Mechanism and Machine Theory最新文献_第4页

Dynamic modeling and parameter optimization for a pneumatic-driven peristaltic origami robot 气动蠕动折纸机器人动力学建模及参数优化

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-29 DOI: 10.1016/j.mechmachtheory.2025.106326

Kunming Ren , Tingting Yuan , Jinyang Liu

Origami-inspired soft pneumatic actuators provide adaptable and robust solutions for mechanical design, especially in pneumatic-driven peristaltic robots. Accurate dynamic simulation of such systems is essential for design and performance improvement, yet existing studies remain limited. This paper proposes an enhanced dynamic model that improves upon the bar and hinge approach by employing a consistent mass matrix to accurately compute the moment of inertia of origami panels, achieving both high precision and computational efficiency. The proposed framework incorporates coupling between origami structures and multibody dynamics, while accounting for frictional contact, pneumatic actuation and general interactions, thereby accommodating complex mechanical assemblies. To validate the model, experimental studies on peristaltic origami robots are conducted, demonstrating excellent agreement with simulation results. The experiments involve fabricating Kresling-type origami actuators using laminated carbon fiber and fabric, followed by crease parameter calibration. Furthermore, the motion capabilities of an expanded origami robot are analyzed and optimized for both one-dimensional and two-dimensional locomotion. The results provide valuable insights into the design of origami-based robotic systems and highlight the effectiveness and versatility of the proposed dynamic modeling approach.

折纸启发的软气动执行器为机械设计提供了适应性强的鲁棒解决方案，特别是在气动驱动的蠕动机器人中。精确的动态仿真对系统的设计和性能改进至关重要，但现有的研究仍然有限。本文提出了一种改进的动力学模型，该模型在杆铰法的基础上，采用一致质量矩阵精确计算折纸板的转动惯量，达到了高精度和高效率的目的。提出的框架结合了折纸结构和多体动力学之间的耦合，同时考虑了摩擦接触、气动驱动和一般相互作用，从而适应复杂的机械组件。为了验证该模型，对蠕动折纸机器人进行了实验研究，结果与仿真结果吻合良好。实验采用叠层碳纤维和织物制备了kresling型折纸驱动器，并对折痕参数进行了标定。在此基础上，对扩展型折纸机器人的一维和二维运动能力进行了分析和优化。研究结果为基于折纸的机器人系统的设计提供了有价值的见解，并突出了所提出的动态建模方法的有效性和多功能性。

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引用次数: 0

Mapping mechanical synthesis to a trainable task: A neural network approach for generalized parallel mechanisms 将机械综合映射为可训练任务：广义并联机构的神经网络方法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-27 DOI: 10.1016/j.mechmachtheory.2025.106337

Zhihao Xia , Xinhua Lao , Chunxu Tian , Dan Zhang

Generalized parallel mechanisms (GPMs) with multiloop coupling have garnered considerable attention because of their structural attributes, including high strength, superior stability, and strong scalability. However, existing synthesis methods face limitations when addressing multiloop coupled structures. Conventional approaches are typically confined to scenarios with fewer loops, involving complex and inefficient analysis processes. To overcome these challenges, this paper proposes a novel synthesis method based on a topological mapping neural network (TMNN). By mapping the topological structure of a GPM onto a neural network, the motion transmission process of the mechanism is equivalent to the forward propagation of neurons, thereby transforming a traditionally intractable problem into a trainable optimization task within a neural network. This paper elaborates on the theoretical foundation and network architecture design of the proposed method. Its feasibility and effectiveness are validated through experiments. While future work will focus on enhancing computational efficiency, this innovative topological mapping approach provides a crucial theoretical and practical foundation for the efficient synthesis of multiloop coupled GPMs.

具有多环耦合的广义并联机构（gpm）因其高强度、高稳定性和强可扩展性等结构特性而受到广泛关注。然而，现有的合成方法在处理多环耦合结构时存在局限性。传统的方法通常局限于循环较少的场景，涉及复杂和低效的分析过程。为了克服这些挑战，本文提出了一种基于拓扑映射神经网络（TMNN）的合成方法。通过将GPM的拓扑结构映射到神经网络上，将机构的运动传递过程等效为神经元的正向传播，从而将传统的难解问题转化为神经网络内可训练的优化任务。本文详细阐述了该方法的理论基础和网络架构设计。通过实验验证了该方法的可行性和有效性。虽然未来的工作将集中在提高计算效率上，但这种创新的拓扑映射方法为高效合成多环耦合gpm提供了重要的理论和实践基础。

