3. Sensors
A sensor is a device designed to measure some physical quantity in its environment. An example might be a heat sensor that measures the temperature in a room or a pressure sensitive mat that detects someone walking over it.
A temperature sensor is tucked away somewhere inside this fridge and its output is used by the display you see. The output could as easily be fed into a computer for further processing. |
Once they have taken a reading or measurement, they might send that reading straight back to the computer or they may store it up and take a set of readings over time and send them back in a batch.
This data is called an ‘input’. Whilst the sensor itself is producing an 'output'.
There are many different types of sensors, below is a table showing you a few of the most common ones:
Sensor | Measures | Where Used |
---|---|---|
Heat | Temperature | Living room for central heating system |
Humidity | Water vapour in the air | Swimming pool, greenhouse |
Infra-red | Infra-red radiation e.g. body heat | Security alarm systems |
Light | Light levels | External security lights |
PH | Acid/alkali levels e.g. pH of soil | Environmental experiments, river pollution |
Pressure | Pressure | Burglar alarm systems, automatic doors |
Smoke | Smoke in the atmosphere | Offices |
Sound | Levels of sound | Security alarm systems |
Tilt | Angle of tilt | Windows in security alarm system |
Touch | Detects if one object bumps into another | Computer controlled robots |
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Sensors