Geophone – SM-24 (from Sparkfun)

Technical description: A geophone converts kinetic ground movement to voltage. Geophones work similarly to microphones, using a coil moving in the field of a magnet to generate voltage changes. A geophone can be used for geologic purposes in order to to monitor seismic activity. More on Wikipedia.  Geophones could be used for other purposes such as sensing walking activity.

Limitations: Geophones are relatively expensive, and need to be placed in a special enclosure in order to be inserted into the ground to measure seismic activity.

Skill: Advanced

Sample Sensor: Geophone – SM-24 

Sample Exercise: https://create.arduino.cc/projecthub/team-protocentral/measuring-seismic-activity-using-protocentral-openpressure-702324

Barometric Pressure Sensor – MPL115A1
(from Sparkfun)

Technical description: A microelectromechanical systems (MEMS) barometer is very small (<0.1mm) and are used to measure air pressure. They can be used to measure altitude, and are widely used in smartphones. (more on Wikipedia)

Limitations: Weather conditions will affect pressure readings, so this should be compensated for if the sensor is being used for altitude measurements. Each sensor has a limited range of measurements and may not be suited for extreme cases such as vacuums or pressurized gas environments.

Skill: Advanced (the sensor itself is very small and requires some serious SMD soldering skills, unless you use a breakout board. The sensor output requires extra research to take readings and interpret.)

Sample Sensor: Barometric Pressure Sensor – MPL115A1 https://www.sparkfun.com/products/9602

Sample Exercise: https://learn.sparkfun.com/tutorials/bmp180-barometric-pressure-sensor-hookup-/all

SST Liquid Level Sensor (from Sparkfun)

Technical description:

There are two types: point and continuous. Point level sensors can be used to determine if the liquid is above a point (returns a boolean type output). Continuous sensors can be used to monitor a body of liquid, returning a range of values.

A liquid level sensor is used to determine the level of a fluid. This information could be used to calculate the volume of liquid in a rectangular container, since the sensor gives a height.

Limitations:

Continuous level sensors can be more expensive than point level sensors. The sensor should be isolated from the rest of the circuit to prevent water damage.

Skill: Advanced

Sample Sensor: SST Liquid Level Sensor

Sample Exercise: Smart Measuring Cup 

Weather Shield

Technical Description:
The SparkFun Weather Shield is an easy-to-use Arduino shield that grants you access to barometric pressure, relative humidity, luminosity and temperature. There are also connections on this shield to optional sensors such as wind speed, direction, rain gauge and GPS for location and super accurate timing. The Weather Shield utilizes the following collection of individual sensors:

1. Si7021 humidity/temperature sensor
2. MPL3115A2 barometric pressure sensor
3. ALS-PT19 light sensor. The shield relies on the Si7021 and MPL3115A2 Arduino libraries.

Limitations:
The Weather Shield comes as a stand-alone board. Headers, connectors and additional sensors will need to be purchased separately. Also, this sensor was specifically designed for the SparkFun RedBoard and Arduino Uno and will not work with other boards without modification.

Skill:
Competent Coding Skills ⅗,  Competent Electrical Prototyping ⅗

Sensor:
SparkFun Weather Shield
https://www.sparkfun.com/products/13956

Sample Tutorial:
SparkFun Weather Shield with Arduino
https://github.com/sparkfun/Weather_Shield

Arduino Weather Shield Hookup Guide V12
https://learn.sparkfun.com/tutorials/arduino-weather-shield-hookup-guide-v12

Atmospheric Sensor

Atmospheric Sensor

Technical Description:
The SparkFun BME280 Atmospheric Sensor Breakout is the easy way to measure barometric pressure, humidity, and temperature readings all without taking up too much space. Basically, anything you need to know about atmospheric conditions you can find out from this tiny breakout. The BME280 Breakout has been design to be used in indoor/outdoor navigation, weather forecasting, home automation, and even personal health and wellness monitoring.

Limitations:
Although small and low cost, this sensor does not capture the range of environmental metrics, such as luminosity or location, that some other sensors capture. Also, the sensor does not have headers installed and will need to purchased and soldered on yourself.

Skill:
Beginner Coding Skills ⅕,  Competent Electrical Prototyping ⅗

Sensor:
BME280
https://www.sparkfun.com/products/13676

Sample Tutorial:
SparkFun BME280 Arduino Library
https://github.com/sparkfun/SparkFun_BME280_Arduino_Library

Humidity and Temperature Sensor – RHT03

Technical Description:
The RHT03 is a low cost humidity and temperature sensor with a single wire digital interface. The sensor is calibrated and doesn’t require extra components so you can immediately begin measuring relative humidity and temperature.

Limitations:
Although small and low cost, this sensor does not capture the range of environmental metrics, such as barometric pressure, that some other sensors capture.

Skill:
Beginner Coding Skills ⅕,  Competent Electrical Prototyping ⅗

Sensor:
RHT03
https://www.sparkfun.com/products/10167

Sample Tutorial:
Humidity and Temperature Sensor with Arduino
http://www.theorycircuit.com/rht03-humidity-temperature-sensor-arduino/