Tag Archives: Voltage

Enchanting images with Inky Lines, a Pi‑powered polargraph

Post Syndicated from Helen Lynn original https://www.raspberrypi.org/blog/enchanting-images-inky-lines-pi-powered-polargraph/

A hanging plotter, also known as a polar plotter or polargraph, is a machine for drawing images on a vertical surface. It does so by using motors to control the length of two cords that form a V shape, supporting a pen where they meet. We’ve featured one on this blog before: Norbert “HomoFaciens” Heinz’s video is a wonderfully clear introduction to how a polargraph works and what you have to consider when you’re putting one together.

Today, we look at Inky Lines, by John Proudlock. With it, John is creating a series of captivating and beautiful pieces, and with his most recent work, each rendering of an image is unique.

The Inky Lines plotter draws a flock of seagulls in blue ink on white paper. The print head is suspended near the bottom left corner of the image, as the pen inks the wing of a gull

An evolving project

The project isn’t new – John has been working on it for at least a couple of years – but it is constantly evolving. When we first spotted it, John had just implemented code to allow the plotter to produce mesmeric, spiralling patterns.

A blue spiral pattern featuring overlapping "bubbles"
A dense pink spiral pattern, featuring concentric circles and reminiscent of a mandala
A blue spirograph-type pattern formed of large overlapping squares, each offset from its neighbour by a few degrees, producing a four-spiral-armed "galaxy" shape where lines overlap. The plotter's print head is visible in a corner of the image

But we’re skipping ahead. Let’s go back to the beginning.

From pixels to motor movements

John starts by providing an image, usually no more than 100 pixels wide, to a Raspberry Pi. Custom software that he wrote evaluates the darkness of each pixel and selects a pattern of a suitable density to represent it.

The two cords supporting the plotter’s pen are wound around the shafts of two stepper motors, such that the movement of the motors controls the length of the cords: the program next calculates how much each motor must move in order to produce the pattern. The Raspberry Pi passes corresponding instructions to two motor circuits, which transform the signals to a higher voltage and pass them to the stepper motors. These turn by very precise amounts, winding or unwinding the cords and, very slowly, dragging the pen across the paper.

A Raspberry Pi in a case, with a wide flex connected to a GPIO header
The Inky Lines plotter's print head, featuring cardboard and tape, draws an apparently random squiggle
A large area of apparently random pattern drawn by the plotter

John explains,

Suspended in-between the two motors is a print head, made out of a new 3-d modelling material I’ve been prototyping called cardboard. An old coat hanger and some velcro were also used.

(He’s our kind of maker.)

Unique images

The earlier drawings that John made used a repeatable method to render image files as lines on paper. That is, if the machine drew the same image a number of times, each copy would be identical. More recently, though, he has been using a method that yields random movements of the pen:

The pen point is guided around the image, but moves to each new point entirely at random. Up close this looks like a chaotic squiggle, but from a distance of a couple of meters, the human eye (and brain) make order from the chaos and view an infinite number of shades and a smoother, less mechanical image.

An apparently chaotic squiggle

This method means that no matter how many times the polargraph repeats the same image, each copy will be unique.

A gallery of work

Inky Lines’ website and its Instagram feed offer a collection of wonderful pieces John has drawn with his polargraph, and he discusses the different techniques and types of image that he is exploring.

A 3 x 3 grid of varied and colourful images from inkylinespolargraph's Instagram feed

They range from holiday photographs, processed to extract particular features and rendered in silhouette, to portraits, made with a single continuous line that can be several hundred metres long, to generative images spirograph images like those pictured above, created by an algorithm rather than rendered from a source image.

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More power to your Pi

Post Syndicated from James Adams original https://www.raspberrypi.org/blog/pi-power-supply-chip/

It’s been just over three weeks since we launched the new Raspberry Pi 3 Model B+. Although the product is branded Raspberry Pi 3B+ and not Raspberry Pi 4, a serious amount of engineering was involved in creating it. The wireless networking, USB/Ethernet hub, on-board power supplies, and BCM2837 chip were all upgraded: together these represent almost all the circuitry on the board! Today, I’d like to tell you about the work that has gone into creating a custom power supply chip for our newest computer.

Raspberry Pi 3 Model B+, with custome power supply chip

The new Raspberry Pi 3B+, sporting a new, custom power supply chip (bottom left-hand corner)

Successful launch

The Raspberry Pi 3B+ has been well received, and we’ve enjoyed hearing feedback from the community as well as reading the various reviews and articles highlighting the solid improvements in wireless networking, Ethernet, CPU, and thermal performance of the new board. Gareth Halfacree’s post here has some particularly nice graphs showing the increased performance as well as how the Pi 3B+ keeps cool under load due to the new CPU package that incorporates a metal heat spreader. The Raspberry Pi production lines at the Sony UK Technology Centre are running at full speed, and it seems most people who want to get hold of the new board are able to find one in stock.

Powering your Pi

One of the most critical but often under-appreciated elements of any electronic product, particularly one such as Raspberry Pi with lots of complex on-board silicon (processor, networking, high-speed memory), is the power supply. In fact, the Raspberry Pi 3B+ has no fewer than six different voltage rails: two at 3.3V — one special ‘quiet’ one for audio, and one for everything else; 1.8V; 1.2V for the LPDDR2 memory; and 1.2V nominal for the CPU core. Note that the CPU voltage is actually raised and lowered on the fly as the speed of the CPU is increased and decreased depending on how hard the it is working. The sixth rail is 5V, which is the master supply that all the others are created from, and the output voltage for the four downstream USB ports; this is what the mains power adaptor is supplying through the micro USB power connector.

Power supply primer

There are two common classes of power supply circuits: linear regulators and switching regulators. Linear regulators work by creating a lower, regulated voltage from a higher one. In simple terms, they monitor the output voltage against an internally generated reference and continually change their own resistance to keep the output voltage constant. Switching regulators work in a different way: they ‘pump’ energy by first storing the energy coming from the source supply in a reactive component (usually an inductor, sometimes a capacitor) and then releasing it to the regulated output supply. The switches in switching regulators effect this energy transfer by first connecting the inductor (or capacitor) to store the source energy, and then switching the circuit so the energy is released to its destination.

Linear regulators produce smoother, less noisy output voltages, but they can only convert to a lower voltage, and have to dissipate energy to do so. The higher the output current and the voltage difference across them is, the more energy is lost as heat. On the other hand, switching supplies can, depending on their design, convert any voltage to any other voltage and can be much more efficient (efficiencies of 90% and above are not uncommon). However, they are more complex and generate noisier output voltages.

Designers use both types of regulators depending on the needs of the downstream circuit: for low-voltage drops, low current, or low noise, linear regulators are usually the right choice, while switching regulators are used for higher power or when efficiency of conversion is required. One of the simplest switching-mode power supply circuits is the buck converter, used to create a lower voltage from a higher one, and this is what we use on the Pi.

A history lesson

The BCM2835 processor chip (found on the original Raspberry Pi Model B and B+, as well as on the Zero products) has on-chip power supplies: one switch-mode regulator for the core voltage, as well as a linear one for the LPDDR2 memory supply. This meant that in addition to 5V, we only had to provide 3.3V and 1.8V on the board, which was relatively simple to do using cheap, off-the-shelf parts.

