Aerospace Science and Technology最新文献_第10页

Multipolar expansion for aircraft noise equivalent sources 飞机噪声等效源的多极扩展

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-30 DOI: 10.1016/j.ast.2024.109629

Giorgio Palma , Lorenzo Burghignoli , Caterina Poggi , Jacopo Serafini

Noise generated by aviation poses serious threats to its future development. Noise abatement is pursued by reducing noise at the source and using correct operation practices and farsighted land planning. Since noise evaluation is a computationally demanding process, developing fast techniques is crucial for that noise abatement effort. Widely used approaches separate near-field noise from far-field noise, using the optical analogy or other simplified techniques to radiate to the ground the noise evaluated in the near-field by high-fidelity models, including atmospheric and geographic effects. Here, we propose a multipolar expansion to define equivalent noise sources that can be quickly evaluated to simulate the perceived noise also in proximity of the source. This gives many advantages, such as introducing atmospheric effects closer to the source and using equivalent engine sources in fuselage scattering problems. The expansion is tested against numerical and experimental test cases of aeronautical interest. The results show that the expansion effectively reproduces noise at different distances than that used to train the equivalent source. When the emitted noise is dominated by rotary sources, the method correctly reproduces the amplitude but not the phase of the signals.

航空产生的噪音对其未来发展构成严重威胁。降噪的方法是从源头上减少噪音，并采用正确的操作方法和有远见的土地规划。由于噪声评估是一个计算要求很高的过程，因此开发快速技术对噪声控制工作至关重要。广泛使用的方法是将近场噪声与远场噪声分开，使用光学类比或其他简化技术，将通过高保真模型（包括大气和地理效应）评估的近场噪声辐射到地面。在这里，我们提出了一种多极扩展方法来定义等效噪声源，可以快速评估模拟噪声源附近的感知噪声。这样做有很多好处，例如可以在更靠近声源的地方引入大气效应，在机身散射问题中使用等效发动机声源。针对航空领域的数值和实验测试案例对扩展进行了测试。结果表明，与用于训练等效源的距离相比，扩展有效地再现了不同距离上的噪声。当发射噪声以旋转源为主时，该方法能正确再现信号的振幅，但不能再现信号的相位。

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引用次数: 0

A comprehensive study of a new cylindrical flexible Miura-Ori origami: Kinematics, FEA, and fatigue assessments 新型圆柱形柔性三浦奥里折纸的综合研究：运动学、有限元分析和疲劳评估

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-30 DOI: 10.1016/j.ast.2024.109620

Hadi Ebrahimi Fakhari , Habib Eslami , Mojtaba Moshtaghzadeh , Pezhman Mardanpour

In this paper, we introduced a new cylindrical flexible structure incorporating a multi-story origami based on the Miura-Ori pattern and mathematized kinematics. Our experiments validated the finite element simulations as well as the feasibility of the kinematics. We developed a fabrication technique and made a sample to study the feasibility and applicability of the designed structure. Subsequently, we set up a finite element simulation that mirrors the prepared sample. A series of axial folding experiments were carried out to validate the FEM simulation. We have also derived kinematic formulations relating the structure's height, folding angle, and radius. To model and analyze the folding and unfolding mechanisms of this innovative structure, we employed Finite Element Analysis (FEA). In our study, we investigate four main geometric parameters that significantly influence our design's characteristics: crease thickness, number of stories, crease width, and number of vertexes in one story. By varying these design parameters, we systematically examine their impact on key structural attributes such as fatigue life, folding force, and energy absorption. Our findings indicate that reduced crease thickness correlates with lower von-Mises stress and strain, significantly extending the origami design's lifespan. Through our analysis, we identify specific parameter values that maximize fatigue life, ensuring the structural integrity and longevity of the design. Our findings show that increasing the crease width extends the fatigue life dramatically. In conclusion, we summarize the influence of each design parameter on the structure's behavioral characteristics in a comprehensive approach.

