Tag Archives: sensors

DIY Connected objects for happy connected people

via Arduino Blog


What happens when a creative technologist wants his family to know he’s thinking about them? He creates a project with Arduino Yún! IMissYou is a simple project transforming a picture in a connected object thanks to a capacitive layer made with Bareconductive Paint and inserted behind the photo. The ‘touch’ is detected by the Arduino through the glass of the frame by a spike in the values (with a basic Capsense library), sent to the internet via wi-fi and delivered to a phone with Pushover.


Martin Hollywood, the Arduino user who made  the project, wrote us:

Looking at the photograph of my family that I have on my desk one day, I missed them and wanted to be home. I touched the photo and realised that somewhere between those was the germ of the idea…

I wanted my family to know I was thinking of them, but I didn’t want to create two products; think GoodNight Lamp – I do love that project. In any case, there was no guarantee they would even notice a ‘blinking’ photo frame responding to my signal. Making the Receive a PUSH notification seemed like a no brainer, but the last time I developed for mobile was iOS 1! There are a number of service apps out there: Pusher, Pushingbox but I decided on Pushover. It had a 7 day trial period and good API support (I’ve since bought a license).

Take a look at his blog for more details and if you want to give him some tips to make it a real product.

Buy the Sense HAT – as seen in space*!

via Raspberry Pi

*Not actually in space yet. Wait till December.

Today we have a new product launch: the Sense HAT is now available from the Swag Store, and through our partners RS Components and Premier Farnell/CPC. Here’s a video from Matt Timmons-Brown, freshly released from GCSE exam hell, to show you around.

The Sense HAT was originally developed around James Adams’ idea to make a cool toy-style board that showed off just how much you could do with your average modern MEMS gyroscope, 64 RGB LEDs and some Atmel microcontroller hackery.

Somewhere between prototype and production, it seems to have attracted extra features like a pressure sensor, a humidity/temperature sensor and a teeny joystick. It also seems to have been comandeered and made an integral part of the Astro Pi mission, which will see two Raspberry Pis, two Sense HATs and a lot of code written by UK schoolkids hosted on the International Space Station – I guess I’m to blame for that.

Astro Pi sense HAT LED

The board forms the basis for many of the experiment sequences that will be run on the ISS – many of the schools competition winners’ entries made good use of the HAT’s sensors to gather their experimental data. The LED matrix also provides a feedback mechanism and interactivity for Major Tim Peake when he’s tasked with deploying the Astro-Pi board on the ISS (he’ll be setting it up on-orbit to run the experiment sequences). One of the winning entries – Reaction Games – programmed a whole suite of joypad-operated games played via the LED matrix. Snake is hilarious on an 8×8 screen.

The board itself has a suite of sensors, a “D-pad” style 5-button joystick and an 8×8 RGB LED matrix driven by a combination of an LED driver chip and an Atmel AVR microcontroller – an ATTiny88.

For the terminally curious, here are the schematics of the board.

The Sense HAT and its Pi tucked snugly in the Astro Pi flight case

The Sense HAT and its Pi tucked snugly into the Astro Pi flight case

Here’s the hardware run-down:

Sensing elements:

Pressure / Temperature
ST Micro LPS25H
– 24-bit pressure measurement resolution (260hPa to 1260hPa)
– 16-bit temperature measurement resolution (0-125°C)

Humidity / Temperature
ST Micro HTS221
– 16-bit humidity measurement resolution (0-100% relative humidity)
– 16-bit temperature measurement resolution (0-60°C)

Acceleration/Gyroscope/Magnetic field
ST Micro LSM9DS1
– 9 degrees of freedom (X, Y, Z independent axes for all sensors)
– ±16 g acceleration measurement range
– ±16 gauss magnetometer measurement range
– ±2000 dps (degrees per second) gyroscope measurement range
Each of these measurement channels has 16 bits of resolution.

All of these sensors have features for periodic sampling of sensor values – complete with internal FIFO storage. The LPS25H and HTS221 have maximum sample rates of 25 per second, the LSM9DS1 has a maximum sample rate of 952Hz – we are already imagining the birth of a million Pi-controlled stunt quadcopters.

