Journal of Control Science and Engineering http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. Development of Intermediate Cooling Technology and Its Control for Two-Stand Plate Rolling Mon, 05 Dec 2016 13:30:08 +0000 http://www.hindawi.com/journals/jcse/2016/4192186/ In a plate rolling production line, thermomechanically controlled processing is critical for plate quality. In this paper, a set of intermediate cooling equipment of a two-stand plate mill with super density nozzles, medium pressure, and small flow is developed. Based on a simplified dynamic model, a cooling control scheme with combined feedforward, feedback, and adaptive algorithms is put forward. The new controlled rolling process and the highly efficient control system improve the controlled rolling efficiency by an average of 17.66%. The proposed intermediate cooling system can also effectively inhibit the growth of austenite grain, improve the impact toughness and yield strength of Q345B steel plate, reduce the formation of secondary oxide scale on the plate surface and the chromatic aberration of the plate surface, and greatly improve the surface quality of the steel plate. Fei Zhang, Wei Yu, and Tao Liu Copyright © 2016 Fei Zhang et al. All rights reserved. Discrete PID-Type Iterative Learning Control for Mobile Robot Thu, 01 Dec 2016 13:02:14 +0000 http://www.hindawi.com/journals/jcse/2016/2320746/ Through studying tracking problems of the wheeled mobile robot, this paper proposed a discrete iterative learning control approach based on PID with strong adaptability, fast convergence, and small error. This algorithm used discrete PID to filter rejection and restrained the influence of interference and noise on trajectory tracking, which made it more suitable for engineering application. The PID-type iterative learning convergence condition and certification procedure are presented. The results of simulation reveal that the PID-type ILC holds the features of simplicity, strong robustness, and high repeating precision and can well meet the control requirement of nonlinear discrete system. Hongbin Wang, Jian Dong, and Yueling Wang Copyright © 2016 Hongbin Wang et al. All rights reserved. Two Novel Grey System Models and Their Applications on Landslide Forecasting Thu, 24 Nov 2016 12:48:49 +0000 http://www.hindawi.com/journals/jcse/2016/5727160/ For the small sample poor information, grey model is one of the good forecasting models. However, the simulation curve of original data is not consistent with that of the data by translations. In this paper, we present two novel grey system models, that is, generalized grey model and generalized discrete grey model. Compared with grey model, we prove that the simulation curve of original data is consistent with that of the new data by translations for the novel grey model, which was also demonstrated by the results of practical numerical examples. De-Yi Ma and Jian-Lin Li Copyright © 2016 De-Yi Ma and Jian-Lin Li. All rights reserved. Impulsive Control Strategy for a Nonautonomous Food-Chain System with Multiple Delays Thu, 24 Nov 2016 12:22:22 +0000 http://www.hindawi.com/journals/jcse/2016/6126545/ A nonautonomous food-chain system with Holling II functional response is studied, in which multiple delays of digestion are also considered. By applying techniques in differential inequalities, comparison theorem in ordinary differential equations, impulsive differential equations, and functional differential equations, some effective control strategies are obtained for the permanence of the system. Furthermore, effects of some important coefficients and delays on the permanence of the system are intuitively and clearly shown by series of numerical examples. Baodan Tian, Yanhong Qiu, and Yucai Ding Copyright © 2016 Baodan Tian et al. All rights reserved. Robust Control of Wind Turbines by Using Singular Perturbation Method and Linear Parameter Varying Model Mon, 21 Nov 2016 11:55:00 +0000 http://www.hindawi.com/journals/jcse/2016/2830736/ The maximum power point tracking problem of variable-speed wind turbine systems is studied in this paper. The wind conversion systems contain both mechanical part and electromagnetic part, which means the systems have time scale property. The wind turbine systems are modeled using singular perturbation methodology. A linear parameter varying (LPV) model is developed to approximate the nonlinear singularly perturbed model. Then stability and robust properties of the open-loop linear singularly perturbed system are analyzed using linear matrix inequalities (LMIs). An algorithm of designing a stabilizing state-feedback controller is proposed which can guarantee the robust property of the closed-loop system. Two numerical examples are provided to demonstrate the effectiveness of the control scheme proposed. Yan Zhang, Zhengfan Liu, Zhong Yang, and Haifei Si Copyright © 2016 Yan Zhang et al. All rights reserved. Reachable Set Estimation for