Mechanism and Machine Theory最新文献_第9页

Multi-fidelity harmonic balance method: A non-intrusive approach 多保真谐波平衡法：一种非干扰的方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-08 DOI: 10.1016/j.mechmachtheory.2025.106251

Hady Mohamed , Nils Brödling , Fabian Duddeck

This paper presents a novel non-intrusive hierarchical multi-fidelity harmonic balance method (HBM) framework for efficient uncertainty quantification (UQ) of nonlinear frequency response functions (FRFs) with application to gear transmission dynamics. The framework uniquely combines proper orthogonal decomposition (POD) to reduce the dimensionality of HBM-derived Fourier coefficients, enable efficient surrogate modeling in latent space, and retain access to both time- and frequency-domain responses. A key innovation is aligning low- and high-fidelity Fourier coefficient latent spaces via Procrustes analysis to improve the construction of a multi-fidelity surrogate using hierarchical Kriging with polynomial chaos Kriging (PCK) as the trend function. Further, computational efficiency in low-fidelity evaluations is achieved by integrating POD with linear regression for rapid compliance matrix estimation in loaded tooth contact analysis (LTCA). Numerical results demonstrate significant computational savings for uncertain FRF predictions of 5000 Monte Carlo (MC) samples. The proposed novelties represent the first application of hierarchical Kriging across aligned Fourier latent spaces and accelerated LTCA within a scalable framework for moderate-dimensional, vector-valued FRF uncertainty analysis, supporting broad applicability to nonlinear dynamical systems modeled with Frequency domain solvers.

提出了一种新的非侵入式分层多保真谐波平衡法框架，用于非线性频响函数的不确定性量化，并将其应用于齿轮传动动力学。该框架独特地结合了适当的正交分解（POD），以降低hbm衍生的傅立叶系数的维数，在潜在空间中实现有效的代理建模，并保留对时域和频域响应的访问。一个关键的创新是通过Procrustes分析将低保真和高保真傅里叶系数潜在空间对齐，以多项式混沌克里格（PCK）作为趋势函数，使用分层克里格来改进多保真代理的构建。此外，通过将POD与线性回归相结合，在加载齿接触分析（LTCA）中快速估计柔度矩阵，提高了低保真度评估的计算效率。数值结果表明，对于5000个蒙特卡罗（MC）样本的不确定频响预测，可以显著节省计算量。提出的新方法代表了分层克里格在排列傅立叶潜在空间中的首次应用，并在中等维度、向量值FRF不确定性分析的可扩展框架内加速LTCA，支持广泛适用于用频域求解器建模的非线性动力系统。

{"title":"Multi-fidelity harmonic balance method: A non-intrusive approach","authors":"Hady Mohamed , Nils Brödling , Fabian Duddeck","doi":"10.1016/j.mechmachtheory.2025.106251","DOIUrl":"10.1016/j.mechmachtheory.2025.106251","url":null,"abstract":"<div><div>This paper presents a novel non-intrusive hierarchical multi-fidelity harmonic balance method (HBM) framework for efficient uncertainty quantification (UQ) of nonlinear frequency response functions (FRFs) with application to gear transmission dynamics. The framework uniquely combines proper orthogonal decomposition (POD) to reduce the dimensionality of HBM-derived Fourier coefficients, enable efficient surrogate modeling in latent space, and retain access to both time- and frequency-domain responses. A key innovation is aligning low- and high-fidelity Fourier coefficient latent spaces via Procrustes analysis to improve the construction of a multi-fidelity surrogate using hierarchical Kriging with polynomial chaos Kriging (PCK) as the trend function. Further, computational efficiency in low-fidelity evaluations is achieved by integrating POD with linear regression for rapid compliance matrix estimation in loaded tooth contact analysis (LTCA). Numerical results demonstrate significant computational savings for uncertain FRF predictions of 5000 Monte Carlo (MC) samples. The proposed novelties represent the first application of hierarchical Kriging across aligned Fourier latent spaces and accelerated LTCA within a scalable framework for moderate-dimensional, vector-valued FRF uncertainty analysis, supporting broad applicability to nonlinear dynamical systems modeled with Frequency domain solvers.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106251"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic characteristics of rigid-flexible coupled planetary gear-bearing-rotor system considering the tooth surface lubrication friction and roughness 考虑齿面润滑摩擦和粗糙度的刚柔耦合行星齿轮-轴承-转子系统动态特性

