Journal of Control Science and Engineering http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Linear Feedback Synchronization Used in the Three-Dimensional Duffing System Wed, 24 Jun 2015 06:42:54 +0000 http://www.hindawi.com/journals/jcse/2015/617870/ It has been realized that synchronization using linear feedback control method is efficient compared to nonlinear feedback control method due to the less computational complexity and the synchronization error. For the problem of feedback synchronization of Duffing chaotic system, in the paper, we firstly established three-dimensional Duffing system by method of variable decomposition and, then, studied the synchronization of Duffing chaotic system and designed the control law based on linear feedback control and Lyapunov stability theory. It is proved theoretically that the two identical integer order chaotic systems are synchronized analytically and numerically. Jian-qun Han, Xu-dong Shi, and Hong Sun Copyright © 2015 Jian-qun Han et al. All rights reserved. A Novel Stability Analysis of Uncertain Switched Systems with Time-Varying Delays Wed, 10 Jun 2015 07:54:13 +0000 http://www.hindawi.com/journals/jcse/2015/745175/ This paper deals with the stability of switched systems with time-varying delay. The time-varying system parameters are assumed to be norm-bounded. Based on a novel switched time-varying Lyapunov functional method, some new LMI-based sufficient conditions have been obtained to ensure the exponential stability for the uncertain switched delays systems. Finally, the proposed method is applied to a numerical example and the simulative results are also given. Ganji Huang, Shixian Luo, Linna Wei, and Wuhua Chen Copyright © 2015 Ganji Huang et al. All rights reserved. Model-Based Development of Control Systems for Forestry Cranes Tue, 02 Jun 2015 09:09:14 +0000 http://www.hindawi.com/journals/jcse/2015/256951/ Model-based methods are used in industry for prototyping concepts based on mathematical models. With our forest industry partners, we have established a model-based workflow for rapid development of motion control systems for forestry cranes. Applying this working method, we can verify control algorithms, both theoretically and practically. This paper is an example of this workflow and presents four topics related to the application of nonlinear control theory. The first topic presents the system of differential equations describing the motion dynamics. The second topic presents nonlinear control laws formulated according to sliding mode control theory. The third topic presents a procedure for model calibration and control tuning that are a prerequisite to realize experimental tests. The fourth topic presents the results of tests performed on an experimental crane specifically equipped for these tasks. Results of these studies show the advantages and disadvantages of these control algorithms, and they highlight their performance in terms of robustness and smoothness. Pedro La Hera and Daniel Ortíz Morales Copyright © 2015 Pedro La Hera and Daniel Ortíz Morales. All rights reserved. Observer-Based Robust Passive Control for a Class of Uncertain Neutral Systems: An Integral Sliding Mode Approach Tue, 02 Jun 2015 06:21:40 +0000 http://www.hindawi.com/journals/jcse/2015/308681/ The problem of integral sliding mode control (ISMC) with passivity is investigated for a class of uncertain neutral systems with time-varying delay (NTSTD) and external disturbance. The system states are unavailable. An ISMC strategy is proposed based on the state estimate. By employing a novel sliding functional, a new sufficient criterion of robust asymptotic stability and passivity for both the error system and the sliding mode (SM) dynamic system is derived via linear matrix inequality (LMI) technique. Then, a SM controller is synthesized to guarantee the reachability of the sliding surface predefined in the state estimate space. Finally, a numerical example shows the feasibility and superiority of the obtained result. Ruiping Xu, Zhen Liu, Cunchen Gao, and Huimin Xiao Copyright © 2015 Ruiping Xu et al. All rights reserved. Spacecraft Actuator Diagnosis with Principal Component Analysis: Application to the Rendez-Vous Phase of the Mars Sample Return Mission Tue, 26 May 2015 14:21:37 +0000 http://www.hindawi.com/journals/jcse/2015/204918/ This paper presents a fault detection and isolation (FDI) approach in order to detect and isolate actuators (thrusters and reaction wheels) faults of an autonomous spacecraft involved in the rendez-vous phase of the Mars Sample Return (MSR) mission. The principal component analysis (PCA) has been adopted to estimate the relationships between the various