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61.
基于滤噪微分器的四旋翼飞行器控制 总被引:1,自引:0,他引:1
在飞行器的控制中, 角速率反馈可以提高控制系统的动态特性, 但速率陀螺价格昂贵, 且随运行时间的增加其性能会不断下降. 对此本文提出了一种基于滤噪微分器的四旋翼飞行器滑模变结构控制律. 该控制律使用的反馈信号仅由角度传感器得到, 而无需角速率传感器. 控制律中的角速率信息由王新华等设计的有限时间收敛的微分器得到. 本文通过数学证明, 给出了当测量信号中含有噪声时该微分器的理论跟踪误差上界. 仿真以及对四旋翼飞行器滚转姿态的控制实验验证了微分器的抑制噪声作用和控制算法可行性. 相似文献
62.
63.
基于跟踪微分器的离散滑模控制器 总被引:1,自引:0,他引:1
利用跟踪微分器设计了一种新的离散滑模控制器,可以从不连续的指令信号中合理提取连续信号及微分信号,且不需要利用线性外推的方法预测指令信号下一时刻的值及其微分.与基于趋近律的离散滑模控制器进行的对比仿真表明,所设计的控制器在保持传统滑模控制固有强鲁棒性的同时,控制器的输出几乎不存在抖振现象,而且在跟踪不连续的指令信号时,系统表现出良好的动态品质. 相似文献
64.
针对防空导弹垂直发射姿态调转时的快速性要求,研究了快速姿态调转的控制问题.首先基于一类多输入多输出高阶非线性系统的Teminal(终态)滑模变结构控制方法,对垂直发射防空导弹的滚动和俯仰、偏航通道所呈现的非线性、强耦合性进行了分析,并设计了一种新型滑模控制器.控制器设计方案消除了滑模控制的到达阶段,系统的初始状态始终保持在滑模面上,确保了系统的全局鲁棒性和稳定性,且能在有限且可控时间内使跟踪误差趋近于零.最后通过数字仿真验证了系统在不确定因素情况下具有强鲁棒性和适应性,可用于防空导弹短时间姿态调转控制. 相似文献
65.
为了使系统满足品质要求并对不确定因素具有较强的鲁棒性,采用滑模控制方法。建立被控对象T-S模糊模型。针对系统状态不完全可测特点,采用迭代线性矩阵不等式方法,利用输出信息构造滑模面。根据系统品质要求,采用参数鲁棒设计方法,配置所需极点,确定相应在参数空间的映射关系。应用平行分布补偿算法,根据映射产生的参数样本训练T-S模糊控制器,实现等效控制律。在此基础上应用高增益方法设计切换控制律,保证系统对满足匹配条件的不确定因素具有较理想的自适应性。最后,直升机模型的仿真结果表明,方法具有很好的控制效果。 相似文献
66.
针对一般的具有时变且界未知的非线性不确定性的单输入多输出非线性系统,提出一种自适应滑模跟踪控制器的框架.在该框架内,系统的时变且界未知的非线性不确定性可以通过函数逼近技术(FAT)表示成为一组正交基函数序列的组合,并通过滑模控制技术和直接Lyapunov方法获得基函数系数的更新律以及对不确定性逼近误差的在线自适应补偿,从而得到自适应的滑模控制律.所提出的基于函数逼近技术的自适应滑模跟踪控制策略在直流电机跟踪控制系统实验装置上进行了实际控制实验,并进行了性能的对比与分析. 相似文献
67.
Mehmet Önder Efe 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(1):23-29
This paper presents an approach to improve the performance of intelligent sliding model control achieved by the use of a fundamental
constituent of soft computing, named Adaptive Linear Element (ADALINE). The proposed scheme is based on the fractional calculus.
A previously considered tuning scheme is revised according to the rules of fractional order differintegration. After a comparison
with the integer order counterpart, it is seen that the control system with the proposed adaptation scheme provides (1) better
tracking performance, (2) suppression of undesired drifts in parameter evolution and (3) a very high degree of robustness
and insensitivity to disturbances. The claims are justified through some simulations utilizing the dynamic model of a two
degrees of freedom (DOF) direct drive robot arm and overall, the contribution of the paper is to introduce the fractional
order calculus into a robust and nonlinear control problem with some outperforming features that are absent when the integer
order differintegration operators are adopted. 相似文献
68.
