• Title/Summary/Keyword: Finite-time Sliding Mode Control

Search Result 29, Processing Time 0.031 seconds

An Adaptive Tracking Controller for Vibration Reduction of Flexible Manipulator

  • Sung Yoon-Gyeoung;Lee Kyu-Tae
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.7 no.3
    • /
    • pp.51-55
    • /
    • 2006
  • An adaptive tracking controller is presented for the vibration reduction of flexible manipulator employed in hazardous area by combining input shaping technique with sliding-mode control. The combined approach appears to be robust in the presence of severe disturbance and unknown parameter which will be estimated by least-square method in real time. In a maneuver strategy, it is found that a hybrid trajectory with a combination of low frequency mode and rigid-body mode results in better performance and is more efficient than the traditional rigid body trajectory alone which many researchers have employed. The feasibility of the adaptive tracking control approach is demonstrated by applying it to the simplified model of robot system. For the applications of the proposed technique to realistic systems, several requirements are discussed such as control stability and large system order resulted from finite element modeling.

Variable Structure Model Reference Adaptive Control, for SIMO Systems

  • mohammadi, Ardeshir Karami
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.1987-1992
    • /
    • 2004
  • A Variable Structure Model Reference Adaptive Controller (VS-MRAC) using state Variables is proposed for single input multi output systems. . The structure of the switching functions is designed based on stability requirements, and global exponential stability is proved. Transient behavior is analyzed using sliding mode control and shows perfect model following at a finite time. The effect of input disturbances on stability and transients is investigated and shows preference to the conventional MRAC schemes with integral adaptation law. Sliding surfaces are independent of system parameters and therefore VS-MRAC is insensitive to system parameter variations. Simulation is presented to clear the theoretical results.

  • PDF

Adaptive nonsingular sliding mode based guidance law with terminal angular constraint

  • He, Shaoming;Lin, Defu
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.15 no.2
    • /
    • pp.146-152
    • /
    • 2014
  • In this paper, a new adaptive nonsingular terminal sliding mode control theory based impact angle guidance law for intercepting maneuvering targets was documented. In the design procedure, a new adaptive law for target acceleration bound estimation was presented, which allowed the proposed guidance law to be used without the requirement of the information on the target maneuvering profiles. With the aid of Lyapunov stability criteria, the finite-time convergent characteristics of the line-of-sight angle and its derivative were proven in theory. Numerical simulations were also performed under various conditions to demonstrate the effectiveness of the proposed guidance law.

Velocity Control of Permanent Magnet Synchronous Motors using Model Predictive and Sliding Mode Cascade Controller (슬라이딩 모드 및 모델 예측 직렬형 제어기를 이용한 영구자석형 동기전동기의 속도제어)

  • Lee, Ilro;Lee, Youngwoo;Shin, Donghoon;Chung, Chung Choo
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.21 no.9
    • /
    • pp.801-806
    • /
    • 2015
  • In this paper, we propose cascade-form velocity controller for a permanent magnet synchronous motor (PMSM). The proposed controller consists of a sliding-mode controller (SMC) for the inner current control loop and a model-predictive controller (MPC) for the outer velocity control loop. With SMC, we can ensure that the current tracking error always converges to zero in finite time. The SMC is designed to track the desired currents. Additionally, with MPC, we can obtain the optimal velocity control input which minimizes the cost function. Constraint conditions for input and input variation are included in the MPC design. The simulation results are included to validate the performance of the proposed controller.

ORBITAL MANEUVER USING TWO-STEP SLIDING MODE CONTROL (2단 슬라이딩 제어기법을 이용한 인공위성의 궤도조정)

  • 박종옥;이상욱;최규홍
    • Journal of Astronomy and Space Sciences
    • /
    • v.15 no.1
    • /
    • pp.235-244
    • /
    • 1998
  • The solutions of orbital maneuver problem using the sliding mode control in the presence of the erath gravitational perturbations is obtained. Especially, the optimization of consuming fuel for maneuver is performed. The impulsive solution to Lambert's problem using the combined equation method to minimize total ${\Delta}V is used for the desired orbit and the maneuver times. Two-step sliding mode control method is introduced for satisfying the boundary conditions of finite-thrust rendezvous problem at the end of maneuver time. Using the new approach to the orbit maneuver problem, two-step sliding mode control, orbit maneuvers are processed. The solutions to a rendezvous using the optimal control are obtained, and they are compared to the results by two-step sliding control.According to the new approach for orbit maneuver, the thrust-coast-thrust type controller is obtained to make satellite to track desired Lambert's orbit, and the total ${\Delta}V$ required for maneuver is resonable in comparison with the impulsive solution to Lambert's problem. The final state variables, also are close to the boundary conditions at the end of maneuver times.