在本文中，我们介绍了一种新型圆柱形柔性结构，它结合了基于三浦-奥里模式的多层折纸和数学化运动学。我们的实验验证了有限元模拟以及运动学的可行性。我们开发了一种制作技术，并制作了一个样品来研究设计结构的可行性和适用性。随后，我们建立了一个与制备的样品相匹配的有限元模拟。为了验证有限元模拟，我们进行了一系列轴向折叠实验。我们还推导出了与结构高度、折叠角度和半径相关的运动学公式。为了模拟和分析这种创新结构的折叠和展开机制，我们采用了有限元分析法（FEA）。在研究中，我们调查了对设计特性有重大影响的四个主要几何参数：折痕厚度、层数、折痕宽度和一层中的顶点数量。通过改变这些设计参数，我们系统地研究了它们对疲劳寿命、折叠力和能量吸收等关键结构属性的影响。我们的研究结果表明，折痕厚度的减少与较低的 von-Mises 应力和应变相关，从而大大延长了折纸设计的使用寿命。通过分析，我们确定了能最大限度延长疲劳寿命的特定参数值，从而确保了设计的结构完整性和使用寿命。我们的研究结果表明，增加折痕宽度可显著延长疲劳寿命。最后，我们总结了每个设计参数对结构行为特征的影响，并提出了一种全面的方法。

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引用次数: 0

Numerical investigation on the blade vortex interaction noise reduction using higher harmonic control 利用高次谐波控制降低叶片涡流相互作用噪音的数值研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-29 DOI: 10.1016/j.ast.2024.109609

Tao Yang, Yan Ding, Xi Chen, Qijun Zhao

Accurately predicting the formation, evolution, and breakdown of helicopter blade tip vortex is crucial for simulating the Blade-Vortex Interaction (BVI) phenomenon. Firstly, the high-order Perturbed polynomial reconstructed Targeted Essentially Non-Oscillatory (TENO-P) scheme proposed by our research group is employed to improve the resolution of the helicopter rotor flowfield solver. The TENO-P scheme, building on the fifth-order TENO5 scheme, achieves one-order of accuracy improvement by adaptively adjusting the values of the free-parameter introduced by perturbed polynomial reconstruction. Subsequently, the AH-1 helicopter model rotor undergoing blade-vortex interaction is analyzed using the improved rotor flowfield solver and the Farassat-1A formula. The implementation of the TENO-P scheme notably enhances the resolution of the rotor flowfield solver in resolving the blade tip vortex structures, and the predicted noise results are in good agreement with the experimental data. Finally, the alteration of the BVI noise and its reduction mechanism of the AH-1 model rotor under different Higher Harmonic Controls (HHC) are analyzed. The findings show that the phase modulation margin increases with a decrease in harmonic order, and the noise reduction effect significantly improves as well. The negative component of the higher harmonic control is beneficial for reducing BVI noise while the positive component of the higher harmonic control exacerbates the BVI noise. The HHC reduces the collective pitch angle in the region where the tip vortex is about to be disturbed, decreasing the strength of the blade tip vortex in this region. This reduction weakens the strength of the parallel and near-parallel interaction on the advancing side, leads to the reduction of the positive peak impulsive of the BVI noise, and consequently lowers the intensity of the BVI noise.

