Very cool project, Jeff writes – [via]
We met Chris Jefferies a few weeks back at Maker Faire. Turns out he is using our small solar panels to do something we’ve been interested in for a while. Chris is building wireless sensor networks using open source software and hardware that could be used in a variety of applications like air quality or home energy monitoring. It looks like he was inspired by Tweetawatt and is using xBee and ASUS wifi for communication in conjunction with Pachube for data display.
Solar Powered Wireless Sensor Networks - [Link]
Deepak from Mindfront.net acquired a PIR alarm sensor module which transmitted a digital code over 433 MHz RF to signal an alarm receiver. The problem: he didn’t have the factory receiver. So he set out to sniff the transmitted RF signal using a RCR-433-AS receiver module with the data out fed into an oscilloscope. This allowed him to monitor the digital coded signal pattern and decode it into individual bits.
Hacking a PIR RF signal with PIC 12F683 – [Link]
Drone writes: This is a single part MEMS 10-DOF IMU part that will ship around 15 July 2011. OK, here’s the catch: Unless I’m missing something obvious, it looks like this device costs $605 USD each in quantity 100-499 (no, I did not forget a decimal point). There’s an EV board, but Gawd only knows what that’s going to cost.
ADIS16407: Ten Degrees of Freedom Inertial Sensor
Analog Devices, Inc. (ADI) released for general availability today the ADIS16407 iSensor IMU (inertial measurement unit) which integrates a tri-axis gyroscope, tri-axis accelerometer, tri-axis magnetometer and a pressure sensor into a single package.
ADIS16407: Ten degrees of freedom inertial sensor – [Link]
Unitronic is planning to present a wireless solar-powered sensor module for the continuous monitoring of carbon monoxide (CO) concentration in buildings and in industrial applications at the upcoming SENSOR+TEST 2011 in Nuremberg, Germany.
The core of the Unitronic Solar CO Sensor Module (USCSM) is an innovative electrochemical carbon monoxide sensor with a standard AA battery form factor, developed by Figaro, which meets the specifications of EN 50291 and VDI 2053, and a STM 300 programmable, bidirectional wireless sensor module for 315/868 MHz from EnOcean. [via]
Wireless solar-powered sensor monitors carbon monoxide levels - [Link]
A thermistor is a thermal resistor – a resistor that changes its resistance with temperature. Technically, all resistors are thermistors – their resistance changes slightly with temperature – but the change is usually very very small and difficult to measure. Thermistors are made so that the resistance changes drastically with temperature so that it can be 100 ohms or more of change per degree! [via]
Sensor tutorials – Thermistor – [Link]
Humidity sensors measure the relative humidity of air. They come in different types – both digital and analog types. The digital types are relatively more expensive than the analog types. The measured relative humidity by digital humidity sensors are commonly sent out using digital serial interfaces like I2C and SPI. Analog humidity sensors are cheaper and they come in two types – capacitive and resistive humidity sensors.
Using Analog Humidity Sensors – [Link]
This project is one of many others I had made to control my house with rules, web interface, logger and many more. This project could take several measurements: Temperature/Humidity/Barometric pressure measurements. All measurements are taken digitally and have their own dedicated A/D converter in each sensor. It’s a REAL digital environment sensor WITHOUT any calibration.
Digital Temperature, Humidity, Barometric Pressure Sensor – [Link]
Another article that might help with bench power supply designs:
Current-Sense Amplifiers with Digital Output and 60V Common-Mode Range
- Offers easy interface with microcontrollers (supports 1.8V logic) by using digital outputs
- Delivers wide 60V common-mode range for robustness under fault conditions
- Includes internal op amp/comparator that allows flexibility in system design: the internal amplifier can be used to limit the inrush current or to create a current-source in a closed loop system; the comparator can be used to monitor fault events for fast response
High-side, current-sense amplifiers with 12-bit ADC and op amp/comparator - [Link]
This project shows the user of a simple thermistor to measure temperature and display the temperature graphically on a Nokia 3310 LCD. Thermistors are incredibly cheap (about 50 cents), and provide fraction of a degree accuracy. The Nokia 3310 Library originally written by CC Darmini was modified yet again, this time to use per pixel access while maintaining the ability to draw text.
AVR Based Digital Thermometer with Nokia 3310 LCD and Thermistor - [Link]