Pair Cables Research Articles

Transmission Line Modeling and Crosstalk Analysis of Multibraided Shielded TWP/Twinax Cables

In this article, the transmission line model of multibraided shielded cables is improved by including the proximity effect in the shield model. This is performed by deriving the analytical expressions of the transfer impedance and admittance of a shielded structure with nonuniform current distribution around the shield surfaces. After that, the formulations are generalized to be applicable for shielded twisted-wire pair (TWP) and twinax cables with line apertures and braided structure with nonuniform shield current. It is found that the nonuniform distribution of the currents in the outer and inner shield surfaces have high effects on the inner induced common-mode and differential-mode currents of braided shielded cables. In addition, the crosstalk between multishielded TWP and twinax cables is investigated in detail, indicating that the proximity effects between the shields have a critical impact on generating the crosstalk between the shielded cables. The proposed model is validated with the commercial software FEKO and excellent agreements are achieved.

Experimental Demonstration of Multigigabit Data Communication Using Surface Waves on Twisted-Pair Cables

The demand for higher broadband speeds is ever increasing whereas the deployment of full fibre to the premises is slower than initially predicted and remains costly. Solutions exploiting the existing, ubiquitous, copper network and increasing its capacity would be highly beneficial in the near term. One approach is to use surface wave (SW) transmission mode to transmit signals over the existing copper cabling network. We present proof-of-concept experimental SW data transmission on twisted pair cables. A surface wave launcher for low GHz carrier frequency operation is designed and optimised. Experimentally, we demonstrate data rates in excess of 12 Gb/s in a 1.15-3.25 GHz band over a 6.1 m twisted pair cable with an average bit error rate of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.25 \times 10 ^{-5}$ </tex-math></inline-formula> , without coding or feedback implementation. Furthermore, higher frequency bands are tested with data rates up to 3.4 Gb/s displaying their potential for surface wave transmission. S-parameter measurements allow capacity estimations of SW data transmission on longer cable lengths using water-filling algorithms. Our calculations predict over 13 Gb/s capacity on a 100 m cable using a 3.5 GHz transmission bandwidth, this may be further extended by further increases to the bandwidth used for SW transmission.

Precise Cable-Suspended Pick-and-Place with an Aerial Multi-robot System

This work introduces the G-Fly-Crane, a proof-of-concept aerial multi-robot system designed to demonstrate the advantage of using multiple aerial robots as a valuable tool for novel construction techniques, not requiring the use of heavy engines and costly infrastructures. We experimentally demonstrate its capability to perform pick-and-place and manipulation tasks in a construction scenario, with an increased payload capacity and dexterity compared to the single robot case. The system is composed of three aerial robots connected to a platform by three pairs of cables. The platform is equipped with a gripper, enabling the grasping of objects. The paper describes in detail the hardware and software architecture of our prototype and explains the implemented control methods. A shared control strategy incorporates the human operator in the control loop, thus increasing the overall system reliability when performing complex tasks. The paper also discusses the next steps required to bring this technology from indoor laboratory conditions to real-world applications.

Simulation of High Frequency Twisted Pair Cable Using DDM-FEM Hybrid Algorithm

In this article, an efficient domain decomposition method finite element method (DDM-FEM) algorithm is presented for the lossy twisted pair cable. In harsh environment and anti-interface ability, cables need high toughness, noise immunity, and extraordinary strength. We, in this paper, simulate a physical model of twisted pair cable and apply a hybrid solver of DDM-FEM to analyze these problems by compression and approximation of matrix-vector product. The DDM-FEM solver along with matrix compression is used to compute the RLCG, propagation constant in the twisted pair cable, and to reduce the computational time and memory size. Therefore, in the proposed algorithm, the complexities of the system become linear. The study compares the calculated results with the existing standard to verify the effectiveness of the proposed algorithm.