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引用次数: 0

Improved non-singular fast terminal sliding mode control for 4DOF ship-mounted rotary cranes 改进的四自由度船载旋转起重机非奇异快速终端滑模控制

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-24 DOI: 10.1016/j.mechmachtheory.2025.106329

Zijie Wu , Huimin Ouyang , Menghua Zhang , Tongtong Liu

The precise control of ship-mounted rotary cranes is critically challenged by their inherent underactuation, strong nonlinear coupling between boom motion and payload swing, and persistent wave-induced ship disturbances. While advanced control strategies (e.g., sliding mode control, adaptive control) have been developed, many existing designs either rely on model linearization, lack rigorous finite-time stability guarantees for the fully coupled system, or exhibit limited robustness against compound time-varying disturbances. To address these gaps, this paper proposes a novel adaptive non-singular fast terminal sliding mode (ANFTSM) controller. Its core innovation is a newly constructed sliding surface that explicitly integrates errors from both actuated and underactuated states, ensuring the finite-time convergence of all system variables. Enhanced robustness is achieved through adaptive laws that estimate and compensate for unknown friction and wind disturbances in real time, without requiring prior knowledge of disturbance bounds. Importantly, the controller is derived directly from the full nonlinear dynamics, forgoing any linearization, and its global stability is rigorously proven via Lyapunov theory. Extensive comparative experiments demonstrate that the proposed controller outperforms established benchmarks (PD-SMC, OFC, BBC). Under nominal conditions, it achieves the fastest convergence times (8.06 [s] for luffing, 8.56 [s] for rotation) and superior swing suppression, limiting the maximum radial sway to merely 2.05 [deg]. Furthermore, it maintains excellent robustness against significant parameter variations (e.g., load mass, cable length) and non-zero initial swing angles. These performance gains are accomplished with the lowest total control effort (70 [N · m · s]) among all compared methods, confirming its superior energy efficiency alongside outstanding control performance.

船载旋转起重机固有的欠驱动、臂架运动与载荷摆动之间强烈的非线性耦合以及持续的波浪扰动对其精确控制提出了严峻的挑战。虽然先进的控制策略（如滑模控制、自适应控制）已经开发出来，但许多现有的设计要么依赖于模型线性化，对完全耦合系统缺乏严格的有限时间稳定性保证，要么对复合时变扰动的鲁棒性有限。为了解决这些问题，本文提出了一种新的自适应非奇异快速终端滑模控制器（ANFTSM）。其核心创新是新构建的滑动面，该滑动面明确地集成了驱动和欠驱动状态的误差，确保了所有系统变量的有限时间收敛。增强的鲁棒性是通过自适应律来实现的，该律实时估计和补偿未知的摩擦和风扰动，而不需要事先知道扰动边界。重要的是，控制器是直接从完全非线性动力学推导出来的，放弃了任何线性化，并通过李雅普诺夫理论严格证明了其全局稳定性。大量的对比实验表明，所提出的控制器优于既定的基准（PD-SMC， OFC， BBC）。在标称条件下，它实现了最快的收敛时间（变幅8.06 [s]，旋转8.56 [s]）和优越的摆幅抑制，将最大径向摆动限制在2.05[度]。此外，它对重大参数变化（例如，负载质量，电缆长度）和非零初始摆角保持出色的鲁棒性。在所有比较的方法中，这些性能增益是以最低的总控制努力（70 [N · m · s]）完成的，证实了其优越的能源效率和出色的控制性能。

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引用次数: 0

Encircling singularities of a serial robot to find alternative inverse-kinematic solutions 串联机器人的绕奇点求逆解

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-24 DOI: 10.1016/j.mechmachtheory.2025.106314

Paul Milenkovic , Zinan Wang , Jose I Rodriguez

A singularity encirclement procedure determines all feasible displacement paths of a 6-axis serial-link robot radiating from isolated, coincident or nearly coincident singularities. Points on these paths supply alternative inverse-kinematic solutions of the robot in the neighborhood of these singularities. The encirclement maintains a constant sum-of-squared joint-angle distance from the associated path bifurcation. This is accomplished by following an intended displacement path of the robot in coordination with a deviation from this path. Where the encircling path crosses through zero deviation identifies a point on a feasible zero-deviation robot path radiating from the bifurcation. Differing from the prior applications of this method, which do not include robots, some but not all coincident singularity pairs require two deviation directions. A novel procedure employing matrix regularization facilitates this identification by bringing nearly coincident singularities into coincidence and by calculating multiple deviations direction corresponding to multiple coincident singularities.