Pi Zero sporting a BCM2835 processor which only needs 2 external switchers (the components clustered behind the camera port)

When we moved to the BCM2836 for Raspberry Pi Model 2 (and subsequently to the BCM2837A1 and B0 for Raspberry Pi 3B and 3B+), the core supply and the on-chip LPDDR2 memory supply were not up to the job of supplying the extra processor cores and larger memory, so we removed them. (We also used the recovered chip area to help fit in the new quad-core ARM processors.) The upshot of this was that we had to supply these power rails externally for the Raspberry Pi 2 and models thereafter. Moreover, we also had to provide circuitry to sequence them correctly in order to control exactly when they power up compared to the other supplies on the board.

Power supply design is tricky (but critical)

Raspberry Pi boards take in 5V from the micro USB socket and have to generate the other required supplies from this. When 5V is first connected, each of these other supplies must ‘start up’, meaning go from ‘off’, or 0V, to their correct voltage in some short period of time. The order of the supplies starting up is often important: commonly, there are structures inside a chip that form diodes between supply rails, and bringing supplies up in the wrong order can sometimes ‘turn on’ these diodes, causing them to conduct, with undesirable consequences. Silicon chips come with a data sheet specifying what supplies (voltages and currents) are needed and whether they need to be low-noise, in what order they must power up (and in some cases down), and sometimes even the rate at which the voltages must power up and down.

A Pi3. Power supply components are clustered bottom left next to the micro USB, middle (above LPDDR2 chip which is on the bottom of the PCB) and above the A/V jack.

In designing the power chain for the Pi 2 and 3, the sequencing was fairly straightforward: power rails power up in order of voltage (5V, 3.3V, 1.8V, 1.2V). However, the supplies were all generated with individual, discrete devices. Therefore, I spent quite a lot of time designing circuitry to control the sequencing — even with some design tricks to reduce component count, quite a few sequencing components are required. More complex systems generally use a Power Management Integrated Circuit (PMIC) with multiple supplies on a single chip, and many different PMIC variants are made by various manufacturers. Since Raspberry Pi 2 days, I was looking for a suitable PMIC to simplify the Pi design, but invariably (and somewhat counter-intuitively) these were always too expensive compared to my discrete solution, usually because they came with more features than needed.

One device to rule them all

It was way back in May 2015 when I first chatted to Peter Coyle of Exar (Exar were bought by MaxLinear in 2017) about power supply products for Raspberry Pi. We didn’t find a product match then, but in June 2016 Peter, along with Tuomas Hollman and Trevor Latham, visited to pitch the possibility of building a custom power management solution for us.

I was initially sceptical that it could be made cheap enough. However, our discussion indicated that if we could tailor the solution to just what we needed, it could be cost-effective. Over the coming weeks and months, we honed a specification we agreed on from the initial sketches we’d made, and Exar thought they could build it for us at the target price.

The chip we designed would contain all the key supplies required for the Pi on one small device in a cheap QFN package, and it would also perform the required sequencing and voltage monitoring. Moreover, the chip would be flexible to allow adjustment of supply voltages from their default values via I2C; the largest supply would be capable of being adjusted quickly to perform the dynamic core voltage changes needed in order to reduce voltage to the processor when it is idling (to save power), and to boost voltage to the processor when running at maximum speed (1.4 GHz). The supplies on the chip would all be generously specified and could deliver significantly more power than those used on the Raspberry Pi 3. All in all, the chip would contain four switching-mode converters and one low-current linear regulator, this last one being low-noise for the audio circuitry.

The MXL7704 chip

The project was a great success: MaxLinear delivered working samples of first silicon at the end of May 2017 (almost exactly a year after we had kicked off the project), and followed through with production quantities in December 2017 in time for the Raspberry Pi 3B+ production ramp.

The team behind the power supply chip on the Raspberry Pi 3 Model B+ (group of six men, two of whom are holding Raspberry Pi boards)

Front row: Roger with the very first Pi 3B+ prototypes and James with a MXL7704 development board hacked to power a Pi 3. Back row left to right: Will Torgerson, Trevor Latham, Peter Coyle, Tuomas Hollman.

The MXL7704 device has been key to reducing Pi board complexity and therefore overall bill of materials cost. Furthermore, by being able to deliver more power when needed, it has also been essential to increasing the speed of the (newly packaged) BCM2837B0 processor on the 3B+ to 1.4GHz. The result is improvements to both the continuous output current to the CPU (from 3A to 4A) and to the transient performance (i.e. the chip has helped to reduce the ‘transient response’, which is the change in supply voltage due to a sudden current spike that occurs when the processor suddenly demands a large current in a few nanoseconds, as modern CPUs tend to do).

With the MXL7704, the power supply circuitry on the 3B+ is now a lot simpler than the Pi 3B design. This new supply also provides the LPDDR2 memory voltage directly from a switching regulator rather than using linear regulators like the Pi 3, thereby improving energy efficiency. This helps to somewhat offset the extra power that the faster Ethernet, wireless networking, and processor consume. A pleasing side effect of using the new chip is the symmetric board layout of the regulators — it’s easy to see the four switching-mode supplies, given away by four similar-looking blobs (three grey and one brownish), which are the inductors.

Close-up of the power supply chip on the Raspberry Pi 3 Model B+

The Pi 3B+ PMIC MXL7704 — pleasingly symmetric

Kudos

It takes a lot of effort to design a new chip from scratch and get it all the way through to production — we are very grateful to the team at MaxLinear for their hard work, dedication, and enthusiasm. We’re also proud to have created something that will not only power Raspberry Pis, but will also be useful for other product designs: it turns out when you have a low-cost and flexible device, it can be used for many things — something we’re fairly familiar with here at Raspberry Pi! For the curious, the product page (including the data sheet) for the MXL7704 chip is here. Particular thanks go to Peter Coyle, Tuomas Hollman, and Trevor Latham, and also to Jon Cronk, who has been our contact in the US and has had to get up early to attend all our conference calls!

The MXL7704 design team celebrating on Pi Day — it takes a lot of people to design a chip!

I hope you liked reading about some of the effort that has gone into creating the new Pi. It’s nice to finally have a chance to tell people about some of the (increasingly complex) technical work that makes building a $35 computer possible — we’re very pleased with the Raspberry Pi 3B+, and we hope you enjoy using it as much as we’ve enjoyed creating it!

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Raspberry Pi 3 Model B+ on sale now at $35

Post Syndicated from Eben Upton original https://www.raspberrypi.org/blog/raspberry-pi-3-model-bplus-sale-now-35/

Here’s a long post. We think you’ll find it interesting. If you don’t have time to read it all, we recommend you watch this video, which will fill you in with everything you need, and then head straight to the product page to fill yer boots. (We recommend the video anyway, even if you do have time for a long read. ‘Cos it’s fab.)

A BRAND-NEW PI FOR π DAY

Raspberry Pi 3 Model B+ is now on sale now for $35, featuring: – A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU – Dual-band 802.11ac wireless LAN and Bluetooth 4.2 – Faster Ethernet (Gigabit Ethernet over USB 2.0) – Power-over-Ethernet support (with separate PoE HAT) – Improved PXE network and USB mass-storage booting – Improved thermal management Alongside a 200MHz increase in peak CPU clock frequency, we have roughly three times the wired and wireless network throughput, and the ability to sustain high performance for much longer periods.

