Weather Station Extensions
Designed by Mark Little
The purpose of this project is to extend the range of readings provided by the home weather station. It is quicker to obtain the standard readings by simply purchasing a commercial home weather station and setting it up. It is really only cost effective to make the more unusual sensors that you want to connect to the Internet.
In the case of this project, this includes ground thermometers (0cm, 10cm, 20cm, 50cm and 90cm deep), pool thermometers (0cm, 10cm, 20cm, 50cm and 90cm deep), ground moisture sensor, gas air quality measurements, and leaf wetness.
Once there is a weather station framework, just for the challenge, it is easy to add some additional old sensors, In this case, they included an old tipping bucket rain gauge, a Geiger Counter kit and a cheap combined temperature/humidity sensor.
Since this is just a hobby activity using sensors that "were just laying around", one of the project's objectives was to keep costs down.
As a result, it was decided to use a cheap Arduino UNO from the Internet as the primary computer to drive the sensors. Versions of these boards can be found on the Internet for a few dollars and there are extensive libraries and development tools available free of charge.
While the UNO is cheap and easy to program, it lacks the computing resources to take the readings it makes and store them in a database, then send them to the Internet. This part of the project is accomplished by connecting the Arduino to another computer that does the database and Internet processing.
There are three options for this task. In phase 1 of the project this task falls to the home server which is a Linux computer running a MySQL database and with a permanent connection to the Internet.
Phase 2 of the project has ported that software onto a Raspberry Pi connected to the home network. This allows the Arduino to speak to a computer out in the shed in the backyard where the observations can e monitored and recorded to a database before being processed for display on the Internet..
The System Button below links to an overview from reading gathered from the sensors by the Arduino, as well as the database and Internet communications software on the Linux computer.
Phase 3 will probably replace the Arduino's USB Serial connection to the host computer with a Wi-Fi link. This phase would be used in conjunction with a solar panel and battery to provide stand-alone power for the Arduino. The system could then be installed in the best place for measurements, rather than where power and communications can reach.