Mechanism and Machine Theory最新文献_第2页

Spectral distribution decomposition and its application in gearbox fault diagnosis 谱分布分解及其在齿轮箱故障诊断中的应用

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-15 DOI: 10.1016/j.mechmachtheory.2026.106359

Decai Li , Guofeng Wang , Mian Zhang , Wei Dai

Existing signal decomposition algorithms suffer from mode mixing, decomposition instability, and poor noise resistance, hindering subsequent feature extraction and fault diagnosis. To address these issues, this paper proposes a spectral distribution decomposition (SDD) algorithm based on the spectral probability density function (SPDF) for gearbox fault diagnosis. The proposed SDD employs a spectral distribution strategy utilizing maximum broadcasting and Gaussian kernel convolution to transform raw spectra into the SPDF, which characterizes signal distribution properties. Integrating the SPDF with the expectation-maximization (EM) algorithm, SDD decomposes signals into multiple distribution mode functions (DMFs) with well-defined frequency boundaries and a residual signal. For gearbox fault diagnosis, an adaptive filtering strategy incorporating SDD is developed to extract fault-related frequency bands and diagnosis indicators. Comparative simulations with well-known decomposition techniques, together with experimental tests on the fault diagnosis of laboratory gearboxes and actual wind turbine gearboxes, demonstrate the effectiveness and superiority of the proposed approach.

现有的信号分解算法存在模式混叠、分解不稳定、抗噪声能力差等问题，影响了后续的特征提取和故障诊断。针对这些问题，本文提出了一种基于谱概率密度函数（SPDF）的齿轮箱故障诊断谱分布分解算法。提出的SDD采用最大广播和高斯核卷积的频谱分布策略，将原始频谱转换为SPDF，表征信号的分布特性。SDD将SPDF与期望最大化（EM）算法相结合，将信号分解为具有明确频率边界和残差信号的多个分布模式函数（dmf）。针对齿轮箱故障诊断，提出了一种结合SDD的自适应滤波策略，提取故障相关频带和诊断指标。将该方法与常用的分解方法进行了仿真对比，并对实验室齿轮箱和实际风电齿轮箱进行了故障诊断实验，验证了该方法的有效性和优越性。

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引用次数: 0

Automated kinetostatic modeling approach for flexure-based mechanisms 基于柔性机构的自动动静力建模方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-14 DOI: 10.1016/j.mechmachtheory.2026.106360

Houqi Wu, Guimin Chen

Modeling the kinetostatics of a flexure-based mechanism is crucial for characterizing its performances and optimizing its parameters. However, the kinetostatic modeling is always a very complicated and error-prone process because it involves formulating not only the loop-closure equations, but also a large number of load equilibrium equations. In this work, we present a general approach that can automatically generate kinetostatic models for planar flexure-based mechanisms. The proposed approach represents the topological structure of a flexure-based mechanism using an incidence matrix and a path matrix, based on which the loop-closure equations and load equilibrium equations are uniformly formulated. These equations are simultaneously solved for the kinetostatic behaviors of the mechanism. All the load equilibrium equations are formulated at vertices instead of links, which eliminates the need of introducing virtual hinges. The automated approach is implemented in an integrated software package with graphical user interface to facilitate the kinetostatic modeling of various flexure-based mechanisms. The effectiveness of the proposed approach is demonstrated by three examples, including a flexure-based displacement amplifier, a microscopic rotation converter, a planar parallel 3-DOF nanopositioner, and a double-output mechanism showing its accuracy and broad applicability.

柔性机构的动静力学建模是表征其性能和优化其参数的关键。然而，动静力学建模是一个非常复杂且容易出错的过程，因为它不仅需要建立闭环方程，还需要建立大量的负载平衡方程。在这项工作中，我们提出了一种通用的方法，可以自动生成平面柔性机构的动静力模型。该方法利用关联矩阵和路径矩阵表示柔度机构的拓扑结构，并在此基础上统一建立了闭环方程和载荷平衡方程。同时求解了机构的动静力行为。所有的载荷平衡方程都是在顶点而不是在连杆上建立的，从而消除了引入虚拟铰链的需要。自动化方法在集成软件包中实现，具有图形用户界面，以方便各种基于柔性的机构的动静态建模。通过柔性位移放大器、微观旋转变换器、平面并联三自由度纳米位移器和双输出机构等实例，验证了该方法的有效性和适用性。

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引用次数: 0

An offline path planning framework for reconfigurable cable-driven parallel mechanisms via Lie algebra interpolation 基于李代数插值的可重构缆索驱动并联机构离线路径规划框架

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-14 DOI: 10.1016/j.mechmachtheory.2025.106349

Zhenkun Liang , Zhengtao Chen , Shujie Tang , Lingyu Kong , Hao Wang , Genliang Chen

