Automated perception of safe docking locations with alignment information for assistive wheelchairs

There are basic manuvering tasks with a powered wheelchair, like docking under a table and passage through a doorway or narrow hallway, which can be difficult for users with severe motor impairments - not only because of limitations in their own motor control, but also because of limitations in the control interfaces available to them. Robot automation can help transfer some of this control burden from the user to the machine. This work presents an algorithm for the automated detection of safe docking locations at rectangular and circular docking structures (tables, desks) with proper alignment information using 3D point cloud data. The safe docking locations can then be provided as goals to an autonomous path planner, within the context of providing adaptive driving assistance for powered wheelchair users. We evaluate the performance of our algorithm with systematic testing on several docking structures, observed from varied viewpoints.