Sun Young Noh

Kalman Filtering for TS Fuzzy State Estimation

This paper studies the T-S fuzzy model-based state estimator which the dynamic system can be approximated as linear system. It is suggested for a steady state estimator using standard Kalman filter theory. In that case, the steady state of nonlinear system can be represented by the T-S fuzzy model structure, which is further rearranged to give a set of a linear model. The steady state solutions can be found for a liner model method and dynamic system can be approximated as locally linear system. And then, linear modeled filter is corrected by the fuzzy gain which is a fuzzy system using the relation between the filter residual and its variation. It reduces the measurement residual with noise. Finally, the proposed state estimator is demonstrated on a truck-trailer

A fuzzy filter with missing measurement for observer-based T-S fuzzy models

This paper is concerned with the problem of a fuzzy filter of nonlinear system with missing measurements. The nonlinear system is represented by a Takagi-Sugeno(TS) fuzzy model. The system measurements may be unavailable at any sample time and the probability of the occurrence of missing data is assumed to be known. The purpose of this problem is to design a linear filter such that, the error state of the filtering process is mean square bounded. A basis-dependent Lyapunov function approach is developed to design the fuzzy filter, and it is developed the upper bound of a fuzzy filter gain of the estimation error subject to some LMI constraints. In this situation, the estimation error due to persistent bounded disturbances. Finally, an illustrative numerical example is provided to show the effectiveness of the proposed approach.

Optimal Fuzzy Filter for Nonlinear Systems with Variance Constraints

본 논문에서는 추정 분산 제약을 갖는 비선형 이산시간에 대한 최적의 퍼지 필터에 대한 내용을 다루고자 한다. 필터를 설계할 때, 추정오차의 분산값은 필터의 성능이 결정하는 변수중 하나다. 이런 분산값에 더욱 강인한 필터를 설계하고자, 분산 제약 조건을 주어 필터를 설계하고자 한다. 먼저, 비선형 모델을 Tagaki-Sugeno 퍼지 모델을 이용하여 선형 모델로 변형한 후, 이 모델을 기반으로 선형 필터를 디자인한다. 이때 필터설계 과정 중 필터의 각 파라미터값을 구하기 위해 상태 추정오차 값은 평균제곱에 제한되며, 상태오차의 정상상태 분산값은 각각의 미리 정한 상한 제한 값 보다 작은 조건에서 필터를 설계하여 선형행렬부등식과 대수 이차 행렬부등식을 이용하여 파라미터값을 구한다. 이렇게 설계된 퍼지 필터는 트럭트레일러 시뮬레이션을 통해 설계 과정과 성능을 보여준다.

Mixed-time T-S fuzzy optimal estimator for target tracking

This paper is concerned with the mixed-time fuzzy optimal estimator for the target tracking. The proposed method takes account of behaviour for target motion in continuous time and system measurement in discrete time. The overall dynamic of system in continuous-time is discretised by using Takagi-Sugeno(T-S) fuzzy models. Based on the fuzzy model the fuzzy estimation is studied. Then the error state of the filtering process is means square bounded. A basis dependent Lyapunov function approach is developed to design the fuzzy filter and a filter gain is minimized by using some linear matrix inequalities(LMIs) constraints. A numerical example is provided to demonstrate various aspects of theoretical results.

IMM method using tracking filter with fuzzy gain

In this paper, we propose an interacting multiple model (IMM) method using intelligent tracking filter with fuzzy gain to reduce tracking error for maneuvering target. In the proposed filter, the unknown acceleration input for each sub-model is determined by mismatches between the modelled target dynamics and the actual target dynamics. After an acceleration input is detected, the state estimate for each sub-model is modified. To modify the accurate estimation, we propose the fuzzy gain based on the relation between the filter residual and its variation. To optimize each fuzzy system, we utilize the genetic algorithm (GA). Finally, the tracking performance of the proposed method is compared with those of the input estimation(IE) method and AIMM method through computer simulations.

IMM Method Using Kalman Filter with Fuzzy Gain

In this paper, we propose an interacting multiple model (IMM) method using intelligent tracking filter with fuzzy gain to reduce tracking errors for maneuvering targets. In the proposed filter, the unknown acceleration input for each sub-model is determined by mismatches between the modelled target dynamics and the actual target dynamics. After a acceleration input is detected, the state estimates for each sub-filter are modified. To modify the accurate estimation, we propose the fuzzy gain based on the relation between the filter residual and its variation. To optimize each fuzzy system, we utilize the genetic algorithm (GA). The tracking performance of the proposed method is compared with those of the adaptive interacting multiple model(AIMM) method and input estimation (IE) method through computer simulations.

Design of Target Tracking System Using a New Intelligent Algorithm

When the maneuver occurs, the performance of the standard Kalman filter has been degraded because mismatches between the modeled target dynamics and the actual target dynamics. To solve this problem, the unknown acceleration is determined by using the fuzzy logic based on genetic algorithm(GA) method. This algorithm is the method to estimate the increment of acceleration by a fuzzy system using th relation between maneuver fitler residual and non-maneuvering one. To optimize this system, a GA is utilized. And then, the modified filter is corrected by the new update equation method which is a fuzzy system using the relation between the filter residual and its variation. To shows the feasibility of the suggested method with only one filter, the computer simulations system are provided, this method is compared with multiple model method.