Effect of Virtual Object Material on the Pseudo-Haptic Weight

Haptic presentation technologies for virtual objects have garnered significant attention to improve the immersive ability of VR experiences. One such technology, the weight presentation of virtual objects, has applications in diverse fields, such as teleoperation and entertainment. Researchers have proposed various weight presentation methods using a haptic presentation technique called pseudo-haptics. The most common method involves setting the ratio of the displayed virtual object’s movement amount to that of the hand (C/D ratio) when lifting it. However, previous research has not thoroughly investigated how the appearance of virtual objects, such as their surface texture and material type, affects weight perception using pseudo-haptics. We conducted an experiment to allow participants to evaluate the perceived weights of 27 virtual objects. We manipulated the material type (polystyrene, wood, or metal) of the objects and the C/D ratios. The results showed that the dominant effect on the perceived weight when lifting a virtual object was due to the C/D ratio, whereas the effect of the material was relatively small (effect size of the C/D ratio: $\eta ^{2} =0.87$ , material: $\eta ^{2} =0.031$ ). The effect of C/D ratio was independent of the material used. These results indicate that the C/D ratio is more important than the material used when designing the weight of a virtual object using pseudo-haptics.