On The Frozen Gait Monitoring System Based On Multi-Sensor

Gait freeze(FOG)is a common symptom of Parkinson’s disease(PD).It is mainly manifested as:the patient cannot complete the lifting of the foot smoothly when walking or turning,and the body is prone to fall forward due to inertia,resulting in the injury of the patient Gait freezing is an important basis for the severity of Parkinson’s disease,so monitoring it is of great significance for the clinical treatment of Parkinson’s disease and the daily monitoring of Parkinson’s disease patients.In this thesis,a multi-sensor-based frozen gait monitoring system is designed.It’s main contents and innovations are as follows:(1)The foot pressure sensor in gait monitoring system is designed.The insole for pressure measurement is made by using the thin film pressure sensor array,and the software and hardware of the plantar pressure signal acquisition and transmission system with bluetooth wireless transmission function are designed.(2)The joint flexible Angle sensor in gait monitoring system is designed.The flexible sensor based on silver electrode Ionic polymer was prepared by chemical deposition method,and the surface electrode deposition effect and electrode structure were optimized by controlling the reaction speed and temperature.The flexible sensor was fabricated by using the principle of silver mirror reaction,and the sensor was modeled.(3)A novel method of frozen gait determination is presented.The change in the severity of frozen gait can be reflected by the freezing index,which is defined as the ratio of energy in the frozen frequency band to energy in the moving frequency band.In this design,the numerical range of freezing index can be obtained through the freeze gait monitoring system based on multiple sensors,and then the appropriate threshold can be selected.(4)The experiment of frozen gait monitoring system was carried out.The "frozen gait" was simulated by the laboratory members,and then the vertical linear acceleration and freezing index of the lower leg were obtained through calculation.Then the waveform of acceleration and freezing index was compared with that of normal people walking.Finally,appropriate threshold was selected to determine the occurrence of frozen gait.