• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1995년도 추계학술대회 논문집
• /
• pp.598-601
• /
• 1995

This paper proposes a federated Kalman filter approach which utilizes information from multiple sensors and variable estimation model. Compared with the decentralized Kalman filter, the algorithm proposed in this paper demonstrates much better tracking performance in both maneuvering and constant velocity movement of the target.

• 한국항공운항학회지
• /
• 제24권2호
• /
• pp.1-10
• /
• 2016

A GPS/SDINS/ST(Star Tracker) integrated sensor algorithm is more robust than the GPS/SDINS and the ST/SDINS systems on exploration of other planets. Most of the advanced studies shown that GPS/SDINS/ST integrated sensor with centralized Kalman filter was more accurate than those 2 integrated systems. The system, however, consist of a single filter, it is vulnerable to defects on failed data. To improve the problem, we work out a study using federated Kalman filter(No-Reset mode) and centralized Kalman filter with adaptive measurement fusion which known as robustness on fault. The simulation results show that the debasing influences are reduced and the computation is enable at least 100Hz. Further researches that the initial calibration in accordance with observability and applying the exploration trajectory are needed.

• 한국군사과학기술학회지
• /
• 제15권5호
• /
• pp.557-564
• /
• 2012

This paper presents UGV localization using multi-sensor fusion based on federated filter in outdoor environments. The conventional GPS/INS integrated system does not guarantee the robustness of localization because GPS is vulnerable to external disturbances. In many environments, however, vision system is very efficient because there are many features compared to the open space and these features can provide much information for UGV localization. Thus, this paper uses the scene matching and pose estimation based vision navigation, magnetic compass and odometer to cope with the GPS-denied environments. NR-mode federated filter is used for system safety. The experiment results with a predefined path demonstrate enhancement of the robustness and accuracy of localization in outdoor environments.

• 한국항공우주학회지
• /
• 제38권10호
• /
• pp.1012-1019
• /
• 2010

본 논문에서는 다중표적 비행시험을 위한 비행 자료처리 시스템이 설계되었다. 비행자료 처리를 위해 표적그룹 처리, 자료융합 처리 및 자료연동 처리가 수행 되었으며, 자료융합 필터로서 집중형 칼만필터와 연합형 칼만필터를 설계하였다. 특히 집중형 필터에 레이더의 SNR과 추정기법을 적용하여 비행체의 저고도 계측을 개선하였다. 개발된 시스템을 다중표적 비행시험에 적용한 결과, 저고도 및 초기구간에서 개선된 비행궤적을 확인할 수 있었다.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2019년도 전력전자학술대회
• /
• pp.251-253
• /
• 2019

본 논문은 1.8kW (4.5kV, 450mA)출력의 마그네트론을 구동하기 위한 2.5kW (5kV, 0.5A) 고전압 DC 전원장치 설계에 대해 기술한다. 무선 전력 전송을 위한 위상배열 시스템에 이용되는 마그네트론의 경우 인가되는 전압의 리플 최소화는 필수적이다. 본 논문에서는 소프트 스위칭을 기반으로한 400kHz 이상의 스위칭 주파수로 컨버터를 설계함으로써 출력리플을 저감하고 필터성분을 최소화 하여 전력밀도를 높일 수 있도록 한다. 변압기의 누설인덕턴스 만을 이용하여 공진 인덕터를 구현하고 변압기의 기생 커패시터 성분과 직렬로 스택킹 된 출력 정류 다이오드의 전압 밸런싱을 위한 커패시터를 병렬 공진 커패시터로 활용한 LCC 공진형 컨버터 고밀도 설계에 대하여 기술한다. 또한, 공진전류의 Trapezoidal 해석 및 설계를 통해 도전 손실을 줄일 수 있는 LCC공진형 컨버터 기반의 마그네트론 구동전원 설계에 대하여 상세 기술하고 PSpice를 이용한 Simulation 및 실험 결과를 통하여 개발된 전원의 우수성을 검증한다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.1348-1351
• /
• 1997

The federated Kaman filter(FKF) is being widely used in many multisensor navigatiion systems. It is know that the FKF has advantages of simplicity and fault-tolerance over other decentralized filter techniques. In this paper, optimal and suboptimal FKF configuratiions are mentioned and a covariance analysis technique for the suboptimal FKF is newly presented. The suboptimal FKF configuration, known as No-reset(NR) mode, has better fault tolerance capability than the optimal FKF coniguratioin. In the suggested technique, a suboptimal fusion process of FKF is considered a swell as suboptimal gains of local filters. An upper boun of error covariance for suboptimal FKF is derived. Also, it is mathematically shown that this bound is smaller thanexisting bound in the literatrue. A vehicle-navigaion system is designed using the FKF. In thissystem, a map constraing equation is introduced and used as a measurement equatioin of Kalman filter. Performance analysis is done by the suggested covariance analysis techniques.

• 제어로봇시스템학회논문지
• /
• 제5권6호
• /
• pp.764-776
• /
• 1999

In this paper, a tracking algorithm for a maneuvering single target in the presence of multiple data from multiple sensors is investigated. Allowing individual sensors to function by themselves, the estimates from individual sensors on the same target are fused for the purpose of improving the state estimate. The filtering method adopted in the local sensors is the variable dimensional filter with input estimatio technique, which consists of a constant velocity model and a constant acceleration model. A posteriori probability for the maneuvering hypothesis is newly derived. It is shown that the relation function of the a posteriori probability is a function of only the covariance of the fused estimates. Simulation results are provided.

• 한국군사과학기술학회지
• /
• 제22권2호
• /
• pp.197-206
• /
• 2019

Safe aircraft requires highly reliable navigation information. The traditionally used inertial navigation system (INS) often displays faulty location information due to its innate errors. To overcome this, the INS/GNSS or INS/TRN integrated navigation can be used. However, GNSS is vulnerable to jamming and spoofing, while TRN can be degraded in the flat and repetitive terrains. In this paper, to improve the performance and ensure the high reliability of the navigation system, the INS/GNSS/TRN integrated navigation based on federated filter is designed. Master filter of the integrated navigation uses the estimates and covariances of two local filters - INS/GNSS and INS/TRN integrated filters. The local filters are designed with the EKF that is feedforward type and composed of the 17st state variables. And the INS/GNSS integrated navigation includes the barometer error compensation method. Finally, the proposed INS/GNSS/TRN integrated navigation is verified by vehicle and captive flight tests.