Discrete-Time Systems with Interval Time-Varying Delays and Bounded Disturbances Sun, 20 Nov 2016 09:40:47 +0000 http://www.hindawi.com/journals/jcse/2016/5214147/ The reachable set estimation problem for discrete-time systems with delay-range-dependent and bounded disturbances is investigated. A triple-summation term, the upper bound, and the lower bound of time-varying delay are introduced into the Lyapunov function. In this case, an improved delay-range-dependent criterion is established for the addressed problem by constructing the appropriate Lyapunov functional, which guarantees that the reachable set of discrete-time systems with time-varying delay and bounded peak inputs is contained in the ellipsoid. It is worth mentioning that the initial value of the system does not need to be zero. Then, the reachable set estimation problem for time-delay systems with polytopic uncertainties is investigated. The effectiveness and the reduced conservatism of the derived results are demonstrated by an illustrative example. Jiemei Zhao and Yin Sheng Copyright © 2016 Jiemei Zhao and Yin Sheng. All rights reserved. On Couple-Group Consensus of Multiagent Networks with Communication and Input Time Delays Thu, 10 Nov 2016 14:46:49 +0000 http://www.hindawi.com/journals/jcse/2016/2625497/ This paper investigated the couple-group consensus problems of the multiagent networks with the influence of communication and input time delays. Based on the frequency-domain theory, some algebraic criteria are addressed analytically. From the results, it is found that the input time delays and the coupling strengths between agents of the systems play a crucial role in reaching group consensus. The convergence of the system is independent of the communication delays, but it will affect the convergence rate of the system. Finally, several simulated examples are provided to verify the validity and correctness of our theoretical results. Liang-hao Ji and Xin-yue Zhao Copyright © 2016 Liang-hao Ji and Xin-yue Zhao. All rights reserved. A -Infinity Control for Path Tracking with Fuzzy Hyperbolic Tangent Model Thu, 10 Nov 2016 14:11:59 +0000 http://www.hindawi.com/journals/jcse/2016/9072831/ To achieve the goal of driver-less underground mining truck, a fuzzy hyperbolic tangent model is established for path tracking on an underground articulated mining truck. Firstly, the sample data of parameters are collected by the driver controlling articulated vehicle at a speed of 3 m/s, including both the lateral position deviation and the variation of heading angle deviation. Then, according to the improved adaptive BP neural network model and deriving formula of mediation rate of error estimator by the method of Cauchy robust, the weights are identified. Finally, -infinity control controller is designed to control steering angle. The results of hardware-in-the-loop simulation show that lateral position deviation, heading angle deviation, and steering angle of the vehicle can be controlled, respectively, at 0.024 m, 0.08 rad, and 0.21 rad. All the deviations are asymptotically stable, and error control is in less than 2%. The method is demonstrated to be effective and reliable in path tracking for the underground vehicles. Guangsi Shi, Jue Yang, Xuan Zhao, Yanfeng Li, Yalun Zhao, and Jian Li Copyright © 2016 Guangsi Shi et al. All rights reserved. Neural Network Based Fault Detection and Diagnosis System for Three-Phase Inverter in Variable Speed Drive with Induction Motor Thu, 10 Nov 2016 08:17:46 +0000 http://www.hindawi.com/journals/jcse/2016/1286318/ Recently, electrical drives generally associate inverter and induction machine. Therefore, inverter must be taken into consideration along with induction motor in order to provide a relevant and efficient diagnosis of these systems. Various faults in inverter may influence the system operation by unexpected maintenance, which increases the cost factor and reduces overall efficiency. In this paper, fault detection and diagnosis based on features extraction and neural network technique for three-phase inverter is presented. Basic purpose of this fault detection and diagnosis system is to detect single or multiple faults efficiently. Several features are extracted from the Clarke transformed output current and used in neural network as input for fault detection and diagnosis. Hence, some simulation study as well as hardware implementation and experimentation is carried out to verify the feasibility of the proposed scheme. Results show that the designed system not only detects faults easily, but also can effectively differentiate between multiple faults. These results prove the credibility and show the satisfactory performance of designed system. Results prove the supremacy of designed system over previous feature extraction fault systems as it can detect and diagnose faults in a single cycle as compared to previous multicycles detection with high accuracy. Furqan Asghar, Muhammad