variables of the process. To ensure the feasibility of the proposed FDI approach, a set of data provided by the industrial “high-fidelity” simulator of the MSR and representing the opening (resp., the rotation) rates of the spacecraft thrusters (resp., reaction wheels) has been considered. The test results demonstrate that the fault detection and isolation are successfully accomplished. Othman Nasri, Imen Gueddi, Philippe Dague, and Kamal Benothman Copyright © 2015 Othman Nasri et al. All rights reserved. In-Flight Self-Alignment Method Aided by Geomagnetism for Moving Basement of Guided Munitions Sun, 24 May 2015 07:11:37 +0000 http://www.hindawi.com/journals/jcse/2015/425698/ Due to power-after-launch mode of guided munitions of high rolling speed, initial attitude of munitions cannot be determined accurately, and this makes it difficult for navigation and control system to work effectively and validly. An in-flight self-alignment method aided by geomagnetism that includes a fast in-flight coarse alignment method and an in-flight alignment model based on Kalman theory is proposed in this paper. Firstly a fast in-flight coarse alignment method is developed by using gyros, magnetic sensors, and trajectory angles. Then, an in-flight alignment model is derived by investigation of the measurement errors and attitude errors, which regards attitude errors as state variables and geomagnetic components in navigation frame as observed variables. Finally, fight data of a spinning projectile is used to verify the performance of the in-flight self-alignment method. The satisfying results show that (1) the precision of coarse alignment can attain below 5°; (2) the attitude errors by in-flight alignment model converge to 24′ at early of the latter half of the flight; (3) the in-flight alignment model based on Kalman theory has better adaptability, and show satisfying performance. Shuang-biao Zhang, Xing-cheng Li, and Zhong Su Copyright © 2015 Shuang-biao Zhang et al. All rights reserved. Power Forecasting of Combined Heating and Cooling Systems Based on Chaotic Time Series Tue, 12 May 2015 13:10:56 +0000 http://www.hindawi.com/journals/jcse/2015/174203/ Theoretic analysis shows that the output power of the distributed generation system is nonlinear and chaotic. And it is coupled with the microenvironment meteorological data. Chaos is an inherent property of nonlinear dynamic system. A predicator of the output power of the distributed generation system is to establish a nonlinear model of the dynamic system based on real time series in the reconstructed phase space. Firstly, chaos should be detected and quantified for the intensive studies of nonlinear systems. If the largest Lyapunov exponent is positive, the dynamical system must be chaotic. Then, the embedding dimension and the delay time are chosen based on the improved C-C method. The attractor of chaotic power time series can be reconstructed based on the embedding dimension and delay time in the phase space. By now, the neural network can be trained based on the training samples, which are observed from the distributed generation system. The neural network model will approximate the curve of output power adequately. Experimental results show that the maximum power point of the distributed generation system will be predicted based on the meteorological data. The system can be controlled effectively based on the prediction. Liu Hai, Song Yong, and Du Qingfu Copyright © 2015 Liu Hai et al. All rights reserved. Human Simulated Intelligent Control with Double-Direction Dead-Zone Compensation for Joint Motion Control of a Large-Sized Boom System Sun, 10 May 2015 14:32:08 +0000 http://www.hindawi.com/journals/jcse/2015/349186/ Joint motion control of a 52-meter-long five-boom system driven by proportional hydraulic system is developed. It has been considered difficult due to strong nonlinearities and parametric uncertainties, the effect of which increases with the size of booms. A human simulated intelligent control scheme is developed to improve control performance by modifying control mode and control parameters. In addition, considering the negative effects caused by frequent and redundant reverse actions of the proportional valve, a double-direction compensation scheme is proposed to deal with the dead-zone nonlinearity of proportional valve. Sinusoidal motions are implemented on a real boom system. The results indicate that HSIC controller can improve control accuracy, and dead-zone nonlinearity is effectively compensated by proposed compensation scheme without introducing frequent reverse actions of proportional valve. Rongsheng Liu, Yingjie Gao, Yulin Yang, and Yanlong Liu Copyright © 2015 