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To investigate the vortex-induced vibration (VIV) of a flexible cable in the uniform flow, experiments were conducted using a flexible cable with an external diameter of 80 mm and a length of 10.48 m in the wind tunnel. The characteristics of multi-modal VIV, time-frequency and traveling wave behavior of the flexible cable were analyzed. Moreover, the effects of twist direction, diameter and the single/double helical wire on the VIV characteristics of the flexible cable were investigated. It is found that the flexible cable experiences single and multi-modal VIVs in uniform flow at different incoming wind speeds, respectively. For the multi-modal VIV of the flexible cable, the vibration over the time history is dominated by two adjacent modal frequencies and shows a phenomenon of beat vibration. The multi-modal VIV responses of the flexible cable show a mix of standing and traveling wave behaviors, in which the effects of standing wave are more pronounced near both ends and the effects of traveling wave are more dominant in the middle region of the flexible cable. The twist direction of the helical wire has little effect on the VIV responses of the flexible cable. The VIV amplitudes of the flexible cable can be reduced by a single helical wire. With the diameter of the helical wire increases, the suppression effects of the single or double helical wire on the VIV of the flexible cable can be improved. Particularly, the double helical wire with diameter 0.10D can effectively suppress the VIV of the flexible cable. [ABSTRACT FROM AUTHOR]

Introduction. Cable structures belong to perspective roof systems. Specialized software packages for structural analysis, however, do not provide optimization tools for obtaining efficient design solutions of the cable structures. Thus, development of improved methods for design and analysis of cable systems is an important task to be solved. An advanced technique for flexible cable analysis is proposed. It includes ordinary operations of summing the coefficients and their products. The technique is applicable for non-commercial mathematical software packages with numerical simulation tools included, thus providing structural optimization capabilities.Materials and methods. The technique proposed is based on the sine-series expansion of the external load and the shape function of the flexible cable. The differential equation of cable equilibrium is thus transformed into the set of algebraic equations. The cable length is expressed in algebraic form by means of the power expressions for the sum of the series.Results. The equation for the flexible cable is derived. It includes cable ordinate, axial stiffness, relative elongation and the external load parameters. The technique for determination of the axial stiffness of the cable is proposed under the operability conditions. The techniques for finding load-induced vertical displacements, as well as the initial cable sag and the undeformed length are given. The length of the cable under load and the ordinate given the cable length are proposed.Conclusions. The technique for flexible cable analysis allows taking into account distributed transverse external loads. For a combined load the coefficients of the series are the sum of the particular load coefficients. The technique is intended for automated structural solution. It allows facilitating the preliminary design stage, thus providing optimal parameters determination and in-depth design study implementation. Further development of the proposed technique encompasses the fields of non-shallow cable analysis, multy-chord cable systems, cable structures with stiffening girders, strutted cable systems and spatial roof structures.

In this study, a boundary controller based on a peak detector system has been designed to reduce vibrations in the cable–tip–mass system. The control procedure is built upon a recent modification of the controller, incorporating a non-symmetric peak detector mechanism to enhance the robustness of the control design. The crucial element lies in the identification of peaks within the boundary input signal, which are then utilized to formulate the control law. Its mathematical representation relies on just two tunable parameters. Numerical experiments have been conducted to assess the performance of this novel approach, demonstrating superior efficacy compared to the boundary damper control, which has been included for comparative purposes. [ABSTRACT FROM AUTHOR]

Available computer-aided assembly process planning methods fail to provide the necessary level of accuracy required by modern complex planning processes owing to the neglect of the internal friction arising in the process of cable movement and large cable deformation conditions. The present study addresses this issue by developing a computer-aided assembly process planning method that inherently considers the tensile, bending, and torsional deformations of cables based on a dynamic viscoelastic Cosserat model describing cable motion. The simulation module of the virtual cable assembly process integrates and optimizes an efficient and robust algorithm for rapidly solving the dynamic cable model based on a semi-implicit Euler method. The performance of the proposed method is verified by demonstrating the rationality and accuracy of the assembly path planning and multi-cable assembly sequence obtained by the virtual assembly simulation module for a modeled prototype of a complex electromechanical product produced in the aerospace industry. Graphical abstract [ABSTRACT FROM AUTHOR]

