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There are 22 papers published in subject: since this site started. |
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1. Research on multi-UAV focused area cooperative search based on MTSP | |||
Xu Jianfeng,Zhuang Yufeng | |||
Aviation 17 March 2022 | |||
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Abstract:This paper takes the multi-UAV area search problem as the background, addresses the multi-UAV collaborative search track planning task assignment problem in which the target location is known in the environment but the number of targets is large and the target location is randomly dispersed, combines the multi-traveler MTSP problem, establishes a multi-UAV focused collaborative search track planning task assignment model, and designs a GA algorithm based on the target location coding multi-crossing operator multivariable operator and an improved SA algorithm for multi-UAV collaborative focused search track planning, both algorithms have better solution effects, and the SA algorithm has better optimized solution effects than the GA algorithm. | |||
TO cite this article:Xu Jianfeng,Zhuang Yufeng. Research on multi-UAV focused area cooperative search based on MTSP[OL].[17 March 2022] http://en.paper.edu.cn/en_releasepaper/content/4757044 |
2. A Method of Autonomous Optical Navigation with Radio Beacon Auxiliary Information at the Approach Phase of Deep Space Exploration | |||
Zhu Shengying,Jing Yan | |||
Aviation 23 May 2016 | |||
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Abstract:According to task requests of deep space exploration approach phase such as autonomy, real-time and so on, we do a research into the problem of autonomous navigation at this approach phase and put forward an autonomous navigation project which makes use of radio beacon and navigation camera to determine relative position and velocity of the spacecraft. The radio beacon can measure its distance to the spacecraft and the navigation camera can acquire the line-of-sight vector to the target. With kalman filter we can get the spacecraft's state information. The observability degree of the navigation system is increased by importing a new observation. In order to verify the performance of this autonomous navigation system, simulink tests based on the practical data of Deep Impact mission are carried on. The results show that the presented method can not only meet navigation requests of approach phase but also gain the navigation system observability degree | |||
TO cite this article:Zhu Shengying,Jing Yan. A Method of Autonomous Optical Navigation with Radio Beacon Auxiliary Information at the Approach Phase of Deep Space Exploration[OL].[23 May 2016] http://en.paper.edu.cn/en_releasepaper/content/4692757 |
3. Modeling and Simulation of Stochastic Optimal Control for Gliding Extended Range Rocket Projectile Attitude | |||
Bian Wei-wei,LI Yan,XIN Zhen-fang,CHANG Si-jiang | |||
Aviation 30 November 2015 | |||
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Abstract:An optimal control method for nonlinear stochastic systems is proposed to overcome the influence of various disturbance factors and to improve the control effect. Considering the general control principle of rocket projectile flight process, a differential form of attitude dynamics model is established. Taking the attack angle and the yaw angle as observation variables and rudder angles as control variables, the state equations, the quadratic cost function and the control law are presented. The detailed expression of the adjoint function is put forward. The optimal filter is designed based on the Riccati equation. Control parameter is designed and simulation analysis is carried out by taking gliding starting control point as the feature point. The simulation results show that the attitude controller system responds quickly and has good control quality. | |||
TO cite this article:Bian Wei-wei,LI Yan,XIN Zhen-fang, et al. Modeling and Simulation of Stochastic Optimal Control for Gliding Extended Range Rocket Projectile Attitude[OL].[30 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4667119 |
4. Transient probabilistic analysis for turbine blade-tip radial clearance with multi-component and multi-physics fields based on DCERSM | |||
Guo Ruichen,Fei Chengwei,Bai Guangchen | |||
Aviation 20 November 2015 | |||
