Design Of The Medical Control Blanket Control System Based On STM32

As a medical device, medical control blanket has been widely used in clinical departments for controlling patient temperature physically. Most of the domestic medical control blankets have poor security and reliability, low temperature accuracy, unfriendly interface and other shortcomings. To compensate for these shortcomings, this paper proposes a design of the medical control blanket control system on the basis of embedded technology, digital sensor technology, touch screen technology and intelligent control algorithm.This control system uses ST company’s STM32F103VET6 as the core processor, with 7 inch touch screen as the human-computer interface to get the target temperature value set by the user. Meanwhile, the control system uses sensors to collect multichannel signals such as circulating liquid’s temperature, patient’s body temperature and so on. Finally the PWM pulse is output with different duty cycle. Through the control-output circuit, the PWM pulse can control the semiconductor refrigeration module cooling or heating the circulating liquid, making the circulating liquid’s temperature reache the set value. The input section, control section, and output section are isolated from each other by ADuM chips, which make the control system safer and more reliable. There are some spare interfaces on the control system, which are prepared for the necessary development or promotion. The control system software development is based on the embedded real-time operating system uC/OS-Ⅱ which can improve the real-time performance and stability of the software. The control system uses the digital increment PID algorithm which also has integral separation function, and the PID parameters are confirmed by relay feedback self-tuning algorithm. These algorithms can guarantee the control system has a better control precision. The operation interface is developed on VisualTFT, which can provide users with a friendly, simple and elegant interface, moreover, it can enhance the competitiveness of products.The hardware and software of the control system are debugged entirely with good effects. The control system has the advantages of complete functions, high temperature accuracy, high security, reliability and stability, strong anti-interference capacity, nice expansibility and friendly interface. The control system has great practical value and broad market prospect.