Mechanism and Machine Theory最新文献

Design and analysis of modular array deployable antenna mechanism based on one Waterbomb-Ori and four Miura-Ori basic unit mechanism 基于1个水弹- ori和4个Miura-Ori基本单元机构的模块化阵列展开天线机构设计与分析

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-02-05 DOI: 10.1016/j.mechmachtheory.2026.106372

Yan Wang, Yuantu Duan, Hui Yang

The advancement of the aerospace industry necessitates the implementation of deployable space mechanisms. Spaceborne planar antennas must exhibit high stiffness, exceptional precision, and robust stability to withstand the harsh conditions of the space environment. This research introduces the design of the modular array deployable antenna (MADA) mechanism. A multi-vertex hybrid crease basic unit with three degrees of freedom (DoFs) is developed, consisting of one Waterbomb-Origami (Waterbomb-Ori) basic unit and four Miura-Origami (Miura-Ori) basic units (1W4M). Employing thick-panel origami theory, a zero-thickness model of the 1W4M crease basic unit is systematically constructed. Based on this model, the MADA mechanism is proposed. A kinematic model of the MADA mechanism is derived using the closed vector method. The theoretical results are validated through simulation studies. A dynamic model of the MADA mechanism is established, and the deployment process is optimized according to mechanism equilibrium theory to improve operational stability. Finally, a prototype of the MADA mechanism is fabricated, and agreement between real models and numerical simulations demonstrates the ability of the proposed methodology to confirm its practical feasibility.

航空航天工业的发展需要实施可展开的空间机制。星载平面天线必须具有高刚度、超高精度和强大的稳定性，以承受恶劣的空间环境条件。介绍了模块化阵列可展开天线（MADA）机构的设计。提出了一种三自由度的多顶点混合折痕基本单元，由1个Waterbomb-Origami （Waterbomb-Ori）基本单元和4个Miura-Origami （Miura-Ori）基本单元（1W4M）组成。运用厚板折纸理论，系统构建了1W4M折痕基本单元的零厚度模型。基于该模型，提出了MADA机制。采用闭向量法建立了MADA机构的运动模型。通过仿真研究验证了理论结果。建立了MADA机制的动态模型，并根据机制均衡理论对部署过程进行了优化，提高了运行稳定性。最后，制作了MADA机构的原型，实际模型与数值模拟结果吻合，验证了所提方法的实际可行性。

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引用次数: 0

The effect of external load on multi-point contact transitions of three-point angular contact ball bearing 外载荷对三点角接触球轴承多点接触过渡的影响

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-30 DOI: 10.1016/j.mechmachtheory.2026.106368

Siqi Guo , Wenzhong Wang , Rui Tang , He Liang , Haibo Zhang

As a critical supporting component of aero-engine main shafts, the three-point angular contact ball bearing (TPACBB) is subjected to complex external loads, leading to time-varying contact characteristics that significantly influence its dynamic behavior and service life. This study establishes a universal, nonlinear, multi-degree-of-freedom dynamic model applicable to TPACBB. It employs the Lankarani-Nikravesh model for more accurate contact force calculation and comprehensively accounts for the interactions among the balls, cage, raceways, and lubricant. The relationship between axial/radial loads and multi-point contact states is investigated, and the dynamic performance under different contact conditions is analyzed. Additionally, the critical load ratio inducing multi-point contact variations is determined under varying loading conditions and structural parameters. The results reveal that the critical axial-to-radial load ratio governing the transition between three-point and two-point contact depends on the bearing's structural parameters. Specifically, the shim angle exhibits a positive correlation with the critical load ratio, whereas the inner raceway groove radius demonstrates a negative correlation. This research provides valuable insights for the structural optimization and fault diagnosis of TPACBB.

三点角接触球轴承（TPACBB）作为航空发动机主轴的关键支承部件，其接触特性随时间变化，受到复杂的外部载荷的影响，对其动力性能和使用寿命产生重大影响。本研究建立了适用于TPACBB的通用、非线性、多自由度动力学模型。它采用Lankarani-Nikravesh模型进行更精确的接触力计算，并综合考虑了球、保持架、滚道和润滑剂之间的相互作用。研究了轴向/径向载荷与多点接触状态的关系，分析了不同接触条件下的动态性能。此外，在不同的载荷条件和结构参数下，确定了引起多点接触变化的临界载荷比。结果表明，控制三点接触和两点接触过渡的临界轴向径向载荷比取决于轴承的结构参数。其中，垫片角与临界载荷比呈正相关，而内滚道槽半径呈负相关。该研究为TPACBB的结构优化和故障诊断提供了有价值的见解。

