Search

DC circuit breaker is the key equipment to deal with the interruption of short-circuit current. Compared with the mechanical switch, the solid circuit breaker and the hybrid circuit breaker using the semiconductor device to interrupt the short-circuit current exhibit superiorities in response duration and arc-less characteristics. Massive power devices controlled by corresponding gate drivers which make the semiconductors-based DC circuit breaker bulky and costly are required to withstand the high DC-bus voltage. In this paper, the master-slave concept-based modular circuit breaker is proposed to simplify the gate driver topology. Only one single gate driver is required to control highly compact modular sub-modules consisted of power devices, passive components, and diodes. Moreover, the proposed topology can be easily implemented with high flexibility and low cost. Specifically, the gate control function and voltage equalization for series-connected devices can be realized reliably. The master-slave concept and operation principle of the proposed topology are elaborated and the effectiveness has been demonstrated by both simulation and experimental test.

Series-cascaded Microgrids (MGs) are gaining increasing popularity because of their control flexibility and ability to synthesise high voltage levels from low power rated modules. Several control schemes have been reported for autonomous power sharing in series cascaded microgrids that incorporate dispatchable Distributed Generators (DGs) only. In contrast, this paper develops a series cascaded microgrid formed by dispatchable and non dispatchable DGs. Achieving power balance as well as voltage and frequency regulation in this microgrid configuration is a challenging task. This work proposes a decentralised master slave control scheme that regulates voltage and frequency and maintains power balance. The proposed scheme ensures maximum utilisation of non dispatchables, incorporates autonomous power curtailment under light load conditions, and offers system reliability comparable to the traditional parallel structure. The proposed microgrid configuration and control scheme are thoroughly validated via simulations and experiments under various operating scenarios.

Rate control is the most used operation method for master-slave hydraulic manipulators. However, the trajectory from the master controlled by the operator cannot completely meet the dynamic limitations and flow restriction of the hydraulic manipulator. Continuous large errors and oscillation will occur due to flow restrictions and high-order dynamics beyond the dynamic boundaries. That significantly limits the velocity tracking performance of a hydraulic manipulator. This paper proposes a flow-limited rate control scheme for the master-slave hydraulic manipulators. The variable velocity mapping is developed, adjusting the velocities to meet the pump and valves flow limits. An adaptive robust rate controller of hydraulic manipulators is designed. An adaptive boundary estimator is introduced to estimate the hydraulic manipulator acceleration boundaries, and a variable structure controller is used to plan the velocities to meet dynamic limits. The proposed control scheme was tested on a hydraulic manipulator. The results showed that the control scheme reduced velocity error and avoided the manipulator vibration, so the performance is improved for the hydraulic manipulator.

Voltage fluctuation suppression and reactive power proportional sharing in islanded microgrids (MGs) are often difficult to maintain simultaneously. Hence, a dynamical reconfigurable master–slave control architecture is proposed herein. When a load fluctuates, the leader will be dynamically selected through specific features (such as the output power, output voltage, and power capacity); subsequently, the leader sends his information to all other distributed generators (DGs) as a unified signal in the MG. Meanwhile, the other DGs adjust their local output based on the unified reference to achieve accurate power sharing in each DG. Moreover, system voltage recovery can be realized simultaneously since each DG contains closed-loop voltage control. In addition, for the automatic selection of the leader, a dynamically selected method based on a weight-voting-based differential delay method is proposed herein; the method realizes the unicity and automatic selection of the leader during communication failure. Additionally, the stability of the proposed method is proven mathematically. The results show that the proposed method is stable for any communication period and DG quantity. Furthermore, the communication delay and communication failure are derived mathematically. The results show that the proposed method demonstrates robustness against communication delay. Finally, experimental results verify the effectiveness of the proposed method under communication delays, failures, and power failures.

