Ultrasonic Testing System Of Skeletal Muscle Fatigue Based On Virtual Instrument

Muscle fatigue is a common phenomenon in daily life. Especially when people do physical labor and sports, overtime and vigorous sports will lead to the decrease of the muscle activity efficiency, which is called exercise induced fatigue. The frequency overload movements may lead to muscle injury, disease or even death. The accurate evaluation of muscle fatigue can reduce or avoid injury which is caused by muscle fatigue, and monitor the muscle lesions to provide the reference of the diagnosis of disease at the early stage.During the stage of muscle fatigue, the ultrasonic transmission characteristics especially the attenuation characteristic of muscle will change observably. This paper design a detecting system to evaluate the degree of skeletal muscle fatigue based on the method of virtual instrument design. The details are as follows:(1)The research of the transmission attenuation of ultrasound in muscle. Research the ultrasound attenuation law of muscular tissue during movement process. Based on the transmission characteristic muscular tissue of ultrasound, research the theory of ultrasound can evaluate the degree of muscle fatigue.(2)Design the detecting system to discover the ultrasonic transmission characteristics in muscle tissue. The external clock is employed as the synchronizing signal. The synchronizing signal trigger the computer to make the signal generator to generate ultrasonic excitation signal. Then the sound signal which transmits in muscle will be received with the data acquisition card. And the collected data will be transmitted from the board card buffer to the computer in the DMA transmission mode and saved.(3)Research the evaluation of the degree of muscle fatigue based on the ultrasonic attenuation characteristics. The Lab VIEW is employed to write programs to analyze the ultrasonic signals. The algorithm of fatigue evaluation is implemented according to the muscle tissue sound transmission characteristics of the theory.Experimental results show that the designed system can analyze the ultrasonic signal transformed before/after muscle tissue, recognize the magnitude feature of the muscular tissue in different working condition and tell the difference of the magnitude feature of different muscular tissue and the judge whether the muscular tissue reaches the state of fatigue.