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引用次数: 0

Nonlinearity separation and static-dynamic synthesis: A rapid and accurate algorithm for gear dynamics 非线性分离与静动综合：一种快速准确的齿轮动力学算法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-29 DOI: 10.1016/j.mechmachtheory.2026.106367

Yifan Huangfu , Xingjian Dong , Juanjuan Shi , Zhongkui Zhu

Achieving faster computational efficiency in gear dynamic simulation remains a critical challenge due to the strong localized nonlinearities inherent in these systems. In this work, a nonlinearity separation and static-dynamic synthesis (NSSDS) method is proposed to isolate localized nonlinearities at gear and bearing interfaces. NSSDS pioneers the application of a static-dynamic synthesis basis for model order reduction and effectively combines static deformation characteristics with dynamic modal information to accelerate gear dynamic calculation substantially while preserving accuracy in capturing nonlinear behaviors. Both the numerical simulation and experimental studies demonstrate the accuracy and computational efficiency of NSSDS. Nonlinear dynamic analysis shows that NSSDS effectively captures the dominant static deformation in geared rotor systems, enabling highly efficient and accurate dynamic analysis with considerably reduced truncation orders. NSSDS outperforms the traditional mode superposition method by incorporating static deformation characteristics. So it is particularly suitable for rapid vibration simulation of complex nonlinear gear systems. This fast algorithm provides rapid, accurate simulation of complex nonlinear behavior, which is crucial for vibration analysis and dynamic design optimization of gear transmission systems.

由于这些系统中固有的强局部非线性，在齿轮动态仿真中实现更快的计算效率仍然是一个关键的挑战。在这项工作中，提出了一种非线性分离和静动态综合（NSSDS）方法来隔离齿轮和轴承界面的局部非线性。NSSDS率先应用静动态综合基础进行模型降阶，有效地将静态变形特征与动态模态信息相结合，大大加快了齿轮动态计算速度，同时保持了捕获非线性行为的准确性。数值模拟和实验研究都证明了NSSDS的准确性和计算效率。非线性动力学分析表明，NSSDS有效地捕获了齿轮传动转子系统的主要静态变形，从而在大大减少截断阶数的情况下实现了高效准确的动态分析。NSSDS结合了静态变形特性，优于传统的模态叠加方法。特别适用于复杂非线性齿轮系统的快速振动仿真。该算法能够快速、准确地模拟齿轮传动系统的复杂非线性行为，对齿轮传动系统的振动分析和动态设计优化具有重要意义。

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引用次数: 0

A multi-objective parameter updating method for high-fidelity dynamic modeling of gear transmission systems 齿轮传动系统高保真动力学建模的多目标参数更新方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-27 DOI: 10.1016/j.mechmachtheory.2026.106366

Caizi Fan , Hui Ma , Yongchao Zhang , Hong Guan , Jiaqi Liu , Chao Zhao , Tianyu Zhao , Zhijun Li

Dynamic models are widely used due to their strong interpretability and physical consistency, making them effective tools for analyzing and predicting system behavior. A high-fidelity dynamic model can accurately represent the system’s dynamic response. However, many existing approaches depend on idealized assumptions, which often cause notable discrepancies between simulated and measured vibration responses. Moreover, most current optimization methods emphasize time-domain features, while the role of frequency-domain characteristics remains insufficiently explored. Therefore, this paper presents a parameter updating approach for the dynamic model, aiming to improve model fidelity and predictive reliability. First, a dynamic model of the gear transmission system is established based on the finite element method. Nonlinear excitations such as geometric eccentricity and gear backlash are introduced to improve model accuracy. Sensitivity analysis is then conducted to identify the key parameters influencing the system’s dynamic response. Finally, a multi-objective optimization of these key parameters is performed using the NSGA-II. Experimental validation on a single-stage gear test rig demonstrates the effectiveness and practicality of the proposed approach in reducing response discrepancies and improving model accuracy.

