公开(公告)号：JP2001183250A

公开(公告)日：2001-07-06

申请号：JP36689799

申请日：1999-12-24

Applicant: NAT AEROSPACE LAB

Inventor： UEDA TETSUHIKO ,  SOTOZAKI TOKUO ,  KAI TAKASHI

IPC: G01L5/00 ,  B60T8/172 ,  G01N19/02

Abstract: PROBLEM TO BE SOLVED: To provide a road surface friction measuring device capable of being easily mounted on a general automobile and measuring coefficients of friction of various road surfaces such as a road, a runway or the like with high accuracy. SOLUTION: This device has a spindle 5 removably connected to a wheel of a driving wheel 3 of an automobile, an oscillatable supporting arm 6 connected to the spindle, and a measuring ring rotatably supported by the supporting arm. The supporting arm 6 is provided with a vertical drag generating mechanism generating the vertical drag to be added to the self-weight of the measuring ring 8, a first detecting means for detecting the vertical drag received by the measuring ring from a road surface, a rotation transmitting mechanism for transmitting the rotation of the spindle to the measuring ring for producing the difference in peripheral speeds between the driving wheel and the measuring ring, and a second detecting means for detecting the rotational resistance received by the driving wheel from the road surface, and a coefficient of friction of the road surface is calculated by an operating means on the basis of detected values of these detecting means, and the self-weight of the measurer including the arm.

公开(公告)号：JPH046408A

公开(公告)日：1992-01-10

申请号：JP10912790

申请日：1990-04-25

Applicant: NAT AEROSPACE LAB

Inventor： YAMANE KOUSABUROU ,  SOTOZAKI TOKUO

IPC: G01B21/28 ,  G06G7/48

Abstract: PURPOSE:To compute the cross-sectional area of each groove by the simple method by detecting the difference between the output of the shape of the groove from a groove-size input part before movement and the output from a half-pitch moving part after the shape of the groove is moved by a half pitch. CONSTITUTION:A groove-size input part 1 receives the shapes of a plurality of grooves which are arranged in a comb pattern. A half-pitch moving part 2 moves the shape of each groove outputted from the input part 1 by a half pitch in the horizontal direction. Then a difference detecting part 3 detects the absolute value of the difference between the output from the input part 1 before the horizontal movement and the output from the moving part after the horizontal movement. A threshold-value setting part 4 sets the threshold value having the required size with respect to the output of the detecting part 3 so as to prevent the adverse effects which are caused when the heights of the crests on both sides are different and when the upper part of the crest is not flat. Integration is performed in an integrating part 5 only when the output of the detecting part 3 is higher than the threshold value which is set by the setting part 4. The integrated value is obtained as the cross-sectional area of the shape of the groove.