奇点包络程序确定了六轴串联机器人从孤立奇点、重合奇点或近重合奇点辐射出的所有可行位移路径。这些路径上的点提供了机器人在这些奇异点附近的备选逆运动学解。包围圈与相关的路径分岔保持恒定的平方和联合角距离。这是通过协调机器人的预定位移路径并偏离该路径来实现的。当绕行路径经过零偏差时，在从分岔辐射的可行零偏差机器人路径上确定一个点。与以往不包括机器人的应用不同，一些但不是所有的重合奇点对都需要两个偏差方向。一种采用矩阵正则化的新方法通过将几乎重合的奇点转化为重合奇点，并通过计算多个重合奇点对应的多重偏离方向来简化这种识别。

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引用次数: 0

Singularity conditions from a kinetostatic analysis of a new parallel robot for human balance and gait rehabilitation 一种新型人体平衡与步态康复并联机器人的动静力学分析

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-22 DOI: 10.1016/j.mechmachtheory.2025.106328

Paul Diego, Erik Macho, Francisco J. Campa, Saioa Herrero, Mikel Diez, Javier Corral, Charles Pinto

This paper presents a novel device for the rehabilitation of balance and gait functions in patients with neurological disorders. The device is composed of two sensorized footplates, one for each foot of the patient, which are driven by two identical 4-DOF parallel manipulators. The mobility and kinematic analyses of this new parallel manipulator are conducted for the first time, including the resolution of the inverse position problem and the formulation of the overall Jacobian matrix. Then, a simplification of the kinetostatic problem is proposed, which not only reduces the computational cost but also leads to a reduced matrix that enhances the singularity analysis process. Using this matrix and placing emphasis on the geometric interpretation of the singularity conditions, a thorough characterization of them is carried out, which has proven useful for the working mode selection and for visual verification of the rehabilitation trajectories proposed in the path planning process. The paper concludes with the presentation of a prototype intended to validate the usefulness of this device in the rehabilitation field.

本文介绍了一种用于神经系统疾病患者平衡和步态功能康复的新型装置。该装置由两个传感器踏板组成，每只脚对应一个踏板，由两个相同的4-DOF并联机械手驱动。首次对该并联机器人进行了运动学和机动性分析，求解了该并联机器人的位置逆问题，建立了该并联机器人的总体雅可比矩阵。然后，提出了一种运动静力问题的简化方法，不仅减少了计算量，而且简化了矩阵，从而提高了奇异性分析的过程。利用该矩阵并着重于奇点条件的几何解释，对其进行了彻底的表征，这对工作模式的选择和路径规划过程中提出的修复轨迹的视觉验证是有用的。论文最后提出了一个原型，旨在验证该设备在康复领域的实用性。

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引用次数: 0

Integrated geometric modeling, meshing behavior analysis, and experimental prototype validation of arc-cycloid external gear pairs 弧摆线外齿轮副几何建模、啮合特性分析及实验样机验证

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-19 DOI: 10.1016/j.mechmachtheory.2025.106323

Zhigang Wu , Xuan Li , Qi Sun , Minglu Zhu , Tao Chen , Lining Sun

This study presents theoretical design methods and conducts systematic performance analysis for an arc-cycloid external gear pair. The pairing consists of a circular-arc pinion and an enveloping-generated cycloid gear, achieving conjugate meshing via continuous line contact. This design prevents undercutting observed in involute gears and enables higher transmission ratios under identical center distance and structural constraints. Mathematical models of the gears are established using differential geometry and spatial meshing theory. Spatial contact trajectories, pressure angles, and induced normal curvature are computationally analyzed with dependencies quantified. A hybrid loaded tooth contact analysis (LTCA) methodology is developed through the integration of Boussinesq’s elastic half-space theory and the influence coefficient method. This approach enables precise calculation of contact stress distributions across loaded tooth surfaces. The theoretical LTCA model is validated by finite element analysis (FEA), with computational results showing excellent agreement against analytical solutions. Experimental verification is conducted on a purpose-built test rig. Transmission stability and band-shaped contact patterns are confirmed through precise measurements. Consistency is demonstrated between experimental measurements and simulation predictions, independently validating the proposed methodology. The gear pair demonstrates significant potential for applications demanding compact, high-ratio power transmission.