LED Matrix
The LED matrix is driven by a combination of a constant-current LED driver and an Atmel ATTiny88 running a custom firmware that delivers an 8×8 display with 15-bit resolution RGB colour. If you want to get into the gory details, the AVR firmware is available on Github.

The Atmel is responsible for sampling the joystick. We didn’t have enough pins left on the Atmel to dedicate the five that we needed to sample the joystick axes independently, so they’ve been spliced into the LED matrix row selects. The joystick gets updated at approximately 80Hz, which is the scan rate of the LED matrix.

All of the sensors (and the base firmware for the Atmel) are accessible from the Pi over I2C. As a fun bonus mode, the SPI peripheral on the Atmel has been hooked up to the Pi’s SPI interface – you can reprogram your HAT in the field! We use this method to get the firmware into the Atmel during production test – and we leave it unprotected so you can substitute the stock firmware to get it to do whatever you want. Seriously. First person to turn this sensor HAT into a quadcopter controller HAT wins a cookie from me.

If you’re not assembly-language inclined, you can always use the HAT’s sensors from our shipped Python library – standard function calls return sensor values, give you joystick key events and allow you to display things on the LED matrix. The Sense API is available through the Raspbian APT repositories.

To access the magic, simply enter:

sudo apt-get update
sudo apt-get install sense-hat
sudo pip-3.2 install pillow

into a terminal window. Note you will have to reboot for the Sense HAT to be recognised.

The API is well-documented (and tested extensively by schoolchildren as part of Astro-Pi) – get reading here.

The LED matrix appears as a Linux framebuffer device – for fun you can compare the results of

cat /dev/urandom > /dev/fb0


cat /dev/urandom > /dev/fb1

to fill either your attached monitor or the LED matrix with random noise. The joypad appears as a standard input device – the “keys” map to Up/Down/Left/Right and Enter.

The baseline price (excluding spacers and screws, and local taxes) is $30. You’ll be able to buy from all the usual suspects – the Swag Store (which is bundling spacers and screws for free), RS Components/Allied, Premier Farnell/Newark and all their subsidiaries have stock today. Secondary suppliers may take a couple of days to get their hands on stock.

So, what are you waiting for? Get sensor hacking!

The post Buy the Sense HAT – as seen in space*! appeared first on Raspberry Pi.

Testing the Shinyei PPD42NS

via Dangerous Prototypes


From the comments on our Arduino dust sensor post,  KH writes:

The sensor can obviously measure dust concentrations, it also has to be placed and set up properly, and it gives useful readings. For hobby users like most of us, obviously calibration to specific or absolute standards will be almost impossible.

More details at Darell Tan’s blog.

Via the comments. Thanks KH!



TinySensor server

via Dangerous Prototypes


Steve’s TinySensor server project, that is available at Github:

Well after almost a year I decided it was time to update this project with improvements to both its hardware and software.
On the hardware side, the server is still the original Raspberry Pi model B, but I’ve mounted the nRF24L01+ radio on a neat little Slice of Pi board. (These boards also have traces for mounting XBees with their unusual pin spacing. And they’re cheap!)

Project details at Bits on a Board blog.

Open Source Hardware Camp 2014


Open Source Hardware Camp will take place in the Pennine town of Hebden Bridge. For the second year running it is being hosted as part of the technology festival, Wuthering Bytes. However, this year OSHCamp will have the Waterfront Hall to itself on the Saturday and Sunday, with a separate Festival Day taking place on the Friday and with talks on a broader selection of technical topics.

Details of the OSHUG talks and workshops can be found below and the Wuthering Bytes website will be updated in due course with details of the complete programme of events.

Note that socials are planned for both the Friday and Saturday evenings, with the former being hosted at the Town Hall and where there will be a bar, food available and music and a live performance, and the latter will be hosted at a local hostelry that serves food.

Hebden Bridge is approximately 1 hour by rail from Leeds and Manchester. Budget accommodation is available at the Hebden Bridge Hostel, with private rooms available and discounts for group bookings. Details of other local accommodation can be found at www.hebdenbridge.co.uk.

Any questions should be directed to the Discussion List.

