Aircraft Preliminary Design Using Nonlinear Inverse Dynamics

Abstract What shape should an aircraft have to give certain desirable properties? Nonlinear Inverse Dynamics (NID) may be one of the necessary tools needed to find an answer to this question. In flight dynamics NID is usually applied to define flight trajectories calculations and flight control systems design. The underlying concept behind inverse dynamics applications is the definition of a desired manoeuvre, usually defined by a dynamical model or a pre-established trajectory. By forcing a aircraft whose dynamics are described by a set of nonlinear differential equations to behave like a prescribed model -non necessarily linearflight control systems are designed. This technique is referred to as nonlinear model matching. As follows NID is used to assist the preliminary design of aircraft. From a set of flight characteristics defined by customer specifications the parameters which define the shape and size, such as: wing span, weight, wing aerofoil selection, engine characteristics and wing polar are estimated.