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Haptic Interfaces

Last-modified: Sun, 19 Nov 2006 11:12:21 GMT (2709d)

Representation of Artificial Tactile Feeling

Representation of artificial tactile feeling has been placed emphasis as new technology to augment virtual reality technology, also as new communication media for remote robotic manipulation or Internet shopping.

We have been studying presentation methods for qualitative surface textures of objects, such as clothes. Our major strategy for tactile presentation is applying vibratory stimuli to fingers.

We also have been studying tactile information processing of humans in psycophysic, engineering and numerical computation methods.

Synthesizing Tactile Feelings by Selectively Stimulating Mechanoreceptor Classes

ICPFtactileDisplay2.GIFMultiple tactile feelings, such as pressure, roughness and friction feelings can be synthesized by ICPF tactile display, which we have developed and studied effective displyaing methods.

A device in left pictures replicates surface textures of objects including qualitative information by mechanically stimulating three receptor classes selectively. Activation of each class can be controlled using the device. Because each class has different frequency response characteristics and ICPF tactile display can produce superposed vibrations, each vibration activates each class.

Tactile Displaying Method in Response to Rubbing Motion

TactileDisplayRespectingTouchMotion.jpgWe are studying the relationships between rubbing motions and tactile represence. Rubbing motion cannot be ignored, discussing humans' natural touch. Therefore we are proposing tactile display methods in syncronization with hand motions.

The left figure illustrates our experimental setup, in which subjects virtually touch clothes.

Touch a 3D Staffed Pig in a Computer

VirtuallyTouch3DObject.JPGAs a demonstration of integrated technology studied in our laboratory, we developed a "touch a virtual pig" system. You can feel differences of clothes and rub it along its spherical nose or ears.

The system presents roughness, softness and friction feelings to fingers just by mechanically vibratory stimuli, which are controlled according to rubbing motions.

Finite Element Model of a Finger

fem_for_analysing_tactile_coding.JPGWe are studying the deformation of human fingers and activities of tactile mechanoreceptors, using finite element model. Human fingers are structurely complex that numerical analysis by finite element model is considered to be an appropriate approach.

The model represents human fingers' complex tissue, like layered structure, epidermal ridges and the allocation of receptors. Physical parameters of tissue are modeled to be similar to those of human fingers.

This technology can be a new analysis method for receptors' activities while microelectrodes used to be unique methods.