비선형 시스템에서의 백스테핑 기법을 이용한 새로운 퍼지 외란 관측기 설계

백재호(Jaeho Baek),이희진(Heejin Lee),박민용(Mignon Park) 大韓電子工學會 2010 電子工學會論文誌-SC (System and control) Vol.47 No.2

본 논문은 불특정한 외란을 가진 비선형 시스템에서의 백스테핑 기법을 이용한 새로운 퍼지 외란 관측기 설계 방법을 제안한다. 먼저, 퍼지 논리 시스템을 이용하여 불특정한 외란을 관측하기 위한 관측 입력을 가진 퍼지 외란 관측기를 설계한다. 제안된 외란 관측기가 불특정한 외란을 관측하는 것을 증명하기 위해 외란 관측 오차 시스템을 도입한다. 백스테핑 기법을 도입하여 각 단계에서의 퍼지 외란 관측기의 파라미터 적응 규칙과 외란 관측기의 관측 입력을 유도하고 외란 오차 시스템의 안정성을 증명한다. 제안된 외란 관측기의 명확성을 증명하기 위해서 모의 실험 예제들을 제공한다. This paper is proposed a novel fuzzy disturbance observer based on backstepping method for nonlinear systems with unknown disturbance. Using fuzzy logic systems, a fuzzy disturbance observer with the disturbance observation input is introduced for unknown disturbance. To guarantee that the proposed disturbance observer estimates the unknown disturbance, the disturbance observation error dynamic system is employed. Under the framework of the backstepping design, the fuzzy disturbance observer is constructed recursively and an adaptive laws and the disturbance observation input are derived. Numerical examples are given to demonstrate the validity of our proposed disturbance observer for nonlinear systems.

Disturbance Observer-based Trajectory Following Control of Robot Manipulators

Mohamadreza Homayounzade,Amir Khademhosseini 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.1

Robotic manipulators are usually subject to different types of disturbances. If the effects of such disturbancesare not taken into account, it can lead to unsatisfactory tracking performance of the robot and may evendestabilize the robot control system. In this paper a novel nonlinear disturbance observer-based controller is designedfor robotic manipulators. Previous disturbance observer-based controllers which are designed for roboticsystems undergo the restricting assumption that the external disturbance is constant. In this paper a novel two-stageprocedure is proposed to design a disturbance observer that improves disturbance attenuation ability of current disturbanceobserver-based controllers. The proposed method can cope with non-constant disturbance. Furthermore,it is shown that even for the fast time varying disturbance, the controller achieves satisfactory tracking performance. The proposed controller guarantees semi-global asymptotic position and velocity tracking and moreover, removesrestrictions of previous studies on the number of degrees of freedom (DOFs), joint types, and manipulator configuration. The effectiveness of the proposed method is verified against different types of external disturbance appliedon the robot manipulator and the results are compared with the results of previous methods. Furthermore, the resultssupport the theoretical conclusions.

A Novel Disturbance Observer using Adaptive Observation and Time Delay Estimation in Discrete Time Systems

Sung-Hwan Kim,Kyung-Soo Kim,Soohyun Kim 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

In the note, a novel disturbance observer capable of both abrupt disturbances and general disturbance having bounded bandwidth is proposed. Initiated from an adaptive disturbance observation, we enhanced the estimation property to cope with abrupt disturbance and bounded bandwidth disturbances. The generalized form of disturbance observer is derived on the state space. To estimate the abrupt disturbance efficiently, time delay estimation is combined with adaptive estimation method. In addition, for a class of linear systems, its potential applicability will be demonstrated by a numerical simulation.

미지의 상수 오프셋을 갖는 삼각함수 외란 추정을 위한 모델기반 저차 외란 관측기 설계

이초원(Cho-Won Lee),손영익(Young Ik Son) 대한전기학회 2016 전기학회논문지 Vol.65 No.4

In practical control systems differences between nominal and real systems arise from internal uncertainties and/or external disturbances. This paper presents a model-based low-order disturbance observer for a sinusoidal disturbance with unknown constant offset. By using the disturbance model of a biased harmonic signal, the proposed method can successfully estimate the biased sinusoidal disturbance with unknown amplitude and phase but known frequency. At the first stage of the observer design, a model-based disturbance observer is designed when all the system states are measurable. Next, a sufficient condition is presented for the proposed observer to estimate the sinusoidal disturbance with a minimal-order additional dynamics using only output measurement. Comparative computer simulations are performed to test the performance of the proposed method. The simulation results show the enhanced performance of the proposed disturbance observer.

Reinterpretation of Disturbance Observer as an Add-on Controller

Hyung-Tae Seo,Kyung-Soo Kim,Soohyun Kim 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

In the paper, the reinterpretation of a disturbance observer formulated in the transfer function domain is considered. Recalling that the disturbance observer produces an addtional disturbance suppresion performance to the existing closed-loop system, the idea of this paper is that the disturbance observer can be an add-on controller only to suppress the disturbances. By inducing the equivalent block diagram from generalized disturbance observer based control system [9], we obtain the equivalent feedback controller and the equivalent open-loop transfer function. Then, the role of a disturbance observer as an add-on controller is newly analyzed. Also, the reason of robust stability margin reduction phenomenon is explaned with the equivalent open-loop transfer function. The reinterpretation of a disturbance observer as an add-on controller is shown by a simple minimum-phase plant.

