Coloration is a phenomenon in which timbre changes when reflected and direct sounds are mixed. We studied the relationship between the perception of coloration and direction for two sounds. Our psychological experiments using 11 subjects suggested that a 50% threshold of coloration appears to have no difference depending on direction. When the level ratio of two sounds is closer to 0 dB, a difference appears: If direct sound comes from a lateral direction and reflected sound comes from the opposite direction, coloration perception does not increase monotonically even if the ratio approaches 0 dB. We assumed that the difference depending on direction resulted from the directional dependence of the spectrum including the head-related transfer function (HRTF) and proposed a numerical model for predicting psychological results using the comb structure on the spectrum observed at the eardrum. We measured spectra using a head and torso simulator (HATS) and calculated the area, eventually finding a quantitative relationship between the area and psychological results and proposing a prediction model based on this relationship.

This paper describes a measurement system that can simultaneously measure the distribution of grasping pressure, grasping posture and wrist position synchronously with grasping action video image data. A sensor designed to measure the distribution of grasping pressure was developed, for use with this system, and when employed, it is slipped onto the hand the same way as an ordinary glove. It has 15 load detection points on each finger and a total of 81 such points for a single hand. A sensor that can detect finger movements at 18 joints was used, for the measurement of the grasping posture and wrist position. This paper discusses the configuration of the system and presents an experimental result.