C-Space Evaluation for Mobile Robots at Large Workspaces

In this work we present a hierarchical method to evaluate the configuration space of a mobile robot working in large environments. It is based on convolution of discrete functions representing the workspace and the robot to obtain a function that represents the C-space. An important key in the work is that the representation of discrete functions is made by hierarchical data structures, so the information is highly compact, and high dimensions or/and resolutions workspaces can be considered. It is important to highlight that the hierarchical data structures no only have been used for the representation, but for the evaluation. So, intermediate arrays to represent the discrete information are not used in the proposed method. Also, as the method is hierarchical, calculations at high resolutions are performed only in those regions where it is necessary. This makes the method suitable when the robot moves in large environments where other methods will fail due to the memory needs.