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Article
Publication date: 1 August 2005

Li Shuang, Cui Hutao and Cui Pingyuan

In order to succeed in landing asteroids, good accuracy autonomous navigation is absolutely necessary. Aims to describe a new autonomous navigation algorithm.

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Abstract

Purpose

In order to succeed in landing asteroids, good accuracy autonomous navigation is absolutely necessary. Aims to describe a new autonomous navigation algorithm.

Design/methodology/approach

First, gray images of asteroid surface are acquired by optical navigation camera, and nature feature points are detected and tracked autonomously. Second, the directional vector from spacecraft to the center of each feature point can be computed from the image coordinates in camera focal plane. Then, LIDAR/LRF is directed to three feature points and the distances from spacecraft to feature points are obtained. Last, the relative position vector from spacecraft to the target asteroid is reconstructed base on measurement outputs of navigation cameras and laser light radar (laser range finder).

Findings

Suppose the initial conditions presented in this paper, the autonomous optical navigation position error and velocity error are less than 1 m and 0.1 m/s, respectively; this navigation accuracy can satisfy the requirement of soft landing on asteroids.

Originality/value

Based on feature detection and tracking, an autonomous optical navigation scheme is brought out and the validity is confirmed by computer simulation.

Details

Aircraft Engineering and Aerospace Technology, vol. 77 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 10 July 2007

Pingyuan Cui and Fuzhan Yue

To provide an autonomous navigation system to endow lunar rovers with increased autonomy both for exploration achievement of scientific goals and for safe navigation.

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2610

Abstract

Purpose

To provide an autonomous navigation system to endow lunar rovers with increased autonomy both for exploration achievement of scientific goals and for safe navigation.

Design/methodology/approach

First, algorithm and technique of initial position determination of lunar rovers are introduced. Then, matched‐features set is build by multi steps of image processing such as feature detection, feature tracking and feature matching. Based on the analysis of the image processing error, a two‐stage estimation algorithm is used to estimate the motion, robust linear motion estimation is executed to estimate the motion initially and to reject the outliers, and Levenberg‐Marquardt non‐linear estimation is used to estimate the motion precisely. Next, a weighted ZSSD algorithm is presented to estimate the image disparities by analyzing the traditional ZSSD. Finally, a virtual simulation system is constructed using the development tool of open inventor, this simulation system can provide stereo images for simulations of stereo vision and motion estimation techniques, simulation results are provided and future research work is addressed in the end.

Findings

An autonomous navigation system is build based on stereo vision, the motion estimation algorithm and disparity estimation algorithm are developed.

Research limitations/implications

The field test will be done in the near future to valid the autonomous navigation algorithm presented in this paper.

Practical implications

A very useful source of information for graduate students and technical reference for researchers who work on lunar rovers.

Originality/value

In this paper, stereo vision‐based autonomous navigation techniques for lunar rovers are discussed, and an autonomous navigation scheme which based on stereo vision is presented, and the validity of all the algorithms involved is confirmed by simulations.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 22 May 2007

Yuan Ren, Pingyuan Cui and Enjie Luan

This paper aims to investigate, a new optimization algorithm for complex orbit transfer missions with low‐thrust propulsion system, which minimizes the drawbacks of…

Abstract

Purpose

This paper aims to investigate, a new optimization algorithm for complex orbit transfer missions with low‐thrust propulsion system, which minimizes the drawbacks of traditional optimization methods, such as bad convergence, difficulty of initial guesses and local optimality.

Design/methodology/approach

First, the trajectory optimization problem comes down to a nonlinear constraint parameter optimization by using the concept of traditional hybrid method. Then, one utilizes genetic algorithm (GA) to solve this parameter optimization problem after treating the constraints with the simulated annealing (SA) and random penalty function. Finally, one makes use of localized optimization to improve the precision of the final solutions.

Findings

This algorithm not only keeps the advantages of traditional hybrid method such as high precision and smooth solutions, but also inherits the merits of GA which could avoid initial guess work and obtain a globally optimal solution.

Research limitations/implications

Further, research is required to reduce the computational complexity when the transfer trajectory is very complex and/or has many adjustable variables.

Practical implications

By using this method, the globally optimal solutions of some complex missions, which could not be obtained by traditional method, could be found.

Originality/value

This method combines the GA with traditional hybrid method, and utilizes SA and random penalty functions to treat with constraints, and then gives out a super convergence way to find the globally optimal low‐thrust transfer orbit.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 6 September 2011

Cui Hutao, Cheng Xiaojun, Xu Rui and Cui Pingyuan

The purpose of this paper is to propose an attitude control algorithm for spacecraft with geometric constraints.

Abstract

Purpose

The purpose of this paper is to propose an attitude control algorithm for spacecraft with geometric constraints.

Design/methodology/approach

The geometric constraint is reformulated as a quadratic form when quaternion is used as attitude parameter, then the constraint is proved to be nonconvex and is further transformed to a convex one. By designing a new constraint formulation to satisfy the real constraint in the predictive horizon, the attitude control problem is reshaped to a convex planning problem which is based on receding horizon control.

Findings

The proposed algorithm is more effective in handling geometric constraints than previous research which used single step planning control.

Practical implications

With novel improvements to current methods for steering spacecraft from one attitude to another with geometric constraints, great attitude maneuver path can be achieved to protect instruments and meanwhile satisfy mission requirements.