Rongsheng Liu et al. All rights reserved. The Exact Linearization and LQR Control of Semiactive Connected Hydropneumatic Suspension System Thu, 30 Apr 2015 07:55:47 +0000 http://www.hindawi.com/journals/jcse/2015/690917/ Based on differential geometry theory, the nonlinear system of connected hydropneumatic suspension was transformed to a linear one. What is more, it realized the decoupling and inverter between the control variables and system outputs. With LQR (Linear Quadratic Regulator) control theory, a semiactive system has been developed for connected hydropneumatic suspension in this paper. By AMESim/Simulink cosimulation, the results show that the semiactive connected hydropneumatic suspension decreases the vibration of upper vehicle quickly and reduces the impact acceleration strongly both in displacement and inroll angle. Moreover, the semiactive suspension could increase the suspension dynamic deflection, which would make the system reach balance quickly and keep small vibration amplitude under the effect of disturbance. Xuyang Cao, Linlin Cao, and Dianlong Wang Copyright © 2015 Xuyang Cao et al. All rights reserved. Model Predictive Control of NCS with Data Quantization and Bounded Arbitrary Time Delays Sun, 19 Apr 2015 12:55:12 +0000 http://www.hindawi.com/journals/jcse/2015/259480/ The model predictive control for constrained discrete time linear system under network environment is considered. The bounded time delay and data quantization are assumed to coexist in the data transmission link from the sensor to the controller. A novel NCS model is specially established for the model predictive control method, which casts the time delay and data quantization into a unified framework. A stability result of the obtained closed-loop model is presented by applying the Lyapunov method, which plays a key role in synthesizing the model predictive controller. The model predictive controller, which parameterizes the infinite horizon control moves into a single state feedback law, is provided which explicitly considers the satisfaction of input and state constraints. Two numerical examples are given to illustrate the effectiveness of the derived method. Jimin Yu, Yanan Xie, and Xiaoming Tang Copyright © 2015 Jimin Yu et al. All rights reserved. Chaotic Secure Communication Systems with an Adaptive State Observer Tue, 31 Mar 2015 12:29:03 +0000 http://www.hindawi.com/journals/jcse/2015/471913/ This paper develops a new digital communication scheme based on using a unified chaotic system and an adaptive state observer. The proposed communication system basically consists of five important elements: signal modulation, chaotic encryption, adaptive state observer, chaotic decryption, and signal demodulation. A sequence of digital signals will be delivered from the transmitter to the receiver through a public channel. It is rather reasonable that if the number of signals delivered on the public channel is fewer, then the security of such communication system is more guaranteed. Therefore, in order to achieve this purpose, a state observer will be designed and its function is to estimate full system states only by using the system output signals. In this way, the signals delivered on the public channel can be reduced mostly. According to these estimated state signals, the original digital sequences are then retrieved completely. Finally, experiment results are provided to verify the applicability of the proposed communication system. Wei-Der Chang, Shun-Peng Shih, and Chih-Yung Chen Copyright © 2015 Wei-Der Chang et al. All rights reserved. Robust Tracking Control for Robotic Manipulator via Fuzzy Logic System and Approaches Mon, 30 Mar 2015 07:09:52 +0000 http://www.hindawi.com/journals/jcse/2015/459431/ Based on fuzzy logic system (FLS) and control methodologies, a robust tracking control scheme is proposed for robotic system with uncertainties and external disturbances. FLS is employed to implement the framework of computed torque control (CTC) method via its approximate capability which is used to attenuate the nonlinearity of robotic manipulator. The robust control can guarantee robustness to parametric and dynamics uncertainties and also attenuate the effect of immeasurable external disturbances entering the system. Moreover, a quadratic stability approach is used to reduce the conservatism of the conventional robust control approach. It can be guaranteed that all signals in the closed-loop are bounded by employing the proposed robust tracking control. The validity of the proposed control scheme is shown by simulation of a two-link robotic manipulator. Kun Mu, Cong Liu, and Jinzhu Peng Copyright © 2015 Kun Mu et al. All rights