Measuring Gaps Using Planar Inductive Sensors Based on Calculating Mutual Inductance

We present a new method to calculate the gap from measured coil inductance by studying the mutual inductance between the sensing coil and the target plate. From our analysis, we found that with this method only one calibration curve is needed for measuring the gap between the sensing coil and a metallic target plate made of different materials. We demonstrated this method can provide large measurement range (500 µm - 5000 µm) for inductive sensor with decent accuracy. The method can be widely used to 2D planar inductive sensor which is for facilitating measuring gap and detecting metallic objects in machinery and automation equipment made of various materials.

Source: Sensors and Actuators A: Physical - May 22, 2019 Category: Physics Source Type: research