Mechanism and Machine Theory最新文献

{"title":"Machine learning-driven innovation design of clustered tensegrity continuum robot","authors":"Xincui Shi,&nbsp;Qi Yang,&nbsp;Kaiwen Hu,&nbsp;Binbin Lian,&nbsp;Yimin Song,&nbsp;Rongjie Kang,&nbsp;Tao Sun","doi":"10.1016/j.mechmachtheory.2025.106155","DOIUrl":"10.1016/j.mechmachtheory.2025.106155","url":null,"abstract":"<div><div>Tensegrity structures have the advantage of superior deformation ability and high load-to-weight ratio, making them potential candidates for cable-driven continuum robot design. However, designing a clustered tensegrity continuum robot is still challenging due to the difficulty in modeling the tensegrity structure. In this study, we propose an innovation design method for a clustered tensegrity continuum robot based on machine learning (ML). Our ML-driven design method includes topology design of the clustered tensegrity continuum robot using genetic algorithm (GA) and deep reinforcement learning (DRL) approach, and driving law design (motion planning) of the continuum robot using deep reinforcement learning. We emphasize the obstacle avoidance and reaching point motion as one of the most important challenges for a cable-driven continuum robot and design the topology and driving law of the clustered tensegrity continuum robot through ML-based approach. This study demonstrates the applicability of tensegrity structures in the field of clustered tensegrity continuum robot design and illustrates the feasibility of using machine learning in the design of clustered tensegrity continuum robot.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106155"},"PeriodicalIF":4.5,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144772540","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}

{"title":"A review of dynamics-based failure modeling and diagnosis techniques for gear systems","authors":"Yang Liu ,&nbsp;Zheng’ang Shan ,&nbsp;Haiying Liang ,&nbsp;Qingyang Sun ,&nbsp;Hui Ma","doi":"10.1016/j.mechmachtheory.2025.106166","DOIUrl":"10.1016/j.mechmachtheory.2025.106166","url":null,"abstract":"<div><div>Gear systems are critical in industrial and military applications but prone to failures under harsh conditions, leading to economic losses and safety risks. This paper provides a comprehensive review of dynamics-based failure modeling and diagnosis techniques for gear systems. It systematically evaluates three modeling approaches: analytical methods (efficient but limited to simple systems), lumped parameter models (balance efficiency and multi-DOF dynamics), and finite element methods (high accuracy but computationally intensive). Hybrid strategies integrating these methods and machine learning are highlighted to enhance computational efficiency and accuracy. Common failure mechanisms, including cracks, pitting, and wear, are analyzed, emphasizing their effects on time-varying mesh stiffness (TVMS) and vibration characteristics. Signal processing and machine learning techniques are discussed for fault feature extraction and diagnosis, with advanced methods like variational modal decomposition and AI-augmented models demonstrating superior performance. Challenges in real-time diagnostics, model generalizability, and coupled failure analysis are identified. Future directions propose hybrid AI-physics models, digital twins, and multi-scale frameworks to improve predictive maintenance. This review bridges theoretical insights and practical applications, offering a foundation for advancing gear system reliability and intelligent fault diagnosis.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106166"},"PeriodicalIF":4.5,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144766734","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}

{"title":"Effect of the secondary suspension and intercar links on the performance of a high-speed train","authors":"Alejandro Bustos ,&nbsp;Higinio Rubio ,&nbsp;Cristina Castejon ,&nbsp;Juan Carlos Garcia-Prada","doi":"10.1016/j.mechmachtheory.2025.106167","DOIUrl":"10.1016/j.mechmachtheory.2025.106167","url":null,"abstract":"<div><div>Multibody simulations are a useful tool for studying railway dynamics in different conditions, as they eliminate the need for expensive tests using actual rolling stock. This paper presents a multibody model of an articulated high-speed train with shared bogies, comprising eight passenger cars and nine bogies, that is implemented in Universal Mechanism. The train's critical speed under nominal conditions is determined by the presence of limit cycles in the wheelsets' phase plane of lateral motion and by the standard deviation of their lateral displacement. A sensitivity study is then performed to examine the impact of secondary suspension stiffness and intercar link damping on lateral stability at speeds between 250 km/h and 450 km/h. The horizontal stiffness of the secondary suspension significantly affects the critical speed, making the central cars of the train more prone to oscillations. Conversely, the vertical stiffness of air springs and the damping of intercar dampers have a minimal effect on the train's critical speed. The proposed model is a first step in developing the digital twin of a high-speed train.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106167"},"PeriodicalIF":4.5,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144772523","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}

