Almost every big corporation has a research and development organization, so it came as no surprise when we found a tip about Disney Research in the Hackaday Tip Line. And that the project in question turned out to involve human-safe haptic telepresence robots makes perfect sense, especially when your business is keeping the Happiest Place on Earth running smoothly.
That Disney wants to make sure their Animatronics are safe is good news, but the Disney project is about more than keeping guests healthy. The video after the break and the accompanying paper (PDF link) describe a telepresence robot with a unique hydrostatic transmission coupling it to the operator. The actuators are based on a rolling-diaphragm design that limits hydraulic pressure. In a human-safe system that’s exactly what you want.
The system is a hybrid hydraulic-pneumatic design; two actuators, one powered by water pressure and the other with air, oppose each other in each joint. The air-charged actuators behave like a mass-efficient spring that preloads the hydraulic actuator. This increases safety by allowing the system to be de-energized instantly by venting the air lines. What’s more, the whole system presents very low mechanical impedance, allowing haptic feedback to the operator through the system fluid. This provides enough sensitivity to handle an egg, thread a needle — or even bop a kid’s face with impunity.
There are some great ideas here for robotics hackers, and you’ve got to admire the engineering that went into these actuators. For more research from the House of Mouse, check out this slightly creepy touch-sensitive smart watch, or this air-cannon haptic feedback generator.
Thanks to [GARROW] for this tip.
Filed under: robots hacks
It’s been over a year since the NVIDIA Shield game console/media streamer went on sale. While it’s not clear if NVIDIA plans to launch a new version of the game console this year, it looks like the company might at least have some new hardware on the way.
A new version of the NVIDIA Shield game controller showed up at the FCC website this week.
While there aren’t a lot of details in the FCC listing, the label drawing shows that the shape is a little different than that for the first-gen Shield TV game controller.
Do you always look at it encoded? – Well you have to. The image translators work for the construct program.
Word clocks are supposed to de-encode time into a more readable format. Luckily [Xose Pérez] managed to recover the encoded time signal of the simulation we are all living in with his word clock that displays time using a stylish Matrix code animation.
[Xose] already built his own versions of [Philippe Chrétien’s] Fibonacci Clock and [Jeremy Williams’s] Game Frame, and while doing so he designed a nice little PCB. It’s powered by an ATmega328p, features an RTC with backup battery, an SD-card socket, and it’s ready to drive a bunch of WS2812Bs aka NeoPixels. Since he still had a few spare copies of his design in stock, his new word clock is also driven by this board.
The clock itself is basically a sandwich with a laser-cut smoked acrylic panel for the front and a transparent sheet of acrylic as back support. In between goes a laser-cut cardboard letter mask, a piece of white paper as a diffuser, a 3D printed black matrix, as well as a flexible 16×16 WS2812B panel.
Besides the Matrix effect, [Xose] also implemented a few other display modes and multi-language support in his firmware. All CAD data and the firmware for the clock are available in a Bitbucket repository, and there’s also one for the board’s Gerber files, so you can replicate this build with ease. [Xose’s] clock currently supports Spanish and Catalan, but both the firmware and OpenScad file for the mask can easily be modified to add other languages. Enjoy the video below, where [Xose] offers you two pills demonstrates his build:
Filed under: clock hacks
For years, CodeWeavers has been selling CrossOver software that lets you run some native Windows programs on Linux and Mac computers.
Now the company is getting ready to bring CrossOver to Android, making it possible to run Windows software (including games) on Android phones or tablets, as well as Chromebooks like the Acer Chromebook R11.
A tech preview of CrossOver Android will be available to a group of testers starting August 25th, 2016.
Google Android 7.0 has updated notification and quick settings features, support for viewing multiple apps at the same time, and many other new features. But one change Google didn’t announce? The ability to customize the navigation bar on the bottom of your screen — you know, the space where the home, back, and recents buttons show up.
But a tipster sent Android Police a series of pictures showing that there’s a navigation bar customizer hidden in Android 7.0.
[David Cook]’s summary below the write-up of his experiences working with a bismuth ingot is succinct.