reserved. Reducing Computational Overhead by Improving the CRI and IRI Implication Step Thu, 26 Mar 2015 11:58:04 +0000 http://www.hindawi.com/journals/jcse/2015/725258/ In conventional SISO fuzzy expert systems (-element input, -element output), the implication step requires the operations using compositional rule-based inference (CRI) and individual rule-based inference (IRI). However, this introduces excessive complexity. This paper proposes two methods, sort compositional rule-based inference (SCRI) and sort individual rule-based inference (SIRI) aiming at reducing both temporal and spatial complexity by changing the operation of the implication step to log2. We also propose a divide-and-conquer technique, called Quicksort, to verify the accuracy of SCRI and SIRI algorithms deployment to easily outperform the CRI and IRI methods. Thoai Phu Vo and Joy Iong-Zong Chen Copyright © 2015 Thoai Phu Vo and Joy Iong-Zong Chen. All rights reserved. Combining Multiple Strategies for Multiarmed Bandit Problems and Asymptotic Optimality Wed, 25 Mar 2015 09:15:21 +0000 http://www.hindawi.com/journals/jcse/2015/264953/ This brief paper provides a simple algorithm that selects a strategy at each time in a given set of multiple strategies for stochastic multiarmed bandit problems, thereby playing the arm by the chosen strategy at each time. The algorithm follows the idea of the probabilistic -switching in the -greedy strategy and is asymptotically optimal in the sense that the selected strategy converges to the best in the set under some conditions on the strategies in the set and the sequence of . Hyeong Soo Chang and Sanghee Choe Copyright © 2015 Hyeong Soo Chang and Sanghee Choe. All rights reserved. Observer Design for a Class of Nonlinear Descriptor Systems: A Takagi-Sugeno Approach with Unmeasurable Premise Variables Wed, 25 Mar 2015 06:54:43 +0000 http://www.hindawi.com/journals/jcse/2015/636909/ The Takagi-Sugeno (T-S) fuzzy observer for dynamical systems described by ordinary differential equations is widely discussed in the literature. The aim of this paper is to extend this observer design to a class of T-S descriptor systems with unmeasurable premise variables. In practice, the computation of solutions of differential-algebraic equations requires the combination of an ordinary differential equations (ODE) routine together with an optimization algorithm. Therefore, a natural way permitting to estimate the state of such a system is to design a procedure based on a similar numerical algorithm. Beside some numerical difficulties, the drawback of such a method lies in the fact that it is not easy to establish a rigorous proof of the convergence of the observer. The main result of this paper consists in showing that the state estimation problem for a class of T-S descriptor systems can be achieved by using a fuzzy observer having only an ODE structure. The convergence of the state estimation error is studied using the Lyapunov theory and the stability conditions are given in terms of linear matrix inequalities (LMIs). Finally, an application to a model of a heat exchanger pilot process is given to illustrate the performance of the proposed observer. J. Soulami, A. El Assoudi, M. Essabre, M. Habibi, and E. El Yaagoubi Copyright © 2015 J. Soulami et al. All rights reserved. Discrete Second-Order Sliding Mode Adaptive Controller Based on Characteristic Model for Servo Systems Tue, 17 Mar 2015 08:57:41 +0000 http://www.hindawi.com/journals/jcse/2015/405376/ Considering the varying inertia and load torque in high speed and high accuracy servo systems, a novel discrete second-order sliding mode adaptive controller (DSSMAC) based on characteristic model is proposed, and a command observer is also designed. Firstly, the discrete characteristic model of servo systems is established. Secondly, the recursive least square algorithm is adopted to identify time-varying parameters in characteristic model, and the observer is applied to predict the command value of next sample time. Furthermore, the stability of the closed-loop system and the convergence of the observer are analyzed. The experimental results show that the proposed method not only can adapt to varying inertia and load torque, but also has good disturbance rejection ability and robustness to uncertainties. Zhihong Wang, Yifei Wu, Wei Chen, Xiang Wang, Jian Guo, and Qingwei Chen Copyright © 2015 Zhihong Wang et al. All rights reserved. A New Energy-Efficient Data Transmission Scheme Based on DSC and Virtual MIMO for Wireless Sensor Network Wed, 04 Mar 2015 11:06:01 +0000 http://www.hindawi.com/journals/jcse/2015/904274/ Energy efficiency in wireless sensor network (WSN) is one of the primary