when the orbital altitude of a small satellite is near-earth, passive stabilization can be considered. the purpose of this paper is to combine the passive gravity gradient and aerodynamic stabilization methods together so that all the three axes stabilizations can be obtained. in this regard, the set of nonlinear equations of motion will be solved numerically with specified initial condition. t...

An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity finiteelement structural analysis and computational fluid dynamics aerodynamic analysis in a distributed, heterogeneous computing environment that includ...

some physical properties such as geometrical, gravimetrical, frictional and aerodynamic features of seeds of desi chickpea and its splits were studied at a moisture content of 8.2 and 9.0% w., respectively from north-western of iran. geometrical and gravimetrical properties including the average length, width, thickness, the geometric mean of diameter, sphericity, 1000-seed weight, unit weight,...

This paper is concerned with the control allocation strategies with the two-time scale dynamic inversion which generate nominal control input trajectories. In addition, an robust flight control design method is proposed by using a time-varying control technique which is a timevarying version of the pole placement of the linear time-invariant system for an agile missile with aerodynamic fin, thr...

A recent focus on revolutionary aerodynamic concepts has highlighted the technology needs of general aviation and personal aircraft. New and stringent restrictions on these types of aircraft have placed high demands on aerodynamic performance, noise, and environmental issues. Improved high lift performance of these aircraft can lead to slower takeoff and landing speeds that can be related to re...

Swifts are aerodynamically sophisticated birds with a small arm and large hand wing that provides them with exquisite control over their glide performance. However, their hand wings have a seemingly unsophisticated surface roughness that is poised to disturb flow. This roughness of about 2% chord length is formed by the valleys and ridges of overlapping primary feathers with thick protruding ra...