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Drone application for aerial manipulation is tested in such areas as industrial maintenance, supporting the rescuers in emergencies, and e-commerce. Most of such applications require teleoperation. The operator receives visual feedback from the camera installed on a robot arm or drone. As aerial manipulation requires delicate and precise motion of robot arm, the camera data delay, narrow field of view, and blurred image caused by drone dynamics can lead the UAV to crash. The paper focuses on the development of a novel teleoperation system for aerial manipulation using Virtual Reality (VR). The controlled system consists of UAV with a 4-DoF robotic arm and embedded sensors. VR application presents the digital twin of drone and remote environment to the user through a headmounted display (HMD). The operator controls the position of the robotic arm and gripper with VR trackers worn on the arm and tracking glove with vibrotactile feedback. Control data is translated directly from VR to the real robot in realtime. The experimental results showed a stable and robust teleoperation mediated by the VR scene. The proposed system can considerably improve the quality of aerial manipulations.

Abstract:A fine-grained Ti-6Al-4V sheet that has been developed for superplastic forming was joined to a standard Ti-6Al-4V sheet using a Nd:YAG laser and alloy compatible filler wire. The microstructural and mechanical properties of dissimilar laser beam welded butt joints were investigated to determine their behaviour under static and cyclic loads and for superplastic forming. The filler wire affected the heat input and reduced the increase in the hardness within the fusion zone compared to that in the heat-affected zone. Moreover, the laser beam welding process activated local microstructure transformations that were associated with local changes in the microtexture, the  content and the grain size. The mechanical behaviour of a dissimilar laser beam welded butt joint under a static tensile load was controlled by the properties of the standard Ti-6Al-4V sheet. It is well known that geometrical notches affect fatigue behaviour, and fatigue fracture usually occurs within the heat-affected zones adjacent to the welding seam. However, removing the geometrical notches did not significantly improve the fatigue behaviour because local microstructural and microtextural changes still created metallurgical notches. Superplastic forming was observed in the fine-grained Ti-6Al-4V sheet without crack formation in the heat-affected zones or the fusion zone. The welding seam of the dissimilar fine-grained-standard butt joint was resistant to superplastic forming.

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