Helmet theft is a problem that is of concern to the public. Information Technology provides may resolve any problems, like Internet of Things-based system that can detect helmet theft and track the location of the helmet if it's stolen. This system is designed using a microcontroller device, namely Arduino which is attached to the helmet and motorbike with the help of the SIM800L v2, GPS Neo-6m, buzzer, and Bluetooth HC-05 which is connected to the master slave as an indicator of the safety of the helmet. The hardware on the helmet is connected to Firebase Realtime Database server so it can be connected with the user's Android application to monitor the state and location of the helmet. Android application displays maps to determine the position of the helmet, and can display notifications when the helmet is being stolen. The conclusion is this system can detect helmet theft with a maximum distance from the master and slave bluetooth connections of 10 meters, and the average data transmission from hardware to Firebase is 1,1 seconds, and can monitor status of the helmet and track the position of the helmet through the Android application with Android Jelly Bean (v4.3) operating system. &nbsp, Pencurian helm merupakan salah satu masalah yang menjadi perhatian di kalangan masyarakat saat ini. Pemanfaatan Teknologi Informasi memberikan banyak kemudahan untuk mengatasi banyak permasalahan, seperti dengan menggunakan sistem berbasis Internet of Things yang dapat mendeteksi pencurian helm dan melacak lokasi helm jika tercuri. Sistem keamanan helm ini dirancang menggunakan perangkat mikrokontroler yaitu, Arduino yang dipasangkan pada helm dan motor dengan bantuan modul SIM800L v2, GPS Neo-6m, buzzer, dan Bluetooth HC-05 yang dikoneksikan master slave sebagai indikator keamanan pada helm. Perangkat keras pada helm dihubungkan dengan server Firebase Realtime Database sehingga dapat dihubungkan dengan aplikasi Android pengguna untuk memonitor keadaan dan lokasi dari helm. Aplikasi Android menampilkan maps untuk mengetahui posisi helm, dan dapat menampilkan notifikasi apabila helm sedang dalam keadaan tercuri. Kesimpulan dari hasil perancangan sistem keamanan helm yaitu, rancangan sistem pendeteksi helm berbasis IoT dapat mendeteksi pencurian helm dengan jarak maksimal dari koneksi bluetooth master dan slave adalah 10 meter, dan rata-rata pengiriman data dari perangkat keras ke Firebase adalah 1,1 detik, serta dapat melakukan monitoring status helm dan pelacakan posisi helm melalui aplikasi Android dengan sistem operasi Android Jelly Bean(v4.3).

In this article, a model-based sensorless control method which incorporates the orthogonal master-slave adaptive notch filter (ANF) for surface mounted permanent magnet synchronous motor is proposed. Since the rotor position estimation is seriously affected by the harmonics of estimated back-electromotive force (EMF), the orthogonal master-slave ANF is designed to deal with this problem. The orthogonal master-slave ANF is developed based on the ANF with frequency adaptation. The theoretical analysis indicates that the orthogonal master-slave ANF can accurately track the specific harmonics and the fundamental wave of back-EMF. Both the satisfactory harmonics elimination and the fast response speed of filter can also be achieved at the same time. Besides, the proposed frequency adaptation algorithm overcomes the dependence of frequency convergence on the signal amplitude and the problem of “double-frequency oscillation” in the estimated frequency. And since the use of frequency adaptation, the phase-locked loop is unnecessary, which simplifies the system and enhances the reliability. The corresponding experimental results under different conditions demonstrate the effectiveness and the superiority of the proposed method.

How cooperation emerges and persists in a population of selfish agents is a fundamental question in evolutionary game theory. The research shows that collective strategies with master-slave mechanism (CSMSM) defeat tit-for-tat and other well-known strategies in spatial iterated prisoner's dilemma. A CSMSM identifies kin members by means of a handshaking mechanism. If the opponent is identified as non-kin, a CSMSM will always defect. Once two CSMSMs meet, they play master and slave roles. A mater defects and a slave cooperates in order to maximize the master's payoff. CSMSM outperforms non-collective strategies in spatial IPD even if there is only a small cluster of CSMSMs in the population. The existence and performance of CSMSM in spatial iterated prisoner's dilemma suggests that cooperation first appears and persists in a group of collective agents.

