Lightweight active and passive energy dissipation devices for enhanced and adaptable crashworthiness performance

拟议的研究计划将侧重于培养高素质的人才，进行独特的实验，数值和理论研究，以开发新型和高性能的自适应结构能量吸收装置，其中力/位移响应根据设计或需要进行调整。被动和主动自适应消能结构将被设计、制造和评估，以便为许多相关领域的应用提供适当的性能数据，包括但不限于军事、航空航天、船舶、汽车和个人安全设备行业。该研究团队将集中精力开发自适应能量耗散装置，利用切割变形模式，在低速率和高速率压缩和拉伸载荷条件下最大限度地提高系统性能。该研究项目的长期目标是开发高性能、新颖、坚固和有效的能量吸收装置，以减轻在广泛的安全应用中由于福尔斯坠落、汽车碰撞、行人碰撞、爆炸或炸弹爆炸造成的严重伤害或死亡。实验研究将在准静态、动态和弹道载荷条件下进行，学生将使用最先进的设备，包括但不限于：（1）独特的长冲程和传统的（通用）准静态拉伸/压缩试验机，（2）落塔冲击试验机，（3）定制的气动炮和屏障以及（4）分离式霍普金森压杆（SHPB）装置。与开普敦大学（南非）研究人员的合作努力将提供机会，利用弹道摆测试主动和被动能量耗散系统。通过使用传感器、高速摄影和数字图像分析软件以及光学应变测量系统（使用低速和高速摄像机），将对能量吸收器的变形特性和性能进行量化。培养学生开发高质量，经过验证和验证的数值模型也将是拟议研究的重点。采用传统拉格朗日单元公式和非传统欧拉、光滑粒子流体动力学（SPH）、无单元伽辽金（EFG）和光滑粒子伽辽金（SPG）公式的大变形、高应变率有限元模型将用于申请人先前开发的工程模型的改进，用于所提出的结构能量耗散装置的变形模拟。分析模型也将得到改进和扩展，用于预测器件性能和增强。建议的研究补助金将提供援助，以培训高素质的人才，并在开发这些上级消能装置方面进行研究。

The proposed research program will focus on the training of highly qualified personnel to undertake unique experimental, numerical, and theoretical studies towards the development of novel and high performing adaptive structural energy absorbing devices, where the force/displacement response adjusts based upon design or as needed. Both passive and active adaptive energy dissipation structures will be engineered, fabricated, and assessed in order to provide appropriate performance data for application to many relevant fields, including but not limited to, military, aerospace, marine, automotive and personal safety equipment industries. The research team will concentrate efforts on the development of adaptive energy dissipation devices exploiting a cutting mode of deformation to maximize system performance under low and high rate compressive and tensile loading conditions. The long term objectives of this research project are to develop high performance, novel, robust, and effective energy absorbing devices so as to mitigate serious injuries or death as a result of falls, automotive crashes, pedestrian impacts, blasts, or bomb explosions in a broad range of safety applications. Experimental studies will be conducted under quasi-static, dynamic, and ballistic loading conditions and students will be utilizing state of the art equipment, including but not limited to, (1) a unique long stroke and traditional (universal) quasi-static tension/compression testing machines, (2) a droptower impact testing machine, (3) a custom built pneumatic cannon and barrier and (4) a Split Hopkinson Pressure Bar (SHPB) apparatus. Collaborative efforts with researchers at the University of Cape Town (South Africa), will provide the opportunity to test both active and passive energy dissipation systems using a ballistic pendulum. Quantification of the deformation characteristics and performance of the energy absorbers will occur through the use of transducers, high speed photography and digital image analysis software, as well as optical strain measurement systems (using both low and high speed cameras). Training of students in the development of high-quality, verified and validated numerical models will also be a focus of the proposed research. Large deformation, high strain rate finite element models employing both traditional Lagrangian element formulations and non-traditional Eulerian, smooth particle hydrodynamic (SPH), element free Galerkin (EFG) and smoothed particle Galerkin (SPG) formulations will be utilized in the advancement of the applicant's previously developed engineering models for deformation simulation of the proposed structural energy dissipation devices. Analytical models will also be advanced and extended for prediction of device performance and enhancement. Support from the proposed research grant will provide assistance to train highly qualified personnel and conduct research in the development of these superior energy dissipation devices.