Saturday :: Talks

Linux bootloaders and kernel configuration

Linux is popular in embedded devices, but most use it once the kernel has booted and don't consider how it was started. This talk explores just what happens when you first start an embedded device that is running Linux, and will look at common bootloaders, such as U-Boot, along with kernel boot options. Finally, we will look at useful kernel configuration options for embedded devices.

Melanie Rhianna Lewis started a life long love of electronics as a child when her Dad helped her make a "crystal" radio with an ear piece, a coil of wire, a diode and a radiator! At the same time the home computer revolution started and she would lust after the "build your own computers" advertised in the electronics magazines of the time. She never got one but did end up the proud owner of a BBC Micro. Melanie learnt everything she could about the machine and including assembler, operating systems, drivers, interrupt, and, thanks to the circuit diagram in the Advanced User Guide, digital electronics. After the BBC Micro came the Acorn Archimedes and so started a long relationship with ARM processors. In the 90s Melanie became interested in Linux and then developed one of the first ARM Linux distributions running on an Acorn RISC PC. The hobby became a job and Melanie currently works for an embedded device consultancy near Bradford where a lot of her work is still with ARM processors. Recently Melanie became a sporty person and now spends a lot of her time hitting girls. She will probably bore you with tales of roller derby!

Open source archaeological geophysics - is it achievable?

The advance of technology into Archaeology has allowed geophysical surveys to "peer into the ground" and direct the diggers to the most likely "targets". However, as anyone whose watched Time Team will know, using Resistivity and Magnetometry doesn't always guarantee results. Such equipment is not usually within the financial reach of most hobbyists. However, the recent explosion of the Arduino, Pi and other cheap electronics has meant making such surveying equipment may be possible.

A small research project involving an informal collaboration between members of the Derbyshire Archaeological Society (DAS) & Derby Makers is exploring whether a high accuracy GPS unit, Magnetometer and a resistivity probe can be made and yield worthwhile results within a budget of £1,000. DAS has kindly funded this research and we are about 50% of the way through the GPS project. This talk will introduce the project and take a look at progress to date.

Tony Brookes was firstly an engineer and then worked in IT for a while (!) Now working part-time, hobbies easily fill the time available. Drawn to archaeological and historical research by way of Time Team, he now tries to apply open source software (Scribus, Inkscape, Qgis) and hardware (Arduino, et al) to investigating parish history and other interesting topics.

An open source aquaponics control system

Aquaponics is a closed system of food production that farms fish alongside vegetables, and this talk will look at the development of an open source aquaponics control system for the Incredible AquaGarden project in Todmorden, highlighting certain features of the design and exploring some of the difficulties encountered and how these have been addressed.

A control and monitoring system with an event-driven 'flowchart' interface will be presented, where data about aspects such as pH, temperature and light level etc. are collected and logged in order to monitor the environment. The system responds dynamically to control the level of water in the plant growing bed, to maximise the yield. Some design decisions and technical aspects of the system will be demonstrated and discussed, together with the open source model for sustaining the project.

Finally, we will look at the operational Node-RED installation in Todmorden, showing how the system is collecting readings and controlling the water level, and we'll talk about how MQTT has been used to loosely couple the code running on the Arduino with Node-RED on a Raspberry Pi.

Gareth Coleman is a inventive hardware hacker who's talent lies in connecting diverse devices. Dr Naomi Rosenberg is a freelance software developer with a background in formal logic who works on a wide variety of platforms. They both get a especially enthusiastic about open hardware, free software and empowering humans.

From Idea to Finished Product: A Tale of DFM and CEM

With numerous easily accessible embedded platforms around and concepts such as rapid prototyping and crowdfunding now being useful things as opposed to just buzzwords, designing the Next Big Thing without leaving your study is becoming a common story for makers and tinkerers.

While it is true that going from an idea to a finished product has never been easier thanks to the abundance of design resources and affordable manufacturing services, designing for volume manufacturing requires a different mindset that usually does not apply to casual weekend hacks. From component choice to packaging and logistics, there are several elements that needs to be taken into consideration, as they may cause significant headaches otherwise.

This talk will provide an overview of electronics manufacturing process, covering details such as managing design data, handling dependencies, component and process choices, testing and certification and several other aspects of DFM: Design for Manufacturability.

