Analysis of MR–VR tele-operation methods for legged-manipulator robots

The development of immersive technologies in recent years has facilitated the control and execution of tasks at a high level of complexity in robotic systems. On the other hand, exploration and manipulation tasks in unknown environments have been one of the main challenges in search and rescue (SAR) robotics. Due to the complexity and uncertainty involved in autonomous manipulation tasks in unstructured environments, these are usually tele-operated initially. This article addresses a comparative study between Mixed Reality (MR—Hololens) and Virtual Reality (VR—HTC-Vive) methods for teleoperating legged-manipulator robots in the context of search and rescue. For this purpose, a teleoperation robotics method was established to address the comparison, developing VR–MR interfaces with the same contextualization and operational functionality for mission management and robot control of a robotic set composed of a quadrupedal robot equipped with a 6 degrees of freedom (6DoF) manipulator, by a user using hand gestures. A set of metrics is proposed for the comparative evaluation of the interfaces considering parameters that allow analyzing operability in the context of the mission (latencies, physical parameters of the equipment, etc.), as well as from the aspect of operator performance (required training, confidence levels, etc.). The experimental phase was conducted using both on-site and remote operations to evaluate and categorize the advantages and disadvantages of each method.