Behavior-Based Collision Avoidance Using a Cylinder-Coordinate Octree

The research at hand is part of the autonomous excavator project Thor. The long term-goal is the development of an excavator which is capable of performing landscaping tasks without human intervention. As this machine creates huge forces, safety plays an important role. This research extends the behavior-based trajectory generation for the excavation and truck loading operation, working for the undisturbed case only, with collision avoidance concerning obstacles and the machine itself. Based on a data efficient cylinder-coordinate octree for storing obstacles, joint movements are inhibited or actively influenced to prevent the machine from hitting objects and itself. Additionally, this research shows the suitability of the extensible reactive behavior-based control approach for the automation of construction machines.