Talha, and Sung Ho Kim Copyright © 2016 Furqan Asghar et al. All rights reserved. Reliability Assessment of Cloud Computing Platform Based on Semiquantitative Information and Evidential Reasoning Sun, 06 Nov 2016 09:17:23 +0000 http://www.hindawi.com/journals/jcse/2016/2670210/ A reliability assessment method based on evidential reasoning (ER) rule and semiquantitative information is proposed in this paper, where a new reliability assessment architecture including four aspects with both quantitative data and qualitative knowledge is established. The assessment architecture is more objective in describing complex dynamic cloud computing environment than that in traditional method. In addition, the ER rule which has good performance for multiple attribute decision making problem is employed to integrate different types of the attributes in assessment architecture, which can obtain more accurate assessment results. The assessment results of the case study in an actual cloud computing platform verify the effectiveness and the advantage of the proposed method. Hang Wei and Pei-Li Qiao Copyright © 2016 Hang Wei and Pei-Li Qiao. All rights reserved. A Nonlinear Robust Controller Design for Ship Dynamic Positioning Based on -Gain Disturbance Rejection Tue, 01 Nov 2016 10:32:51 +0000 http://www.hindawi.com/journals/jcse/2016/9275065/ In ship motion control process, it is difficult to design ship controller due to the effects of environmental disturbances such as wind, waves, current, and unmodelled dynamics. In order to solve these problems, a nonlinear robust controller based on -gain disturbance rejection is proposed in this paper. To steer ships to the desired position, an error feedback control law on account of Lyapunov functions is designed. Then, to satisfy the -gain disturbance rejection, proper parameters are chosen based on the system dissipative property. In order to verify the performance of the proposed controller, the MATLAB simulation results in two situations which are without and with the effects of environmental disturbances are demonstrated. Guoqing Xia, Jingjing Xue, Ang Guo, Caiyun Liu, and Xinghua Chen Copyright © 2016 Guoqing Xia et al. All rights reserved. Investigations of the Gas-Liquid Multiphase System Involving Macro-Instability in a Baffled Stirred Tank Reactor Mon, 31 Oct 2016 14:27:44 +0000 http://www.hindawi.com/journals/jcse/2016/3075321/ Bubble Sauter Mean Diameter (SMD) in gas-liquid multiphase system is of particular interest and the quantification of gas characteristics is still a challenge today. In this contribution, multiphase Computational Fluid Dynamic (CFD) simulations are combined with Population Balance Model (PBM) to investigate the bubble SMD in baffled stirred tank reactor (STR). Hereby, special attention is given to the phenomenon known as the fluid macro-instability (MI), which is a large-scale low-frequency fluid velocity variation in baffled STRs, since the fluid MIs have a dominating influence on the bubble breakage and coalescence processes. The simulations, regarding the fluid velocity, are validated with Laser Doppler Anemometry (LDA) experiments, in which the instant radial velocity is analyzed through Fast Fourier Transform (FFT) spectrum. The frequency peaks of the fluid MIs are found both in the simulation and in the experiment with a high degree of accuracy. After the validation, quantitative predictions of overall bubble SMD with and without MIs are carried out. Due to the accurate prediction of the fluid field, the influence of the fluid MI to bubble SMD is presented. This result provides more adequate information for engineers working in the field of estimating bubble SMDs in baffled STRs. Shuo Zhang, Jan Talaga, David Müller, Michal Dylag, and Günter Wozny Copyright © 2016 Shuo Zhang et al. All rights reserved. Vulnerability Analysis of CSP Based on Stochastic Game Theory Mon, 24 Oct 2016 13:56:00 +0000 http://www.hindawi.com/journals/jcse/2016/4147251/ With the development of industrial informatization, the industrial control network has gradually become much accessible for attackers. A series of vulnerabilities will therefore be exposed, especially the vulnerability of exclusive industrial communication protocols (ICPs), which has not yet been attached with enough emphasis. In this paper, stochastic game theory is applied on the vulnerability analysis of clock synchronization protocol (CSP), one of the pivotal ICPs. The stochastic game model is built strictly according to the protocol with both Man-in-the-Middle (MIM) attack and dependability failures being taken into account. The situation of multiple attack routes is considered for depicting the practical attack scenarios, and the introduction of time aspect characterizes the success probabilities of attackers actions. The vulnerability analysis is then realized through determining the optimal strategies of attacker under different states of system, respectively. Jiajun Shen and