基于直接数字合成的便携式超声波治疗仪研制

Development of Portable Ultrasonic Therapeutic Apparatus Based on Direct Digital Synthesis

针对家用超声波治疗仪出现的电-声转化效率低,输出强度单一,精度低,体积大等问题,提出一种基于直接数字合成的便携式超声波治疗仪。治疗仪采用低功耗STM32L151控制直接数字合成器产生超声驱动信号,经过驱动电路和滤波电路调节后,利用功率放大模块驱动压电陶瓷片产生频率为1 MHz,强度为300mW/cm2、500mW/cm2、1000mW/cm2、1300mW/cm2四个档位的超声波。反馈调节系统采用Fuzzy神经网络和锁相环结合的频率自动跟踪方法,软件部分采用BP(Back Propagation)神经网络控制器输出动态匹配电感实现动态匹配。实验测试证明,该超声波治疗仪方便携带,具有电-声转化效率高,输出功率稳定,输出声强动态可调,成本低等特点。

Aiming at the problems of low electric-acoustic conversion efficiency,single output intensity,low precision and large volume in household ultrasonic therapeutic apparatus,a portable ultrasonic therapeutic apparatus based on direct digital synthesis is proposed.The treatment instrument USES the low-power STM32L151 controlled direct digital synthesizer to generate ultrasonic drive signal.After the adjustment of the drive circuit and filter circuit,the power amplifier module is used to drive the piezoelectric ceramic chip to generate ultrasonic waves with frequency of 1mhz and intensity of 300mW/cm2,500mW/cm2,1000mW/cm2 and 1300mW/cm2.The feedback regulation system adopts Fuzzy neural network and PLL combined frequency automatic tracking method,and the software part USES BP (Back Propagation)neural network controller output dynamic matching inductance to realize dynamic matching.Experimental tests show that the ultrasonic therapeutic apparatus is convenient to carry,with high electric-sound conversion efficiency,stable output power,dynamically adjustable output sound intensity and low cost.