PURPOSE: To reduce the analysis time and labor by enabling a frequency analysis of noise of a vehicle on real time with due outputting thereof when it runs at a specified pattern while fully automatizing the operations to the output of the analysis result and the grade evaluation from the measurement of noise.
CONSTITUTION: A vehicle speed signal from a set vehicle speed detection circuit 40 is supplied to a data table 34 together with a frequency spectrum from a frequency analyzer 24. The set vehicle speed detection circuit 40 memorizes a frequency spectrum only when the speed of the actually running vehicle is within a specified vehicle speed based on the vehicle speed signal obtained from the comparison the set vehicle speed inputted from an operation keyboard or the like in an output section 12 with the speed of the actually running vehicle from a vehicle sensor 22 to average the spectrum at the same vehicle speed. A maximum value processing for determining the maximum value for respective vehicle speeds within the repetition frequency and a averaging computation for determining mean for respective vehicle speeds in the repeated running analysis are executed by a program of a microcomputer 32 to obtain a graph for the vehicle speed and the noise level.
FUKAMACHI MITSUO
NOBORI HIROSHI
MATSUSHITA ELECTRIC IND CO LTD
| JPS5582020A | 1980-06-20 |