In this episode of Projects with Ryan Slaugh, we put a Raspberry Pi with an Alamode to work controlling a Pinewood Derby race track. The aim of this design is to assist the race managers in keeping things running smoothly as well as giving accurate information about who won and the individual race times of each car.
This project is actually an update of an older build. The original system utilized an Arduino to monitor the sensors and control the LEDs. The user needed to connect via USB to the Arduino in order to get all the data – though it could be operated in stand-alone mode as well. The update brings the power of the Raspberry Pi to give the user more flexibility in applications to run the race (both off the shelf, freeware modifiable, and custom) as well as an easier connection via ethernet or even wireless if the Pi is so equipped. The Alamode handles the high-speed sampling and the Pi serves up the information and provides user control.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
Antipasto Hardware Blog made this fun project for their fish tank! Full tutorial here.
This may or may not have implications for real-life shark tracking, but I’ll take an excuse to have my shark tweet me when he (or she, I’m no marine biologist) breaches the perimeter over to the sunny side of the tank.
Of course, I’m doing this with my toy shark-on-a-stick and only a laser level and a light sensor, but it’s possible to make this much more accurate and granular just by adding more strategically placed sensors/light sources into the mix…
As soon as the laser is obstructed by Bruce the shark himself, that light value drops. Once it’s below 400, the Android program issues a Red Alert warning that the sensor has been tripped, and sends a tweet.
This cyber-tronic looking sensor hides a secret behind it’s glimmering eye. Unlike most temperature sensors, this sensor measures infrared light bouncing off of remote objects so it can sense temperature withouthaving to touch them physically. Simply point the sensor towards what you want to measure and it will detect the temperature by absorbing IR waves emitted. Because it doesn’t have to touch the object it’s measuring, it can sense a wider range of temperatures than most digital sensors: from -70°C to +380°C! It takes the measurement over an 90-degree field of view so it can be handy for determining the average temperature of an area.
NEW PRODUCT – Melexis Contact-less Infrared Sensor – MLX90614 5V – This cyber-tronic looking sensor hides a secret behind it’s glimmering eye. Unlike most temperature sensors, this sensor measures infrared light bouncing off of remote objects so it can sense temperature without having to touch them physically. Simply point the sensor towards what you want to measure and it will detect the temperature by absorbing IR waves emitted. Because it doesn’t have to touch the object it’s measuring, it can sense a wider range of temperatures than most digital sensors: from -70°C to +380°C! It takes the measurement over an 90-degree field of view so it can be handy for determining the average temperature of an area.
This sensor comes in an easy-to-use metal can. You can easily solder it or plug it into a breadboard. The four pins are used for power, ground, i2c clock and i2c data. There are two versions, one for 3V power and logic levels and one for 5V power and logic levels. This item is the 5V version! – good for use by classic Arduinos. You’ll also want two 10K pull-up resistors for the I2C data lines, which we thoughtfully include.
A Swedish hair-care company had this simple, great idea for their ads in subway stations and they used Raspberry Pis to implement it! Via Adweek.
This fun digital subway ad in Sweden for hair-care products was rigged up to recognize when trains entered the station—and then showed a woman’s hair blowing all around, as though windswept by the train. It’s a simple, delightful effect—playful, responsive and seemingly magical in the way it erases the line between ad and environment.
Ad agency Akestam Holst and production company Stopp produced the ad for Apotek Hjärtat’s Apolosophy products. Stopp in Stockholm says the ad was scheduled to be just a one-day stunt. But Clear Channel loved it so much that they kept it live for five more days “as a way for them to show the opportunities their screens can offer.”
The ad agency explained how they made the project: “…we needed to build a device that could be calibrated to sense the arrival of the train and not react to passing passengers. Using an ultra sonic sensor, connected to a Raspberry Pi and a local network socket, we connected our device to the screens computer where the film could be activated by the passing trains.“
Tutorial: Adafruit 1-Wire Thermocouple Amplifier – MAX31850K. Thermocouples are very sensitive, requiring a good amplifier with a cold-compensation reference. So far we’ve carried the very nice MAX31855 which is an SPI interface thermocouple amplifier. The ’855 is great but if you have a lot of thermocouples to measure it isn’t terribly easy to use. That’s why we are also carrying the new ’850 model from Maxim – it’s a “1-Wire” thermocouple amp which can have any number of breakouts on a single shared I/O line.
Rice Professor Adrian Lenardic used an accelerometer to take various measurements while skateboarding at the local skate park and, unsurprisingly, the kids around him grew interested, via phys.org:
Lenardic’s return to skateboarding was still three years away when a sequence of events began that would eventually blend the sport with his profession as a scientist. “In 2005, I wrote a CAREER grant to the National Science Foundation,” he said. “The CAREER grant asks you to define research projects that might span a career, but they know that you are an educator, so they also want you to think about ways to integrate your research into the classroom.”
