Abstract:
A reaction wheel momentum distribution method is provided, which improves the attitude control mobility of satellite by calculating the zero torque of wheel through the simple calculation. The current speed and momentum of wheel are measured in real time. The measured current speed and the momentum are compared with the top speed and momentum set in advance. According to the current speed, momentum and top speed, and the difference of the momentum, the zero torque is calculated. The wheel torque required for the attitude control and stability of satellite is added to the zero torque. By using the input torque of the wheel, the wheel is made in the optimum bias momentum state.
Abstract:
본 발명 태양센서의 태양셀 정렬상태 오차 측정 및 보정 방법은, 위성의 태양센서를 몇가지 설치상태로부터 국부출력이 일치되는 때의 비틀림각을 측정하여 이 비틀림각으로부터 태양센서의 설치상태에 대한 오차를 계산하고 이를 보정하는, 태양셀 정렬상태 오차 측정 및 보정 방법에 관한 것이다. 본 발명은, ① 태양센서 설치수단 상부에 태양센서를 올려놓고 상기 태양센서와 태양광 모사수단이 일치되도록 초기정렬하는 제1단계와, ② 상기 제1단계의 초기정렬상태에서 상기 태양광 모사수단으로부터의 모사광에 따라, 제1상태로 위치시킨 상기 태양센서의 국부출력이 일치되는 지점에서 일정 기준선에 대한 상기 태양센서의 제1비틀림각(θ 1 )을 측정하는 제2단계와, ③ 상기 태양광 모사수단으로부터의 모사광에 따라, 제2상태로 위치시킨 상기 태양센서의 국부출력이 일치되는 지점에서 상기 기준선에 대한 상기 태양센서의 제2비틀림각(θ 2 )을 측정하는 제3단계와, ④ 상기 측정한 제1비틀림각(θ 1 ) 및 제2비틀림각(θ 2 )으로부터 초기정렬된 상기 태양센서(100)의 설치상태에 대한 오차를 도출하는 제4단계에 의해 정렬상태의 오차를 측정할 수 있으며, ⑤ 상기 제4단계에서 도출한 오차의 반대방향으로 보정하는 제5단계를 수행함으로써 측정된 오차를 보정할 수 있다. 따라서 본 발명은 보정수행 후 태양센서의 특성을 정확히 파악하고 측정 결 과의 부정확성을 줄이며 인공위성에 장착 시 지향 오차를 줄일 수 있는 효과를 제공한다. 태양 센서, 태양광 모사기, 광축, 정렬 오차, 평행 오차
Abstract:
PURPOSE: Provided is a position control experiment equipment for an artificial satellite which adjusts the height of copy structure for the artificial satellite to move weight center of the structure up and down so that it helps to coincide weight center of copy structure with rotation center of air bearing in an easy way. CONSTITUTION: The position control experiment equipment for the artificial satellite is characterized by fixing an up/down bolt with a screw formed outside at the intermediate lower part of the copy structure for the artificial satellite, interpolating the up/down bolt between a guide road in the upper part of the air bearing and a screw housing and inserting a nut into the exterior side of the up/down bolt to ride on a key and move up and down as the nut is rotated.
Abstract:
PURPOSE: A vibration and shock isolation device is provided to cut off vibration according to frequency through passive, semi-active, and active control of elastic members. CONSTITUTION: A vibration and shock isolation device(100) comprises one or more elastic members(130) which are interposed between a vibrating facility(200) and a structure(300). The elastic members include active elastomer(131) whose elastic coefficient and damping coefficient change according to voltage and passive elastomer(133) having fixed elastic coefficient and damping coefficient.
Abstract:
본 발명은 인공위성의 위성체 자세기동 시 사용하는 구동기 중 반작용휠과 추력기를 동시에 사용함으로써 기동성능 및 가제어성을 향상시키는 방법에 관한 것이다. 위성체 자세제어 시스템은, 위성체에 탑재된 추력기의 구동을 제어하는 추력기 기반 자세제어기(Thruster-Based Attitude Controller), 상기 위성체의 반작용휠의 구동을 제어하는 반작용휠 기반 자세제어기(Reaction Wheel-Based Attitude Controller) 및 상기 위성체의 자세를 변화시키는 위성체 동역학 모델(Spacecraft Dynamics)을 포함하여 구성된다. 여기서, 상기 위성체에는 상기 복수개의 반작용휠이 구비되고, 상기 반작용휠 중 일부의 고장으로 인한 결손 시 상기 추력기 기반 자세제어기와 상기 반작용휠 기반 자세제어기를 동시에 적용함으로써 위성체의 자세기동을 보정하게 된다. 인공위성 자세제어, 반작용휠(Reaction Wheel), 추력기(Thruster), 반작용휠 고장
Abstract:
PURPOSE: A posture angle sensor three dimensional misalignment correcting method using a monoscopic image is provided to implement the three dimensional misalignment calculation by using a single image information photographed by a camera. CONSTITUTION: A ground control point reference vector is calculated(S100). A ground control point observation vector is calculated by using the image information(S200). A posture error matrix is calculated by using the ground control point reference vector and the ground control point observation vector(S300). A posture angle sensor misalignment correction is implemented by using the posture error matrix calculation value(S400).
Abstract:
An integrated verification system for controlling a satellite attitude is provided to improve the efficiency of control logic verification by displaying a geometric appearance of a satellite in a three-dimensional space. An integrated verification system comprises a satellite dynamic simulator(10), a remote interface device(20), an embedded computer simulator(30), a satellite attitude control three-dimensional graphic visual device(40), a star simulator(50) and a host PC(60). The satellite dynamic simulator(10) includes a hardware having a commercial board and a custom board, and a software. The remote interface device(20) collects information on satellite attitude from an attitude control sensor, and sends the information to an attitude control logic.
Abstract:
The present invention relates to a resonant gyro and, more specifically, to the electrode shape of an electrode block for exciting, sensing, and controlling a resonant gyro. The hemispherical resonant gyro according to the present invention comprises a resonator having a hollow hemispherical shape to be excited; a support having a bar shape extended downward from the center of the hollow hemispherical shape of the resonator; an electrode block having a shape corresponding to the inner surface of the resonator and inserted in the resonator; a support groove formed downward from the center of the electrode block; and a base integrated with the electrode block and supporting the electrode block. The electrode block comprises an excitation electrode installed in the insertion surface of the electrode block to generate the vibration of the resonator, and a measurement electrode installed in the insertion surface of the electrode to measure amplitude when the resonator vibrates. The excitation electrode and the measurement electrode are radially arranged from the center of the insertion surface of the electrode block. The excitation electrode and the measurement electrode are arranged on the electrode block at each different height. The hemispherical resonant gyro enables effective excitation and precise measurement. Also, the hemispherical resonant gyro can prevent damage to the resonator due to excitation force by minimizing the magnitude of the stress applied to the support point of the resonator in the excitation.