Mechanism and Machine Theory最新文献_第3页

The friction-limited end-effector motion resolution of tendon-actuated and continuum robots 腱驱动机器人和连续机器人的摩擦限制末端执行器运动分辨率

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-23 DOI: 10.1016/j.mechmachtheory.2024.105814

Neel Shihora, Nabil Simaan

{"title":"The friction-limited end-effector motion resolution of tendon-actuated and continuum robots","authors":"Neel Shihora, Nabil Simaan","doi":"10.1016/j.mechmachtheory.2024.105814","DOIUrl":"10.1016/j.mechmachtheory.2024.105814","url":null,"abstract":"<div><div>Force and motion transmission losses can significantly affect the kinematics and performance of wire-actuated robots. In addition to degrading the kinematic model, they can produce hysteresis (dead-zone) effects whereby the motion of the actuators produces no motion of the end effector. This paper presents a modeling framework that can be used at the design stage to evaluate the effects of these transmission losses. Considerations for modeling the dead-zone effects of end-effector motion are used to define a performance measure that quantifies the quality of a given design within a workspace. This design measure should be used in conjunction with the traditional kinematics and statics-based measures to reflect the expected performance of an integrated wire-actuated robot with its actuation lines and actuation unit. To illustrate our approach, we present a model of a wire-actuated snake-like robot with an articulated backbone made up of ball-and-socket joints. The results and methodology reported in this paper can guide the design of wire-actuated robots in selecting wire-parameters and determining their effects on the expected uncertainty, limiting the friction-limited minimal motion resolution of the end effector.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105814"},"PeriodicalIF":4.5,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142536007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Reducing backward motion of stick-slip piezoelectric actuators using dual driving feet designed by asymmetric stiffness principle 利用非对称刚度原理设计的双驱动脚减少粘滑压电致动器的后向运动

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-21 DOI: 10.1016/j.mechmachtheory.2024.105810

Jie Ling , Hongtao Peng , Yuzhou Duan , Micky Rakotondrabe

{"title":"Reducing backward motion of stick-slip piezoelectric actuators using dual driving feet designed by asymmetric stiffness principle","authors":"Jie Ling , Hongtao Peng , Yuzhou Duan , Micky Rakotondrabe","doi":"10.1016/j.mechmachtheory.2024.105810","DOIUrl":"10.1016/j.mechmachtheory.2024.105810","url":null,"abstract":"<div><div>Stick–slip piezoelectric actuators (SSPEAs) have drawn attention for their features of simple structure and high positioning accuracy. However, the backward motion has always been a major problem that limits driving speed and smoothness. Existing methods mainly focus on control methods and driving signal optimization, while few efforts emphasize mechanical structure optimization. To address this problem from the root of structure design, a novel SSPEA based on the principle of asymmetric stiffness is developed. A dual-driving feet configuration generates phase differences between two feet when feeding sawtooth driving signals. The core idea is that the backward motion of one driving foot can be compensated by another foot making full use of the phase difference due to the asymmetric stiffness compliant mechanism (ASCM). Kinematic and static models are built and the structural dimensions are then determined. Finite element analysis is conducted preliminarily to test the output performance. A physical prototype is fabricated and experimentally verified. Experimental results show the proposed actuator with ASCM achieves smaller backward motion and larger step size ranging from 250 to 1400 Hz driving frequencies compared with traditional triangular compliant mechanism (TTCM). The maximum speed is obtained as 47.2 mm/s with a resolution of <span><math><mrow><mn>0</mn><mo>.</mo><mn>07</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105810"},"PeriodicalIF":4.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142536006","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

Design and tension distribution optimization of a 9-DOF cable-driven parallel spray-painting robot with 3 degrees of redundancy 具有 3 个冗余度的 9-DOF 拉索驱动并联喷涂机器人的设计和张力分布优化

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-19 DOI: 10.1016/j.mechmachtheory.2024.105818