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Abstract:Against the background of the probabilistic analysis for High Pressure Turbine (HPT) Blade-tip Radial Running Clearance (BRRC) to achieve the high-performance and high-reliability of aeroengine, Distributed Collaborative Extremum Response Surface Method (DCERSM) was proposed for the dynamic probabilistic analysis of complex turbomachinery on the foundation of quadratic polynomials response surface model. On the basis of deeply investigating Extremum Response Surface method (ERSM), the mathematical model of DCERSM was established based on quadratic polynomial function. As illustrated in BRRC transient probabilistic analysis with multiple components and multi-physics fields based on DCERSM, blade-tip radial static clearance δ=1.82 mm is advisable synthetically considering the reliability and working efficiency of gas turbine. The reliability, distribution characteristics and failure probability of BRRC are obtained. Besides, rotational speed ω and gas temperature T are the most important factors and expansivity coefficients and surface coefficients of heat transfer show also important influence on BRRC variation. Through the comparison of three methods (DCERSM, ERSM, Monte Carlo method), it is demonstrated that DCERSM reshapes the possibility of complex turbomachinery probabilistic analysis and improves computing efficiency while preserving the accuracy. DCERSM offers a useful insight for BRRC dynamic reliability design and optimization with multi-object and multi-discipline. The efforts of this study also enrich the theory and method of mechanical reliability design. | |||
TO cite this article:Guo Ruichen,Fei Chengwei,Bai Guangchen. Transient probabilistic analysis for turbine blade-tip radial clearance with multi-component and multi-physics fields based on DCERSM[J]. |
5. A robust sequence image matching algorithm for solving flight position and heading | |||
Ru Jiangtao,Leng Xuefei,Wu Songsen,Mao Xingyun,Gong Zhe | |||
Aviation 19 September 2015 | |||
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Abstract:As for the transformations of translation and rotation exist between sequence images in the image matching navigation system, it is hoped that the algorithm can simultaneously solve the position and heading parameters. Therefore, an algorithm for sequence image matching based on Harris corner and modified hausdorff distance was proposed. In this method, the coordinates of the corners are described in both polar coordinates and Descartes coordinates. Considering the rotational invariance of radius set in polar coordinates, Hausdorff distance is used to match radius sets between sequence images. Then, the rotation angle and the translation distance will be calculated. Experimental analysis has been carried out for the influence of different Gauss noise and the number of Harris corner. Results show that images can still be matched with rotation angle of ${0^ circ }$, ${60^ circ }$, and ${90^ circ }$ under Gauss white noise with 0.01 variance while the position error is less than one pixel, heading error is less than 5 degrees, and matching time is about 4 seconds. The algorithm has robustness and can meet the requirements of real-time and accuracy of sequence image matching for navigation system. | |||
TO cite this article:Ru Jiangtao,Leng Xuefei,Wu Songsen, et al. A robust sequence image matching algorithm for solving flight position and heading[OL].[19 September 2015] http://en.paper.edu.cn/en_releasepaper/content/4654929 |
6. Deep Space Quantum Communication and Navigation | |||
CUI Pingyuan,YU Zhengshi | |||
Aviation 02 April 2014 | |||
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Abstract:At present, deep space navigation primarily depends on the Deep Space Network. To meet the challenges of future Solar and Galaxy explorations, this paper proposes the concept of deep space quantum communication and navigation. Such a communication and navigation network with high speed, broad bandwidth, and high accuracy will be constructed based on the quantum communication mechanism and relay communication architecture. This communication and navigation network may support the basic scheme of deep space quantum communication and navigation. | |||
TO cite this article:CUI Pingyuan,YU Zhengshi. Deep Space Quantum Communication and Navigation[OL].[ 2 April 2014] http://en.paper.edu.cn/en_releasepaper/content/4592155 |
7. Experimental investigations of cutting parameters influence on cutting forces and specific cutting energy in milling of GH4169G | |||
ZHOU Xu,WU Baohai,ZHENG Chengyu,LUO Ming | |||
Aviation 25 December 2013 | |||
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Abstract:In this paper study, an attempt has been made to investigate the effects of cutting parameters (cutting speed, feed per tooth, radial depth of cut, axial depth of cut) on cutting forces and specific cutting energy in milling of GH4169G using carbide tool. The single factor experiments and multi-factor orthogonal experiments were conducted. The results show a slight reduction in cutting forces with increasing of cutting speed from 70m/min to 120m/min. The specific cutting energy is almost constant with increasing of cutting speed from 70m/min to 120m/min. The cutting speed has great influence on specific cutting energy in milling GH4169G super alloy. Optimized cutting parameters (cutting speed, feed per tooth, radial depth of cut, axial depth of cut) based on range analysis for milling GH4169G are also given in the paper, the results can be directly used in industry. | |||