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-15 DOI: 10.1016/j.mechmachtheory.2025.106259

Ning Liu , Hui Ma , Xiangfu Ding , Jiaqi Liu

A novel rigid-flexible coupled planetary gear-bearing-rotor (PBR) dynamic model with bearing-gear coupling effect, modulation of the planetary carrier, roughness, and friction under different lubrication states is established. The necessity of the bearing nonlinear force, the flexible ring and the modulation of the planet carrier in the model is verified through experiments. The improved friction coefficient and the meshing stiffness with lubrication friction are proposed based on elastohydrodynamic lubrication (EHL) and the three-dimensional loaded tooth contact analysis (3D-LTCA) method. The influence of friction under different lubrication conditions on the dynamic characteristics of the PBR system is analyzed. Some interesting phenomena are as follows: friction coefficient of the mixed EHL is greater than that of the EHL at the pitch point. Compared with friction introduced into the stiffness model, the friction introduced into kinematic equations has a greater impact on the PBR system. The low-frequency energy ratio is more sensitive to friction. Meanwhile, compared with the model without friction, friction leads to an increase in the contact force, contact stiffness and contact area of the ball-race, and the dynamic meshing force (DMF).

建立了考虑轴承-齿轮耦合效应、行星载子调制、粗糙度和不同润滑状态下摩擦的刚柔耦合行星齿轮-轴承-转子（PBR）动力学模型。通过实验验证了模型中轴承非线性力、柔性环和行星载体调制的必要性。基于弹流动力润滑（EHL）和三维加载齿接触分析（3D-LTCA）方法，提出了润滑摩擦下改进的摩擦系数和啮合刚度。分析了不同润滑条件下摩擦对PBR系统动态特性的影响。一些有趣的现象如下：在俯角处，混合EHL的摩擦系数大于EHL的摩擦系数。与刚度模型中引入的摩擦力相比，运动学方程中引入的摩擦力对PBR系统的影响更大。低频能量比对摩擦更敏感。同时，与无摩擦模型相比，摩擦导致球滚道的接触力、接触刚度和接触面积增大，动态啮合力（DMF）增大。

{"title":"Dynamic characteristics of rigid-flexible coupled planetary gear-bearing-rotor system considering the tooth surface lubrication friction and roughness","authors":"Ning Liu , Hui Ma , Xiangfu Ding , Jiaqi Liu","doi":"10.1016/j.mechmachtheory.2025.106259","DOIUrl":"10.1016/j.mechmachtheory.2025.106259","url":null,"abstract":"<div><div>A novel rigid-flexible coupled planetary gear-bearing-rotor (PBR) dynamic model with bearing-gear coupling effect, modulation of the planetary carrier, roughness, and friction under different lubrication states is established. The necessity of the bearing nonlinear force, the flexible ring and the modulation of the planet carrier in the model is verified through experiments. The improved friction coefficient and the meshing stiffness with lubrication friction are proposed based on elastohydrodynamic lubrication (EHL) and the three-dimensional loaded tooth contact analysis (3D-LTCA) method. The influence of friction under different lubrication conditions on the dynamic characteristics of the PBR system is analyzed. Some interesting phenomena are as follows: friction coefficient of the mixed EHL is greater than that of the EHL at the pitch point. Compared with friction introduced into the stiffness model, the friction introduced into kinematic equations has a greater impact on the PBR system. The low-frequency energy ratio is more sensitive to friction. Meanwhile, compared with the model without friction, friction leads to an increase in the contact force, contact stiffness and contact area of the ball-race, and the dynamic meshing force (DMF).</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106259"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A new mathematical model for the product family design of the skiving tools of spur face gears 为正齿面齿轮刨削刀具的产品族设计建立了新的数学模型

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-03 DOI: 10.1016/j.mechmachtheory.2025.106232

Zhongwei Tang , Yuansheng Zhou , Shuai Mo , Jinyuan Tang , Zichang Du , Wuji Zhang , Haiyu He

Power skiving is increasingly used in face gear manufacturing while the existing tools are limited to the face gears with specific parameters (module, pressure angle, and tooth number), which reduces flexibility and increases costs. This paper proposes a product family design method for skiving tools aimed at spur face gears. First, a mathematical model of the tooth surface is established, along with an error evaluation framework. Then, an error compensation method is introduced for a specific gear design, and errors are analyzed when using a dedicated tool to machine the face gears with different parameters. Results show that variations in tooth number cause minor errors, while differences in module and pressure angle lead to significant inaccuracies. A product family design approach is proposed to enable one tool to machine multiple gears accurately. Validated through simulations and experiments, the method achieves high precision for gear families with small variations in module and pressure angle. This work offers practical value and theoretical support for developing skiving tool libraries.