This article considers the master-slave Markovian jump complex dynamical networks (CDNs) with multiple time-varying delays by designing a non-fragile sliding mode control mechanism to achieve $${H_\infty }$$ /passive synchronization. First, by introducing a non-fragile sliding surface, master-slave CDNs can achieve $${H_\infty }$$ /passive synchronization, and the state trajectory of CDNs can arrive the sliding surface based on a suitable controller. By applying an appropriate Lyapunov–Krasovskii functional (LKF) that combines triple and four integral terms, using the reciprocal convex combination method and utilizing a few novel integral inequalities, the criterion of $${H_\infty }$$ /passive synchronization is established for master-slave CDNs. Besides, the prospective criterion of $${H_\infty }$$ /passive synchronization can be transformed into the form of linear matrix inequalities. Moreover, reasonability of theoretical results is proved via numerical simulations.

This paper focuses on the finite-time (FT) synchronisation for master-slave periodic neural networks (NNs) with mixed time-varying delays. In order to make full use of the limited network bandwidth...

Ensuring correct functionality is the basic objective of any digital design and this can be done only if the circuit obeys all the timing constraints. Static Timing Analysis is the procedure perfor...

Yaw steering is an important technique for bistatic spaceborne synthetic aperture radar (SAR), traditionally implemented separately at the master and slave satellites, such as the X-band TerraSAR-X/TanDEM-X system. This separate yaw steering method, however, will degrade the illumination synchronization between the master and slave satellites. With the increment in frequency band and master–slave distance, the degradation will get worse, leading to intolerable azimuth resolution degradation or even failure of imaging. To solve this problem, a new joint yaw steering (JYS) method is proposed for bistatic spaceborne SAR with an arbitrary configuration in this letter. The word “joint” means that the master and slave satellites cooperatively work to always make their beams point to an identical point on the Earth’s surface. In this way, the best illumination synchronization can be achieved, contributing to the best available azimuth resolution. The presented approach has been evaluated through computer simulations.

The nodes in WSNs are densely deployed and lots of redundancy exists during the data gathering and sending perceived data straightforwardly to the base station, which leading to consumption of energy in nodes. Existing Clustering algorithms in WSN selects just one group head in the each cluster, where it devours more energy at Cluster head(CH) quickly and which condenses lifetime of the network incredibly. The paper proposes the Advanced and Energy Efficient Master/Slave algorithm to solve this problem. The algorithm reduces the energy consumption of each node by minimizing the direct communication of the nodes with the Base station or CHs by changing the hierarchy in WSN. The moto of the algorithm is to select one master Cluster Head and remaining slave CHs. The algorithm will select Master Cluster Head based on more residual energy, distance, and low packet drop; the remaining become Slave Cluster Heads. The simulation results prove that the Advanced and Energy Efficient Master/Slave algorithm improves throughput and packet delivery ratio(PDR) by decreasing the energy consumption.

The future projects of lunar exploration suppose a wide use of robotic systems of space purposes. The paper tackles the issues of determining phases of in-formation interaction of a cosmonaut with a space humanoid robot in a master-slave mode. The identification of these phases helps to determine the construction features of both master-slave robots and automatic robots designed to assist cosmonauts in the course of their professional activity in long-duration interplanetary missions. Furthermore, the determination of phases of information interaction of a cosmonaut with a space humanoid robot in a master-slave mode is quite topical. The unique experiments with the Fyodor humanoid robot conducted under the Ispytatel space experiment aboard the International Space Station in August-September, 2019, emphasized the need to analyze the obtained results step-by-step.

In this paper, an improved variational adaptive Kalman filter for cooperative localization with inaccurate prior information is proposed, in which the prior scale matrix of the one-step prediction error covariance matrix is adaptively estimated by using the expectation-maximization algorithm. A novel alternate iteration strategy is proposed to reduce the computational complexity of the proposed method. Convergence analysis and theoretical comparisons with the existing advanced adaptive Kalman filtering methods are also provided. Based on this, a new master-slave cooperative localization method is proposed. Lake experiment results of cooperative localization for autonomous underwater vehicles demonstrate the advantages of the proposed method over existing methods. Compared with the cutting-edge adaptive master-slave cooperative localization method, the proposed method has been improved by 22.52% in average localization error but no more than twice computational time is needed.

