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arXiv · 1910.06066

Mind the ground: A Power Spectral Density-based estimator for all-terrain rovers

Giulio Reina·Antonio Leanza·Annalisa Milella·Arcangelo Messina
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Abstract

There is a growing interest in new sensing technologies and processing algorithms to increase the level of driving automation towards self-driving vehicles. The challenge for autonomy is especially difficult for the negotiation of uncharted scenarios, including natural terrain. This paper proposes a method for terrain unevenness estimation that is based on the power spectral density (PSD) of the surface profile as measured by exteroceptive sensing, that is, by using a common onboard range sensor such as a stereoscopic camera. Using these components, the proposed estimator can evaluate terrain on-line during normal operations. PSD-based analysis provides insight not only on the magnitude of irregularities, but also on how these irregularities are distributed at various wavelengths. A feature vector can be defined to classify roughness that is proved a powerful statistical tool for the characterization of a given terrain fingerprint showing a limited sensitivity to vehicle tilt rotations. First, the theoretical foundations behind the PSD-based estimator are presented. Then, the system is validated in the field using an all-terrain rover that operates on various natural surfaces. It is shown its potential for automatic ground harshness estimation and, in general, for the development of driving assistance systems.

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Giulio Reina, Antonio Leanza, Annalisa Milella, Arcangelo Messina. 2019-10-14. Mind the ground: A Power Spectral Density-based estimator for all-terrain rovers. https://doi.org/10.1016/j.measurement.2019.107136

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