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131.
In this paper, a novel multi-frame track-before-detect algorithm is proposed, which is based on root label clustering to reduce the high computational complexity arising by observation area expansion and clutter/noise density increase. A criterion of track extrapolation is used to construct state transition set, root label is marked by state transition set to obtain the distribution information of multiple targets in measurement space, then measurement plots of multi-frame are divided into sever... 相似文献
132.
基于飞行-推力一体化思想提出了一种针对搭载超燃冲压发动机的吸气式高超声速飞行器速度通道的状态/输入约束自适应鲁棒保性能安全控制方案。首先根据超燃冲压发动机的机理分析与计算流体动力模型数据,建立了安全子系统与性能子系统面向控制的仿射非线性模型。之后基于障碍Lyapunov理论与动态面设计方法设计了一套安全子系统状态约束控制器,从理论上保证了飞行器在跟踪指令的全过程中,发动机相关状态不会触碰安全边界,并结合自适应技术与辅助系统提高了该控制系统的鲁棒性。针对性能子系统设计了一套鲁棒自抗扰控制器,达到“保证安全的前提下不折损性能”的目的。仿真结果表明所设计的控制系统可以在保障安全的同时达到预想的性能,并显著放宽了超燃冲压发动机对飞行器飞行姿态的约束,保证了高超声速飞行器的机动灵活性。 相似文献
133.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(5):2155-2174
This paper addresses the design of the terminal phase maneuver of the booster landing in the presence of initial deviations and uncertainties. The primary purpose of this study is to evaluate the effectiveness of the vectorized high order expansions method to extract commands and near-optimal trajectory, while the accurate satisfaction of the terminal conditions is of great importance. After reviewing high order expansions methods, the Vectorized High Order Expansions method is briefly discussed. Then, the solution for the booster landing problem is extracted up to the third order. To study the solution quality in the presence of uncertainties, mass, density, and gravity are assumed to be constant in extracting the 3rd order solution. The assumptions however are eliminated in the simulations, and the effectiveness of high order expansions solution is studied subjectively and numerically in the presence of initial deviations and uncertainties. After implementing simulations and considering different assumptions, it will be shown that the 3rd order solution holds a desirable quality in accurately satisfying final conditions in presence of uncertainties and initial deviations and provides far better results than the 1st order solution. Moreover, in this paper, a novel method is proposed for online updating, and the performance and effect of this modification are studied using simulations. Reviewing the results of the 3rd order solution combined with the online update strategy, it becomes clear that the implementation of the online update significantly reduces landing point errors and improves the performance of the high order method. Furthermore, the study compares the performance of this strategy with the well-known state-dependent Riccati equation method to better evaluate the effectiveness of the proposed approach. 相似文献
134.
In recent years, Chinese Long March(LM) launchers have experienced several launch failures, most of which occurred in their propulsion systems, and this paper studies Autonomous Mission Reconstruction(AMRC) technology to alleviate losses due to these failures. The status of the techniques related to AMRC, including trajectory and mission planning, guidance methods,and fault tolerant technologies, are reviewed, and their features are compared, which reflect the challenges faced by AMRC technology... 相似文献
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为了解决目前机器人路径规划中时效性低、避障解算量大的问题,借鉴直流电路中理想电感元件两端电压能够从感抗状态恢复到稳定状态的现象,提出了一种利用机器人状态检测量对机器人状态实时检测,从而实现避障的机器人路径规划算法.首先对绕行单个固定障碍物的机器人进行深入分析,然后采用状态叠加的方法,生成任意位置多障碍物同时存在的避障路径.同时对斥力系数进行改进,以确保机器人能够有效到达目标点.为了验证算法在多障碍物环境下的路径规划能力,进行了数值仿真模拟实验.仿真结果表明,使用该算法规划机器人路径时,能够在避免局部极小值点和目标不可达问题的前提下,在较短时间内规划出机器人由起始点到目标点的路径. 相似文献