Omer Kilic is an Embedded Systems hacker who likes tinkering, a lot. He also likes tiny computers, things that just work and good beer.

Driving milling machines with Linux

Driving a milling machine with Linux is fairly easy and LinuxCNC (previously known as “EMC”) even provides a real-time distribution install disk. However, driving the machine is only half the story and gcode generation is at least as important.

This talk will share experiences using a mill and a router with Linux, looking at PCB manufacture, engraving, 3D milling, casting, tool paths, materials, tools and parametric design.

Matt Venn has run hundreds of creative science workshops for thousands of children and adults around the world. For the last year, he has been working with teachers in preparation for the computer science curriculum changes; creating and leading courses, workshops and projects.

When he's not inventing new ways of getting people excited about science, Matt plays music, invents puzzle boxes, practices martial arts and maintains bikes.

Oxford Flood Network - easier to Apologise Than to Ask Permission

Oxford Flood Network is a citizen sensing project which monitors water levels around the city, in streams, rivers and even under floorboards, sending water levels back to the Internet using low-powered wireless.

The network explores the possibilities of a smart city that is created by its citizens, rather than a more typical top-down deployment. Sensor networks are generally used to collect data about us for reasons and agendas chosen by others, but we can build sensor networks too; crowd-sourced data can be gathered for your agenda — providing evidence for your issues.

In this talk we will hear how Oxford Flood Network has developed an open source model for hardware and software, and the challenges of sticking mysterious boxes under bridges.

Ben Ward is founder of Love Hz, promoting the use of white space spectrum for open innovation in the Internet of Things. A survivor of the dotcom bubble, subsea bandwidth glut and the UK broadband wars, he's still surprisingly optimistic about the future.

An introduction to writing applications for the Parallella board

Parallella is a credit card-sized computer with a many-core accelerator that allows it to achieve high floating-point performance while consuming only a few watts. In this talk we will take a look at the Epiphany architecture and how to use the eSDK to write highly parallel applications for it, using hardware and software features to benchmark code and optimise performance.

Simon Cook leads Embecosm's work on LLVM and is author of the standard guide to the LLVM assembler. He is also an expert on low-energy compilation and is lead engineer on the MAGEEC project. Simon holds a double first class honors degree in Computer Science and Electronics from Bristol University.

Radio Then and Pararchive: decentralised, pervasive, and open story telling

Radio Then is a citywide cultural history experience, telling stories about Manchester’s jazz and popular music heritage using a small, Arduino-powered radio. Participants explore the city and tune in to archival broadcasts related to places, people, and events of note. In actual fact, the ‘radio’ contains GPS and audio breakouts to track its location and cue audio tracks depending on its coordinates.

The project is being created to showcase findings from Pararchive, an AHRC project being conducted by the University of Leeds, in partnership with the BBC, National Media Museum, Science Museum Group, and Manchester Digital Laboratory, among others. Pararchive represents an opportunity for members of the public to engage with archives, decentralising the material from archive holders, and offering alternative and personal perspectives on events.

James Medd is an artist, musician, and maker based in Manchester. He teaches all things digital in the north west of the UK, and creates whimsical, entertaining, and accessible interactive artworks. He currently leads Arduino Manchester, a community group for Arduino users in Manchester, and will be developing more interactive audio experiences at Watershed’s Pervasive Media Studio later this year, as a winner of their graduate and new talent competition.

Commercialising your ideas

Whether you're taking the time to build something fun, or have a solution to a problem you have faced, you are 'in your own right' an inventor.

One of the biggest challenges inventors face isn't making their product work, it's generating a living to continue inventing. Having spent over a decade in both sales and business development I have witnessed people use various methods to overcome this hurdle. I hope to share with you some of my experiences to provide you with some ideas you can take away and use when looking to turn a hobby or bright idea into a financial success. Our topic of conversation will take us from having a light bulb moment, to securing orders and reaping the rewards.

William Stone is the Head of Channel Strategy for hardware manufacturer, Ciseco. He is responsible for various commercial areas of the business including the very familiar responsibility of growing Ciseco's rapidly expanding chain of partners and distributors. Now with 36 recognized distributors worldwide, Ciseco has a growing presence and reputation in electronics manufacturing and Internet of Things (IoT).