Multi-objective optimization for cost-effective aseismic design of submerged floating tunnels considering weighted preferences

In aseismic design of the submerged floating tunnel (SFT), both the seismic response and construction cost should be considered and optimized to achieve a balance between structural safety and project investment. To realize the simultaneous optimization of several design objectives, this study proposes a multi-objective-optimization-based framework for the cost-effective aseismic design of the SFT. Firstly, two design objectives, i.e., the transverse peak displacement (TPD) and the material cost (MC), are identified as the optimization objectives; The tube wall thickness, inclined angle of cables, and number of cable pairs are determined as the decision variables. Then the objective functions and constraint conditions are derived, and the nondominated sorting genetic algorithm-II (NSGA-II) is used to obtain the Pareto front and Pareto-optimal solution set. Considering the weighted preferences, a decision-making approach based on Tchebycheff's objective weight is developed to select the final optimal design scheme. The validity of the proposed approach is verified through a case study. The results imply that the optimal solution selected by the proposed approach is much superior in both TPD and MC compared with the original design scheme. Furthermore, compared with compromising programming, the proposed decision-making approach can emphasize more on TPD, which will gain more preferences from the designers.

Workspace analysis and optimal design of dual cable-suspended robots for construction

Given their advantages of large workspaces and high payload-to-weight ratios, cable-driven parallel mechanisms have great potential for use in on-site autonomous construction. This paper proposes a configuration containing two cable-suspended robots driven by eight cable pairs (four cable pairs each), which form parallelograms, to perform construction efficiently in terms of time and space. A core issue of this system is the collision problems that occur in dynamic construction processes. The use of the distance between two spatial line segments is proposed to calculate collision detection, and the wrench-feasible workspace is examined to analyze the collision-free buildable workplace. The operation mode of dual cable-suspended robots for construction is discussed herein. Further, the design variables of the dual cable-suspended robot are optimized using multi-objective particle swarm algorithm to ensure a sufficiently large collision-free buildable workspace with suitable scale and payload of the frame of the cable robots for construction.

Restoring Hand Functions in People with Tetraplegia through Multi-Contact, Fascicular, and Auto-Pilot Stimulation: A Proof-of-Concept Demonstration.

Two multi-contact epineural electrodes were placed around radial and median nerves of two subjects with high tetraplegia C4, American Spinal Injury Association Impairment Scale (AIS) A, group 0 of the International Classification for Surgery of the Hand in Tetraplegia. The purpose was to study the safety and capability of these electrodes to generate synergistic motor activation and functional movements and to test control interfaces that allow subjects to trigger pre-programmed stimulation sequences. The device consists of a pair of neural cuff electrodes and percutaneous cables with two extracorporeal connection cables inserted during a surgical procedure and maintained for 28 days. Continuity tests of the electrodes, selectivity of movements induced, motor capacities for grasping and gripping, conformity of the control order, tolerance, and acceptability were assessed. Neither of the two participants showed general and local comorbidity. Acceptability was optimal. None of the stimulation configurations generated contradictory movements. The success rate in task execution by the electro-stimulated hand exceeded the target of 50% (54% and 51% for patients 1 and 2, respectively). The compliance rate of the control orders in both patients was >90% using motion inertial measurement unit (IMU)-based detection and 100% using electromyography (EMG)-based detection in patient 1. These results support the relevance of neural stimulation of the tetraplegic upper limb with a more selective approach, using multi-contact epineural electrodes with nine and six contact points for the median and radial nerve respectively.

Analysis of Differential-Mode Signal Emission From STP Cable by Using Chain Parameter Matrix

Radiated emission from a differential-mode (DM) signal was calculated by using a chain parameter matrix for a shielded twisted pair (STP) cable. The series connection of the matrix represented the multiconductor transmission line inside the shield, and the common-mode current generated from the DM signal was obtained by solving the matrix equation. The matrix elements of the STP cable and the shield&#x0027;s transfer impedance were determined through both measurement and calculation, and these values were used to calculate the current outside the shield and the radiated electric field strength. The maximum current outside the shield and the maximum radiated electric field strength were then measured in the frequency range from 30 to 300 MHz, and these results were compared with the calculated values. The calculation results for the maximum current intensity agreed well with the measured values, and those for the maximum radiated electric field strength agreed fairly well with the measured values.