动态模型由于具有较强的可解释性和物理一致性而被广泛应用，是分析和预测系统行为的有效工具。高保真的动态模型可以准确地表示系统的动态响应。然而，许多现有的方法依赖于理想化的假设，这通常会导致模拟和测量振动响应之间的显着差异。此外，目前大多数优化方法都强调时域特征，而频域特征的作用还没有得到充分的探讨。为此，本文提出了一种动态模型的参数更新方法，旨在提高模型保真度和预测可靠性。首先，基于有限元法建立了齿轮传动系统的动力学模型。为了提高模型精度，引入了几何偏心和齿轮间隙等非线性激励。然后进行灵敏度分析，找出影响系统动态响应的关键参数。最后，利用NSGA-II算法对这些关键参数进行多目标优化。在单级齿轮试验台上的实验验证表明了该方法在减小响应误差和提高模型精度方面的有效性和实用性。

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引用次数: 0

Integrating the elastic surroundings into multibody simulation of rolling bearings 将弹性环境融入滚动轴承多体仿真

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-22 DOI: 10.1016/j.mechmachtheory.2026.106365

Tobias Baumann , Bodo Hahn , Stephan Tremmel

Rolling bearings provide secure guidance and load transmission only with sufficient support from the surrounding components (housing, gear body, shaft). In some cases, such as planetary gear bearings or large-size bearings, the stiffness of the bearing surroundings can affect the internal bearing dynamics. Therefore, this article presents a new, computationally efficient method for integrating elastic surroundings, including the rings, into multibody simulation of rolling bearings. Elastic modeling is based on a component mode synthesis method and the floating frame of reference formulation. For the contact calculation between rolling element and ring, a slice model is extended to deformed ring surfaces. The method is applied to spherical roller bearings. Minor mean errors of <4% in the load distribution verify the implemented contact search and force calculation. Additional evaluations of the rolling element speed confirm the correct kinematics of the rolling elements. A plummer block housing demonstrates that the method can account for inhomogeneous stiffness distributions and is not restricted to simple, symmetrical surroundings. Furthermore, it was found that outer ring deformations can lead to increased bearing vibrations.

滚动轴承只有在周围部件（壳体、齿轮体、轴）提供足够支撑的情况下才能提供安全的导向和负载传输。在某些情况下，如行星齿轮轴承或大尺寸轴承，轴承周围的刚度会影响轴承内部动力学。因此，本文提出了一种新的、计算效率高的方法，将包括环在内的弹性环境整合到滚动轴承的多体仿真中。弹性建模是基于构件模态综合方法和浮动框架的参考公式。对于滚动体与环的接触计算，将切片模型推广到变形环的表面。该方法应用于球面滚子轴承。在载荷分布中有4%的微小平均误差，验证了所实现的接触搜索和力计算。对滚动体速度的附加评估确认了滚动体的正确运动学。一个plummer block外壳表明，该方法可以解释不均匀的刚度分布，而不限于简单的，对称的环境。此外，还发现外圈变形会导致轴承振动增加。

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引用次数: 0

Towards realistic simulation of two-stroke marine engines: A floating frame approach 面向二冲程船用发动机的真实仿真：一种浮动框架方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-22 DOI: 10.1016/j.mechmachtheory.2025.106318

Jacob Østerby Rasmussen , Anders Vølund , Ilmar Santos

This paper presents a novel multi-body simulation framework utilizing the nodal-based Floating Frame of Reference Formulation to realistically model large-bore two-stroke marine engines. The framework employs linear model order reduction to condense finite element models of the crankshaft, shafting system, and housing, and uses specialized deformation modes that efficiently model the fluid-solid interaction in main bearings for time-domain elastohydrodynamic simulations. The framework is implemented in a custom-built multi-body code in MATLAB and the paper explains implementation details allowing other researchers to replicate the approach using the nodal-based Floating Frame of Reference Formulation. Balancing computational efficiency and fidelity, it accurately represents the coupled engine system’s dynamic response. Validated against experimental data from a full-scale four-cylinder test engine, simulated journal orbits and journal misalignments show strong agreement across the engine’s operating range. Evaluation of two case studies, representing distinct engine configurations, compares main journal dynamics and torsional frequency responses, demonstrating the framework’s versatility and robustness in capturing global engine dynamics.

本文提出了一种新的多体仿真框架，利用基于节点的浮动参考框架公式对大缸径二冲程船用发动机进行仿真。该框架采用线性模型降阶来压缩曲轴、轴系和轴承座的有限元模型，并使用专门的变形模式，有效地模拟主轴承的流固相互作用，进行时域弹性流体动力学仿真。该框架在MATLAB中以定制的多体代码实现，本文解释了实现细节，允许其他研究人员使用基于节点的浮动参考框架公式复制该方法。它平衡了计算效率和保真度，准确地反映了耦合发动机系统的动态响应。根据全尺寸四缸测试发动机的实验数据进行验证，模拟的轴颈轨道和轴颈错位在发动机的工作范围内显示出很强的一致性。对代表不同发动机配置的两个案例进行了评估，比较了主轴颈动态和扭转频率响应，证明了该框架在捕获全局发动机动态方面的通用性和鲁棒性。