If you’ve been a Raspberry Pi watcher for a while now, you’ll have a bit of a feel for how we update our products. Just over two years ago, we released Raspberry Pi 3 Model B. This was our first 64-bit product, and our first product to feature integrated wireless connectivity. Since then, we’ve sold over nine million Raspberry Pi 3 units (we’ve sold 19 million Raspberry Pis in total), which have been put to work in schools, homes, offices and factories all over the globe.

Those Raspberry Pi watchers will know that we have a history of releasing improved versions of our products a couple of years into their lives. The first example was Raspberry Pi 1 Model B+, which added two additional USB ports, introduced our current form factor, and rolled up a variety of other feedback from the community. Raspberry Pi 2 didn’t get this treatment, of course, as it was superseded after only one year; but it feels like it’s high time that Raspberry Pi 3 received the “plus” treatment.

So, without further ado, Raspberry Pi 3 Model B+ is now on sale for $35 (the same price as the existing Raspberry Pi 3 Model B), featuring:

  • A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU
  • Dual-band 802.11ac wireless LAN and Bluetooth 4.2
  • Faster Ethernet (Gigabit Ethernet over USB 2.0)
  • Power-over-Ethernet support (with separate PoE HAT)
  • Improved PXE network and USB mass-storage booting
  • Improved thermal management

Alongside a 200MHz increase in peak CPU clock frequency, we have roughly three times the wired and wireless network throughput, and the ability to sustain high performance for much longer periods.

Behold the shiny

Raspberry Pi 3B+ is available to buy today from our network of Approved Resellers.

New features, new chips

Roger Thornton did the design work on this revision of the Raspberry Pi. Here, he and I have a chat about what’s new.

Introducing the Raspberry Pi 3 Model B+

Raspberry Pi 3 Model B+ is now on sale now for $35, featuring: – A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU – Dual-band 802.11ac wireless LAN and Bluetooth 4.2 – Faster Ethernet (Gigabit Ethernet over USB 2.0) – Power-over-Ethernet support (with separate PoE HAT) – Improved PXE network and USB mass-storage booting – Improved thermal management Alongside a 200MHz increase in peak CPU clock frequency, we have roughly three times the wired and wireless network throughput, and the ability to sustain high performance for much longer periods.

The new product is built around BCM2837B0, an updated version of the 64-bit Broadcom application processor used in Raspberry Pi 3B, which incorporates power integrity optimisations, and a heat spreader (that’s the shiny metal bit you can see in the photos). Together these allow us to reach higher clock frequencies (or to run at lower voltages to reduce power consumption), and to more accurately monitor and control the temperature of the chip.

Dual-band wireless LAN and Bluetooth are provided by the Cypress CYW43455 “combo” chip, connected to a Proant PCB antenna similar to the one used on Raspberry Pi Zero W. Compared to its predecessor, Raspberry Pi 3B+ delivers somewhat better performance in the 2.4GHz band, and far better performance in the 5GHz band, as demonstrated by these iperf results from LibreELEC developer Milhouse.

Tx bandwidth (Mb/s)Rx bandwidth (Mb/s)
Raspberry Pi 3B35.735.6
Raspberry Pi 3B+ (2.4GHz)46.746.3
Raspberry Pi 3B+ (5GHz)102102

The wireless circuitry is encapsulated under a metal shield, rather fetchingly embossed with our logo. This has allowed us to certify the entire board as a radio module under FCC rules, which in turn will significantly reduce the cost of conformance testing Raspberry Pi-based products.

We’ll be teaching metalwork next.

Previous Raspberry Pi devices have used the LAN951x family of chips, which combine a USB hub and 10/100 Ethernet controller. For Raspberry Pi 3B+, Microchip have supported us with an upgraded version, LAN7515, which supports Gigabit Ethernet. While the USB 2.0 connection to the application processor limits the available bandwidth, we still see roughly a threefold increase in throughput compared to Raspberry Pi 3B. Again, here are some typical iperf results.

Tx bandwidth (Mb/s)Rx bandwidth (Mb/s)
Raspberry Pi 3B94.195.5
Raspberry Pi 3B+315315

We use a magjack that supports Power over Ethernet (PoE), and bring the relevant signals to a new 4-pin header. We will shortly launch a PoE HAT which can generate the 5V necessary to power the Raspberry Pi from the 48V PoE supply.

There… are… four… pins!

Coming soon to a Raspberry Pi 3B+ near you

Raspberry Pi 3B was our first product to support PXE Ethernet boot. Testing it in the wild shook out a number of compatibility issues with particular switches and traffic environments. Gordon has rolled up fixes for all known issues into the BCM2837B0 boot ROM, and PXE boot is now enabled by default.

Clocking, voltages and thermals

The improved power integrity of the BCM2837B0 package, and the improved regulation accuracy of our new MaxLinear MxL7704 power management IC, have allowed us to tune our clocking and voltage rules for both better peak performance and longer-duration sustained performance.

Below 70°C, we use the improvements to increase the core frequency to 1.4GHz. Above 70°C, we drop to 1.2GHz, and use the improvements to decrease the core voltage, increasing the period of time before we reach our 80°C thermal throttle; the reduction in power consumption is such that many use cases will never reach the throttle. Like a modern smartphone, we treat the thermal mass of the device as a resource, to be spent carefully with the goal of optimising user experience.

This graph, courtesy of Gareth Halfacree, demonstrates that Raspberry Pi 3B+ runs faster and at a lower temperature for the duration of an eight‑minute quad‑core Sysbench CPU test.

Note that Raspberry Pi 3B+ does consume substantially more power than its predecessor. We strongly encourage you to use a high-quality 2.5A power supply, such as the official Raspberry Pi Universal Power Supply.

FAQs

We’ll keep updating this list over the next couple of days, but here are a few to get you started.

Are you discontinuing earlier Raspberry Pi models?

No. We have a lot of industrial customers who will want to stick with the existing products for the time being. We’ll keep building these models for as long as there’s demand. Raspberry Pi 1B+, Raspberry Pi 2B, and Raspberry Pi 3B will continue to sell for $25, $35, and $35 respectively.

What about Model A+?

Raspberry Pi 1A+ continues to be the $20 entry-level “big” Raspberry Pi for the time being. We are considering the possibility of producing a Raspberry Pi 3A+ in due course.

What about the Compute Module?

CM1, CM3 and CM3L will continue to be available. We may offer versions of CM3 and CM3L with BCM2837B0 in due course, depending on customer demand.

Are you still using VideoCore?

Yes. VideoCore IV 3D is the only publicly-documented 3D graphics core for ARM‑based SoCs, and we want to make Raspberry Pi more open over time, not less.