Electric Vehicle Control System by using Controller Area Network Communication

The Controller Area Network (CAN) communication protocol is designed by Bosch in the 1980s as a doubled wired, differential voltage-based serial communication system for control systems. Electric vehicles, like Gasoline vehicles, require controllers to regulate load operation, where conventional point-to-point communication system gets outcome of huge number of cables in the harness. CAN is used to minimize the amount of cables and enable various controllers to transfer data and accomplish complicated jobs simultaneously. This paper presents the design of a CAN-based control system to be used as a replacement for the existing system and shows the development of four modules as well as a proposed implementation for the complete system. Individual modules will be developed initially and later interfaced to the CAN network with CAN controller modules. All modules are connected with a twisted pair of cables for data transmission with CAN.

Electric Field and Temperature Simulations of High-Voltage Direct Current Cables Considering the Soil Environment

For long distance electric power transport, high-voltage direct current (HVDC) cable systems are a commonly used solution. Space charges accumulate in the HVDC cable insulations due to the applied voltage and the nonlinear electric conductivity of the insulation material. The resulting electric field depends on the material parameters of the surrounding soil environment that may differ locally and have an influence on the temperature distribution in the cable and the environment. To use the radial symmetry of the cable geometry, typical electric field simulations neglect the influence of the surrounding soil, due to different dimensions of the cable and the environment and the resulting high computational effort. Here, the environment and its effect on the resulting electric field is considered and the assumption of a possible radial symmetric temperature within the insulation is analyzed. To reduce the computation time, weakly coupled simulations are performed to compute the temperature and the electric field inside the cable insulation, neglecting insulation losses. The results of a weakly coupled simulation are compared against those of a full transient simulation, considering the insulation losses for two common cable insulations with different maximum operation temperatures. Due to the buried depth of HV cables, an approximately radial symmetric temperature distribution within the insulation is obtained for a single cable and cable pairs when, considering a metallic sheath. Furthermore, the simulations show a temperature increase of the earth–air interface above the buried cable that needs to be considered when computing the cable conductor temperature, using the IEC standards.

Hybrid-pair ratio adjustable power splitters for add-on RF shimming and array-compressed parallel transmission.

A ratio adjustable power splitter (RAPS) circuit was recently proposed for add-on RF shimming and array-compressed parallel transmission. Here we propose a new RAPS circuit design based on off-the-shelf components for improved performance and manufacturability. The original RAPS used a pair of home-built Wilkinson splitter and hybrid coupler connected by a pair of connectorized coaxial cables. Here we propose a new hybrid-pair RAPS (or HP-RAPS) circuit that replaces the home-built circuits with two commercially available hybrid couplers and replaces connectorized cables with interchangeable microstrip lines. We derive the relation between the desired splitting ratio and the required phase shifts for HP-RAPS and investigate how to generate arbitrary splitting ratios using paired meandering and straight lines. Several HP-RAPSs with different splitting ratios were fabricated and tested on the workbench and MRI experiments. The splitting ratio of an HP-RAPS circuit has a tan or cot dependence on the meandering line's additional length compared to the straight line. The fabricated HP-RAPSs exhibit accurate splitting ratios as expected (<4% deviations) and generate transmit fields that well agree with predicted fields. They also demonstrated a low insertion loss of 0.33 dB, high output isolation of -26 dB, and acceptable impedance matching of -16 dB. A novel HP-RAPS circuit was developed and implemented. It is easy-to-fabricate/reproduce with minimal expertise. It also preserves the features of the original RAPS circuit (ratio-adjustable, small footprint, etc.) with lower insertion loss.

The Evaluation of Twisted Pair Cable Performance in Circuits with DS18B20 Temperature Sensors

The transmission of data and energy has been widely used over the past few centuries, but in a complex manner and at high cost. Gradually in order to simplify this process and reduce costs, important network cables have appeared, namely: twisted pair cables, coaxial cables, and fiberoptic cables. Thus, instead of various wires, a single cable has become necessary. Within this context, this study seeks to evaluate data transmission performance using two types of Ethernet cables, CAT E5 and CAT E6, in circuits with DS18B20 temperature sensors. The evaluation of the two cables was made by reducing their lengths by 10 meters every two weeks to find the length of cable which would ensure a reliable reading of the sensors for use in the research project entitled “The Evaluation of the Potential Use of Surface Geothermal Energy in the City of Dourados, MS”. The obtained data indicates that CAT E5 cables with lengths less than 70 meters ensure reliable readings close to the real value, while for CAT E6 Ethernet cables this takes place at lengths of less than 80 meters.