Jiahao Zhao , Bin Zi , Wei Wang , Ming Xie , Huafeng Ding

{"title":"Design and tension distribution optimization of a 9-DOF cable-driven parallel spray-painting robot with 3 degrees of redundancy","authors":"Jiahao Zhao , Bin Zi , Wei Wang , Ming Xie , Huafeng Ding","doi":"10.1016/j.mechmachtheory.2024.105818","DOIUrl":"10.1016/j.mechmachtheory.2024.105818","url":null,"abstract":"<div><div>This paper presents a 9-DOF cable-driven parallel spray-painting robot (CDPSR) with 3 ° of redundancy (DORs) for automated spraying on large, curved surfaces and proposes a feasible cable tension region (FCTR) calculation algorithm for multi-redundant robots. The end effector of the CDPSR consists of two moving platforms connected by a spherical hinge and driven by 12 cables, enabling 9 DOFs of motion (3 for translation and 6 for rotation). Given that the CDPSR has three DORs, a multi-dimensional FCTR vertex calculation algorithm is introduced. The FCTR is an adjacent, continuous, and closed convex hull in every dimension; therefore, the vertices of the FCTR can be determined sequentially and dimensionally. For DOR=3, the vertices on one face of the convex polyhedron are first determined and then extended to adjacent faces until the polyhedron is closed. An experimental prototype of the proposed robot was constructed and experiments on spray trajectory planning and FCTR calculation validation were conducted. The results of the simulations and experiments verified the motion performance of the CDPSR and the accuracy and efficiency of the FCTR calculation algorithm.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105818"},"PeriodicalIF":4.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142536005","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

Identification of non-circular profiles in hydrodynamic journal bearings 识别流体动力轴颈轴承中的非圆形轮廓

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-19 DOI: 10.1016/j.mechmachtheory.2024.105819

Matheus Victor Inacio, Katia Lucchesi Cavalca, Gregory Bregion Daniel

{"title":"Identification of non-circular profiles in hydrodynamic journal bearings","authors":"Matheus Victor Inacio, Katia Lucchesi Cavalca, Gregory Bregion Daniel","doi":"10.1016/j.mechmachtheory.2024.105819","DOIUrl":"10.1016/j.mechmachtheory.2024.105819","url":null,"abstract":"<div><div>Hydrodynamic bearings, especially cylindrical radial plain journal bearings, are widely utilized in industry for their high load capacity and low friction energy losses. However, these bearings are prone to faults such as wear and ovalization, which can deform their circular profile and affect their vibrational response. Detecting these faults is essential to reduce their impact on production. This study introduces a methodology to identify hydrodynamic bearings with non-circular profiles. The bearing model and its numerical solution are implemented using the Finite Volume Method, with the effects of failures incorporated into a rotating system modeled by the Finite Element Method. A dataset is generated to reflect three common failure conditions in industrial applications: wear, ovalization, and a combination of ovalization with wear. The authors used this dataset to train a Multilayer Perceptron (MLP) neural network, which can identify the bearing profile shape based on specific attributes of the dynamic responses. The identification tests for the three fault conditions demonstrated high accuracy, particularly in distinguishing between ovalization and wear.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105819"},"PeriodicalIF":4.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535938","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

Design and optimization of compliant constant-torque mechanisms utilizing arbitrary pre-curved beams 利用任意预弯梁设计和优化顺应式恒扭矩机构

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-18 DOI: 10.1016/j.mechmachtheory.2024.105803

Ke Wu , Qidi Sun , Lifu Liu , Yifan Liu , Gang Zheng , Rui Chen

{"title":"Design and optimization of compliant constant-torque mechanisms utilizing arbitrary pre-curved beams","authors":"Ke Wu , Qidi Sun , Lifu Liu , Yifan Liu , Gang Zheng , Rui Chen","doi":"10.1016/j.mechmachtheory.2024.105803","DOIUrl":"10.1016/j.mechmachtheory.2024.105803","url":null,"abstract":"<div><div>Compliant constant-torque mechanisms (CCTMs) have the potential to be used in precise manipulation and (force or torque) balance devices. In this paper, we propose two types of CCTMs utilizing varying-curvature beams. The stiffness-combination compliant constant-torque mechanisms (SC-CCTMs) are designed by combining positive-stiffness structures and negative-stiffness structures, whereas direct-zero-stiffness compliant constant-torque mechanisms (DZS-CCTMs) are designed by using zero-stiffness structures. In this paper, we develop a comprehensive methodology to analyze the mentioned CCTMs. Based on the methodology, a straight beam and a varying-curvature beam are optimized for negative stiffness and positive stiffness respectively to design SC-CCTMs. Besides, a constant-curvature beam is optimized for zero stiffness to design DZS-CCTMs. Then, the optimized SC-CCTM has the characteristic of adjustable constant-torque, and the optimized DZS-CCTM has a smaller preload range and a wider constant-torque range compared to existing results. Finally, the kinetostatic model has been verified using finite element method (FEM), with an error of less than 3% compared to FEM. The prototype of the optimized DZS-CCTM and SC-CCTM have been fabricated and tested to further verify the feasibility of the proposed design methodology.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105803"},"PeriodicalIF":4.5,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445641","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