Credits

A project like this requires a vast amount of focused work from a large team over an extended period. Particular credit is due to Roger Thornton, who designed the board and ran the exhaustive (and exhausting) RF compliance campaign, and to the team at the Sony UK Technology Centre in Pencoed, South Wales. A partial list of others who made major direct contributions to the BCM2837B0 chip program, CYW43455 integration, LAN7515 and MxL7704 developments, and Raspberry Pi 3B+ itself follows:

James Adams, David Armour, Jonathan Bell, Maria Blazquez, Jamie Brogan-Shaw, Mike Buffham, Rob Campling, Cindy Cao, Victor Carmon, KK Chan, Nick Chase, Nigel Cheetham, Scott Clark, Nigel Clift, Dominic Cobley, Peter Coyle, John Cronk, Di Dai, Kurt Dennis, David Doyle, Andrew Edwards, Phil Elwell, John Ferdinand, Doug Freegard, Ian Furlong, Shawn Guo, Philip Harrison, Jason Hicks, Stefan Ho, Andrew Hoare, Gordon Hollingworth, Tuomas Hollman, EikPei Hu, James Hughes, Andy Hulbert, Anand Jain, David John, Prasanna Kerekoppa, Shaik Labeeb, Trevor Latham, Steve Le, David Lee, David Lewsey, Sherman Li, Xizhe Li, Simon Long, Fu Luo Larson, Juan Martinez, Sandhya Menon, Ben Mercer, James Mills, Max Passell, Mark Perry, Eric Phiri, Ashwin Rao, Justin Rees, James Reilly, Matt Rowley, Akshaye Sama, Ian Saturley, Serge Schneider, Manuel Sedlmair, Shawn Shadburn, Veeresh Shivashimper, Graham Smith, Ben Stephens, Mike Stimson, Yuree Tchong, Stuart Thomson, John Wadsworth, Ian Watch, Sarah Williams, Jason Zhu.

If you’re not on this list and think you should be, please let me know, and accept my apologies.

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PipeCam: the low-cost underwater camera

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/pipecam-low-cost-underwater-camera/

Fred Fourie is building a low-cost underwater camera for shallow deployment, and his prototypes are already returning fascinating results. You can build your own PipeCam, and explore the undiscovered depths with a Raspberry Pi and off-the-shelf materials.

PipeCam underwater Raspberry Pi Camera

Materials and build

In its latest iteration, PipeCam consists of a 110mm PVC waste pipe with fittings and a 10mm perspex window at one end. Previous prototypes have also used plumbing materials for the body, but this latest version employs heavy-duty parts that deliver the good seal this project needs.

PipeCam underwater Raspberry Pi Camera

In testing, Fred and a friend determined that the rig could withstand 4 bar of pressure. This is enough to protect the tech inside at the depths Fred plans for, and a significant performance improvement on previous prototypes.

PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera

Inside the pipe are a Raspberry Pi 3, a camera module, and a real-time clock add-on board. A 2.4Ah rechargeable lead acid battery powers the set-up via a voltage regulator.

Using foam and fibreboard, Fred made a mount that holds everything in place and fits snugly inside the pipe.

PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera

PipeCam will be subject to ocean currents, not to mention the attentions of sea creatures, so it’s essential to make sure that everything is held securely inside the pipe – something Fred has learned from previous versions of the project.

Software

It’s straightforward to write time-lapse code for a Raspberry Pi using Python and one of our free online resources, but Fred has more ambitious plans for PipeCam. As well as a Python script to control the camera, Fred made a web page to display the health of the device. It shows battery level and storage availability, along with the latest photo taken by the camera. He also made adjustments to the camera’s exposure settings using raspistill. You can see the effect in this side-by-side comparison of the default python-picam image and the edited raspistill one.

PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera

Underwater testing

Fred has completed the initial first test of PipeCam, running the device under water for an hour in two-metre deep water off the coast near his home. And the results? Well, see for yourself:

PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera
PipeCam underwater Raspberry Pi Camera

PipeCam is a work in progress, and you can read Fred’s build log at the project’s Hackaday.io page, so be sure to follow along.

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Raspbery Pi-newood Derby

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/pinewood-derby/

Andre Miron’s Pinewood Derby Instant Replay System (sorry, not sorry for the pun in the title) uses a Raspberry Pi to monitor the finishing line and play back a slow-motion instant replay, putting an end to “No, I won!” squabbles once and for all.

Raspberry Pi Based Pinewood Derby Instant Replay Demo

This is the same system I demo in this video (https://youtu.be/-QyMxKfBaAE), but on our actual track with real pinewood derby cars. Glad to report that it works great!

Pinewood Derby

For those unfamiliar with the term, the Pinewood Derby is a racing event for Cub Scouts in the USA. Cub Scouts, often with the help of a guardian, build race cars out of wood according to rules regarding weight, size, materials, etc.

Pinewood derby race car

The Cubs then race their cars in heats, with the winners advancing to district and council races.

Who won?

Andre’s Instant Replay System registers the race cars as they cross the finishing line, and it plays back slow-motion video of the crossing on a monitor. As he explains on YouTube:

The Pi is recording a constant stream of video, and when the replay is triggered, it records another half-second of video, then takes the last second and a half and saves it in slow motion (recording is done at 90 fps), before replaying.

The build also uses an attached Arduino, connected to GPIO pin 5, to trigger the recording and playback as it registers the passing cars via a voltage splitter. Additionally, the system announces the finishing places on a rather attractive-looking display above the finishing line.

Pinewood derby race car Raspberry Pi

The result? No more debate about whose car crossed the line first in neck-and-neck races.

Build your own

Andre takes us through the physical setup of the build in the video below, and you’ll find the complete code pasted in the description of the video here. Thanks, Andre!

Raspberry Pi based Pinewood Derby Instant Replay System

See the system on our actual track here: https://youtu.be/B3lcQHWGq88 Raspberry Pi based instant replay system, triggered by Arduino Pinewood Derby Timer. The Pi uses GPIO pin 5 attached to a voltage splitter on Arduino output 11 (and ground-ground) to detect when a car crosses the finish line, which triggers the replay.

Digital making in your club

If you’re a member of an various after-school association such as the Scouts or Guides, then using the Raspberry Pi and our free project resources, or visiting a Code Club or CoderDojo, are excellent ways to work towards various badges and awards. So talk to your club leader to discover all the ways in which you can incorporate digital making into your club!

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Internet-enable your microcontroller projects for under $6 with ESP8266 (Opensource.com)

Post Syndicated from ris original https://lwn.net/Articles/715174/rss

David Egts takes
a look
at the ESP8266 Wi-Fi chip, on Opensource.com. “What is
the ESP8266 exactly? The ESP8266 is a 32-bit RISC CPU made by Espressif Systems. Its clock runs at
80MHz, and it supports up to 16MB of flash RAM for program storage. These
specifications are quite impressive when compared to an Arduino UNO, which
runs at 16MHz, only has 32KB of RAM, and is several times more
expensive. Another big difference is that the ESP8266 requires only 3.3
volts of power while most Arduinos require 5 volts. Keep this voltage
difference in mind when extending your existing Arduino knowledge and
projects to the ESP8266 to prevent magic smoke.

Introducing the AWS IoT Button Enterprise Program

Post Syndicated from Tara Walker original https://aws.amazon.com/blogs/aws/introducing-the-aws-iot-button-enterprise-program/

The AWS IoT Button first made its appearance on the IoT scene in October of 2015 at AWS re:Invent with the introduction of the AWS IoT service.  That year all re:Invent attendees received the AWS IoT Button providing them the opportunity to get hands-on with AWS IoT.  Since that time AWS IoT button has been made broadly available to anyone interested in the clickable IoT device.