performance parameters. For improving the energy efficiency of WSN, we introduce distributed source coding (DSC) and virtual multiple-input multiple-output (MIMO) into wireless sensor network and then propose a new data transmission scheme called DSC-MIMO. DSC-MIMO compresses the source data using distributed source coding before transmitting, which is different from the existing communication schemes. Data compression can reduce the length of the data and improve the energy efficiency. In addition, DSC-MIMO does not require the cluster heads to collect the data of the source nodes, which reduces the frequencies of data transmission and saves energy. In the simulation, we analyze the energy consumption of DSC-MIMO. The results indicate that DSC-MIMO can effectively reduce the energy consumption and improve the energy efficiency of the whole wireless sensor network. Na Li, Liwen Zhang, and Bing Li Copyright © 2015 Na Li et al. All rights reserved. Design of Internal Model Control Based on an Optimal Control for a Servo System Sun, 01 Mar 2015 14:20:42 +0000 http://www.hindawi.com/journals/jcse/2015/689767/ This paper describes a design of internal model control based on an optimal control for a servo system. The control system has the feedback based on the proposed disturbance compensator in the disturbance response. The compensator is designed to become the denominator of the transfer function without a dead time in the disturbance responses. The disturbance response of the proposed method is faster than that of the previous method. Hiromitsu Ogawa, Ryo Tanaka, Takahiro Murakami, and Yoshihisa Ishida Copyright © 2015 Hiromitsu Ogawa et al. All rights reserved. New Absolute Stability Conditions of Lur’e Systems with Time-Varying Delay Sat, 28 Feb 2015 14:14:53 +0000 http://www.hindawi.com/journals/jcse/2015/520737/ This paper is focused on the absolute stability of Lur’e systems with time-varying delay. Based on the quadratic separation framework, a complete delay-decomposing Lyapunov-Krasovskii functional is constructed. By considering the relationship between the time-varying delay and its varying interval, improved delay-dependent absolute stability conditions in terms of linear matrix inequalities (LMIs) are obtained. Moreover, the derived conditions are extended to systems with time-varying structured uncertainties. Finally, a numerical example is given to show the advantage over existing literatures. Wei Wang and Hong-Bing Zeng Copyright © 2015 Wei Wang and Hong-Bing Zeng. All rights reserved. Aeroelastic Dynamic Response and Control of an Aeroelastic System with Hysteresis Nonlinearities Thu, 26 Feb 2015 17:49:23 +0000 http://www.hindawi.com/journals/jcse/2015/258315/ A state feedback control law based on the sliding mode control method is derived for the aeroelastic response and flutter suppression of a two-dimensional airfoil section with hysteresis nonlinearity in pitch. An observer is constructed to estimate the unavailable state variables of the system. With the control law designed, nonlinear effect of time delay between the control input and actuator is investigated by a numerical approach. The closed-loop system including the observer and nonlinear controller is asymptotically stable. The simulation results show that the observer can give precise estimations for the plunge displacement and the velocities in pitch and plunge and that the controller is effective for flutter suppression. The time delay between the control input and actuator may jeopardize the control performance and cause high-frequency vibrations. Xingzhi Xu, Yakui Gao, and Weiguo Zhang Copyright © 2015 Xingzhi Xu et al. All rights reserved. Analysis of Urban Car Owners Commute Mode Choice Based on Evolutionary Game Model Thu, 26 Feb 2015 11:53:42 +0000 http://www.hindawi.com/journals/jcse/2015/291363/ With the aggravation of the traffic congestion in the city, car owners will have to give up commuting with private cars and take the public transportation instead. The paper uses the replication dynamic mechanism to simulate the learning and adjustment mechanism of the automobile owners commuting mode selection. The evolutionary stable strategy is used to describe the long-term evolution of competition game trend. Finally we simulate equilibrium and stability of an evolution of the game under a payoff imbalance situation. The research shows that a certain proportion of car owners will choose public transit under the pressure of public transport development and heavy traffic, and the proportion will be closely related to the initial conditions and urban transportation development policy. Huawei Gong and Wenzhou Jin Copyright © 2015 Huawei Gong and Wenzhou