Design On Modular Circuit Of Biomedical Magnetoelastic Detection System

Magnetoelastic sensor is a newly developing kind of wireless sensor based on effect of Magnetostrictive. Using coupling resonance of magnetic field as measurement method, mangetoelastic sensor is able to effectively perform fast and accurate measurement of a verity of physical parameters, such as reacting force, loading mass,and dynamic viscosity.Particularly, magnetoelastic sensor made of Fe-based amorphous alloys turns to be more attractive recently in biomedicine area. This kind of sensor has distinguishing features as known as wireless, passive, cost-effective, highly sensitive, especially suitable for applications like accurately performing harmless measurement in closed space as well asbiological detection in vivo. Therefore, this new kind of sensor can be used in a wide range of potential applications such as physics, biochemistry, and biomedicine.However, the current research of magnetoelastic sensor often focuses on the design of resonant frequency circuit for sole usage, based on impedance or induction from frequency-scanning. In this case, magnetoelastic sensor’s functionalities will not be fully taken advantage of by such single-purpose design.To solve the problem addressed previously, a platform for resonance frequency detection of magnetoelastic sensor based on a combination of several modules is introduced in this article. With studies of impedance and induction from frequency-scanning and analysis of multiple measurement methods, this new platform,as well as its hardware circuit, is designed and built with different functional modules including control module, AC source excitation module, DC offset module, and amplitude and phase measurement module. In addition, detailed specifications for each modules are generated. With flexible combined matches of functional modules for different purposes, this platform provides a general magnetoelastic-sensor-based resonance frequency measurement solution with portability, flexibility and low cost.After unit test of each modules, three typical combinations of modules have been chosen and compared for system test of magnetoelastic measurement platform.Preliminary result has been collected and analyzed. The result has proved each module’s functionality and the system design’s practicality.