TO cite this article:ZHOU Xu,WU Baohai,ZHENG Chengyu, et al. Experimental investigations of cutting parameters influence on cutting forces and specific cutting energy in milling of GH4169G[OL].[25 December 2013] http://en.paper.edu.cn/en_releasepaper/content/4578306 |
8. Optimal ZEM/ZEV Feedback Guidance for Mars Powered Descent Phase | |||
ZHOU Liuyu,,XIA Yuanqing | |||
Aviation 07 November 2013 | |||
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Abstract:This paper applies the zero-effort-miss (ZEM) and zero-effort-velocity (ZEV) optimal feedback guidance algorithm to the Mars powered descent problem. Detailed descriptions have been given to this algorithm. The main advantage of this optimal guidance law is that it can not only meet the final position and velocity requirement at the same time, but also be fuel-optimal. For future Mars landing mission, the thrust-limited engine is most likely to be used. The optimal final time will be studied and determined by simulation which can minimize the fuel usage while ensuring precision landing and no-subsurface constraints. And the optimal sliding-mode guidance(OSG) which is a modification of optimal guidance law(OGL) will also be discussed and compared with the pure optimal guidance law for the Mars powered descent phase. Monte Carlos are run to test the robustness and reliability of the two algorithms which show that the two algorithms can achieve precise landing perfectly and have nearly identical performance in robustness and reliability. | |||
TO cite this article: ZHOU Liuyu,,XIA Yuanqing. Optimal ZEM/ZEV Feedback Guidance for Mars Powered Descent Phase[OL].[ 7 November 2013] http://en.paper.edu.cn/en_releasepaper/content/4568642 |
9. Mars Entry Guidance Based on Predictor-Corrector Algorithm | |||
ZHOU Liuyu,XIAYuanqing,CHEN Rongfang,CUI Pingyuan | |||
Aviation 11 October 2013 | |||
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Abstract:This paper addresses the development and evaluation of the numerical predictor-corrector algorithm for the Mars entry guidance.The requirement of future Mars missions is to enable pinpoint and high elevation Mars landing.There are two main entry guidance algorithms: guidance using a reference trajectory and guidance using predictor-corrector.Guidance algorithm that tracks the reference trajectory during entry, has some degree of model-independence and does not require fast on-board computation, but it is sensitive to initial conditions.However, the predictor-corrector algorithm can be less sensitive to initial dispersions, but needs fast on-board computation.Detailed descriptions of predictor-corrector algorithm, lateral control logic and heading alignment are given and an improved predictor-corrector algorithm is provided to shorten the on-board computational time. Simulation results show that this entry guidance algorithm demonstrates reliable and robust performance in situations with high uncertainties. | |||
TO cite this article:ZHOU Liuyu,XIAYuanqing,CHEN Rongfang, et al. Mars Entry Guidance Based on Predictor-Corrector Algorithm[OL].[11 October 2013] http://en.paper.edu.cn/en_releasepaper/content/4563676 |
10. Unified Redundant Patterns for Star Identification | |||
Ji Feilong,Jiang Jie,Wei Xinguo | |||
Aviation 13 August 2013 | |||
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Abstract:Star pattern identification algorithms have employed widely to identify observed stars by star trackers which require reliabilities and adaptivities of algorithms. However, the noises especially the number of stars in field of view (FOV) are still serious problems for primitive star pattern algorithms. A novel algorithm of unified redundant patterns, which are combined with novel redundant neighbor patterns and redundant radial patterns, for star trackers in the "lost in space" mode is presented. Since neighbor patterns and radial patterns describe two different distributions, the distributions between neighbor stars each other and the distributions in the radial direction respectively, and constructed with similar redundant coding solution, they are combined to unified redundant patterns and stored by binary bit strings which reduce memory requirement of on-board database significantly. For the pattern redundancies and combinations, as well as similar score measurement applying patterns synthetically other than multiple-step match, consequently, the proposed algorithm is robust to the star positional noise, magnitude noise and performs still well when sparse stars are in FOV. When evaluated with synthesized star images, our algorithm can obtain identification rates of 99.14% (positional noise is 0.4 pixels). When there are only 4 stars in FOV, the algorithm can still obtain identification rate of 77.03%, much higher than the other star pattern identification algorithms. | |||
TO cite this article:Ji Feilong,Jiang Jie,Wei Xinguo. Unified Redundant Patterns for Star Identification[OL].[13 August 2013] http://en.paper.edu.cn/en_releasepaper/content/4554923 |
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