1. A method of implementing an optimal avoidance filter for interposing between movement commands issued by a human operator and a machine control system of a movable machine operated by the human operator, for the avoidance of collisions with objects, the method comprising: (a) inputting a detailed representation of the objects in a vicinity of the movable machine; (b) formulating a hierarchical set of bounding boxes around the objects, the hierarchical set including refinement details depending on a current positional state of the movable machine, with the objects closer to the movable machine having higher levels of refinement details; and (c) utilizing, by the processor, the hierarchical set as a set of constraints for an optimization program to determine any alterations to the issued movement commands so as to avoid collisions with the objects.