A fault tolerant control methodology based adaptive sliding mode(ASM) backstepping is proposed for near space vehicle(NSV) attitude control system under engine faults. The proposed scheme combined adaptive backsteppin...A fault tolerant control methodology based adaptive sliding mode(ASM) backstepping is proposed for near space vehicle(NSV) attitude control system under engine faults. The proposed scheme combined adaptive backstepping with the sliding mode control strategy could guarantee the system’s stability and track desired signals under external disturbances and engine faults. Firstly, attitude mode description and the engine faulty model are given. Secondly, a nominal control law is designed.Thirdly, a sliding mode observer is given later in order to estimate both the information of engine faults and external disturbances. An adaptive sliding mode technology based on the previous nominal control law is developed via updating faulty parameters. Finally,analyze the system’s fault-tolerant performance and reliability through experiment simulation, which verifies the proposed design of fault-tolerant control can tolerate engine faults, as well as the strong robustness for external disturbance.展开更多
针对口形特征点定位的准确性问题,提出一种基于HASM(hierarchical active shape model)的口形轮廓定位方法,采用不等步长、不等角度建模策略和口形聚类策略,构建局部纹理模型作为特征点搜索依据,并利用马氏距离选取最佳定位点.试验结...针对口形特征点定位的准确性问题,提出一种基于HASM(hierarchical active shape model)的口形轮廓定位方法,采用不等步长、不等角度建模策略和口形聚类策略,构建局部纹理模型作为特征点搜索依据,并利用马氏距离选取最佳定位点.试验结果表明,HASM模型的口形特征点定位方法使内唇定位和闭口口形定位的准确率达到90%以上.展开更多
基金supported by the National Natural Science Foundation of China(6140321061601228+3 种基金61603191)the Natural Science Foundation of Jiangsu(BK20161021)the Nanjing University of Posts and Telecommunications Science Foundation(NY214173)the Open Program of Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing(3DL201607)
文摘A fault tolerant control methodology based adaptive sliding mode(ASM) backstepping is proposed for near space vehicle(NSV) attitude control system under engine faults. The proposed scheme combined adaptive backstepping with the sliding mode control strategy could guarantee the system’s stability and track desired signals under external disturbances and engine faults. Firstly, attitude mode description and the engine faulty model are given. Secondly, a nominal control law is designed.Thirdly, a sliding mode observer is given later in order to estimate both the information of engine faults and external disturbances. An adaptive sliding mode technology based on the previous nominal control law is developed via updating faulty parameters. Finally,analyze the system’s fault-tolerant performance and reliability through experiment simulation, which verifies the proposed design of fault-tolerant control can tolerate engine faults, as well as the strong robustness for external disturbance.
文摘针对口形特征点定位的准确性问题,提出一种基于HASM(hierarchical active shape model)的口形轮廓定位方法,采用不等步长、不等角度建模策略和口形聚类策略,构建局部纹理模型作为特征点搜索依据,并利用马氏距离选取最佳定位点.试验结果表明,HASM模型的口形特征点定位方法使内唇定位和闭口口形定位的准确率达到90%以上.