High-reliability incremental-type position transducer with autocalibration capability

This paper gives a review of digital position transducers with special retrospect on problems regarding large-scale position measurement. Incremental encoders are simpler, cheaper and they can provide high measurement resolution. However, they have well-known drawbacks of accumulating reading errors and loss of position because of power interruption. This paper proposes the solution that provides frequent autocalibration of the measuring system in a simple manner, using pseudorandom encoding. The applied method provides reliable detection of errors and makes the system resistant to oscillations along the movement course. A transducer with 12-bit output resolution is realized, and its most important characteristics are presented in the paper.