Showing papers in "Aerospace Science and Technology in 2011"

TL;DR: It is shown that the INS attitude alignment can be equivalently transformed into a “continuous” attitude determination problem using infinite vector observations.

TL;DR: In this article, structural analysis of a solid propellant rocket motor using the finite element method was performed to determine the effects of aging on the analysis results, and the results can be used to estimate the service life of the motor.

TL;DR: In this paper, a closed-form feedback controller was proposed to control the position and attitude of rigid body and suppression of flexural deformation in one optimal control framework for a tumbling target.

TL;DR: In this article, the damping characteristics of three-type resonators, a half-wave, a quarter-wave and a Helmholtz resonator are studied experimentally by adopting linear acoustic test.

TL;DR: In this article, a CAD/CAE-based multidisciplinary process for the mass estimation of transport aircraft wingbox structures is described, which is based on physics-based and emulates the structural design process that takes place during the preliminary design phase.

TL;DR: In this article, the robust non-fragile Kalman-type recursive filtering problem is studied for a class of uncertain systems with finite-step autocorrelated measurement noises and multiple packet dropouts.

TL;DR: In this article, a robust adaptive filtering method for SINS/SAR (Strap-down Inertial Navigation System/Synthetic Aperture Radar) integrated navigation system is presented.

TL;DR: In this article, the authors present a numerical analysis of the incompressible flow at Reynolds number 6.0 × 10 4 around the Selig-Donovan 7003 airfoil.

TL;DR: In this article, an electrical conductance method was used to measure the liquid film thickness formed in an open-end swirl injector which is commonly used in Russian liquid-oxygen (LOX)/kerosene engines such as RD-120, RD-170, and RD-180.

TL;DR: In this article, a nonsingular terminal sliding mode controller is presented to overcome the singularity problem in attitude tracking in rigid spacecraft, which will cause the instability of the closed-loop system of attitude tracking errors.

TL;DR: In this paper, it is proposed to use air jets to generate streamwise vortices (AJVG) for interaction control, and the results presented here concern experimental investigations and provide new guidelines for the design of AJVGs.

TL;DR: In this article, the authors presented optimal reconfiguration and formation-keeping for formation flying satellites using the state-dependent Riccati equation (SDRE) technique as a non-linear controller.

TL;DR: In this paper, a pressure wave propagation model for gas-liquid two-phase flow with phase change taken into consideration is first proposed by using ensemble-averaging techniques, and then condensation of gas oxygen in subcooled liquid oxygen and the corresponding mixing process in pump pipeline are numerically simulated with the application of thermal phase change model in Computational Fluid Dynamics code CFX.

TL;DR: In this article, a single Augmented Dynamics Extended Kalman Filter (ADEKF) is configured by combining the spacecraft nonlinear attitude dynamics and quaternion kinematics with orbital mechanics.

TL;DR: A composite adaptive fuzzy proportional-integral-derivative (PID) control with hysteresis-band switching is developed to achieve real-time and high stabilization precision for this nonlinear uncertainty servo system and is proved to be effective in bating carrier disturbances within the scope of definite noise and sensitivity to acceleration.

TL;DR: An improved self-alignment scheme for strapdown Inertial Navigation System (SINS) based on the extended Kalman filter (EKF) and augmented measurements is proposed.

TL;DR: In this paper, a Timoshenko beam (TB) resting on two-parametric (or Pasternak) elastic foundation (PEF) is developed for determination of strain energy release rate (SERR) of mode-I delamination in multidirectional double cantilever beam (DCB) specimens.

TL;DR: In this paper, the effect of velocity flow field measurements of the vortex system for a small scale model intake have been taken using a three component PIV system along with fan face total pressure distortion measurements under quiescent and headwind conditions.

TL;DR: In this paper, an unscented Kalman filter (UKF) is employed to determine the biases associated to each accelerometer and gyro in the inertial measurement unit (IMU), together with high sampling-rate trajectory reconstruction from low frequency sampled GPS data.

TL;DR: Aeroelastic two-dimensional wing section with both trailing edge (TE) and leading-edge (LE) was investigated in this article through numerical simulation in time domain, and the results show that the designed control laws are effective for flutter suppression, and that considering damping uncertainty has positive effect on flutter control.

TL;DR: In this paper, a third order shear deformation theory is used to study the behavior of laminated smart composite plate with magnetostrictive layers, while accounting for geometric nonlinearity in the von-Karman sense.

TL;DR: In this article, a Cubesat mission with a deployable solar sail of 5 meters by 5 meters in a sun-synchronous low earth orbit is analyzed to demonstrate solar sailing using active attitude stabilization of the sail panel.

TL;DR: In this article, a procedure to compute guidance commands for controlling the relative geometry of multiple UAVs in formation flight is proposed, where the concepts of branch, global leader, and local leader/follower are used to represent the whole formation geometry.

TL;DR: In this article, an analytical model is developed and the discrete finite element method is adopted to investigate the vibration and damping characteristics of the sandwich orthotropic cylindrical shell system with an electrorheological (ER) layer and a constraining layer.

TL;DR: In this article, a single plate of aluminum 7075-T6 bolted with different applied torques has been numerically investigated and the total estimated fatigue lives have been compared with available experimental fatigue test results.

TL;DR: In this article, a set of complete six degrees of freedom aircraft's equations of motion is taken in a variation formulation of this problem to determine the optimal escape or approach trajectories constrained with respect to physical controls as well as some crucial motion states.

TL;DR: Using flight test data, it is shown that local model networks are useful in the identification of models that have to cover a broad range of flight conditions.

TL;DR: In this paper, an overview of the reported susceptibility model for IR-guided missiles is presented, and a model is proposed to study the aircraft susceptibility when aircraft speed is less, equal and more than the speed of the attacking missile.

TL;DR: In this article, a pressure-based implicit procedure to solve Navier-Stokes equations on a nonorthogonal mesh with collocated finite volume formulation is used to evaluate the aerodynamic characteristics of two-dimensional smart flap under the ground effect.

TL;DR: In this paper, the effect of scalloping on the lift and drag force coefficients of membrane wings was investigated and a series of rigid, flat plate frames with moderate aspect ratio and repeating membrane cell structure were compared to a rigid plate and a rigid scalloped plate.