Autonomous control of robotic carton unloader

A robotic carton unloader (100) has right and left lower arms (120) of a robotic arm assembly (102), respectively pivotally attached at lower ends to a moving body (114) on opposite lateral sides of a conveyor system (110) passing therebetween. An upper arm assembly (128) has rear ends pivotally attached to the upper ends of the lower right arm and the lower left arm, respectively, for pivotal rotation about an upper arm axis that is perpendicular to the longitudinal axis of the conveyor system and parallel to the lower arm axis. A manipulator head (136) attached at the front end of the upper arm assembly engages cartons in a stack of cartons resting on the floor for movement to the conveyor system. The upper arm axis is held at a height such that cartons can be conveyed by the conveyor system without being obstructed by the robotic arm assembly when the manipulator head is unblocked. A lifter (140) attached between the moving body and a front portion (142) of the conveyor system reduces spacing below the car