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.
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Prefatory study of the effects of exploration dynamics on stiffness perception
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.
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- Award ID(s):
- 1657245
- NSF-PAR ID:
- 10206030
- Date Published:
- Journal Name:
- 2020 IEEE Haptics Symposium
- Page Range / eLocation ID:
- 128 to 133
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/HAPTICS45997.2020.ras.HAP20.31.f7ecf8e2
