Cable Model Research Articles

Identification and Localization Study of Grounding System Defects in Cross-Bonded Cables

Cross-bonded cables improve transmission efficiency by optimizing the grounding method. However, due to the complexity of their grounding system, they are prone to multiple types of defects, making defect state identification more challenging. Additionally, accurately locating sheath damage defects becomes more difficult in cases of high transition resistance. To address these issues, this paper constructs a distributed parameter circuit model for cross-bonded cables and proposes a particle swarm optimization support vector machine (PSO-SVM) defect classification model based on the sheath voltage and current phase angle and amplitude characteristics. This model effectively classifies 25 types of grounding system states. Furthermore, for two types of defects—open joints and sheath damage short circuits—this paper proposes an accurate segment-based location method based on fault impedance characteristics, using zero-crossing problems to achieve efficient localization. The results show that the distributed parameter circuit model for cross-bonded cables is feasible for simulating electrical quantities, as confirmed by both simulation and real-world applications. The defect classification model achieves an accuracy of over 97%. Under low transition resistance, the defect localization accuracy exceeds 95.4%, and the localization performance is significantly improved under high transition resistance. Additionally, the defect localization method is more sensitive to variations in cable segment length and grounding resistance impedance but less affected by fluctuations in core voltage and current.

Prediction of mechanical characteristics of shearer intelligent cables under bending conditions.

The frequent bending of shearer cables during operation often leads to mechanical fatigue, posing risks to equipment safety. Accurately predicting the mechanical properties of these cables under bending conditions is crucial for improving the reliability and service life of shearers. This paper proposes a shearer optical fiber cable mechanical characteristics prediction model based on Temporal Convolutional Network (TCN), Bidirectional Long Short-Term Memory (BiLSTM), and Squeeze-and-Excitation Attention (SEAttention), referred to as the TCN-BiLSTM-SEAttention model. This method leverages TCN's causal and dilated convolution operations to capture long-term sequential features, BiLSTM's bidirectional information processing to ensure the completeness of sequence information, and the SEAttention mechanism to assign adaptive weights to features, effectively enhancing the focus on key features. The model's performance is validated through comparisons with multiple other models, and the contributions of input features to the model's predictions are quantified using Shapley Additive Explanations (SHAP). By learning the stress variation patterns between the optical fiber, power conductor, and control conductor in the shearer cable, the model enables accurate prediction of the stress in other cable conductors based on optical fiber stress data. Experiments were conducted using a shearer optical fiber cable bending simulation dataset with traction speeds of 6 m/min, 8 m/min, and 10 m/min. The results show that, compared to other predictive models, the proposed model achieves reductions in Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE) to 0.0002, 0.0159, and 0.0126, respectively, with the coefficient of determination (R2) increasing to 0.981. The maximum deviation between predicted and actual values is only 0.86%, demonstrating outstanding prediction accuracy. SHAP feature analysis reveals that the control conductor features have the most substantial influence on predictions, with a SHAP value of 0.095. The research shows that the TCN-BiLSTM-SEAttention model demonstrates outstanding predictive capability under complex operating conditions, providing a novel approach for improving cable management and equipment safety through optical fiber monitoring technology in the intelligent development of coal mines, highlighting the potential of deep learning in complex mechanical predictions.

Simulation and Stability Analysis of a Coupled Parachute–Payload System

High-fidelity simulations are used to study the stability of a coupled parachute–payload system in different configurations. A 8.53 m ring–slot canopy is attached to two separate International Organization for Standardization (ISO) container payloads representing a Twenty Foot Equivalent (TEU). To minimize risk and as an alternative to a relatively expensive traditional test program, a multi-phase design and evaluation program using computational tools validated for uncoupled parachute system components was completed. The interaction of the payload wake suspended at different locations and orientations below the parachute were investigated to determine stability characteristics for both subsonic and supersonic freestream conditions. The DoD High-Performance Computing Modernization Program CREATETM-AV Kestrel suite was used to perform CFD and fluid–structure interaction (FSI) simulations using both delayed detached-eddy simulations (DDES) and implicit Large Eddy Simulations (iLES). After analyzing the subsonic test cases, the simulations were used to predict the coupled system’s response to the supersonic flow field during descent from a high-altitude deployment, with specific focus on the effect of the payload wake on the parachute bow shock. The FSI simulations included structural cable element modeling but did not include aerodynamic modeling of the suspension lines or suspension harness. The simulations accurately captured the turbulent wake of the payload, its coupling to the parachute, and the shock interactions. Findings from these simulations are presented in terms of code validation, system stability, and drag performance during descent.

