A Dynamic Visibility Inference Scheme Based on New Spatial Knowledge Representations from Observer’s Perspective

Abstract

In this article, we propose two new spatial knowledge representations called OG-string and Visibility-string for a dynamic environment seen from the observer’s perspective. The OG-string preserves the objects’ VBSs (Virtual Blocking Set) and can be used to determine visibility of objects. Because of having the same VBS, objects with the same begin-bound in ring-direction are grouped together. As a result the size of OG-string also can be reduced. The Visibility-string contains the objects’ visibility information, and thus can cooperate with OG-string to provide enough spatial information for dynamic visibility inference. We also represent a Dynamic Visibility Inference Scheme consisting of an Initialization, an Addition and a Deletion Algorithm based on the two new representations. The scheme assist with visibility inference for a dynamic environment where objects are added and deleted frequently just like in a warehouse so that a mobile robot’s path planning can be improved.