In actual industrial sites, verifying the framework for cable manipulation is crucial. Therefore, it is necessary to simulate the deformation of the cable to predict its behavior accurately. By simulating the behavior in advance, it is possible to reduce the time and cost required for work. Although finite element analysis is used in various fields, the results may differ from the actual behavior depending on the method of defining the analysis model and analysis conditions. This paper aims to select appropriate indicators that can effectively cope with finite element analysis and experiments during cable winding work. We perform finite element analysis of the behavior of flexible cables and compare the analysis results with results from experiments. Despite some differences between the experimental and analysis outcomes, an indicator was developed through trial and error to align the two cases. Errors occurred during the experiments depending on the analysis and experimental conditions. To address this, weights were derived through optimization to update the cable analysis results. Additionally, deep learning was utilized to update the errors caused by material properties using the weights. This allowed for finite element analysis even when the exact physical properties of the material were unknown, ultimately improving the analysis performance. [ABSTRACT FROM AUTHOR]

In this study, a boundary controller based on a peak detector system has been designed to reduce vibrations in the cable–tip–mass system. The control procedure is built upon a recent modification of the controller, incorporating a non-symmetric peak detector mechanism to enhance the robustness of the control design. The crucial element lies in the identification of peaks within the boundary input signal, which are then utilized to formulate the control law. Its mathematical representation relies on just two tunable parameters. Numerical experiments have been conducted to assess the performance of this novel approach, demonstrating superior efficacy compared to the boundary damper control, which has been included for comparative purposes.

In this paper, a numerical model based on Euler-Bernoulli beam theory and a single van der Pol wake oscillator model is proposed to study the vortex-induced vibration of a long flexible catenary cable with a low mass ratio. The wake model uses only one oscillator to describe the in-line and cross-flow vibration with consideration of their nonlinear coupling. An experiment on a flexible cable model in perpendicular flow is carried out to validate the proposed numerical model. Numerical results and experimental measurements are compared on the vortex-induced vibration responses including the maximum amplitude, axial tension, and vibration frequency. A sensitivity analysis of the parameters used in the numerical model has been carried out. Numerical simulations by the proposed numerical model with properly selected parameters have demonstrated that the vibration frequency and the axial tension can be well predicted, and the variation of the vibration amplitudes can also be properly captured. The lock-in phenomena and the axial tension variation of the long flexible catenary cable in perpendicular flow have been carefully studied both numerically and experimentally. • Numerical and experimental studies on vortex-induced vibrations of a long flexible catenary cable are carried out. • A single wake oscillator model is applied to analyze the cable dynamic response in perpendicular flow. • The VIV Characteristics of the cable are identified. [ABSTRACT FROM AUTHOR]

In actual industrial sites, verifying the framework for cable manipulation is crucial. Therefore, it is necessary to simulate the deformation of the cable to predict its behavior accurately. By simulating the behavior in advance, it is possible to reduce the time and cost required for work. Although finite element analysis is used in various fields, the results may differ from the actual behavior depending on the method of defining the analysis model and analysis conditions. This paper aims to select appropriate indicators that can effectively cope with finite element analysis and experiments during cable winding work. We perform finite element analysis of the behavior of flexible cables and compare the analysis results with results from experiments. Despite some differences between the experimental and analysis outcomes, an indicator was developed through trial and error to align the two cases. Errors occurred during the experiments depending on the analysis and experimental conditions. To address this, weights were derived through optimization to update the cable analysis results. Additionally, deep learning was utilized to update the errors caused by material properties using the weights. This allowed for finite element analysis even when the exact physical properties of the material were unknown, ultimately improving the analysis performance.

Suspension bridges are characterized by exceptional architectural expressions and excellent technical and economic properties. However, despite all advantages, suspension bridges have a few negative features. Suspension bridges with flexible cables share excessive deformation caused by the displacement of kinematic origin. In order to increase the stiffness of suspension bridges, an innovative structural solution refers to rigid cables used instead of the flexible ones. The paper describes a methodology for calculating an asymmetric single-pylon suspension bridge with rigid cables considering installation features. Also, the article presents the numerical simulation of the bridge and determines the accuracy of the proposed methodology. First published online 15 June 2021