动力刨削越来越多地应用于面齿轮制造，而现有的刀具仅限于具有特定参数（模块、压力角和齿数）的面齿轮，这降低了灵活性并增加了成本。提出了一种针对正齿面齿轮的刨削刀具产品族设计方法。首先，建立了齿面数学模型，并建立了误差评估框架。然后，针对具体的齿轮设计，提出了一种误差补偿方法，并分析了使用专用刀具加工不同参数面齿轮时的误差。结果表明，齿数的变化导致的误差较小，而模组和压力角的差异导致的误差较大。提出了一种产品族设计方法，使一个刀具能够精确加工多个齿轮。通过仿真和实验验证，该方法对模数和压力角变化较小的齿轮族具有较高的精度。本文的工作为开发滑行工具库提供了实用价值和理论支持。

{"title":"A new mathematical model for the product family design of the skiving tools of spur face gears","authors":"Zhongwei Tang , Yuansheng Zhou , Shuai Mo , Jinyuan Tang , Zichang Du , Wuji Zhang , Haiyu He","doi":"10.1016/j.mechmachtheory.2025.106232","DOIUrl":"10.1016/j.mechmachtheory.2025.106232","url":null,"abstract":"<div><div>Power skiving is increasingly used in face gear manufacturing while the existing tools are limited to the face gears with specific parameters (module, pressure angle, and tooth number), which reduces flexibility and increases costs. This paper proposes a product family design method for skiving tools aimed at spur face gears. First, a mathematical model of the tooth surface is established, along with an error evaluation framework. Then, an error compensation method is introduced for a specific gear design, and errors are analyzed when using a dedicated tool to machine the face gears with different parameters. Results show that variations in tooth number cause minor errors, while differences in module and pressure angle lead to significant inaccuracies. A product family design approach is proposed to enable one tool to machine multiple gears accurately. Validated through simulations and experiments, the method achieves high precision for gear families with small variations in module and pressure angle. This work offers practical value and theoretical support for developing skiving tool libraries.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106232"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145223549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Is the root fillet curve in involute gears trochoidal? A geometric reassessment 渐开线齿轮的根圆角曲线是摆线的吗？几何重新评估

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-03 DOI: 10.1016/j.mechmachtheory.2025.106228

Alessio Artoni

The root fillet of involute gears is commonly described as “trochoidal”, yet, to the author’s knowledge, the geometric basis for this label has never been stated explicitly. This article addresses the question from geometric first principles. Trochoids are roulettes of points attached to a circle rolling on a base curve, with two subfamilies: line-based (cycloids) and circle-based (epi-/hypotrochoids). Focusing on spur gears and working in a blank-fixed transverse plane, we derive the locus of a generic rack point: the rack tip (or the center of its rounding) traces a prolate involute of a circle, not a trochoid; explicit parametric equations are provided. By contrast, with pinion-shaped cutters the cutter tip (or the center of its rounding) traces a hypotrochoid for internal gears or an epitrochoid for external gears, and thus the nominal fillet is genuinely trochoidal. The same reasoning carries over to helical gears. These findings support clearer and more precise terminology in technical publications and standards.

渐开线齿轮的根圆角通常被描述为“小摆线”，然而，以作者的知识，这个标签的几何基础从未明确表示过。本文从几何第一性原理着手解决这个问题。菱形是附著在基本曲线上滚动的圆上的点的轮盘，有两个亚族：基于线的（摆线）和基于圆的（上/下菱形）。以正齿轮为研究对象，在固定毛坯的横向平面上工作，推导出一般齿条点的轨迹：齿条尖端（或其圆心）沿着一个圆的渐开线延伸，而不是一个齿面；给出了显式参数方程。相比之下，与小齿轮形刀具刀具尖端（或其圆弧的中心）跟踪内齿轮的下齿面或外齿轮的外齿面，因此标称圆角是真正的齿面。同样的道理也适用于螺旋齿轮。这些发现支持在技术出版物和标准中使用更清晰和更精确的术语。