During this past AWS re:Invent 2016 conference, the AWS IoT button was launched into the enterprise with the AWS IoT Button Enterprise Program.  This program is intended to help businesses to offer new services or improve existing products at the click of a physical button.  With the AWS IoT Button Enterprise Program, enterprises can use a programmable AWS IoT Button to increase customer engagement, expand applications and offer new innovations to customers by simplifying the user experience.  By harnessing the power of IoT, businesses can respond to customer demand for their products and services in real-time while providing a direct line of communication for customers, all via a simple device.

 

 

AWS IoT Button Enterprise Program

Let’s discuss how the new AWS IoT Button Enterprise Program works.  Businesses start by placing a bulk order of the AWS IoT buttons and provide a custom label for the branding of the buttons.  Amazon manufactures the buttons and pre-provisions the IoT button devices by giving each a certificate and unique private key to grant access to AWS IoT and ensure secure communication with the AWS cloud.  This allows for easier configuration and helps customers more easily get started with the programming of the IoT button device.

Businesses would design and build their IoT solution with the button devices and creation of device companion applications.  The AWS IoT Button Enterprise Program provides businesses some complimentary assistance directly from AWS to ensure a successful deployment.  The deployed devices then would only need to be configured with Wi-Fi at user locations in order to function.

 

 

For enterprises, there are several use cases that would benefit from the implementation of an IoT button solution. Here are some ideas:

  • Reordering services or custom products such as pizza or medical supplies
  • Requesting a callback from a customer service agent
  • Retail operations such as a call for assistance button in stores or restaurants
  • Inventory systems for capturing products amounts for inventory
  • Healthcare applications such as alert or notification systems for the disabled or elderly
  • Interface with Smart Home systems to turn devices on and off such as turning off outside lights or opening the garage door
  • Guest check-in/check-out systems

 

AWS IoT Button

At the heart of the AWS IoT Button Enterprise Program is the AWS IoT Button.  The AWS IoT button is a 2.4GHz Wi-Fi with WPA2-PSK enabled device that has three click types: Single click, Double click, and Long press.  Note that a Long press click type is sent if the button is pressed for 1.5 seconds or longer.  The IoT button has a small LED light with color patterns for the status of the IoT button.  A blinking white light signifies that the IoT button is connecting to Wi-Fi and getting an IP address, while a blinking blue light signifies that the button is in wireless access point (AP) mode.  The data payload that is sent from the device when pressed contains the device serial number, the battery voltage, and the click type.

Currently, there are 3 ways to get started building your AWS IoT button solution.  The first option is to use the AWS IoT Button companion mobile app.  The mobile app will create the required AWS IoT resources, including the creation of the TLS 1.2 certificates, and create an AWS IoT rule tied to AWS Lambda.  Additionally, it will enable the IoT button device via AWS IoT to be an event source that invokes a new AWS Lambda function of your choosing from the Lambda blueprints.  You can download the aforementioned mobile apps for Android and iOS below.

 

The second option is to use the AWS Lambda Blueprint Wizard as an easy way to start using your AWS IoT Button. Like the mobile app, the wizard will create the required AWS IoT resources for you and add an event source to your button that invokes a new Lambda function.

The third option is to follow the step by step tutorial in the AWS IoT getting started guide and leverage the AWS IoT console to create these resources manually.

Once you have configured your IoT button successfully and created a simple one-click solution using one of the aforementioned getting started guides, you should be ready to start building your own custom IoT button solution.   Using a click of a button, your business will be able to build new services for customers, offer new features for existing services, and automate business processes to operate more efficiently.

The basic technical flow of an AWS IoT button solution is as follows:

  • A button is clicked and secure connection is established with AWS IoT with TLS 1.2
  • The button data payload is sent to AWS IoT Device Gateway
  • The rules engine evaluates received messages (JSON) published into AWS IoT and performs actions or trigger AWS Services based defined business rules.
  • The triggered AWS Service executes or action is performed
  • The device state can be read, stored and set with Device Shadows
  • Mobile and Web Apps can receive and update data based upon action

Now that you have general knowledge about the AWS IoT button, we should jump into a technical walk-through of building an AWS IoT button solution.

 

AWS IoT Button Solution Walkthrough

We will dive more deeply into building an AWS IoT Button solution with a quick example of a use case for providing one-click customer service options for a business.

To get started, I will go to the AWS IoT console, register my IoT button as a Thing and create a Thing type.  In the console, I select the Registry and then Things options in console menu.

The name of my IoT thing in this example will be TEW-AWSIoTButton.  If you desire to categorize the IoT things, you can create a Thing type and assign a type to similar IoT ‘things’.  I will categorize my IoT thing, TEW-AWSIoTButton, as an IoTButton thing type with a One-click-device attribute key and select Create thing button.

After my AWS IoT button device, TEW-AWSIoTButton, is registered in the Thing Registry, the next step is to acquire the required X.509 certificate and keys.  I will have AWS IoT generate the certificate for this device, but the service allows for to use your own certificates.  Authenticating the connection with the X.509 certificates helps to protect the data exchange between your device and AWS IoT service.

When the certificates are generated with AWS IoT, it is important that you download and save all of the files created since the public and private keys will not be available after you leave the download page. Additionally, do not forget to download the root CA for AWS IoT from the link provided on the page with your generated certificates.

The newly created certificate will be inactive, therefore, it is vital that you activate the certificate prior to use.  AWS IoT uses the TLS protocol to authenticate the certificates using the TLS protocol’s client authentication mode.  The certificates enable asymmetric keys to be used with devices, and AWS IoT service will request and validate the certificate’s status and the AWS account against a registry of certificates.  The service will challenge for proof of ownership of the private key corresponding to the public key contained in the certificate.  The final step in securing the AWS IoT connection to my IoT button is to create and/or attach an IAM policy for authorization.

I will choose the Attach a policy button and then select Create a Policy option in order to build a specific policy for my IoT button.  In Name field of the new IoT policy, I will enter IoTButtonPolicy for the name of this new policy. Since the AWS IoT Button device only supports button presses, our AWS IoT button policy will only need to add publish permissions.  For this reason, this policy will only allow the iot:Publish action.

 

For the Resource ARN of the IoT policy, the AWS IoT buttons typically follow the format pattern of: arn: aws: iot: TheRegion: AWSAccountNumber: topic/ iotbutton /ButtonSerialNumber.  This means that the Resource ARN for this IoT button policy will be:

I should note that if you are creating an IAM policy for an IoT device that is not an AWS IoT button, the Resource ARN format pattern would be as follows: arn: aws: iot: TheRegion: AWSAccountNumber: topic/ YourTopic/ OptionalSubTopic/

The created policy for our AWS IoT Button, IoTButtonPolicy, looks as follows:

The next step is to return to the AWS IoT console dashboard, select Security and then Certificates menu options.  I will choose the certificate created in the aforementioned steps.

Then on the selected certificate page, I will select the Actions dropdown on the far right top corner.  In order to add the IoTButtonPolicy IAM policy to the certificate, I will click the Attach policy option.

 

I will repeat all of the steps mentioned above but this time I will add the TEW-AWSIoTButton thing by selecting the Attach thing option.

All that is left is to add the certificate and private key to the physical AWS IoT button and connect the AWS IoT Button to Wi-Fi in order to have the IoT button be fully functional.

Important to note: For businesses that have signed up to participate in the AWS IoT Button Enterprise Program, all of these aforementioned steps; Button logo branding, AWS IoT thing creation, obtaining certificate & key creation, and adding certificates to buttons, are completed for them by Amazon and AWS.  Again, this is to help make it easier for enterprises to hit the ground running in the development of their desired AWS IoT button solution.

