The absolute stabilization and optimal control of hydrofoil watercrafts
Journal Title: INCAS BULLETIN - Year 2018, Vol 10, Issue 4
Abstract
Hydrofoil watercrafts have a technology through which immersed wings are mounted under the hull. In the longitudinal movement case, these transversal wings are developing a carrying capacity which lifts the ship, thus decreasing the wet surface. The hydrodynamic lag decreases too, reaching economic fuel consumption as well. The paper deals with the analytic and graphic-numeric study, specifying the stable movement regime in the vicinity of the critical (equilibrium) points v1, v2, v3. The asymptotical stability is highlighted by using the Liapunov criteria, too. The practical control (self-stabilization) is obtained by using an automate speed controller (scanner), depending on wings flaps and the ship attack angle compared to the horizontal. It may be observed that (1) is in the category of cuspidal-returns from the Catastrophes Theory and bifurcations. Transversal waves or wind disturbances causes a ship flutter effect. For hydrofoil dynamics, an optimal control is finally applied, using the minimal time criterion related to Lev Pontryagin’s extremum principle.
Authors and Affiliations
Mircea LUPU, Cristian-George CONSTANTINESCU, Gheorghe RADU
Structural resource of the aircraft IAR-99 SOIM
Aircraft structure fatigue monitoring has been developed over decades presently reaching the stage where it became mandatory for all combat aircraft to be equipped with an airborne fatigue monitoring system. These system...
Preliminary Numerical Studies for the Improvement of the Ventilation System of the Crew Quarters on Board of the International Space Station
The current concept of Crew Quarters (CQ) aboard the ISS has several issues as recorded by NASA and ESA, the most important ones pertaining to the noise levels and the accumulation of CO2. Currently, 13% and 6%, respecti...
A Qualitative Comparison between the Proportional Navigation and Differential Geometry Guidance Algorithms
This paper discusses and presents an overview of the proportional navigation (PN) guidance law as well as the differential geometry (DG) guidance algorithm that are used to develop the intercept course of a certain targe...
Lamb Waves Tunning On Aluminium Plates for Structure Health Monitoring
The method for defects detection inside the mechanical structures, namely aerospace structures, using the Lamb waves is widespread because of its benefits: it is nondestructive, may reveal the presence and size of defect...
Using genetic algorithms to optimize airfoils in incompressible regime
Aerodynamic optimization is a very actual problem in aircraft design and airfoils are basic two-dimensional shape forming cross sections of wings. Traditionally, the airfoil geometry if defined by a very large number of...