network from the tunnel museum at Rotherhithe to the Great Western Railway terminus at Paddington, but we took one of the less obvious ones to take in one last Brunel site. A couple of stops down the line to Whitechapel and a switch to the District line (green on the Tube map), and a trundle along the Embankment to Temple station where we find after a short walk his memorial statue. It’s a modest structure though clean and not neglected, his bronze stands on a plinth looking down at a pedestrian crossing as the taxis thunder past. Pedestrians barely give it a second glance, as the Embankment is home to a large number of statues of notable people. But then you might ask yourself, why should they? This is Brunel’s monument, but it’s not the monument that matters. Every time you board an express train, every time we use a product that has been transported by rail or ship, and every journey through a tunnel under water, those are his monuments. Stand by a piece of Brunel’s work, if you want to see his real commemoration. Most of it has survived for a century and a half, how many of today’s engineers will be able to say that!

[Source for main image: Royal Museums Greenwich]


Filed under: Featured, History, Slider

BEAM is a wearable, programmable button with an AMOLED display

Liliputing - ศุกร์, 12/15/2017 - 20:00

There are “smart” versions of everything from watches to light bulbs, to toothbrushes these days, for better or worse. So it shouldn’t be surprising that someone decided the pins you attach to your backpack or shirt could be smarter. BEAM is a smart button/pin with a 400 x 400 pixel AMOLED display that can show […]

BEAM is a wearable, programmable button with an AMOLED display is a post from: Liliputing

Modernizing Puerto Rico’s Grid

Hackaday - ศุกร์, 12/15/2017 - 19:00

After two massive hurricanes impacted Puerto Rico three months ago, the island was left with extensive damage to its electrical infrastructure. Part of the problem was that the infrastructure was woefully inadequate to withstand a hurricane impact at all. It is possible to harden buildings and infrastructure against extreme weather, and a new plan to restore Puerto Rico’s power grid will address many of these changes that, frankly, should have been made long ago.

Among the upgrades to the power distribution system are improvements to SCADA systems. SCADA allows for remote monitoring and control of substations, switchgear, and other equipment which minimizes the need for crews to investigate problems and improves reliability. SCADA can also be used for automation on a large scale, in addition to the installation of other autonomous equipment meant to isolate faults and restore power quickly. The grid will get physical upgrades as well, including equipment like poles, wire, and substations that are designed and installed to a more rigorous standard in order to make them more wind- and flood-tolerant. Additional infrastructure will be placed underground as well, and a more aggressive tree trimming program will be put in place.

The plan also calls for some 21st-century improvements as well, including the implementation of “micro grids”. These micro grids reduce the power system’s reliance on centralized power plants by placing small generation facilities (generators, rooftop solar, etc) in critical areas, like at hospitals. Micro grids can also be used in remote areas to improve reliability where it is often impractical or uneconomical to service.

While hurricanes are inevitable in certain parts of the world, the damage that they cause is often exacerbated by poor design and bad planning. Especially in the mysterious world of power generation and distribution, a robust infrastructure is extremely important for the health, safety, and well-being of the people who rely on it. Hopefully these steps will improve Puerto Rico’s situation, especially since this won’t be the last time a major storm impacts the island.


Filed under: Repair Hacks

Retractable Console Allows Wheelchair User to Get up Close and Personal

Hackaday - ศุกร์, 12/15/2017 - 16:00

[Rhonda] has multiple sclerosis (MS), a disease that limits her ability to walk and use her arms. She and the other residents of The Boston Home, an extended care facility for people with MS and other neuromuscular diseases, rely on their wheelchairs for mobility. [Rhonda]’s chair comes with a control console that swings out of the way to allow her to come up close to tables and counters, but she has problems applying enough force to manually position it.

Sadly, [Rhonda]’s insurance doesn’t cover a commercial solution to her problem. But The Boston Home has a fully equipped shop to extend and enhance residents’ wheelchairs, and they got together with students from MIT’s Principles and Practices of Assistive Technology (PPAT) course to hack a solution that’s not only useful for [Rhonda] but should be generally applicable to other chairs. The students analyzed the problem, measured the forces needed and the clearances required, and built a prototype pantograph mount for the control console. They’ve made the device simple to replicate and kept the BOM as inexpensive as possible since patients are often out-of-pocket for enhancements like these. The video below shows a little about the problem and the solution.

Wheelchair hacks are pretty common, like the 2015 Hackaday Prize-winning Eyedrivomatic. We’ve also covered totally open-source wheelchairs, both manual and electric.


Filed under: Medical Hacks

Dumb Coffee Grinder Gets Smarter with Time

Hackaday - ศุกร์, 12/15/2017 - 13:00

[Forklift] has a Rancilio Rocky, a prosumer-level coffee grinder that’s been a popular mainstay for the last few decades. It’s a simple machine with a direct-drive motor. Rocky has one job, and it will do that job in one of 55 slightly different ways as long as someone is pushing the grind button. What Rocky doesn’t have is any kind of metering technology. There’s no way to govern the grind length, so repeatable results rely on visual estimates and/or an external clock. Well, there wasn’t until [Forklift] designed a programmable timer from the ground up.

The timer interface is simple—there’s a D-pad of buttons for navigation through the OLED screen, and one button to start the grind. The left and right buttons move through four programmable presets that get stored in the EEPROM of the timer’s bare ATMega328P brain. Grind duration can be adjusted with the up/down buttons.

