Sensors

Sensors are devices converting any kind of physical attributes (temperature, luminance, force, acceleration etc.) to a understandable form for humans or machines. With the help from sensors the microcontroller receives information from the surrounding environment and makes decisions based on it. There are many types of sensors, approximately 195 different types are listed in Wikipedia. Only sensors with electrical output signal can be connected to microcontrollers. Based on electrical output signal, is possible to segment sensors as digital and analogue sensors.

In analogue sensor any change in physical attributes changes one of its electrical values, usually voltage, current or resistance. Since microcontrollers are digital devices, the signal have to be converted from analogue to digital before delivering it to controller. For this purpose analogue-digital converters are used which usually are built-in to the microcontroller.

Analogue sensor which already includes digitizer of information, it is called digital sensor. Digital sensors can also standardize information, calibrate sensors and perform a great deal of other functions. There are many ways for transmitting info from digital sensor to microcontroller: the easiest is with logical signals, more complex way – through some data link interface. The following exercises though, are introducing simpler sensors and sensors known in robotics.