磁流变减振器的可控特性标定方法研究

Controllability calibration of magnetorheological shock absorbers

磁流变执行器应用于振动与冲击控制系统的前提是具有满足控制需求的可控特性,包括力学响应特性和时间响应特性,磁流变执行器的可控特性标定方法建立在由评价力学响应特性的可控阻尼力范围、动态范围和可控运行速度范围以及评价时间响应特性的响应时间的基础上。为了便于磁流变减振器的可控特性研究,文章提出了一种磁流变减振器可控特性的标定方法,并搭建了用于标定磁流变减振器可控特性的实验测试系统。首先,对标定方法中所涉及的磁流变减振器可控力学特性的评价指标进行了概括和阐述;然后,对标定方法中所涉及的磁流变减振器控制执行系统的响应时间进行了重新定义,实现了在对磁流变减振器的响应时间进行标定分析的同时,也可以准确获取其他子单元的响应时间,进而获得整个控制执行系统的响应时间;最后,分别搭建了基于鹭宫伺服液压激振系统和落锤冲击测试系统的实验测试与分析平台,实验测试并标定了磁流变减振器的力学响应特性,并基于鹭宫伺服液压激振系统进行了三角波位移激励条件下磁流变减振器与控制系统的时间响应特性的测试与分析,根据测试与分析结果标定输出磁流变减振器的响应时间。

The premise that magnetorheological actuators can be applied in vibration and impact mitigation systems is the controllability,including the mechanical response characteristics and time response characteristics.The calibration method of controllability of magnetorheological actuators is based on the mechanical response characteristics which include controllable damping force range,the dynamic range and the constant stroking load velocity range,and response time used to evaluate the time response characteristics.In this paper,a calibration method of controllability of magnetorheological shock absorbers is presented,and the corresponding experimental setups are established for the calibration.Firstly,the evaluation indexes of the controllable mechanical characteristics of magnetorheological shock absorber are summarized and explained.The response time of control-actuation system of the magnetorheological shock absorber is redefined,which allows that the response time of all the other subunits can be accurately obtained when the response time calibration process of magnetorheological shock absorber is conducted,thus the response time of the entire control-actuation system can be obtained further.Finally,the experimental test and analysis platforms based on servo-hydraulic testing machine and drop-induced shock setup are established respectively,and the mechanical response characteristics of magnetorheological shock absorber are tested and calibrated.Based on the servo-hydraulic testing machine,the time response characteristics of magnetorheological shock absorber and control system under triangular displacement excitation are tested and analyzed,and the response time of magnetorheological shock absorber could be calibrated accordingly.