3D Shape Presentation by Combination of Force Feedback and Electro-tactile Stimulation

The rapid and precise understanding of 3D objects in virtual reality environment is crucial for proficient manipulation of virtual objects. Generally, relying solely on a force feedback device falls short in conveying intricate shapes, such as the edges of 3D objects, and it is deemed necessary to supplement it with appropriate cutaneous sensory inputs. Electrotactile stimulation, owing to its compact and lightweight design, has the potential to provide high-resolution cutaneous sensory inputs and could be a viable method for presenting intricate shapes when incorporated with a force feedback device. In this research, we devised a system that concurrently presents cutaneous inputs along the object's edge through electrical stimulation, as well as reactive force from the object through a force feedback device, and evaluated its impact on 3D shape perception under three scenarios: force feedback alone, cutaneous feedback alone, and combined sensory presentation. The results from experiments on the identification of four types of column shapes in single-finger contact and two-fingers grasping indicate that the combined presentation of force and electro-tactile sensation significantly hastens the differentiation time of the shapes and facilitates more efficient recognition of 3D objects.