Comparison of kinesthetic and skin deformation feedback for mass rendering

Abstract

Virtual and augmented reality systems that immerse users in a 3D environment could benefit from haptic (force and/or tactile) feedback to increase realism and task performance. A canonical task that cannot be achieved compellingly without haptic feedback is the grasp and lift of an object with mass. Traditional kinesthetic (force) feedback devices provide realistic physical interactions with virtual objects, but typically require large actuators, making them bulky and encumbering. In contrast, tactile feedback devices can use smaller actuators and may enable freer movement of a user in a virtual world. One form of tactile feedback, skin deformation feedback, has been previously shown to provide effective haptic feedback of force, stiffness, and friction. Here we compare human perception of mass via kinesthetic feedback and skin deformation feedback in a virtual environment. Participants grasp and lift two virtual blocks and attempt to equalize their masses by the method of adjustments. From the accuracy of this equalization, we determined that the Weber Fraction (the just noticeable difference in proportion to the original stimulus value) of virtual mass during a grasp and lift task was 0.11 for kinesthetic force feedback and 0.35 for skin deformation feedback. In addition, participants exhibited differences in exploratory procedures between the two types of feedback.