OpenTRV: energy technology that saves householders money

The OpenTRV project aims to provide software, hardware designs and excellent interoperability to allow UK and EU householders to as much as halve their heating bills and carbon footprint with simple to fit hardware costing around £100 per house. Everything is freely available under liberal licensing — even our 3D printed enclosures — to enable adoption and cost savings.

Damon Hart-Davis gets excited about electronics, parallelism, robotics, distributed systems and resource efficiency, and solar PV and halving space-heating carbon footprint with cheap microcontrollers (OpenTRV) are two of his current passions. Damon has been working on “mission-critical” systems in banking for most of the last 20 years and before that founded one of the first UK Internet Service Providers.

Interfacing with SPI and I2C

SPI and I2C are industry standard methods of interfacing IO devices to micro-controllers and CPUs using just a few connections. SPI requires four wires and I2C just two.

This talk introduces SPI and I2C. It describes how they work and how you use them. It will look at common IO devices that connect via SPI or I2C. Finally it will look at controlling SPI and I2C devices from two example controllers, the Arduino and the Raspberry PI, in languages such as C and Python.

Speaker: Melanie Rhianna Lewis.

Introduction to Baserock

Baserock is a new set of open source tools for creating "appliance" operating system images. The aim is to close the gap between source code repositories and the code running on a device. This talk will go over Baserock's philosophy, what it provides and how you can try it out today.

Sam Thursfield likes it when technology is surprising in a good way but does not like it when it is surprising in a bad way. He spends a lot of time trying to reduce the amount of code that is required to do things. He has been known to play the trombone in and around Manchester.

Concurrency in the real world with xCORE and XC

There are many cases where a simple microcontroller won't cut it and the FPGA design route may be too drawn out and costly, particularly if your background is in software.

With the XMOS multi-core microcontroller architecture and toolset it's now possible to tackle complex hardware problems using familiar software and algorithms, avoiding the need to work with Verilog or VHDL. The XMOS XS1 microcontrollers provide tens of nano second resolution and deterministic, predictable, real-time operation in software. The XMOS toolset enables designs to be simulated and analysed, and signals to be monitored and scoped all within the IDE.

The XC extensions to C provide simple interfaces and tasks to write concurrent programs, taking care of nasty race conditions and parallel usage errors. xCORE open source libraries help break down complex domain-specific tasks, allowing you to focus on developing applications. While XMOS Links enable microcontrollers and boards to be chained together in a divide and conquer manner, allowing you to orchestrate your own hardware solutions.

This talk will introduce the XMOS technology and explore a selection of real world applications.

Alan Wood has been working with concurrent and distributed programming for over a decade. His recent work includes smart grid, control, and motion systems based on XMOS' concurrent technology. He is a long term advocate and moderator (aka Folknology) for xCORE and other SHW communities, such as TVRRUG, as well as a founder of hackspace, SHH.

Compered by:

Paul Tanner is a consultant, developer and maker in wood, metal, plastic, electronics and software. His day job is IT-based business improvement for SMEs. By night he turns energy nut, creating tools to optimise energy use. Paul graduated in electronics and was responsible for hardware and software product development and customer services in several product and service start-ups, switching to consulting in 2000.

Sunday :: Workshops

Some workshops will provide tools, boards and components etc. However, subject to demand this may involve an element of sharing and please feel free to bring along equipment and components, but note that you must be able to take full responsibility for your own personal safety and that of others in respect to these. Common sense must be exercised!

Let's build a flood network for Hebden Bridge!

Split into two teams, one will attempt to install flood sensors on the beautiful Hebden Water just outside the venue, while the other links these these to the Internet using readily available technology.

Proven hardware designs will be used to show you how can send water levels back to the Internet using low-powered wireless links, and sustainable approaches to citizen sensing will be explored.

Run by: Ben Ward.

Workshop notes: you may want to bring wellies if you plan to join the sensor installation team! Also feel free to bring sensors and boards that you think may be useful.

Building applications that sense and respond to the real world

Following on from their talk, Naomi and Gareth will be joined by Paulo Marini, the Tormorden project's resident aquaponicist. Together they will facilitate a hack session to help you build applications that respond to the real world.