The fluidic oscillator is an instrument that can continuously generate a spatially sweeping jet entirely based on its internal geometry without any moving parts. However, the traditional fluidic oscillator has an inherent limitation, that is, the spreading angle cannot be controlled independently, rather by the jet volume flow rate and internal geometry. Accordingly, two types of fluidic oscillators based on the master-slave design are developed in current study to decouple this correlation. In both designs, the master layer inherits the similar oscillation mechanisms of a sweeping jet, and the slave layer resembles a steady jet channel. The difference between the two designs is that Design A has a short diverging exit in the slave layer, but Design B adds a long interaction chamber in the exit channel to intensify flow instability. The external flow fields and governing oscillation properties of these two designs are experimentally explored with time-resolved Particle Image Velocimetry (PIV), while the internal flow dynamics and driving oscillation mechanisms are numerically investigated. By fixing the total volume flow rate, the jet spreading angle of Design A can be increased smoothly from 0° to above 100° by increasing the proportion of master layer's flow rate from 0 to 100%. For Design B, the control authority of the master layer is significantly enhanced by adding the interaction chamber in the slave layer. In addition, the added chamber causes notable jet oscillation even when the master layer has none input.

Balanced current sharing and output voltage control of paralleled DC–DC converter modules are essential requirements for enhanced reliability and power capacity. These control goals are challenging due to the load, supply voltage, line impedance uncertainties, inter-couplings of the converters, and open circuit faults. To achieve these goals, this paper proposes two novel adaptive fuzzy backstepping control methods for two sets of paralleled DC–DC converters. The proposed controllers are exercised in a master–slave architecture. First, a master–slave adaptive fuzzy backstepping controller is suggested for a set of paralleled buck converters to deal with matched and mismatched uncertainties, and to ensure balanced current sharing. To counteract uncertainties, as well as interactions among the converters, adaptive fuzzy estimators are employed. However, the suggested control strategy is not applicable to the paralleled boost converters due to their non-minimum-phase nature. Therefore, a novel master–slave adaptive fuzzy backstepping controller with a conventional proportional-integral reference current generator is proposed to encompass paralleled boost converters. Moreover, a simple fault-tolerant structure is suggested to detect the open circuit faults and re-share the inductor currents. The stability of the proposed controllers is guaranteed through the Lyapunov stability theorem. The proposed adaptive fuzzy backstepping control strategies offer good output voltage quality and current sharing, despite the uncertainties, inter-couplings, and open circuit faults. Comparative simulations are carried out on sets of three paralleled buck and boost converters to demonstrate the effectiveness and performance of the new control methods.

This paper investigates a tracking adaptive control issue of the master-slave flexible system with input signal quantisation. Considering the distributed parameter characteristics of the flexible m...

This article presents a novel hybrid algorithm based on the grey-wolf optimizer and whale optimization algorithm, referred here as grey-wolf optimizer–whale optimization algorithm, for the dynamic parametric modelling of a four degree-of-freedom master–slave robot manipulator system. The first part of this work consists of testing the feasibility of the grey-wolf optimizer–whale optimization algorithm by comparing its performance with a grey-wolf optimizer, whale optimization algorithm and particle swarm optimization using 10 benchmark functions. The grey-wolf optimizer–whale optimization algorithm is then used for the model identification of an experimental master–slave robot manipulator system using the autoregressive moving average with exogenous inputs model structure. Obtained results demonstrate that the hybrid algorithm is effective and can be a suitable substitute to solve the parameter identification problem of robot models.

