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Hardware and Software / Sensors
Sensors
Sensors are input devices that record data about the physical environment around it.
Sensors send data to a microprocessor (computer). They do not make judgements, decisions or control any output devices.
There are many types of sensors used in a variety of household, commercial and industrial applications.
Sensors are reliable, accurate, and don’t get tired; working well in places where humans would rather not be.
Common sensors and their applications
Sensor | Description | Application |
---|---|---|
Magnetic Field | Detect changes in magnetic fields. Can measure the strength and direction of a magnetic field. |
Mobile phones Anti-lock braking Detection of cars at traffic lights Reading magnetic ink characters on cheques |
Motion (infra-red) | Detects movement / heat from objects. | Automatic doors Burglar alarm systems Gaming systems, inc accelerometer Counting, e.g. people or cars |
Temperature | Measures heat generated by an object or system. By measuring the change in heat, the sensor can detect changes in temperature. | Chemical process or reaction Central heating (thermostat) / air-con Greenhouses Ovens, refrigerators and freezers |
Sound | Measures the presence of sound. | Burglar alarm systems Leak detection system |
Moisture / Humidity | Moisture sensors measures the amount of moisture in a certain material whilst humidity sensors measure the amount of moisture in the air, along with its temperature. | Clothes dryer Environmental control / greenhouse, air-con |
Pressure | Measures pressure. | Burglar alarm systems Traffic light controls Chemical processes Liquid through pipes |
Gas | Detects the presence of gas in a certain area. | Pollution monitoring (river) Greenhouse environments Confined areas (space craft, aircraft) Fish tanks / aquariums Carbon monoxide alarms |
Light | Can detect the ambient light level, meaning how bright or dark it is. | Controlling street lighting Burglar alarms (beams of light) Automatic doors Greenhouse |
pH | Measures how acidic or alkaline a material is. | Water treatment plants Pollution monitoring (river) Aquariums Greenhouse |