Haptic communication for remote mobile and manipulator robot operations in hazardous environments

Abstract

Nuclear decommissioning involves the use of remotely deployed mobile vehiclesand manipulators controlled via teleoperation systems. Manipulators are used fortooling and sorting tasks, and mobile vehicles are used to locate a manipulatornear to the area that it is to be operated upon and also to carry a camera into aremote area for monitoring and assessment purposes.Teleoperations in hazardous environments are often hampered by a lack of visualinformation. Direct line of sight is often only available through small, thickwindows, which often become discoloured and less transparent over time. Idealcamera locations are generally not possible, which can lead to areas of the cell notbeing visible, or at least difficult to see. Damage to the mobile, manipulator, toolor environment can be very expensive and dangerous.Despite the advances in the recent years of autonomous systems, the nuclearindustry prefers generally to ensure that there is a human in the loop. This is dueto the safety critical nature of the industry. Haptic interfaces provide a meansof allowing an operator to control aspects of a task that would be difficult orimpossible to control with impoverished visual feedback alone. Manipulator endeffectorforce control and mobile vehicle collision avoidance are examples of suchtasks.Haptic communication has been integrated with both a Schilling Titan II manipulatorteleoperation system and Cybermotion K2A mobile vehicle teleoperationsystem. The manipulator research was carried out using a real manipulatorwhereas the mobile research was carried out in simulation. Novel haptic communicationgeneration algorithms have been developed. Experiments have beenconducted using both the mobile and the manipulator to assess the performancegains offered by haptic communication.The results of the mobile vehicle experiments show that haptic feedback offeredperformance improvements in systems where the operator is solely responsible forcontrol of the vehicle. However in systems where the operator is assisted by semiautonomous behaviour that can perform obstacle avoidance, the advantages ofhaptic feedback were more subtle.The results from the manipulator experiments served to support the results fromthe mobile vehicle experiments since they also show that haptic feedback does notalways improve operator performance. Instead, performance gains rely heavily onthe nature of the task, other system feedback channels and operator assistancefeatures. The tasks performed with the manipulator were peg insertion, grindingand drilling