Seite - 58 - in Proceedings of the OAGM&ARW Joint Workshop - Vision, Automation and Robotics

Fig. 2. Connections between robot and hardware components to operate the robot through rough terrain, detect objects of interestsand interactwith them.Thefollowingblockdiagram (Fig. 2) shows connections between sensor components and the robot. The single cameras of the Robot are located on different points, giving the operator the possibility to obtain a broad view around the robot. Two cameras on the front and rear are placed in the body between the tracks, each giving a view in the needed driving direction. Another camera is positioned either on the left or right side of the front, giving the possibility to reconfigure and choose the needed side view before operating manually. A last camera is mounted to the last joint of the robot’s arm providing a view from the hooks position (e.g. view top-bottom, to see the tracks and the driveway in overview). Two laser scanners placed in the front are needed for generating maps and position in the operation via SLAM- algorithms. The nuclear sensor and the GPS module are applied for positioning and obtaining radiation heat maps. The stereo vision system is installed on the front of the robot. Its purpose is dedicated to future development of 3D map generation and autonomous operation. III. TELE-OPERATING MODE To control the robot manually, a tele-operating mode is implemented using ROS. One criteria is to provide two variants for the operator, which can be chosen later. These two steering variants are: • Keyboard controlled steering • Steering by Xbox controller For realisation of both steering variants various ROS packages were integrated in the software environment. TABLE I KEYBOARD BUTTON CONFIGURATION Button Function u Left rubber track forwards (right turn) i Go forward o Right rubber track forward (left turn) j Left rotation k Current command stop l Right rotation m Left rubber track backwards (right turn) , Go backward . Right rubber track backwards (left turn) A. Keyboard control First approach is to control the robot by a keyboard. To realise this variant, the teleop twist keyboard package [4] was integrated into the ROS environment. This allows the operator to control the vehicle with the input buttons shown in Table I. To quit operating the robot by the keyboard, CTRL- C has to be entered. After that the robot stays in safety state and cannot be controlled by keyboard as long as the teleop twist keyboard package is restarted. B. Xbox controller Alternatively, ROS also provides controlling the robot by Xbox controller [7]. Therefore, the joy package [6] is used for implementing the controller into the ROS environment. After implementation, every steering command of the robot can be used to configure it to one of the Xbox controllers or joysticks buttons. In Fig. 4 the wired Xbox controller and its buttons are demonstrated. Since there are only a few of control commands, not all 58