尺蠖型超磁致伸缩旋转驱动器驱动信号设计与试验

为了解决传统的“信号发生器+功率放大器”产生的信号无法满足尺蠖型旋转驱动器多路、正方波波形需求的问题,设计了一种通过Cmos控制脉冲模块“通-断”时机的信号控制器,从而得到特定时序的3路正方波信号。通过这种方案得到的3路驱动信号为正方波电流信号,从而避免了超磁致伸缩材料的“倍频”现象的发生。通过设置信号周期、占空比和延迟等参数,能够输出设定时序的三路正方波驱动信号。根据电压定律,将正方波简化成阶跃波形,建立了驱动信号的电流模型,并进行了参数辨识。在工作频率范围内,电流解析式能准确地表示电流信号。搭建试验平台进行了试验测试,试验结果表明,在工作频率范围内,信号控制器输出的正方波波形优于“信号发生器+功率放大器”产生的方波信号,设定的3路信号能够驱动尺蠖型旋转驱动器产生步进旋转运动。通过优化驱动信号时序,将旋转驱动器最大工作频率由160Hz提至210Hz。

Driving Signal Design and Experiment of Inchworm Giant Magnetostrictive Rotary Actuator

In order to solve the problem that the signal generated by traditional “signal generator+power amplifier” cannot meet the demand of multi channel and square wave waveform of inchworm rotary driver, a signal controller was designed to generate multiple square waveforms by on-off of a Cmos control pulse module. The three driving signals obtained through this scheme were square wave current signals, which can avoid the occurrence of “frequency doubling” phenomenon in giant magnetostrictive materials. By setting the parameters such as the period, duty cycle and delay of the signal, the three-channel square wave driving signal with set timing can be output. According to the voltage law, the square wave was simplified to step wave. The current model of driving signal was established, and the parameters were identified. The current analytical formula can accurately represent the current signal within the operating frequency range. The experimental platform was built and tested, the experimental results showed that the square wave output by the signal controller was better than that by the traditional scheme in the working frequency range, and the set three-way signal can drive the inchworm rotary driver to generate step-by-step rotation motion. The angular displacement response of the rotating actuator was analyzed. By optimizing the timing of the driving signal, the maximum operating frequency of the rotary driver was increased from 160Hz to 210Hz.