Mechanism and Machine Theory最新文献_第2页

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 : 2026-04-01 Epub 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

Load-based iterative modification design method for face gear pairs 基于载荷的面齿轮副迭代修形设计方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-02-02 DOI: 10.1016/j.mechmachtheory.2026.106369

Wentao Liu , Zehua Hu , Jinyuan Tang , Zhou Sun , Zhaoyang Tian , Heng Ouyang , Dongqi Chen , Zhiwei Wang

Edge contact, a common and highly detrimental issue in gear transmissions, significantly degrades gear performance and service life. Point-contact face gear (FG) pairs are particularly susceptible to this issue,as the mating spur gears have 1–3 fewer teeth than the generating gears. To address this problem, a novel load-based iterative modification design method is presented for FG pairs. First, modified FGs are designed using a modified generating gear to determine initial modification parameters, and the potential contact lines of the FG pairs are subsequently determined. Subsequently, loaded contact parameters, including contact patterns, load distribution ratios, and time-varying meshing stiffness (TVMS), are determined according to the load to assess the meshing state. Based on this analysis, the modification parameters are iteratively adjusted in a closed-loop design cycle. Ultimately, the derived modification parameters eliminate edge contact while maintaining stable contact patterns even under 120% of the rated load or installation errors, achieving the optimized tooth surface modification effect. Validation against finite element analysis (FEA) confirms that the proposed method substantially improves optimization efficiency while maintaining accuracy. Results highlight the necessity of load-based optimization.

边缘接触，一个常见的和高度有害的问题，在齿轮传动，显着降低齿轮的性能和使用寿命。点接触面齿轮（FG）对特别容易受到这个问题的影响，因为配合正齿轮比产生齿轮少1-3个齿。针对这一问题，提出了一种基于载荷的FG副迭代修正设计方法。首先，利用修改后的生成齿轮设计修改后的FG，确定初始修改参数，然后确定FG副的潜在接触线。然后，根据负载确定加载接触参数，包括接触模式、负载分配比和时变啮合刚度（TVMS），以评估啮合状态。在此基础上，在闭环设计周期内迭代调整修改参数。最终，导出的修形参数消除了齿缘接触，即使在额定载荷或安装误差为120%的情况下，也能保持稳定的接触模式，从而达到优化的齿面修形效果。对有限元分析（FEA）的验证证实了所提出的方法在保持精度的同时大大提高了优化效率。结果强调了基于负载的优化的必要性。

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引用次数: 0

Construction and mobility analysis of networks of deployable even-sided equilateral polygons 可展开的均匀等边多边形网络的构造与机动性分析

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-01-06 DOI: 10.1016/j.mechmachtheory.2025.106346

Xianwen Kong

Deployable planar mechanisms represent a classical category of deployable systems with broad applications in civil engineering, space exploration, metamaterials, and beyond — either as standalone structures or as compositional units. Despite significant progress in recent decades, designing such mechanisms remains challenging due to their overconstrained nature. This paper addresses the construction and mobility analysis of networks of deployable even-sided equilateral polygons (NDEEPs). Two approaches are proposed: the link-connection method and the joint-connection approach. Three classes of one degree-of-freedom (DOF) NDEEPs and one class of 2-DOF NDEEPs are introduced. Since conventional formulas for the mobility analysis are not applicable to NDEEPs derived via the link-connection method, a mobility analysis method based on a minimal set of constraint equations is proposed. The geometric characteristics of these NDEEPs are also identified. Two classes of NDEEPs derived from tessellations differ fundamentally from hinged tessellations. Additionally, two novel tessellations composed of three types of semi-regular equilateral polygons are discovered as a by-product. This work complements existing research on expanding polygon arrays, hinged tessellations, and deployable networks, contributing to the broader study of overconstrained mechanisms.

可展开平面机构代表了可展开系统的一个经典类别，在土木工程、空间探索、超材料等领域有着广泛的应用——无论是作为独立结构还是作为组成单元。尽管近几十年来取得了重大进展，但由于其过度约束的性质，设计此类机制仍然具有挑战性。本文研究了可展开的均匀等边多边形（NDEEPs）网络的构造和移动性分析。提出了两种方法：链接连接法和联合连接法。介绍了3类单自由度ndeep和1类2自由度ndeep。由于传统的迁移率分析公式不适用于由链接连接法导出的ndeep，提出了一种基于约束方程最小集的迁移率分析方法。本文还识别了这些NDEEPs的几何特征。从镶嵌中衍生的两类ndeep与铰链镶嵌有本质上的不同。此外，还发现了两种由三种半正等边多边形组成的新型镶嵌。这项工作补充了现有的关于扩展多边形阵列、铰链镶嵌和可部署网络的研究，有助于对过度约束机制进行更广泛的研究。