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引用次数: 0

Design and analysis method of a cubical deformable mobile mechanism based on URU chains 基于URU链的立方体可变形移动机构的设计与分析方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-22 DOI: 10.1016/j.mechmachtheory.2026.106362

Ziming Zhao , Yezhuo Li , Jian S Dai , Jianxu Wu , Yan-an Yao , Peng Jin , Zibin Wang

The purpose of this paper is to put forward a novel cubical deformable mobile mechanism with URU chains. This new mobile mechanism with the external cube shape is composed of eight platforms and twelve URU chains. A unified analytical method is proposed for the analysis of the degree of freedoms (DoFs) and kinematics of this kind of mechanism. The DoFs are obtained based on screw theory. The coordinates of points are obtained through homogeneous transformation matrixes and closed-loop equations. Meanwhile, the results of DoFs analysis in each chain are used to find and verify the number of constraint equations. Furthermore, the workspaces of the center of mass (CM), platforms, chains, and loops of the mechanism are solved, the results of which are used to design a tracked-rolling gait. A series of dynamic simulations are conducted and analyzed to test the performance of the mechanism, including the verification of its folding, tracked-rolling, climbing capability spheroidal-rolling capability, and the climbing capability in vertical cracks. An experimental prototype is fabricated and constructed to verify the motion capability and the tracked-rolling gait.

本文的目的是提出一种新型的带URU链的立方体可变形移动机构。这种具有外部立方体形状的新型移动机构由8个平台和12个URU链组成。提出了一种统一的分析该类机构自由度和运动学的分析方法。根据螺旋理论得到了自由度。通过齐次变换矩阵和闭环方程得到各点的坐标。同时，利用各链的自由度分析结果，找出并验证约束方程的个数。在此基础上，求解了机构的质心、平台、链条和环的工作空间，并将求解结果用于轨迹滚动步态的设计。对该机构进行了一系列动力学仿真分析，验证了机构的折叠性能、轨迹滚动性能、爬坡能力、球滚能力和垂直裂纹爬坡能力。制作并搭建了实验样机，验证了机器人的运动能力和跟踪滚动步态。

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引用次数: 0

Obtaining selectable optimal configurations in compliant mechanisms through mapping of load characteristics with higher-order Bézier curves 通过负载特性与高阶bsamzier曲线的映射，获得柔性机构可选择的最优构型

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-19 DOI: 10.1016/j.mechmachtheory.2026.106363

Zhenfeng Wu , Jierong Li , Rixin Wang , Yang Shen , Xianmin Zhang , Hai Li , Andrés Kecskeméthy , Benliang Zhu

This paper aims to address the challenge of configuration selection for quantitative load output in compliant mechanisms. It generalizes the chained beam constraint model (CBCM) based on high-order Bézier curves and establishes a beam shape optimization model for load characteristics, further obtaining configuration atlases suitable for active selection that correspond to Bézier curves of different orders. Additionally, the study proposes an adaptive node division strategy to ensure model accuracy, derives the gradient information of the CBCM to improve computational efficiency, and clarifies the dimensionality reduction conditions for applying the proposed model to optimization problems. On this basis, it conducts optimization analyses for global and local intervals respectively, targeting linear output and constant output objectives. Rotational hinges and translational hinges are used as case studies, and the accuracy and effectiveness of the proposed method are fully verified through simulations and experiments. Finally, the method is applied to humanoid dexterous finger joint configurations with narrow design spaces, completing application verification for variable-stiffness joint design. This demonstrates the method’s engineering practicality and value, supporting compliant mechanism compatibility design.

本文旨在解决柔性机构中定量负荷输出配置选择的挑战。推广了基于高阶bsamzier曲线的链梁约束模型（CBCM），建立了梁形荷载特性优化模型，得到了不同阶bsamzier曲线对应的适合主动选择的构型图集。此外，提出了自适应节点划分策略以保证模型的准确性，导出了CBCM的梯度信息以提高计算效率，并明确了将所提模型应用于优化问题的降维条件。在此基础上，分别针对线性输出目标和恒定输出目标，对全局区间和局部区间进行优化分析。以旋转铰链和平动铰链为例，通过仿真和实验充分验证了所提方法的准确性和有效性。最后，将该方法应用于设计空间较窄的仿人灵巧手指关节构型，完成变刚度关节设计的应用验证。验证了该方法的工程实用性和价值，为柔性机构的兼容性设计提供了支持。

