Research On Spine Shape Measuring System Based On MEMs Sensor

With the development of society,the study and work pressure are increasing,the incidence of spine malformation is also increasing.Spine malformation will cause serious harm to human physiology and psychology,especially to young people in the period of physical and mental development.Therefore,the promotion of spinal malformation detection and screening has great social value.Currently,there are two kinds of detection methods: radioactive and non-radioactive spinal malformation detection.Radioactive spine malformation detection is a commonly used medical detection method with high accuracy,but it may cause excessive radiation to patients and increase the probability of patients suffering from cancer and other related diseases.In view of the trend of multiple spinal malformation and the urgent need for new spinal morphological detection methods,a new non-radioactive spinal morphological detection system based on MEMS sensor was proposed in this paper.The system has the advantages of no radioactivity detection,high degree of automation,no need for specialized operators,fast detection speed and low cost.The main work of this paper is as follows:(1)A spine shape measure system based on MEMS sensor was proposed.According to the medical criteria for spinal malformation-Cobb angle of scoliosis,Cobb angle of kyphokyosis and angle of axial trunk rotation,the system is designed.Sensor sampling point distribution and sensor selection were determined.A number of MEMS sensor substrates and membrane pressure sensors were installed on the sponge base platform to detect the sampling points of the subject’s back and collect angular velocity,acceleration and pressure data.(2)Software and hardware design.Based on microprocessor STM32F407ZGT6,the core board is divided into micro-processing minimum system,power module,online debugging module,interaction module,storage module,communication module and analog volume signal conditioning module,and the schematic diagram and PCB design of the core board are completed.The MEMS sensor substrate is designed and the communication function of ⅡC bus is programmed.The configuration and data reading of MEMS sensor are realized by ⅡC bus.The signal conditioning circuit of the thin film pressure sensor was designed,and the pressure signal was sampled by the integrated ADC in the microprocessor.(3)MEMS sensor accelerometer sample value abnormal data elimination and error correction.The distribution law of the sampled values of MEMS sensor acceleration was studied,and the abnormal data in the sampled values were eliminated by mathematical statistics.BP neural network was established and trained to correct the error of accelerometer sampling value.The angle of kyphosis and the angle of axial trunk rotation were obtained by calculating the accelerometer sampling value after error correction.(4)Test of the measuring system.The model and the volunteers were tested by the measuring system,and an electronic inclinometer was used to compare the measurement and analyze the accuracy,speed and reliability.The experimental results show that the system can realize the predetermined spinal shape measuring.