Cable Force Distribution and Motion Control for a Cable-Driven Super-Redundant Robot Under Stiffness Constraints

Abstract Cable-driven super-redundant robots (CDSSR) with slender and flexible bodies have wide application potential in narrow spaces. However, the control accuracy of the robot is affected by the instability of the operating stiffness during motion, which is related to the diversity of the cable tension distribution solutions. To solve this problem, an analytical stiffness model of the cable-driven super-redundant robot is first constructed based on the virtual work principle. Then, an optimal cable tension distribution model based on energy optimization and stiffness constraint is proposed. Third, a motion control framework of cable-driven super-redundant robot with stiffness constraints is proposed. Finally, constant stiffness control experiments and repeated positioning accuracy experiments of robot end under different end stiffness conditions are carried out on a 21-DOF cable-driven super-redundant robot. The results show that the proposed control strategy can achieve constant stiffness control. When the stiffness of the robot is adjusted from 200 N/m to 300 N/m, the repeated positioning accuracy in the X, Y, and Z directions is increased by 40.00%, 27.62%, and 53.09%, respectively. When the end stiffness is adjusted from 300 N/m to 400 N/m, the repeated positioning accuracy in the X, Y, and Z directions is increased by 40.81%, 58.08%, and 64.99%, respectively. The experimental results show that the proposed cable force distribution model and control strategy are effective.

Numerical simulation of fracture evolution behaviors in deep roadway surrounding rock containing discontinuous joints

To explore the internal bearing characteristics and fracture evolution laws of discontinuous jointed rock mass in deep roadways, the −600 m main roadway in Xin ’an Coal Mine was used as the research background. The fracture fractal dimension D was employed to characterize the joint density, and an intermittent jointed roadway model, both without support and with anchor cable support, was modeled using the particle flow software PFC2D. The internal stress, deformation, and fracture characteristics of intermittent jointed surrounding rock in tunnels with different support methods and joint densities were studied from a microscopic perspective. The results indicate that during the bearing process of the bolt anchor support and unsupported roadway discontinuous jointed rock mass model, the main bearing area of both models transferred from the surface rock mass to the deep rock mass. The tensile cracks of the anchor cable support model were reduced by 57.7% compared with the unsupported model, effectively suppressed the tensile failure of the surrounding rock, and the convergence of the surrounding rock was substantially reduced. The density of intermittent joints was negatively correlated with the bearing capacity of the surrounding rock mass of roadways, and the increase of joint density the overall failure of the surrounding rock, and the possibility of roadway destabilization was increased. Importantly, the number and distribution of intermittent joints in the surface surrounding rock were closely related to the rupture characteristics of the roadways. When the load exceeded the ultimate load of the deep surrounding rock, stress fluctuation occurred due to the stress drop caused by its destruction. This fluctuation promoted the development of intermittent joints in the surface surrounding rock, increasing the risk of roadway destabilization.

Dynamic Modeling and Analysis on the Cable Effect of USV/UUV System Under High-Speed Condition

This paper investigates the stability issues of the Unmanned Surface Vehicle (USV)–Unmanned Underwater Vehicle (ROV) system induced by cable loads under real marine conditions and high-speed operation. This study focuses on the dynamic coupling characteristics of cable forces affecting the unmanned platform and outlines the variation patterns of these forces under different operational scenarios. By developing the dynamic models of the USV, UC, and UUV, a comprehensive system model for the unmanned marine platform is constructed. The accuracy of the cable model is validated through experimental results, and the coupling interference effects of the cable during collaborative operations are systematically analyzed from multiple perspectives. Additionally, the cable tension and force behaviors under high-speed cruising conditions are thoroughly examined. The results provide a solid foundation for the development of cable load prediction models for collaborative marine unmanned platforms, and offer both theoretical and numerical insights for dynamic control strategies based on cable force adjustments.