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引用次数: 0

ATSMR: A new matrix-based remaining useful life prediction method for roller bearing 基于矩阵的滚动轴承剩余使用寿命预测新方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-19 DOI: 10.1016/j.mechmachtheory.2026.106364

Anbo Tang, Haiyang Pan, Jinyu Tong

As a classical regression analysis method, support vector regression (SVR) is extensively employed within the realm of remaining useful life (RUL) prediction. However, SVR requires feature vectors as the input, which makes it easy for information to leak during the process of constructing feature vectors. To address this problem, a novel matrix-based regressor is proposed in this paper, called asymmetric twin support matrix regression (ATSMR). In ATSMR, a novel rescaled asymmetric term and asymmetric tube are constructed, which imposes corresponding penalties according to the sample location and can achieve advanced prediction. Meantime, an improved neighborhood graph is combined with the matrix-based regressor, which considers the number of data clusters to more accurately construct the internal geometric structure of the original data. The efficacy and advantage of the proposed method are confirmed through experimental validation on two datasets, and the experimental outcomes reveal that the proposed method maintains high prediction accuracy and stability in the RUL prediction of roller bearing.

支持向量回归作为一种经典的回归分析方法，在剩余使用寿命预测领域得到了广泛的应用。然而，SVR需要特征向量作为输入，这使得在构造特征向量的过程中容易出现信息泄漏。为了解决这一问题，本文提出了一种新的基于矩阵的回归器，称为非对称双支持矩阵回归（ATSMR）。在ATSMR中，构造了一种新的重新标度的非对称项和非对称管，根据样本位置施加相应的惩罚，可以实现超前预测。同时，将改进的邻域图与基于矩阵的回归量相结合，考虑数据簇的数量，更准确地构建原始数据的内部几何结构。通过在两个数据集上的实验验证，验证了所提方法的有效性和优势，实验结果表明，所提方法在滚动轴承RUL预测中保持了较高的预测精度和稳定性。

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引用次数: 0

An efficient data-driven framework of hybrid dynamics for real-time modeling and control of continuum robots 连续体机器人实时建模与控制的高效数据驱动混合动力学框架

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-16 DOI: 10.1016/j.mechmachtheory.2026.106361

Yuhang Liu , Kai Luo , Qiang Tian , Haiyan Hu

Continuum robots exhibit exceptional compliance and adaptability. However, their intrinsic nonlinear dynamics poses significant challenges for real-time control under dynamic conditions. This paper presents a new data-driven framework of hybrid dynamics (HD) for modeling and control of continuum robots. This framework decomposes the nonlinear dynamics of a continuum robot into the nonlinear statics of global deformation and the linear dynamics of relative vibration, and leads to two sub-models of global deformation statics (GDS) and relative motion dynamics (RMD) via different data-driven approaches. The first sub-model uses a deep neural network to predict nonlinear static deformations, while the second sub-model utilizes dynamics mode decomposition for relative vibration compensation. The nonlinear integration of the two sub-models establishes the physics-embedded data-driven model with reduced complexity. Combining quasi-static positioning and model-predictive vibration suppression leads to design of a hierarchical dynamic controller. The experiments of a cable-driven continuum robot demonstrate precise trajectory tracking and effective vibration suppression under payload and high-speed conditions. This data-driven modeling and control framework balances computational efficiency and control performance, enabling practical advances of continuum robots under complex working scenarios.

Continuum机器人表现出卓越的顺应性和适应性。然而，它们固有的非线性动力学特性给动态条件下的实时控制带来了巨大的挑战。提出了一种新的数据驱动混合动力学框架，用于连续体机器人的建模和控制。该框架将连续体机器人的非线性动力学分解为全局变形的非线性静力学和相对振动的线性动力学，并通过不同的数据驱动方法得到全局变形静力学（GDS）和相对运动动力学（RMD）两个子模型。第一个子模型使用深度神经网络预测非线性静态变形，第二个子模型使用动态模态分解进行相对振动补偿。两个子模型的非线性集成建立了物理嵌入的数据驱动模型，降低了模型的复杂度。将准静态定位与模型预测振动抑制相结合，设计了层次动态控制器。索驱动连续体机器人在载荷和高速条件下进行了精确的轨迹跟踪和有效的振动抑制实验。这种数据驱动的建模和控制框架平衡了计算效率和控制性能，使连续体机器人在复杂工作场景下的实际进展成为可能。

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引用次数: 0