Monthly Archives: May 2017

The ClearWalker is an 8-legged, Arduino-powered Strandbeest

via Arduino Blog

What has eight legs, a tail, and is powered by an Arduino Mega? The ClearWalker, of course!

This Strandbeest-style walker employs two motors, controlled by individual H-bridge relay modules to traverse forwards, backwards, and slowly rotate to one side or another via a hesitating leg motion. You can see how the electronics (including a bunch of LEDs) were integrated into this build in the video below.

If you’d like to try a similar control scheme for your ClearWalker/Strandbeest/treaded vehicle using an Arduino and smartphone, you can find it outlined in this Arduino Project Hub post. For the rest of the steps in this quite involved build, and more rather zany inventions, be sure to check out the “Jeremy Cook’s Projects” YouTube page.

IoTuesday: The Last Mile

via SparkFun Electronics Blog Posts

Right now, most Internet of Things (IoT) devices seem to rely on WiFi or Bluetooth to obtain a connection to the internet. These protocols are ubiquitous in most modern homes and cities. While they are great for providing connection for home automation, biometric monitoring, and city-wide measuring devices, they have a number of shortcomings when it comes to providing “last mile” coverage.

The last mile (or “last kilometer”) refers to the final leg of telecommunications networks that provide service to end users. The issue with WiFi and Bluetooth is that they are generally short-range radio networks. With enough power, they can make line-of-sight links at over a mile, but that also usually requires the end device to also have a powerful transmitter to create a two-way connection.

A few technologies have been gaining popularity for providing multi-mile (multi-kilometer) coverage for things like farms and remote measuring devices. Let’s look at three.

LoRa

alt text

Short for “Long Range,” LoRa and its MAC-layer protocol LoRaWAN is a type of communication for Low-Power Wide-Area Network (LPWAN) designed for low bit-rate communications over long distances, which is perfect for many IoT applications (think remote sensors). LoRa operates below 1 GHz and uses direct sequence spread spectrum, which allows for a longer range than WiFi (assuming same transmit/receive power) and reduced interference. In Europe, LoRa can be found in the 863-870 MHz band and around 915 MHz in the United States (remember cordless phones? Well, that ISM band has become much quieter over the years).

Semtech is one of the leading companies driving development in LoRa, and they set up test base stations (gateways) in Munich, Germany, a few years ago. According to the LoRa Alliance technology page, LoRa can support anywhere between 0.3 to 50 kpbs, depending on the number of devices on the same network.

LoRa is closed source, but some savvy DIYers have connected gateways to Raspberry Pis to create personal LoRa networks.

Sigfox

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Sigfox is a French company started in 2009 focused on building long-range, low-power wireless networks for IoT. Similar to LoRa, Sigfox operates around 868 MHz in Europe and 902 MHz in the US. Sigfox has partnerships with Texas Instruments (TI), Silicon Labs and ON Semiconductor to help produce hardware.

Sigfox technology uses what they call “ultra narrow band,” meaning communication bandwidth is only 100 Hz in their respective bands. It supports between 100-600 bps, depending on the region of operation, and messages can contain up to 12 bytes in the payload for upload (device to base station), and 8 bytes for download (base station to device). Unlike LoRa, Sigfox does not provide private base stations for private uses, which means you’re out of luck if your area does not have coverage.

Here is a great article comparing LoRa and Sigfox.

Cellular

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Even cell carriers want a piece of this LPWAN pie. Last year, the 3GPP (3rd Generation Partnership Project – the collaborative body of telecommunication companies that set standards for things like GSM, 3G and LTE) announced several new categories of LTE (“Long-Term Evolution,” which is often marketed as “4G LTE”). These technologies include EC-GSM-IoT, LTE MTC Cat M1 and NB-IoT. Each of these have different features, but are intended to support more devices per base station with lower data rates (like the dozen biometric sensors we each plan to have cybernetically implanted at some point…).

The slowest of these is Cat NB1, which supports up to 250 kbps but has a reported latency of 1.6-10 seconds (forget gaming on your IoT device). The upside of these new categories is that the infrastructure already exists for areas with cell coverage. However I’m sure I’ll have to sign a two-year contract for each IoT device.

An overview of the new categories can be found here, and if you’d like to read a more in-depth overview of the technology, here is 3GPP’s white paper.

Others

Certainly other last-mile technologies exist when you really need to get data out from remote areas (Iridium anyone?). For your personal projects you have a few options, including maximizing your WiFi, creating your own LoRa gateway or using existing 3G cellular communications. What other ways can you recommend for communicating with devices out of WiFi range?

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IoTuesday: The Last Mile

via SparkFun Electronics Blog Posts

Right now, most Internet of Things (IoT) devices seem to rely on WiFi or Bluetooth to obtain a connection to the internet. These protocols are ubiquitous in most modern homes and cities. While they are great for providing connection for home automation, biometric monitoring, and city-wide measuring devices, they have a number of shortcomings when it comes to providing “last mile” coverage.