We like that [Forklift] chose to power it by piggybacking on the 240VAC going to the grinder. The cord through the existing grommet and connects with spade terminals, so there are no permanent modifications to the grinder. Everything about this project is open source, including the files for the 7-segment font [Forklift] designed.

Tea aficionados may argue that creating their potion is the more time sensitive endeavor. We’ve got you covered there. Only question is, one button or two?


Filed under: Microcontrollers

Putting Wind in VR by Watching the Audio Signal

Hackaday - ศุกร์, 12/15/2017 - 10:00

A simple way to integrate physical feedback into a virtual experience is to use a fan to blow air at the user. This idea has been done before, and the fans are usually the easy part. [Paige Pruitt] and [Sean Spielberg] put a twist on things in their (now-canceled) Kickstarter campaign called ZephVR, which featured two small fans mounted onto a VR headset. The bulk of their work was in the software, which watches the audio signal for recognizable “wind” sounds, and uses those to turn on one or both fans in response.

The benefit of using software to trigger fans based on audio cues is that the whole system works independently of everything else, with no need for developers and software to build in support for your project, or to use other middleware. Unfortunately the downside is that the results are only as good as the ability of software to pick the right sounds and act on them. Embedded below is a short video showing a test in action.

https://ksr-video.imgix.net/assets/019/026/322/2026659792c70076b22c71519b8c8a06_h264_high.mp4

On the left is a debug console, on which red indicates low or no wind and green is a lot of wind. Fans are mounted to the top of the monitor so the responses are visible. It’s not much of a demo, but it’s enough to see the idea in action with fans responding individually to objects passing nearby on the left or right.

[Sean] and [Paige] canceled their campaign despite hitting the funding goal, it seems they decided to change direction and focus on creating a robust software API instead of delving into hardware production. In the meantime, they shared the design files for their prototype hardware. Hopefully some software for people to experiment with will follow suit.

Augmenting virtual experiences with fans is nothing new, but interfacing to the application doesn’t always have to be a challenge. The Superfan project for example discovered that many racing and simulator games already have motion and feedback data that can be accessed and used by custom hardware — as long as one has the right software tools, anyway.


Filed under: Virtual Reality

Reverse Engineering the Nintendo Wavebird

Hackaday - ศุกร์, 12/15/2017 - 07:00

Readers who were firmly on Team Nintendo in the early 2000’s or so can tell you that there was no accessory cooler for the Nintendo GameCube than the WaveBird. Previous attempts at wireless game controllers had generally either been sketchy third-party accessories or based around IR, and in both cases the end result was that the thing barely worked. The WaveBird on the other hand was not only an official product by Nintendo, but used 2.4 GHz to communicate with the system. Some concessions had to be made with the WaveBird; it lacked rumble, was a bit heavier than the stock controllers, and required a receiver “dongle”, but on the whole the WaveBird represented the shape of things to come for game controllers.

Finding the center frequency for the WaveBird

Given the immense popularity of the WaveBird, [Sam Edwards] was somewhat surprised to find very little information on how the controller actually worked. Looking for a project he could use his HackRF on, [Sam] decided to see if he could figure out how his beloved WaveBird communicated with the GameCube. This moment of curiosity on his part spawned an awesome 8 part series of guides that show the step by step process he used to unlock the wireless protocol of this venerable controller.

Even if you’ve never seen a GameCube or its somewhat pudgy wireless controller, you’re going to want to read though the incredible amount of information [Sam] has compiled in his GitHub repository for this project.

Starting with defining what a signal is to begin with, [Sam] walks the reader though Fourier transforms, the different types of modulations, decoding packets, and making sense of error correction. In the end, [Sam] presents a final summation of the wireless protocol, as well as a simple Python tool that let’s the HackRF impersonate a WaveBird and send button presses and stick inputs to an unmodified GameCube.

This amount of work is usually reserved for those looking to create their own controllers from the ground up, so we appreciate the effort [Sam] has gone through to come up with something that can be used on stock hardware. His research could have very interesting applications in the world of “tool-assisted speedruns” or even automating mindless stat-grinding.


Filed under: classic hacks, Nintendo Hacks, Wireless Hacks

GPD Win 2 handheld gaming PC to have new design, 6 inch screen, Core M3 processor

Liliputing - ศุกร์, 12/15/2017 - 05:47

About two months after the first pictures of a GPD Win 2 prototype hit the web, the company has revealed the specs for its 2nd-generation handheld gaming PC. As expected, the new model has a bigger screen, a faster processor, and an improved keyboard to help set it apart from the model I tested last […]

GPD Win 2 handheld gaming PC to have new design, 6 inch screen, Core M3 processor is a post from: Liliputing

Pandora now lets free users listen to songs on-demand (after watching a 15 second ad)

Liliputing - ศุกร์, 12/15/2017 - 05:30

Pandora got is start as a streaming music service that lets you create personalized radio stations by entering an artist or track and then listening to a string of related songs, giving each a thumbs up or down to tune the station to your tastes. But earlier this year the company launched Pandora Premium, a […]

Pandora now lets free users listen to songs on-demand (after watching a 15 second ad) is a post from: Liliputing

3-pound Asus VivoBook 14 breaks cover ahead of CES

Liliputing - ศุกร์, 12/15/2017 - 04:44

Asus has added a few new 14 inch laptops to its website, including a 14 inch model with support for up to an Intel Core i7-8550U quad-core processor and a similar laptop that has the same size, weight, and design… but which also includes NVIDIA GeForce 940MX graphics. Both models are part of the Asus […]

3-pound Asus VivoBook 14 breaks cover ahead of CES is a post from: Liliputing

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