Design and Evaluation of a Wearable Haptic Device for Skin Stretch, Pressure, and Vibrotactile Stimuli

Abstract

Abstract-This paper presents a wearable haptic device for the forearm and its application in robotic teleoperation. The device is able to provide skin stretch, pressure, and vibrotactile stimuli. Two servo motors, housed in a 3D printed lightweight platform, actuate an elastic fabric belt, wrapped around the arm. When the two servo motors rotate in opposite directions, the belt is tightened (or loosened), thereby compressing (or decompressing) the arm. On the other hand, when the two motors rotate in the same direction, the belt applies a shear force to the arm skin. Moreover, the belt houses four vibrotactile motors, positioned evenly around the arm at 90 degrees from each other. The device weights 220 g for 115×122×50 mm of dimensions, making it wearable and unobtrusive. We carried out a perceptual characterization of the device as well as two human-subjects teleoperation experiments in a virtual environment, employing a total of 34 subjects. In the first experiment, participants were asked to control the motion of a robotic manipulator for grasping an object; in the second experiment, participants were asked to teleoperate the motion of a quadrotor fleet along a given path. In both scenarios, the wearable haptic device provided feedback information about the status of the slave robot(s) and of the given task. Results showed the effectiveness of the proposed device. Performance on completion time, length trajectory, and perceived effectiveness when using the wearable device improved of 19.8%, 25.1%, and 149.1% than when wearing no device, respectively. Finally, all subjects but three preferred the conditions including wearable haptics.

Haptic Shared-Control Methods for Robotic Cutting under Nonholonomic Constraints

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A pilot study on locomotion training via biomechanical models and a wearable haptic feedback system

“…Alonzo et al proposed stacking vibrotactile stimulators on top of electrotactile stimulators to make the system more compact [36]. Another wearable haptic device could deliver skin-stretch, pressure, and vibrotactile to convey information about the status of the teleoperated robot and it has been shown to effectively improve the user operation performance [37]. Skin stretch is a natural sensing mode for proprioception, thus making it ideal to intuitively convey proprioceptive information to the user [25], even when compared to vibrotactile feedback [38].…”

Combining Wearable Finger Haptics and Augmented Reality: User Evaluation Using an External Camera and the Microsoft HoloLens

“…Specifically, we will study more in detail the effect of vibrotactile stimuli in AR, and we will consider haptic devices for the wrist and arm (e.g., [27], [28]). Finally, we intend to better investigate the role of sensory substitution of visual feedback, combining visual and haptic information together to achieve higher performance.…”