Dongqin Feng Copyright © 2016 Jiajun Shen and Dongqin Feng. All rights reserved. A New Scheme on Synchronization of Commensurate Fractional-Order Chaotic Systems Based on Lyapunov Equation Sun, 16 Oct 2016 08:42:33 +0000 http://www.hindawi.com/journals/jcse/2016/5975491/ This paper proposes a new fractional-order approach for synchronization of a class of fractional-order chaotic systems in the presence of model uncertainties and external disturbances. A simple but practical method to synchronize many familiar fractional-order chaotic systems has been put forward. A new theorem is proposed for a class of cascade fractional-order systems and it is applied in chaos synchronization. Combined with the fact that the states of the fractional chaotic systems are bounded, many coupled items can be taken as zero items. Then, the whole system can be simplified greatly and a simpler controller can be derived. Finally, the validity of the presented scheme is illustrated by numerical simulations of the fractional-order unified system. Hua Wang, Hang-Feng Liang, Peng Zan, and Zhong-Hua Miao Copyright © 2016 Hua Wang et al. All rights reserved. A Novel Relative Navigation Control Strategy Based on Relation Space Method for Autonomous Underground Articulated Vehicles Tue, 11 Oct 2016 11:18:27 +0000 http://www.hindawi.com/journals/jcse/2016/2352805/ This paper proposes a novel relative navigation control strategy based on the relation space method (RSM) for articulated underground trackless vehicles. In the RSM, a self-organizing, competitive neural network is used to identify the space around the vehicle, and the spatial geometric relationships of the identified space are used to determine the vehicle’s optimal driving direction. For driving control, the trajectories of the articulated vehicles are analyzed, and data-based steering and speed control modules are developed to reduce modeling complexity. Simulation shows that the proposed RSM can choose the correct directions for articulated vehicles in different tunnels. The effectiveness and feasibility of the resulting novel relative navigation control strategy are validated through experiments. Fengqian Dou, Yu Meng, Li Liu, and Qing Gu Copyright © 2016 Fengqian Dou et al. All rights reserved. Control of Power Converters for Emerging Applications of Power Electronics Tue, 04 Oct 2016 11:11:26 +0000 http://www.hindawi.com/journals/jcse/2016/9235283/ Ahmed M. Massoud, Shehab Ahmed, Ayman S. Abdel-Khalik, Ahmed A. Elserougi, and Khaled H. Ahmed Copyright © 2016 Ahmed M. Massoud et al. All rights reserved. Improved Distributed Model Predictive Control with Control Planning Set Wed, 28 Sep 2016 11:59:20 +0000 http://www.hindawi.com/journals/jcse/2016/8167931/ We focus on distributed model predictive control algorithm. Each distributed model predictive controller communicates with the others in order to compute the control sequence. But there are not enough communication resources to exchange information between the subsystems because of the limited communication network. This paper presents an improved distributed model predictive control scheme with control planning set. Control planning set algorithm approximates the future control sequences by designed planning set, which can reduce the exchange information among the controllers and can also decrease the distributed MPC controller calculation demand without degrading the whole system performance much. The stability and system performance analysis for distributed model predictive control are given. Simulations of the four-tank control problem and multirobot multitarget tracking problem are illustrated to verify the effectiveness of the proposed control algorithm. Wei Chen Copyright © 2016 Wei Chen. All rights reserved. An Improved Backstepping-Based Controller for Three-Dimensional Trajectory Tracking of a Midwater Trawl System Wed, 07 Sep 2016 16:40:04 +0000 http://www.hindawi.com/journals/jcse/2016/1358412/ An improved backstepping control method for three-dimensional trajectory tracking of a midwater trawl system is investigated. A new mathematical model of the trawl system while considering the horizontal expansion effect of two otter boards is presented based on the Newton Euler method. Subsequently, an active path tracking strategy of the trawl system based on the backstepping method is proposed. The nonstrict feedback characteristic of the proposed model employs a control allocation method and several parallel nonlinear PID (Proportion Integration Differentiation) controllers to eliminate the high-order state variables. Then, the stability analysis by the Lyapunov Stability Theory shows that the proposed controller can maintain the stability of the trawl system even with the presence of external disturbances. To validate the proposed controller, a simulation comparison with a linear PID controller was conducted. The simulation results illustrate that the improved backstepping controller is