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Zhu Z.,Northwestern Polytechnical University | Zhu Z.,National Key Laboratory of Aerospace Flight Dynamics | Ma J.,Northwestern Polytechnical University | Ma J.,National Key Laboratory of Aerospace Flight Dynamics | And 2 more authors.
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2016

For the approaching operations with intensity coupling between position and attitudes, precise synchronization control of relative translation and rotation is one of the essentials to be solved. Traditionally, translation and rotation motion are modeled and controlled separately, in which the coupling between relative position and attitudes is ignored, so the control period is long and the synchronization cannot be guaranteed. This paper investigates the synchronization control problem of spacecraft relative motion. A six-degree-of-freedom relative motion model is proposed using the dual-number representation of screw theory, which can not only describe the coupling effect between the translational movement and the rotational one, but also make the model of translation and rotation in the same style to the benefits of designing controller easy. The causes of couple forming are presented after analyzing the coupling term of the relative motion model. A synchronization error constructed by the relative translation and rotation is introduced. A synchronization control law is designed based on nonlinear feedback to eliminate the error, and its stability is proved by Lyapunov methods. Choosing the final approaching phase of docking and rendezvous to make numerical simulation, the results demonstrate the validity of the proposed method by comparing with PD controller. Meanwhile, it is proved that the proposed method can achieve synchronous convergence of the attitudes and orbit control, which has important implications for the required attitudes and orbit synchronization operations. © 2016, Press of Chinese Journal of Aeronautics. All right reserved.


Cui J.-F.,National Key Laboratory of Aerospace Flight Dynamics | Zhang K.,National Key Laboratory of Aerospace Flight Dynamics | Lu M.-B.,National Key Laboratory of Aerospace Flight Dynamics
Kongzhi yu Juece/Control and Decision | Year: 2015

The computational load of traditional tensor product distributed compensation(TPDC) control method explodes with the dimensionality of the parameter vector of the parameter-varying state-space model. So it is difficult for the traditional method to be applied in the high dimensional LPV system. Therefore, a TPDC control method based on uniform design is proposed, which method utilizes the uniform design to acquire the discretized tensor of the LPV system. As a consequence, the discretized data have little correlation with the dimensionality of the parameter vector. The simulation results show that the control method can reduce the computational load effectively without degradation of the control performance. ©, 2015, Northeast University. All right reserved.


Deng Y.,Northwestern Polytechnical University | Deng Y.,National Key Laboratory of Aerospace Flight Dynamics | Li C.,China Aerospace Science and Technology Corporation | Wang Z.,Northwestern Polytechnical University | Wang Z.,National Key Laboratory of Aerospace Flight Dynamics
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2015

An adapted iterative guidance algorithm is researched for the orbit transfer mission of spacecraft. Based on the traditional iterative guidance method, we directly found the optimal control model on the geocentric inertial frame, use the orient vector of the thrust as the control variable to adapt for the significantly change of attitude angel, found the boundary conditions by using the target orbital elements directly as the terminal constraints, obtain the relationship between the accuracy of the solutions of the constraint equations and the injection accuracy, and then present a concise and effective iterative guidance algorithm using orbital elements as terminal constraints for spacecraft orbit transfer. Numerical simulations have demonstrated the effectiveness and better adaptability than the traditional method. ©, 2015, AAAS Press of Chinese Society of Aeronautics and Astronautics. All right reserved.


Wang Z.G.,Northwestern Polytechnical University | Wang Z.G.,National Key Laboratory of Aerospace Flight Dynamics | Zhang N.,Northwestern Polytechnical University | Zhang N.,National Key Laboratory of Aerospace Flight Dynamics
Applied Mechanics and Materials | Year: 2013

Since the traditional parabola trajectory is prone to be head off, wavy trajectory has the flight characteristics of defense penetration ability and increasing range. On the basis of flight characteristics of wavy trajectory missile, a method for flight program angle was designed. A specific formula was given. An optimization model was established. A conjugate gradient optimizing algorithm was used to solve the model and the result is compared with the former trajectory. It shows that optimized wavy trajectory can prove the feasibility of increasing range and valid defense penetration ability. © (2013) Trans Tech Publications, Switzerland.


Wang Z.G.,Northwestern Polytechnical University | Wang Z.G.,National Key Laboratory of Aerospace Flight Dynamics | Li W.,Northwestern Polytechnical University | Li W.,National Key Laboratory of Aerospace Flight Dynamics
Applied Mechanics and Materials | Year: 2013

On the basis of dual-spin projectile multi-body characteristics, the angular motion model is established in the quasi-body coordinates. Through linearization, the system dynamic stability factor and gyroscopic stability factor are obtained by differential equations characteristic roots. There is also informative to compare the dual-spin projectile gyroscopic stability factor to the conventional rigid projectile results. The comparison can be viewed where the influence of the spin rates ration γf/γa and the ratio of inertia moments Cf/Caon the ratio Sg/Sy g of the gyroscopic stability factors. Through the numerical example, the dual-spin projectile has a similar stability to that of a conventional rigid projectile, and the curves of the relationship between the ratio Sg/Sy g of the gyroscopic stability factors with the ratio of spin rates γf/γa and the ratio of inertia moments Cf/Ca are got by simulation. © (2013) Trans Tech Publications, Switzerland.