Simulating fatigue damage on planar mechanisms considering wear in revolute joints with clearance 模拟平面机构的疲劳损伤，考虑有间隙的旋转接头的磨损问题

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-17 DOI: 10.1016/j.mechmachtheory.2024.105805

M. López-Lombardero , J. Cuadrado , M. Cabello , F. Martinez , D. Dopico , A. López Varela

{"title":"Simulating fatigue damage on planar mechanisms considering wear in revolute joints with clearance","authors":"M. López-Lombardero , J. Cuadrado , M. Cabello , F. Martinez , D. Dopico , A. López Varela","doi":"10.1016/j.mechmachtheory.2024.105805","DOIUrl":"10.1016/j.mechmachtheory.2024.105805","url":null,"abstract":"<div><div>Clearances and wear are present in almost all mechanisms. Their presence leads to degradation of the dynamic behavior of the mechanisms, involving the appearance of vibrations, noise, high forces at the joints, and an increasing fatigue damage.</div><div>To simulate this problem, a flexible multibody model is proposed to efficiently determine the stresses involved, thus avoiding the high computational costs associated with the finite element method. The model considers the mechanical interactions and material degradation processes that affect the stress state, providing a more accurate estimation of fatigue damage. In this work, a methodology is proposed for estimating fatigue damage in mechanisms with clearance joints without the need of simulating all the cycles actually performed.</div><div>The proposed methodology is applied to a planar slider-crank mechanism in which the fatigue undergone by the connecting rod is considered. Results show that clearances strongly affect the fatigue damage of the links. Furthermore, the effect of wear changes the linear behaviour of fatigue damage with respect to the number of cycles, generally producing a higher damage, and changing the critical damage zones in some cases.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105805"},"PeriodicalIF":4.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445639","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

An integrated design method for piezo-actuated compliant mechanisms considering configurations, flexure elements, and actuators 考虑构型、挠性元件和致动器的压电致动顺变机构综合设计方法

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-17 DOI: 10.1016/j.mechmachtheory.2024.105808

Jianhao Lai, Longhuan Yu, Hao Xu, Rixin Wang, Haoyan Zang, Hai Li, Benliang Zhu, Xianmin Zhang

{"title":"An integrated design method for piezo-actuated compliant mechanisms considering configurations, flexure elements, and actuators","authors":"Jianhao Lai, Longhuan Yu, Hao Xu, Rixin Wang, Haoyan Zang, Hai Li, Benliang Zhu, Xianmin Zhang","doi":"10.1016/j.mechmachtheory.2024.105808","DOIUrl":"10.1016/j.mechmachtheory.2024.105808","url":null,"abstract":"<div><div>With the wide application of piezo-actuated compliant mechanisms (PACM) in the nano-positioning domain, it has been a crucial and challenging issue to design optimal PACMs with various design objectives and constraints. In this paper, an integrated design method for the planar PACMs is developed to realize their comprehensive performance optimization, considering the key factors, including mechanical configurations, flexure elements, and piezoelectric actuators (PEA). This method can effectively consider the complicated coupled dynamics between compliant mechanisms and actuators and further accurately predict the actual performance of the PACMs. Utilizing the Pareto optimality idea, the method can efficiently find the performance limits of various alternative configurations and offer the most appropriate design solutions for practical engineering applications. Two nano-positioning stages used for atomic force microscope (AFM) imaging are designed from alternative combinations of four configurations, five types of actuators, and twelve types of flexure hinges to illustrate the detailed design procedures. The results of the finite element analysis (FEA) and experiments finally verify the performance of the designed stages and validate the effectiveness of the proposed design method.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105808"},"PeriodicalIF":4.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445640","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