{"title":"A dynamic fast load-bearing contact analysis method of spiral bevel gear tooth surface combined with analog equation method","authors":"Peng Chen,&nbsp;Sanmin Wang,&nbsp;Jia Guo,&nbsp;Haoran Zou,&nbsp;Linlin Liu","doi":"10.1016/j.mechmachtheory.2025.106158","DOIUrl":"10.1016/j.mechmachtheory.2025.106158","url":null,"abstract":"<div><div>The dynamic contact analysis of spiral bevel gear tooth surface is the basis of tooth surface design. In order to avoid the time-consuming process of finite element method(FEM) and the neglect of global tooth surface vibration by analytical method, a new dynamic fast loaded tooth surface contact analysis (DF-LTCA) method is proposed in this study. Firstly, the boundary element and internal node model of spiral bevel gear with adaptive boundary conditions are established to ensure the reusability of each node and unit. Second, elastodynamic partial differential equations for gear tooth surfaces with damped and body forces are formulated as equivalent vibration differential equations using the analog equation method (AEM) within the BEM framework, and solved via AEM’s direct integration method (DAEM) to obtain vibration displacements. Subsequently, a dynamic tooth surface contact model and solution method are established by coupling tooth surface vibration results with static clearance, formed the DF-LTCA method for spiral bevel gears. Finally, numerical examples and experiments are provided to verify the correctness of DF-LTCA.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106158"},"PeriodicalIF":4.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750820","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}

{"title":"Strain energy equivalence-based gravity-induced deformation prediction and accuracy partitioning enhancement of a parallel machining module","authors":"Yuhao He ,&nbsp;Fugui Xie ,&nbsp;Zenghui Xie ,&nbsp;Xin-Jun Liu","doi":"10.1016/j.mechmachtheory.2025.106160","DOIUrl":"10.1016/j.mechmachtheory.2025.106160","url":null,"abstract":"<div><div>Structural errors, gravity-induced deformation and other non-geometrical errors simultaneously affect the accuracy of machining equipment. On the one hand, separating gravity-induced deformation from the total pose error is very difficult, which makes the identification of structural errors lacks reliable pose error data. On the other hand, the pose error caused by the other non-geometrical errors is often overlooked in calibration, and it will generate a random disturbance to the pose error caused by structural errors, which makes the error compensation effect worsen as the calibration region expands. In this article, a gravity-induced deformation prediction model based on strain energy equivalence criterion is proposed, which reduces the maximum and mean gravity-induced deformation prediction errors by 55.00 % and 65.32 % in simulation. On this basis, the error model of a five-axis parallel machining module considering gravity-induced deformation is established. Then, an accuracy partitioning enhancement method is proposed, in which the workspace is divided into eight sub-regions and 19 transition regions. A continuous transition function without poles is designed, which guarantees the continuity of structural errors among sub-regions without large fluctuations in transition regions. The pose error caused by structural errors is obtained by removing the predicted gravity-induced deformation from the measured total pose error. The structural errors in sub-regions and transition regions are obtained through the identification process and transition function, respectively, and are compensated into the inverse kinematic model separately. Then, the predicted gravity-induced deformation is compensated into command poses. After accuracy partitioning enhancement with the proposed method to consider gravity-induced deformation, the maximum/mean position error was reduced from 0.1266 mm/0.0238 mm to 0.0548 mm/0.0148 mm, and the maximum/mean posture error was reduced from 0.0897°/0.0280° to 0.0537°/0.0215° compared to the kinematic calibration method that does not apply the accuracy partitioning enhancement method. An S-shaped test piece was machined, and the maximum/mean error of the measuring points was reduced from 0.0817 mm/0.0253 mm to 0.0581 mm/0.0158 mm. The experimental results verify the effectiveness of the gravity-induced deformation prediction model and accuracy partitioning enhancement method. The proposed method can also be applied to other equipment with parallel kinematics.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106160"},"PeriodicalIF":4.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750819","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}