引用次数: 0

A Self-Locking Tendon-Driven Robotic Arm Inspired by Cubic Origami 受立方折纸启发的自锁肌腱驱动机械臂

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-01 DOI: 10.1016/j.mechmachtheory.2025.106230

Fengrui Liu, Tatsuro Terakawa, Zhongzheng Liang, Masaharu Komori

The ability to transition between load-carrying and readily foldable states enables deployable structures to satisfy diverse functional requirements, such as compact storage, adaptive shape transformation, and stable load-bearing performance. Self-locking origami structures, which utilize geometric constraints to prevent the structure from collapsing under external loads, offer an effective solution for achieving these capabilities. In this study, we investigate the self-locking behavior of a Foldable Cube Origami (FC-ori) structure in its cubic configuration by analyzing its geometry and singularity. To address self-locking constraints, a tendon-driven mechanism is developed with tendons routed through the side panels, in contrast to conventional designs where tendons pass only through the top and bottom panels. By optimizing the tendon path, we reduced the maximum friction by approximately 20%. Moreover, we design and implement two multi-unit tendon-driven FC-ori robotic arms configured in series and parallel arrangements. These systems allow for programmable deployment sequences and achieve rapid transitions between folded and deployed configurations within several seconds, driven by only a single motor. By integrating a tunable stiffness origami structure with efficient actuation, this work offers enhanced potential for applications in space exploration, foldable shelters, reconfigurable robotics, and other engineering domains.

在承载状态和易折叠状态之间转换的能力使可展开结构能够满足各种功能需求，例如紧凑存储，自适应形状转换和稳定的承载性能。自锁折纸结构利用几何约束来防止结构在外部负载下坍塌，为实现这些功能提供了有效的解决方案。在本研究中，我们通过分析可折叠立方体折纸（FC-ori）结构的几何形状和奇异性，研究了其在立方构型下的自锁行为。为了解决自锁约束问题，该公司开发了一种肌腱驱动机制，将肌腱穿过侧板，而传统的设计中，肌腱只穿过顶部和底部板。通过优化肌腱路径，我们减少了大约20%的最大摩擦。此外，我们设计并实现了两个多单元串联和并联配置的肌腱驱动FC-ori机械臂。这些系统允许可编程的展开序列，并在几秒钟内实现折叠和展开配置之间的快速转换，仅由单个电机驱动。通过将可调刚度折纸结构与高效驱动相结合，这项工作为空间探索、可折叠庇护所、可重构机器人和其他工程领域的应用提供了更大的潜力。

{"title":"A Self-Locking Tendon-Driven Robotic Arm Inspired by Cubic Origami","authors":"Fengrui Liu, Tatsuro Terakawa, Zhongzheng Liang, Masaharu Komori","doi":"10.1016/j.mechmachtheory.2025.106230","DOIUrl":"10.1016/j.mechmachtheory.2025.106230","url":null,"abstract":"<div><div>The ability to transition between load-carrying and readily foldable states enables deployable structures to satisfy diverse functional requirements, such as compact storage, adaptive shape transformation, and stable load-bearing performance. Self-locking origami structures, which utilize geometric constraints to prevent the structure from collapsing under external loads, offer an effective solution for achieving these capabilities. In this study, we investigate the self-locking behavior of a Foldable Cube Origami (FC-ori) structure in its cubic configuration by analyzing its geometry and singularity. To address self-locking constraints, a tendon-driven mechanism is developed with tendons routed through the side panels, in contrast to conventional designs where tendons pass only through the top and bottom panels. By optimizing the tendon path, we reduced the maximum friction by approximately 20%. Moreover, we design and implement two multi-unit tendon-driven FC-ori robotic arms configured in series and parallel arrangements. These systems allow for programmable deployment sequences and achieve rapid transitions between folded and deployed configurations within several seconds, driven by only a single motor. By integrating a tunable stiffness origami structure with efficient actuation, this work offers enhanced potential for applications in space exploration, foldable shelters, reconfigurable robotics, and other engineering domains.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106230"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145189711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A matrix-based configuration synthesis and design of power-split hybrid transmissions for multi-vehicle application scenarios 基于矩阵的多车动力分流混合动力变速器构型综合与设计

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-25 DOI: 10.1016/j.mechmachtheory.2025.106269