effective for three-dimensional trajectory tracking of the midwater trawl system. Zhao Yan, Yun sheng Mao, and Cheng gang Liu Copyright © 2016 Zhao Yan et al. All rights reserved. Decentralized Control of a Group of Homogeneous Vehicles in Obstructed Environment Wed, 31 Aug 2016 16:16:18 +0000 http://www.hindawi.com/journals/jcse/2016/7192371/ The presented solution is a decentralized control system with a minimal informational interaction between the objects in the group. During control and path planning the obstacles are transformed into repellers by the synthesized controls. The main feature distinguishing the developed approach from the potential fields method is that the vehicle moves in the fields of forces depending not only on the mutual positions of a robot and an obstacle but also on the additional variables allowing solving the problem of robot’s path planning using a distributed control system (Pshikhopov and Ali, 2011). Unlike the work by Pshikhopov and Ali, 2011, here an additional dynamic variable is used to introduce stable and unstable states depending on the state variables of the robot and the neighboring objects. The local control system of each vehicle uses only the values of its own speeds and coordinates and those of the neighboring objects. There is no centralized control algorithm. In the local control algorithms the obstacles are represented as vehicles being a part of the group which allows us to unify the control systems for heterogeneous groups. An analysis was performed that proves existence and asymptotic stability of the steady state motion modes. The preformed simulation confirms the synthesis and analysis results. Vyacheslav Pshikhopov, Mikhail Medvedev, Alexander Kolesnikov, Roman Fedorenko, and Boris Gurenko Copyright © 2016 Vyacheslav Pshikhopov et al. All rights reserved. Decentralized Robust Adaptive Output Feedback Stabilization for Interconnected Nonlinear Systems with Uncertainties Tue, 30 Aug 2016 05:56:20 +0000 http://www.hindawi.com/journals/jcse/2016/3656578/ Based on adaptive nonlinear damping, a novel decentralized robust adaptive output feedback stabilization comprising a decentralized robust adaptive output feedback controller and a decentralized robust adaptive observer is proposed for a large-scale interconnected nonlinear system with general uncertainties, such as unknown nonlinear parameters, bounded disturbances, unknown nonlinearities, unmodeled dynamics, and unknown interconnections, which are nonlinear function of not only states and outputs but also unmodeled dynamics coming from other subsystems. In each subsystem, the proposed stabilization only has two adaptive parameters, and it is not needed to generate an additional dynamic signal or estimate the unknown parameters. Under certain assumptions, the proposed scheme guarantees that all the dynamic signals in the interconnected nonlinear system are bounded. Furthermore, the system states and estimate errors can approach arbitrarily small values by choosing the design parameters appropriately large. Finally, simulation results illustrated the effectiveness of the proposed scheme. Qiang Yang, Ming Zhu, Tao Jiang, Jin He, Jianying Yuan, and Jianda Han Copyright © 2016 Qiang Yang et al. All rights reserved. Gait Tracking Control of Quadruped Robot Using Differential Evolution Based Structure Specified Mixed Sensitivity Robust Control Sun, 28 Aug 2016 16:47:36 +0000 http://www.hindawi.com/journals/jcse/2016/8760215/ This paper proposed a control algorithm that guarantees gait tracking performance for quadruped robots. During dynamic gait motion, such as trotting, the quadruped robot is unstable. In addition to uncertainties of parameters and unmodeled dynamics, the quadruped robot always faces some disturbances. The uncertainties and disturbances contribute significant perturbation to the dynamic gait motion control of the quadruped robot. Failing to track the gait pattern properly propagates instability to the whole system and can cause the robot to fall. To overcome the uncertainties and disturbances, structured specified mixed sensitivity robust controller was proposed to control the quadruped robot legs’ joint angle positions. Before application to the real hardware, the proposed controller was tested on the quadruped robot’s leg planar dynamic model using MATLAB. The proposed controller can control the robot’s legs efficiently even under uncertainties from a set of model parameter variations. The robot was also able to maintain its stability even when it was tested under several terrain disturbances. Petrus Sutyasadi and Manukid Parnichkun Copyright © 2016 Petrus Sutyasadi and Manukid Parnichkun. All rights reserved. Generalized Minimum Variance Control for MDOF Structures under Earthquake Excitation Thu, 25 Aug 2016 07:56:50 +0000 http://www.hindawi.com/journals/jcse/2016/7458654/ Control of a multi-degree-of-freedom structural system under earthquake excitation is investigated