准确预测直升机桨叶尖端涡旋的形成、演变和崩溃对于模拟桨叶-涡旋相互作用（BVI）现象至关重要。首先，我们的研究小组提出了高阶扰动多项式重构的目标基本非振荡（TENO-P）方案，以提高直升机旋翼流场求解器的分辨率。TENO-P 方案以五阶 TENO5 方案为基础，通过自适应调整扰动多项式重构引入的自由参数值，实现了一阶精度的提高。随后，使用改进的旋翼流场求解器和 Farassat-1A 公式分析了发生叶片-涡流相互作用的 AH-1 直升机模型旋翼。TENO-P 方案的实施显著提高了转子流场求解器对叶尖涡流结构的解析能力，预测的噪声结果与实验数据十分吻合。最后，分析了 AH-1 模型转子在不同高次谐波控制（HHC）下的 BVI 噪声变化及其降低机制。研究结果表明，相位调制裕度随着谐波阶数的降低而增加，降噪效果也显著提高。高次谐波控制的负分量有利于降低 BVI 噪声，而高次谐波控制的正分量则会加剧 BVI 噪声。在叶尖涡旋即将受到扰动的区域，高次谐波控制减小了集合俯仰角，从而降低了该区域的叶尖涡旋强度。这种减小削弱了前进侧平行和近平行相互作用的强度，导致 BVI 噪声的正峰值脉冲减小，从而降低了 BVI 噪声的强度。

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引用次数: 0

Numerical investigation of the distributed combustion in the thermal choked solid fuel combined cycle engine 热扼流固体燃料联合循环发动机分布式燃烧的数值研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-29 DOI: 10.1016/j.ast.2024.109635

Xiang Tang , Bo Zhang , Jiahang Li , Meng Huang , Xiaotao Tian , Yixiao Song

In this study, a solid fuel combined cycle engine concept based on the distributed combustion and the self-adaptive thermal choking is proposed, which can operate effectively within a wide Mach number range. By regulating the heat release through the distributed fuel injection, the thermal choking can be formed in the fixed geometry combustor. The air intake controls the flow capture and circulation area through the movement of its head cone, ensuring stable air breathing over a wide range. Numerical simulations conducted under Ma = 3.0 and 6.0 conditions using the validated Eulerian-Lagrangian method coupled with gaseous and particle reaction models demonstrate the concept's capability to operate within the Mach number range of 3.0–6.0, delivering improved mixing, combustion, and specific impulse performance.

本研究提出了一种基于分布式燃烧和自适应热扼流的固体燃料联合循环发动机概念，它可以在很宽的马赫数范围内有效运行。通过分布式燃料喷射调节热量释放，可在固定几何形状的燃烧器中形成热窒息。进气口通过其头部锥体的运动控制气流捕获和循环面积，确保在宽范围内稳定呼吸空气。在 Ma = 3.0 和 6.0 条件下，使用经过验证的欧拉-拉格朗日方法以及气态和颗粒反应模型进行的数值模拟表明，该概念能够在 3.0-6.0 马赫数范围内运行，并提供更好的混合、燃烧和比冲性能。

引用次数: 0

Enhanced support vector machine-based moving regression strategy for response prediction and reliability estimation of complex structure 基于支持向量机的移动回归增强策略，用于复杂结构的响应预测和可靠性估算

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-29 DOI: 10.1016/j.ast.2024.109634

Hui Zhu , Hui-Kun Hao , Cheng Lu

For predicting response property and estimating reliability level of complex structure, enhanced support vector machine-based moving regression (MR-ESVM) strategy is proposed based on support vector machine (SVM), heuristic algorithm and moving least square (MLS) technique. Under this strategy, we develop four different SVM models including SVM-based moving regression (MR-SVM), SVM-based improved moving regression (IMR-SVM), improved SVM-based moving regression (MR-ISVM) and bi-optimized SVM-based moving regression (BiOMR-SVM) methods. In these developed MR-ESVM approaches, the MR-SVM method is explored by introducing the MLS technique into the SVM model; the IMR-SVM method is discussed by fusing the MR-SVM method and artificial rabbits optimization (ARO), and the ARO is used to search the optimal radius of compact region; the MR-ISVM method is raised by integrating the ARO into the MR-SVM, and the ARO is applied to find the optimal values in the SVM model; The BiOMR-SVM method is emerged by merging the IMR-SVM and MR-ISVM methods. To verify the effectiveness of these developed MR-ESVM strategies, a multivariate nonlinear function approximation is implemented to illustrate the advantages from the mathematics perspective, an aeroengine turbine blisk radial deformation reliability analysis and an aircraft hydraulic system low pressure reliability analysis are derived to demonstrate the applicability in engineering practice. The analytical results show that these four MR-ESVM approaches hold excellent merits in modeling features and simulation characteristics. The efforts of this work provide a novel idea for the response prediction of complex structure, and enrich the reliability estimation principle of surrogate models of complex structure.