Bihai Deng , Huafeng Ding , Tao Ke , Bin Zi , Andrés Kecskeméthy

This paper presents a matrix-based synthesis and design framework for power-split hybrid transmissions targeting light-duty (L-HEV), medium-duty (M-HEV), and heavy-duty (HHEV) hybrid electric vehicles. A unified structural and position matrix is developed to model planetary gear mechanisms and auxiliary components. This matrix enables automated calculation of rotational speeds and torques, as well as identification of power-split operating modes. Based on this representation, an efficient enumeration algorithm is proposed to generate all feasible configurations, followed by initial screening using kinematic and control feasibility criteria. To evaluate configuration complexity, a composite index is formulated by combining planetary gear structure and shift element layout complexity. Configurations with the lowest complexity are selected and assessed using dynamic programming to analyze acceleration performance and fuel economy across standard driving cycles. The study ultimately identifies eight high-performance configurations for both l-HEV and M-HEV, and 47 preferred configurations for HHEV, each achieving a balance between mechanical simplicity, dynamic performance, and fuel efficiency. The proposed end-to-end framework offers a systematic and practical approach for hybrid transmission design suited to various application scenarios.

针对轻型（L-HEV）、中型（M-HEV）和重型（HHEV）混合动力汽车，提出了一种基于矩阵的动力分流混合动力变速器综合设计框架。建立了行星齿轮机构及其辅助部件的统一结构和位置矩阵。该矩阵能够自动计算转速和扭矩，以及识别功率分割操作模式。在此基础上，提出了一种高效的枚举算法，生成所有可行构型，然后根据运动学和控制可行性准则进行初始筛选。为评价构型复杂度，将行星齿轮结构和换挡元件布局复杂度结合起来，建立了构型复杂度综合指标。选择复杂性最低的配置，并使用动态规划对其进行评估，以分析标准驾驶周期内的加速性能和燃油经济性。该研究最终确定了l-HEV和M-HEV的8种高性能配置，以及HHEV的47种优选配置，每种配置都能在机械简单性、动态性能和燃油效率之间取得平衡。提出的端到端框架为适合各种应用场景的混合动力变速器设计提供了一种系统实用的方法。

{"title":"A matrix-based configuration synthesis and design of power-split hybrid transmissions for multi-vehicle application scenarios","authors":"Bihai Deng , Huafeng Ding , Tao Ke , Bin Zi , Andrés Kecskeméthy","doi":"10.1016/j.mechmachtheory.2025.106269","DOIUrl":"10.1016/j.mechmachtheory.2025.106269","url":null,"abstract":"<div><div>This paper presents a matrix-based synthesis and design framework for power-split hybrid transmissions targeting light-duty (L-HEV), medium-duty (M-HEV), and heavy-duty (H<img>HEV) hybrid electric vehicles. A unified structural and position matrix is developed to model planetary gear mechanisms and auxiliary components. This matrix enables automated calculation of rotational speeds and torques, as well as identification of power-split operating modes. Based on this representation, an efficient enumeration algorithm is proposed to generate all feasible configurations, followed by initial screening using kinematic and control feasibility criteria. To evaluate configuration complexity, a composite index is formulated by combining planetary gear structure and shift element layout complexity. Configurations with the lowest complexity are selected and assessed using dynamic programming to analyze acceleration performance and fuel economy across standard driving cycles. The study ultimately identifies eight high-performance configurations for both <span>l</span>-HEV and M-HEV, and 47 preferred configurations for H<img>HEV, each achieving a balance between mechanical simplicity, dynamic performance, and fuel efficiency. The proposed end-to-end framework offers a systematic and practical approach for hybrid transmission design suited to various application scenarios.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106269"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modelling gear mesh stiffness including axial effects: Approximate approach 齿轮啮合刚度建模包括轴向效应：近似方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-22 DOI: 10.1016/j.mechmachtheory.2025.106221

Francisco H.J. Ricardo , João D.M. Marafona , Pedro M.T. Marques

Recently, with the advancement in technology, gear mesh stiffness has been a central topic in gear design optimisation and gear dynamics. Consequently, some approximate models for spur and helical gears have been developed due to their low computational cost. However, these models disregarded the axial component of the gear mesh stiffness. To address this issue, a new approximate expression is developed accounting for the axial effect, having as starting point a previously developed approximate expression that considers only the transverse component. The new expression is validated for a random sample representative of all possible gears within a wide range of geometric parameters. The new approximate model for helical gears, based on the development of an expression for the single tooth pair slice structural mesh stiffness, revealed to be fast and accurate, confirming the applicability of the model and proving that it is capable of replacing the more time consuming methods for the same applications. Additionally, a single equation relying on a single constant aiming to convert the transverse into normal stiffness is presented.