“I wasted a weekend learning why elemental bismuth is not commonly used for metal parts.“
It’s a fair assessment of his time spent growing unspectacular bismuth crystals, casting a bismuth cylinder that cracked, and machining bismuth only to be left with a very rough finish. But even though he admits the exercise was unsuccessful, he does provide us with a fascinating look at the physical properties of the element.This is what [David] wanted to make. Alchemist-hp + Richard Bartz with focus stack. (Own work) [CC BY-SA 3.0], via Wikimedia Commons
Bismuth is one of those elements you pass by in your school chemistry lessons, it has applications in machining alloys and as a lead replacement but most of us have never knowingly encountered it in the real world. It’s one of the heavy metals, below antimony and to the right of lead on the Periodic Table. Curious schoolchildren may have heard that like water it expands on solidifying or that it is diamagnetic, and most of us have probably seen spectacular pictures of its crystals coated in colourful iridescent oxides.
It was a Hackaday story about these crystals that attracted [David] to the metal. It has a low enough melting point – 271.5 °C – that it can be liquified on a domestic stove, so mindful of his marital harmony should he destroy any kitchen appliances he bought a cheap electric ring from Amazon to go with his bismuth ingot. and set to work.
His first discovery was that cheap electric rings outdoors aren’t very effective metallurgy furnaces. Relocating to the kitchen and risking spousal wrath, he did eventually melt his bismuth and pick off the top layer once it had resolidified, to reveal some crystals.These are the bismuth crystals he made.
Unfortunately for him, instead of spectacular colors and huge crystals, the sight that greeted him was one of little brilliance. Small grey crystals with no iridescence. It seems the beautiful samples are made by a very slow cooling of the liquid bismuth, followed by a quick pouring off of the remaining molten metal. Future efforts, he assures us, will involve sand-insulated molds and careful temperature monitoring.
Undeterred, he continued with his stock of bismuth and embarked on the creation of a cylinder. Early efforts with a clay mold resulted in cracked cylinders, so in desperation he cast the entirety of the metal in an aluminium baking tray and cut the resulting ingot to a rough piece of stock for turning.Poor finish on machined bismuth.
With the bismuth in the lathe, he then came face to face with what he alluded to in his conclusion above, why machined bismuth parts aren’t something you’ll encounter. His cylinder came out with significantly rough patches on the surface, because bismuth is both crystalline and brittle. He suggests improvements could be made if the metal could be solidified with fewer crystals, but it’s obvious that elemental bismuth on its own is not a winner in the turning stakes.
We suggest you take a look at [David]’s write-up. It may be presented as a Fail of The Week here, but in fact it’s more of a succession of experiments that didn’t work than an unmitigated disaster. The result is an interesting and well-documented read that we’re sure most Hackaday readers will gain something from.
Aside from the bismuth crystals linked to above, we’ve featured bismuth a few times here at Hackaday. A low-temperature soldering process used it in an alloy, and we’ve even featured someone using it in another alloy to print using a RepRap.
Thanks [nebk] for the tip.Fail of the Week is a Hackaday column which celebrates failure as a learning tool. Help keep the fun rolling by writing about your own failures and sending us a link to the story -- or sending in links to fail write ups you find in your Internet travels.
Filed under: chemistry hacks, Fail of the Week
Google’s Project Fi is a cellular network that blurs the lines between WiFi and mobile data. If you’re at home or another place where you can connect to a WiFi hotspot, the service will route your phone calls over WiFi. But the call will automatically be handed off to a mobile network if you walk out of range of that hotspot.
In order to take advantage of WiFi as often as possible, Project Fi customers can use a feature called Wi-Fi Assistant to automatically connect to open networks whenever they’re detected.
