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Optimal maneuvering strategy of spacecraft evasion based on angles-only measurement and observability analysis

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Journal of Systems Engineering and Electronics 2023年第1期34卷 172-184页

作者： ZHANG Yijie wang Jiongqi HOU Bowen wang dayi CHEN Yuyun College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073China Beijing Institute of Spacecraft System Engineering Beijing 100190China School of Mathematics and Big Data Foshan UniversityFoshan 528000China

Spacecraft orbit evasion is an effective method to ensure space safety. In the spacecraft’s orbital plane, the space non-cooperate target with autonomous approaching to the spacecraft may have a dangerous rendezvous. To deal with this problem, an optimal maneuvering strategy based on the relative navigation observability degree is proposed with angles-only measurements. A maneuver evasion relative navigation model in the spacecraft’s orbital plane is constructed and the observability measurement criteria with process noise and measurement noise are defined based on the posterior Cramer-Rao lower bound. Further, the optimal maneuver evasion strategy in spacecraft’s orbital plane based on the observability is proposed. The strategy provides a new idea for spacecraft to evade safety threats autonomously. Compared with the spacecraft evasion problem based on the absolute navigation, more accurate evasion results can be obtained. The simulation indicates that this optimal strategy can weaken the system’s observability and reduce the state estimation accuracy of the non-cooperative target, making it impossible for the non-cooperative target to accurately approach the spacecraft.

关键词： rendezvous evasion orbit maneuver angles-only measurement observability degree posterior Cramer-Rao lower bound

Autonomous relative optical navigation based on unified modeling of external systematic errors

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Chinese Journal of Aeronautics 2024年第3期37卷 282-289页

作者： dayi wang Bowen SUN Maodeng LI Jiaxing LI Haiyin ZHOU Beijing Institute of Spacecraft System Engineering Beijing 100191China College of Sciences National University of Defense TechnologyChangsha 410073China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100191China

To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systematic errors of the optical camera is proposed,and autonomous relative optical navigation is *** camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can be established through specific attitude control and appropriate ***,the rotation error and the relative motion state are jointly estimated in an augmented Kalman filter *** with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity in that the estimated state dimension is ***,as demonstrated by numerical simulation,the estimation accuracy is improved significantly.

关键词： Unified model Systematic errors Optical navigation Observability analysis Calibration

Neuro-Optimal Guidance Control for Lunar Soft Landing

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Journal of Systems Engineering and Electronics 1999年第3期10卷 22-31页

作者： wang, dayi Li, Tieshou Yan, Hui Ma, Xingrui Harbin Inst of Technology Harbin China

Returning to moon has become a top topic recently. Many studies have shown that soft landing is a challenging problem in lunar exploration. The lunar soft landing in this paper begins from a 100 km circular lunar parking orbit. Once the landing area has been selected and it is time to deorbit for landing, a ΔV burn of 19.4 m/s is performed to establish a 100×15 km elliptical orbit. At perilune, the landing jets are ignited, and a propulsive landing is performed. A guidance and control scheme for lunar soft landing is proposed in the paper, which combines optimal theory with nonlinear neuro-control. Basically, an optimal nonlinear control law based on artificial neural network is presented, on the basis of the optimum trajectory from perilune to lunar surface in terms of Pontryagin's maximum principle according to the terminal boundary conditions and performance index. Therefore some optimal control laws can be carried out in the soft landing system due to the nonlinear mapping function of the neural network. The feasibility and validity of the control laws are verified in a simulation experiment.

关键词： Boundary conditions Computer simulation Control system analysis Control system synthesis Functions Lunar landing Lunar missions Maximum principle Neural networks Nonlinear control systems Optimal control systems Orbits

Stereo Vision-based Navigation and Guidance for Pinpoint Planetary Landing in Unknown Environments 36

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Stereo Vision-based Navigation and Guidance for Pinpoint Pla...

Fused Autonomous Navigation for Spacecrafts around Mars using Optical Measurements

第36届中国控制会议

作者： Chao Xu dayi wang Xiangyu Huang Beijing Institute of Control Engineering Science and Technology of Space Intelligent Control Laboratory

ISBN: (纸本)9781538629185

An autonomous navigation and guidance system based on stereo vision measurements is presented for pinpoint planetary landing in unknown ***,a relative navigation coordinate system is established based on the stereo vision measurements of unknown landmarks and the positions of the unknown landmarks in the relative navigation coordinate system are *** the position,velocity and attitude of the spacecraft expressed in the relative navigation coordinate system are ***,based on the estimated states of the spacecraft and the position of landing site calculated from its stereo vision measurements,the guidance command is computed by the Apollo guidance *** numerical simulation results for Mars landing indicate that the proposed navigation and guidance method is effective and feasible.

关键词： Navigation and guidance Stereo vision Pinpoint planetary landing Unknown environments

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Fused Autonomous Navigation for Spacecrafts around Mars usin...

Discrete-Time Integral Sliding Mode Fault-Tolerant Control with Uncertainties

新型导航技术及应用研讨会

作者： Maodeng Li dayi wang Xiangyu Huanga aScience and Technology on Space Intelligent Control and Laboratory Beijing Institute of Control Engineering

This paper focuses on the autonomous optical navigation problems for surrounded phase of Mars *** measurement equations using optical sensors are developed, and a fused navigation scheme is proposed based on state-vector fusion methods. In this scheme, each measurement equation is processed into individual Kalman filters to form local estimates, and a linear fusion rule is applied to fuse local estimates. The proposed fusion rule is derived from covariance-intersection algorithm to cope with unknown correlations and redundant information of local estimates. At last, the performance of all the navigation strategies are analyzed through numerical simulations.