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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 : 2026-04-01 Epub 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

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 : 2026-04-01 Epub 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

Passive gravity compensation in mechanisms and robots: Methods, advances, and challenges 机械和机器人中的被动重力补偿：方法、进展和挑战

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-01-07 DOI: 10.1016/j.mechmachtheory.2025.106345

Vu Linh Nguyen

Passive gravity compensation plays a crucial role in reducing actuator effort, improving energy efficiency, and enhancing ergonomics in mechanisms and robotic systems. This review presents a comprehensive overview of passive gravity compensation, focusing on fundamental methods, recent advances, and emerging challenges. Gravity compensation mechanisms are systematically classified based on the types of structures used to implement energy storage elements. Distinct from prior reviews, this work highlights three major research frontiers in the field: compensation for variable payloads, innovations in multi-degree-of-freedom (multi-DoF) compensation, and the integration of novel energy storage elements. Additionally, the review also provides future research directions and challenges in the field of gravity compensation, including self-regulated gravity compensation for variable payloads, the multi-DoF coupling problem in spatial manipulators, the impact of non-ideal components such as friction and hysteresis, multi-objective design trade-offs, and emerging synergies with artificial intelligence. By bridging theoretical modeling with practical implementation, this review provides a roadmap for developing scalable, adaptive, and deployable gravity-compensated systems for industrial, wearable, and collaborative robotic applications.

在机械和机器人系统中，被动重力补偿在减少作动器的工作量、提高能量效率和增强人体工程学方面起着至关重要的作用。本文综述了被动重力补偿的基本方法、最新进展和面临的挑战。重力补偿机制根据实现储能元件的结构类型进行了系统的分类。与之前的综述不同，本研究突出了该领域的三个主要研究前沿：可变有效载荷补偿、多自由度补偿的创新以及新型储能元件的集成。展望了重力补偿领域未来的研究方向和挑战，包括可变载荷的自调节重力补偿、空间机械臂的多自由度耦合问题、摩擦和滞后等非理想因素的影响、多目标设计权衡以及与人工智能的协同作用。通过将理论建模与实际实现相结合，本综述为工业、可穿戴和协作机器人应用开发可扩展、自适应和可部署的重力补偿系统提供了路线图。

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引用次数: 0

Dynamic modeling and friction parameter identification of a hybrid robot considering active and passive joint frictions 考虑主动和被动关节摩擦的混合动力机器人动力学建模与摩擦参数辨识

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-01-08 DOI: 10.1016/j.mechmachtheory.2025.106348

Yue Ma , Long Chen , Haitao Liu , Bin Li , Qi Liu , Honggui Peng , Dun Peng

The joint frictions will increase the pose error and trajectory deviation of a robot. Taking the TriMule-200 hybrid robot as an example, this paper proposes a dynamic modeling method considering both the active and passive joint frictions, along with a friction parameter identification method based on the Gaussian Quantum Particle Swarm Optimization (GQPSO) algorithm. The former integrates the Newton-Euler method with screw theory to formulate rigid-body dynamic equations for each component, leading to a linear equation system with driving forces/torques and joint constraint forces/moments as variables. A stepwise solution strategy is implemented to compute the driving forces/torques that considering joint frictions modeled by the Stribeck friction model. The latter adopts the global sensitivity analysis method based on variance and covariance decomposition (VCD-GSA) to identify highly sensitive friction parameters, which are then estimated using the GQPSO algorithm by minimizing the mean square error between the predicted and measured driving torques. The experimental results show that the predicted accuracy (R²) of the driving torques exceeds 96.63 % across both the identification and verification trajectories, thereby verifying the effectiveness of the proposed method.