近年来，随着技术的进步，齿轮啮合刚度已成为齿轮设计优化和齿轮动力学的中心课题。因此，由于正齿轮和斜齿轮的计算成本较低，人们开发了一些近似模型。然而，这些模型忽略了齿轮啮合刚度的轴向分量。为了解决这个问题，开发了一个新的近似表达式，考虑轴向效应，以先前开发的近似表达式为起点，只考虑横向分量。新的表达式验证了一个随机样本代表所有可能的齿轮在广泛的几何参数范围内。在建立单齿对片结构啮合刚度表达式的基础上，建立的斜齿轮近似模型快速、准确，验证了该模型的适用性，并证明了该模型能够代替耗时较长的方法实现相同的应用。此外，还提出了一个依赖于单一常数的单一方程，旨在将横向刚度转换为法向刚度。

{"title":"Modelling gear mesh stiffness including axial effects: Approximate approach","authors":"Francisco H.J. Ricardo , João D.M. Marafona , Pedro M.T. Marques","doi":"10.1016/j.mechmachtheory.2025.106221","DOIUrl":"10.1016/j.mechmachtheory.2025.106221","url":null,"abstract":"<div><div>Recently, with the advancement in technology, gear mesh stiffness has been a central topic in gear design optimisation and gear dynamics. Consequently, some approximate models for spur and helical gears have been developed due to their low computational cost. However, these models disregarded the axial component of the gear mesh stiffness. To address this issue, a new approximate expression is developed accounting for the axial effect, having as starting point a previously developed approximate expression that considers only the transverse component. The new expression is validated for a random sample representative of all possible gears within a wide range of geometric parameters. The new approximate model for helical gears, based on the development of an expression for the single tooth pair slice structural mesh stiffness, revealed to be fast and accurate, confirming the applicability of the model and proving that it is capable of replacing the more time consuming methods for the same applications. Additionally, a single equation relying on a single constant aiming to convert the transverse into normal stiffness is presented.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106221"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Configuration design and redundancy optimization of a novel kinematically redundant parallel external fixator for interference avoidance in foot and ankle deformity correction 一种新型运动冗余并联外固定架的结构设计与冗余优化，用于足、踝畸形矫治中避免干扰

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-18 DOI: 10.1016/j.mechmachtheory.2025.106265

Jie Ju , Jianfeng Li , Tuxian Ye , Qianhui Ma , Mingjie Dong , Shiping Zuo , Wei-Hsin Liao

During foot and ankle deformity correction via external fixators, successful implementation of the preplanned optimal correction strategy is crucial for achieving acceptable correction outcomes. However, interference phenomena can interrupt the correction process. Owing to the inherent non-redundant mechanism properties of existing external fixators, current interference avoidance methods inevitably necessitate adjustments of the pre-determined assembly relation and/or equally-spaced correction trajectories, thereby hindering the implementability of the optimal correction strategy. To address this issue, this paper introduces the concept of kinematic redundancy in external fixator design, and a novel 2(SPS-P-SPS)-SPR kinematically redundant external fixator with configuration optimization capabilities is proposed. Subsequently, based on the algebraic solution for forward kinematics while combining the cost functions for interference avoidance tasks, the inverse kinematics of the proposed external fixator is resolved using the gradient projection method with closed-loop feedback. Clinical case simulations demonstrate the effectiveness of the external fixator in avoiding multiple interference problems while maintaining the optimal correction strategy. Comparative analyses further reveal considerable improvements in the tracking accuracy of the correction trajectory compared with the conventional velocity-level method with open-loop solutions.

