Design And Implementation Of Portable Digital Stethoscope System

In order to ensure the safety of life and property of the crew of the world,the international organization issued the STCW convention.The Convention puts forward rules and requirements for seafarers' duty,which is of positive significance to maritime safety.The real-time monitoring of the crew's health has long-term significance for improving the health and safety of the crew.In this paper,a portable digital stethoscope system based on Bluetooth Low Energy is developed.It can collect crew's heart sound,lung sound and intestinal sound signals in real time,and then deal with the sound signal of the collected auscultation,and allow the doctor to make auscultation through the Bluetooth Low Energy transmission.The system is mainly composed of two parts:hardware and software.The structure and characteristics of the system are as follows:(1)The design of the hardware circuit of the system: The sensor realizes Crew's auscultation signal.After the signal processing of the preamplifier circuit,filter circuit of a series of circuit design,the digital stethoscope achieves a low-noise amplification of auscultation sound.After the filter circuit,the sound signal of auscultation is divided into two channels.On the one hand,it is send to the power amplifier circuit,the function of playing the Crew's auscultation sound completed,and on the other hand,it is send to the STM32F103C8T6 to make AD conversion.It outputs a digital signal with a strong anti-interference sound,and sends it to the Bluetooth module DA14580 through the USART interface.Through the Bluetooth Low energy technology,the auscultation result is uploaded to the mobile APP client.(2)The design of the system software part: main controller software and Bluetooth chip software two most of the design work.It mainly includes ADC program,USART communication program,Bluetooth wireless transmission communication program and completed the main basic software design of the whole digital stethoscope system.(3)System Testing: This article tested the hardware and software components.After testing,on the one hand,On the one hand,the auscultation sound collection circuit performance,Bluetooth wireless transmission distance and stability experiment were completed.on the other hand,the auscultation results are uploaded to the mobile phone APP client via wireless transmission,and the function of the digital stethoscope is verified.