Flexible fuzzy logic control for collision-free manipulator operation

Robot path planning is an important part in the development of autonomous systems. Numerous strategies have been proposed in the literature regarding mobile robots but trajectory planning for manipulators is considerably more difficult since the entire structure can move and produce collisions with surrounding obstacles. This paper presents an original and robust solution that can be used for safe path planning for various manipulator arms working in cluttered environments. Path planning is executed in two steps. First, a global path is determined to guide the end effector using classical artificial potential fields, probabilistic datasets and multi-resolution occupancy grids. Then, a fuzzy logic controller performs a local tracking for the entire robot structure by considering the kinematics of the robot as well as repulsive forces originating from nearby obstacles. Experimentation with robots of various architectures and different environments demonstrated the robustness and flexibility of the proposed planning and control approach which requires minimal tuning.