Many kinds of studies have been conducted on Greco-Roman slavery practices and the Christian response to religious and domestic conflicts. However, very little research has been carried out in biblical studies to appraise the rhetoric of Paul’s letter to Philemon and its persuasive implications for handling tensions and dilemmas that emerge from master-servant relationships in the Christian domestic contexts. This paper contributes to the scholarship on Philemon by critically interpreting the persuasiveness of the letter. It exposes Paul’s intentional use of highly emotive argumentations, familial concepts and visual symbols to influence the beliefs, state of mind, values and contemplated actions of his primary audience regarding a particular distressing exigency. It reveals the strong subversive and transformative tone of the letter. The paper contends that the message of Philemon has effective rhetorical power for managing the challenges faced by Christian parents, maids and fictive children in the Christian household. Keywords: Rhetoric, 1st Century Greco-Roman context, master-slave relationship, Christianity, appropriation

Finite-time (FT) synchronization for periodic T–S fuzzy master-slave neural networks (NNs) with distributed delays is addressed in this work. A fuzzy controller is designed for the salve NNs to synchronize the master NNs in FT and a synchronization error system (SES) is derived. Sufficient conditions are established to guarantee that the SES is FT bounded by using the mode and fuzzy basis dependent Lyapunov function. A new algorithm is proposed to obtain the suboptimal boundary of the SES to analyze how the periodic characteristics affect the system boundary. Finally, a numerical example is provided to demonstrate the validity of the fuzzy controller and the iterative algorithm for the boundary.

Teleoperated robots are commonly used in minimally invasive surgery as they can control surgical instruments at a distance. An operator sends the motion command via a master console, which must convert these into suitable slave instrument actuator inputs for intuitive interaction. However, most master-slave systems available to date use incremental task-space control and clutching, which introduces a discontinuity and orientation misalignment between the master control handle and slave instrument, with a consequent impact on task performance. In this article, we proposed a new master manipulator design to compensate for misalignment mechanically. The modular gimbal consists of a passive decoupling mechanism and a wrist locking feature. After describing the mechanisms and its kinematic configuration, we report on a comparative study under controlled conditions, developed to measure the end effector orientation in both compensated and non-compensated scenarios. The results demonstrate that the compensated master console maintains a near constant end effector orientation over the workspace during clutching, showing great promise as a solution to this outstanding open challenge in master-slave manipulation.

This paper investigates adaptive event-triggered [Formula: see text] control for network-based master-slave switched systems subject to actuator saturation and data injection attacks. It is an important and unrecognised issue that the switching signal is affected from both event-triggering scheme and network attacks. An adaptive event-triggering scheme is proposed that can adjust the triggering frequency through a variable threshold based on system performance. Furthermore, considering the impacts of transmission delays and actuator saturation, an event-triggered time-delay error switched system is developed. Subsequently, by utilizing piecewise Lyapunov functional technique, sufficient conditions are derived to render the time-delay error switched system to have an [Formula: see text] performance level. In particular, the coupling between switching instants and data updating instants is analyzed during the system performance analysis. Moreover, sufficient conditions for the desired state-feedback controller gains and event-triggering parameter are presented. Finally, a numerical example is given to verify the effectiveness of the proposed method.

In this paper, we mainly investigate global exponential synchronization for master-slave complex-valued neural networks (CVNNs) under a time-scale impulsive strategy. CVNNs are separated into real and imaginary parts, which lead to two real-valued neural networks (RVNNs). Firstly, impulsive Halanay differential inequality on time scales as well as the comparison between general exponential function and exponential function in timescale sense is given based on the calculus of time scales. Then by constructing the appropriate Lyapunov functional and using the established lemma and proposition, the concepts of average impulsive interval (AII) and average impulsive gain (AIG), some novel synchronization criteria for the given master-slave CVNNs in impulsive form are obtained. Additionally, the convergence rate is estimated explicitly. Finally, one numerical example is given to show the effectiveness of the proposed results.