在通过外固定架进行足部和踝关节畸形矫正时，成功实施预先规划的最佳矫正策略对于获得可接受的矫正结果至关重要。然而，干扰现象会中断校正过程。由于现有外固定器固有的非冗余机构特性，当前的干涉避免方法不可避免地需要调整预先确定的装配关系和/或等间距校正轨迹，从而阻碍了最优校正策略的实现。为了解决这一问题，本文在外固定架设计中引入了运动冗余的概念，提出了一种具有构型优化能力的2(SPS-P-SPS)-SPR运动冗余外固定架。随后，在求解正运动学代数解的基础上，结合避免干扰任务的代价函数，采用带闭环反馈的梯度投影法求解该外固定器的运动学逆解。临床案例模拟证明了外固定架在避免多重干扰问题的同时保持最佳矫正策略的有效性。对比分析进一步表明，与传统的开环速度级方法相比，修正轨迹的跟踪精度有了很大提高。

{"title":"Configuration design and redundancy optimization of a novel kinematically redundant parallel external fixator for interference avoidance in foot and ankle deformity correction","authors":"Jie Ju , Jianfeng Li , Tuxian Ye , Qianhui Ma , Mingjie Dong , Shiping Zuo , Wei-Hsin Liao","doi":"10.1016/j.mechmachtheory.2025.106265","DOIUrl":"10.1016/j.mechmachtheory.2025.106265","url":null,"abstract":"<div><div>During foot and ankle deformity correction via external fixators, successful implementation of the preplanned optimal correction strategy is crucial for achieving acceptable correction outcomes. However, interference phenomena can interrupt the correction process. Owing to the inherent non-redundant mechanism properties of existing external fixators, current interference avoidance methods inevitably necessitate adjustments of the pre-determined assembly relation and/or equally-spaced correction trajectories, thereby hindering the implementability of the optimal correction strategy. To address this issue, this paper introduces the concept of kinematic redundancy in external fixator design, and a novel 2(S<u>P</u>S-<u>P</u>-S<u>P</u>S)-S<u>P</u>R kinematically redundant external fixator with configuration optimization capabilities is proposed. Subsequently, based on the algebraic solution for forward kinematics while combining the cost functions for interference avoidance tasks, the inverse kinematics of the proposed external fixator is resolved using the gradient projection method with closed-loop feedback. Clinical case simulations demonstrate the effectiveness of the external fixator in avoiding multiple interference problems while maintaining the optimal correction strategy. Comparative analyses further reveal considerable improvements in the tracking accuracy of the correction trajectory compared with the conventional velocity-level method with open-loop solutions.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106265"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145325468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermo-cavitation study of helical gears caused by vibration 螺旋齿轮振动引起的热空化研究

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-06 DOI: 10.1016/j.mechmachtheory.2025.106239

Tiancheng Ouyang , Yinxuan Li , Hongyang Tian , Shaohui Qin , Yang Yang , Yong Chen

In the context of high-precision manufacturing, filling the gap in the study of the correlation between helical gear dynamics and thermo-cavitation has a significant impact on the optimal design of transmission systems. For this purpose, a cavitation two-phase flow research system containing fluid energy, temperature and dynamic model is constructed, aiming at studying the phenomenon of vibration-cavitation under the non-constant flow and variable temperature of oil in helical gear system, analyzing the evolution law of cavitation in the meshing region and revealing the thermo-cavitation generation mechanism under the influence of vibration. Besides, the reliability of the numerical method is assessed by the relative error between the experimental and simulation results. The results show that fluid thermal effect has a significant impact on cavitation at extreme operating conditions, with high speeds being the main factor in the dramatic increase in cavitation. The load profoundly affects the fluctuation of cavitation and the contact surface temperature, but there exists an optimal value to achieve a balance between the two, the value of helix angle between 15° and 20° is a well choice.

在高精度制造的背景下，填补斜齿轮动力学与热空化关系研究的空白对传动系统的优化设计具有重要意义。为此，构建了一个包含流体能量、温度和动力学模型的空化两相流研究系统，旨在研究斜齿轮系统中油液非定流变温条件下的振动空化现象，分析啮合区域空化的演化规律，揭示振动影响下的热空化产生机理。并通过实验结果与仿真结果的相对误差来评价数值方法的可靠性。结果表明，在极端工况下，流体热效应对空化有显著影响，高速是导致空化急剧增加的主要因素。载荷对空化和接触面温度的波动影响较大，但两者之间存在一个最优值，螺旋角在15°和20°之间是一个较好的选择。

