Project Articles

    Theme Articles on "Dynamics and Control of Flight to Near-Earth Celestial Bodies"

    Default Latest Most Read
    Please wait a minute...
    For Selected: Toggle Thumbnails
    MODEL AND ANALYSIS OF ΔDOR TRACKING BY CHINA DSN WITH TT&C MODE
    Tang Geshi, Han Songtao, Cao Jianfeng, Chen Lüe, Ren Tianpeng, Wang Mei
    Chinese Journal of Theoretical and Applied Mechani    2015, 47 (1): 24-30.   DOI: 10.6052/0459-1879-14-328
    Abstract605)   HTML1)    PDF(pc) (3975KB)(871)       Save

    Very long baseline interferometry (VLBI) can provide accurate plane of sky measurement of spacecraft. Based on the first implementation of interferometric tracking in CE'3 project by China DSN (Deep Space Network), this paper describes modeling interferometric tracking with TT&C mode. Earth based stations keeps pointing to the spacecraft while it is in view of antenna. So interruption of TT&C signal can be eliminated, which is unavoidable with traditional short-scan working mode. Compared with high accuracy orbit ephemeris, delay observable error is less than 1ns which corresponds to an angular accuracy of about 97nrad (37m uncertainty at the Earth-Moon distance). Accuracy of delay observable is in the same order with CVN baseline which has the similar configuration.

    Reference | Related Articles | Metrics
    MARS GRAVITY CAPTURE DYNAMIC MODEL AND ERROR ANALYSIS
    Fang Baodong, Wu Meiping, Zhang Wei
    Chinese Journal of Theoretical and Applied Mechani    2015, 47 (1): 15-23.   DOI: 10.6052/0459-1879-14-327
    Abstract807)   HTML6)    PDF(pc) (1664KB)(1168)       Save

    Mars orbit capture is a one and only opportunity for Mars probes and the key factor to determine whether the mission is successful. Starting with the constrained three-body problem, equations for calculating the Mars gravity sphere, influence sphere and Hill sphere are derived. Their property and applicability are discussed. Based on the definition and physical significance of influence sphere, an engineering definition of capture phase is proposed. The orbital dynamic model was built inside the influence sphere and the error sources that may affect the accuracy of capture orbit are presented. Finally, the influences on perigee and apogee of the capture orbit caused by the position and velocity navigation error, engine thrust error and timing errors are analyzed through Monte Carlo simulations. The limit exceed possibility caused by different error sources are also discussed and the dominating sources is pointed out. The result can be used as a reference for the orbit capture implementation of future Chinese Mars orbiters.

    Reference | Related Articles | Metrics
    Cited: Baidu(1)
    AERODYNAMIC CHARACTERISTICS MEASSUREMENT OF MARS VEHICLES DURING ENTRY FLIGHT
    Yang Lei, Hou Yanze, Zuo Guang, Liu Yan, Guo Bin
    Chinese Journal of Theoretical and Applied Mechani    2015, 47 (1): 8-14.   DOI: 10.6052/0459-1879-14-331
    Abstract835)   HTML2)    PDF(pc) (1926KB)(1041)       Save

    Performing aerodynamic measurement can acquire a mounts of data during Mars entry exploration. This work benefits for aerodynamic characteristics confirmation and improves key flight performance, such as landing accuracy. In this study, an aerodynamic measurement system scheme is proposed based on trajectory reconstruction and flush air data system. Angle of attack and angle of side slip are measured by output error method with measured trajectory; dynamical pressure is measured via Flush air data system and least square optimal estimation. By simulation, it shows that the proposed measurement scheme has high measure accuracy, and dynamical pressure accuracy is 1%, and angle of attack and angle of side slip accuracy are improved more than one time. This study is helpful for aerodynamic measurement of deep-space exploration entry flight, such as Mars exploration entry flight.

    Reference | Related Articles | Metrics
    A SURVEY OF GRANULAR DYNAMICS MODELING AND SIMULATION METHODS FOR RUBBLE-PILE ASTEROIDS
    Zhang Yun, Li Junfeng
    Chinese Journal of Theoretical and Applied Mechani    2015, 47 (1): 1-7.   DOI: 10.6052/0459-1879-14-329
    Abstract746)   HTML2)    PDF(pc) (174KB)(1484)       Save

    Asteroid exploration will be the spotlight of the research in aerospace science in upcoming decade. The present data indicates that most of the asteroids are loosely consolidated "rubble pile" structures, which have zero tensile strength and are easy to be disrupted by external force produced by exploration missions. Therefore, to guarantee the execution of the asteroid exploration mission, it is essential to build the dynamics model of the asteroid and explore the asteroid evolution's interaction effect. Based on the upcoming China's asteroid exploration mission, the research status and development of granular dynamics is reviewed and analyzed. Then, the dynamical modeling and numerical simulation methods of rubble-pile asteroids are recapitulated in detail, according to the state of art of international relating researches. Finally, the key technical problems of the modeling of rubble-pile asteroids in asteroid exploration mission are proposed.

    Reference | Related Articles | Metrics
       2015, 47 (1): 0-0.  
    Abstract317)   HTML2)    PDF(pc) (50KB)(641)       Save
    Related Articles | Metrics