In virtual reality, virtual weight perception allows users to perform tasks more precisely and enhances immersion.In this paper, we propose a variable offset (VO) method based on a fivefinger pressure input technique and combines it with visual and haptic feedbacks to enhance virtual weight perception.The VO method integrates a haptic controller that can capture forces applied by five fingers with a control/display ratio control scheme.When a user grabs a virtual object using all five fingers, a semitransparent duplicate of the object appears below the original, and VO between the two is adjusted dynamically on the basis of the objects weight and force applied by the user.To reinforce this perception, visual cues, e.g., dynamic lines and outline changes, and vibrotactile feedback are incorporated during the object manipulation task.In an experiment, participants were asked to arrange four cubes by increasing weight.Two comparative experiments were designed to evaluate differences in the visual and haptic feedback techniques based on the proposed VO method.Quantitative measures, i.e., task completion time and accuracy, were collected, and questionnaire-based qualitative assessments were performed.Results showed that connecting lines between objects improved performance over outline emphasis and other conditions.For haptics, continuous vibration based on force and weight outperformed single vibration based on weight alone and received higher immersion ratings.
Ha et al. (Mon,) studied this question.