1. Medical College , Zhejiang University, Hangzhou, Zhejiang 310027, China
2. College of BME & IS, Zhejiang University, Hangzhou, Zhejiang 310027, China
Abstract：The low cost and contactless displacement detection with long dynamic range is becoming an objective requirement . After the detailed analysis on the negative factors for achieving high resolution performance in the Giant Magneto Resistive (GMR) based displacement detection systems, a customizable high-frequency magnetic field source with proportional gradient intensity was built to meet the requirement of long dynamic range detection, meanwhile, the lock-in amplification was associated with data-infusion to accomplish the detection of high resolution for displacement in magneto field. From these results of testing, it was found that the detection system can reach to high sensitivity of 0.1 micro-meters in the dynamic range of 0~100mm at least, therefore, the rationality of the design objective seem to be proved. These results will provide an available prototype for the design of MEMS in an amount of applications of high-precision contactless displacement detection, which include the research of bone strength in vivo.
［1］关信安, 等. 双频激光干涉仪［M］. 北京:中国计量出版社, 1987, 1-5.
［2］Ford R M, Weissbach R S, Loker D R. A Novel DSP-based LVDT Signal Conditioner［J］. Instrumentation and Measurement, 2001, 50(3):768-773.
［3］Datasheet of the magnetic sensor AB001-02 from NVE Corporation［EB］, http://www.nve.com/Downloads/analog catalog.pdf.
［4］van de Veerdonk R , Belin P, Schep K, et al. 1/f noise in anisotropic and giant magnetoresistive elements［J］. Appl Phys, 1997, 82 (12):6152-6164.
［5］高晋占. 微弱信号检测［M］. 北京:清华大学出版社, 2004, 154-196.
［6］黄延军, 沈跃, 魏淑贤. 大位移测量中均匀梯度磁场的构建［J］. 传感器技术, 2005, 24(2):55-59.
2010, Vol. 31 
