A Heart Sound Detection And Motion Intensity Evaluation System Based On Android

Sports plays a very important role in the modern daily life, more and more social resources are moving into this filed now. Blossoming of gym, community sports grounds and increasingly popular intelligent bracelets are good examples. With the rapid increasing of fitness, the allocation of resource in sports medicine dose not adapt to the times,especially in the movement of personal health care,there is a great demand of gap. Sudden cardiac death is a big problem to the masses of sports fans, the motion intensity of mountain climbing and distance running for aged people is a problem needed to resolve especially. Therefore, this article puts forward a heart sound detection and motion intensity evaluation system based on Android which can be used as a personal auxiliary testing tool in the field of sports medicine. By the analysis of real-time heart sound, this system can figure out the current motion intensity, give suggestion to prevent cardiovascular disease, and reduce the occurrence of sudden cardiac death events. On the other hand, the system can also be used as a detection method of cardiac rehabilitation, reducing rehabilitation nursing cost effectively.Firstly, this paper discusses the characteristics of different feature parameters. On the base of above result, considering the requirement of hardware resource on mobile phone, this paper choose frequency domain formant as the feature parameters of this system, and introduces the extraction process of the feature parameters. To provide reference for motion intensity, this paper converts frequency domain formant into graphics.Secondly, this paper analyses the relationship between heart sound and motion intensity. Because the heart sound is a kind of external manifestation of cardiac activity, and heart muscle strength, heart rate and heart blood flow are closely related to the intensity of human motion in the cardiac loading, therefore heart sound could be used to detect the motion intensity. Reffering to a lot of research results, this paper proposes a method to evaluate motion intensity based on heart sound. This paper uses heart sound signal to calculate the heart muscle strength, heart rate and heart blood flow before and after exercise, and then concludes the motion intensity effect on cardiac loading by comparison and analysis. Hence, the current motion intensity can be calculated and rationalization exercise suggestion is be given. On the other hand, this paper can reflect the rehabitation if cardiovascular disease, through out long-term preservation of motion intensity data.Finally, the design of a mobile phone application based on Android platform. Limited by the computing power of mobile phone, this paper optimizes the method of denoising, framing, envelope extraction of heart sound signal, programs it on Android platform at last. In the process of research and development, voice recognition/control, database technology were added into this system to simplify the operation.After the test, this system operates stably on Android mobile phone. What is more, it can do extraction, identification and analysis of feature parameters in the heart sound signal, and then, make accurate assessment to the current motion intensity. This system has reached the design requirements, also has a very high value of market popularization.