Yoke Topology Optimization of the Bias Magnetic System in a Magnetostrictive Sensor

자기변형 센서 바이어스 자기계의 요크 위상최적설계

  • 김윤영 (서울대학교 기계항공공학부) ;
  • 김우철 (서울대학교 대학원 기계항공공학부)
  • Published : 2004.07.01


A magnetostrictive sensor is a sensor measuring elastic waves. Because of its unique non-contact measurement feature, the sensor receives more attentions in recent years. These sensors have been mainly used to measure longitudinal and torsional waves in ferromagnetic waveguides, but there increases an interest in using the sensor for flexural wave measurement. Since the performance of the sensor is strongly influenced by the applied bias magnetic field distribution, the design of the bias magnetic system providing the desired magnetic field is critical. The motivation of this investigation is to design a bias magnetic system consisting of electromagnets and yokes and the specific objective is to formulate the design problem as a bias yoke topology optimization. For the formulation, we employ linear magnetic behavior and examine the optimized results for electromagnets located at various locations. After completing the design optimization, we fabricate the prototype of the proposed bias magnetic system, and test its performance through flexural wave measurements.


Magnetostrictive Sensor;Bias Magnetic Field;Electromagnet;Yoke;Flexural Wave


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