Design And Experimental Study Of Inhibitory System For Parkinson’s Resting Tremor

Parkinson’s resting tremor is a motor disorder neurological disease that often occurs in the elderly.Its main symptom is involuntary rhythmic tremor on one or both sides of the body.Although tremor does not endanger people’s lives,it seriously affects the daily life of patients and causes great pain to patients.At present,the exact mechanism of tremor is not clear.Conventional drug therapy and surgical treatment have the disadvantages of high cost,large side effects,and often accompanied by complications.Therefore,the study of a new method of suppressing tremor has great significance and practical value.Based on the principle of antagonism,this paper uses functional electrical stimulation to achieve the purpose of tremor suppression.The design of the tremor suppression system is studied.It carried out simulated tremor suppression experiments in healthy people and clinical tremor suppression scientific experiments inpatients.Firstly,the generation and characteristics of the surface EMG signal are analyzed.The EMG signal detection system is designed by our research group in the early stage,the system adopts a design scheme of low power consumption,single power supply,small size,high signalto-noise ratio,and removal of functional electrical stimulation artifacts.Since it is a pair of antagonistic muscles that are detected and stimulated,the application of electrical stimulation signals will interfere with the detection of EMG signals.Therefore,it is necessary to remove functional electrical stimulation artifacts to detect EMG signals.The detection module is used to detect the myoelectric signal of voluntary motion,simulates the myoelectric signal of tremor and the electromyographic signals in patients with tremor.At last,the signal characteristics of autonomous motion signals and tremor signals are analyzed.Secondly,the common pattern recognition algorithms of tremor signals are introduced,then based on the simulation data and the tremor data of the patients,the effectiveness of the algorithms are verified.The adaptive pattern recognition algorithm is designed for different individuals.The tremor signal is identified from the detected s EMG signal,and the instantaneous characteristic parameters of the tremor signal are estimated to control the output of the functional electrical stimulation signal.Thirdly,the design of the functional electrical stimulation system is introduced.Based on the previous work of our research group,a single-channel functional electrical stimulator was designed.It consisted of the functional electrical stimulation core circuit,and the complementary current source circuit.The software design of the system is carried out by using the algorithm designed in Chapter 3.The output pulse of the functional electrical stimulation system is charge balance bidirectional asymmetric pulse.The stimulus signal has the characteristics of adjustable amplitude,pulse width and frequency.Finally,a functional verification experiment of the tremor suppression system with functional electrical stimulation was carried out.First,an experimental platform for functional electrical stimulation to suppress tremor was established.Two indicators,namely the rate of tremor suppression and the joint angle signal recorded by the three axis acceleration sensor,were proposed to evaluate the effectiveness of tremor suppression.The simulation of tremor suppression experiments in healthy subjects was carried out,and the relationship between the tremor suppression rate,stimulation frequency and stimulation amplitude was studied.Then,based on the simulated tremor suppression experiment in healthy people,a clinical trial of Parkinson’s resting tremor suppression was carried out.To carry out relevant experimental research on the functional electrical stimulation tremor suppression system based on surface EMG signal control.The ultimate goal is to achieve a single degree of freedom of the wrist for the patients with Parkinson’s resting tremor,under the premise of being safe and reliable and not affecting voluntary movement.