The last mile (or “last kilometer”) refers to the final leg of telecommunications networks that provide service to end users. The issue with WiFi and Bluetooth is that they are generally short-range radio networks. With enough power, they can make line-of-sight links at over a mile, but that also usually requires the end device to also have a powerful transmitter to create a two-way connection.

A few technologies have been gaining popularity for providing multi-mile (multi-kilometer) coverage for things like farms and remote measuring devices. Let’s look at three.

LoRa

alt text

Short for “Long Range,” LoRa and its MAC-layer protocol LoRaWAN is a type of communication for Low-Power Wide-Area Network (LPWAN) designed for low bit-rate communications over long distances, which is perfect for many IoT applications (think remote sensors). LoRa operates below 1 GHz and uses direct sequence spread spectrum, which allows for a longer range than WiFi (assuming same transmit/receive power) and reduced interference. In Europe, LoRa can be found in the 863-870 MHz band and around 915 MHz in the United States (remember cordless phones? Well, that ISM band has become much quieter over the years).

Semtech is one of the leading companies driving development in LoRa, and they set up test base stations (gateways) in Munich, Germany, a few years ago. According to the LoRa Alliance technology page, LoRa can support anywhere between 0.3 to 50 kpbs, depending on the number of devices on the same network.

LoRa is closed source, but some savvy DIYers have connected gateways to Raspberry Pis to create personal LoRa networks.

Sigfox

alt text

Sigfox is a French company started in 2009 focused on building long-range, low-power wireless networks for IoT. Similar to LoRa, Sigfox operates around 868 MHz in Europe and 902 MHz in the US. Sigfox has partnerships with Texas Instruments (TI), Silicon Labs and ON Semiconductor to help produce hardware.

Sigfox technology uses what they call “ultra narrow band,” meaning communication bandwidth is only 100 Hz in their respective bands. It supports between 100-600 bps, depending on the region of operation, and messages can contain up to 12 bytes in the payload for upload (device to base station), and 8 bytes for download (base station to device). Unlike LoRa, Sigfox does not provide private base stations for private uses, which means you’re out of luck if your area does not have coverage.

Here is a great article comparing LoRa and Sigfox.

Cellular

alt text

Even cell carriers want a piece of this LPWAN pie. Last year, the 3GPP (3rd Generation Partnership Project – the collaborative body of telecommunication companies that set standards for things like GSM, 3G and LTE) announced several new categories of LTE (“Long-Term Evolution,” which is often marketed as “4G LTE”). These technologies include EC-GSM-IoT, LTE MTC Cat M1 and NB-IoT. Each of these have different features, but are intended to support more devices per base station with lower data rates (like the dozen biometric sensors we each plan to have cybernetically implanted at some point…).

The slowest of these is Cat NB1, which supports up to 250 kbps but has a reported latency of 1.6-10 seconds (forget gaming on your IoT device). The upside of these new categories is that the infrastructure already exists for areas with cell coverage. However I’m sure I’ll have to sign a two-year contract for each IoT device.

An overview of the new categories can be found here, and if you’d like to read a more in-depth overview of the technology, here is 3GPP’s white paper.

Others

Certainly other last-mile technologies exist when you really need to get data out from remote areas (Iridium anyone?). For your personal projects you have a few options, including maximizing your WiFi, creating your own LoRa gateway or using existing 3G cellular communications. What other ways can you recommend for communicating with devices out of WiFi range?

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YouTube live-streaming made easy

via Raspberry Pi

Looking to share your day, event, or the observations of your nature box live on the internet via a Raspberry Pi? Then look no further, for Alex Ellis has all you need to get started with YouTube live-streaming from your Pi.

YouTube live-streaming Docker Raspberry Pi

The YouTube live dashboard. Image c/o Alex Ellis

If you spend any time on social media, be it Facebook, Instagram, YouTube, or Twitter, chances are you’ve been notified of someone ‘going live’.

Live-streaming video on social platforms has become almost ubiquitous, whether it’s content by brands, celebrities, or your cousin or nan – everyone is doing it.

Even us!

Live from Pi Towers – Welcome

Carrie Anne and Alex offer up a quick tour of the Pi Towers lobby while trying to figure out how Facebook Live video works.

YouTube live-streaming with Alex Ellis and Docker

In his tutorial, Alex demonstrates an easy, straightforward approach to live-streaming via a Raspberry Pi with the help of a Docker image of FFmpeg he has built. He says that with the image, instead of “having to go through lots of manual steps, we can type in a handful of commands and get started immediately.”

Why is the Docker image so helpful?

As Alex explains on his blog, if you want to manually configure your Raspberry Pi Zero for YouTube live-streaming, you need to dedicate more than a few hours of your day.

