Analysis of the applicability of PMD cameras for measuring altitude of flight near undisturbed water surface

Abstract

Landing on undisturbed surface of water is one of the most specific and complex elements of piloting seaplanes. The main reason for this is the complexity of visual assessment of altitude. Analysis showed that most of the existing methods and systems for contactless measurement of distance cannot be used for measuring flight altitude with required accuracy near water surface. Radio altimeters have the most suitable characteristics, however, for economic reasons, they are not installed on all seaplanes. Lack of accurate instrument information about the most important navigation parameter negatively affects the safety of flights. Above facts point to the importance of finding new methods of measuring flight altitude near undisturbed surface of water. For solving this problem, the paper focuses on analyzing the applicability of time-of-flight cameras, which are based on the Photonic Mixer Device (PMD) technology. The paper presents preliminary experimental results that confirm the possibility of using a static PMD camera for altitude measurement near undisturbed surface of water. Further, during landing the vertical velocity component and angular velocity of an aircraft do not have high values. The horizontal velocity component does not affect the view of range images in case of undisturbed water surface. Therefore an inference is made that PMD cameras can be used for measuring altitude of flight near undisturbed water surface.