Lenardic’s grant enabled him to create a visualization studio that can be used not only for university research and teaching, but also by K–12 students and educators, artists, and science communicators. Part of the program involves building a computer model that simulates geologic processes such as plate tectonics, surface erosion, continental collisions and planetary cooling. Another element is the creation of a workshop where advanced undergraduate and graduate students develop hands-on demonstrations of key concepts in geoscience.
“That can be drawing a picture or building a scale model you can put on a table,” Lenardic said. He hopes the program will encourage students to see beyond artificial boundaries within subfields and gain a greater understanding of how scientific processes are interconnected.
As Lenardic continued tinkering, building things and taking measurements, he acquired equipment to collect on-the-fly data, such as an accelerometer, a Doppler radar unit and strain gauges. About two years ago, thinking about his newly reinvigorated hobby of skateboarding, Lenardic took his measuring gear to the skatepark. “As a curious and nerdy scientist, I brought the stuff out to measure myself,” he said. “I just wanted to see how efficiently I was skating.”
Some of the equipment, such as an accelerometer, was strapped to his body, while others, such as the Doppler radar unit, were set up on stands and aimed at him as he sped down the ramps or up and around the curves of the swimming pool-like bowls.
Each Tuesday is EducationTuesday here at Adafruit! Be sure to check out our posts about educators and all things STEM. Adafruit supports our educators and loves to spread the good word about educational STEM innovations!
NEW PRODUCT – Thermocouple Amplifier with 1-Wire Breakout Board – MAX31850K – Thermocouples are very sensitive, requiring a good amplifier with a cold-compensation reference. So far we’ve carried the very nice MAX31855 which is an SPI interface thermocouple amplifier. The ’855 is great but if you have a lot of thermocouples to measure it isn’t terribly easy to use. That’s why we are also carrying the new ’850 model from Maxim – it’s a “1-Wire” thermocouple amp which can have any number of breakouts on a single shared I/O line.
The MAX31850K does everything for you, and can be easily interfaced with any microcontroller that has 1-Wire support. This breakout board has the chip itself, a 3.3V regulator with 10uF bypass capacitors all assembled and tested. This board can be used with ‘parasitic power’ – where the power is on the data line – or with ‘local power’ where the power for the converter comes in on the Vin Pin.
Please note: this board does not have level shifting on the 3V Data line – we did this on purpose so that it can be used in parasitic mode. The data line must be level shifted to 3V – our 4-channel shifter works wonderfully for level shifting 1-Wire and you only need one at the ’1-Wire host’ for all thermocouples on the shared data line.
The MAX31850K data format is very similar to that of the well known 1-Wire DS18B20 temp sensor but it is not drop in compatible without code changes to check for the new ’1 Wire family’ type. We have adapted the classic Arduino OneWire and DallasTemp libraries to be MAX31850 compatible, so please click on those links to grab our libraries.
Comes with a 2 pin terminal block (for connecting to the thermocouple), 4.7K data line pullup resistor, and pin header (to plug into any breadboard or perfboard). Goes great with our 1m K-type thermocouple. Not for use with any other kind of thermocouple, K type only!
Works with any K type thermocouple
Will not work with any other kind of thermocouple other than K type
-270°C to +1370°C output in 0.25 degree increments
Internal temperature reading
3.3 to 5v power supply. Data line is 3V only
1-Wire interface allows any number of thermocouple amps on a single data line
In this tutorial I’ll show you how to construct a wireless motion sensor and interface it to a Raspberry Pi minicomputer. I’ve detailed two options that both work very well and have long lasting battery power consumption. The first option involves hacking a key fob remote that has four buttons. We will use the remote to send a signal every time the motion detector senses motion. The four buttons of the remote gives you the ability to run 4 wireless motion sensors.
The second option uses a much more sophisticated, but low cost, RF transmitter and receiver made by Ciseco. Ciseco have developed firmware that can be loaded onto the RF modules to give them different personalities (temperature sensor, button, hall affect, relay etc…). The XRF is more expensive than the key fob but it offers much better transmission distances that will penetrate walls a lot better than the key fob remote. The XRF also has the ability to send battery levels and operate different networks that give you an almost limitless amount of sensors that can be connected to the Raspberry Pi.
The pre-installed filter (also sold separately if you want to convert your own camera) allows you to take an infrared photo in the “red” channel of your camera, and a visible image in the “blue” channel. These can be used to measure photosynthetic activity; you can read more about the technique here and here.
This technique was developed by contributors to the Public Lab, an open network of collaborators who develop affordable environmental science tools. Weighing less than an ounce, it’s perfect for connecting to your laptop, a Raspberry Pi, or a mobile sensing platform, and with unscrewable lenses and no infrared-block filter, it can be adapted for other uses as well.