Wang Z.G.,Northwestern Polytechnical University | Wang Z.G.,National Key Laboratory of Aerospace Flight Dynamics | Deng Y.F.,Northwestern Polytechnical University | Deng Y.F.,National Key Laboratory of Aerospace Flight Dynamics
Applied Mechanics and Materials | Year: 2013

The problem of spacecraft attitude estimation utilizing star sensors and gyros is considered in this paper. Since the errors of the quaternion outputs of star sensors projected on the direction along the optical axis is higher than the other two directions, a novel method to increase the estimation accuracy of the attitude filter is presented, by producing observation vectors along the direction of the light axes, which are composed of a couple of quaternion outputs from different star sensors. The proposed algorithm is validated and proved more precise by numerical simulations. © (2013) Trans Tech Publications, Switzerland.


Wang Z.G.,Northwestern Polytechnical University | Wang Z.G.,National Key Laboratory of Aerospace Flight Dynamics | Yan S.,Northwestern Polytechnical University | Yan S.,National Key Laboratory of Aerospace Flight Dynamics
Applied Mechanics and Materials | Year: 2013

The problem of low accuracy for classic guidance law is considered in this paper. Based on the mature theory used in missiles, this paper presents an integrated guidance law for reentry vehicles. At the initial stage of reentry flight, standard trajectory guidance law is employed, and then converts to 3dof proportional guidance law when this vehicle is close to the target. Simulation results are provided to demonstrate the accuracy of the proposed integrated guidance law. © (2013) Trans Tech Publications, Switzerland.


Yan X.-D.,Northwestern Polytechnical University | Yan X.-D.,National Key Laboratory of Aerospace Flight Dynamics | Wang Z.,Northwestern Polytechnical University
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2013

It's an effective way to improve the guidance adaptability for hypersonic glide vehicle (HGV) by applying trajectory planning. First, the target plane coordinate frame was defined. Then, taking the coordinate frame as the reference coordinate frame, dynamic equations with the normalized energy as independent variable were deduced, which have the advantages of fixed integral interval, and cross-range and longitudinal range could be denoted by the equation states. Based on the equations, longitudinal trajectory planning method was put forward as well as lateral trajectory planning method. With the combination of above methods and the trajectory of lateral curvature, a three-dimensional trajectory planning method has been implemented. It is shown that the proposed method can fulfill trajectory planning for HGV rapidly and accurately.


Wang Z.G.,Northwestern Polytechnical University | Wang Z.G.,National Key Laboratory of Aerospace Flight Dynamics | Zhang Z.N.,Northwestern Polytechnical University | Zhang Z.N.,National Key Laboratory of Aerospace Flight Dynamics
Applied Mechanics and Materials | Year: 2013

Modeling and simulation method of unsteady aerodynamics on morphing wings were investigated. The Unsteady Vortex Lattice Method is employed to model the unsteady aerodynamics of 3-D potential flow field surrounding the wing. An UVLM computer code was then developed and validated for numerical simulation. A morphing wing which changes its dihedral angle with constant angular velocity was investigated by the code, and the lift, induced drag, and pitching moment coefficients' time histories were obtained. The results show that the UVLM code is an effective tool for simulations of unsteady aerodynamics on morphing wings. © (2013) Trans Tech Publications, Switzerland.


Yan X.-D.,Northwestern Polytechnical University | Yan X.-D.,National Key Laboratory of Aerospace Flight Dynamics | Jia X.-J.,Northwestern Polytechnical University | Lv S.,Northwestern Polytechnical University
Guti Huojian Jishu/Journal of Solid Rocket Technology | Year: 2013

Rocket based combined cycle (RBCC) powered vehicles generally climb with constant dynamic pressure at ascent stage in order to provide an optimal or steady condition for the propulsion system. An algebraic equation of height and velocity for constant dynamic pressure climbing was derived. The algebraic equation was used to plan and generate the reference trajectory. Then, a guidance law tracking the reference trajectory was derived via feedback linearization method. Based on the above, the guidance method of constant dynamic pressure climbing for ascent stage of RBCC powered vehicle was implemented. The simulation results show that the method is able to generate the command of attack angle in real-time and complete constant dynamic pressure climbing accurately. Furthermore, the method provides an ascent trajectory design and guidance method for air breathing aerospace vehicle.

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