Multiple lubricated joints with long and short bearings in multibody mechanical systems - Modeling, simulation, and performance analysis 多体机械系统中带有长短轴承的多重润滑接头 - 建模、模拟和性能分析

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-16 DOI: 10.1016/j.mechmachtheory.2024.105815

Bassam J. Alshaer , Hamid M. Lankarani

{"title":"Multiple lubricated joints with long and short bearings in multibody mechanical systems - Modeling, simulation, and performance analysis","authors":"Bassam J. Alshaer , Hamid M. Lankarani","doi":"10.1016/j.mechmachtheory.2024.105815","DOIUrl":"10.1016/j.mechmachtheory.2024.105815","url":null,"abstract":"<div><div>This study examines the effect of multiple lubricated imperfect long and short bearings on the performance of a multibody mechanical system. Unlike the typical assumption of a single perfect or imperfect lubricated joint due to modeling difficulties, this research considers the practical impacts of clearances in multiple joints. While unlubricated joints generally cause significant performance issues, lubricants reduce these effects, creating more localized peaks. The findings show that as the number of lubricated joints increases, both the magnitude and frequency of these peaks rise. In systems with multiple journal bearings, torque peaks become more noticeable due to the additional degrees of freedom introduced by the clearances. These degrees of freedom amplify acceleration, leading to higher lubricant reaction forces, which in turn require greater motor torque peaks to maintain the system's kinematics. Shorter lubricated joints exhibit more severe peaks than longer ones, mainly due to side leakage causing axial pressure variation and reduced damping capacity. The study highlights the need to replace idealized joints with imperfect ones for more accurate modeling of practical systems.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105815"},"PeriodicalIF":4.5,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441353","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 wearable robot for lower limb fracture reduction and rehabilitation: Design and experimental verification 用于下肢骨折复位和康复的可穿戴机器人：设计与实验验证

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-16 DOI: 10.1016/j.mechmachtheory.2024.105806

Zhiyuan He , Panfeng Wang , Yimin Song , Tao Sun

{"title":"A wearable robot for lower limb fracture reduction and rehabilitation: Design and experimental verification","authors":"Zhiyuan He , Panfeng Wang , Yimin Song , Tao Sun","doi":"10.1016/j.mechmachtheory.2024.105806","DOIUrl":"10.1016/j.mechmachtheory.2024.105806","url":null,"abstract":"<div><div>Most current orthopedic robots focused on fracture reduction surgery with limited involvement in postoperative rehabilitation training. However, post-surgical orthopedic rehabilitation training directly impacts the recovery of mobility, ambulation, and limb function in patients. Here, we propose a six degree-of-freedom (DoF) parallel robot that can perform fracture reduction surgery as well as postoperative rehabilitation training for lower limb. The actuation system is switchable to reduce the weight in fixed status and reuse the actuation units for lowering treatment costs. An optimal parameter design based on multi-objective optimization is presented for maintaining lightweight and high stiffness. The wearable robot has a 1.7 kg weight in electric mode and 1.3 kg in manual mode, with >80 kg payload. A hierarchical control strategy with three control modes is developed to meet the requirements of different stages of fracture treatment. Our preliminary experiments on bone models demonstrated the potential effectiveness of the proposed wearable robot for lower limb fracture reduction and rehabilitation training.</div></div>","PeriodicalId":49845,"journal":{"name":"Mechanism and Machine Theory","volume":"203 ","pages":"Article 105806"},"PeriodicalIF":4.5,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441352","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

Experimental and numerical analyses of grid couplings in quasi-static and dynamic conditions 准静态和动态条件下网格耦合的实验和数值分析

IF 4.5 1区工程技术

Mechanism and Machine Theory Pub Date : 2024-10-15 DOI: 10.1016/j.mechmachtheory.2024.105807

E. Rechreche , J. Bruyère , Q. Le Guennec , P. Velex

引用次数: 0