The workspace of cable-driven parallel mechanisms (CDPMs) is generally non-convex. To overcome workspace limitations and cable interference, reconfigurable cable-driven parallel mechanisms (RCDPMs) utilize inherent motion redundancy, which, however, introduces additional complexity into the path planning due to more intricate constraints and increased degrees of freedom. This paper proposes an offline path planner capable of identifying feasible paths within a 6-D non-convex workspace, applicable to both CDPMs and RCDPMs. The kinematic, statics and physical constraints relevant to offline path planning are thoroughly described. Special attention is given to an enhanced method developed for detecting inter-cable interference. Bézier interpolations are employed within Lie algebra space to establish the initial path point sequence. An approach for selecting auxiliary control points is introduced, ensuring that the generated paths maintain C² continuity. To ensure path feasibility, a transit point search method operating within the orthogonal subspace of the initial path is proposed, effectively relocating points from outside the workspace into feasible regions. The attachment points reconfiguration is treated as a dimensional synthesis problem, integrated into both discrete feasibility checks and global path optimization. The effectiveness of the proposed path planner is validated through extensive cases, including rotational, translational, and 6-D motions. Furthermore, a simple prototype is constructed to verify the correctness.

缆索驱动并联机构的工作空间通常是非凸的。为了克服工作空间限制和电缆干扰，可重构电缆驱动并联机构（rcdpm）利用固有的运动冗余，然而，由于更复杂的约束和自由度的增加，这给路径规划带来了额外的复杂性。本文提出了一种离线路径规划器，能够在6维非凸工作空间内识别可行路径，适用于cdpm和rcdpm。详细描述了与离线路径规划相关的运动学、静力学和物理约束。特别注意了一种用于检测电缆间干扰的改进方法。在李代数空间内采用bsamizier插值法建立初始路径点序列。介绍了一种选择辅助控制点的方法，以确保生成的路径保持C2连续性。为了保证路径的可行性，提出了在初始路径的正交子空间内进行中转点搜索的方法，有效地将工作空间外的点重新定位到可行区域内。将附着点重构作为一个维度综合问题，集成到离散可行性检验和全局路径优化中。通过广泛的案例验证了所提出的路径规划器的有效性，包括旋转、平移和6-D运动。此外，还构造了一个简单的原型来验证该方法的正确性。

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引用次数: 0

A semi-analytical approach towards determining the largest collision-free sphere in R3 inside the effective regular workspace of a 6-6 Stewart-Gough platform manipulator corresponding to a given orientation workspace 6-6 Stewart-Gough平台机械臂在给定方位工作空间下的有效规则工作空间内R3中最大无碰撞球面的半解析方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-09 DOI: 10.1016/j.mechmachtheory.2025.106331

Bibekananda Patra, Nishanth Adithya Chandramouli, Sandipan Bandyopadhyay

This article focusses on the problem of interference among the links of a parallel robot, namely, the Stewart-Gough platform manipulator. The geometry of the legs is approximated by capsules, leading to the detection of collision among any pair of legs in terms of tangency of the corresponding capsules. Analytical conditions for the said cases of tangency are derived in closed-form, which manifest geometrically as certain quadrics in space. Through a thorough study and explicit characterisation of these surfaces, novel analytical methods are developed to find the largest spheres in space which are tangent to these surfaces. Such spheres are free of possibilities of link collisions, and they can be derived analytically for a given orientation of the moving platform of the manipulator. The analysis is subsequently extended to the orientation workspace of the manipulator by repeating the above-mentioned computations over a large number of discrete samples. The results obtained are verified numerically by comparing them with those generated from other sources. A parametric study is performed to demonstrate the utility of the proposed analysis in practice.

本文主要研究Stewart-Gough平台型并联机器人各环节间的干扰问题。腿的几何形状由胶囊近似，从而根据相应胶囊的切线检测任意一对腿之间的碰撞。这些切线的解析条件以封闭形式导出，在几何上表现为空间上的某些二次曲线。通过对这些表面的深入研究和明确表征，开发了新的分析方法来寻找与这些表面相切的空间中最大的球体。这种球体不存在连杆碰撞的可能性，并且可以在给定的机械手运动平台方向下解析导出。通过在大量离散样本上重复上述计算，将分析扩展到机械臂的定向工作空间。将所得结果与其他来源的结果进行了数值验证。进行了参数化研究，以证明所提出的分析在实践中的效用。

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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 : 2026-01-08 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

Analysis and control of a variable inerter-based vibration mitigation system 基于变干涉的减振系统分析与控制

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-08 DOI: 10.1016/j.mechmachtheory.2025.106344

Peter Pacsonyi , Csaba Budai , Gabor Stepan

Vibration isolation is one of the most important aspects of mechanical engineering, and various methods are available for protecting vibration-sensitive equipment. This paper focuses on vibration isolation using antiresonance effects provided by inerters. It is concluded that the spring strut complemented with an inerter can substitute the tuned mass damper, thus reducing the number of auxiliary elements and the additional mass of the vibration isolating system. If the inertance is variable, it can modify the frequency response of the system. With an appropriate nonlinear control strategy, it is achievable to tune the frequency of the antiresonance to the dominant frequency of the external excitation, thus reducing the vibration amplitudes. This paper presents the modeling and analysis of the variable inerter as well as developing a feedback linearization-based control algorithm.