Run by: Gareth Coleman and Dr Naomi Rosenberg.

Workshop notes: Bring your own hardware to work on, such as Raspberry Pi and Arduino etc. if you can, and they'll try to find ways to get your projects connected.

Do you want to build a robot? #meArm assembly workshop

How about starting with an Arm? With just a screwdriver and enthusiasm you can build an Open Source Robot Arm. If you bring an Arduino or Pi with you, you're free to stay on with your meArm and tinker with the code too.

The meArm is a project to get low cost robot arms into the hands of as many people as possible. Started in February this year it's made fast progress through open development. Already "home brew" (those not from the laser forges of phenoptix in Nottingham) versions have been spotted in the UK, Switzerland, the USA and Mexico!

Ben Gray is a proponent of Open Hardware and founder of phenoptix, a maker business based in Beeston, Nottinghamshire. Ben graduated from the University of Exeter with a chemistry degree and a fledgling phenoptix before moving to Nottingham to complete a PhD in theoretical physical chemistry. Through the open hardware movement he has been able explore the wonderful world of electronics and take phenoptix from a pocket money project to the full time job it is today.

Workshop notes: Bring along a laptop and, if you like, an Arduino or Raspberry Pi.

Introduction to Bus Pirate

The Bus Pirate is a universal open source hardware device that can be used to communicate using various buses, such as SPI, I2C, UART and JTAG, with various devices. The Bus Pirate is, per the designers, intended to "Eliminate a ton of early prototyping effort with new or unknown chips."

This tutorial will introduce the Bus Pirate. Describe how to configure it and install the software required to use it. It will then look at some basic interfacing to devices via SPI and I2C. It will work through how you can 'sniff' buses. Finally it will look at use the Bus Pirate as a simple frequency measurement and generator device.

Run by: Melanie Rhianna Lewis.

Workshop notes: bring along a laptop (Bus Pirate is supported under Windows, Linux and OSX) and, if you can, some hardware to debug. There will be a limited number of Bus Pirates available, but if you have one please bring it along.

Building your first Parallella application

This workshop follows on from the previous day's talk and participants will build a simple project which targets the Parallella board and uses all 16 cores of the Epiphany floating-point accelerator.

Run by: Simon Cook.

Workshop notes: Please bring along a laptop and, if you have one, a Parallella board (a limited number of boards will be available for use by those who do not own one).

The real world works concurrently and so can you

This workshop will take you through the basics of embedded concurrent programming using an XMOS multi-core startKIT. We will cover basic parallel processing extensions to C (XC) using tasks, interfaces, timers and ports. We will also get some insight into our running code using xSCOPE, a real-time debugging system built in to the XMOS tools. In addition we will use software modules to drop in rich functionality from the open source xCORE libraries.

Run by: Alan Wood.

Workshop notes: bring along a laptop and any devices you would like to interface.

Design a PCB Shrimp and have it fabricated

The Shrimp is a super low cost Arduino clone. It makes an excellent teaching resource, and is usually delivered as a 'breaded shrimp' - using a breadboard. For hackers, it's a great way to knock up a quick, cheap microcontroller circuit.

In this workshop we'll make a PCB version of the shrimp — a more robust and Arduino shield compatible version — and you will be guided through the process of drawing the schematic, laying out the PCB and optionally placing an order with OSHPark for your very own PCB shrimp.

Participants will be working in pairs. Boards will cost about £6 each. Kits of components can conveniently be ordered from shrimping.it for £4.

Run by: Matt Venn.

Workshop notes: bring along a laptop.

OpenTRV build and getting started

Kits will be available to solder and boards and cables to buy, along with valves that will be used to demonstrate how you can use Arduino-based technology to halve your heating bill.

Run by: Damon Hart-Davis.

Workshop notes: Please bring your own soldering iron, solder and AA batteries if you would like to build a kit to take away, and be aware that SMD soldering experience and a steady hand will be required to solder the TMP112 temperature sensor.


  • There are separate tickets for Friday, Saturday and Sunday.
  • A light lunch and refreshments will be provided each day.
  • Please aim to arrive between 09:00 and 09:15 on the Saturday as the event will start at 09:20 prompt.