• 제목/요약/키워드: Yaw angle

검색결과 325건 처리시간 0.03초

Gyroless Yaw Angle Compassing of Earth-Pointing Spacecraft Using Magnetic Sensor

  • Lee, Seon-Ho;Ahn, Hyo-Sung;Rhee, Seung-Wu
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2004년도 ICCAS
    • /
    • pp.2055-2058
    • /
    • 2004
  • This paper formulates a yaw angle determination algorithm for earth-point satellite. The algorithm based on vector observation, is implemented with the limited vector measurements. The proposed algorithm doesn't require gyro measurement data but magnetic sensor measurement data. In order to confirm the usefulness of the proposed method, we investigate the simulated telemetry data of the KOMPSAT-2, a satellite that is scheduled to be launched into a 685km altitude sun synchronous circular orbit in 2005.

  • PDF

영역분할과 2차원 커브피팅 함수들을 이용하는 직선형 5공 압력프로브의 성능 평가 (The Performance Assessment of a Straight-Type Five-Hole Pressure Probe Using a Zone Partition and Two-Dimensional Curve-Fitting Functions)

  • 김장권;오석형
    • 동력기계공학회지
    • /
    • 제18권1호
    • /
    • pp.22-31
    • /
    • 2014
  • This paper introduced the new calibration algorithm of a straight-type five-hole pressure probe necessary for calculating three-dimensional flow velocity components. The new velocity data reduction method using both a commercial two-dimensional curve-fitting program and the zone partition method of a calibration map was firstly introduced in this study. This new calibration method can be applied up to the wide flow angle of ${\pm}80^{\circ}$ despite of using a five-hole pressure probe because this data reduction method showed a comparatively good performance in calculating yaw and pitch angles from the calibration map.

Van형 자동차의 후류구조에 대한 실험적 해석(와류 형성을 중심으로) (An experimental study on the wake structure behind a van type vehicle)

  • 성봉주;장병희
    • 오토저널
    • /
    • 제10권3호
    • /
    • pp.51-59
    • /
    • 1988
  • The wake structure behind a van type vehicle was studied experimentally with a 5-hole yawhead probe. Through an effective calibration method of the 5-hole yawhead probe, the flow properties such as velocity vector, total pressure and static pressure were obtained on two cross sections within the wake. These results combined with the surface flow visualization performed in the previous study, yielded some information about the wake structure. When the model was placed in a stream with zero yaw angle, two counter rotating vortices were observed behind the model which pull down the surface flow on each side of the model. With increasing the yaw angle, the surface flow on the windward side changed to divide the flow in two directions, one flows upward on the upper part and the other flows downward on the lower part of the windward side. Hence a new weak vortex was created on the upper windward side, which resulted 3 vortices within the wake. The size and the strength of the vortices increased with yaw angle.

  • PDF

Sonar-based yaw estimation of target object using shape prediction on viewing angle variation with neural network

  • Sung, Minsung;Yu, Son-Cheol
    • Ocean Systems Engineering
    • /
    • 제10권4호
    • /
    • pp.435-449
    • /
    • 2020
  • This paper proposes a method to estimate the underwater target object's yaw angle using a sonar image. A simulator modeling imaging mechanism of a sonar sensor and a generative adversarial network for style transfer generates realistic template images of the target object by predicting shapes according to the viewing angles. Then, the target object's yaw angle can be estimated by comparing the template images and a shape taken in real sonar images. We verified the proposed method by conducting water tank experiments. The proposed method was also applied to AUV in field experiments. The proposed method, which provides bearing information between underwater objects and the sonar sensor, can be applied to algorithms such as underwater localization or multi-view-based underwater object recognition.

휠 슬립에 강건한 확장칼만필터 기반 차량 상태 추정 (Vehicle State Estimation Robust to Wheel Slip Using Extended Kalman Filter)

  • 전명근;조아라;이경수
    • 자동차안전학회지
    • /
    • 제14권4호
    • /
    • pp.16-20
    • /
    • 2022
  • Accurate state estimation is important for autonomous driving. However, the estimation error increases in situations that a lot of longitudinal slip occurs. Therefore, this paper presents a vehicle state estimation method using an Extended Kalman Filter. The filter estimates the states of the host vehicle robust to wheel slip. It utilizes the measurements of the four-wheel rotational speeds, longitudinal acceleration, yaw-rate, and steering wheel angle. Nonlinear measurement model is represented by Ackermann Model. The main advantage of this approach is the accurate estimation of yaw rate due to the measurement of the steering wheel angle. The proposed algorithm is verified in scenarios of autonomous emergency braking (AEB), lane change (LC), lane keeping (LK) using an automated vehicle. The results show that the proposed algorithm guarantees accurate estimation in such scenarios.

