So an object that breaks this field reduces the voltage and triggers a signal to activate. Then the coil uses a ferrite core to create an electromagnetic field. Then the device can translate that into voltage.Īn inductive proximity sensor has an oscillator that creates a fixed wave to drive a coil. So a change in force will change its capacitance. So the device interprets that voltage to figure out velocity and orientation.The second can sense static (like gravity) and dynamic (like human movement) acceleration. The first has teeny crystals that react to acceleration, and this reaction creates a voltage. The two most popular accelerometers are piezoelectric and capacitive. In your car, proximity sensors keep you from hitting the curb or a bystander.And on your phone, these will turn your touchscreen off if you hold it to your ear.Plus, in industry, they can keep separate parts from clashing. And in laptops, they protect hard drives from damage if they fall.Īlso safety and convenience. For example, in cars, accelerometers activate airbags in crashes. And dynamic means movements like tilting or turning your phone.Ī proximity sensor can detect a variety of nearby objects without coming in contact with them. Static usually refers to a force like gravity. An accelerometer measures acceleration, both static and dynamic.