关键词： Mars Exploration Autonomous Navigation Sensor Fusion Covariance Intersection Algorithm

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Discrete-Time Integral Sliding Mode Fault-Tolerant Control w...

Effect of Rapeseed Straw on Growth and Slaughter Performance of Sichuan White Goose

2015年中国智能自动化学术会议

作者： Duan Wenjie wang dayi Liu Chengrui Beijing Institute of Control Engineering

This paper researches fault-tolerant control for discrete-time multi-input multi-output(MIMO) linear time-invariant(LTI) systems with both matched and unmatched uncertainties.A discrete-time integral sliding mode(DISM) controller and an improved direct method for control allocation are proposed as the reconfigurable control ***-loop stability with matched and unmatched uncertainties for discrete-time MIMO LTI systems with DISM is studied,and the accuracy boundaries for are determined for the final states.A spacecraft model is simulated with multi-faults,efficiency factor inaccuracies,matched uncertainties,and unmatched uncertainties,which exemplifies our FTC scheme.

关键词： Discrete-time Integral sliding mode Fault-tolerant Uncertainties

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Animal Husbandry and Feed Science 2017年第6期9卷 360-362页

作者： Yang Ting Lei Zhengda Zhang Yishu Yu Zhiqiang wang dayi Sichuan Cereals and Oil Research Institute

[ Objective ] The paper was to study the effects of rapeseed straw on growth and slanghter performance of Sichuan white goose. [ Method ] Totally 400 3-day-old Sichuan white geese were randomly divided into four groups ; geese in control group were fed with the fundamental diet ; geese in group 1, group 2 and group 3 were fed with the fundamental diet containing 5%, 10% and 10% rapeseed straw instead of equal amount of wheat bran, respectively. The body weight and slaughter performance of Sichuan white geese in control group, group 1 and group 2 were determined at 10 weeks of age, while those in group 3 were determined at 14 weeks of age. [ Result] There was no significant difference in gross weight, slaughter weight, eviscerated weight with giblet, head weight, sole weight, wing weight, neck weight, muscular stomach weight and intestine indexes of 10-week-old white geese between group 1 and control group, and between group 2 and con- trol group （ P 〉 0.05 ） ; the live weight slightly decreased. The growth and slaughter performance of 14-week-old Sichuan white geese were significantly higher fllan that of 10-week-old geese （P 〈0.05）, with better meat and flavor, but relatively low average daily gain （P 〈0.05 ） ; there was no significant impact on muscular stomach pH and intestinal pH （P 〉 0.05 ）. [ Conclusion] Substituting partial wheat bran with rapeseed straw can satisfy the diet requirement of Sichuan white geese, but has no significant impact on its growth and slaughter performance （ P 〉 0.05）.

关键词： Rapeseed straw Sichuan white geese Growth performance Slaughter performance Meat quality

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脉冲星导航中最优脉冲星组合选取方法

中国空间科学技术 2011年第5期31卷 64-69页

作者：褚永辉王大轶黄翔宇北京控制工程研究所北京100190 空间智能控制技术重点实验室北京100190

分析了X射线脉冲星导航原理,发现脉冲星的位置和脉冲到达时间(Time of Arrival,TOA)的测量误差直接影响导航精度。为优选导航脉冲星组合,在误差协方差分析的基础上,提出了一种导航脉冲星组合优选方法。该方法分别定义了优选指标位置精... 详细信息

分析了X射线脉冲星导航原理,发现脉冲星的位置和脉冲到达时间(Time of Arrival,TOA)的测量误差直接影响导航精度。为优选导航脉冲星组合,在误差协方差分析的基础上,提出了一种导航脉冲星组合优选方法。该方法分别定义了优选指标位置精度因子(Positioning Dilution of Precision,PDOP)和脉冲星优选指标(Pulsars Select Criteria,PSC),不仅考虑了脉冲星空间位置分布,还考虑了测量噪声差异对导航误差的影响。最后以25颗信号品质较好的脉冲星为例,仿真验证了所提方法的有效性。

关键词： X射线脉冲星位置精度因子测量噪声脉冲星导航

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行星动力下降多约束最优反馈制导方法

宇航学报 2023年第8期44卷 1171-1182页

作者：张晓文王天舒王大轶李骥清华大学航天航空学院北京100084 北京控制工程研究所北京100190 北京空间飞行器总体设计部北京100094

为实现行星定点着陆,针对E制导和零控位移偏差/零控速度偏差(ZEM/ZEV)制导的不足,提出多约束下动力下降最优反馈制导方法。首先,在分析E制导性质的基础上,提出制导时长初值的高效选取方法和基于预测校正的优化方法,经少量迭代实现在推... 详细信息

为实现行星定点着陆,针对E制导和零控位移偏差/零控速度偏差(ZEM/ZEV)制导的不足,提出多约束下动力下降最优反馈制导方法。首先,在分析E制导性质的基础上,提出制导时长初值的高效选取方法和基于预测校正的优化方法,经少量迭代实现在推力范围受限且连续变推力约束下推进剂消耗接近最优。接着,提出基于碰撞规避时长和推力优化分配律的地平碰撞规避方法,并在此基础上利用坐标系旋转,给出满足下滑角约束的碰撞规避方法,显著提高碰撞规避能力和着陆点可见性。之后,提出匀速转动制导和基于预测校正的组合制导参数规划方法,使制导终端扩充满足加速度约束。最后,数学仿真表明新方法有效,多约束适应性强,计算量相对小,适合工程应用。

关键词：行星着陆动力下降最优反馈制导 E制导零控位移偏差/零控速度偏差