In our final installment of Tools of the Trade (with respect to circuit board assembly), we’ll look at how the circuit board is tested and programmed. At this point in the process, the board has been fully assembled with both through hole and surface mount components, and it needs to be verified before shipping or putting it inside an enclosure. We may have already handled some of the verification step in an earlier episode on inspection of the board, but this step is testing the final PCB. Depending on scale, budget, and complexity, there are all kinds of ways to skin this cat.Hope
This is the least reliable method for PCB testing and verification, but basically it means once the board is done assembling, you do no testing and just assume it will work. Granted, some circuits are simple enough, and their assembly reliable enough, that this might work for a while, and the failure rate is acceptable enough without spending money on testing. Or maybe the product is cheap and you’re selling from China so if it arrives and it doesn’t work the consumer is going to be annoyed but not demand their money back. How many times have you bought something off Alibaba or eBay only to discover it didn’t work when it arrived? Yep, they probably used the “Hope” method of PCB testing.Plug it in
Apply a power source. Does it turn on and blink? You’re good to go. This is the simplest form of functional testing and works on a simple circuit. Functional testing means applying an input and verifying the output. It may be great if the board has an easy power source and only one or two functions and no microcontroller or code that needs to be uploaded.Test Jig
This is more complex than just plugging it in; in this case a special piece of hardware is designed that mates to the circuit board somehow and runs through some tests. If there is some kind of sensor on board, it may test that sensor and verify the output. As an example, a test jig for a smoke alarm could be a box filled with smoke. You put the battery in, drop it in the box, and see if it buzzes. A more complex jig might have pogo pins or servos that actuate switches or other ways of interacting with the board to verify that it works.Programming
The methods described above are useful for cheap circuits and may be adequate. But many PCBs have microcontrollers, and that adds a whole level of difficulty because the microcontroller needs to be programmed, and the circuit will behave differently in different states. The test and programming jigs get a lot more interesting quickly. It should be noted that part of the complexity can be avoided entirely by having the chip manufacturer ship the chips with the firmware already on them. Most of the major manufacturers offer this service. This can be great for a couple reasons: it reduces assembly line complexity, it ensures that the chips are coming from a single trusted vendor and that there are no extra units being made in ghost shifts, and it prevents the factory from stealing the design or selling it to someone else, since they never get access to the firmware. There is a cost associated with this method, though, and it’s generally accepted that you don’t do this unless you’re in pretty substantial volumes and your firmware is locked down and won’t change. This is how the big boys do it. Below that, you have to program them yourself!Pogo pin adapter for programming AVR. This one was designed by Femtocow and is sold on Tindie
So how do you program your device? Well, it depends on the chip manufacturer. Atmel, Microchip, TI, Freescale; they all have their own preferred methods of programming, whether it’s the AVRISP, CC-Debugger, JTAG, or whatever. Most times there will be some kind of header interface, sometimes populated with a connector. It’s best if you can avoid the connector, as it will likely only be used once, is an extra component to populate, and takes up lots of board space. The better option is an edge connector or a pogo pin arrangement. The handy part about the pogo pin option over regular connectors is that you can just leave some bare pads on your PCB and use a special device with some spring pins that press against the PCB and upload the code.
The hardware for doing the programming is usually handled on a device by device basis. In some cases it’s possible to have a panel of PCBs (maybe 2×2) pressed down onto a large pogo pin bed and all of the PCBs are programmed at once, making this step quick. In other cases a jig for a single PCB handles the job. Often there is no record of firmware programming, and the programmer just blindly dumps the code onto the chip every time it is plugged in.
In my experience, I’ve built jigs that are pretty smart, and cost roughly $100. A raspberry pi or cheap android tablet runs it, a python script acts as the UI, and a custom 3D printed jig with pogo pins is the interface to the PCB, connecting through a CC-Debugger or AVRISP programmer. One feature that has been extremely helpful is logging; each device has a MAC address or unique ID, and in the course of programming the Python script grabs that ID and creates a record of what time, firmware version, and any other useful information. This record then gets added to our main device database, so that we can track and support a PCB from the moment it is first programmed.