Jin. All rights reserved. System Identification of Heat-Transfer Process of Frequency Induction Furnace for Melting Copper Based on Particle Swarm Algorithm Wed, 25 Feb 2015 16:40:24 +0000 http://www.hindawi.com/journals/jcse/2015/502828/ An adaptive evolutionary strategy in standard particle swarm optimization is introduced. Adaptive evolution particle swarm optimization is constructed to improve the capacity of global search. A method based on adaptive evolution particle swarm optimization for identification of continuous system with time delay is proposed. The basic idea is that the identification of continuous system with time delay is converted to an optimization of continuous nonlinear function. The adaptive evolution particle swarm optimization is utilized to find an optimal solution of continuous nonlinear function. Convergence conditions are given by the convergence analysis based on discrete time linear dynamic system theory. Numerical simulation results show that the proposed method is effective for a general continuous system with time delay and the system of heat-transfer process of frequency induction furnace for melting copper. Zhi-gang Jia and Xing-xuan Wang Copyright © 2015 Zhi-gang Jia and Xing-xuan Wang. All rights reserved. Stability Analysis of Pneumatic Cabin Pressure Regulating System with Complex Nonlinear Characteristics Tue, 24 Feb 2015 12:16:24 +0000 http://www.hindawi.com/journals/jcse/2015/871621/ Stability of pneumatic cabin pressure regulating system with complex nonlinear characteristics is considered. The mathematical model of each component is obtained and given in detail. The governing equations of the considered system consist of 8 differential equations. In the circumstance, commonly used methods of nonlinear system analysis are not applicable. Therefore a new method is proposed to construct phase plane trajectories numerically. The calculation steps are given in detail. And convergence region of numerical calculation and limits on step size is defined. The method is applied constructing phase plane trajectories for considered cabin pressure regulating system. Phase plane analysis shows that there exists a limit cycle, which is responsible for pressure pulsating in aircraft cabin. After parameters adjustment, excellent stability characteristics are acquired. And the validity of this method is confirmed by the simulation. Xinhua Zheng, Lili Xie, and Lizhuo Liu Copyright © 2015 Xinhua Zheng et al. All rights reserved. Less Conservative Optimal Robust Control of a 3-DOF Helicopter Mon, 23 Feb 2015 09:49:54 +0000 http://www.hindawi.com/journals/jcse/2015/720203/ This work proposes an improved technique for design and optimization of robust controllers norm for uncertain linear systems, with state feedback, including the possibility of time-varying the uncertainty. The synthesis techniques used are based on LMIs (linear matrix inequalities) formulated on the basis of Lyapunov’s stability theory, using Finsler’s lemma. The design has used the addition of the decay rate restriction, including a parameter γ in the LMIs, responsible for decreasing the settling time of the feedback system. Qualitative and quantitative comparisons were made between methods of synthesis and optimization of the robust controllers norm, seeking alternatives with lower cost and better performance that meet the design restrictions. A practical application illustrates the efficiency of the proposed method with a failure purposely inserted in the system. L. F. S. Buzachero, E. Assunção, M. C. M. Teixeira, and E. R. P. da Silva Copyright © 2015 L. F. S. Buzachero et al. All rights reserved. An Energy Distance Aware Clustering Protocol with Dual Cluster Heads Using Niching Particle Swarm Optimization for Wireless Sensor Networks Wed, 11 Feb 2015 12:35:14 +0000 http://www.hindawi.com/journals/jcse/2015/849281/ Energy efficient utilization is an important criteria and factor that affects the design of wireless sensor networks (WSNs). In this literature, we propose an energy distance aware clustering protocol with Dual Cluster Heads using Niching Particle Swarm Optimization (DCH-NPSO). The protocol selects two cluster heads in each cluster, the Master Cluster Head (MCH) and the Slave Cluster Head (SCH), and the selection needs to consider the network state information carefully and deliberately. Simulation results show that the protocol we proposed can balance the energy dissipation and extend the network lifetime effectively. Dexin Ma and Pengmin Xu Copyright © 2015 Dexin Ma and Pengmin Xu. All rights reserved. A New BFGS Algorithm Using the Decomposition Matrix of the Correction Matrix to Obtain the Search Directions Sat, 31 Jan 