Statistical and probabilistic path planning for aircraft with performance uncertainties.

摘要

An algorithm and software package are developed for distressed aircraft path planning to handle performance uncertainties. Following a damage event, aircraft turn radii, time aloft and landing roll performance variables are limited and uncertain. Performance variables are modeled probabilistically with normal cumulative distribution functions. A set of paths are built from three straight and two circular turn segments. The set includes combinations of multiple runways and multiple values for segment geometries. Initial turn radius, final turn radius, time aloft and runway length are stored for each path and checked against the performance distribution functions. A probability hierarchy defines the sequential combination of the individual parameters into a total probability of safety for the path. In parallel to probabilistic analyses, the paths are collectively analyzed and ranked according to a statistical model. The statistical model includes pilot interface terms and is designed to bias results away from the potential effects of uncertainties. The combined software package is designed for computational efficiency. Results are delivered at a rate of 7,413 paths per second on an IntelRTM Core(TM) 2 Quad Q6600 2.39 GHz processor running Windows XP Professional x64 Service Pack 2 and MATLAB R2007a. Results show the software is useful for specific damage cases such as uncertain damage, engine damage and asymmetric damage.