NEW PRODUCT – Electret Microphone Amplifier – MAX9814 with Auto Gain Control – Add an ear to your project with this well-designed electret microphone amplifier with AGC. This fully assembled and tested board comes with a 20-20KHz electret microphone soldered on. For the amplification, we use the Maxim MAX9814, a specialty chip that is designed for amplifying electret microphones in situations where the loudness of the audio isn’t predictable.
This fancy microphone amplifier module is a step above the rest, with built in automatic gain control. The AGC in the amplifier means that nearby ‘loud’ sounds will be quieted so they don’t overwhelm & ‘clip’ the amplifier, and even quiet, far-away sounds will be amplified. This amplifier is great for when you want to record or detect audio in a setting where levels change and you don’t want to have to tweak the amplifier gain all the time.
The chip at the heart of this amp is the MAX9814, and has a few options you can configure with the breakout. The default ‘max gain’ is 60dB, but can be set to 40dB or 50dB by jumpering the Gain pin to VCC or ground. You can also change the Attack/Release ratio, from the default 1:4000 to 1:2000 or 1:500. The ouput from the amp is about 2Vpp max on a 1.25V DC bias, so it can be easily used with any Analog/Digital converter that is up to 3.3V input. If you want to pipe it into a Line Input, just use a 1uF blocking capacitor in series.
Bluetooth devices are widely used in many consumers products, its the most popular wireless protocol for small point-to-point networking. Every laptop and just about every computer has Bluetooth classic built into it, so you often don’t need a data receiver for a computer. And recently, the Bluefruit product family has made it even easier to integrate Bluetooth in an Arduino project. So why not use this technology in a simple home automation project?
Bluetooth is fast, low-power, and you can communicate with Bluetooth devices directly from a computer because they usually have built-in Bluetooth capabilities. The other nice thing is that with this project, you will be able to change the sketch running on your Arduino via the Bluetooth connection, without having to plug any cables!
In this project, you will learn how to connect a Bluetooth module to Arduino, transmit measurements from a temperature & humidity sensor to your computer, and display the data in a nice Python interface. Let’s start!
NEW PRODUCT – Adafruit 9-DOF IMU Breakout – L3GD20 + LSM303 – This inertial-measurement-unit combines 2 of the best quality sensors available on the market to give you 9 axes of data: 3 axes of accelerometer data, 3 axes gyroscopic, and 3 axes magnetic (compass). We tested many different ‘combination’ sensors and found these were the best value, with stable and reliable readings.
The L3DG20 gyroscope + LSM303DLHC accelerometer/compass sensors are all on one breakout here, to save you space and money. Since all of them use I2C, you can communicate with all of them using only two wires. Most customers will be pretty happy with just the plain I2C interfacing, but we also break out the ‘data ready’ and ‘interrupt’ pins, so advanced users can interface with if they choose. A 3V regulator with reverse-polarity protection means you don’t have to worry about frying the boards by accident. There’s level shifting circuitry so the IMU can be used with 3 or 5V logic boards. And check out those mounting holes! You can securely attach this board to your rocket, robot, art project.
Each order comes with one assembled and tested 9DOF breakout board and a small piece of header.
Since this is a combination of 2 different breakouts, we suggest visiting those pages for much more information: L3GD20 and the LSM303, but here are some quick stats:
L3GD20 3-axis gyroscope: ±250, ±500, or ±2000 degree-per-second scale
LSM303 3-axis compass: ±1.3 to ±8.1 gauss magnetic field scale
This smart shirt uses textile embedded sensors making workouts trackable according to Gizmag.
French company Cityzen Sciences has won the CES 2014 Inclusive Innovation in Everyday Health award for its development of a Smart Sensing fabric woven with integral micro-sensors – these add the practical benefit of monitoring the health and fatigue levels of the wearer.
The Smart Sensing fabric reads body heat, respiration rate, heart rate, and motion through location via GPS. “The fabric can be made into any clothing; gloves, shirts, pants, you name it,” said Gilbert Reveillon, Cityzen’s international managing director.
The new smart fabric combines sensors, fabric, distributed computation, and a small battery-powered transmitter into a unit that links in real time to a smartphone. The phone runs an app that stores and analyzes data from the fabric, showing if the person wearing the garment is tired, stressed, or in the path of an imminent heart attack. Obvious applications are for people who find themselves in extreme conditions, such as athletes, first responders, and soldiers.
The shirt can perform many tasks while on the body, but there is more in store while it is off the body.
Perhaps the cleverest part of Smart Sensing fabric is still under development. Cityzen is working on a recharging system for the fabric, that receives most of its energy when the clothing is washed. This is a perfect use for a motion-driven recharging system – can you think of a better environment for collecting mechanical energy than a washing machine?