Secure your project with biometrics - this all-in-one optical fingerprint sensor will make adding fingerprint detection and verification super simple. These modules are typically used in safes - there's a high powered DSP chip that does the image rendering, calculation, feature-finding and searching. Connect to any microcontroller or system with TTL serial, and send packets of data to take photos, detect prints, hash and search.
In this tutorial we'll be showing how to utilize a DHT sensor Python library based on C for high-speed GPIO polling to handle bit-banged sensor output. Many low cost sensors have unusual output formats, and in this case, a "Manchester-esque" output that is not SPI, I2C or 1-Wire compatible must be polled continuously by the Pi to decode. Luckily, the C GPIO libraries are fast enough to decode the output.
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! This guide will teach you how thermistors work, and how to wire them up and use them with your favorite microcontroller.
Tilt sensors allow you to detect orientation or inclination. They are small, inexpensive, low-power and easy-to-use. If used properly, they will not wear out. Their simplicitiy makes them popular for toys, gadgets and appliances. This guide will show you how they work, show you how to wire them up, and give you some project ideas.
IR detectors are little microchips with a photocell that are tuned to listen to infrared light. They are almost always used for remote control detection - every TV and DVD player has one of these in the front to listen for the IR signal from the clicker. In this guide we will explain how IR sensors work, how to pull IR codes out of a remote control, and show you how to wire them up to a microcontroller.
The TSL2561 luminosity sensor is an advanced digital light sensor, ideal for use in a wide range of light situations. Compared to low cost CdS cells, this sensor is more precise, allowing for exact lux calculations and can be configured for different gain/timing ranges to detect light ranges from up to 0.1 - 40,000+ Lux on the fly. This guide will show you how this sensor works, and how to use it with your favorite microcontroller.
The combination of connecting a Raspberry Pi to COSM makes creating a internet of things much easier than it has been in the passed. The Pi with it's easy access to ethernet and COSM's drop dead simple usability will graph all sensor data you send to it. This tutorial explains how to connect a analog temperature sensor to the Pi and use a small python script to upload that data for storage and graphing on COSM.