提出了弧摆线外齿轮副的理论设计方法，并进行了系统的性能分析。该啮合由圆弧小齿轮和包络生成摆线齿轮组成，通过连续的线接触实现共轭啮合。这种设计防止在渐开线齿轮中观察到的下切，并在相同的中心距离和结构约束下实现更高的传动比。利用微分几何和空间啮合理论建立了齿轮的数学模型。对空间接触轨迹、压力角和诱导法向曲率进行了计算分析，并对相关关系进行了量化。将Boussinesq弹性半空间理论与影响系数法相结合，提出了一种混合载荷齿接触分析方法。这种方法可以精确计算齿面接触应力分布。通过有限元分析（FEA）验证了理论LTCA模型，计算结果与解析解具有良好的一致性。在专门搭建的试验台上进行了实验验证。通过精确的测量，确定了传输稳定性和带状接触模式。一致性证明了实验测量和模拟预测之间的一致性，独立验证了所提出的方法。齿轮副显示了显著的潜力应用要求紧凑，高比率的动力传输。

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引用次数: 0

Rigid-foldable tapered origami patterns derived from type III Bricard octahedra 可刚性折叠的锥形折纸图案源自第三型布里卡八面体

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-18 DOI: 10.1016/j.mechmachtheory.2025.106325

Yucai Hu, Yongliang Luo

While origami has long served as physical analogs for classical mechanisms, few large origami patterns are directly derived from these kinematic systems. This paper presents single-degree-of-freedom rigid-foldable tapered origami patterns based on the type III Bricard octahedron (BOIII), a foundational flexible polyhedral mechanism. Building on extending BOIII into tubular structures, we demonstrate how kinematic equivalence and interchangeability between isogram and antiisogram enable the development of rigid-foldable configurations with bilateral origami-patterned surfaces. The rigid foldability of the BOIII and its derived crease patterns is validated through the consistent application of facet compatibility conditions. Using symmetric BOIII units, tapered origami patterns of spiral, zigzag, and hybrid profiles are constructed. Notably, the spiral pattern featuring two tapering vertices mimics natural spirals in ammonites and snails. An inverse design approach is established to generate tapered crease patterns, ensuring their bottom boundary edges conforms to the target planar curve at a prescribed fold angle. This mechanism-based approach expands the design space of rigidly and flat-foldable quadrilateral mesh origami patterns by incorporating the tapering feature, offering potential applications in deployable aerospace structures, reconfigurable robotics, and metamaterials.

虽然折纸长期以来一直是经典机构的物理类比，但很少有大型折纸图案直接来自这些运动学系统。提出了一种基于三型布里卡德八面体（BOIII）的单自由度刚性可折叠锥形折纸图案。在将BOIII扩展到管状结构的基础上，我们展示了等线和反等线之间的运动等效性和互换性如何使具有双边折纸图案表面的刚性可折叠构型得以发展。BOIII及其衍生折痕图的刚性可折叠性通过面相容性条件的一致性应用得到验证。使用对称BOIII单元，锥形折纸图案的螺旋，之字形，和混合轮廓被构造。值得注意的是，螺旋图案具有两个逐渐变细的顶点，模仿了鹦鹉螺和蜗牛的天然螺旋。建立了一种生成锥形折痕图的反设计方法，保证折痕图的底边在规定的折角下符合目标平面曲线。这种基于机制的方法通过结合锥形特征扩展了刚性和可平折四边形网格折纸图案的设计空间，在可展开的航空航天结构、可重构机器人和超材料中提供了潜在的应用。

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引用次数: 0

An efficient algorithm for evaluating kinematic closed-loop constraint forces of flexible multibody systems 一种评估柔性多体系统运动闭环约束力的有效算法

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-18 DOI: 10.1016/j.mechmachtheory.2025.106324

Qixing Yue , Xiaoting Rui , Jianshu Zhang , Kuankuan Gang , Baichen Yang , Shengwei Miao

The formulation of closed-loop flexible multibody systems can be accomplished via the reduced transfer matrix method, which employs joint coordinates, elastic modal coordinates, and a tree-based topology description achieved by imaginarily cutting specific joints, resulting in a minimal set of generalized coordinates for the forward dynamic analysis utilizing recursive procedures. An efficient algorithm is proposed in this paper to eliminate redundant evaluations for kinematic closed-loop constraint forces within these recursive procedures. The transfer equations and recursive relationship of the accelerations for flexible body components are reformulated in lightweight forms characterized by the minimal sets of closed-loop constraint forces. Complementarily, the kinematic closed-loop constraint equations are reformulated in lightweight manners upon the minimal sets of closed-loop constraint forces, whereby the corresponding constraint forces are evaluated through redundancy-free computations. Three numerical examples are finally presented to illustrate the effectiveness, versatility, and efficiency of the proposed algorithm. It can be concluded that the proposed algorithm provides a computationally efficient alternative to the recursive solution procedures for the forward dynamic analysis of flexible multibody systems.