Performance Analysis of NR-DCSK Based Copper Cable Model for G.fast Communication

Performance Analysis of NR-DCSK Based Copper Cable Model for G.fast Communication

Internal flow effect of a flexible riser system for a floating offshore wind turbine with on-board carbon dioxide capture

This paper designs a flexible riser for transporting carbon dioxide (CO2) off a floating offshore wind turbine (FOWT)-powered CO2 capture platform, and analyzes the internal flow-induced effects caused by the CO2 on the flexible riser. Internal effects on flexible risers due to the pressurized and internal dynamic flow are a well-studied problem in offshore oil and gas (O&G) applications, which typically requires the use of tools capable of representing their pressurized contents and flows. However, because the flow rates and pressure conditions expected from individual FOWT-CO2 capture platforms are much lower than those used in O&G installations, we studied the importance of internal flow effects on riser dynamics. To determine their relevance, we designed and modelled the flexible riser in OrcaFlex™ with different design pressure and flow conditions under normal and extreme environmental events. The results indicate that the riser’s effective tension and curvature are not significantly affected by internal flow effects, but differences were observed in the von Mises stress arising from the shear stress, which is a purely hydrostatic term. As such, as long as the shear term is properly accounted for, these results enable future work to utilize simplified models for the flexible riser system, similar to models for dynamic power cables employed in FOWT farms. This simplification allows us to design and analyze the whole FOWT-CO2 system alternatively with lower fidelity and open-source offshore wind turbine simulation tools, like OpenFAST, without overlooking relevant riser-dynamics phenomena.

Camera-based control system of a planar cable-driven parallel robot intended for functional rehabilitation

Abstract This paper investigates a closed-loop visual servo control scheme for controlling the position of a fully constrained cable-driven parallel robot (CDPR) designed for functional rehabilitation tasks. The control system incorporates real-time position correction using an Intel RealSense camera. Our CDPR features four cables exiting from pulleys, driven by AC servomotors, to move the moving platform (MP). The focus of this work is the development of a control scheme for a closed-loop visual servoing system utilizing depth/RGB images. The developed algorithm uses this data to determine the actual Cartesian position of the MP, which is then compared to the desired position to calculate the required Cartesian displacement. This displacement is fed into the inverse kinematic model to generate the servomotor commands. Three types of trajectories (circular, square, and triangular) are used to test the controller’s compliance with its position. Compared to the open-loop control of the robot, the new control system increases positional accuracy and effectively handles cable behavior, various perturbations, and modeling errors. The obtained results showed significant improvements in control performance, notably reduced root mean square error and maximal error in terms of position.

Dynamic response and fatigue damage of catenary mooring cables based on ANCF

Based on the absolute nodal coordinate formulation (ANCF), this paper develops a numerical model for computing the dynamics and fatigue damage of catenary mooring cables. The catenary mooring cable is modeled using ANCF elements, with hydrodynamic loads incorporated through the Morison equation and seabed reaction forces simulated by spring-based seabed resistance. After validating the ANCF mooring cable model through a comparison with Orcaflex, the effects of incident flow direction and various excitations on the dynamic characteristics and fatigue damage of the mooring cable are discussed. Subsequently, the validation results of the ANCF mooring cable model are compared with those from MoorDyn, further highlighting the model’s effectiveness and practicality in engineering applications. Subsequently, by varying the mooring line length, the dynamic characteristics under different length conditions are analyzed, and fatigue damage is evaluated. The study reveals the impact of incident flow direction and mooring line length on the dynamic characteristics and fatigue damage. It is found that shortening the mooring line significantly enhances the constraints on the SPAR platform and affects the fatigue damage of the mooring line. Effective mitigation of fatigue damage can be achieved by avoiding the most unfavorable incident flow direction or adjusting the length of the mooring line.

Optimized design and testing of a multi-degree-of-freedom cable-driven underactuated picking manipulator

In order to address the issues of poor flexibility and complex control systems in existing picking manipulators, the present work designs a multi-degree-of-freedom cable-driven underactuated manipulator. Firstly, an end-effector drive module based on the cam mechanism is designed, which can control gripping force without the need for force sensor feedback, and enables the opening, closing, and rotary movements of the end-effector to be controlled by the same motor. Secondly, the influence of the structural parameters of the fingers on the contact force at the phalange is analyzed, and then the end-effector is optimized using a genetic algorithm. Next, the cable pulling force control model is established. Subsequently, a prototype manipulator is fabricated for testing, the results show that the adjustment range of cable pulling force is 11.1–27.4 N, and the output torque of manipulator is 0.64 N·m. Finally, the results of picking test in the orchard demonstrate that the manipulator is capable of accomplishing non-destructive picking operations.