The purpose of this paper is to investigate friction forces in the design of a single-core flexible cable in the deformation zone and the practical applicability of the results obtained for these purposes. The power interaction of the design of a single-core flexible cable during its deformation is considered. For the first time, formulas were obtained for determining the interaction forces between the constituent parts of a single-core cable as a composite multilayer beam. A calculation technique has been developed and shear force values have been determined for some types of single-core flexible cables. The nature of the change in these forces along the length of the cable is investigated. At the beginning of the cable deformation zone, the force value can fluctuate within its constant value. In the remaining part, the shear forces along the section are constant and only at the end of the deformation zone is zero. Practically, the formulas work for the tasks. The resulting expressions for shearing forces allow one to evaluate the tribological interaction of the constituent parts of each cable element and take into account their influence when creating multicore cables. The results of the research can be used to improve the reliability of the design of flexible cables at the design stage. [ABSTRACT FROM AUTHOR]

Copyright of China Petroleum Machinery is the property of China Petroleum Machinery Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper considers certain issues of tribological interaction between flexible cable elements. It proposes a new approach for determining frictional forces of cable elements while taking into account cable parameters. This study is the first to derive formulas of mechanical stresses in the zone of contacting elements for assessing the cable strength. The paper demonstrates how the derived formulas for cables can be used in practice for design purposes. The influence of geometric parameters of cable design on its strength has been analyzed. [ABSTRACT FROM AUTHOR]

Highlights • The first, second and third mode VIVs of a flexible cable model are reproduced and the frequency lock-in phenomenon is observed for different modes of VIVs. • It is feasible to reproduce multi-mode RWIVs of a flexible cable in a wind tunnel. • Water rivulets on the cable surface excite RWIVs, and higher-mode RWIVs develop at higher wind speeds. • Local distributions of upper rivulet water flow excite multi-mode RWIVs. • RWIVs and VIVs may have causal links. Abstract We reproduce multi-modal vortex-induced vibrations (VIVs) and multi-modal rain–wind-induced vibrations (RWIVs) of an inclined and yawed cable in wind tunnel tests. The flexible cable model has low mass and low damping. First, the cable model is kept dry and exposed to uniform airflow; it experiences first-, second- and third-mode VIVs with the increase of wind speed. The structural responses of VIVs are analysed and the frequency lock-in phenomenon is observed for different modes of VIVs of the flexible cable. In addition to VIVs of the dry cable, RWIVs are excited by guiding water rivulets on the cable surface from a water tube. The first-, second- and third-mode RWIVs of the flexible cable are observed and identified at a much higher range of incoming wind speeds than that of the VIVs. To further explore the origin of the multi-modal behaviours of RWIVs, the upper rivulet is guided and restricted to form locally along the cable. Experimental results reveal that the higher- and multiple-mode RWIVs can be excited by a local rivulet, even under a lower wind speed. Finally, RWIVs are compared to VIVs to uncover their underlying similarities and relationships. [ABSTRACT FROM AUTHOR]

The friction and wear of flexible cables are the main factors that cause electrical breakdown and insulation aging, and they greatly reduce the reliability and safety of robots. In order to enhance the reliability and safety of the robot, it is of great necessity to investigate the friction and wear mechanisms of the flexible cable. In this research, the friction and wear mechanisms have been discussed. The effects of relative speed, ambient temperature, and positive pressure on the flexible cables are considered by an orthogonal frictional movement. The cable friction force has been measured by a piezoelectric sensor with high natural frequency characteristics. The relations among friction and different factors affecting friction have also been discussed. The results show that the relative speed and the ambient temperature are the main factors affecting the friction and wear of the cable; the main form of flexible cable wear is mechanical-force chemical friction and wear. Those discoveries will greatly deepen the understanding of the friction and wear mechanisms of flexible cables, and will be beneficial to robot cable-reliability design.

This paper reports a novel assembly method for 3-dimensional (3D) microelectrode array with the aid of anisotropic conductive film (ACF). For this purpose, a unique silicon probe with trenches encircled bonding pads was fabricated to realize the ACF-bonding with flexible cable. This design is meaningful because it can realize planar bonding for subsequently convenient 3D stacking and the time-consuming plating is not needed to form bumping on pads. The reliability of the ACF-bonding is demonstrated by measuring the electrochemical impedance spectra (EIS) of the bonded probes with different structural and dimensional bonding pads. The bonded probes are further assembled into 3D arrays and integrated with micro-drive for chronic neural recordings. The excellent recording performance indicates that the ACF-bonded probes are reliable and suitable for chronic neural recordings. [ABSTRACT FROM AUTHOR]

