Yanchao Yue^{1, *}, Tangbing Chen¹, Lingling Zhang¹, Moustafa Abdelsalam¹, Josephine Musanyufu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 259-272, 2020, DOI:10.32604/cmes.2020.07218

Abstract Based on wave interference, a methodology to realize the total transmission phenomenon of SH0 waves is proposed in this paper. After a systematical theoretical investigation, an exact frequency of a flat plate consisting of another medium with finite length, is obtained, which is furthermore exemplified by the finite element method. This frequency is the same as the classical Fabry-Perot condition and dependent on the thickness of the material. It has been revealed that an SH0 wave, with its wavelength equal to twice of the length of another medium, can totally transmit across the medium without reflection. Especially when the impedance… More >

Yanbin Zhao^{1, *}, Bin Du², Shuang Li²

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 235-257, 2020, DOI:10.32604/cmes.2020.08070

Abstract Satellite observation schedule is investigated in this paper. A mission planning algorithm of task clustering is proposed to improve the observation efficiency of agile satellite. The newly developed method can make the satellite observe more targets and therefore save observation resources. First, for the densely distributed target points, a pre-processing scheme based on task clustering is proposed. The target points are clustered according to the distance condition. Second, the local observation path is generated by Tabu algorithm in the inner layer of cluster regions. Third, considering the scatter and cluster sets, the global observation path is obtained by adopting Tabu… More >

Baichun Gong¹, Shuang Li^{1, *}, Lili Zheng², Jinglang Feng³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 221-234, 2020, DOI:10.32604/cmes.2020.07769

Abstract A closed-form solution to the angles-only initial relative orbit determination (IROD) problem for space rendezvous with non-cooperated target is developed, where a method of hybrid dynamics with the concept of virtual formation is introduced to analytically solve the problem. Emphasis is placed on developing the solution based on hybrid dynamics (i.e., Clohessy-Wiltshire equations and two-body dynamics), obtaining formation geometries that produce relative orbit state observability, and deriving the approximate analytic error covariance for the IROD solution. A standard Monte Carlo simulation system based on two-body dynamics is used to verify the feasibility and evaluate the performance proposed algorithms. The sensitivity… More >

Baichun Gong¹, Chenglong He^{2, *}, Degang Zhang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 207-219, 2020, DOI:10.32604/cmes.2020.08616

Abstract Aimed at the problem of final translation of space rendezvous for the applications such as docking, inspection and tracking, optimal straight-line guidance algorithm based on pulse/continuous low-thrust in the context of Clohessy-Wiltshire dynamics is proposed. Two modes of guidance strategy: varying-speed and fixed-speed approaching scheme for V-bar and R-bar approach by using constant/finite low-thrust propulsion respectively are studied, and the corresponding fuel-optimal conditions are obtained. Numerical simulation is conducted to verify and test the proposed algorithms. The results show that there is generally no different between the fuel consumptions by using the two different approaching modes for V-bar case. However,… More >

Xianghao Hou^{1, *}, Gang Qiao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 175-205, 2020, DOI:10.32604/cmes.2020.08452

Abstract To study the parameter estimating effects of a free-floating tumbling space target, the extended Kalman filter (EKF) scheme is utilized with different high-nonlinear translational and rotational coupled kinematic & dynamic models on the LIDAR measurements. Applying the aforementioned models and measurements results in the situation where one single state can be estimated differently with varying accuracies since the EKFs based on different models have different observabilities. In the proposed EKFs, the traditional quaternions based kinematics and dynamics and the dual vector quaternions (DVQ) based kinematics and dynamics are used for the modeling of the relative motions between a chaser satellite… More >

Junfeng Zhao^{1, 2}, Weiming Feng¹, Jianping Yuan^{2, 3, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 149-174, 2020, DOI:10.32604/cmes.2020.07504

Abstract Recent studies of the space debris environment in Low Earth Orbit (LEO) have shown that the critical density of space debris has been reached in certain regions. The Active Debris Removal (ADR) mission, to mitigate the space debris density and stabilize the space debris environment, has been considered as a most effective method. In this paper, a novel two-level optimization strategy for multi-debris removal mission in LEO is proposed, which includes the low-level and high-level optimization process. To improve the overall performance of the multi-debris active removal mission and obtain multiple Pareto-optimal solutions, the ADR mission is seen as a… More >

Kai Liu^{1, 2}, Zheng Hou^{2, *}, Zhiyong She², Jian Guo²

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 131-148, 2020, DOI:10.32604/cmes.2020.08124

Abstract This paper studies the reentry attitude tracking control problem for hypersonic vehicles (HSV) equipped with reaction control systems (RCS) and aerodynamic surfaces. The attitude dynamical model of the hypersonic vehicles is established, and the simplified longitudinal and lateral dynamic models are obtained, respectively. Then, the compound control allocation strategy is provided and the model predictive controller is designed for the pitch channel. Furthermore, considering the complicated jet interaction effect of HSV during RCS is working, an improved model predictive control approach is presented by introducing the online parameter estimation of the jet interaction coefficient for dealing with the uncertainty and… More >

Qiancai Ma¹, Fengjie Gao², Yang Wang³, Qiuxiong Gou³, Liangyu Zhao^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 109-130, 2020, DOI:10.32604/cmes.2020.08109

Abstract Combining adaptive theory with an advanced second-order sliding mode control algorithm, a roll stabilization controller with aerodynamic disturbance and actuator failure consideration for spinning flight vehicles is proposed in this paper. The presented controller is summarized as an “observer-controller” system. More specifically, an adaptive second-order sliding mode observer is presented to select the proper design parameters and estimate the knowledge of aerodynamic disturbance and actuator failure, while the proposed roll stabilization control scheme can drive both roll angle and rotation rate smoothly converge to the desired value. Theoretical analysis and numerical simulation results demonstrate the effectiveness of the proposed controller. More >

Renyong Zhang¹, Caisheng Wei^{2, *}, Zeyang Yin^{3, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 89-107, 2020, DOI:10.32604/cmes.2020.07985

Abstract This paper investigates a novel quasi fixed-time orbit tracking control method for spacecraft around an asteroid in the presence of uncertain dynamics and unknown uncertainties. To quantitatively characterize the transient and steady-state responses of orbit tracking error system, a continuous performance function is devised via using a quartic polynomial. Then, integrating backstepping control technique and barrier Lyapunov function leads to a quasi fixed-time convergent orbit tracking controller without using any fractional state information and symbolic functions. Finally, two groups of illustrative examples are employed to test the effectiveness of the proposed orbit control method. More >

Xin Wang^{1, 2, *}, Xiaokui Yue^{1, 2}, Haowei Wen^{1, 2}, Jianping Yuan^{1, 2}

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 61-87, 2020, DOI:10.32604/cmes.2020.06871

Abstract In this paper, a hybrid passive/active vibration (HPAV) controller of a loosely connected spacecraft consisting of a servicing satellite, a target and an X-shape structure isolator is first proposed to suppress vibrations of the system when subjected to the impulsive external excitations during the on-orbit missions. The passive dynamic response of the combined system can be adjusted appropriately to achieve the desired vibration isolation performance by tuning the structural parameters of the bio-inspired X-shape structure. Moreover, the adaptive control design through dynamic scaling technique is selected as the active component to maintain high vibration isolation performance in the presence of… More >