Research Of Piezomagnetic Signal Detection Based On Cortex Embedded Processor

Lossless stress detection technology based on piezomagnetic theory is widely needed in oil field, railway and other advanced manufacture area. This paper discusses a new way of stress detection according to piezomagnetic sensor's impedance changes. Then combined with embedded technology, designed a impedance detecting device based on STM32 and AD5933. More details about the research include:1. Familiar with necessary magnetic and electronic theory, collected plenty of relative materials. It includes magnetostriction effect and reversible magnetostriction effect, theories in magnetic circuit, transformer theories. This provides reference for following deeper research.2. Collected information of exsiting piezomagneticsensor, basically understood the principle. Discuss a new way of stress detection according to piezomagnetic sensor's impedance changes, based on exsiting piezomagneticsensor using voltage as output signal. Designed a new model of piezomagnetic sensor based on transformer theory, and demonstrated it theoretically.3. Carefully read and translated the reference manual of IDC chip AD5933, understood its internal structures, and the process of its usage. A plenty of testing is accomplished, its precision is verified. In addition, the means of improving AD5933's precision is provided.4. Carefully read and translated the reference manual of embedded MCU STM32 which based on Cortex core, carefully read and rewrited the code of all peripherals, a careful debug is finished. The characterization of STM32 is mastered. Some errors in demo are corrected, such as errors in I2C read and write function.5. Designed a impedance detecting device based on STM32 and AD5933, and applied it in a program. Participated in schematic design and PCB design.6. Elementarily studied Zigbee wireless network technology and programming in embedded system windows CE. Discuss a way of building wireless-sensor network, provided a preliminary blue print.