Because the human arm and leg have a similar skeletal structure, it may be possible to use the leg to operate a robot by the master-slave method. However, operation by the leg with six degrees of freedom has two problems. First, people move their ankle with a curved motion despite intending to move it linearly. Second, it is a burden for the operator to suspend their legs in the air during operation. This study dealt with these problems. For the first problem, we hypothesized that one of the reasons was that the muscle load of a curved motion was smaller than that of a linear motion, and we quantitatively compared them by musculoskeletal analysis. The muscle loads of curved motions were 20% smaller in the anteroposterior direction, 3.1% to 23.8% smaller in the lateral direction, and 10% smaller in the vertical direction than linear motions, which showed that the hypothesis was consistent. Further, comparison of the analysis results with the results of a previous study suggested that subjects unconsciously tried to reduce the muscle load and to move closer to a linear line when they moved their ankle while consciously intending to make a linear motion. For the second problem, we developed two different prototypes of a leg support device. An experiment to evaluate the effectiveness of these devices showed that subjective exercise intensity of the tasks in the experiment using the devices was 40% or more less than that without the device, which proved the effectiveness of the devices.

The recent experiences of extreme weather events highlight the significance of boosting the resilience of distribution systems. In this situation, the resilience of distribution systems planning leads to an efficient solution for protecting the system from these events via line hardening and the installation of distributed generators (DGs). For this aim, this study presents a new two-stage stochastic mixed-integer linear programming model (SMILP) to hedge against natural disaster uncertainty. The first stage involves making investment decisions about line hardening and DG installation. Then, in the second stage, the dynamic microgrids are created according to a master-slave concept with the ability of integrating distributed generators to minimize the cost of loss of load in each uncertain outage scenario. In particular, this paper presents an approach to select the line damage scenarios for the SMILP. In addition, the operational strategies such as load control capability, microgrid formation and network reconfiguration are integrated into the distribution system plans for resilience improvement in both planning and emergency response steps. The simulation results for an IEEE 33-bus test system demonstrate the effectiveness of the proposed model in improving disaster-induced the resilience of distribution systems.

In this study, an adaptive fuzzy-neural-network-imitating sliding-mode control (AFNNISMC) is developed for a parallel-inverter system in an islanded micro-grid (MG) via a master-slave current sharing strategy. For ensuring the system-level stability, an entire dynamic model is constructed by viewing the parallel-inverter system as a whole. First, a total sliding-mode control (TSMC) scheme, and the TSMC plus an adaptive observer to form an adaptive TSMC (ATSMC) framework are designed for the parallel-inverter system. Then, a four-layer fuzzy neural network (FNN) is investigated to imitate the TSMC law to improve the system robustness, overcome the drawback of the dependence on detailed system dynamics, and deal with the chattering phenomena caused by the TSMC. According to the Lyapunov stability theorem and the projection algorithm, network parameters in the FNN are regulated online by employing the approximation error between the FNN and the TSMC law to ensure the convergence of the network and the stability of the control system. Thereby, the performance of high power quality and high-precision current sharing between inverters can be guaranteed even if system uncertainties exist. Moreover, the proposed AFNNISMC system can achieve the seamless disconnection and re-connection of slave inverters from and into an energized parallel-inverter system, which improves the redundancy and operation flexibility. In addition, numerical simulations and experimental results are given to demonstrate the feasibility and effectiveness of the proposed AFNNISMC scheme. Furthermore, performance comparisons with the ATSMC strategy and a conventional proportional-integral control (PIC) framework are provided to verify the superiority of the proposed scheme.

Manufacturing process variations and transistor’s aging effects are two major concerns for reliable design of nano-scale digital circuits. Correct functionality of flip-flops (FFs), as one of the most important elements in digital circuits, plays a key role in reliability of modern circuit designs. In this paper, a timing reliability improvement technique is proposed for master-slave FFs considering the impacts of process variations and aging effects. In this technique, the internal circuitry of the FF is restructured in order to improve the reliability by reducing the stress time (i.e. the time of being ON) of the transistors which are stacked in the feedback loop. Using Monte-Carlo based HSPICE simulations, the efficacy of the restructuring-based reliability improvement technique is shown considering various experimental conditions (i.e. different process variation ratios and lifetime values). The experimental results show that, the lifetime reliability of Master-Slave FFs improved by 22% in expense of 3% area overhead, 8% propagation delay absolute change, and 6% absolute power change in the presence of 20% variation ratio and 9 years of operation time.