Remanufacturing cleaning plays an important role in the remanufacturing process. It has a significant influence on the residual life detection and remanufactured products quality. But it is the most polluted and time-consuming phase in the remanufacturing process. In this paper a simple, efficiency and low pollution cleaning method is introduced. This method is based on Hertz and Coulomb theory with flexible cable impact contact and friction, without introducing new pollution medium in the process. In order to study the method in detail, the working mechanism, the kinematic and dynamic characteristics are analyzed. Simulation and application test are carried out on the steel plate and get a good cleaning effect. [ABSTRACT FROM AUTHOR]

The assembly simulation of flexible cable based on physical modelling is a key link in virtual product design. However, due to the complicated large deformation of the flexible cable, there are two problems in the physical simulation model: one is that it is too difficult to carry out three-dimensional comparison validation between the simulation model and the real model, the other is that the render time of the simulation model is too long. Aiming at these two problems, a flexible cable geometry measurement and rapid modelling method based on noncontact 3D laser scanning technology is proposed. Targeting at the large deformation characteristics of flexible cable, this method establishes the activity testbed for two-end clamped cable, and point cloud data reflecting the cable geometry under different boundary conditions are gained with the help of a 3D laser scanner with coordinate measuring arms. Furthermore, the central axis of the cable is extracted on the basis of the point cloud data segmentation idea and the active contour model, and rapid geometry modelling and expression for flexible cable is realized based on the idea of sphere-moving surface. Finally, the cable geometry simulation system is developed based on an open source geometric kernel system, and the relevant models and algorithms are validated effectively. [ABSTRACT FROM AUTHOR]

The dynamic analysis of cable-pulley systems is investigated in this paper, where the time-varying length characteristic of the cable as well as the coupling motion between the cable and the pulleys are considered. The dynamic model for cable-pulley systems are presented based on the principle of virtual power. Firstly, the cubic spline interpolation is adopted for modeling the flexible cable elements and the virtual 1powers of tensile strain, inertia and gravity forces on the cable are formulated. Then, the coupled motions between the cable and the movable or fixed pulley are described by the input and output contact points, based on the no-slip assumption and the spatial description. The virtual powers of inertia, gravity and applied forces on the contact segment of the cable, the movable and fixed pulleys are formulated. In particular, the internal node degrees of freedom of spline cable elements are reduced, which results in that only the independent description parameters of the nodes connected to the pulleys are included in the final governing dynamic equations. At last, two cable-pulley lifting mechanisms are considered as demonstrative application examples where the vibration of the lifting process is investigated. The comparison with ADAMS models is given to prove the validity of the proposed method. [ABSTRACT FROM AUTHOR]

The crossing obstacle distance of three type dual-arms inspection robots， including arms fixed robot， arms mobile robot and robot with flexible cable， was investigated. The mathematical models were established for the crossing obstacle distance of the three type dual-arms inspection robots by theoretical analysis. Under similar values of the quality and dimensions， the max crossing obstacle distance of the three type robots were calculated based on the different gradients of the transmission line. The results show that the arm movements of dual-arms inspection robot with flexible cable are more flexible with a larger crossing obstacle distance， which can be regulated by the obstacle size. Thus， the dual-arms inspection robot with flexible cable has obvious advantages in realizing lightweight structure design. [ABSTRACT FROM AUTHOR]

Copyright of Journal Européen des Systèmes Automatisés is the property of International Information & Engineering Technology Association (IIETA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flexible cables play significant role in the field of intelligent production and manufacturing. However, with prolonged use, wear will inevitably occur, threatening the safety of operators. And the high temperature of the working will accelerate wear. Hence, the effect of the high temperature was investigated in wear performance of flexible cable. The friction and wear evolution at high temperatures were studied combining the tension stress and elongation. The results show the interaction of heat and wear affects cable friction. At high temperature maximum frictional force increases by 68.93 % compare to the lowest friction at low temperature; the wear is accelerated maximum 90 %. The minimal tensile stress and the elongation at break of cable appear at 1.5 h, which is consistent with the friction force and wear results. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the existing bypass operation system, need many vehicles, in the meantime it's mobility was poor and it's safety protection was difficult, 10 kV distribution network bypass work platform was developed and manufactured. Meanwhile, the influence of insulation protection, safe distance and the control strategy were considered comprehensively, a small bypass operation method based on the 10 kV bypass work platform was proposed. The electric field intensity of the bypass cables was calculated by the finite element method. The field test demonstrated the effectiveness of the method. The results show that the method is safe, convenient and reliable owing to integrating the bypass load switch and flexible cable on the mobile work platform. [ABSTRACT FROM AUTHOR]