  • PDF

Variable structure control with fuzzy reaching law method for nonlinear systems (비선형 시스템에 대한 퍼지 도달 법칙을 가지는 가변 구조 제어)

  • Sa-Gong, Seong-Dae;Lee, Yeon-Jeong;Choe, Bong-Yeol
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.2 no.4
    • /
    • pp.279-286
    • /
    • 1996
  • In this paper, variable structure control(VSC) based on reaching law method with fuzzy inference for nonlinear systems is proposed. The reaching law means the reaching condition which forces an initial state of system to reach switching surface in finite time, and specifies the dynamics of a desired switching function. Since the conventional reaching law has fixed coefficients, the chattering can be existed largely in sliding mode. In the design of a proposed fuzzy reaching law, we fuzzify RP(representative point)'s orthogonal distance to switching surface and RP's distance the origin of the 2-dimensional space whose coordinates are the error and the error rate. The coefficients of the reaching law are varied appropriately by the fuzzy inference. Hence the state of system in reaching mode reaches fastly switching surface by the large values of reaching coefficients and the chattering is reduced in sliding mode by the small values of those. And the effectiveness of the proposed fuzzy reaching law method is showen by the simulation results of the control of a two link robot manipulator.

  • PDF

Robust Adaptive Sliding Mode Controller for PMSM Servo Drives System (강인 적응성 슬라이딩을 이용한 PMSM 서보드라이브 시스템 제어기)

  • Park, Ki-Kwang;Han, Byung-Jo;Kim, Hong-Pil;Yang, Hai-Won
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1640_1641
    • /
    • 2009
  • Dynamic friction and force ripple are the most predominant factors that affect the positioning accuracy of permanent magnet synchronous motor(PMSM) servo drives system, and it is desirable to compensate them in finite time with a continuous control law. In this paper, based on LuGre dynamic friction model, a robust adaptive skidding mode controller is proposed to compensate the nonlinear effect of friction and force ripple. The controller scheme consists of a PD component and a robust adaptive sliding mode controller for estimating the unknown system parameter. Using Lyapunov stability theorem, asymptotic stability analysis and position tracking performance are guaranteed. Simulation results well verify the feasibility and the effectiveness of the proposed scheme for high0precision motion trajectory tracking.

  • PDF

Dynamic Characteristics and Control of HDD Slider Integrated with SMA Actuator (SMA작동기와 연계된 HDD슬라이더의 동특성 및 제어)

  • Lim, S.C.;Park, J.S.;Park, C.J.;Choi, S.B.;Park, Y.P.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2000.11a
    • /
    • pp.217-224
    • /
    • 2000
  • This paper proposes a new type of HDD suspension integrated with shape memory alloy(SMA) actuator in order to prevent the friction between the slider and the disk. A finite element analysis is undertaken to investigate modal characteristics of the proposed self loading/unloading slider. The dynamic model is formulated and its validity is proved by comparing the predicted displacement transmissibility with the measured one. A control model is then established by integrating experimentally-obtained SMA actuator dynamics. Subsequently, a sliding mode controller is designed to achieve non-contact start/stop(Non CSS) modes, and control results are presented in time domain.

  • PDF

A computational analysis of the scarf angle on a composites repair

  • Kim, Yun-Hae;Jo, Young-Dae;Murakami, Ri-Ichi
    • International Journal of Ocean System Engineering
    • /
    • v.1 no.1
    • /
    • pp.9-15
    • /
    • 2011
  • This study examined the relationship between the scarf angle and stress distribution, and estimated the strength recovery via a finite element analysis. The following conclusions were drawn from this study. Resin will fracture due to a tensile load with a high scarf angle, which is similar to the patch repair method. An applied stress can be loaded to a repaired laminate if the scarf angle is $5^{\circ}$. The Von-Mises stress increases with decreasing scarf angle, with the exception of a scarf angle of $30^{\circ}$, where the scarf angle can indicate the rates of shear and normal stresses. Strength recovery can be better if the scarf angle is decreased to a lower angle. However, scarf machining requires more time, a high skill level and considerable expense. Therefore, a scarf angle of $5^{\circ}$ is the most effective for a repair. These results may provide a guide for engineers wishing to formulate a standard for repair. The scarf angle needs to be carefully managed for a more efficient composite repair.