Concepts for the design of smart sensors and smart signal processors and their application to PSD displacement transducers

Abstract

General ideas for a systematic design of smart sensors and processors are presented. Although the ideas are based on classical theory, their consequent and systematic application has been shown to result in novel, simple, and accurate processors. The concept is demonstrated by a novel design for a PSD (position-sensitive device) displacement transducer. With a simple, low-cost circuit, the processor inaccuracy is less than 10/sup -4/ for the displacement range of 3 mm, which is ten times better than that of the PSD itself. The PSD nonidealities form the main cause of the limited accuracy. The output signal is especially suited for processing with microcontrollers. The measurement time is about 100 ms.<>