in this paper. The control approach based on the Generalized Minimum Variance (GMV) algorithm is developed and presented. Our approach is a generalization to multivariable systems of the GMV strategy designed initially for single-input-single-output (SISO) systems. Kanai-Tajimi and Clough-Penzien models are used to generate the seismic excitations. Those models are calculated using the specific soil parameters. Simulation tests using a 3DOF structure are performed and show the effectiveness of the control method. Lakhdar Guenfaf and Mohamed Azira Copyright © 2016 Lakhdar Guenfaf and Mohamed Azira. All rights reserved. The Feedback Control Strategy of the Takagi-Sugeno Fuzzy Car-Following Model with Two Delays Wed, 24 Aug 2016 09:26:15 +0000 http://www.hindawi.com/journals/jcse/2016/4581428/ Considering the driver’s sensing the headway and velocity the different time-varying delays exist, respectively, and the sensitivity of drivers changes with headway and speed. Introducing the fuzzy control theory, a new fuzzy car-following model with two delays is presented, and the feedback control strategy of the new fuzzy car-following model is studied. Based on the Lyapunov function theory and linear matrix inequality (LMI) approach, the sufficient condition that the existence of the fuzzy controller is given making the closed-loop system is asymptotic, stable; namely, traffic congestion phenomenon can effectively be suppressed, and the controller gain matrix can be obtained via solving linear matrix inequality. Finally, the simulation examples verify that the method which suppresses traffic congestion and reduces fuel consumption and exhaust emissions is effective. Cong Zhai, Weiming Liu, and Ling Huang Copyright © 2016 Cong Zhai et al. All rights reserved. Fault Diagnosis and Fault Tolerant Control for Non-Gaussian Singular Time-Delayed Stochastic Distribution Systems with Disturbance Based on the Rational Square-Root Model Wed, 24 Aug 2016 06:59:59 +0000 http://www.hindawi.com/journals/jcse/2016/9563481/ For the non-Gaussian singular time-delayed stochastic distribution control (SDC) system with unknown external disturbance where the output probability density function (PDF) is approximated by the rational square-root B-spline basis function, a robust fault diagnosis and fault tolerant control algorithm is presented. A full-order observer is constructed to estimate the exogenous disturbance and an adaptive observer is used to estimate the fault size. A fault tolerant tracking controller is designed using the feedback of distribution tracking error, fault, and disturbance estimation to let the postfault output PDF still track desired distribution. Finally, a simulation example is included to illustrate the effectiveness of the proposed algorithms and encouraging results have been obtained. Yuancheng Sun and Zhanhong Liang Copyright © 2016 Yuancheng Sun and Zhanhong Liang. All rights reserved. Robust Finite-Time Terminal Sliding Mode Control for a Francis Hydroturbine Governing System Mon, 22 Aug 2016 08:48:34 +0000 http://www.hindawi.com/journals/jcse/2016/2518734/ The robust finite-time control for a Francis hydroturbine governing system is investigated in this paper. Firstly, the mathematical model of a Francis hydroturbine governing system is presented and the nonlinear vibration characteristics are analyzed. Then, on the basis of finite-time control theory and terminal sliding mode scheme, a new robust finite-time terminal sliding mode control method is proposed for nonlinear vibration control of the hydroturbine governing system. Furthermore, the designed controller has good robustness which could resist external random disturbances. Numerical simulations are employed to verify the effectiveness and superiority of the designed finite-time sliding mode control scheme. The approach proposed in this paper is simple and also provides a reference for relevant hydropower systems. Fengjiao Wu, Junling Ding, and Zhengzhong Wang Copyright © 2016 Fengjiao Wu et al. All rights reserved. Synchronization of the Fractional-Order Brushless DC Motors Chaotic System Thu, 11 Aug 2016 12:17:43 +0000 http://www.hindawi.com/journals/jcse/2016/1236210/ Based on the extension of Lyapunov direct method for nonlinear fractional-order systems, chaos synchronization for the fractional-order Brushless DC motors (BLDCM) is discussed. A chaos synchronization scheme is suggested. By means of Lyapunov candidate function, the theoretical proof of chaos synchronization is addressed. The numerical results show that the chaos synchronization scheme is valid. Shiyun Shen and Ping Zhou Copyright © 2016 Shiyun Shen and Ping Zhou. All rights reserved. Interior Point Algorithm for Multi-UAVs Formation Autonomous Reconfiguration Tue, 09 Aug 2016 15:25:23 +0000 http://www.hindawi.com/journals/jcse/2016/9095372/ Here the problem of designing multi-UAVs formation autonomous reconfiguration is considered. Combined with three kinds