A Direct-drive Haptic Thimble for Fine Tactile Feedback in Virtual and Robotic Manipulation

In this work, we present a direct-drive approach applied to an haptic thimble based on soft actuated belts. Building on a previous gearmotor-based design, the method leverages direct transmission to enhance linearity and to extend the output bandwidth of the device, thereby enriching the rendering of dynamic tactile feedback. While the approach reduces the maximum achievable force, it enables wide-bandwidth interaction in a thin and lightweight form factor. We validate the device in a virtual reality manipulation experiment, where physical simulation requires careful pick-and-place of virtual cubes. We also propose a proof-of-concept implementation in a teleoperation setup, where the thimble is coupled with a robotic hand equipped with sensitive pressure-based fingertip sensors. Results in VR highlight the effectiveness of the feedback in reducing the average virtual indentation and improving repeatability of the fine manipulation task.