To improve power supply reliability when enabling energy exchange among multiple dc microgrids (MGs) as well as effectively avoid overload or uncertainty, this paper presents a distributed cluster cooperation strategy through establishing a master-slave control framework over two-layer switching topologies. According to the physical cluster structure of multiple dc MGs, all distributed generators (DGs) within each dc MG cluster are divided into one master-DG and multiple slave-DGs. All master-DGs, allowed to information interaction among multiple MG clusters, constitute the master control layer; whereas slave-DGs, enabled to information exchange within each MG cluster, then together form the slave control layer. Once the stable operation is realized among all master-DGs, the stability of all slave-DGs can be automatically driven by their respective master-DGs. Eventually the weighted average voltage of all DGs can be regulated to their references, meanwhile, the accurate current sharing can be simultaneously realized not only within each dc MG cluster but also among multiple dc MG clusters. All controllers are fully distributed and can be applied in all sparse two-layer switching network topologies, control time constant related sufficient conditions are also derived to ensure the whole system stability. The effectiveness of the results is verified through different cases in MATLAB/SimPowerSystems.

This paper introduces a novel successive-intersection-approximation-based power flow method for integrated transmission and distribution networks (I-T&D). In this method, the entire I-T&D is split into the transmission network part, distribution network part, and boundary part. Then, alternate iterations are processed between a transmission network (TN) and several distribution networks (DNs) by exchanging the voltage and power injection of boundary buses. Particularly, the voltage magnitude of the boundary buses will be modified every two iterations by obtaining an intersection with the results in the previous two iterations. The local quadratic convergence of the method is proved strictly. The numerical experiment demonstrates that the proposed method has the same accuracy as the method based on the global model. Also, better convergence and efficiency can be achieved under the proposed method compared with the master-slave-splitting method in several different circumstances, DNs with loops, DNs with distributed generations, DNs with on-load tap changers, large-scale systems, etc. Besides, the proposed method is applied in the contingency analysis, achieving satisfying convergence and efficiency.

With the increasing penetration of renewable resources and the DC nature loads, voltage source converter (VSC) based DC distribution systems take an important position in the future smart grid architecture due to many distinguishing features. However, DC distribution systems face frequent power disturbances and multi-mode swithcing problem, how to achieve better DC voltage control and reasonable power sharing performance under various disturbances is still a challenge. After analyzing the control structure and master–slave (M–S) method, an equal loading rate based M–S method is proposed based on the power sharing capability of the VSC station. Moreover, error analysis of the proposed M–S method is conducted and a correction method for the proposed M–S method is developed. The proposed M–S method not only preserves the advantage of M–S method, but also changes the power instructions accordingly based on the operation state of the whole DC distribution system. Moreover, the proposed M–S method is simple and easy to implement. Lastly, simulations of a three-terminal VSC based DC distribution system are conducted in PSCAD/EMTDC to validate the effectiveness of the proposed M–S method.

Teleoperation systems require a human-centered approach in which the kinematic mapping is intuitive and straightforward for the operators. However, a mismatch in the degrees-of-freedom (DoFs) between master and slave could result in an asymmetrical teleoperation system. That is an obstacle for intuitive kinematic mapping. In particular, it is even more challenging when the missing DoF is a pure rotational DoF, since the rotation group SO(3) is a nonlinear Riemannian manifold. This letter is concerned with an asymmetric teleoperation system, where the master subsystem can provide 6-DoF pose sensing while the slave subsystem only has 5 DoFs. The rotation along the missing DoF, which is configuration-dependent, is mapped to a geodesic curve in SO(3). We define and prove the closed-form solution of the perpendicular curve to the geodesic curve. Based on the perpendicular curve, we develop a novel Incomplete Orientation Mapping (IOM) approach to avoid the motion in the missing DoF. By comparing with two baseline methods, the experimental results demonstrate that the proposed method can discard the rotational motion along the missing DoF for all configurations, while preserving the remaining rotations.

