• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.104-109
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• 2002

A new robust Kalman filter is designed for the linear discrete-time system with norm-bounded parametric uncertainties. Sum quadratic constraint, which describes the uncertainties of the system, is converted into an indefinite quadratic form to be minimized in indefinite inner product space. This minimization problem is solved by the new robust Kalman filter. Since the new filter is obtained by simply modifying the conventional Kalman filter, robust filtering scheme can be more readily designed using the proposed method in comparison with the existing robust Kalman filters. A numerical example demonstrates the robustness and the improvement of the proposed filter compared with the existing filters.

• 항공우주시스템공학회지
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• 제10권1호
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• pp.21-28
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• 2016

Orbit determination problems have been interest of many researchers for long time. Due to the high nonlinearity of the equation of motion and the measurement model, it is necessary to linearize the both equations. To avoid linearization, the filter based on Fokker-Planck equation is designed. with the extended Kalman filter update mechanism, in which the associated Fokker-Planck equation was solved efficiently and accurately via discrete quadrature and the measurement update was done through the extended Kalman filter update mechanism. This filter based on the DQMOM and the EKF update is applied to the orbit determination problem with appropriate modification to mitigate the filter smugness. Unlike the extended Kalman filter, the hybrid filter based on the DQMOM and the EKF update does not require the burdensome evaluation of the Jacobian matrix and Gaussian assumption for the system, and can still provide more accurate estimations of the state than those of the extended Kalman filter especially when measurements are sparse. Simulation results indicate that the advantages of the hybrid filter based on the DQMOM and the EKF update make it a promising alternative to the extended Kalman filter for orbit estimation problems.

• 전력전자학회논문지
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• 제25권4호
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• pp.303-310
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• 2020

Estimating the accurate internal state of lithium ion batteries to increase their safety and efficiency is crucial. Various algorithms are used to estimate the internal state of a lithium ion battery, such as the extended Kalman filter and sliding mode observer. A state-space model is essential in using algorithms to estimate the internal state of a battery. Two principal methods are used to express the state-space model, namely, continuous time and discrete time. In this work, the extended Kalman filter is employed to estimate the internal state of a battery. Moreover, this work presents and analyzes the estimation performance of algorithms consisting of a continuous time state-space model and a discrete time state-space model through static and dynamic profiles.

• 제어로봇시스템학회논문지
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• 제7권4호
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• pp.362-368
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• 2001

We study on the velocity matching algorithm for transfer alignment of inertial navigation system(INS) using a robust H$_2$ filter. We suggest an uncertainty model and a discrete robust H$_2$filter for INS and apply the suggested robust H$_2$ filter to the uncertainty model. The discrete robust H$_2$filter is shown by simulation to have better performance time and accuracy than Kalman filter.

• International Journal of Precision Engineering and Manufacturing
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• 제8권1호
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• pp.52-58
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• 2007

We propose a new contact detection algorithm for fine pitch wire bonding. Fast and stable contact detection of the z-axis in wire bonding is extremely important to maintain the quality of fine pitch gold wire bonding processes, which use a small pad less than $70{\mu}m$ in diameter. A small perturbation in the contact detection time causes a large difference in the size of the formed squashed ball. The new detection method is based on a statistical approach and designed for a discrete Kalman filter. It is faster and has smaller detection time variations than conventional detection methods. Experimental results are presented to demonstrate the advantages of the proposed algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1411-1413
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• 2000

Distubance of air-gap sensors by rail irregularities are the serious problem deteriorating the performance in the electromagnetic suspension (EMS) systems. Thus, this paper proposes the output feedback controller with discrete kalman filter for the EMS systems. The discrete kalman filter estimate true state value and output feedback controller guarantee stability. The benefit of this scheme are shown by simulation. Therefore air-gap disturbance are rejected successfully.

• 전기학회논문지
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• 제66권2호
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• pp.468-473
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• 2017

This paper presents an in-process measurement system for shaft radius measurement during grinding process. This system does not require to stop the grinding process, which can enhance productivity and quality. In order to measure the radius, the system employs an eddy current sensor that can measure without any contact with the shaft. This type of sensor is very appropriate because it is insensitive to interference such as cutting fluid, coolant, contact pressure, and wear. For data analysis, the measurement system is modeled as a linearized discrete form where the states with noise are estimated by an extended Kalman filter. This system has been validated through simulations and experiments.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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• pp.432-435
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• 1995

In this paper a new approach to obtain the solution of the linear-quadratic Gaussian control problem for singularly perturbed discrete-time stochastic systems is proposed. The alogorithm proposed is based on exploring the previous results that the exact solution of the global discrete algebraic Riccati equations is found in terms of the reduced-order pure-slow and pure-fast nonsymmetric continuous-time algebraic Riccati equations and, in addition, the optimal global Kalman filter is decomposed into pure-slow and pure-fast local optimal filters both driven by the system measurements and the system optimal control input. It is shown that the optimal linear-quadratic Gaussian control problem for singularly perturbed linear discrete systems takes the complete decomposition and parallelism between pure-slow and pure-fast filters and controllers.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2022년도 춘계학술대회
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• pp.150-154
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• 2022

선박의 항적 및 선박 간 충돌 가능성을 평가하기 위해 선박자동식별시스템(AIS)이 중요하게 활용되고 있다. 하지만 전송 주기에 대한 한계로 인해 실시간 정보 제공이 어렵다. 이를 개선하기 위한 대부분의 연구는 이상적인 데이터를 기반으로 진행되어, 실제 상황에 대응하기 어려운 문제가 있다. 따라서 본 논문에서는 실상황에서의 실시간 정보 제공을 위해서, 항적의 유형에 따라 선회각을 반영한 이산 칼만 필터 기반 위치 추정 방법을 제안한다. 또, 실제 데이터를 사용한 실험을 통해서 제안 알고리즘에 대한 정확도 평가를 진행한다.

• Journal of applied mathematics & informatics
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• 제26권1_2호
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• pp.383-387
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• 2008

The problem of recursive filtering for discrete market model with unknown parameters is considered. In this paper, we develop an effective filtering algorithm for discrete market systems with unknown parameters and the error covariance equation determining the accuracy of the proposed algorithm is derived.