http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
한성익 한국생산제조학회 2009 한국생산제조학회지 Vol.18 No.1
In this paper, a tracking control problem for a mechanical servo system with nonlinear dynamic friction is treated. The nonlinear friction model contains directly immeasurable friction state and the uncertainty caused by incomplete modeling and variations of its parameter. In order to provide the efficient solution to these control problems, we propose a hybrid control scheme, which consists of a robust friction state observer, a RFNN estimator and an approximation error estimator with sliding mode control. A sliding mode controller and a robust friction state observer is firstly designed to estimate the unknown internal state of the LuGre friction model. Next, a RFNN estimator is introduced to approximate the unknown lumped friction uncertainty. Finally, an adaptive approximation error estimator is designed to compensate the approximation error of the RFNN estimator. Some simulations and experiments on the mechanical servo system composed of ball-screw and DC servo motor are presented. Results demonstrate the remarkable performance of the proposed control scheme.
한성익 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.2
This study investigates a new fractional-order nonsingular terminal sliding mode control (FTSMC) leveraging a finite-time extended state observer, a simpler prescribed control, and hybrid grey wolf optimization (GWO) combined with whale optimization algorithm (WOA) for manipulator systems. The new FTSMC system is based on an improved fractional-order terminal sliding surface. Initially, the study experimentally optimizes the dynamic parameters and gains of the controller and the observer with the help of the newly developed GWO-WOA technique. As the next step, the uncertainties including optimization error and external disturbances are estimated by the finite-time extended state observer designed using the sliding mode dynamics. Experimental results of GWOWOA optimization and joint position tracking for a self-designed articulated manipulator prove the efficacy of the proposed control scheme.
순환형 신경망을 이용한 적응형 능동소음제어시스템의 성능 향상에 대한 연구
한성익,이태오,여대연,이권순,Han, Song-Ik,Lee, Tae-Oh,Yeo, Dae-Yeon,Lee, Kwon-Soon 한국정보통신학회 2010 한국정보통신학회논문지 Vol.14 No.8
순환형 신경망을 이용한 적응형 능동소음 제어시스템의 소음저감 성능을 개선한다. 능동소음제어에 가장 많이 사용되고 있는 FXLMS는 단순하고 계산 부담이 적지만 FIR 선형필터에 기반을 둔 필터링 방법이어서 주 경로 또는 2차 경로의 비선형특성에 취약한 단점이 있다. 본 연구에서는 이러한 비선형 특성과 불확실성에 대해 강인한 특성을 갖는 순환형 신경망 필터링 기법을 개발하여 능동소음 제어시스템의 소음 저감 성능을 개선함을 시뮬레이션을 통해 보인다. The performance of noise attenuation of the adaptive active noise control algorithm is improved using the recurrent neural network. The FXLMS that has been frequently used in the active noise control is simple and has low computational load, but this method is weak to nonlinearity of the main or secondary path since it is based on the FIR linear filter method. In this paper, the recurrent neural network filter has been developed and applied to improvement of the active noise attenuation by simulation.
Robust adaptive deadzone and friction compensation of robot manipulator using RWCMAC network
한성익,이권순,Min Gyu Park,이장명 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.6
A robust adaptive compensation scheme is presented for compensation of asymmetric deadzone, dynamic friction and uncertainty in the direct-drive robot manipulator. Simple estimation laws are derived to build observers for estimation of deadzone and friction based on the LuGre friction model. A model-free RWCMAC controller to mimic the ideal control law is employed to overcome some shortcomings of the traditional model-based adaptive controller, which requires information on the robots dynamics in advance. The Lyapunov stability analysis yields the adaptive laws of the RWCMAC network as well as observers of deadzone and friction. Furthermore, the stability and optimal convergence speed of the learning rates of the RWCMAC is also guaranteed by employing the fully informed particle swarm (FIPS) algorithm. Robust tracking performance of the proposed control schemes is verified by simulations of direct-drive robots with deadzone in joint input torque, joint dynamic friction and uncertainty.
한성익 한국정밀공학회 2003 International Journal of Precision Engineering and Vol.4 No.5
Tracking control schemes on the precise mechanical system in presence of nonlinear dynamic friction is proposed. A nonlinear dynamic friction is regarded as the bristle friction model to compensate for effects of friction. The conventional SMC method often shows poor tracking performance in high-precision position tracking application since it cannot completely compensate for the friction effect below a certain precision level. Thus to improve the precise position tracking performance, we propose the SMC method combined with the disturbance observer having tunable transient performance. Then this control scheme has the high precise tracking performance as well as a good transient response when it is compared with the conventional SMC method and the similar types of observers. The experiment on the XY ball-screw drive system with the nonlinear dynamic friction confirms the feasibility of the proposed control scheme.
한성익,이진우,이태오,이권순 제어로봇시스템학회 2009 제어로봇시스템학회 국내학술대회 논문집 Vol.2009 No.9
In this article, we develop a hybrid control scheme of a dynamic structured learning recurrent fuzzy neural network (DRFN) and a dynamic friction observer. The DRFN controller with the adaptive dynamic friction observer based on the LuGre friction is designed to position the servo system and estimate the friction parameters and a directly immeasurable friction state variable. Next, a reconstructed error estimator is also designed to give additional robustness to the control system under the presence of the model uncertainty. A proposed composite control scheme is applied to the position tracking control of the servo system.
Barrier Lyapunov function-based model-free constraint position control for mechanical systems
한성익,하현욱,이장명 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.7
In this article, a motion constraint control scheme is presented for mechanical systems without a modeling process by introducing a barrier Lyapunov function technique and adaptive estimation laws. The transformed error and filtered error surfaces are defined to constrain the motion tracking error in the prescribed boundary layers. Unknown parameters of mechanical systems are estimated using adaptive laws derived from the Lyapunov function. Then, robust control used the conventional sliding mode control, which give rise to excessive chattering, is changed to finite time-based control to alleviate undesirable chattering in the control action and to ensure finite-time error convergence. Finally, the constraint controller from the barrier Lyapunov function is designed and applied to the constraint of the position tracking error of the mechanical system. Two experimental examples for the XY table and articulated manipulator are shown to evaluate the proposed control scheme.
비선형 동적시스템에 대한 비선형 미분 외란관측기를 이용한 유한시간 Dynamic Surface 제어기 설계
한성익 제어·로봇·시스템학회 2019 제어·로봇·시스템학회 논문지 Vol.25 No.8
This study proposes a finite-time dynamic surface control (DSC) combined with a nonlinear differentiator disturbanceobserver for nonlinear systems, in which dynamics are partially known. The nonlinear differentiator disturbance observer, virtualstabilizing controllers, and final controller were designed based on finite-time convergent theorem via the recursive steps in conventionalDSC system. In conclusion, the study results show that the filtered output error due to the first-order filter in a conventionalDSC, which is the source of controller design complexity and stability, can be bypassed; this is because stability is provided by afinite-time Lyapunov function comprised of newly defined variables instead of the tracking error variables used in conventionalDSCs. Thus, the controller design procedure and stability analysis can be more intuitive than those of a conventional DSC. Anotherimportant study result is the design of a nonlinear differentiator disturbance observer for nonlinear systems to estimate uncertainty infinite-time. The study shows that very competitive results can be achieved using the proposed method, as shown by the simulationresults for an articulated manipulator system.