隔振是机械工程中最重要的一个方面，保护振动敏感设备的方法多种多样。本文的重点是利用隔振器提供的抗共振效应进行隔振。结果表明，弹簧杆配以干涉器可以代替调谐质量阻尼器，从而减少了辅助元件的数量和隔振系统的附加质量。如果惯量是可变的，它可以改变系统的频率响应。通过适当的非线性控制策略，可以将反共振的频率调谐到外部激励的主频率，从而减小振动幅值。本文介绍了可变干扰器的建模和分析，并开发了一种基于反馈线性化的控制算法。

引用次数: 0

A novel model of lubricated contact for spur gears 一种新的正齿轮润滑接触模型

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-07 DOI: 10.1016/j.mechmachtheory.2025.106334

Laís Carrer , Laís Bittencourt Visnadi , Natalia Akemi Hoshikawa Tsuha , Katia Lucchesi Cavalca , Helio Fiori De Castro

Research on gear dynamics is vital for power transmission. While elastohydrodynamic lubrication (EHL) significantly affects gear behavior, its computational cost is high. This study presents a reduced EHL model for gear teeth line contact, derived from numerical results for various Moes parameters. Parameters like stiffness, damping, and oil film thickness are adimensionalized, forming a grid map linking load, displacement, and film thickness under specific conditions. By solving the EHL model for each parameter combination, the approach is computationally efficient. The lubricated contact model is integrated into a lumped parameter gear pair model, with frequency domain displacement validated against experiments. Results reveal torque increases amplify displacement peaks, while speed changes have minimal effect when torque remains constant.

齿轮动力学研究对动力传动具有重要意义。弹流润滑对齿轮性能影响较大，但计算成本较高。根据不同Moes参数的数值结果，提出了齿轮齿线接触的简化EHL模型。将刚度、阻尼、油膜厚度等参数量纲化，在特定条件下形成连接载荷、位移和油膜厚度的网格图。通过求解各参数组合的EHL模型，提高了算法的计算效率。将润滑接触模型集成到集总参数齿轮副模型中，并通过频域位移与实验验证。结果表明，扭矩增大会放大位移峰值，而当扭矩保持不变时，速度变化对位移峰值的影响最小。

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 : 2026-01-07 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

Non-inertial multi-DOF dynamic modeling and experimental analysis of marine gear systems subjected to wave-induced motions 船舶齿轮系统受波浪运动影响的非惯性多自由度动力学建模与实验分析

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2026-01-06 DOI: 10.1016/j.mechmachtheory.2025.106343

Yiwei Hu , Zheming Tong , Xianmiao Yang , Shuiguang Tong , Huadong Ying , Peicheng Zhang

Marine gear transmission systems are subjected to complex dynamic excitations from wave-induced motions. These non-inertial effects lead to nonlinear system behavior and an increased risk of resonance. This study presents a non-inertial multiple degree-of-freedom (DOF) dynamic model for marine gear systems, which incorporates inertial and gyroscopic effects through reference frame transformations and kinematic decomposition. To validate the model, a 6-DOF vibration test platform is developed to simulate periodic platform motions. Experiments under fixed, heaving, and rolling conditions confirm the accuracy of the dynamic model. The results reveal that platform heaving motion primarily excites the lateral bending mode through meshing stiffness modulation, increasing lateral bending vibration by up to 6.06 %, and intensifying meshing impacts. In contrast, rolling motion injects energy into the torsional mode via inertia‑induced phase modulation, producing a 48.23 % amplification of torsional response and a 32.5 % stronger modulation effect than heaving. Time‑frequency results indicate that rolling leads to intensified nonlinear modulation coupling with higher spectral energy and frequency drift. The quantified analysis provides design guidance for optimizing structural stiffness and damping of marine gear systems operating under non‑inertial platform motions.

船舶齿轮传动系统受到波浪运动的复杂动力激励。这些非惯性效应导致系统的非线性行为和共振的风险增加。通过参照系变换和运动学分解，建立了船舶齿轮系统的非惯性多自由度动力学模型，该模型综合了惯性效应和陀螺效应。为了验证该模型，开发了一个六自由度振动测试平台来模拟平台的周期性运动。在固定、起伏和滚动条件下的实验证实了动态模型的准确性。结果表明，平台升沉运动主要通过啮合刚度调制激发横向弯曲模式，使横向弯曲振动增加6.06%，并加剧了啮合冲击。相比之下，滚动运动通过惯性诱导的相位调制向扭转模式注入能量，使扭转响应放大48.23%，调制效果比起伏强32.5%。时频结果表明，滚动导致非线性调制耦合加剧，频谱能量和频率漂移增大。量化分析为在非惯性平台运动下运行的船用齿轮系统的结构刚度和阻尼优化提供了设计指导。

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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 : 2026-01-06 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