Autonomous Mission with a Mobile Manipulator - A Solution to the MBZIRC.

This work presents the system and approach we employed to tackle the second challenge of the Mohamed Bin Zayed International Robotics Challenge (MBZIRC) (See http://www.mbzirc.com/challenge). The goal of this challenge is to find a tool panel on a field, pick an appropriate wrench from the panel, and operate a valve stem therewith. For this purpose we use a task-oriented field robot, based on Clearpath Husky with a customized series elastic arm, that can be deployed for versatile purposes. However, to be competitive in a robotic challenge, further specialization and improvements are necessary to achieve a certain task faster and more reliably. A high emphasis is put on designing a system that can operate fully autonomously and independently respond if a subtask was not executed successfully. Moreover, the operator can easily monitor the system through a graphical user interface and, if desired, interact with the robot. We present our algorithms to explore the field, detect the panel, and navigate to it. Furthermore, we use a support vector machine based object detection method to locate the valve stem and wrenches on the panel for visual servoing. Finally, we show the advantages of a force controllable manipulator to handle the valve stem with a tool. This system demonstrated its applicability when fulfilling the entire task fully autonomously during both trials of the Grand Challenge of the MBZIRC 2017.