Abstract – Presented in this paper is an approach to realtime spatial reasoning for manipulative robotic tasks. When a service robot is requested to manipulate an object, it should determine the directions along which it can access and remove the object. The potential accessible directions for the object are retrieved from the object database. Then, spatial reasoning with the surrounding environment and the gripper geometry is invoked to verify the directions. The verification process mainly utilizes the visibility test of the commodity graphics hardware. Then, the directions along which both of the object and gripper are translated without colliding with the surrounding obstacles are computed using Minkowski sum and cube map of the graphics hardware. The access and removal directions are passed to the potential field path planning algorithm to determine the robot arm’s full path for accessing, removing and delivering the object. The experimental results show the feasibility of usi...