Sensing the Environment

A large part of any environmental project is observing and monitoring environmental changes. For scientific studies this might include a variety of monitoring types such as temperature gradients over a wide area; for agriculture, this may include rainfall and soil moisture; for poultry farming, this may include monitoring temperature within incubators or temperature in coops/laying houses. Groundwater applications may have well-related data being recorded, such as depth and water quality. Stream-related projects often need water quality, temperature, and flow rate to be monitored. myObservatory is designed with these needs in mind.

Commercial Sensor Equipment

Any commercial sensor that can export its data to a CSV (Comma-Separated Values) format file can be used with myObservatory. Using our innovative Guided Upload tool, you will be taken through a quick upload process step by step to bring in your sensor data.

YSI incorporated - Water Quality Sonde

Arduino Sensors

Arduino is a powerful electronics prototyping platform that is open source, well documented, and has a vibrant community around it. Arduino microcontrollers are inexpensive and easy to use, so they make a great base to build custom sensor devices. As a proof of concept, we have developed two Arduino-based environmental sensors, and integrated them into myObservatory. You are welcome to use our designs to make your own customized sensors for use with myObservatory. We do not officially support or sell these Arduino sensors, but we will be happy to provide hints, tips, and point you in the right direction. This can be an excellent approach to getting good sensor coverage at your institution, and has potential for educational initiatives like sensor-building workshops.

Cellular-Based Temperature Sensor

Our first example uses two DS18B20 digital temperature sensors, and uploads the readings taken via a cellular modem directly to myObservatory. This device uses an Arduino Uno, an Arduino GSM Shield, and a SainSmart LCD 1602 Keypad Shield for the device itself, and two DS18B20 temperature sensors. (A "shield" is a preassembled stackable module for use with Arduino.)

The Arduino source code for this sensor may be seen here, and the prototype user's guide may be downloaded here. See below for a basic wiring diagram.

SD-Card Based Multi-Sensor

Our second example forgoes the immediate cellular upload to achieve higher battery life. In this model, we remove the GSM modem and LCD shield, and instead use a combined Joystick plus TFT Display plus microSD card shield. This unit also expands on the sensors, using one DS18B20 digital temperature sensor, a simple soil moisture sensor, and a DHT22 combined air temperature and air humidity sensor.

This again uses an Arduino Uno, and also uses an Adafruit TFT/microSD/Joystick shield. Our sensors include the familiar DS18B20 temperature sensor, and a DHT22 temperature/humidity sensor, as well as a generic soil moisture sensor. Lastly, since we have no instant upload via cellular, we need to know the time so we can record it on the SD card. This is accomplished with a DS1307 Real-Time Clock. In order to further reduce power draw, this example also provides power to the external sensors via a digitally controlled MOSFET, so some additional resistors, capacitors, and a generic MOSFET or transistor are needed. The general idea of this sensor is outlined below:

The source code for the SD-card example sensor may be seen here. Some additional Arduino libraries that may be useful with this code have been assembled for convenience here.