2015 06:58:19 +0000 http://www.hindawi.com/journals/jcse/2015/674617/ We present an improved method for determining the search direction in the BFGS algorithm. Our approach uses the equal inner product decomposition method for positive-definite matrices. The decomposition of an approximated Hessian matrix expresses a correction formula that is independent from the exact line search. This decomposed matrix is used to compute the search direction in a new BFGS algorithm. Li Liu Copyright © 2015 Li Liu. All rights reserved. Obstacle Avoidance Algorithm for 7-DOF Redundant Anthropomorphic Arm Wed, 28 Jan 2015 14:38:56 +0000 http://www.hindawi.com/journals/jcse/2015/540259/ To deal with the problem of obstacle avoidance for redundant robots, an obstacle avoidance algorithm based on the internal motion of the 7-DOF redundant anthropomorphic arm is presented. The motion of that critical points move away from the closest points on the obstacles is defined as obstacle avoiding motion. Two transitioning variables were used to make a smooth, continuous transition between the primary and the secondary tasks. Using this approach, the robot can get the target configuration while avoiding the obstacles. Finally, the validity of the obstacle avoidance algorithm based on transitioning between tasks is manifested by simulation. The results show that, for the obstacle avoiding problem, the redundant robot not only can realize the obstacle avoidance, but also prevents the conflict between tasks by the proposed approach. Haoyu Shen, Hongtao Wu, Bai Chen, Yanjie Jiang, and Cheng Yan Copyright © 2015 Haoyu Shen et al. All rights reserved. Nonlinear Integral Sliding Mode Control for a Second Order Nonlinear System Wed, 28 Jan 2015 10:00:15 +0000 http://www.hindawi.com/journals/jcse/2015/218198/ A nonlinear integral sliding-mode control (NISMC) scheme is proposed for second order nonlinear systems. The new control scheme is characterized by a nonlinear integral sliding manifold which inherits the desired properties of the integral sliding manifold, such as robustness to system external disturbance. In particular, compared with four kinds of sliding mode control (SMC), the proposed control scheme is able to provide better transient performances. Furthermore, the proposed scheme ensures the zero steady-state error in the presence of a constant disturbance or an asymptotically constant disturbance is proved by Lyapunov stability theory and LaSalle invariance principle. Finally, both the theoretical analysis and simulation examples demonstrate the validity of the proposed scheme. Xie Zheng, Xie Jian, Du Wenzheng, and Cheng Hongjie Copyright © 2015 Xie Zheng et al. All rights reserved. Novel Approach to Preview Control for a Class of Continuous-Time Systems Tue, 27 Jan 2015 08:19:42 +0000 http://www.hindawi.com/journals/jcse/2015/745137/ This paper explicates a new method of designing a preview controller for a class of continuous-time systems. The augmented error system is constructed by the error system with the derivative of the tracking error signal, the state equation, and an identical equation of the derivative of the control input, which transforms a tracking problem into a regulation problem. Therefore, in the paper, the performance index contains the derivative of the control input. Based on the theory of optimal control, the regulator problem of the augmented error system is solved. Thus, the controller with preview compensation for the original system is deduced. The response speed of the closed-loop system is accelerated by the previewed demand output. A final numerical example is given to illustrate the validity of the proposed method. Fucheng Liao, Yujie Xu, and Jiang Wu Copyright © 2015 Fucheng Liao et al. All rights reserved. Cloud Model-Based Energy Management Strategy for Parallel Hybrid Vehicles Sun, 18 Jan 2015 14:33:32 +0000 http://www.hindawi.com/journals/jcse/2015/141654/ Using the uncertain conversion capacity between the expressions of quantitative and qualitative concept in the cloud model, an energy management strategy based on cloud model is developed for parallel hybrid vehicles (PHVs). By the driver input and the state of charge (SOC) of the energy storage, a set of rules are developed to effectively determine the torque split between the internal combustion engine (ICE) and the electric motor. An analysis of the simulation results is conducted using ADVISOR in order to verify the effectiveness of the proposed control strategy. It is confirmed that the control scheme can be used to improve fuel economy and emission of the hybrid vehicles. Xiaolan Wu, Guifang Guo, and Zhifeng Bai Copyright © 2015 Xiaolan Wu et al. All rights reserved.