为了预测复杂结构的响应特性并估算其可靠性水平，我们在支持向量机（SVM）、启发式算法和移动最小平方（MLS）技术的基础上提出了基于支持向量机的增强移动回归（MR-ESVM）策略。在这一策略下，我们开发了四种不同的 SVM 模型，包括基于 SVM 的移动回归（MR-SVM）、基于 SVM 的改进移动回归（IMR-SVM）、基于 SVM 的改进移动回归（MR-ISVM）和基于 SVM 的双优化移动回归（BiOMR-SVM）方法。在这些已开发的 MR-ESVM 方法中，MR-SVM 方法是通过在 SVM 模型中引入 MLS 技术来进行探索的；IMR-SVM 方法是通过将 MR-SVM 方法与人工兔子优化（ARO）相融合来进行讨论的，ARO 用于搜索紧凑区域的最佳半径；通过将 ARO 融入 MR-SVM 方法，提出了 MR-ISVM 方法，并应用 ARO 寻找 SVM 模型中的最优值；通过合并 IMR-SVM 和 MR-ISVM 方法，提出了 BiOMR-SVM 方法。为了验证所开发的 MR-ESVM 策略的有效性，实现了多变量非线性函数逼近，从数学角度说明了其优势；得出了航空发动机涡轮叶盘径向变形可靠性分析和飞机液压系统低压可靠性分析，证明了其在工程实践中的适用性。分析结果表明，这四种 MR-ESVM 方法在建模特征和仿真特性方面都具有很好的优点。这些研究成果为复杂结构的响应预测提供了新的思路，丰富了复杂结构代用模型的可靠性估算原理。

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引用次数: 0

Impulsive maneuver strategy for multi-agent orbital pursuit-evasion game under sparse rewards 稀疏奖励下多代理轨道追逐-逃避博弈的冲动机动策略

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-29 DOI: 10.1016/j.ast.2024.109618

Hongbo Wang, Yao Zhang

To address the subjectivity of dense reward designs for the orbital pursuit-evasion game with multiple optimization objectives, this paper proposes the reinforcement learning method with a hierarchical network structure to guide game strategies under sparse rewards. Initially, to overcome the convergence challenges in the reinforcement learning training process under sparse rewards, a hierarchical network structure is proposed based on the hindsight experience replay. Subsequently, considering the strict constraints imposed by orbital dynamics on spacecraft state space, the reachable domain method is introduced to refine the subgoal space in the hierarchical network, further facilitating the achievement of subgoals. Finally, by adopting the centralized training-layered execution approach, a complete multi-agent reinforcement learning method with the hierarchical network structure is established, enabling networks at each level to learn effectively in parallel within sparse reward environments. Numerical simulations indicate that, under the single-agent reinforcement learning framework, the proposed method exhibits superior stability in the late training stage and enhances exploration efficiency in the early stage by 38.89% to 55.56% to the baseline method. Under the multi-agent reinforcement learning framework, as the relative distance decreases, the subgoals generated by the hierarchical network transition from long-term to short-term, aligning with human behavioral logic.

