Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
International Journal of Aeronautical and Space Sciences
Journal Basic Information
Journal DOI :
The Korean Society for Aeronautical & Space Sciences
Editor in Chief :
Volume & Issues
Volume 3, Issue 2 - Nov 2002
Volume 3, Issue 1 - May 2002
Selecting the target year
Robust and Optimal Attitude Control Law Design for Spacecraft with Inertia Uncertainties
Park, Yon-Mook ; Tahk, Min-Jea ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 1~12
DOI : 10.5139/IJASS.2002.3.2.001
This paper considers the robust and optimal three-axis attitude stabilization of rigid spacecraft with inertia uncertainties. The attitude motion of rigid spacecraft described in terms of either the Cayley-Rodrigues parameters or the Modified Rodrigues parameters is considered. A class of robust nonlinear control laws with relaxed feedback gain structures is proposed for attitude stabilization of rigid spacecraft with inertia uncertainties. Global asymptotic stability of the proposed control laws is shown by using the LaSalle Invariance Principle. The optimality properties of the proposed control laws are also investigated by using the Hamilton-Jacobi theory. A numerical example is given to illustrate the theoretical results presented in this paper.
Sliding Mode Attitude Control for Momentum-Biased Spacecraft
Bang, Hyo-Choong ; Loh, Young-Hwan ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 13~23
DOI : 10.5139/IJASS.2002.3.2.013
In this paper, we present a sliding mode control strategy for the re-orientation maneuver of rigid spacecraft containing rotating wheels. The wheels are considered as internal devices, and external inputs are employed for generation of control commands. The formulation is developed for a general case while particular example is applied to pitch bias momentum spacecraft with a single momentum wheel. The resultant control commands are used to take the gyroscopic effects into account which are caused by the rotating wheels. The controller designed demonstrates that the nutational motion of the pitch bias momentum spacecraft is effectively controlled. It is also assumed that the external control torque device is of on-off nature, and pulse width modulation technique is applied to construct proper control torque history.
Thermo-optic Effects of Bragg Grating Optical Temperature Sensor
Ahn, Kook-Chan ; Lee, Sang-Mae ; Lee, Gwang-Seok ; Park, Seung-Bum ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 24~30
DOI : 10.5139/IJASS.2002.3.2.024
This paper demonstrates a comparison of linear and nonlinear analyses for thermo-optic effects of optical temperature sensor based on the etched silica-based planar waveguide Bragg grating. Topics include theoretical analyses and experiment of the etched planar waveguide Bragg grating optical temperature sensor. Theoretical models with nonlinear than linear temperature effect for the grating response based on waveguide and plate deformation theories agree with experiments to within acceptable tolerance.
KOMPSAT-2 Fault and Recovery Management
Baek, Myung-Jin ; Lee, Na-Young ; Keum, Jung-Hoon ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 31~39
DOI : 10.5139/IJASS.2002.3.2.031
In this paper, KOMPSAT-2 on-board fault and ground recovery management design is addressesed in terms of hardware and software components which provide failure detection and spacecraft safing for anomalies which threaten spacecraft survival. It also includes ground real time up-commanding operation to recover the system safely. KOMPSAT-2 spacecraft fault and recovery management is designed such that the subsequent system configuration due to system initialization is initiated and controlled by processors. This paper will show that KOMPSAT-2 has a new design feature of CPU SEU mitigation for the possible upsets in the processor CPUs as a part of on-board fault management design. Recovery management of processor switching has two different ways: gang switching and individual switching. This paper will show that the difficulties of using multiple-processor system can be managed by proper design implementation and flight operation.
Radiation Analysis of Communications and Broadcasting Satellite
Park, Jae-Woo ; Chung, Tae-Jin ; Lee, Seong-Pal ; Seon, Jong-Ho ; Jeong, Yun-Whang ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 40~45
DOI : 10.5139/IJASS.2002.3.2.040
A radiation analysis is performed for the Ka and Ku-band transponder of the Communications and Broadcasting Satellite (CBS) that is planned for launch into the geo-synchronous orbit. A particular attention is given to calculation of Total Ionizing Dose (TID) for the mission life time of 15 + 3 years. A numerical modeling of the charged particles at the geo-synchronous orbit is undertaken. The charged particles from the modeling are then transported through the mechanical structure and component housings of the transponder. A set of locations are selected for the detailed calculation of TID. The results from the present calculation show that three-dimensional modeling of the component housings as well as the mechanical structure of the spacecraft is requisite in order to acquire a reliable calculation of TID.
A Validation Method for Solution of Nonlinear Differential Equations: Construction of Exact Solutions Neighboring Approximate Solutions
Lee, Sang-Chul ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 46~58
DOI : 10.5139/IJASS.2002.3.2.046
An inverse method is introduced to construct benchmark problems for the numerical solution of initial value problems. Benchmark problems constructed through this method have a known exact solution, even though analytical solutions are generally not obtainable. The solution is constructed such that it lies near a given approximate numerical solution, and therefore the special case solution can be generated in a versatile and physically meaningful fashion and can serve as a benchmark problem to validate approximate solution methods. A smooth interpolation of the approximate solution is forced to exactly satisfy the differential equation by analytically deriving a small forcing function to absorb all of the errors in the interpolated approximate solution. A multi-variable orthogonal function expansion method and computer symbol manipulation are successfully used for this process. Using this special case exact solution, it is possible to directly investigate the relationship between global errors of a candidate numerical solution process and the associated tuning parameters for a given code and a given problem. Under the assumption that the original differential equation is well-posed with respect to the small perturbations, we thereby obtain valuable information about the optimal choice of the tuning parameters and the achievable accuracy of the numerical solution. Illustrative examples show the utility of this method not only for the ordinary differential equations (ODEs) but for the partial differential equations (PDEs).