{"title":"A generalized approach for topological design of parallel mechanisms featuring symbolic forward kinematics and motion decoupling using motion-decoupling branches","authors":"Ju Li ,&nbsp;Huiping Shen ,&nbsp;Yinan Zhao ,&nbsp;Jun-jie She ,&nbsp;Qingmei Meng","doi":"10.1016/j.mechmachtheory.2025.106159","DOIUrl":"10.1016/j.mechmachtheory.2025.106159","url":null,"abstract":"<div><div>Designing parallel mechanism (PM) with symbolic forward kinematics (SFK) and motion decoupling (MD) is highly beneficial for subsequent tasks such as real-time control, motion trajectory planning, dimensional synthesis, error analysis, and dynamic analysis. Inspired by first principles, using directly from motion-decoupling branch (MDB) as design units that enables PM to simultaneously achieve SFK and MD, this paper proposes a generalized topological design approach for PMs based on degrees of freedom (DOF) and position and orientation characteristics (POC) as fundamental functions, with SFK and MD as performance indicators. First, nine simple and ten hybrid MDBs are introduced. Second, a general approach for PM topological design using MDBs is proposed. This approach can covers two types of PMs: Type I—designing a PM consisting of MDB with the number of actuated pairs DOF₀ (DOF₀ &lt; DOF) and end-effector POC, along with (DOF - DOF₀) unconstrained branches, followed by topological verification. Type II—first designing at least one MDB and one or more constrained branches, then assembling them into various PMs, and finally obtaining the DOF and POC of the series of PMs through topological analysis for classification and application. Third, five examples, with total eleven novel designed 3-DOF PMs with different type of POCs, are provided to illustrate the design process of general over-constrained PMs using the approach. Finally, guided by the approach, three conditions achieving AI-based topology design for PMs using MDBs are suggested, and the preliminary results for AI-based topology design of 2-DOF 1T1R novel PMs are also discussed.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106159"},"PeriodicalIF":4.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144739594","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}

{"title":"Design, modeling and analysis of a novel (3+1)-DOF multi-loop coupled mechanism with configurable moving platform","authors":"Jiantao Yao ,&nbsp;Hanjun Deng ,&nbsp;Jingyao Zhang ,&nbsp;Yuan Jiang ,&nbsp;Bo Hu","doi":"10.1016/j.mechmachtheory.2025.106162","DOIUrl":"10.1016/j.mechmachtheory.2025.106162","url":null,"abstract":"<div><div>This paper presents a novel (3 + 1)-DOF multi-loop coupled mechanism with configurable moving platform, which has the capability to simultaneously actuate the motion of posture adjustment and operation motion of the distal end, the ability of unlimited rotation in a single dimension and maintenance of a fixed rotation center. In contrast to the design of serially linking the posture control and operation mechanisms, this novel mechanism achieves operation motion of distal end and posture adjustment motion in same time through relative motions between the branches. This novel design places the actuators at the proximal end of the mechanism, resolving issues like gravity center shift and wiring complexities. First, we introduce the concept design of this multi-loop coupled mechanism in conjunction with the conception of generalized parallel mechanism. Through kinematic analysis and performance evaluation encompassing workspace, singularity and force transmission, we determine design parameters and prototype mechanism design to ensure effective motions even in the presence of manufacturing errors. Finally, the prototype and experiments are conducted to validate the effectiveness of the proposed mechanism design.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"215 ","pages":"Article 106162"},"PeriodicalIF":4.5,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722962","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}

