This paper reports the authors’ ongoing experience with a system for discovering novel fighter combat maneuvers, using a geneticsbased machine learning process, and combat simulation. In effect, the genetic learning system in this application is taking the place of a test pilot, in discovering complex maneuvers from experience. The goal of this work is distinct from that of many other studies, ...

This paper considers the subject of straight-line target tracking for unmanned surface vehicles (USVs). Target-tracking represents motion control scenarios where no information about the target behavior is known in advance, i.e., the path that the target traverses is not defined apriori. Specifically, this work presents the design of a motion control system which enables an underactuated USV to...

n overview of hydrocode analysis at the Applied Physics Laboratory is presented. Starting with an Independent Research and Development project that simulated a high-velocity impact test of a full missile, the Laboratory developed a damage-scoring method for hydrocode simulations of missile impacts that opened the possibilities for a number of other applications. Applications of hydrocode analys...

Near-field acoustical holography methods are used to predict sound radiation from an engine installed on a high-performance military fighter aircraft. Cylindrical holography techniques are an efficient approach to measure the large and complex sound fields produced by full-scale jets. It is shown that a ground-based, one-dimensional array of microphones can be used in conjunction with a cylindr...

Several approaches for modelling the longitudinal aerodynamic coefficients of a fighter aircraft at high angles of attack, including the unsteady effects are presented. A traditional approach where the model of the coefficient arises in the form of the steady and unsteady effects, the unsteady effect being modelled by means of transfer functions. The second approach uses an internal variable de...

This paper presents an interpolation method for adapting projection-based ReducedOrder Models (ROMs) to new sets of physical and/or modeling parameters. The new method is based on the Grassmann manifold and its tangent space at a point and is applicable to many structural, fluid, and multidisciplinary engineering problems. It is illustrated here with the computational mechanics-based reduced-or...

An adaptive method that robustly produces high aspect ratio tetrahedra to a general 3D metric specification without introducing hybrid semi-structured regions is presented. The elemental operators and higher-level logic is described with their respective domaindecomposed parallelizations. An anisotropic tetrahedral grid adaptation scheme is demonstrated for 1000–1 stretching for a simple cube g...

The objective of this paper is to present and to evaluate the performance of particular fusion rules based on fuzzy T-Conorm/T-Norm operators for two tracking applications: (1) Tracking object’s type changes, supporting the process of objects’ identification (e.g. fighter against cargo, friendly aircraft against hostile ones), which, consequently is essential for improving the quality of genera...

In this paper a theoretical framework of robust fault-tolerant control (FTC) for a class of nonlinear nonaffine-in-control systems is developed. In the framework, an observer-like auxiliary system is designed via adaptive and sliding mode techniques, which is only required to ensure that the output of the auxiliary system asymptotic tracking plant output. Based on the auxiliary system, a reconf...

Fighter agility metrics determined from measured or calculated data can be sensitive to the coordinate system used. Although simple and intuitive, agility metrics expressed in Cartesian coordinates are not always robust to variations in initial conditions and uncertainties in physical characteristics. This paper seeks to establish the relationship between form of agility equations and the measu...