Large Measurement Range Displacement Sensor Based on Hall Elements

This paper presents a new method in high speed displacement measurement which is widely needed in projects such as reservoir dam, bridge state, tunnel security monitoring as well as in mechanic manufacture industries. The proposed method uses Hall elements as nerve cells logically organized by Complex Programmable Logic (CPLD) IC for each sensor exciting, signal conditioning and processing. This new kind of displacement measuring transducer achieves not only in rapid displacement moving responding, but also in multi interface connection to a length which meets the requirement. Since the principle is based on series regulated nerve cells (Hall element) distribution, the measurement error is limited to an absolute distance between two Hall elements. The simulation and experiments are provided to prove credibility and feasibility in real time. Moreover, mechanical structure of motor rotation tests and verifies the accuracy.