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Robotic teleoperators introduce novel electrome- chanical dynamics between the user and the environment. While considerable effort has focused on minimizing these dynamics, we lack a robust understanding of their impact on user task per- formance across the range of human motor control ability. Here, we utilize a 1-DoF teleoperator testbed with interchangeable mechanical and electromechanical couplings between the leader and follower to investigate to what extent, if any, the dynamics of the teleoperator influence performance in a visual-motor pursuit tracking task. We recruited N = 30 participants to perform the task at frequencies ranging from 0.55 - 2.35 Hz, with the testbed configured into Mechanical, Unilateral, and Bilateral configu- rations. Results demonstrate that tracking performance at the follower was similar across configurations. However, participants’ adjustment at the leader differed between Mechanical, Unilateral, and Bilateral configurations. In addition, participants applied different grip forces between the Mechanical and Unilateral configurations. Finally, participants’ ability to compensate for coupling dynamics diminished significantly as execution speed increased. Overall, these findings support the argument that humans are capable of incorporating teleoperator dynamics into their motor control scheme and producing compensatory control strategies to account for these dynamics; however, this compensation is significantly affected by the leader-follower coupling dynamics and the speed of task execution. 

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.