关节摩擦会增加机器人的位姿误差和轨迹偏差。以TriMule-200混合动力机器人为例，提出了一种考虑主动和被动关节摩擦的动态建模方法，以及基于高斯量子粒子群优化（GQPSO）算法的摩擦参数辨识方法。前者将牛顿-欧拉法与螺杆理论相结合，建立各部件的刚体动力学方程，得到以驱动力/扭矩和关节约束力/力矩为变量的线性方程组。考虑Stribeck摩擦模型所建立的关节摩擦，采用分步求解策略计算驱动力/扭矩。后者采用基于方差和协方差分解的全局灵敏度分析方法（VCD-GSA）识别高度敏感的摩擦参数，然后利用GQPSO算法通过最小化预测和实测驱动扭矩之间的均方差来估计高敏感的摩擦参数。实验结果表明，在识别和验证轨迹上，驱动转矩的预测精度R2均超过96.63%，验证了所提方法的有效性。

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引用次数: 0

The geometry of infinitesimal mobility of closed-loop linkages 闭环连杆机构无穷小运动的几何性质

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-01-02 DOI: 10.1016/j.mechmachtheory.2025.106332

Nir Shvalb , Oded Medina

Classical mobility criteria such as the Chebyshev-Grübler-Kutzbach formula capture only first-order behaviour and may overlook geometric constraints of higher order. In this work we examine a large family of spatial closed-loop mechanisms that, despite satisfying the classical mobility count, are found to be rigid. Motivated by unexpectedly elegant geometric structure underlying this behaviour, we introduce the term hypo-paradoxical linkages to describe these mechanisms.

Our analysis combines screw theory with geometric considerations to identify when such higher-order restrictions arise and how they suppress motion. Representative examples are examined, and the effects of small design perturbations on the attainable workspace are quantified.

This geometric viewpoint also offers a fresh and intuitive interpretation of mobility of Bennet’s mechanism.

Overall, the results illustrate the limitations of traditional mobility criteria and point to a richer geometric foundation governing rigidity and motion in spatial linkages.

经典的迁移率标准，如切比舍夫-格拉伯勒-库茨巴赫公式，只捕捉一阶行为，而可能忽略高阶的几何约束。在这项工作中，我们研究了一个大的空间闭环机制家族，尽管满足经典的流动性计数，被发现是刚性的。由于这种行为背后出人意料的优雅几何结构，我们引入了术语“准悖论连杆”来描述这些机制。我们的分析将螺旋理论与几何考虑相结合，以确定何时出现这种高阶限制以及它们如何抑制运动。研究了代表性的例子，并量化了小的设计扰动对可实现的工作空间的影响。这种几何观点也为班纳特机械的机动性提供了一种新鲜而直观的解释。总的来说，结果说明了传统的流动性标准的局限性，并指出了一个更丰富的几何基础来控制空间联系的刚性和运动。

引用次数: 0

Falling dynamics: Accessible saddle and crisis transfer in a passive dynamic Walker 下降动力学：被动动态步行者的可达鞍座和危机转移

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-04-01 Epub Date: 2026-01-03 DOI: 10.1016/j.mechmachtheory.2025.106341

Yumeng Bao , Jianshe Gao , Lei Wan , Qichao Wang , Jianzhuang Zhao , Xiaobo Rao

Falling is a serious consequence of gait disturbances and gait instability in both humans and bipedal walking systems, yet its underlying dynamical mechanisms remain poorly understood. This study systematically identifies and analyzes three distinct falling scenarios in a passive biped robot. The first involves a local bifurcation, in which the period-1 stable gait disappears via a saddle-node bifurcation. The other two are induced by global bifurcations: one triggered by a boundary crisis involving a period-1 saddle, and the other by a more complex double boundary crisis associated with a period-3 saddle. From a global dynamical perspective, these crises are shown to result from transitions between accessible saddle orbits located on the basin boundary—a phenomenon referred to as crisis transfer. To validate these theoretical predictions, a physical robot prototype is developed and tested through both numerical simulations and real-world experiments. The results confirm the predicted gait evolution and fall mechanisms. Overall, these findings offer new insights into the intrinsic dynamics of falling in bipedal systems and provide a theoretical foundation for evaluating and optimizing gait stability and fall prevention strategies.

跌倒是人类和双足行走系统中步态紊乱和步态不稳定的严重后果，但其潜在的动力学机制尚不清楚。本研究系统地识别和分析了被动双足机器人的三种不同的坠落场景。第一种是局部分岔，第一期稳定步态通过鞍节点分岔消失。另外两个是由全局分岔引起的：一个是由涉及时期1鞍的边界危机引发的，另一个是由与时期3鞍相关的更复杂的双边界危机引发的。从全局动力学的角度来看，这些危机是由位于盆地边界的可达鞍轨道之间的过渡造成的，这种现象被称为危机转移。为了验证这些理论预测，开发了一个物理机器人原型，并通过数值模拟和现实世界的实验进行了测试。结果证实了预测的步态进化和跌倒机制。总的来说，这些发现为两足系统跌倒的内在动力学提供了新的见解，并为评估和优化步态稳定性和预防跌倒策略提供了理论基础。

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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 : 2026-04-01 Epub 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