Originality/value

The attitude control algorithm in this paper is designed especially for the satisfaction of geometric constraints in the process of attitude maneuver of spacecraft. By the application of this algorithm, the security of certain optical instruments, which is critical in an autonomous system, can be further assured.

Details

Aircraft Engineering and Aerospace Technology, vol. 83 no. 5
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 30 January 2007

Ren Yuan, Cui Pingyuan and Luan Enjie

This paper seeks to examine the development of the on‐board guidance law for multi‐revolutions orbit transfer spacecraft with low‐thrust propulsion systems.

Abstract

Purpose

This paper seeks to examine the development of the on‐board guidance law for multi‐revolutions orbit transfer spacecraft with low‐thrust propulsion systems.

Design/methodology/approach

In the research, first, a set of equinoctial elements is utilized to avoid the singularities in dynamical equation of classical orbit elements. A thruster switch law is derived by analyzing the efficiency of the changing of each orbit elements. Second, by using the theory of Lyapunov feedback control, analytic expressions of thrust angles are derived. Finally, the weights of the Lyapunov function are adjusted by hybrid genetic algorithm to improve the performance of the guidance law.

Findings

First, the dynamical equations of classical orbit elements are always singularity during the orbit transfer. By using modified equinoctial elements, these singularities could be avoided. Second, the trajectory is sensitive to the weights in Lyapunov function. With reasonable weights, the key parameters under the control of the guidance law presented in this paper are very close to that of optimal trajectory.

Research limitations/implications

In further research, some dynamical weights methods will be used in the control law to improve the performance index, and approach the optimal solution.

Practical implications

The guidance law presented in this paper could be easily used as an on‐board algorithm for the multi‐revolutions orbit transfer or stationkeeping. Furthermore, it could also be utilized as an initial design method for low‐thrust orbit transfer.

Originality/value

Providing a low‐thrust guidance law by combining the concept of Lyapunov feedback control with hybrid genetic algorithm. This method has a super convergence and a low‐computational cost.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 25 January 2008

Haibin Shang, Pingyuan Cui and Enjie Luan

The purpose of this paper is to study the application of the planetary aerogravity‐assist (AGA) technique to the interplanetary transfer mission with low‐thrust engine…

Abstract

Purpose

The purpose of this paper is to study the application of the planetary aerogravity‐assist (AGA) technique to the interplanetary transfer mission with low‐thrust engine, and the design and optimization approach of low‐thrust AGA trajectory.

Design/methodology/approach

In the research, the transfer trajectory with planetary AGA maneuver is analyzed first, the maximum atmospheric turn angle and the matching condition for AGA trajectory is derived out, which is the significant principle for AGA trajectory design and studies. Then, a design and optimization approach for interplanetary low‐thrust trajectory with AGA maneuver is developed. The complicated design problem is transformed into a parameter optimization problem with multiple nonlinear constraints by using calculus of variations and the matching condition associated with AGA trajectory. Furthermore, since the optimization problem is very sensitive to the launch date and AGA maneuver parameters, three ordinal sub‐problems are reformulated to reduce the sensitivity. Finally, a direct/indirect hybrid approach is utilized to solve these sub‐problems.

Findings

The planetary AGA maneuver is feasible and effective in decreasing the propellant consumption and flight time for interplanetary low‐thrust mission and provides better performance than pure planetary gravity assist. Moreover, the proposed approach is effective to design and optimize the low‐thrust transfer mission with AGA maneuver.

Research limitations/implications

In further research, some simple preliminary design approaches for interplanetary low‐thrust trajectory with AGA maneuver are required to developed, which can provide a good initial conjecture for a hybrid optimization algorithm.

Originality/value

The paper provides the matching condition for interplanetary AGA transfer trajectory by analyzing some characteristics of planetary AGA maneuver, and presents an effective approach to design and optimize interplanetary low‐thrust AGA trajectory.

Details

Aircraft Engineering and Aerospace Technology, vol. 80 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 15 March 2013

Zunhui Zhao, Haibin Shang, Pingyuan Cui and Xiangyu Huang

The purpose of this paper is to present a solution space searching method to study the initial design of interplanetary low thrust gravity assist trajectory.

Abstract

Purpose

The purpose of this paper is to present a solution space searching method to study the initial design of interplanetary low thrust gravity assist trajectory.

Design/methodology/approach

For reducing the complexity and nonlinearity of the initial design problem, a sixth degree inverse polynomial shape based approach is brought. Then some improvements are provided for solving the parameters in the shape function and a quasi‐lambert solver is brought through the shape based method, the thrust profile can be generated under the given time of flight, boundary states including positions and velocities for low thrust phase. Combining gravity assist model, the problem is summarized and an improved pruning technique is used for searching the feasible solution space for low thrust gravity assist trajectory.

Findings

Using the solution space searching method, the feasible solution region would be generated under the given mission condition. The treatment about gravity assist demonstrates more accurate than previous method. Also another advantage is that the searching method can be used to design different types of mission trajectory, including flyby and rendezvous trajectories.

Practical implications

The method can be used as an efficient approach to search the feasible region for the complex low thrust gravity assist trajectory, and it can provide appropriate initial guesses for the low thrust gravity assist trajectory in mission design phase.

Originality/value

Feasible solution space would be obtained through the searching method. The quasi‐Lambert solver in the paper is found under the shape‐based method and relative improvement, and it shows its availability during the searching process. Through mission trajectory design, the effectiveness of the method is shown.

Details

Aircraft Engineering and Aerospace Technology, vol. 85 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

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