비정합 삼각함수 외란이 존재하는 시스템의 외란 보상 이득을 이용한 제어기 설계

한민수(Minsoo Han),김인혁(In Hyuk Kim),장수영(Su Young Jang),손영익(Young Ik Son) 제어로봇시스템학회 2018 제어·로봇·시스템학회 논문지 Vol.24 No.6

Disturbance observer-based controllers have been widely used in various control applications to compensate for plant uncertainties and external disturbances. This paper considers mismatched disturbances that do not satisfy the matching condition, which implies a disturbance enters the system in the same channels as the control input. The disturbance is supposed to be a biased sinusoidal signal with a known frequency. Since it is difficult to completely reject the effects of mismatched disturbances on the system, this paper proposes a controller to reduce the effect of mismatched disturbances on the output of the controlled system. The proposed controller consists of an observer-based state feedback controller and a compensation term using the estimated disturbance. By using the original system model, the proposed method estimates the system states, as well as a disturbance with unknown amplitude and phase but a known frequency. The estimated disturbance is used for the disturbance compensation input by multiplying the proposed disturbance compensation gain. To test the performance of the proposed method, comparative computer simulations have been performed for a fourth-order numerical example and a dc-motor system.

Input Disturbance Estimation Using a General Structured Observer

Lee, Choong-Hwan,Shin, Min-Saeng,Kim, Hwan-Seong,Kim, Sang-Bong The Korean Society of Mechanical Engineers 2001 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.15 No.12

This paper presents the characteristics of a general structured observer and presents an estimation algorithm for a system with external disturbances which are added to the input of the system. By using a disturbance model, the general structured observer can estimate the states of the system is spite of disturbances, where the system is affected from external disturbances. Also, the general structured observer can include the function of a PI observer or high gain observer by properly adjusting the observer's gain matrices. The existence condition for the observer is derived, which can be checked by the system's observability condition and the pole-zero cancellation of the system's polynomial matrix. Through a numerical example, it is verified that the proposed observer is effective estimating the system and the input disturbance.

Adaptive Transition Disturbance Observer for Winding Machine

Jinwook Kim,Oh-Kyu Choi,JinS. Lee 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

In this paper, we propose an adaptive transition disturbance observer for winding machine control. In winding machine control, keeping constant tensionon the winding material is one of the most important control objectives. So the reduction of the internal and external disturbance that can cause tension error is important. The disturbance observer is then proposed to solve these problems. But the conventional disturbance observer can not predict the tension error accurately, because the winder inertia changes according to the radius of the rewinding roll. By taking the change of the winder inertia in to account, we develop an adaptive transition disturbance observer that makes the system robust against the disturbance. The validity of the scheme is tested through simulation.

Compensator Design of Permanent Magnet Synchronous Linear Motor Control System Based on Load Disturbance Observer

Li Zheng,Zhang Zi-Hao,Wang Jin-Song,Wang Kang-Tao,Guo Xiao-Qiang,Fan Dao-Hu,Sun He-Xu 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

Aiming at the problem that the load disturbance generated by the permanent magnet synchronous linear motor (PMSLM) control system will affect its control performance and the load thrust of the PMSLM cannot be observed well, this design proposes two different load disturbance observers, namely the traditional Luenberger observer and novel internal model control (IMC) observer. The IMC observer observes the load disturbance in the form of proportional and integral, which can effectively improve the identification convergence speed and the compensation control effect. While observing the load disturbance, the two observers in this design can also use the generated thrust current compensation as the feedforward compensation of the system, to achieve disturbance suppression and effectively improve the control performance and robustness of the system. The PMSLM control system based on two observers is built in the simulation platform and the superiority of the designed control system is verified. Through the comparison and verification of the two observers and the no-observer system, it can be concluded that the control strategy can accurately track the load disturbance in the PMSLM, simplify the overall structure of the system, and effectively enhance the anti-disturbance capability and dynamic response capability of the PMSLM.

Study on sensorless force control based on disturbance observer with friction force compensation

Pattana Intani,Pattarawan Boonwong,Chowarit Mitsantisuk 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

This paper explained the disturbance observer, the system which is different from the force sensor control ,because the disturbance observer force control can observe the external torque without force sensors .If the system has the rigid mass or soft mass, concerning the environment, the disturbance observer can control and work well however when using disturbance observer in the system, it will also use the low-pass filter because the feedback following the amplitude rang was setting .when the system has friction force has to be improved by friction force compensation, this estimated method is called a reaction torque observer. Thus, the disturbance observer is a solution of the problem which happen by force sensor. For example, disturbance torque, can be applied as quickly as possible for the another systems.