Millisecond model updating for structures experiencing unmodeled high-rate dynamic events
Millisecond model updating for structures experiencing unmodeled high-rate dynamic events
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DOI：
10.1016/j.ymssp.2019.106551
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发表时间：
2020-04-01
影响因子：
8.4
通讯作者：
Scheppegrell, James
中科院分区：
文献类型：
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作者：
Downey, Austin;Hong, Jonathan;Scheppegrell, James
实时控制的下一代主动结构，经验未建模的高速率的动态事件需要一个最新的数值模型的结构系统。经历未建模的高速率动态事件的主动结构的例子包括高超音速飞行器、主动爆炸减缓和弹道包。由于这些结构在其中操作的动态环境，因此在小于10 ms的时间尺度上更新系统的数值模型。此外，对未建模的高速率动态事件的监测的要求意味着所提出的模型更新技术不能依赖于预先计算的数据集或离线训练，因此，实时结构更新技术必须能够动态地学习结构的状态。这项工作提出并验证了毫秒误差最小化模型更新技术的算法框架，该技术通过最小化结构的测量状态和一系列并行化模型之间的误差来更新结构系统的有限元分析模型，所述并行化模型在结构移动通过高速率动态事件时与结构实时计算。所提出的算法进行了数值和实验验证，使用实验测试台设计，以模拟动态事件的弹丸在弹道环境中，包括一个悬臂梁和一个可移动的辊支持，引入一个不断变化的边界条件，以模拟结构系统的变化（即损坏）。实验结果表明，可以准确地跟踪和更新每4.04 ms的测试台上的辊的位置与2.9%的准确度（10.05毫米超过350毫米的梁）的标准测试配置文件，该算法可以跟踪辊的运动，通过冲击载荷。此外，该算法表明，它能够跟踪随机辊运动的准确率为3.73%。估计辊的位置所需的时间来收集足够数量的振动数据，需要不断激励的结构，所提出的算法的鲁棒性所造成的延迟进行了讨论。(C)2019爱思唯尔有限公司版权所有。
Real-time control of next-generation active structures that experience unmodeled high-rate dynamic events require an up-to-date numerical model of the structural system. Examples of active structures that experience unmodeled high-rate dynamic events include hypersonic vehicles, active blast mitigation, and ballistic packages. Due to the dynamic environments that these structures operate in it follows that a numerical model of the system be updated on the timescale of less than 10 ms. Furthermore, the requirement for the monitoring of unmodeled high-rate dynamic events means that the proposed model updating technique cannot rely on precalculated data sets or offline training, therefore, the real-time structural updating technique must be capable of learning the state of the structure on-the-fly. This work proposes and validates an algorithmic framework for a millisecond error minimization model updating technique that updates a finite element analysis model of the structural system by minimizing the error between the structure's measured state and a series of parallelized models that are calculated in real-time with the structure as it moves through the high-rate dynamic event. The proposed algorithm is numerically and experimentally validated using an experimental testbed designed to simulate the dynamic events of projectiles in ballistic environments that consists of a cantilever beam and a movable roller support that introduces a continuously changing boundary condition to simulate a change in the structural system (i.e. damage). Experimental results demonstrate that the location of the roller on the testbed could be accurately tracked and updated every 4.04 ms with an accuracy of 2.9% (10.05 mm over a beam of 350 mm) for a standard test profile and that the algorithm could track roller movement through an impact loading. Furthermore, the proposed algorithm demonstrated it was capable of tracking stochastic roller movement with an accuracy of 3.73%. The delay in the estimated roller position caused by the time required to collect a sufficient quantity of vibration data, the need for constant excitation of the structure, and the robustness of the proposed algorithm are discussed. (C) 2019 Elsevier Ltd. All rights reserved.