|A sensor system
measuring the surface pattern of objects by using a spatial filtering tactile
sensor. The sensor has a band-pass spatial filtering function and changes its
center of spatial frequency with the tactile motion. The idea of this method
is based on the nervous system in human finger.
It is said that cutaneous receptors exist by 50 pieces per 1 mm2 at the tip of a human finger and nervous units are distributed 1 unit per 1 mm2 . As the result, (1) the cutaneous receptors construct a spatial filter and signals from them are summed within the nervous unit. (2) In the touch motion performed by a man, the delay of the signal transmission through nervous unit and touch motion velocity changes the spatial filtering characteristic to make the spatial resolution higher.
This sensor system is characterized by (1) robust measurement system for non-uniform contact state and (2) adaptable for a wide spatial frequency range in the surface pattern of objects. And high spatial resolution can be realized.