Key structure and technology of bridge cable maintenance robot – a review

Purpose The cable inspection robot is essential in maintaining bridge cables. The purpose of this paper is to summarize the maintenance methods of bridge cables. It summarizes the advantages and disadvantages of the critical structures of the external overall frame, intermediate adhesion device, attachment mechanism and driving method of the cable inspection robot. Finally, it discusses the challenges the cable inspection robot faces and the direction of future research. Design/methodology/approach This paper summarizes the research progress of the cable inspection robot and details the advantages and disadvantages of critical structures such as the external frame, intermediate adhesion device, attachment mechanism, driving method and safe return device of the robot. Finally, it points out the future direction of cable inspection robots, including lightweight design, hybrid design, multi-robot cooperative work, multi-technology integration and intelligent cable inspection digital twin model. Findings The cables are the main load-bearing components of a bridge, and their safety is crucial. However, subjected to varying loads and environmental influences over a long period, cables are prone to damage, threatening the bridge’s stability. Cable inspection robots can comprehensively detect and repair cable damage, significantly improving efficiency and safety. Originality/value This paper provides a comprehensive review of the current research on cable inspection robots, enabling readers to have a comprehensive and systematic understanding of the critical structures and key technologies of cable inspection robots and providing scientific references for researchers working on cable inspection robots.

Vision-based experimental study of force estimation in the cable-stayed bridge’s cable model

In this paper, a vision-based measurement is proposed, so as to realize quick and convenient tests on the cable force of single-cable plane cable-stayed bridge. Firstly, laser is used to lay out the reference points, and pictures are taken by mobile phone or camera, gaining cable sag by serial image processing. The next step is to calculate the cable force by its relation with sag. According to laboratory test of cable force, the measuring error of cable force is within 3%, which meets the engineering precision requirements. This simple, efficient and low-risk method is easy to operate, and can solve the difficulty of marker installation during visual measurement.

Simulation of High-Voltage Cable Sheath Current with a Panoramic Digital Tunnel Model

Monitoring cable sheath current is crucial for guaranteeing the secure and efficient operation of high-voltage cable tunnels. In this study, a three-dimensional (3D) panoramic digital model of a tunnel in Beijing is modeled, a parallel cable sheath current simulation model is proposed, and a 3D panoramic visualization system with which the cable sheath current can be simulated online is developed in order to generate early warnings on the sheath current situation. The accuracy of the simulation model is verified and the results are as follows: The difference between the simulated sheath current and the actual measurement is within a maximum margin of 3.71%. A phase sequence optimization strategy can be obtained after calculations based on the simulation model, and an average sheath current reduction of 47.2% can be achieved following the optimization strategy. This study introduces a new approach by which cable sheath current dynamics and real-time warning against anomalies are visualized on a 3D tunnel model. In addition, a sheath current simulation model is integrated in the 3D visualization system developed in this study, and phase sequence optimization strategies for cables with abnormal sheath currents are automatically suggested, which may provide scientific support for auxiliary decision-making in real-time cable operation.

A Modified Bearing Capacity Model for Inclined Shallow Anchor Cable with Experimental Verification

Most theoretical models of shallow anchor cables do not take the effect of anchor inclination into consideration, which is an important factor influencing load distribution, stress concentration, and failure mechanisms. In this paper, a modified bearing capacity was developed for a single anchor cable, taking the anchor inclination into consideration, based on the principle of limit equilibrium. Then, a series of indoor pull-out tests of single anchors with different inclinations were performed, where the effects of the anchor inclination on the bearing capacity and failure mechanisms were carefully analyzed. The experimental bearing capacities were compared to the predicted data of the proposed modified model, as well as other existing experimental results, aiming to verify the applicability and accuracy. The results show that the bearing capacity increases with decreasing anchor inclination because the vertical component of the force acting on the anchor cable increases. The failure models of the anchor cables, pulled out at different angles, exhibit an asymmetric “inverted trumpet” shape, which is caused by the varying stress distributions around the anchor cable during pull-out. In addition, the bearing capacities of the theory differ very little from the experimental and previous results, with a max error of nearly 10%. This study confirms that the proposed model reliably captures the effects of anchor inclination, providing valuable insights for designing inclined anchors in engineering practice.