Now, going back to the AWS IoT button used in our example, I will connect the button to Wi-Fi by holding the button until the LED blinks blue; this means that the device has gone into wireless access point (AP) mode.

In order to provide internet connectivity to the IoT button and start configuring the device’s connection to AWS IoT, I will connect to the button’s Wi-Fi network which should start with Button ConfigureMe. The first time the connection is made to the button’s Wi-Fi, a password will be required.  Enter the last 8 characters of the device serial number shown on the back of the physical AWS IoT button device.

The AWS IoT button is now configured and ready to build a system around it. The next step will be to add the actions that will be performed when the IoT button is pressed.  This brings us to the AWS IoT Rules engine, which is used to analyze the IoT device data payload coming from the MQTT topic stream and/or Device Shadow, and trigger AWS Services actions.  We will set up rules to perform varying actions when different types of button presses are detected.

Our AWS IoT button solution will be a simple one, we will set up two AWS IoT rules to respond to the IoT button being clicked and the button’s payload being sent to AWS IoT.  In our scenario, a single button click will represent that a request is being sent by a customer to a fictional organization’s customer service agent.  A double click, however, will represent that a text will be sent containing a customer’s fictional current account status.

The first AWS IoT rule created will receive the IoT button payload and connect directly to Amazon SNS to send an email only if the rule condition is fulfilled that the button click type is SINGLE. The second AWS IoT rule created will invoke a Lambda function that will send a text message containing customer account status only if the rule condition is fulfilled that the button click type is DOUBLE.

In order to create the AWS IoT rule that will send an email to subscribers of an SNS topic for requesting a customer service agent’s help, we will go to Amazon SNS and create a SNS topic.

I will create an email subscription to the topic with the fictional subscribed customer service email, which in this case is just my email address.  Of course, this could be several customer service representatives that are subscribed to the topic in order to receive emails for customer assistance requests.

Now returning to the AWS IoT console, I will select the Rules menu and choose the Create rule option. I first provide a name and description for the rule.

Next, I select the SQL version to be used for the AWS IoT rules engine.  I select the latest SQL version, however, if I did not choose to set a version, the default version of 2015-10-08 will be used. The rules engine uses a SQL-like syntax with statements containing the SELECT, FROM, and WHERE clauses.  I want to return a literal string for the message, which is not apart of the IoT button data payload.  I also want to return the button serial number as the accountnum, which are not apart of the payload.  Since the latest version, 2016-03-23, supports literal objects, I will be able to send a custom payload to Amazon SNS.

I have created the rule, all that is left is to add a rule action to perform when the rule is analyzed.  As I mentioned above, an email should be sent to customer service representatives when this rule is triggered by a single IoT button press.  Therefore, my rule action will be the Send a message as an SNS push notification to the SNS topic that I created to send an email to our fictional customer service reps aka me. Remember that the use of an IAM role is required to provide access to SNS resources; if you are using the console you have the option to create a new role or update an existing role to provide the correct permissions.  Also, since I am doing a custom message and pushing to SNS, I select the Message format type to be RAW.

Our rule has been created, now all that is left is for us to test that an email is successfully sent when the AWS IoT button is pressed once, and therefore the data payload has a click type of SINGLE.

A single press of our AWS IoT Button and the custom message is published to the SNS Topic, and the email shown below was sent to the subscribed customer service agents email addresses; in this example, to my email address.

 

In order to create the AWS IoT rule that will send a text via Lambda and a SNS topic for the scenario in which customers request account status to be sent when the IoT Button is pressed twice.  We will start by creating an AWS IoT rule with an AWS Lambda action.  To create this IoT rule, we first need to create a Lambda function and the SNS Topic with a SNS text based subscription.

First, I will go to the Amazon SNS console and create a SNS Topic. After the topic is created, I will create a SNS text subscription for our SNS topic and add a number that will receive the text messages. I will then copy the SNS Topic ARN for use in my Lambda function. Please note, that I am creating the SNS Topic in a different region than previously created SNS topic to use a region with support for sending SMS via SNS. In the Lambda function, I will need to ensure the correct region for the SNS Topic is used by including the region as a parameter of the constructor of the SNS object. The created SNS topic, aws-iot-button-topic-text is shown below.

 

We now will go to the AWS Lambda console and create a Lambda function with an AWS IoT trigger, an IoT Type as IoT Button, and the requested Device Serial Number will be the serial number on the back of our AWS IoT Button. There is no need to generate the certificate and keys in this step because the AWS IoT button is already configured with certificates and keys for secure communication with AWS IoT.

The next is to create the Lambda function,  IoTNotifyByText, with the following code that will receive the IoT button data payload and create a message to publish to Amazon SNS.

'use strict';

console.log('Loading function');
var AWS = require("aws-sdk");
var sns = new AWS.SNS({region: 'us-east-1'});

exports.handler = (event, context, callback) => {
    // Load the message as JSON object 
    var iotPayload = JSON.stringify(event, null, 2);
    
    // Create a text message from IoT Payload 
    var snsMessage = "Attention: Customer Info for Account #: " + event.accountnum + " Account Status: In Good Standing " + 
    "Balance is: 1234.56"
    
    // Log payload and SNS message string to the console and for CloudWatch Logs 
    console.log("Received AWS IoT payload:", iotPayload);
    console.log("Message to send: " + snsMessage);
    
    // Create params for SNS publish using SNS Topic created for AWS IoT button
    // Populate the parameters for the publish operation using required JSON format
    // - Message : message text 
    // - TopicArn : the ARN of the Amazon SNS topic  
    var params = {
        Message: snsMessage,
        TopicArn: "arn:aws:sns:us-east-1:xxxxxxxxxxxx:aws-iot-button-topic-text"
     };
     
     sns.publish(params, context.done);
};

All that is left is for us to do is to alter the AWS IoT rule automatically created when we created a Lambda function with an AWS IoT trigger. Therefore, we will go to the AWS IoT console and select Rules menu option. We will find and select the IoT button rule created by Lambda which usually has a name with a suffix that is equal to the IoT button device serial number.

 

Once the rule is selected, we will choose the Edit option beside the Rule query statement section.

We change the Select statement to return the serial number as the accountnum and click Update button to save changes to the AWS IoT rule.

Time to Test. I click the IoT button twice and wait for the green LED light to appear, confirming a successful connection was made and a message was published to AWS IoT. After a few seconds, a text message is received on my phone with the fictitious customer account information.

 

This was a simple example of how a business could leverage the AWS IoT Button in order to build business solutions for their customers.  With the new AWS IoT Button Enterprise Program which helps businesses in obtaining the quantities of AWS IoT buttons needed, as well as, providing AWS IoT service pre-provisioning and deployment support; Businesses can now easily get started in building their own customized IoT solution.

Available Now

The original 1st generation of the AWS IoT button is currently available on Amazon.com, and the 2nd generation AWS IoT button will be generally available in February.  The main difference in the IoT buttons are the amount of battery life and/or clicks available for the button.  Please note that right now if you purchase the original AWS IoT button, you will receive $20 in AWS credits when you register.

