Planetary Rovers’ Wheel Sinkage Detection Based on Wheel-Soil Boundary

Abstract

The detection of wheel sinkage has great significance for rover mobility optimization control and prevention of wheel sinking. A new wheel sinkage detection method is proposed based on planetary rovers' wheel-soil boundary. The model of wheel sinkage calculation is built. The machine vision method is proposed to extract wheel-soil boundary. Wheel-soil interaction image is processed into binary image, and the wheel-soil boundary is extracted according to its morphological features. The wheel sinkage depth, entrance angle and departure angle are calculated through the model of wheel sinkage calculation. The method's applicability has been validated by experiments under various terrain conditions, which are flat terrain, raised terrain, hollow terrain, and rough terrain. Accuracy tests are done with the flat terrain, the results of the experiments indicate that the relative errors of the sinkage depth are around 10% and the relative errors of terrain interface angles are around 5%, when the actual sinkage depth is above 5mm.

A Real-Time Sinkage Detection Method for the Planetary Robotic Wheel-on-Limb System via a Monocular Camera

“…However, its main limitations include noise insensitivity and high image quality requirements. In 2015, Lv Fengtian [19] introduced a wheel-soil boundary extraction method based on machine vision and saturation. The method extracts the wheel contour by transforming the image space and image binary processing.…”