Research on Digital Prototype Model Design of Missile Electrical System

Abstract The design of missile electrical systems involves various aspects such as electrical network, wiring harness connection relationships, wiring harness layout, and electromagnetic compatibility design. Traditional design methods cannot meet the design requirements of missile electrical systems due to many drawbacks. In this paper, a method to design digital prototype model is proposed. The digital prototype model consists of two parts: the design of cable electrical model is based on Capital and the design of cable structure model is based on NX. And the Digital Prototype model is archived by linking these two parts, which provides a guidance for cable manufacturing and production and laying a good foundation for future research.

Multiscale finite element modelling of dynamic subsea power cables in bending

Abstract This paper proposes a multiscale finite element modelling strategy for dynamic offshore power cables which allows for detailed analysis of individual components. The challenge of modelling the intricate power cores within the cable is addressed by considering a separate repeated unit cell (RUC) of the power core to define its stiffness, where the power cores themselves are then discretised with beam elements in the dynamic cable model. Periodic boundary conditions allowing for geometric non-linearity are employed at both the power core and dynamic cable scale. This means the model size can be reduced to the smallest possible RUC while still permitting non-linear material behaviour. The resulting model is capable of detailed stress analysis of individual components required for fatigue life estimation. The model is validated against existing experimental data showing strong agreement. The proposed multiscale approach may therefore be used to augment existing fatigue analysis methods for dynamic offshore cables where the stress state at individual wires is required.

Experimental study on the aerodynamic force and vibration of a scratched stay cable perpendicular to the wind

The wind load and wind-induced vibration of stay cables, as the primary load-bearing component in cable-stayed bridges, are highly important. Inevitably, cables experience scratches during production, transportation, and installation. Scratches may have an important effect on a cable's aerodynamic force and wind-induced vibration. Consequently, three sectional cable models with varying scratches were prepared for wind tunnel tests. The incoming wind was perpendicular to the cable model. The aerodynamic and vibration responses in precritical, critical Reynolds number regions were investigated. The results showed that scratched cables exhibit Reynolds number effects similar to those of smooth cables. Within attack angles ranging from 50° to 85°, scratching significantly reduced the corresponding Reynolds numbers of the TrBL0-1 and TrBL1-2 transitions. This caused the scratched cable to vibrate substantially at a lower Reynolds number (wind speed) than the smooth cable. There is a smaller attack angle range between 50° and 90° in which scratches cause the average lift coefficient to climb slowly with the Reynolds number, without a bistable phenomenon. This implies that there is no significant vibration. The critical Reynolds number effect effectively predicts the vibration of the scratched cable, and the complex flow in the critical Reynolds number region limits the accuracy of the Den Hartog criterion.

Underground XLPE coaxial cable length calculation and fault detection based on broadband impedance spectroscopy

Abstract Accurately determining the tested cable’s total length is important in cable fault detection and localization. Therefore, an iterative method of relative propagation coefficients based on broadband impedance spectroscopy is proposed to solve the actual length of the cable and a phase difference integral transform method for fault detection. First, the overall detection process framework is designed. Then, the cable distribution parameter model and the characteristics of the input impedance spectroscopy are analyzed. The calculation methods for determining the cable length and propagation coefficients are explained, followed by a demonstration of the fault localization process. Finally, the model LCR1000A impedance analyzer is used to measure cable length and actual faults in cables with lengths of 35 m, 100 m, and 500 m. The final fault location error is less than 0.67%, proving that the method can calculate the length of cables and various fault point locations.

Steady-State Temperature Prediction for Cluster-Laid Tunnel Cables Based on Self-Modeling in Natural Convection

Accurate temperature prediction of the operating tunnel cable is crucial for its safe and efficient function. To achieve a rapid and accurate prediction of the steady-state temperature of the tunnel cable, the self-modeling pattern in natural convection on the cable surface in the rectangular tunnel is investigated, and the self-modeling method for the convective heat transfer coefficient calculation is proposed. A thermal circuit model for single cables is further established to predict the cable core temperature, and the model is extended to predict the cluster-laid cable core temperature based on the combined method. The results show that when the tunnel size is neglected, the maximum relative deviation of the convective heat transfer coefficient between the self-modeling method and the finite element simulation is only 1.78% in the studied cases, indicating that the natural convection on the cable surface approximately satisfies the self-modeling method. Additionally, applying the self-modeling method to the thermal circuit can accurately predict the temperature of the single cable core. Furthermore, for the three-phase four-circuit cable, the maximum deviation between the temperature prediction results and the finite element results is within 2 K in the studied cases, which verifies the predictive accuracy of the combined method for the cluster-laid tunnel cable.