Businesses can sign up today for the AWS IoT Button Enterprise Program currently in Limited Preview. This program is designed to enable businesses to expand their existing applications or build new IoT capabilities with the cloud and a click of an IoT button device.  You can read more about the AWS IoT button and learn more about building solutions with a programmable IoT button on the AWS IoT Button product page.  You can also dive deeper into the AWS IoT service by visiting the AWS IoT developer guide, the AWS IoT Device SDK documentation, and/or the AWS Internet of Things Blog.

 

Tara

Introducing PIXEL

Post Syndicated from Simon Long original https://www.raspberrypi.org/blog/introducing-pixel/

It was just over two years ago when I walked into Pi Towers for the first time. I only had the vaguest idea of what I was going to be doing, but on the first day Eben and I sat down and played with the Raspbian desktop for half an hour, then he asked me “do you think you can make it better?”

origdesk

Bear in mind that at this point I’d barely ever used Linux or Xwindows, never mind made any changes to them, so when I answered “hmmm – I think so”, it was with rather more confidence than I actually felt. It was obvious that there was a lot that could be done in terms of making it a better experience for the user, and I spent many years working in user interface design in previous jobs. But I had no idea where to start in terms of changing Raspbian. I clearly had a bit of a learning curve in front of me…

Well, that was two years ago, and I’ve learnt an awful lot since then. It’s actually surprisingly easy to hack about with the LXDE desktop once you get your head around what all the bits do, and since then I’ve been slowly chipping away at the bits that I felt would most benefit from tweaking. Stuff has slowly been becoming more and more like my original concept for the desktop; with the latest changes, I think the desktop has reached the point where it’s a complete product in its own right and should have its own name. So today, we’re announcing the release of the PIXEL desktop, which will ship with the Foundation’s Raspbian image from now on.

newdesk

PIXEL?

One of the things I said (at least partly in jest) to my colleagues in those first few weeks was that I’d quite like to rename the desktop environment once it was a bit more Pi-specific, and I had the name “pixel” in my mind about two weeks in. It was a nice reminder of my days learning to program in BASIC on the Sinclair ZX81; nowadays, everything from your TV to your phone has pixels on it, but back then it was a uniquely “computer-y” word and concept. I also like crosswords and word games, and once it occurred to me that “pixel” could be made up from the initials of words like Pi and Xwindows, the name stuck in my head and never quite went away. So PIXEL it is, which now officially stands for “Pi Improved Xwindows Environment, Lightweight”.

What’s new?

The latest set of changes are almost entirely to do with the appearance of the desktop; there are some functional changes and a few new applications, about which more below, but this is mostly about making things look nicer.

The first thing you’ll notice on rebooting is that the trail of cryptic boot messages has (mostly) gone, replaced by a splash screen. One feature which has frequently been requested is an obvious version number for our Raspbian image, and this can now be seen at the bottom-right of the splash image. We’ll update this whenever we release a new version of the image, so it should hopefully be slightly easier to know exactly what version you’re running in future.

splash

I should mention that the code for the splash screen has been carefully written and tested, and should not slow down the Pi’s boot process; the time to go from powering on to the desktop appearing is identical, whether the splash is shown or not.

Desktop pictures

Once the desktop appears, the first thing you’ll notice is the rather stunning background image. We’re very fortunate in that Greg Annandale, one of the Foundation’s developers, is also a very talented (and very well-travelled) photographer, and he has kindly allowed us to use some of his work as desktop pictures for PIXEL. There are 16 images to choose from; you can find them in /usr/share/pixel-wallpaper/, and you can use the Appearance Settings application to choose which one you prefer. Do have a look through them, as Greg’s work is well worth seeing! If you’re curious, the EXIF data in each image will tell you where it was taken.

desk2

desk3

desk1

Icons

You’ll also notice that the icons on the taskbar, menu, and file manager have had a makeover. Sam Alder and Alex Carter, the guys responsible for all the cartoons and graphics you see on our website, have been sweating blood over these for the last few months, with Eben providing a watchful eye to make sure every pixel was exactly the right colour! We wanted something that looked businesslike enough to be appropriate for those people who use the Pi desktop for serious work, but with just a touch of playfulness, and Sam and Alex did a great job. (Some of the icons you don’t see immediately are even nicer; it’s almost worth installing some education or engineering applications just so those categories appear in the menu…)

menu

Speaking of icons, the default is now not to show icons in individual application menus. These always made menus look a bit crowded, and didn’t really offer any improvement in usability, not least because it wasn’t always that obvious what the icon was supposed to represent… The menus look cleaner and more readable as a result, since the lack of visual clutter now makes them easier to use.

Finally on the subject of icons, in the past if your Pi was working particularly hard, you might have noticed some yellow and red squares appearing in the top-right corner of the screen, which were indications of overtemperature or undervoltage. These have now been replaced with some new symbols that make it a bit more obvious what’s actually happening; there’s a lightning bolt for undervoltage, and a thermometer for overtemperature.

Windows

If you open a window, you’ll see that the window frame design has now changed significantly. The old window design always looked a bit dated compared to what Apple and Microsoft are now shipping, so I was keen to update it. Windows now have a subtle curve on the corners, a cleaner title bar with new close / minimise / maximise icons, and a much thinner frame. One reason the frame was quite thick on the old windows was so that the grab handles for resizing were big enough to find with the mouse. To avoid this problem, the grab handles now extend slightly outside the window; if you hold the mouse pointer just outside the window which has focus, you’ll see the pointer change to show the handle.

window

Fonts

Steve Jobs said that one thing he was insistent on about the Macintosh was that its typography was good, and it’s true that using the right fonts makes a big difference. We’ve been using the Roboto font in the desktop for the last couple of years; it’s a nice-looking modern font, and it hasn’t changed for this release. However, we have made it look better in PIXEL by including the Infinality font rendering package. This is a library of tweaks and customisations that optimises how fonts are mapped to pixels on the screen; the effect is quite subtle, but it does give a noticeable improvement in some places.

Login

Most people have their Pi set up to automatically log in when the desktop starts, as this is the default setting for a new install. For those who prefer to log in manually each time, the login screen has been redesigned to visually match the rest of the desktop; you now see the login box (known as the “greeter”) over your chosen desktop design, with a seamless transition from greeter to desktop.

login

Wireless power switching

One request we have had in the past is to be able to shut off WiFi and/or Bluetooth completely, particularly on Pi 3. There are now options in the WiFi and Bluetooth menus to turn off the relevant devices. These work on the Pi 3’s onboard wireless hardware; they should also work on most external WiFi and Bluetooth dongles.

You can also now disconnect from an associated wireless access point by clicking on its entry in the WiFi menu.

New applications

There are a couple of new applications now included in the image.

RealVNC have ported their VNC server and viewer applications to Pi, and they are now integrated with the system. To enable the server, select the option on the Interfaces tab in Raspberry Pi Configuration; you’ll see the VNC menu appear on the taskbar, and you can then log in to your Pi and control it remotely from a VNC viewer.

The RealVNC viewer is also included – you can find it from the Internet section of the Applications menu – and it allows you to control other RealVNC clients, including other Pis. Have a look here on RealVNC’s site for more information.

vnc

Please note that if you already use xrdp to remotely access your Pi, this conflicts with the RealVNC server, so you shouldn’t install both at once. If you’re updating an existing image, don’t run the sudo apt-get install realvnc-vnc-server line in the instructions below. If you want to use xrdp on a clean image, first uninstall the RealVNC server with sudo apt-get purge realvnc-vnc-server before installing xrdp. (If the above paragraph means nothing to you, then you probably aren’t using xrdp, so you don’t have to worry about any of it!)

