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1

Comparative investigations of nonlinear and linear observers for a highly manoeuvrable target in sliding mode guidance

Wang Y., Sun M., Du S., Chen Z.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 2

233--245

EN

Target manoeuvre is one of the key factors affecting guidance accuracy. To intercept highly maneuverable targets, a second-order sliding-mode guidance law, which is based on the super-twisting algorithm, is designed without depending on any information about the target motion. In the designed guidance system, the target estimator plays an essential role. Besides the existing higher-order sliding-mode observer (HOSMO), a first-order linear observer (FOLO) is also proposed to estimate the target manoeuvre, and this is the major contribution of this paper. The closed-loop guidance system can be guaranteed to be uniformly ultimately bounded (UUB) in the presence of the FOLO. The comparative simulations are carried out to investigate the overall performance resulting from these two categories of observers. The results show that the guidance law with the proposed linear observer can achieve better comprehensive criteria for the amplitude of normalised acceleration and elevator deflection requirements. The reasons for the different levels of performance of these two observer-based methods are thoroughly investigated.

2

Optimal control strategy for marine SSP podded propulsion motor based on strong tracking-EPF

Yao W., Liu Y., Sun H., Zhang G., Zhang J., Zhou M., Sun M., Jiang D.

Polish Maritime Research

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2015

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S 1

4--9

EN

Aiming at the non-linearity of state equation and observation equation of SSP (Siemen Schottel Propulsor) propulsion motor, an improved particle filter algorithm based on strong tracking extent Kalman filter (ST-EKF) was presented, and it was imported into the marine SSP propulsion motor control system. The strong tracking filter was used to update particles in the new algorithm and produce importance densities. As a result, the problems of particle degeneracy and sample impoverishment were ameliorated, the propulsion motor states and the rotor resistance were estimated simultaneously using strong track filter (STF), and the tracking ability of marine SSP propulsion motor control system was improved. Simulation result shown that the improved EPF algorithm was not only improving the prediction accuracy of the motor states and the rotor resistance, but also it can satisfy the requirement of navigation in harbor. It had the better accuracy than EPF algorithm.

3

Preparation, Structure and Kinetic Analysis of the Thermal Behavior of Some Energetic Salts of 3-Hydrazino-4-amino-1,2,4-triazole

Wu J. T., Zhang J. G., Sun M., Yin X., Zhang T. L.

Central European Journal of Energetic Materials

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2013

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Vol. 10, no. 4

481--493

EN

As a key research objective for low melting explosives and propellants, energetic salts have received worldwide attention. 3-Hydrazino-4-amino-1,2,4triazole (HATr) is an important high-nitrogen compound (73.65% N) with good stability. This paper focuses on the energetic salts which were formed between HATr and picric acid (PA) or 2,4,6-trinitroresorcinol (TNR). Single crystals of HATr·PA and HATr·TNR·H2O were grown and their crystal structures determined at low temperature. They both belong to the monoclinic system, P21/n space group. The thermal characteristics of the two target salts were investigated using DSC and TG-DTG. In addition, the non-isothermal decomposition kinetics, heats of combustion and sensitivity have also been investigated. The detonation pressures (P) and detonation velocities (D) of the salts have been calculated using the K-J equations. The results indicated that both salts have certain potential applications as gunpowder and propellant materials.

4

Robust H∞ control for uncertain neutral time-delay systems with discrete and distributed delays

Sun M., Fu D.

Control and Cybernetics

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2011

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Vol. 40, no 1

25-38

EN

In this paper, the robust H∞ control problem is considered for uncertain neutral systems with discrete and distributed tirne delays. Some sumcient conditions on H∞, robust performance analysis are obtained in terms of linear matrix inequalities (LMIs) by using a descriptor model transformation of the system and by applying Park's inequality for bounding cross terms. Based on these conditions the state-feedback H∞ controller is designed. Numerical examples are included to illustrate the proposed method.

5

QoS-Driven Service Selection and Composition Using Quantitative Constraint Automata

Sun M., Arbab F.

Fundamenta Informaticae

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2009

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Vol. 95, nr 1

103-128

EN

Assuring Quality of Service (QoS) properties is critical in Service-Oriented Application (SOA) development. In this paper, we present an approach for specifying the QoS properties of services along multiple dimensions and selecting services for their composition in a way that optimizes the QoS of the result. We apply the integration of concerns paradigm to allow combined specification of QoS and functional properties by using Quantitative Constraint Automata, which integrate QoS aspects into service-oriented application development processes, mainly for service selection and composition.

6

Persistent bounded disturbance rejection for uncertain time-delay systems

Sun M., Jia Y.

Control and Cybernetics

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2009

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Vol. 38, no 3

593-607

EN

This paper considers the problem of persistent bounded disturbance rejection for a class of time-delay systems with parametric uncertainty by Lyapunov function and positively invariant set analysis method. Sufficient conditions for internal stability and L1-performance analysis are given in terms of linear matrix inequalities (LMIs). Based on the results, a simple approach to the design of a linear state-feedback controller is presented to stabilize robustly the uncertain time-delay systems and achieve a desired level of disturbance attenuation. All the obtained conditions are delay-dependent. A numerical example is included to illustrate the proposed method.