Automatic Injection System Of Cardiovascular Contrast Media Based On STM32

With the development of semiconductor technology and people’s increasing attention to health,medical equipment has been developed rapidly in recent years,cardiovascular contrast injection in hospitals is widely used,in order to improve the intelligence of contrast injection,this thesis mainly designs an automatic cardiovascular contrast injection system based on STM32H743VIT6.The system mainly consists of a master control module,ECG signal acquisition module,stepper motor control module,heart pressure acquisition module and a host computer.This thesis mainly elaborates the design of the main control module and ECG signal acquisition module,and briefly describes the rest of the hardware design part and software design part.Electrocardiogram(ECG)signal,as a common physiological electrical signal,is of great importance for the prevention and diagnosis of cardiovascular diseases.In this thesis,a low-power,low-noise,gain-adjustable ECG signal acquisition circuit system is designed.This design uses a modular design to optimize the high-precision components in the analog front-end,post-gain filter,input driver,reference,and analog-to-digital conversion regulation circuits required for ECG.The ECG signal acquisition faces two main problems.First,the ECG signal itself has low frequency and low amplitude,which makes it very sensitive to noise,especially low frequency noise.The second is the acquisition process to face problems such as baseline drift,industrial frequency interference,electromyographic interference,motion artifacts and so on.These problems cause a lot of difficulties for the acquisition of ECG signals and need to be solved one by one in the design process.The main control module uses STM32H743VIT6 as the main controller chip of the system.Under the compiled Keil μVision5 environment,the C language is written for each control chip according to the timing requirements of each chip to realize the communication control from the main control chip to each chip,and the input signal is processed and uploaded to the upper computer at the PC side according to the Modbus protocol through the serial port.According to the design and control requirements of the system hardware,the microcontroller control program is written to determine the systolic and diastolic phases of the heart by detecting the R-wave of the ECG signal and triggering the stepper motor to drive the mechanical device to drive the syringe to work and realize the automatic variable flow rate push injection for different cardiac cycles.Automatic variable flow rate pushing of contrast agent by simulating the experiment of cardiac pressure injection.It is an improvement of the existing uniform velocity push injection system to make the push injection process more intelligent.By adding the necessary anti-interference measures to the hardware and software,the whole system has superior performance,stable and reliable operation,and has popularization value.