A modelling evaluation of electromagnetic fields emitted by buried subsea power cables and encountered by marine animals: Considerations for marine renewable energy development

The expanding marine renewable energy industry will increase the prevalence of electromagnetic fields (EMFs) from power cables in coastal waters. Assessments of environmental impacts are required within licensing/permitting processes and increased prevalence of cables will increase questions concerning EMF emissions and potential cumulative impacts. It is presumed that protecting a cable by burial, may also mitigate EMF emissions and potential impacts on species. Focussing on a bundled high voltage direct current (HVDC) transmission cable, we use computational and interpretive models to explore the influence of cable properties and burial depth on the DC magnetic field (DC-MF) potentially encountered by receptive species. Greater cable pair separation increased the deviations from the geomagnetic field and while deeper burial reduced the deviations, the DC-MF was present at intensities perceivable by receptive species. An animal moving along a cable route may be exposed to variable EMFs due to varied burial depth and that combined with an animal's position in the water column determines the distance from source and EMF exposure. Modelling contextually realistic scenarios would improve assessments of potential effects. We suggest developers and cable industries make cable properties and energy transmission data available, enabling realistic modelling and environmental assessment supporting future developments.

An Adjustment Technique for Tensions in the Cables of Concrete Cable-Stayed Bridges considering the Effect of Cable-Girder Temperature Difference

To make sure the tension adjustment in the cables of concrete cable-stayed bridges is conducted successfully, a new adjustment technique for the tension adjustment is presented, with the cable-girder temperature difference taken into account. The tensions are measured via frequency method. Prior to the tension adjustment, tensions and temperatures of all cables and girders are measured when the ambient temperature is stable, and this set of tensions is taken as reference tensions. During the tension adjustment, the relative variable quantities of the tensions are regarded as the control values, while the vertical displacement in the mid-span section of the main span is regarded as the verification value. After each pair of cables is adjusted, it is required to measure the temperatures of cables and girders as well as the vertical displacement variation in the mid-span section of the main span. To guarantee the structural behavior of entire bridge is controlled, at one-third cable points, two-third cable points and the farthest cable points, the frequencies of each pair of cables as well as the temperatures of each pair of cables and girders should be measured so as to recalculate the cable tensions. After that, these cable tensions are compared with the theoretical ones to ensure the structural behavior of entire bridge in control. Finally, Furong bridge, a concrete cable-stayed bridge with double inclined pylons, is taken as a sample application of this proposed technique. The results of cable tensions in this bridge illustrate the new adjustment technique is both accurate and efficient.

Design and Latency Analyses of an Enhanced Mixed-Signal Coupling Network With Adaptive Noise Cancellation for Power Over Data Lines

Automotive Ethernet is considered to be the backbone of future in-vehicle data communication. The IEEE 802.3bu standard specifies the use of one unshielded twisted pair of copper cables to simultaneously carry data and energy via Power over Data Lines (PoDL). One main challenge in combined data and energy transfer is the distortion of the data channel due to wideband interference from power signals present in the Automotive environment. This paper proposes the design of a novel enhanced coupling network for PoDL that features a noise cancelling current source controlled by an adaptive finite impulse response (FIR) filter for the active attenuation of interfering power signals. The concept of active attenuation was proven for a resistive network, an average attenuation of 92 dB was measured up to 120 MHz. Further analyses show that the cancellation performance heavily relies on low latency of the active filter. It is derived that the provided attenuation decreases exponentially with the frequency for a given time delay and a novel latency management concept called compressed summation is proposed. The approach maximizes the cancellation performance of the proposed filter architecture by exploiting the knowledge of the ideal filter function and effective latency to define the FIR-filter weights.

Synthesis of constructive-technological decisions of regulation of working capacitance of cables of industrial networks

Introduction. Over the past 10 years, the number of industrial networks has more than doubled. At the physical level, all industrial technology networks are based on twisted pair. Purpose. Synthesis of constructive-technological decisions of regulation of electric capacitance of the insulated conductor at a stage of manufacturing of twisted pair of cables of industrial networks. Methodology. The method of secondary charges to determine the capacitance of the insulated conductor by varying the thickness of the solid and foamed polyethylene insulation. Practical value. Effective regulation is provided on the basis of the obtained dependencies of the effective dielectric constant, the tangent of the dielectric loss angle and the capacitance of the insulated conductor on the degree of foaming and the thickness of the protective film of two-layer insulation. At a degree of porosity of 40 %, the dielectric constant decreases by 25 %, the tangent of the dielectric loss angle – by 33 %, the electrical capacitance of the insulated conductor – by 20 %.

