Method of controlling an autonomous device

Method of controlling an autonomous device comprising:

• locating a first position of an autonomous device;
• when the autonomous device moves to a second position associated with a global occupancy grid and a local occupancy grid:
• updating the global occupancy grid with an occupied probability value associated with the first position;
• updating the global occupancy grid with a surface having a drivable surface classification, defining a drivable surface, associated with the local occupancy grid;
• updating the global occupancy grid with a classification confidence value associated with the drivable surface classification;
• updating the global occupancy grid with logodds of the occupied probability value using a first Bayesian function;
• and
• adjusting the logodds based on characteristics associated with the second position;
• and
• when the autonomous device remains in the first position and the global occupancy grid and the local occupancy grid are co-located:
• updating the global occupancy grid with the drivable surface associated with the local occupancy grid;
• updating the global occupancy grid with the classification confidence value associated with the drivable surface;
• updating the global occupancy grid with the logodds of the occupied probability value using a second Bayesian function;
• adjusting the logodds based on characteristics associated with the second position;
• and
• navigating the autonomous device based on the updated global occupancy grid.