Miceuz of wemakethings made this Chirp, a soil moisture level sensor based on ATTINY44. When the plant dries out, it starts to chirp reminding you to water the plant: Chirp is a plant watering alarm – as simple as that. You put it into the soil near a plant and it emits a tiny chirp when the […]
Category Archives: sensors
Ford Mustang haptic feedback shift knob using OpenXC
The Haptic Feedback Shift Knob is a replacement for a manual transmission shift knob that adds haptic and visual feedback to help drivers shift appropriately. An Android application monitors the vehicle’s speed, RPM and accelerator pedal position. Based on this information, the application calculates and then indicates to the driver when he or she should […]
Using TI Chronos .NET dll with C#
The TI EZ430 Chronos watch allows for wireless transmission of button push and accelerometer events to a PC. This SourceForge project by elmariano provides a helpful example for developers of how to use the EZ430 Chronos .Net dll in conjunction with C#. It was created in Visual Studio 2010 Express, tested under 32 bit WinXP […]
TI announces sponsorship of Innovation World Cup challenge
TI has announced their participation as a sponsor in the Worldwie Innovation Cup competition: “For the fourth year in a row Texas Instruments have joined the Wearable Technologies Innovation World Cup where developers from all over the world are called to submit their innovative solutions for wearable devices. New ideas, products and prototypes can be […]
Hacking wireless radiator valves with GNU Radio
In an effort to better proportion the heating system in his house, Mike Stirling decided to use Conrad FHT8V wireless thermostatic radiator valves (TRVs) to control heat distribution in zones. He decided to analyze the valve’s 868 MHz control signals using his RTL-SDR dongle and GNU Radio. After discovering that the protocol uses simple on-off […]
Augmented guitar uses Arduino & Max MSP
Here’s a video by Thebishopgame describing how his Guitarduino works, an Arduino/MaxMSP guitar mounted midi control system: There are 6 arcade buttons on the bridge, three force sensitive resistor squares on the body, and a long FSR strip on the back of the neck. The arduino just takes sensor readings and spits them out the […]
Digital light meter using Arduino and BH1750FVI sensor
Raj writes that he’s just finished new project a digital light meter using Arduino and BH1750 sensor. The meter can display light intensity in both Lux and Footcandles: A light meter is a device that measures the intensity of light. It finds applications in schools, hospitals, production areas, passageways and more to measure and maintain […]
What is tomographic motion detection?
Recognizing the shortcomings of traditional PIR and ultrasonic sensors used in alarm systems, security researcher Connected Ape decided to explore other options. He discovered this patent for a mesh system of RF nodes, designed to detect the presence of humans based on changes in the baseline signal strength between nodes. While such commercial systems are […]
Autonomous car build
Jason Dorweiler blogged about his autonomous car build: For the localization of the car I’ll be using a GPS sensor and accelerometer. First, the GPS will find the starting coordinates of the car. Then the car will start moving, somewhat blindly at first. Once the car is moving, data from the accelerometer and elapsed time […]
Open electroencephalography
Michael Paul Coder obtained his first printed circuit board from Olimex and started with the OpenEEG project years ago, but only recently started dabbling in the measurement of brain waves while dreaming. He’s managed to build a device which can comfortably record brainwaves during sleep. He’s taken that a step further and established the Lucid […]
PC-based heart rate monitor using Arduino and Easy Pulse sensor
Raj writes that he’s just finished a new PC-based heart rate monitor using Arduino and Easy Pulse sensor (see previous Easy Pulse post). This project takes the sensor’s analog photo-plethysmography (PPG) output and feeds it into an Arduino ADC channel which converts it into digital counts which are then transferred to the PC through a […]
LeoPhi USB enabled pH interface
Ryan Edwards met up with the DP crew at Maker Faire and he sends in this post on his experiments with open source water quality sensors. For the last few years I have been creating open source water quality sensors. One of my other passions is Gardening and I had a need for pH and […]
Notacon 10 – DIY Neuroscience, EMGs, EEGs, and other recordings
In this presentation from the recent Notacon 10 conference in Cleveland, OH, Karin Halsey (aka meecie) provides a thought provoking roundup of the tech basics behind medical sensors and related devices. The talk focuses on working with basic supplies and DIY kits to measure biometric information.
TI fitness sensor guide
The new TI HealthTech fitness sensor guide provides info and application ideas on heart rate monitors, body worn fitness trackers, pulse oximeters and more. You can download your copy of the 49 page PDF from TI.
Low cost, high accuracy temperature sensing with a thermistor
Mike has written an article about using cheap thermistors as an alternative to I2C/1-wire temperature sensors: This post discusses the evaluation of a thermistor-based technique for small embedded systems capable of achieving uncalibrated temperature accuracy to rival expensive digital sensors. An experimental comparison of various sensors over temperature is then introduced.
Easy Pulse V 1.1 project update
Raj previously designed the Easy Pulse heart rate sensor. Now he informs us of an update: “I would like to inform you about the release of a new version of Easy Pulse sensor. The Easy Pulse sensor is designed for hobby and educational applications to illustrate the principle of photoplethysmography (PPG) as a non-invasive optical […]
TIDeals: eZ430-Chronos watch again
If you missed it before, TI is offering the Chronos Watch as their current week’s deal at $38 (plus shipping.) The eZ430 deal includes the wireless enabled watch, CC1111 USB RF access point, and a CD containing software and documentation. This is the watch featured in a recent post on hacking RF devices in the […]
Simple DIY ECG + pulse oximeter (V2)
Scott Harden has designed an ECG/pulse oximeter combo project using LM324 op-amps. Scott describes, “This new project is fully documented and uses extremely common and cheap parts, all of which could be purchased at RadioShack. It serves as both an ECG *and* a pulse oximeter, depending on which leads are attached. It uses a single […]
PiPurr remote cat interaction server
When the cats away, the mice will play. But…. what’s the cat doing when YOU’RE away? That question led Tris of CantHack, a group of geeks from Canterbury, UK, to develop PiPurr. Tris explains, “PiPurr is a simple client-server solution. The server runs on a Raspberry Pi, for low power consumption and provides the functionality […]
Freescale medical applications component user guide
Freescale Semiconductors has posted their Medical Applications User Guide. This 116 page PDF outlines the MCU, RF, sensor and display technologies offered with specific emphasis on their implementation in developing medical applications. Included are block diagrams of medical devices and overviews of contemporary medical electronics technologies.