针对具有多重优化目标的轨道追逐-逃避博弈中密集奖励设计的主观性，本文提出了具有分层网络结构的强化学习方法，以指导稀疏奖励下的博弈策略。首先，为了克服稀疏奖励下强化学习训练过程中的收敛难题，本文提出了一种基于事后经验回放的分层网络结构。随后，考虑到轨道动力学对航天器状态空间的严格约束，引入可达域方法来细化分层网络中的子目标空间，进一步促进子目标的实现。最后，通过采用集中训练-分层执行的方法，建立了具有分层网络结构的完整的多代理强化学习方法，使各层次网络在稀疏奖励环境中有效地并行学习。数值模拟表明，在单代理强化学习框架下，所提出的方法在后期训练阶段表现出卓越的稳定性，在早期阶段的探索效率比基线方法提高了 38.89% 至 55.56%。在多代理强化学习框架下，随着相对距离的减小，分层网络生成的子目标会从长期过渡到短期，符合人类的行为逻辑。

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引用次数: 0

Experimental investigation of non-synchronous vibration and its mechanism analysis by using a cantilever beam-like compressor cascade 利用悬臂梁式压缩机级联的非同步振动实验研究及其机理分析

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-29 DOI: 10.1016/j.ast.2024.109626

Chunlong Tan , Hangshan Gao , Lei Li , Yuxin Huo

With the increasement of unsteady load and the extensive utilization of light-weight material, compressor blade is encountering increasingly serious flow induced vibration problems. Among which, non-synchronous vibration (NSV) has received special attention due to its complex generation mechanism and significant impact on high cycle fatigue. To better understand the physical mechanism causing NSV in compressor, this study designed a cantilever beam-like compressor cascade and made a detailed investigation about its flow separation induced vibration by means of experimental and numerical methods. The experiments were conducted at 9 engine representative conditions and the data of both on-blade pressure and structural response were measured simultaneously. Results show that, the effect of Ma number on the dynamic response will increase with the increasement of incidence angle and there is a strong nonlinearity. The effect of incidence angle on the dynamic response shows obvious bifurcation phenomenon. The results of large eddy simulation (LES) further reveal that the obvious characteristics of the dynamic response are caused by the laminar separation bubble (LSB) of suction surface, and the periodic separation and reattachment of boundary layer provides initial excitation sources for NSV. The unsteady excitation acts on blades in the form of energy and then forces the blades to vibrate with low order modes. The vibration amplitudes are closely related to the separation points and increase as the separation points move forward.

随着非稳定载荷的增加和轻质材料的广泛应用，压缩机叶片遇到了越来越严重的流动诱导振动问题。其中，非同步振动（NSV）因其复杂的产生机理和对高循环疲劳的重大影响而受到特别关注。为了更好地理解压缩机非同步振动的物理机制，本研究设计了一个类似悬臂梁的压缩机级联，并通过实验和数值方法对其流动分离诱导振动进行了详细研究。实验在 9 种具有代表性的发动机工况下进行，同时测量了叶片压力和结构响应数据。结果表明，马氏数对动态响应的影响会随着入射角的增大而增大，并且存在很强的非线性。入射角对动态响应的影响表现出明显的分叉现象。大涡度模拟（LES）结果进一步表明，动态响应的明显特征是由吸力面的层状分离气泡（LSB）引起的，边界层的周期性分离和重新附着为 NSV 提供了初始激励源。非稳定激励以能量形式作用于叶片，然后迫使叶片以低阶模态振动。振动振幅与分离点密切相关，并随着分离点的前移而增大。

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引用次数: 0

Research on the aerodynamic characteristics of electrically controlled rotor under Parallel Blade Vortex Interaction using Lattice Boltzmann Method 利用格子波尔兹曼法研究平行叶片涡流相互作用下电控转子的气动特性

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-28 DOI: 10.1016/j.ast.2024.109631

