11 March 2009—A few years from now, young Jane, returning home from a school trip to the Smithsonian, might excitedly tell her mom, ”Guess what? I touched the Hope Diamond today,” while brother John shouts, ”That’s nothing! I touched a Neanderthal skull.” These are the kind of scenarios Hiroaki Yano, associate professor in the department of intelligent interaction technologies at the University of Tsukuba, Japan, is working to realize.
Yano, 39, has spent the past 15 years (including obtaining his Ph.D. in engineering) working in the field of haptics, the study of sensing and manipulation of objects through touch. For the past year he has led a research group developing a handheld haptic device for sensing unreachable or untouchable objects and is due to report details of the device next week at the IEEE-sponsored 2009 World Haptics Conference in Salt Lake City.
The prototype system employs a laser range finder to determine the distance to a given object. The data are fed to a computer, where an algorithm calculates the motor torque necessary to move a lever backward and forward in real time on a haptic interface device; the degree of movement corresponds to the changing distance the laser beam measures as it tracks across the surface of the object. By pressing a thumb against the moving lever, the user can feel the reaction force generated by the object and so get a sense of its shape, even down to changes in surface depth as fine as 0.1 millimeter. The device works for a distance up to 1 meter and through glass.
To evaluate how well the device works, Yano had six participants use it see if they could identify which of four unseen objects were placed in front of them: a forward-facing cube, a sphere, a cylinder, or a cube with only one edge facing forward. Each participant was tested four times with each object, for a total of 16 tries. The experiment was carried out with a glass barrier placed in front of the objects.
”The result was amazing,” says Yano. ”All participants got the sphere and the cube plane correct every time. Only one participant failed one time to identify the cylinder, and there were two failures in identifying the cube placed edge forward. That’s a 96 percent success rate.”