闭环柔性多体系统的表述可以通过简化传递矩阵法来完成，该方法采用关节坐标、弹性模态坐标和基于树的拓扑描述，通过想象切割特定的关节来实现，从而产生最小的广义坐标集，用于利用递推程序进行正动力分析。本文提出了一种有效的算法来消除这些递归过程中运动学闭环约束力的冗余评估。将柔性体各部件的加速度传递方程和递推关系以闭环约束力最小集的轻量化形式重新表述。此外，在闭环约束力最小集的基础上，以轻量化的方式重新表述了运动学闭环约束方程，通过无冗余计算来评估相应的约束力。最后给出了三个数值算例，说明了该算法的有效性、通用性和高效性。结果表明，该算法为柔性多体系统的正演动力学分析提供了一种计算效率高的替代方法。

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引用次数: 0

Optimal design of high load-to-mass ratio for a class of multi-locomotion tensegrity mobile robots 一类多运动张拉整体移动机器人的高载荷质量比优化设计

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-18 DOI: 10.1016/j.mechmachtheory.2025.106327

Qi Yang , Kaiwen Hu , Xincui Shi , Jinzhu Zhou

Achieving a high load-to-mass ratio is a critical yet challenging goal for multi-locomotion tensegrity robots, as it dictates their practical load-carrying capacity but is difficult to optimize due to the complex model and redundant parameters of the robots. In this study, we propose an optimal design method that significantly enhances load-to-mass ratio for a class of multi-locomotion tensegrity mobile robots. Our key innovation lies in a holistic approach that integrates a finite element-based stiffness model, which is derived from force-deformation mapping. The effect of key parameters of the robot on stiffness is clarified. The established stiffness model subsequently guides a multi-constrained optimization framework, which is tailored to acquire high load-to-mass ratio across the entire locomotion process. In particular, the complex method is employed to solve the optimization model. The result is a groundbreaking improvement: our optimized design achieves a load-to-mass ratio of up to 7.60, which significantly surpasses all previously documented values for comparable mobile robots. Finally, experiments on the load-to-mass ratio of a prototype are conducted to demonstrate the correctness and rationality of the proposed optimal design method.

实现高负载质量比是多运动张拉整体机器人的一个关键而具有挑战性的目标，因为它决定了机器人的实际承载能力，但由于机器人的复杂模型和冗余参数而难以优化。在本研究中，我们提出了一种优化设计方法，显著提高了一类多运动张拉整体移动机器人的载荷质量比。我们的关键创新在于集成了基于有限元的刚度模型的整体方法，该模型来源于力-变形映射。阐明了机器人关键参数对刚度的影响。建立的刚度模型随后指导多约束优化框架，从而在整个运动过程中获得高载荷质量比。特别地，采用复形法求解优化模型。结果是一个突破性的改进：我们优化的设计实现了高达7.60的负载质量比，这大大超过了所有以前记录的类似移动机器人的值。最后，通过某样机的载荷质量比试验，验证了所提优化设计方法的正确性和合理性。

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引用次数: 0

Synthesis at the output port of compliant mechanisms through the instantaneous geometric invariants 通过瞬时几何不变量在柔顺机构的输出端进行综合

IF 4.5 1区工程技术 Q1 ENGINEERING, MECHANICAL

Mechanism and Machine Theory

Pub Date : 2025-12-17 DOI: 10.1016/j.mechmachtheory.2025.106320

M. Verotti

Recently, the instantaneous geometric invariants have proved to be a fundamental tool for the analysis of the motion generated by flexure hinges. In this paper, the invariants are applied to the synthesis of compliant mechanisms at the output port level. The motion of the moving plane associated to the output port is described through fundamental geometric entities, that are the inflection circle, the cubic of stationary curvature, and its derivative. The proposed synthesis procedure aims to reshape the output port to embody the special points on the plane, that are the Ball’s and the Burmester’s points, approximating straight and circular paths to the third and to the fourth order, respectively. The method is implemented for the design of a compliant mechanism and numerical simulations are conducted to verify the theoretical results. A discussion of the advantages and disadvantages of the method is presented.

近年来，瞬时几何不变量已被证明是分析柔性铰链运动的基本工具。本文将不变量应用于输出端口级柔顺机构的综合。与输出端口相关的运动平面的运动是通过基本的几何实体来描述的，这些实体是拐点圆、静止曲率的三次及其导数。所提出的合成过程旨在重塑输出端口，以体现平面上的特殊点，即Ball点和Burmester点，分别近似于三阶和四阶的直线和圆形路径。将该方法应用于柔性机构的设计，并通过数值仿真验证了理论结果。讨论了该方法的优缺点。

引用次数: 0