Most of internet of things solutions rely on storing data to the could. But what if you would like to build your own mini could server where you could store sensor data locally and do with it what ever you want. Dkschottt shared his simple solution to this problem where he uses bunch of tools to achieve the result. For his project he used barometric pressure sensor BMP180 and HMC5883L magnetometer that are read and data is transferred via serial interface to computer.
The rest of task is left for webserver. Since it is set up locally on computer using WAMP server tools that include Apache web server, PHP and MySQL. Data is taken from serial interface with PHP script which uses serial library. Then ti formats data in to SQL string and stores in database. HTML webpage uses simple meta refresh functionality to continuously update data. Of course there are far more better solutions but this is enough to get initial results.
VFD or other tube based indicators and clocks always look great. Akafugu has polished his IV-18 8 digit based VFD clock which also comes as kit that can be assembled without a drop of solder.
Clock is based on LPC1347 ARM Cortex -M3 microcontroller. It comes in two options, with or without GPS. The clock has all basic features you would expect including battery backup, alarm, optional GPS which is used to set time automatically, seconds can be counted with four different letter words. Project is based on open source firmware which can be hacked with your specific needs since there is plenty of memory and processing power left. Source is developed with mbed online ide and compiler.
GSM/GPRS modules can be handy solution to wireless applications where wireless network isn’t available. JOJO have written pretty extensive tutorial on how to interface and configure common SIM900 GSM module with Arduino.
GSM module interfaces to Arduino via serial interface with two wires for both direction of data flow. In order to reserve Arduino’s hardware USART for debugging and programming it is recommended to use different pins along with Software Serial Library. GSM module accepts AT commands so it is easy to program it, send SMS and even make call. Once you successfully send SMS with your desired data, you can start working on a project that sends data or alerts via GSM network.
Raspberry is great board for building internet of things stuff. It is powerful and low power to be used with small solar panel anywhere in the field. PiJuice have been working on great solar powered weather station project. It is basically a fusion of two great projects – PiJuice which takes care of solar power management and AirPi, which carries tons of sensors. The problem he run in to was the sensor board, which connects directly to Pi header, but for outside use it is better to keep electronics sealed. So he build his own version of sensor board based on same AirPi.
He used Raspberry Pi A+ for its low power consumption and for remote connection hes chosen EFCom Pro GPRS/GSM module which can send text directly to cell phone. Since most of sensors hace analog interface he used MCP3008 ADC converter which can take up to 8 analog sensors. So far there are only three sensors used – LDR, gas sensor (TGS2600) and LM35 temperature sensor. SO the list can be expanded later. Raspberry Pi communicates with GSM module via AT commands. Then python script takes care of reading sensors and sending data via serial interface to GSM module. User gets nicelly formatted text messages with all readings.