It’s important to look at cycle time for this step. Every second adds up quickly, so the faster this step can be executed, the better. That means not compiling it every time (like programming from an Arduino). Programmers often have a verify step that is optional and makes sure the microcontroller gets the code, but takes 20 or more seconds. If you are successfully programming every device, do you really need to do the verify step? Later functional testing will show whether the code failed. Look for a cycle time on programming in the 10 seconds or less range. That’s why simultaneous programming can be appealing. Though it increases the cost of the programmer, it can significantly reduce the amount of time needed.Functional Testing
Once the device is programmed, it is good to do additional testing on it. Generally, you can assume that the software doesn’t need to be tested on every device; it’s already been thoroughly tested in the lab and should work just fine (right? RIGHT?). What you want is to make sure that all of the features of the hardware execute the software correctly. Go through the PCB and develop a test that checks every block. First, check that the device powers up. If it doesn’t, there’s no need to test the rest of the PCB. Alert failure and why to the operator, and let them throw it in a rework bin for later. Next test that the microcontroller is functioning. Then have it communicate over the different ports it will be expected to use, like UART, USB, I2C, or others. Then have it interact with the sensors and verify that the sensors are returning values as expected. Flip all the outputs and verify that they work, and apply inputs and make sure that they are read correctly. Have it turn on whatever wireless components are on board and communicate with a device over wireless, and verify that it works. For every part of the circuit, there should be some test you can do to verify that it works, and you can get creative with your test jigs. If you can’t test it, you should question long and hard why it’s on the board in the first place.The calibrator runs all the functional tests once the device is placed in the container; testing a microphone, verifying sensors and communication over Zigbee and USB. The cycle time is about 3 minutes, but two devices go in the box at a time.
In one project I had a sensor that had an LED and a photoresistor. During the testing, we put the device inside the test jig, which was a dark box, and measured the value of the photoresistor with the LED on and off. This way we verified that both components were working. While we could have put an LED and photoresistor on our test jig to verify the two components independently, this was an easy solution that reduced the hardware requirements and narrowed down any potential problems to one of two components that were both easy to debug if the test failed. This same box also played tones of various volumes to test and calibrate the microphone, checked the temperature and humidity sensor over I2C for reasonable values, connected to a ZigBee network, and did all this while talking to the tester over USB, effectively verifying every component of the hardware, and storing all the calibration values to a database, again tied to the MAC address of the device.Boundary Scan Inspection, JTAG
Some of your fancier chips will have fancier capabilities for testing. BGA devices can be very difficult to test successfully. Boundary Scan Inspection is one of the ways to test these small chips through a single JTAG interface. It allows you to run tests which control at a much lower level the values of each pin. Only chips that are compatible with JTAG (IEEE 1149.1 compliant device) can be part of a boundary scan, because these chips have special pins which, when connected to JTAG override the core logic and expose their pins to the JTAG tests. By measuring the value on the other end of the trace, the Boundary Scan Inspection allows measurement of whether there are shorts, opens, testing some board components that aren’t 1149.1 compliant, and even verifying the existence of passives connected to the pins. If you are doing high megahertz processors, FPGAs, or expensive chips, or your board already uses JTAG for programming, then this method of testing might be for you.Other types
We won’t cover X-Ray, AOI, or flying probe testing right now. These are all completely normal testing types for this stage of the process, but we already talked about them in the previous Tools of the Trade article on inspection. Manufacturers will handle the various testing methods at different points in the process based on the complexity of the board and specifications of the client.Tips to make testing/programming easier
- Know how you are going to program the device and expose the connections you need so it’s easy to do. This could be a board edge connector, .1″ header, or bare pads for pogo pins, but plan for it during board layout.
- Have a plan for testing each component of the circuit.
- Collect data during the testing phase. You may need this down the line.
- Put your test points on one side of the board. Doing both sides is really difficult for a jig.
If you are interested in the other Tools of the Trade articles in the series, we have:
Filed under: Engineering, Hackaday Columns, tool hacks
Dell’s XPS 13 line of thin and light laptops tend to have reasonably affordable starting prices of around $800. But if you want a model with a high-resolution touchscreen display, the cheapest option Dell typically offers costs twice as much.
Or you could just buy last year’s model: Adorama is selling an XPS 13 notebook with a 3200 x 1800 pixel display, a Core i5 Broadwell processor, 8GB of RAM, and 256GB of storage for just $800.
There’s no shortage of clock projects, but [niq_ro] has his own take using a vacuum fluorescent display (VFD), and Arduino, and a pair of MAX6921 ICs. Those chips are made to drive a VFD, and the use of two of the ICs required a bit of work. The Arduino is not a great time keeper, so the clock also uses a DS3231 clock module and a humidity and temperature sensor.
The clock is in Romanian, although there are some options for different text. You can find the code on GitHub and can see the result in the video below.
VFDs are often used in places where a display is meant to be read outdoors. It uses cathodoluminescence to actually generate light. The process is similar to a CRT, but at lower voltages. The tubes have a phosphor-coated anode and the cathode bombards it with electrons, making the phosphor glow. VFDs are available in different colors.