Safe Tumbling of Heavy Objects Using a Two-Cable Crane

In heavy industries, large, heavy objects must be tumbled to access features on their bottoms and sides for assembly and maintenance. Traditional manual operations using a single-cable crane are high-risk, and difficult for less experienced workers. Automating the tumbling process is made challenging due to the presence of kinematic and static singularities which are shown to occur when a single-cable crane loses control over the block being tumbled. Here, an autonomous method for safely tumbling a heavy block sitting on a surface using a two-cable crane is presented. Two winches controlling a pair of cables on a crane are coordinated in such a way that a) the block cannot slip on the floor, b) the block is not lifted into the air, and c) the block is under quasi-static balanced control at all times. A control algorithm for coordinating the two winches is developed for safely tumbling a block without slipping or becoming airborne as well as for eliminating the effect of singularities. A small-scale prototype is developed and the control algorithm is implemented and evaluated experimentally.

Space electromagnetic interference analysis of secondary equipment signal cable

In the field of high-voltage transmission and distribution, the secondary equipments are influenced by the electromagnetic coupling effect generated by the primary circuit, which causes strong interference to the signal cable. In this paper, an equivalent circuit model is established for the secondary cables in different forms, namely conventional cable, coaxial cable and twisted pair cable, based on transmission line theory. Based on the model, the responses of these three kinds of signal cables under the impact of spatial plane electromagnetic wave are analysed in frequency domain. Different impedance characteristics of the cables at the near-end and far-end, and different cable layouts, and different injection directions of the electromagnetic wave are considered in the analysis. The response characteristics of different kinds of signal cables subjected to electromagnetic wave are obtained in frequency domain. By comparing the response characteristics of different kinds of signal cables in different conditions, measures to supress the interference from the coupling of electromagnetic wave are obtained. It can be used to guide the selection and cabling of the signal cables for the secondary equipment in power system.

Calculating Millimeter-Wave Modes of Copper Twisted-Pair Cables Using Transformation Optics

Recent research has indicated considerable potential for millimeter-waves in copper access, with data-rate estimations up to 1 Terabit per second for a reach of 100 m. This line of research exploits millimeter-waves and their corresponding higher-order propagation modes inside the twisted pair cable binder. Unlike the conventionally used transmission-line mode (currents through copper wires), the approach relies on the copper and plastics present in these cables to form a low-loss waveguide. Here, we take a closer look at the potential of millimeter-wave propagation in twisted pair cables by refining the idealized assumptions, used by Cioffi et al. , and identifying the limiting factors. To this end, we introduce the concept of transformation optics as an efficient method of calculating the propagating modes on a twisted pair. Leveraging this technique allows us to calculate modal propagation using realistic material parameters, exposing an important trade-off between loss and confinement. Our modeling results yield achievable data rates that are orders of magnitude lower than those achieved under idealized assumptions. According to our results, 1 Terabit per second can be achieved up to a distance of about 10 m over a twisted-pair with a plastic sheath.

A Series-elastic Robot for Back-pain Rehabilitation

This paper addresses the robot-assisted rehabilitation of back pain, an epidemic health problem affecting a large portion of the population. The design is composed of two springs in series connected to an end-effector via a pair of antagonistic cables. The spring and cable arrangement forms an elastic coupling from the actuator to the output shaft. An input-output torque model of the series-elastic mechanism is established and studied numerically. The study also illustrates the variation of the mechanism’s effective stiffness by changing the springs’ position. In addition, we built a prototype of the robotic mechanism and design experiments with a robotic manipulator to experimentally investigate its dynamic characteristics. The experimental results confirm the predicted elasticity between the input motion and the output torque at the end-effector. We also observe an agreement between the data generated by the torque model and data collected from the experiments. An experiment with a full-scale robot and a human subject is carried out to investigate the human-robot interaction and the mechanism behavior.