Purpose Existing robot-assisted minimally invasive surgery (RMIS) system lacks of force feedback, and it cannot provide the surgeon with interaction forces between the surgical instruments and patient’s tissues. This paper aims to restore force sensation for the RMIS system and evaluate effect of force sensing in a master-slave manner. Design/methodology/approach This paper presents a four-DOF surgical instrument with modular joints and six-axis force sensing capability and proposes an incremental position mode master–slave control strategy based on separated position and orientation to reflect motion of the end of master manipulator to the end of surgical instrument. Ex-vivo experiments including tissue palpation and blunt dissection are conducted to verify the effect of force sensing for the surgical instrument. An experiment of trajectory tracking is carried out to test precision of the control strategy. Findings Results of trajectory tracking experiment show that this control strategy can precisely reflect the hand motion of the operator, and the results of the ex-vivo experiments including tissue palpation and blunt dissection illustrate that this surgical instrument can measure the six-axis interaction forces successfully for the RMIS. Originality/value This paper addresses the important role of force sensing and force feedback in RMIS, clarifies the feasibility to apply this instrument prototype in RMIS for force sensing and provides technical support of force feedback for further clinical application.

In this study, we evaluate the coordination tracking control problem of a flexible master–slave teleoperation system. The system under consideration is based on a dynamic model described by a set of partial differential equations. Existing research on bilateral controllers is based on teleoperation systems composed of rigid master robots and rigid or flexible slave robots. In this work, we consider teleoperation systems with flexible master and slave robots. We dynamically model flexible master–slave manipulators using partial differential equations. Based on the dynamic model, a bilateral coordination controller is developed to realize the coordination angle tracking and vibration suppression of flexible master–slave manipulators. The teleoperation system is proven to be asymptotically stable under the control scheme. Numerical simulation results illustrate that the proposed controller is effective.

This paper investigates the exponential synchronization of Master–Slave Markovian jump complex networks with nonlinear perturbation via a sampled-data sliding mode control. First introduce an impro...

This paper addresses the convergence analysis on the guaranteed robust $H_{\infty }$ control for master–slave generalized uncertain neural networks (GUNNs). Synchronization problems are raised up due to the existence of the disturbance loading and parameter uncertainties. In order to cope with the encountered robustness issues, a dual geometric sequence division-dependent augmented Lyapunov–Krasovskii functional is newly constructed, which contains state variable-based integral forms with unfixed intervals. Meanwhile, the convex combination technique is employed to deal with not only the parameter uncertainties but also the derivative of delay $\dot {\tau } (t)$ . To ensure the GUNNs to be globally asymptotically stable with the guaranteed $H_{\infty }$ performance in the case of disturbance and parameters uncertainties, a controller is designed using the liner matrix inequalities technique. Numerical examples show that, in the sense of the prescribed $H_{\infty}$ performance, this proposed work achieves expected results on the error synchronization system.

The aim of this work is to design a robust output-based controller for a robotic manipulator (RM) with a master–slave configuration (MSC). The trajectories of the slave robot manipulator (SRM) must fulfil two types of constraints. The first corresponds to the boundaries of the obstacles placed in the given workspace. The second is related to the boundaries of the workspace. The controller must ensure the collision avoidance of the obstacles and the end-effector of the SRM should remain inside of the workspace. The proposed controller satisfies a state feedback structure with time-varying gains. The time-variable gains include an integral compensation that guarantees the collision avoidance with the obstacle satisfying the boundary of the workspace, which is the main contribution of this study. The solution of a matrix inequality characterises the zone of convergence and the suboptimal control gains. A set of numerical simulations using a MSC based on a couple of two-link RMs illustrates the advantages obtained with the proposed method. Also, a set of experimental results demonstrate the effectiveness of the proposed controller.