Normally this would have involved typing in many manual CLI commands and waiting up to 9 hours for some video encoding software (ffmpeg) to compile itself.

Get anything wrong (like Alex did the first time) and you have to face another nine hours of compilation time before you’re ready to start streaming – not ideal if your project is time-sensitive.

Alex Ellis on Twitter

See you in 8-12 hours? Building ffmpeg on a my @Raspberry_Pi #pizero with @docker

Using the Docker image

In his tutorial, Alex uses a Raspberry Pi Zero and advises that the project will work with either Raspbian Jessie Lite or PIXEL. Once you’ve installed Docker, you can pull the FFmpeg image he has created directly to your Pi from the Docker Hub. (We advise that while doing so, you should feel grateful to Alex for making the image available and saving you so much time.)

It goes without saying that you’ll need a YouTube account in order to live-stream to YouTube; go to the YouTube live streaming dashboard to obtain a streaming key.

Alex Ellis on Twitter

Get live streaming to @YouTube with this new weekend project and guide using your @Raspberry_Pi and @docker. https://t.co/soqZ9D9jbS

For a comprehensive breakdown of how to stream to YouTube via a Raspberry Pi, head to Alex’s blog. You’ll also find plenty of other Raspberry Pi projects there to try out.

Why live-stream from a Raspberry Pi?

We see more and more of our community members build Raspberry Pi projects that involve video capture. The minute dimensions of the Raspberry Pi Zero and Zero W make them ideal for fitting into robots, nature boxes, dash cams, and more. What better way to get people excited about your video than to share it with them live?

If you have used a Raspberry Pi to capture or stream footage, make sure to link to your project in the comments below. And if you give Alex’s Docker image a go, do let us know how you get on.

The post YouTube live-streaming made easy appeared first on Raspberry Pi.

The Fleischer 100: Pi-powered sound effects

via Raspberry Pi

If there’s one thing we like more than a project video, it’s a project video that has style. And that’s exactly what we got for the Fleischer 100, a Raspberry Pi-powered cartoon sound effects typewriter created by James McCullen.

The Fleischer 100 | Cartoon Sound Effects Toy

The goal of this practical project was to design and make a hardware device that could play numerous sound effects by pressing buttons and tweaking knobs and dials. Taking inspiration from old cartoons of the 1930s in particular – the sound effects would be in the form of mostly conventional musical instruments that were often used to create sound effects in this period of animation history.

The golden age of Foley

Long before the days of the drag-and-drop sound effects of modern video editing software, there were Foley artists. These artists would create sound effects for cartoons, films, and even live performances, often using everyday objects. Here are Orson Welles and the King of Cool himself, Dean Martin, with a demonstration:

Dean Martin & Orson Welles – Early Radio/Sound Effects

Uploaded by dino4ever on 2014-05-26.

The Fleischer 100

“The goal of this practical project was to design and make a hardware device that could be used to play numerous sound effects by pressing buttons and tweaking knobs and dials,” James says, and explains that he has been “taking inspiration from old cartoons of the 1930s in particular”.

The Fleischer 100

Images on the buttons complete the ‘classic cartoon era’ look

With the Fleischer 100, James has captured that era’s look and feel. Having recorded the majority of the sound effects using a Rode NT2-A microphone, he copied the sound files to a Raspberry Pi. The physical computing side of building the typewriter involved connecting the Pi to multiple buttons and switches via a breadboard. The buttons are used to play back the files, and both a toggle and a rotary switch control access to the sound effects – there are one hundred in total! James also made the costumized housing to achieve an appearance in line with the period of early cartoon animation.

The Fleischer 100

Turning the typewriter roller selects a new collection of sound effects

Regarding the design of his device, James was particularly inspired by the typewriter in the 1930s Looney Tunes short Hold Anything – and to our delight, he decided to style the final project video to match its look.

Hold Anything – Looney Tunes (HD)

Release date 1930 Directed by Hugh Harman Rudolf Ising Produced by Hugh Harman Rudolf Ising Leon Schlesinger(Associate Producer) Voices by Carman Maxwell Rochelle Hudson (both uncredited) Music by Frank Marsales Animation by Isadore Freleng Norm Blackburn Distributed by Warner Bros.

We wish we had a Fleischer 100 hidden under a desk at Pi Towers with which to score office goings-on…

The post The Fleischer 100: Pi-powered sound effects appeared first on Raspberry Pi.

App note: Application of leaded resistors in energy meters

via Dangerous Prototypes

an_vishay_leaded_resistors_on_energy_meters

App note from Vishay about energy meter circuits and the use of leaded resistors on them. Link here (PDF)

An electric meter or energy meter is a device that measures the amount of electrical energy supplied to a residence or business. It is also known as (k)Wh meter. The main unit of measurement in the electricity meter is the kilowatt-hour which is equal to the amount of energy used by a load of one kW over a period of one hour.