KOMPSAT-2 위성의 요각 계산방법 연구

  • 김정아;강금실;장영준;용상순;강성덕;윤형식
    • 항공우주기술
    • /
    • 제3권2호
    • /
    • pp.160-169
    • /
    • 2004
  • KOMPSAT-2 위성의 MSC는 고해상도 위성영상을 얻기 위하여 TDI 기능을 적용하고, 위성 운영방법으로 자세각 요각에 대한 제어를 요구한다. 본 연구에서는 TDI 기능의 개념과 요구되는 조건을 만족하는 위성의 요각을 계산하기 위하여 촬영궤적평면의 기하관계를 설정하여 최종적으로 요각의 계산식을 구하였다. 이를 바탕으로 프로그램을 작성하고 시뮬레이션 하여 궤도와 촬영 자세각에 따른 요각의 계산결과를 탑재컴퓨터에서 설정되는 요각과 비교하였다.

  • PDF

비선형 타이어모델을 이용한 완전능동형 4WS 제어방법에 관한 연구 (A Study on the Full Active 4WS Control Method Using Nonlinear Tire Model)

  • 김형내;김석일;김동룡;김건상
    • 한국자동차공학회논문집
    • /
    • 제5권3호
    • /
    • pp.76-85
    • /
    • 1997
  • The understeer characteristics of four wheel steering system(4WS system) in a high speed region have a negative effect upon the yaw velocity, leading to a decrease in the handling ability of vehicle. As a result, even if the side slip angle of vehicle can be kept up a minimum, a driver must compensate a decrease in yaw velocity by increasing the steering wheel angle in order to track the desired vehicle path. In this study, to keep the side slip angle of vehicle at zero and achieve a suitable yaw velocity in vehicle motion, a full active 4WS system(FA 4WS system) with actively steerable front and rear wheels is presented based on a nonlinear vehicle model and a model following control of yaw velocity. And the analysis results show the fat that, besides the excellent stability of vehicle, the FA 4WS system is able to realize better handling performance of vehicle than the previous 4WS systems in the high speed region.

  • PDF

Roll-Pitch-Yaw Integrated H Controller Synthesis for High Angle-of-Attack Missiles

  • Choi, Byung-Hun;Kang, Seon-Hyeok;Kim, H. Jin;Won, Dae-Yeon;Kim, Youn-Hwan;Jun, Byung-Eul;Lee, Jin-Ik
    • International Journal of Aeronautical and Space Sciences
    • /
    • 제9권1호
    • /
    • pp.66-75
    • /
    • 2008
  • In this work, we explore the feasibility of roll-pitch-yaw integrated autopilots for high angle-of-attack missiles. An investigation of the aerodynamic characteristics of a surface-to-air missile is presented, which reveals the strong effects of cross coupling between the longitudinal and lateral dynamics. Robust control techniques based on $H_{\infty}$ synthesis are employed to design roll-pitch-yaw integrated autopilots. The performance of the proposed roll-pitch-yaw integrated controller is tested in high-fidelity nonlinear five-degree-of-freedom simulations accounting for kinematic cross-coupling effects between the lateral and longitudinal channels. Against nonlinearity and cross-coupling effects of the missile dynamics, the integrated controller demonstrates superior performance when compared with the controller designed in a decoupled manner.

충돌회피를 위한 가속도를 고려한 차선 변경 시스템 개발 (Development of Lane Change System considering Acceleration for Collision Avoidance)

  • 강현구;이동휘;허건수
    • 한국자동차공학회논문집
    • /
    • 제21권2호
    • /
    • pp.81-86
    • /
    • 2013
  • This paper presents the lane change system for collision avoidance. The proposed algorithm for the collision avoidance consists of path generation and path following. Using a calculated TTC (Time to Collision), partial braking is operated and collision avoidance path is generated considering relative distance, velocity and acceleration. Based on the collision avoidance path, desired yaw angle and yaw rate are calculated for the automated path following. The lateral controller is designed by a Lyapunov function approach using 3 D.O.F vehicle model and vehicle parameters. The required steering angle is determined from wheel velocity, longitudinal and lateral velocity in order to follow the desired yaw angle and yaw rate. This system is developed MATLAB/Simulink and its performance is evaluated using the commercial software CarSim.

UIO를 이용한 선회 시 등판각 추정 (Climbing Angle Estimation in Yawing Motion by UIO)

  • 변형규;김현규;김인근;허건수
    • 한국자동차공학회논문집
    • /
    • 제23권5호
    • /
    • pp.478-485
    • /
    • 2015
  • Availability of the climbing angle information is crucial for the intelligent vehicle system. However, the climbing angle information can't be measured with the sensor mounted on the vehicle. In this paper, climbing angle estimation system is proposed. First, longitudinal acceleration obtained from gyro-sensor is compared with the actual longitudinal acceleration of the vehicle. If the vehicle is in yawing motion, actual longitudinal acceleration can't be approximated from time derivative of wheel speed, because lateral velocity and yaw rate affect actual longitudinal acceleration. Wheel speed and yaw rate can be obtained from the sensors mounted on the vehicle, but lateral velocity can't be measured from the sensor. Therefore, lateral velocity is estimated using unknown input observer with nonlinear tire model. Simulation results show that the compensated results using lateral velocity and yaw rate show better performance than uncompensated results.