VFDs are popular for clocks, ranging from very polished looking ones, to something similar to this one, but with an MSP430. If you are interested in low-level interfacing for VFDs, we’ve talked about that too.
Filed under: Arduino Hacks, clock hacks
With the IFA trade show in Berlin just days away, we can probably expect to see plenty of new laptops, tablets, smartphones and other gadgets. And odds are that one of them will look something like the Lenovo Yoga Tab 3 Plus 10.
WinFuture dug up some information about Lenovo’s unannounced Android tablet with a high-resolution 10 inch display.
The new tablet borrows some design cues from last year’s Yoga Tab 3 and Yoga Tab 3 Pro models.
Google may not be releasing Android 7.0 for older Nexus phones and tablets, but that hasn’t stopped independent developers from doing it. Xda-developers forum member Santhosh M has released an early build of Android 7.0 Nougat for the Google Nexus 5, one of the phones Google is leaving behind.
I suspect this is just the first of many unofficial builds of Android N for hardware that doesn’t officially support the operating system. That’s what happens when you combine an open source operating system, devices with unlockable bootloaders, and a tech savvy community of users.
Imagine this: you come home after a day at work. As you open the door, your nose is the first alert that something is very, very wrong. Instead of the usual house smell, your nose is assaulted with the distinctive aroma that means your dog had an accident. The smell is stronger though — as if Fido brought over a few friends and they all had a party. Flipping the lights on, the true horror is revealed to you. This was a team effort, but only one dog was involved.
At some point after the dog’s deed, Roomba, your robot vacuum, took off on its scheduled daily run around the house. The plucky little robot performed its assigned duties until it found the mess. The cleaning robot then became an agent of destruction, smearing a foul smelling mess throughout the space it was assigned to clean. Technology sometimes has unintended consequences. This time, your technology has turned against you.
This scene isn’t a work of fiction. For a select few families, it has become an all too odoriferous reality just begging for a clever fix.
iRobot’s Roomba has been around for 14 years now. Over the years Roomba has evolved into a complex robotic vacuum. Current models have the iconic front bump sensor, as well as cliff sensors for stairs. A forward IR sensor allows the robot to slow down before striking furniture. Dirt detectors determine if an area is clean, or needs more attention. The flagship 900 series even includes a camera and computer running the Visual Simultaneous Localization and Mapping (vSLAM) algorithm.
All these sensors are great for 99% of the cleaning a Roomba will perform. However, the 1% edge cases are where the demons hide. The demon in this case is a steaming surprise left behind by a pet. [Jesse Newton] found himself in just such a situation last week. His Facebook post on the subject quickly went viral. An iRobot spokesperson was quoted in The Guardian as saying “Quite honestly, we see this a lot. We generally tell people to try not to schedule your vacuum if you know you have dogs that may create such a mess. With animals anything can happen.” The spokesperson went on to say that their engineers are working on the issue. If the spokesperson (and The Guardian) are to be believed, Somewhere inside iRobot, there is an engineer contemplating all the life choices that brought them to this assignment: designing a system to allow the robot to detect pet droppings.
iRobot, the company behind the little circular robot, was quick to embrace the hacker community. Many models of the Roomba include a serial connection. There is even a special Create model for hackers, schools, and makers. Here at Hackaday we believe in giving back. iRobot has given quite a bit to the hacker community over the years. Helping the beleaguered iRobot engineers in their quest to detect the disgusting is the least we can do.
It turns out that sensing animal or human waste is no easy task. Here are a few ideas we came up with:
- Methane – The most familiar method for hackers would be methane detection. We have low cost sensors such as the MQ-4 that are specifically designed for this. In fact, that’s exactly what [IntStarFoo] is testing out in this YouTube video. The problem is that the methane isn’t produced by the fecal matter itself, but the bacteria which are along for the ride. The anaerobic bacterial process takes time, so a fresh sample may not have a detectable amount of methane around it.
- Methanethiol – one of the chief contributors to aroma of human or animal waste is methanethiol, or methyl mercaptan. Detectable by humans down to 1 part per billion (ppb), this is the same chemical added to natural gas to give it that distinctive smell. When a nose is not present, methanethiol is often detected using field sampling followed by gas chromatography in the lab. Sensors do exist, but they are up around $500 USD.
