A Linear-Encoder-Based Displacement Sensing Approach for Cost-Sensitive Applications

Abstract

A new low-cost displacement sensing approach is put forward. It employs physical multiplication by using multiple linear encoders and differential grating codestrips, and the differential phase configuration is mechanically guaranteed; furthermore, a flash signal processing circuit comprising time sequence generator, counter and D/A with no microprocessors involved is also developed. Theoretical analysis is presented, and a test system using Heds-9730 as the detecting unit is built, and then experiments on an electromagnetic actuator are carried out. The measured results agreed well with the original, and the results prove that the sensing approach can achieve high sampling rate, high resolution and cost saving, thus providing an effective displacement measuring means for cost-sensitive applications.