Research And Design Of Portable Multifunctional Physical Therapy Devices

With the development of the times and the progress of human civilization,people have continuously enhanced the awareness of health.Numerous physiotherapy products began to enter the ordinary families.These physiotherapy products can play an active role in promoting blood circulation,relieving fatigue,and treating soft tissue pain.However,there are many problems in physiotherapy equipment on the current market,such as single function,expensive price and lack of comfort.The paper designs a portable multi-functional physiotherapy device,which has three functions:electromagnetic physiotherapy,electrical stimulation and ultrasonic physiotherapy.The device can provide family members with different physiotherapy methods.Considering the portability,comfort and reliability of the device,the heating plate is made of flexible graphite sheet and carbon fiber filament,which can enhance the sense of comfort.The needle adopts conductive electrode sheet,which can increase stimulation area and reduce needling sensation compared with the filiform needle.The concave piezoelectric ceramic plate is used in the ultrasonic transducer.Ultrasonic wave generated by the transducer focuses on the internal tissue,which can reduce the loss in the process of transmission.On the design of hardware,STM32F103,a high-speed and high-capacity integrated chip,was selected as the central processing unit in this paper.In the electromagnetic physiotherapy mode,RC circuit is used for measuring the real-time environment temperature of the heating plate,and the heating plate is heated by the load switch.In the electro-acupuncture mode,boost circuit,pulse signal conditioning circuit and over-current protection circuit are designed in this paper,and circuit design and device selection are discussed in depth.In the ultrasonic mode,the driving power is designed to excite the ultrasonic transducer,and the impedance matching circuit between boost circuit and transducer is analyzed in detail.On the design of software,RC temperature measurement algorithm is used to control the temperature of heating plate so that it can be adjusted adaptively,and average method is used to eliminate temperature singularities.Incremental PID algorithm is used to automatically adjust PWM signal to realize automatic control of ultrasonic power.Finally,the paper tests and analyzes the capability and accuracy of the device.The maximum error of hyperthermia temperature is±3 degrees Celsius.The surface temperature unevenness of the heating plate is less than 10%,and the response time does not exceed 15 minutes.In the electro-acupuncture mode,continuous pulse,dense pulse and intermittent pulse can be output stably.The frequency range is within 30~150Hz,the voltage range within 70~85V,the pulse width within 1~10ms,and the upper limit of output current is 40mA.The frequency of the ultrasonic wave is 1 MHz,the maximum error rate is±1%,and the power is 0.1 W/cm~2 and 0.2 W/cm~2,the maximum error rate is±10%.To summarize,the portable multi-functional physiotherapy device designed in this paper meets the design requirements,which has practical application value.