- Other gasses – waste emits a potpourri of gasses, including hydrogen (H2), methane (CH4), carbon dioxide (CO2), hydrogen sulfide (H2S), methanethiol (CH3SH), and dimethyl sulfide (CH3SCH3). Perhaps combinations of these gases could be used as indicators that man’s best friend is having a bad day.
- Cameras – High end Roombas already have a camera. However, it is facing up at too steep an angle to detect anything directly in front of the robot. Adding a front facing camera similar to the hazcams used in Mars rovers might be helpful here. This would also help keep Roomba from knocking over trash cans. The downside is that not all droppings are created equal. The medical industry has provided us with The Bristol Scale, which ranges from Type 1: Separate hard lumps, like nuts, to Type 7: Watery, no solid pieces, entirely liquid. It would take some creative vision programming to detect all types.
- Conductivity – waste will have a water content. An array of conductivity sensors along the front of the robot could detect if it is pushing on something wet.
These are just a few seed ideas to get you started. For the real answers we turn it over to you, our readers. How would you help iRobot through this dilemma? To put it more bluntly, how would you teach a robot to detect poo?
Filed under: Featured, Interest, Original Art, robots hacks, slider
Amateur radio has a couple of sweet allocations in the VHF bands, but because the signals don’t reflect off the ionosphere like shortwave signals, the use is limited basically to line-of-sight. One workaround is to use a repeater with a tall antenna, but that requires a lot of infrastructure or a mountainside lair.
What if you could just fly your antenna up in a drone? Well, for starters, you’d run out of batteries pretty quickly unless you could power it remotely. And if you try to tether it, the supply wires end up being too heavy to lift. Or do they?!?!
This is where our story gets strange. [Glenn, n6gn] has built a rig that transmits significant power over distance using a very thin wire. The trick is to send the power at high-frequency down the wire, at which point it becomes more like a transmission line than a conductor. (We’re not 100% on the physics here.) The signal is rectified to DC on the other end and, in this case, used to power the quadcopter. Check out the video (embedded below) where [Glenn] walks through an early test setup.
[Glenn] isn’t quite there yet, but he’s been able to send almost 200 watts down 0.32 mm wire and he’s proven the basic principles of operation using balloons for lift. There are a few PDFs that get into more detail on [Glenn]’s website, and some of them are reprints of his articles in the ARRL’s QEX journal of experimental ham radio projects. These experiments are all conducted with ham-friendly parts and cardboard, so there’s nothing stopping you from trying this out yourself.
Thanks [Martin] for the tip!
Filed under: radio hacks
[Andrew Peterson] was looking for a way to indulge in his retro gaming passions in a more contemporary manner. His 3D NES emulator “N3S” for Windows brings Nintendo classics to the HoloLens, turning pixels into voxels, and Super Mario into an augmented reality gingerbread man.
To run NES games on the HoloLens, [Andrew’s] emulator uses the Nestopia libretro core. Since AR glasses cry for an augmentation of the game itself, the N3S re-emulates the NES’ picture processing unit (PPU), allowing it to interpret a Nintendo game’s graphics in a 3D space. [Andrew] also put together a comprehensive explanation of how the original Nintendo PPU works, and how he re-implemented it for the HoloLens.
The current version of the N3S PPU emulator automatically generates voxels by simply extruding the original pattern data from the game’s ROM, but [Andrew] is thinking about more features. Users could sculpt their own 3D versions of the original graphic elements in an inbuilt editor, and model sets could then be made available in an online database. From there, players would just download 3D mods for their favorite games and play them on the HoloLens.
According to [Andrew], the emulator reaches the limits of what the current pre-production version of the HoloLens can render fluently, so the future of this project may depend on future hardware generations. Nevertheless, the HoloLens screen capture [Andrew] recorded makes us crave for more augmented retro gaming. Enjoy the video!
Filed under: nintendo hacks, Virtual Reality
We are going to great lengths to turn a quick idea into an electronic prototype, be it PCB milling, home etching or manufacturing services that ship PCBs around the world. Unwilling to accept the complications of PCB fabrication, computer science student [Varun Perumal Chadalavada] came up with an express solution for PCB prototyping: Printem – a Polaroid-like film for instant-PCBs.