Lingzhi Wang , Taoyong Su , Kewei Li , Bonan Zhao

An electrically controlled rotor (ECR), also known as a swashplateless rotor, employs a trailing edge flap (TEF) system for primary rotor control instead of a swashplate, demonstrating the significant potential in rotor vibration and noise reduction. To investigate the aerodynamic characteristics of the blade flap segment of the ECR under parallel blade vortex interaction, an aerodynamic analysis model based on the lattice Boltzmann method (LBM) is established using the D3Q27 lattice model. The model is validated against experimental data of both the airfoil with trailing edge flap and conventional airfoil under vortex interaction, showing that the LBM can effectively predict variations in aerodynamic loads under both conditions. Based on this model, the effects of different flap deflection angles and miss distances on the aerodynamic characteristics of the ECR under parallel BVI are analyzed. The results indicate that under strong vortex interaction, a region of flow separation forms due to the entrainment effect of the vortex and adverse pressure gradient. The small-scale vortex structure upstream of the flap can also be observed and is believed to contribute to the unsteady flow phenomena such as vortex structure splitting, development, and separation on the upper surface of the flap. The different flap deflection angles mainly affect the scale and type of vortex structures developed on the flap upper surface. As the miss distance increases, the interaction effect is significantly weakened compared to strong vortex interaction. However, as the vortex moves downstream along the airfoil lower surface, it entrains vorticity from the lower surface, ultimately forming a negative pressure region on the lower surface of the flap. The different flap deflection angles will influence the structural characteristics during the downstream motion of the vortex, which changes the size of the negative pressure region, causing differences in the magnitude of the variations in aerodynamic parameters.

电控转子（ECR）又称无斜盘转子，它采用后缘襟翼（TEF）系统代替斜盘进行主转子控制，在减少转子振动和噪音方面具有巨大潜力。为了研究平行叶片涡流相互作用下 ECR 叶片襟翼部分的气动特性，使用 D3Q27 晶格模型建立了基于晶格玻尔兹曼法（LBM）的气动分析模型。该模型根据涡流相互作用下带后缘襟翼的机翼和传统机翼的实验数据进行了验证，结果表明 LBM 可以有效预测这两种条件下的气动载荷变化。基于该模型，分析了不同襟翼偏转角和失误距离对平行 BVI 条件下 ECR 气动特性的影响。结果表明，在强涡流相互作用下，由于涡流的夹带效应和不利的压力梯度，会形成一个气流分离区域。襟翼上游的小尺度涡旋结构也可以被观察到，并被认为是襟翼上表面涡旋结构分裂、发展和分离等非稳态流动现象的原因。不同的襟翼偏转角主要影响襟翼上表面形成的涡流结构的规模和类型。随着偏离距离的增加，与强涡流相互作用相比，相互作用效果明显减弱。然而，当涡流沿机翼下表面向下游移动时，会夹带下表面的涡流，最终在襟翼下表面形成负压区。不同的襟翼偏转角度会影响涡流顺流运动时的结构特性，从而改变负压区的大小，造成气动参数变化幅度的差异。

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引用次数: 0

Energy absorption of auxetic honeycomb with graded beam thickness based on Bezier curve 基于贝塞尔曲线的梁厚度分级辅助蜂窝的能量吸收

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-28 DOI: 10.1016/j.ast.2024.109619

Jianzhong Zhou , Yifan Wang , Huichen Luo , Guanghua Zhao , Jie Chen , Yingying Cui , Liangmo Wang , Qiang Gao , Xiaoyu Wang

In order to improve the energy absorption and lightweight of the structure, a novel auxetic honeycomb with graded beam thickness based on Bezier curve (BZH) is proposed on the basis of the double arrow negative Poisson ratio honeycomb. The finite element model of BZH under axial compression is established, and its accuracy is verified by experiments. Compared with a honeycomb of uniform beam thickness (DUH) of the same mass, the thickness of the beam becomes thicker in the middle and thinner on both sides, which causes the BZH to produce more plastic hinges when compressed, and the energy absorption is increased by 12 %. By parameter analysis of beam thickness distribution trend, the mechanical properties of BZH can be effectively controlled. A theoretical model of BZH under quasi-static compression is also established and the BZH configuration is optimized by proxy modeling technique and NSGA-II algorithm. The results show that the SEA of the optimized structure is increased from 5.23 kJ·kg^-1 to 6.17 kJ·kg^-1, and the energy efficiency is reduced from 3.44 kN to 2.96 kN. Therefore, auxetic honeycomb with graded beam thickness based on Bezier curve has great potential in the field of energy absorption.