{"title":"Thermo-cavitation study of helical gears caused by vibration","authors":"Tiancheng Ouyang , Yinxuan Li , Hongyang Tian , Shaohui Qin , Yang Yang , Yong Chen","doi":"10.1016/j.mechmachtheory.2025.106239","DOIUrl":"10.1016/j.mechmachtheory.2025.106239","url":null,"abstract":"<div><div>In the context of high-precision manufacturing, filling the gap in the study of the correlation between helical gear dynamics and thermo-cavitation has a significant impact on the optimal design of transmission systems. For this purpose, a cavitation two-phase flow research system containing fluid energy, temperature and dynamic model is constructed, aiming at studying the phenomenon of vibration-cavitation under the non-constant flow and variable temperature of oil in helical gear system, analyzing the evolution law of cavitation in the meshing region and revealing the thermo-cavitation generation mechanism under the influence of vibration. Besides, the reliability of the numerical method is assessed by the relative error between the experimental and simulation results. The results show that fluid thermal effect has a significant impact on cavitation at extreme operating conditions, with high speeds being the main factor in the dramatic increase in cavitation. The load profoundly affects the fluctuation of cavitation and the contact surface temperature, but there exists an optimal value to achieve a balance between the two, the value of helix angle between 15° and 20° is a well choice.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106239"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145270620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel time-optimal feedrate planning method for robots with contour error constraints 一种具有轮廓误差约束的机器人时间最优进给速度规划方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-01 Epub Date: 2025-10-21 DOI: 10.1016/j.mechmachtheory.2025.106227

Qi Qi, Jixiang Yang, Wenhao Li, Han Ding

Existing time-optimal feedrate planning methods for robots typically consider the robot's drive capability limitations, while neglect the limitation of the robot motion accuracy especially the contour accuracy. To address this issue, this paper proposes a novel time-optimal feedrate planning method for robots with contour error constraints. First, a joint tracking error prediction model for the robot considering the control loop and the robot end load is established, and a contour error constraint model for feedrate planning is proposed. Secondly, an improved feedrate squared B-spline is used to transform the feedrate planning problem into a linear optimization problem represented by control points. For jerk constraints, joint torque constraints and contour error constraints that cannot be directly converted into linear constraints, a scaling estimation method is proposed to linearize all nonlinear constraint equations in feedrate planning. Thirdly, a two-step linear programming (LP) method is proposed to solve the time-optimal feedrate planning considering contour error constraints. Comparative experiments conducted on a robot demonstrate that the proposed method can effectively improve the robot's motion efficiency while satisfying the contour error constraints.

现有的机器人时间最优进给规划方法通常考虑机器人的驱动能力限制，而忽略了机器人运动精度特别是轮廓精度的限制。针对这一问题，提出了一种具有轮廓误差约束的机器人时间最优进给速度规划方法。首先，建立了考虑控制环和末端载荷的机器人联合跟踪误差预测模型，并提出了用于进给速度规划的轮廓误差约束模型；其次，利用改进的进给速度平方b样条将进给速度规划问题转化为由控制点表示的线性优化问题；针对不能直接转化为线性约束的抽动约束、关节力矩约束和轮廓误差约束，提出了一种尺度估计方法，将进给速度规划中的所有非线性约束方程线性化。第三，提出了一种考虑轮廓误差约束的两步线性规划方法来求解时间最优进给速度规划问题。在机器人上进行的对比实验表明，该方法在满足轮廓误差约束的情况下，有效地提高了机器人的运动效率。

{"title":"A novel time-optimal feedrate planning method for robots with contour error constraints","authors":"Qi Qi, Jixiang Yang, Wenhao Li, Han Ding","doi":"10.1016/j.mechmachtheory.2025.106227","DOIUrl":"10.1016/j.mechmachtheory.2025.106227","url":null,"abstract":"<div><div>Existing time-optimal feedrate planning methods for robots typically consider the robot's drive capability limitations, while neglect the limitation of the robot motion accuracy especially the contour accuracy. To address this issue, this paper proposes a novel time-optimal feedrate planning method for robots with contour error constraints. First, a joint tracking error prediction model for the robot considering the control loop and the robot end load is established, and a contour error constraint model for feedrate planning is proposed. Secondly, an improved feedrate squared B-spline is used to transform the feedrate planning problem into a linear optimization problem represented by control points. For jerk constraints, joint torque constraints and contour error constraints that cannot be directly converted into linear constraints, a scaling estimation method is proposed to linearize all nonlinear constraint equations in feedrate planning. Thirdly, a two-step linear programming (LP) method is proposed to solve the time-optimal feedrate planning considering contour error constraints. Comparative experiments conducted on a robot demonstrate that the proposed method can effectively improve the robot's motion efficiency while satisfying the contour error constraints.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"217 ","pages":"Article 106227"},"PeriodicalIF":4.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0