Global Position Sensor Market Research Report

Position Sensor

Sensors are usually classified on the basis of their applications. For example, sensor used for measurement of pressure is known as pressure sensor and sensor used for measurement of humidity is known as humidity sensor. A type of sensor used for measuring the distance travelled by an object in regard to its reference point is known as position sensor. It is actually a measurement of an object movement or displacement from reference point or the initial position.

The motion of the object can be linear, angular or multi-axis. On the basis of motion, sensors can be classified as linear position sensor or angular position sensor. Sensor used to detect object movement in straight line is termed as linear position sensor and sensor used to detect angular movements are termed as angular position sensor or rotational sensor.

Position sensor can be classified on the basis of their sensing principles in order to measure the displacement of an object such as potentiometric position sensor, capacitive position sensor, linear voltage differential transformer, magnetostrictive linear position sensor, eddy current based position sensor, hall effect based magnetic position sensor, fiber-optic position sensor and optical  position sensor.

Potentiometric Position Sensor

This sensor utilizes resistive effect for sensing. The basic principle is just the resistive or conductive track. For measuring the displacement of an object, a wiper is joined to the object or part of object. This wiper is in contact with the track. Potentiometric position sensor is convenient to use and of low cost and low technology. The main disadvantage is wear as a result of moving parts. Other disadvantages are low accuracy and repeatability, and limited frequency response.

The three main types of potentiometers

a)      Wirewound

b)      Cermet

c)      Plastic film

Linear Variable Differential Transformer

This is a type of position sensor which is free from mechanical wear problems. It comes into the category of inductive type position sensor. It is based on the same principle as AC transformer which is a movement measuring device. This device is very useful to measure linear displacement.

Eddy current sensor

It is not used for the measurement of displacement or angular rotation. This type of sensor is used to detect any object’s presence in front or within close proximity. It is a non contact position sensor based on the use of magnetic field for detection.