Printem is a photosensitive multi-layer assembly, similar to presensitized copper clad – but with an instant development feature. It consists of a thin conductive copper foil that is held to a transparent carrier substrate by a photocurable adhesive film. The other side of the copper features a layer of holding adhesive and a peel-off back side.
To turn the Printem film into a PCB, a negative of the copper traces is printed onto the transparent substrate with help of a regular inkjet or laser printer (a). The film is then exposed to UV light (b). Where light shines through the printed mask, the photo-adhesive cures and selectively fuses the copper film to the substrate. After exposure, the back-side with the holding adhesive is peeled off (c), taking the un-fused copper-portion with it.
The copper layer is very thin, about 100 times thinner than on regular PCBs, and breaks clean enough around the contours of the exposed regions to form copper traces. The result is a flexible PCB (d) that, depending on the substrate material (acetate or polyimide), can even be soldered at low temperatures. For those who want to learn more about how Printem works, [Varun] has put together an interesting writeup on Hackaday.io.
Printem is a project at the DGP (Dynamic Graphics Project) lab of the University Of Toronto and has been recognized by the University as one of the Inventions of the Year. As co-founder of Printem, Ph.D. Student and busy inventor [Varun] now works on the commercialization of his instant PCBs with support of the University’s accelerator network. Enjoy the explanatory video below and let us know what you think of this in the comments!The HackadayPrize2016 is Sponsored by:
Filed under: The Hackaday Prize, tool hacks
The HTC Vive is a virtual reality system designed to work with Steam VR. The system seeks to go beyond just a headset in order to make an entire room a virtual reality environment by using two base stations that track the headset and controller in space. The hardware is very exciting because of the potential to expand gaming and other VR experiences, but it’s already showing significant potential for hackers as well — in this case with robotics location and navigation.
Autonomous robots generally utilize one of two basic approaches for locating themselves: onboard sensors and mapping to see the world around it (like how you’d get your bearings while hiking), or sensors in the room which tell the robot where it is (similar to your GPS telling you where you are in the city). Each method has its strengths and weaknesses, of course. Onboard sensors are traditionally expensive if you need very accurate position data, and GPS location data is far too inaccurate to be of use on a smaller scale than city streets.
[Limor] immediately saw the potential in the HTC Vive to solve this problem, at least for indoor applications. Using the Vive Lighthouse base stations, he’s able to locate the system’s controller in 3D space to within 0.3mm. He’s then able to use this data on a Linux system and integrate it into ROS (Robot Operating System). [Limor] hasn’t yet built a robot to utilize this approach, but the significant cost savings ($800 for a complete Vive, but only the Lighthouses and controller are needed) is sure to make this a desirable option for a lot of robot builders. And, as we’ve seen, integrating the Vive hardware with DIY electronics should be entirely possible.
Filed under: robots hacks, Virtual Reality
A DIY USB power bank made from an old laptop battery from DoItYourselfGadgets:
A situation many can relate to: an empty smartphone battery and no outlet around! That’s exactly why I recycled an old laptop battery into an USB power bank.
This article will show you the basic powerbank circuit consisting of Lithium cell charging circuit, boost converter and toggle switch as well as my improved version with self activating boost converter and LED status indicator and homemade housing.
More details at DoItYourselfGadgets project page.
Check out the video after the break.
Cutting out precise shapes requires a steady hand, a laser cutter, or a CNC mill, right? Nope! All you need is PCB design software and a fabrication facility that’ll do the milling for you. That’s the secret sauce in [bobricius]’s very pleasing seven-segment display design.
His Hackaday.io entry doesn’t have much detail beyond the pictures and the board files, but we’re not sure we need that many either. The lowest board in the three-board stack has Charlieplexed LEDs broken out to six control pins. Next up is a custom-routed spacer board — custom routed by the PCB house, that is. And the top board in the stack is another PCB, this one left clear of copper where the light shines out.
We want to see this thing lit up! We’ve played around with using PCB epoxy material as a LED diffuser before ourselves, and it can look really good. The spacers should help even out the illumination within segments, while preventing bleed across them. Next step? A matrix of WS2812s with custom-routed spacers and diffusers. How awesome would that be?
Filed under: led hacks
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