Determination of Cyclogram for Liquid-Propellant Rocket Engine
Ha, Seong-Up ; Kwon, Oh-Sung ; Lee, Jung-Ho ; Kim, Byoung-Hun ; Kang, Sun-Il ; Han, Sang-Yeop ; Cho, In-Hyun ; Lee, Dae-Sung ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 59~66
DOI : 10.5139/IJASS.2002.3.2.059
A vertical test stand based on launcher propulsion system was constructed and several tests for the determination of cyclogram were carried out. To make an accurate estimation, static and dynamic pressures were measured and analyzed. Especially, static pressure measurements using fast response sensors without extension tubes were used to determine operation sequence more evidently. The standard operation times of final valves were determined in cold flow tests with an engine head, and fire formation time in combustion chamber was checked in an ignition test with an ignitor only. On the basis of these tests, ignition sequence was established and combustion test cyclogram was finally determined. According to combustion test, test results were well matched with the determined cyclogram within 0.05 sec.
Engineering Applications of Jet Impingement Associated with Vertical Launching System Design
Hong, Seung-Kyu ; Lee, Kwang-Seop ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 67~75
DOI : 10.5139/IJASS.2002.3.2.067
In the course of missile system design, jet plume impingement is encountered in designing airframe as well as launchers, requiring careful investigation of its effect on the system. In the present paper, recent works on such topic are presented to demonstrate usefulness of CFD results in helping design the hardware. The jet impinging flow structure exhibits such complex nature as shock shell, plate shock and Mach disk depending on the flow parameters. The main parameters are the ratio of the jet pressure to the ambient pressure and the distance between the nozzle and the wall. In the current application, the nozzle contour and the pressure ratio are held fixed, but the jet impinging distance is varied to illuminate the characteristics of the jet plume with the distance. The same methodology is then applied to a complex vertical launcher system (VLS), capturing its flow structure and major design parameter. These applications involving jets are thus hoped to demonstrate the usefulness and value of CFD in designing a complex structure in the real engineering environment.
Study on Wake Roll-Up Behavior Behind Wings In Close Proximity to the Ground
Han, Cheol-Heui ; Cho, Jin-Soo ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 76~81
DOI : 10.5139/IJASS.2002.3.2.076
A numerical simulation of wake behavior behind three-dimensional wings in ground effect is done using an indirect boundary element method (Panel Method). An integral equation is obtained by applying Green`s 2nd Identity on all surfaces of the flow domain. The AIC is constructed by imposing the no penetration condition on solid surfaces, and the Kutta at the wing`s trailing edge. The ground effect is included using an image method. At each time step, a row of wake panels from wings` trailing edge are convected downstream following the force-free condition. The roll-up of wake vortices behind wings in close proximity is simulated.
Study on the Aerodynamic Characteristics of Wings Flying Over the Nonplanar Ground Surface
Han, Cheol-Heui ; Lee, Kye-Beom ; Cho, Jin-Soo ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 82~87
DOI : 10.5139/IJASS.2002.3.2.082
Aerodynamic analysis of NACA wings moving with a constant speed over guideways are performed using an indirect boundary element method (potential-based panel method). An integral equation is obtained by applying Green`s theorem on all surfaces of the fluid domain. The surfaces over the wing and the guideways are discretized as rectangular panel elements. Constant strength singularities are distributed over the panel elements. The viscous shear layer behind the wing is represented by constant strength dipoles. The unknown strengths of potentials are determined by inverting the aerodynamic influence coefficient matrices constructed by using the no penetration conditions on the surfaces and the Kutta condition at the trailing edge of the wing. The aerodynamic characteristics for the wings flying over nonplanar ground surfaces are investigated for several ground heights.
Scalar Adaptive Kalman Filtering for Stellar Inertia! Attitude Determination
Jung, Jae-Woo ; Cho, Yun-Cheol ; Bang, Hyo-Choong ; Tahk, Min-Jea ;
International Journal of Aeronautical and Space Sciences, volume 3, issue 2, 2002, Pages 88~94
DOI : 10.5139/IJASS.2002.3.2.088
This paper describes attitude determination algorithm for the low earth orbit(LEO) spacecraft using stellar inertial sensors. The cascaded gyro/star tracker extended Kalman filter is constructed to fuse two sensor data. And then the smoothing of the measurement are proposed for an unreasonable jump of star tracker. The smoothing algorithm for the rejection of star tracker error jumps is designed by scalar adaptive filter. The proposed algorithms operate to process the measurement of gyro/star tracker Kalman filter, therefore, it is comparatively simple to apply these methods to other integration systems. Simulations to gyro/star tracker integrated system show that the proposed method is effective.