Mobile Terminals Haptic Interface: A Vibro-Tactile Finger Device for 3D Shape Rendering

As the increasing in popularity of mobile terminals, the research on the haptic rendering accessory becomes more and more essential. This paper presents the design and implement of a vibro-tactile device mounted on the finger that could interact with mobile terminals and provide vibro-tactile stimulus for 3D shape displaying. To generate distributed vibro-tactile stimulus, four piezoelectric actuators are settled around the finger. A force sensor is attached on the fingertip to gauge the active force during the interaction. The lateral force is calculated corresponding with the changes of gradient for 3D object and local surface orientation. When stroking across the virtual object, the lateral force in contact is simulated as the vibro-tactile stimulus. The distribution and intension of the vibro-tactile stimulus vary with the direction and amplitude of the lateral force. To evaluate the performance of the tactile display system of 3D shape, psychophysical experiment was carried out. Results showed that the device is effective to provide vivid tactile perception corresponding with different shape.