ZHANG Xiao-yu 《通讯和计算机》2009,6(1):53-60
Sliding mode-like fuzzy logic control (SMFC) algorithm for nonlinear systems is presented in this paper. Firstly dead zone parameters of sliding mode control (SMC) are selftuned by proper adaptive laws and then combined into fuzzy logic system (FLS) to compose the opportune fuzzy logic control (FLC), which is equivalent to the predesigned SMC controller with self-tuning parameters. Robustness and invariance to the uncertainties of the closed-loop systems are improved and chattering of the SMC is eliminated. Finally simulation results of numerical examples show that the proposed control algorithm is efficient and feasible. 相似文献
69.
Daewon Lee H. Jin Kim Shankar Sastry 《International Journal of Control, Automation and Systems》2009,7(3):419-428
This paper presents two types of nonlinear controllers for an autonomous quadrotor helicopter. One type, a feedback linearization
controller involves high-order derivative terms and turns out to be quite sensitive to sensor noise as well as modeling uncertainty.
The second type involves a new approach to an adaptive sliding mode controller using input augmentation in order to account
for the underactuated property of the helicopter, sensor noise, and uncertainty without using control inputs of large magnitude.
The sliding mode controller performs very well under noisy conditions, and adaptation can effectively estimate uncertainty
such as ground effects.
Recommended by Editorial Board member Hyo-Choong Bang under the direction of Editor Hyun Seok Yang. This work was supported
by the Korea Research Foundation Grant (MOEHRD) KRF-2005-204-D00002, the Korea Science and Engineering Foundation(KOSEF) grant
funded by the Korea government(MOST) R0A-2007-000-10017-0 and Engineering Research Institute at Seoul National University.
Daewon Lee received the B.S. degree in Mechanical and Aerospace Engineering from Seoul National University (SNU), Seoul, Korea, in 2005,
where he is currently working toward a Ph.D. degree in Mechanical and Aerospace Engineering. He has been a member of the UAV
research team at SNU since 2005. His research interests include applications of nonlinear control and vision-based control
of UAV.
H. Jin Kim received the B.S. degree from Korea Advanced Institute of Technology (KAIST) in 1995, and the M.S. and Ph.D. degrees in Mechanical
Engineering from University of California, Berkeley in 1999 and 2001, respectively. From 2002–2004, she was a Postdoctoral
Researcher and Lecturer in Electrical Engineering and Computer Science (EECS), University of California, Berkeley (UC Berkeley).
From 2004–2009, she was an Assistant Professor in the School of in Mechanical and Aerospace Engineering at Seoul National
University (SNU), Seoul, Korea, where she is currently an Associate Professor. Her research interests include applications
of nonlinear control theory and artificial intelligence for robotics, motion planning algorithms.
Shankar Sastry received the B.Tech. degree from the Indian Institute of Technology, Bombay, in 1977, and the M.S. degree in EECS, the M.A.
degree in mathematics, and the Ph.D. degree in EECS from UC Berkeley, in 1979, 1980, and 1981, respectively. He is currently
Dean of the College of Engineering at UC Berkeley. He was formerly the Director of the Center for Information Technology Research
in the Interest of Society (CITRIS). He served as Chair of the EECS Department from January, 2001 through June 2004. In 2000,
he served as Director of the Information Technology Office at DARPA. From 1996 to 1999, he was the Director of the Electronics
Research Laboratory at Berkeley (an organized research unit on the Berkeley campus conducting research in computer sciences
and all aspects of electrical engineering). He is the NEC Distinguished Professor of Electrical Engineering and Computer Sciences
and holds faculty appointments in the Departments of Bioengineering, EECS and Mechanical Engineering. Prior to joining the
EECS faculty in 1983 he was a Professor with the Massachusetts Institute of Technology (MIT), Cambridge. He is a member of
the National Academy of Engineering and Fellow of the IEEE. 相似文献
70.
In this article, a distributed leader-follower consensus approach is developed for a class of high-order unknown nonlinear dynamic multi-agent systems (MASs). Because every agent of the MAS contains multiple state variables, the existing consensus methods are not completely applicable for it. In order to find the qualified consensus protocol for this high-order MAS, sliding mode mechanism can be naturally considered for designing the consensus control because it can manage multiple state variables with the help of a constructed hyperplane. To this consensus control design, the sliding mode term is composed of all tracking error variables. Since the method does not require the switching control term around sliding surface, it can avoid the chattering phenomenon, which exits in most of the published sliding mode controls (SMCs). Furthermore, to handle the unknown nonlinear dynamic problem, the adaptive approximation strategy is implemented by employing fuzzy logic system (FLS). In the light of Lyapunov stability analysis, it is demonstrated that the proposed control approach can accomplish the consensus tasks. Finally, a numerical example is implemented to further show the desired results. 相似文献