Also included is the new SenseHAT emulator, which was described in a blog post a couple of weeks ago; have a look here for all the details.

sensehat

Updates

There are updates for a number of the built-in applications; these are mostly tweaks and bug fixes, but there have been improvements made to Scratch and Node-RED.

One more thing…

We’ve been shipping the Epiphany web browser for the last couple of years, but it’s now starting to show its age. So for this release (and with many thanks to Gustav Hansen from the forums for his invaluable help with this), we’re including an initial release of Chromium for the Pi. This uses the Pi’s hardware to accelerate playback of streaming video content.

chromium

We’ve preinstalled a couple of extensions; the uBlock Origin adblocker should hopefully keep intrusive adverts from slowing down your browsing experience, and the h264ify extension forces YouTube to serve videos in a format which can be accelerated by the Pi’s hardware.

Chromium is a much more demanding piece of software than Epiphany, but it runs well on Pi 2 and Pi 3; it can struggle slightly on the Pi 1 and Pi Zero, but it’s still usable. (Epiphany is still installed in case you find it useful; launch it from the command line by typing “epiphany-browser”.)

How do I get it?

The Raspbian + PIXEL image is available from the Downloads page on our website now.

To update an existing Jessie image, type the following at the command line:

sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install -y rpi-chromium-mods
sudo apt-get install -y python-sense-emu python3-sense-emu
sudo apt-get install -y python-sense-emu-doc realvnc-vnc-viewer

and then reboot.

If you don’t use xrdp and would like to use the RealVNC server to remotely access your Pi, type the following:

sudo apt-get install -y realvnc-vnc-server

As always, your feedback on the new release is very welcome; feel free to let us know what you think in the comments or on the forums.

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The Carputer

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/the-carputer/

Meet Benjamin, a trainee air traffic controller from the southeast of France.

Benjamin was bored of the simple radio setup in his Peugeot 207. Instead of investing in a new system, he decided to build a carputer using a Raspberry Pi.

Carputer

Seriously, you lot: we love your imagination!

He started with a Raspberry Pi 3. As the build would require wireless connectivity to allow the screen to connect to the Pi, this model’s built-in functionality did away with the need for an additional dongle. 

Benjamin invested in the X400 Expansion Board, which acts as a sound card. The board’s ability to handle a variety of voltage inputs was crucial when it came to hooking the carputer up to the car engine.

Car engine fuse box

Under the hood

As Benjamin advises, be sure to unplug the fusebox before attempting to wire anything into your car. If you don’t… well, you’ll be frazzled. It won’t be pleasant.

Though many touchscreens are available on the market, Benjamin chose to use his Samsung tablet for the carputer’s display. Using the tablet meant he was able to remove it with ease when he left the vehicle, which is a clever idea if you don’t want to leave your onboard gear vulnerable to light-fingered types while the car is unattended.

To hook the Pi up to the car’s antenna, he settled on using an RTL SDR, overcoming connection issues with an adaptor to allow the car’s Fakra socket to access MCX via SMA (are you with us?). 

Carputer

Fakra -> SMA -> MCX.

Benjamin set the Raspberry Pi up as a web server, enabling it as a wireless hotspot. This allows the tablet to connect wirelessly, displaying roadmaps and the media centre on his carputer dashboard, and accessing his music library via a USB flashdrive. The added benefit of using the tablet is that it includes GPS functionality: Benjamin plans to incorporate a 3G dongle to improve navigation by including real-time events such as road works and accidents.

Carputer

The carputer control desk

The carputer build is a neat, clean setup, but it would be interesting to see what else could be added to increase functionality while on the road. As an aviation fanatic, Benjamin might choose to incorporate an ADS-B receiver, as demonstrated in this recent tutorial. Maybe some voice controls using Alexa? Or how about multiple tablets with the ability to access video or RetroPie, to keep his passengers entertained? What would you add?

Carputer with raspberry pi first test

For more details go to http://abartben.wordpress.com/

 

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Raspberry Shake – your personal seismograph

Post Syndicated from Liz Upton original https://www.raspberrypi.org/blog/raspberry-shake-personal-seismograph/

There are some applications for the Raspberry Pi that were a very long way from our minds back in 2009, when we were trying to come up with a computer to get kids programming again. I think it’s fair to say that we did not think we were building a personal seismograph.

Raspberry Shake has blown past its Kickstarter target of $7,000 to raise ten times that amount, and it’s still got a couple of days to go.

Raspberry Shake is sensitive enough to detect earthquakes of magnitude 2 and higher at a distance of 50 miles, and earthquakes of magnitude 4 or greater from 300 miles away. Angel Rodriguez, the maker, says:

It will also record earthquakes of larger magnitudes farther away but it will miss some of the subtleties. Raspberry Shake can detect and record short period (0.5 – 15 Hz) earthquakes; the farther away an earthquake, the less of that range of frequencies can be recorded.

Raspberry Shake seismograph

At the heart of this kit is a geophone: a device that converts movement into voltage. (Think of it as being a bit like a microphone for geology.) Inside the little geophone a coil moves relative to a magnet, creating current. Angel has a nice demonstration of how a geophone works:

What’s inside a Geophone

In order to get data coming from the ground we need a sensor able to detect these data. A geophone is a ground motion transducer that convert ground movement into voltage. Raspberry Shake use a geophone and in this video we are going to show you what’s inside of it.

The little add-on board amplifies and digitises the signal from the geophone, and feeds it to your Raspberry Pi.

The Raspberry Pi time-stamps the data and stores it in a seismic industry standard format and sends it in answer to client requests. Those requests are displayed on your smartphone or computer monitor. The complete system is called a seismograph.

Angel and the other instrument builders behind the Raspberry Shake make seismographs and other equipment for a living. This device is the little brother of a seismograph his team makes for universities and other earthquake observers. It runs the same open-source software that the United States Geological Survey (USGS) uses.

Angel says:

Don’t be fooled by the size and the price. Raspberry Shake is better than many of short-period seismometers in current use by the local networks of the USGS and many developing countries. Several software vendors have, for the first time, provided personal no-cost licenses for this project.

Raspberry Shake will make observatory quality data that can be shared in the worldwide standard SEED format. All modern automated seismology programs used by observatories can use the data from the Raspberry Shake. It’s the Volkswagen of seismometers – yes there are Lamborgini seismographs but both the Lamborghini and the Volkswagen will get you from point A to point B.

To prove it, here’s some data from a Raspberry Shake ($99 if you back the Kickstarter now) against data from a $50,000 professional seismograph. In this image the Raspberry Shake’s data is displayed at the top. Both devices are showing data from the same regional earthquake.

Raspberry Shake (upper) and Nanometric Trillium Compact (lower)

Data from Raspberry Shake (top) and Nanometric Trillium Compact (bottom)

Bringing the affordability of a piece of kit like this down to consumer levels is a real achievement: previously this sort of equipment has only been available to universities, governments and other bodies with the ability to make very big investments. As you’ve probably gathered, we love it: head over to back Raspberry Shake on Kickstarter quickly, before the opportunity’s gone!

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