Time filter

Source Type

Han F.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology
Proceedings of the International Astronautical Congress, IAC | Year: 2013

Since the constellation rotation is unobservable in the constellation autonomous orbit determination system only with inter-satellite range measurement, the errors grow with time. An approach of inter-satellite orientation observation is discussed, furthermore, an algorithm is proposed for long-term high accuracy constellation autonomous orbit determination with discontinuous inter-satellite orientation information. For a typical MEO constellation, the natural illumination for inter-satellite orientation observation is analyzed, with the result that the equivalent magnitude of target satellite is confirmed to be 13 to 15 degree. Furthermore, a scheme for inter-satellite orientation observation is presented. One central target satellite, two observing satellites are designed in each orbit plane, judging observable windows by target satellite photometry. Using this strategy, at least one set of orientation observation can be carried out at any time within the whole constellation. In order to distinguish the exact image point of the target satellite, an identification strategy is proposed, based on the high precision orientation of observer, high precision relative position between target satellite and observing satellite, star catalogue, and optical characteristic of the target satellite. Considering only discontinuous orientation information can be achieved, a self-adaptive filtering algorithm is proposed. Numerous simulation results demonstrate the effectiveness of the algorithm, which can modify the error caused by the constellation rotation, and then obtain the long-term high accuracy orbit information autonomously. Copyright© (2013) by the International Astronautical Federation. Source

Hou Y.,Harbin Institute of Technology | Hou Y.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology | Ma G.,Harbin Institute of Technology | Hou J.,China Aerospace Science and Technology Corporation
2013 25th Chinese Control and Decision Conference, CCDC 2013 | Year: 2013

Spacecraft tracking is a very important issue in the domain of spacecraft control. Traditional EKF method can not work well when the system noise is large and initial estimation is less accurate. In order to solve this, a novel central difference Kalman filter based on maxiam likehood posterior function is proposed in this paper. The second step of Kalman filter was modified in order to achieve better performance and a typical spacecraft tracking problem is given to show the advances the proposed method. © 2013 IEEE. Source

Zheng Z.,Shanghai Institute of Technology | Zheng Z.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology | Song S.-M.,Harbin Institute of Technology
Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering | Year: 2015

We investigate the cooperative attitude tracking control problem of multiple spacecraft in this paper, and propose novel control schemes using vector measurements. The nonlinear dynamics describing the attitude tracking control of formation are considered, and rotation matrix is adopted to avoid singularity and non-uniqueness. The cooperative attitude tracking controllers are proposed by using time-varying sliding mode control method and vector measurement results. The information of vector measurements can be obtained by using star trackers or Earth-horizon sensors. Especially, the proposed control algorithm is proven to be robust to external disturbance torque, measurement uncertainty, and time delays in communication links. Numerical simulations demonstrate the effectiveness of the proposed control schemes for cooperative attitude tracking. © IMechE 2015. Source

Fucheng L.,Shanghai Institute of Technology | Yuan D.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology
Proceedings of the International Astronautical Congress, IAC | Year: 2014

The design scheme of a kind of PnP fast-assembling satellite control demonstration system was proposed in this paper. The overall architecture of the system was introduced. The on-board computer simulator, the PnP modular and the host computer software were designed respectively. And the PnP time series of satellite control system devices was also described. The proposed PnP satellite scheme can extremely reduce the time of coordination, development and integrated test, cut down the cost of satellite development, and enhance the reliability of spacecraft, so as to lay a good technology foundation for the development of micro/nano satellite and operationally responsive spacecraft. Copyright © 2014 by the International Astronautical Federation. Source

Du W.,Huazhong University of Science and Technology | Liu Z.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology | Liu Z.,Harbin Institute of Technology | Zhang Y.,Shanghai Key Laboratory of Aerospace Intelligent Control Technology | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

In space rendezvous and docking missions, pose estimation of non-cooperative targets is challenging as priori information about motion and structure are unknown. The extraction and recognition are far more difficult conducted on a whole target. To solve this problem, a pose estimation method based on docking surface is proposed. The docking surfaces have more sophisticated structure with similar appearance among different countries than other surfaces. So docking surface is easy to automatically recognize or manually mark in images. In this paper, a control point representing mark information is chosen to assist with docking surface detection. The vertices of docking surface can be used to estimate pose. Firstly, binocular images are obtained by 3-D simulation technology. Then, a novel framework is proposed to detect edges of the docking surface in each image. Specifically, we detect lines in an image and group them according to the slopes. The control point is utilized to pick out the edges from the lines detected. Finally, the pose of the target is calculated by the four vertices of the docking surface. Simulation result shows that the position errors and attitude errors meet the requirement of pose estimation. The method provides a new solution for pose estimation of the non-cooperative target, and has potential significance for space rendezvous and docking technology. © 2015 SPIE. Source

Discover hidden collaborations