Continuous VR Weight Illusion by Combining Adaptive Trigger Resistance and Control-Display Ratio Manipulation

Handheld virtual reality (VR) controllers enable users to manipulate virtual objects in VR but do not convey a virtual object's weight. This hinders users from effectively experiencing lighter and heavier objects. While previous work explored either hardware-based interfaces or software-based pseudo-haptics, in this paper, we combine two techniques to improve the virtual weight perception in VR. By adapting the trigger resistance of the VR controller when grasping a virtual object and manipulating the control-display (C/D) ratio during lifting, we create a continuous weight sensation. In a psychophysical study (N=29), we compared our combined approach against the individual rendering techniques. Our results show that participants were significantly more sensitive towards smaller weight differences in the combined weight simulations compared to the individual methods. Additionally, participants were also able to determine weight differences significantly faster with both cues present compared to the single pseudo-haptic technique. While all three techniques were generally valued to be effective, the combined approach was favoured the most. Our findings demonstrate the meaningful benefit of combining physical and virtual techniques for virtual weight rendering over previously proposed methods.