of cost functions, nonlinear dynamic equations, and four inequality constraints, one nonlinear multiobjective optimization problem is constructed. After applying weighted sum method and separating all equality or inequality constraints, the former nonlinear multiobjective optimization problem can be converted into a standard nonlinear single objective optimization problem. Then the interior point algorithm is applied to solve it. Further some improvements are proposed to avoid rank deficiency of some matrices. The equivalence property between multiobjective optimization and single objective optimization through weighted sum method is proved. Finally the efficiency of the proposed strategy can be confirmed by the simulation example results. Wang Jian-hong and Rana Javed Masood Copyright © 2016 Wang Jian-hong and Rana Javed Masood. All rights reserved. A New Robust Method for Mobile Robot Multifloor Navigation in Distributed Life Science Laboratories Sun, 31 Jul 2016 07:46:24 +0000 http://www.hindawi.com/journals/jcse/2016/3589395/ A new robust method is proposed for multifloor navigation in distributed Life Science Laboratories. This method proposes a solution for many technical issues including (a) mapping and localization with ceiling landmarks and a StarGazer module for achieving an accurate and low cost multifloor navigation system, (b) a new method for path planning to navigate across multiple floor environments called backbone method and embedded transportation management system, (c) elevator environment handler with the necessary procedures to interact with the elevator presenting a new approach for elevator entry button and internal buttons detection, and (d) communication system to get an expandable network; this method utilizes a TCP/IP network for the communication. Many experiments in real Life Science Laboratories proved the efficient performance of the developed multifloor navigation system in life science environment. Ali A. Abdulla, Hui Liu, Norbert Stoll, and Kerstin Thurow Copyright © 2016 Ali A. Abdulla et al. All rights reserved. PMSM Rotor Position Detection Based on Hybrid Optical Encoder and R-Signal Zero-Setting Scheme Mon, 25 Jul 2016 09:52:29 +0000 http://www.hindawi.com/journals/jcse/2016/2712643/ Rotor position detection is a prerequisite for achieving good control performance of PMSM. For a PMSM control system based on an optical encoder, it is a difficulty to detect rotor position and achieve R-Signal zero-setting. To solve the problem, a hybrid optical encoder is used in the paper by which a scheme for rotor position detection and R-Signal zero-setting is proposed. This encoder can do absolute and incremental rotor position detection simultaneously; here, the former is used for acquiring imprecise rotor position and the latter is for precise rotor position. Firstly, two detection methods of the encoder are analyzed, and a scheme for rotor position detection is proposed: absolute rotor position is used for motor starting before achieving R-Signal zero-setting; once achieving R-Signal zero-setting, incremental rotor position detection that has high precision is adopted. Then a novel scheme for R-Signal zero-setting is emphatically proposed. Finally, the simulation is conducted. Results show that rotor position detection and R-Signal zero-setting can be achieved by the proposed scheme. Yaoqiang Wang, Xiaoyong Ma, Mingdong Wang, and Chong Cao Copyright © 2016 Yaoqiang Wang et al. All rights reserved. Estimation of Stator Resistance and Rotor Flux Linkage in SPMSM Using CLPSO with Opposition-Based-Learning Strategy Thu, 21 Jul 2016 13:10:58 +0000 http://www.hindawi.com/journals/jcse/2016/5781467/ Electromagnetic parameters are important for controller design and condition monitoring of permanent magnet synchronous machine (PMSM) system. In this paper, an improved comprehensive learning particle swarm optimization (CLPSO) with opposition-based-learning (OBL) strategy is proposed for estimating stator resistance and rotor flux linkage in surface-mounted PMSM; the proposed method is referred to as CLPSO-OBL. In the CLPSO-OBL framework, an opposition-learning strategy is used for best particles reinforcement learning to improve the dynamic performance and global convergence ability of the CLPSO. The proposed parameter optimization not only retains the advantages of diversity in the CLPSO but also has inherited global exploration capability of the OBL. Then, the proposed method is applied to estimate the stator resistance and rotor flux linkage of surface-mounted PMSM. The experimental results show that the CLPSO-OBL has better performance in estimating winding resistance and PM flux compared to the existing peer PSOs. Furthermore, the proposed parameter estimation model and optimization method are simple and with good accuracy, fast convergence, and easy digital implementation. Jian He and Zhao-Hua Liu Copyright © 2016 Jian He and Zhao-Hua Liu. All rights reserved.