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排序方式: 共有878条查询结果,搜索用时 93 毫秒
871.
In this paper, the multi-missile cooperative guidance system is formulated as a general nonlinear multi-agent system. To save the limited communication resources, an adaptive eventtriggered optimal guidance law is proposed by designing a synchronization-error-driven triggering condition, which brings together the consensus control with Adaptive Dynamic Programming(ADP) technique. Then, the developed event-triggered distributed control law can be employed by finding an approximate solution of eve...  相似文献   
872.
873.
This paper deals with the problem of intercepting maneuvering targets with terminal angle constraints for missiles subjected to three-dimensional non-decoupling engagement geometry.To achieve the finite-time interception and satisfactory overload characteristics, a time varying sliding mode control methodology is developed based on a time base generator function. The main feature of the proposed guidance law guarantees the Line-of-Sight(LOS) angles to converge to small neighborhoods of the desir...  相似文献   
874.
针对拦截弹的抗干扰控制问题,设计了一种基于扩张状态观测器和快速滑模控制的三通道自动驾驶仪。首先建立考虑有界未知不确定性和外界干扰的拦截弹系统模型,构建扩张状态观测器对有界未知不确定性和外界干扰进行估计;在此基础上,根据自动驾驶仪系统特性,设计了一种快速滑模控制算法使得系统在受到有界未知不确定性和外界干扰的情况下仍然能精准快速跟踪指令信号,并基于李雅普诺夫函数证明了其稳定性。仿真结果验证了所设计控制算法的有效性。  相似文献   
875.
Space law education has an essential role in the space capacity building of a country because of its importance for human resources development in space law. Comparisons between Canada and China, the European Union and China and the United States of America (USA) and China in space law degree education, course, teaching methodology, institute and practice and communication platform are provided in an attempt to review some issues which exist within the Chinese space law educational system and to seek a better choice for China’s space law education reform. Chinese space law education has achieved noticeable progress over the past two decades. However, it is still limited in comparison to its counterparts in Europe and Northern America. The range of the space law degree education programmes and space-law-related courses is comparatively limited. A gap remains between space law education and practice in China. Chinese space law classes are still dominated by the teacher-centred teaching methodology, although several universities have some new teaching practices. The establishment of seven space law-related research institutes plays an increasingly important role in Chinese space law education, space law and policy research and legal advisory services for the Chinese government and non-governmental sectors. However, these institutes still have a long way to go in comparison with their counterparts in Europe and Northern America. While China has established domestic research platforms for space law communication through international cooperation, it does not provide space law practice platforms for space law education. While international space law does not provide a direct legal foundation for space law education in China, Chinese educational laws can lay a profound legal foundation for Chinese space law education. To promote its national expertise and capacity in space law, based on the three-pillar model and the experiences of its counterparts in North America and Europe, China should adopt a systematic and sustainable regime for its space law education.  相似文献   
876.
基于Backstepping的严格反馈极值搜索系统控制器设计   总被引:1,自引:1,他引:0       下载免费PDF全文
针对一类含不确定参数的严格反馈型极值搜索系统的控制问题,将极值搜索方法和反演(Backstepping)控制方法相结合,设计出系统状态的极值参考轨迹,利用 Backstepping控制方法逐步递推选取适当的 Lyapunov函数设计控制器和不确定参数自适应估计律,实现目标函数的极值搜索。仿真表明所提出控制器设计方法的有效性。  相似文献   
877.
878.
Aimed at complex distributed no-fly zones avoidance problems, a novel adaptive lateral reentry guidance algorithm is proposed. Firstly, by introducing the improved attractive and repulsive potential fields, an improved artificial potential field method is developed. Combined with the proposed judgment criterion for whether a no-fly zone has been avoided, the proposed improved artificial potential field method effectively solves the reference heading angle determination problem under the constrai...  相似文献   
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