Slip-Grip: An Electrotactile Method to Simulate Weight

Weight perception is crucial for immersive virtual reality (VR) interactions, yet providing weight feedback remains a significant research challenge. We introduce a novel weight simulation technique that leverages electrotactile stimulation to induce slip illusions. These slip illusions occur when users grip an object with less force than a predefined threshold, allowing the device to modulate the grip force and encourage a tighter grip. In our approach, heavier virtual weights correspond to higher required grip forces. We conducted a series of user experiments to validate our technique, confirming that it effectively induces slip illusions. We also investigated the relationship between electrotactile sensations and grip force, and changes in force, demonstrating that this association enhances the weight perception experience. Lastly, we explored the mapping between grip force and perceived weight, observing strong linearity within participants but notable variability between individuals.