为了提高结构的能量吸收能力和轻质性，在双箭负泊松比蜂窝的基础上，提出了一种基于贝塞尔曲线的新型分级梁厚辅助蜂窝（BZH）。建立了轴向压缩下 BZH 的有限元模型，并通过实验验证了其准确性。与相同质量的均匀梁厚蜂窝（DUH）相比，梁的厚度中部变厚，两侧变薄，这使得 BZH 在受压时产生更多的塑性铰，能量吸收增加了 12%。通过对梁厚度分布趋势的参数分析，可以有效控制 BZH 的力学性能。此外，还建立了准静态压缩下 BZH 的理论模型，并通过代理建模技术和 NSGA-II 算法对 BZH 配置进行了优化。结果表明，优化结构的 SEA 从 5.23 kJ-kg-1 增加到 6.17 kJ-kg-1，能效从 3.44 kN 降低到 2.96 kN。因此，基于贝塞尔曲线的分级梁厚度辅助蜂窝在能量吸收领域具有巨大潜力。

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引用次数: 0

Differential-algebraic equation-based model predictive control for trajectory tracking of spacecraft-mounted continuum manipulators 基于微分代数方程的模型预测控制，用于航天器安装的连续机械手的轨迹跟踪

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-09-28 DOI: 10.1016/j.ast.2024.109615

Jinzhao Yang , Haijun Peng , Shunan Wu , Jie Zhang , Zhigang Wu , Jianing Wu

Spacecraft-mounted continuum manipulators (SMCMs) exhibit great potential for performing dexterous operations in unstructured environments due to their inherent compliance and dexterity. However, the dynamic model of the rigid-flexible coupling SMCM is highly nonlinear and typically formulated as a set of implicit differential-algebraic equations (DAEs), posing significant challenges for precise trajectory tracking control. This paper proposes a novel model predictive control (MPC) framework specifically designed for generic DAEs to achieve precise trajectory tracking of the SMCM under uncertain disturbances and input limitations. The DAE model of the SMCM is discretized into a set of nonlinear algebraic equations. By performing implicit differentiation of these equations with respect to the system state, the state transition matrix (STM) for the DAE model is derived. The optimal control action for the SMCM can be further determined based on the derived STM. Additionally, nonlinear complementary functions are introduced to address the issue of input limitations, allowing the problem of determining the optimal control sequence to be equivalently transformed into a set of nonlinear algebraic equations for solving. Numerical simulations demonstrate that the proposed approach can achieve precise trajectory tracking of the SMCM while strictly adhering to input limitations.

由于其固有的顺应性和灵巧性，航天器安装的连续机械手（SMCM）在非结构化环境中执行灵巧操作方面展现出巨大的潜力。然而，刚柔耦合 SMCM 的动态模型高度非线性，通常表述为一组隐式微分代数方程 (DAE)，给精确轨迹跟踪控制带来了巨大挑战。本文提出了一种专为通用 DAE 设计的新型模型预测控制 (MPC) 框架，以在不确定干扰和输入限制条件下实现 SMCM 的精确轨迹跟踪。SMCM 的 DAE 模型被离散化为一组非线性代数方程。通过对这些方程进行与系统状态相关的隐式微分，得出了 DAE 模型的状态转换矩阵 (STM)。根据推导出的 STM，可以进一步确定 SMCM 的最优控制动作。此外，还引入了非线性互补函数来解决输入限制问题，从而将确定最优控制序列的问题等效地转化为一组非线性代数方程来求解。数值模拟证明，所提出的方法可以实现 SMCM 的精确轨迹跟踪，同时严格遵守输入限制。

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引用次数: 0