ABSTRACT

Servo-hydraulic actuators are often used in real-time hybrid simulation to impose desired displacements to specimens and to maintain the boundary compatibility between substructures. Previous studies often consider the servo-hydraulic system as deterministic while experimental results indicate otherwise due to different sources of uncertainties. This study utilizes the generalized likelihood uncertainty estimation method to explore the uncertainties in servo-hydraulic dynamics. Probabilistic distribution and statistical moments are derived for parameters of a linearized servo-hydraulic model based on experimental results. The analysis results are further applied to demonstrate the effects of servo-hydraulic uncertainties on actuator tracking and compared with the corresponding deterministic model.

摘要

伺服液压执行器通常用于实时混合模拟，以对试样施加所需的位移并保持子结构之间的边界兼容性。以前的研究通常认为伺服液压系统是确定性的，而实验结果表明，由于不同的不确定性来源。本研究利用广义似然不确定性估计方法来探索伺服液压动力学中的不确定性。基于实验结果，推导了线性伺服液压模型参数的概率分布和统计矩。分析结果进一步应用于证明伺服液压不确定性对执行器跟踪的影响，并与相应的确定性模型进行比较。