• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.7
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• pp.1694-1704
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• 2015

In this paper, a robust trajectory tracking control method of a wheeled mobile robot is newly proposed combining the PDC and the ISMC. The PDC is a relatively simple and easy control method for nonlinear system compared to the other non-linear control methods. And the ISMC can have robust and stable control characteristics against model uncertainties and disturbances from the initial time by placing the states on the sliding plane with desired nominal dynamics. Therefore, the proposed PDC+ISMC trajectory tracking control method shows robust trajectory tracking performance in spite of external disturbance. The tracking performance of the proposed method is verified through simulations. Even though the disturbance increases, the proposed method keeps the performance of the PDC method when there is no disturbance. However, the PDC trajectory tracking control method has increasing tracking error unlike the proposed method when the disturbance increases.

• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.6
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• pp.598-604
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• 1999

A new fuzzy control algorithm for the control of active magnetic bearing (AMB) systems is proposed in th~sp aper. It combines PDC algorithm based on the LMI design of Joh et al. [4,5] and Mamdani-type control rules using fuzzy singletons to handle the nonlinear characteristics of AMB systems efficiently. They are named fine mode control and coarse mode control, respectively. The coarse mode control yields fast response for large deviation of the rotor and the fine mode control gives desired transient response for small deviation of the rotor. The proposed algorithm is applied to an AMB system to verify the performance of the proposed method. The comparison of the proposed method with a linear controller using a linearized model about the equilibrium point and the PDC algorithm show the superiority of the proposed algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.2
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• pp.265-276
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• 2017

In this paper, a robust and more accurate trajectory tracking control method for a mobile robot is proposed using WIPDC(Weighted Integral Parallel Distributed Compensation) and T-S Fuzzy disturbance observer. WIPDC reduces the steady state error by adding weighted integral term to PDC. And, T-S Fuzzy disturbance observer makes it possible to estimate and cancel disturbances for a T-S fuzzy model system. As a result, the trajectory tracking controller based on T-S Fuzzy disturbance observer shows robust tracking performance. When the initial postures of a mobile robot and the reference trajectory are different, the initial control inputs to the mobile robot become too large to apply them practically. In this study, also, the problem is solved by designing an initial approach path using a path planning method which employs $B\acute{e}zier$ curve with acceleration limits. Performances of the proposed method are proved from the simulation results.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.7
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• pp.496-501
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• 2016

This paper presents a design method of non-parallel distributed compensation (non-PDC) static output feedback controller for continuous- and discrete-time T-S fuzzy systems. The existence condition of static output feedback control law is represented in terms of linear matrix inequalities (LMIs). The proposed sufficient stabilizing condition does not need any transformation matrices and equality constraints and is less conservative than the previous result of [21].

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.951-954
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• 2001

본 논문에서는 SDR (Software Defined Radio)시스템을 위한 디지털 IF (Intermediate Frequency)수신기를 구현하였다[1][2]. 구현된 수신기의 하드웨어 구조는 AD변환부, PDC(Programmable Down Converter)부, DSP (Digital Signal Processing)부분으로 이루어졌다. AD변환부는 Analog Devices사의 AD6644를 이용하여 아날로그 신호를14bit의 디지털 신호로 변환된다. PDC부분은 Intersil사의 HSP 50214B를 이용하여 14bit 샘플 된 IF(Intermediate Frequency)입력을 혼합기와 NCO(Numerically Controlled Oscillator)에 의해 기저대역으로 다운 시키는 역할을 한다. PDC는 CIC (Cascaded Integrator Comb)필터, Halfband 필터 그리고 프로그램할 수 있는 FIR필터로 구성되어 있다. 그리고 PDC부분을 제어하고 PDC부분에서 처리할 수 없는 캐리어, 심볼 트래킹을 위해 Texas Instrument사의 16비트의 고정소수점 DSP인 TMS320C5416과 Altera사의 FPGA를 사용하였다. 그러므로 중간주파수 대역과 기저대역 간의 신호변환을 디지털 신호처리를 수행함으로써 일반적인 아날로그 처리방식보다 고도의 유연성과 고성능 동작이 가능하고 시간과 환경 변화에 우수한 동작 특성을 제공한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.12
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• pp.1043-1053
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• 2016

In this paper, the application of Parallel Distributed Compensation (PDC) controller for fixed pitch rotary wing system was studied. For nonlinear modeling, T-S fuzzy model was utilized to advance system control including the tilt type UAV. PDC controller was designed through the Linear Matrix Inequality (LMI). Experiments for determining the applicability and feasibility of PDC were performed using the 1 axis attitude control equipment and simulation. To verify the performance and characteristics of the controller, Mathworks Co. Simulink was used. After then, the PDC controller performance was verified and the results with developed controller using a 1 axis attitude control equipment were compared. Verification of the feasibility of PDC controller for the fixed pitch rotary wing system and identification of the overall performance and improvement analysis was conducted based on the experimental results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.973-983
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• 2015

To improve the control performance of the IPMSM, a novel nonlinear disturbance observer is proposed by using the T-S fuzzy model. A T-S fuzzy model is the combination of local linear models considered at each operating point. Usually the inverse model is easy to obtain in linear systems but not in nonlinear systems. To design a nonlinear disturbance observer, a nonlinear inverse model is obtained based on nonlinear inverse model which is the fuzzy combination of the local linear inverse models. The proposed DOB is used with a PDC controller which is one of the T-S fuzzy controller, and its performance improvement is shown from the simulation results.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.8
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• pp.771-775
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• 2001

In this paper, in order to control uncertain missile autopilot, an adaptive fuzzy control(AFC) scheme via parallel distributed compensation(PDC) is developed for the multi-input/multi -output plants represented by the Takagi-Sugeno(T-S) fuzzy model. Moreover adaptive law is designed so that the plant output tracks the stable reference model(SRM). From the simulations results, we can conclude that the suggested scheme can effectively solve the control problems of uncertain missile systems based on T-S fuzzy model.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.429-432
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• 1998

This paper is to design stable fuzzy controller so as to control chaotic nonlinear systems effectively via fuzzy control system and Parallel Distributed Compensation (PDC) design. To design fuzzy control system, nonlinear systems are represented by Takagi-sugeno(TS) fuzzy models. The PDC is employed to design fuzzy controllers from the TS fuzzy models. The stability analysis and control design problems is to find a common Lyapunov function for a set of linear matrix inequalitys(LMIs). The designed fuzzy controller is applied to Rossler system. The simulation results show the effectiveness of our controller.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2001.12a
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• pp.129-132
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• 2001

In this paper, in order to control uncertain missile autopilot, an adaptive fuzzy control(AEC) scheme via parallel distributed compensation(PDC) is developed for the multi-input/multi-output plants represented by the Takagi-Sugeno(T-S) fuzzy model. Moreover adaptive law is designed so that the plant output tracks the stable reference model(SRM), From the simulations results, we can conclude that the suggested scheme can effectively solve the control problems of uncertain missile systems based on T-S fuzzy model.