{"title":"Trajectory planning and active dynamic balancing for highly dynamic handling tasks, a comparative study","authors":"Christian Mirz ,&nbsp;Burkhard Corves ,&nbsp;Yukio Takeda ,&nbsp;Mathias Huesing","doi":"10.1016/j.mechmachtheory.2025.106147","DOIUrl":"10.1016/j.mechmachtheory.2025.106147","url":null,"abstract":"<div><div>To achieve both energy efficiency and high positioning accuracy, dynamic manipulation tasks such as those found in the packaging industry require lightweight, rigid robotic systems with a high payload-to-weight ratio. Parallel robots are well suited to these requirements due to their kinematic design, with a base-mounted drive system that minimizes inertia. Among them, the Delta robot is the most widely used in such applications. In many industrial applications, it is necessary to operate the robot at reduced speeds or include dwell times in the motion planning to allow vibrations to subside. This helps to maintain accuracy and prevents fatigue and wear of mechanical components. While many studies investigate individual vibration reduction methods, a comprehensive comparison, both theoretical and experimental, is missing, particularly in the context of highly dynamic tasks. This publication addresses this gap by presenting a theoretical analysis of two vibration reduction strategies: trajectory smoothing and dynamic balancing. Furthermore, an experimental validation using a Delta robot in a representative pick-and-place scenario is provided to illustrate the effectiveness, trade-offs, and challenges associated with applying these methods in real-world scenarios.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"214 ","pages":"Article 106147"},"PeriodicalIF":4.5,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714290","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}

{"title":"Design and synthesis of four-bar mechanisms with integrated springs for nonlinear stiffness applications","authors":"Vu Linh Nguyen","doi":"10.1016/j.mechmachtheory.2025.106152","DOIUrl":"10.1016/j.mechmachtheory.2025.106152","url":null,"abstract":"<div><div>This paper presents the design and synthesis of four-bar mechanisms with integrated springs for applications requiring nonlinear stiffness. The proposed method systematically identifies a total of 42 distinct mechanism configurations, each composed of a planar four-bar linkage with strategically placed springs to achieve specific torque-angle profiles. The method combines free-body diagram analysis with particle swarm optimization to determine the optimal geometric and spring parameters that minimize the error between the desired and actual torque outputs over a specified angular range. The significance of this method lies in the practical realization of nonlinear stiffness characteristics using simple and compact structures. Numerical simulations across various target stiffness profiles demonstrate the accuracy and adaptability of the synthesized mechanisms with minimal torque deviations. Physical prototypes and experimental validation further confirm the effectiveness of the method, highlighting its potential in applications such as compliant actuators, adaptive robotic manipulators, and vibration isolators.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"214 ","pages":"Article 106152"},"PeriodicalIF":4.5,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703501","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}

{"title":"Enhanced lumped stiffness model for industrial robots under multi-axial loading: Trade-off between the model complexity and positional accuracy","authors":"Eldho Paul ,&nbsp;Riby Abraham Boby ,&nbsp;Hariharan Krishnaswamy ,&nbsp;Alexandr Klimchik","doi":"10.1016/j.mechmachtheory.2025.106133","DOIUrl":"10.1016/j.mechmachtheory.2025.106133","url":null,"abstract":"<div><div>The elastostatic calibration of industrial robots using reduced order stiffness models predominantly relies on joint compliance. The contribution of link compliance ignored in these models assumes significance, especially when the end-effector employs external loads. The presented work overcomes the limitation by proposing a simpler reduced order model encompassing joint and link compliance. The proposed model has only nine parameters compared to an existing model with twenty-six parameters. A novel top-down approach is adopted for identifying these nine parameters, wherein the parameters are lumped to accurately model the end-effector deflection under multi-axial loading. A dedicated experimental setup involving two ABB IRB 7600-500 robots was used to validate the model. The performance of the nine parameter model is akin to other sophisticated models involving many parameters. The calibration resulted in a 91% reduction in position error. The model and identification strategies are generic and can be adapted to any similar serial robot. The compatibility of the identified parameters was tested using another robot of the same (make) specification. The error predictions were in a similar order, confirming the robustness of the approach.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"214 ","pages":"Article 106133"},"PeriodicalIF":4.5,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144696746","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}