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Humans possess an innate ability to incorporate tools into our body schema to perform a myriad of tasks not possible with our natural limbs. Human-in-the-loop telerobotic systems (HiLTS) are tools that extend human manipulation capabilities to remote and virtual environments. Unlike most hand-held tools, however, HiLTS often possess complex electromechanical architectures that introduce non-trivial transmission dynamics between the robot’s leader and follower, which alter or obfuscate the environment’s dynamics. While considerable research has focused on negating or circumventing these dynamics, it is not well understood how capable human operators are at incorporating these transmission dynamics into their sensorimotor control scheme. To begin answering this question, we recruited N=12 participants to use a novel reconfigurable teleoperator with varying transmission dynamics to perform a visuo-haptic tracking task. Contrary to our original hypothesis, our findings demonstrate that humans can account for substantial differences in teleoperator transmission dynamics and produce the compensatory strategies necessary to adequately control the teleoperator. These findings suggest that advances in transparency algorithms and haptic feedback approaches must be coupled with control designs that leverage the unique capabilities of the human operator in the loop. 

Haptic illusions provide unique insights into how we model our bodies separate from our environment. Popular illusions like the rubber-hand illusion and mirror-box illusion have demonstrated that we can adapt the internal representations of our limbs in response to visuo-haptic conflicts. In this manuscript, we extend this knowledge by investigating to what extent, if any, we also augment our external representations of the environment and its action on our bodies in response to visuo-haptic conflicts. Utilizing a mirror and a robotic brushstroking platform, we create a novel illusory paradigm that presents a visuo-haptic conflict using congruent and incongruent tactile stimuli applied to participants' fingers. Overall, we observed that participants perceived an illusory tactile sensation on their visually occluded finger when seeing a visual stimulus that was inconsistent with the actual tactile stimulus provided. We also found residual effects of the illusion after the conflict was removed. These findings highlight how our need to maintain a coherent internal representation of our body extends to our model of our environment. 

The utility of telerobotic systems is driven in large part by the quality of feedback they provide to the operator. While the dynamic interaction between a robot and the environment can often be sensed or modeled, the dynamic coupling at the human-robot interface is often overlooked. Improving dexterous manipulation through telerobots will require careful consideration of human haptic perception as it relates to human exploration dynamics at the telerobotic interface. In this manuscript, we use exploration velocity as a means of controlling the operator's exploration dynamics, and present results from two stiffness discrimination experiments designed to investigate the effects of exploration velocity on stiffness perception. The results indicate that stiffness percepts vary differently for different exploration velocities on an individual level, however, no consistent trends were found across all participants. These results suggest that exploration dynamics can affect the quality of haptic interactions through telerobotic interfaces, and also reflect the need to study the underlying mechanisms that cause our perception to vary with our choice of exploration strategy.