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Apparatus for detecting road surface frictional coefficient

Assignee: Toyota Motor Corp
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Filing: 1991-03-08
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Granted: 1993-07-20
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Expires: 2011-03-08
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Abstract

Abstract A detecting apparatus for detecting a frictional coefficient of the road surface on which an automotive vehicle travels. In the detection apparatus, a plurality of condition amounts related to at least one of the vehicle in braking operation, turning operation and a weather condition during travel of the vehicle are detected. Fuzzy inference is carried out on the detected conditional amounts to determine the compatibility of road surface frictional coefficients corresponding with the detected condition amounts. The fuzzy inference outputs are used to calculate a road surface frictional coefficient.

Inventors

  • 👤 Masaaki Nishiwaki
  • 👤 Hiroshi Harada
  • 👤 Hisanori Kaneko

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 08:00
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/174; B60G; B60G17/00; B60G17/015; B60G17/018; B60G17/0182; B60G17/0195; B60K; B60K31/00; B60T8/172; B62; B62D; B62D6/00; B62D7/00; B62D7/06; B62D7/14; B62D7/15; B62D7/159; B60G2400/00; B60G2400/10; B60G2400/20; B60G2400/204; B60G2400/208; B60G2400/25; B60G2400/252; B60G2400/40; B60G2400/41; B60G2400/50; B60G2400/60; B60G2400/61; B60G2400/80; B60G2400/82; B60G2400/822; B60G2400/84; B60G2400/842; B60G2400/8422; B60G2400/843; B60G2500/00; B60G2500/30; B60G2600/00; B60G2600/18; B60G2600/187; B60G2600/1879; B60G2800/00; B60G2800/01; B60G2800/012; B60G2800/014; B60G2800/21; B60G2800/24; B60T2210/00; B60T2210/10; B60T2210/12; B60T2210/122; B60T2260/00; B60T2260/02; B60T2260/022; Y; Y10; Y10S; Y10S706/00; Y10S706/90

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 104 words
A detection apparatus for detecting a frictional coefficient of a road surface on which an automotive vehicle travels, comprising: detecting means for detecting conditional parameters, the conditional parameters being at least a hydraulic pressure applied to a power cylinder of a power assisted steering apparatus of the vehicle and a lateral acceleration acting on the vehicle; fuzzy inference means for performing a fuzzy inference on the detected conditional parameters to determine a compatibility value corresponding to each detected conditional parameter, each compatibility value relating to a road surface frictional coefficient; generating means for generating said road surface frictional coefficient based on the compatibility values.
Claim 2
Dependent Claim 104 words
A detection apparatus for detecting a frictional coefficient of a road surface on which an automotive vehicle travels, comprising: detecting means for detecting conditional parameters, the conditional parameters being at least a hydraulic pressure applied to a power cylinder of a power assisted steering apparatus of the vehicle and a lateral acceleration acting on the vehicle; fuzzy inference means for performing a fuzzy inference on the detected conditional parameters to determine a compatibility value corresponding to each detected conditional parameter, each compatibility value relating to a road surface frictional coefficient; generating means for generating said road surface frictional coefficient based on the compatibility values.
Claim 3
Dependent Claim 32 words
The detection apparatus of claim 1, wherein the generating means includes means for logically summing the compatibility values and means for determining the road surface frictional coefficient based on the logical sum.
Claim 4
Dependent Claim 25 words
The detection apparatus of claim 1, wherein the detecting means includes means for detecting longitudinal acceleration of the vehicle as one of said conditional parameters.
Claim 5
Dependent Claim 59 words
The detection apparatus of claim 1, wherein the detecting means includes means for detecting torque acting on a steering shaft of the vehicle as one of said conditional parameters and means for detecting an axial force acting on a lateral bar in operative connection with a set of wheels of the vehicle as another one of said conditional parameters.
Claim 6
Dependent Claim 35 words
The detection apparatus of claim 4, wherein the detecting means includes ratio means for determining a ratio of the detected torque to a centrifugal force acting on the vehicle as one of said conditional parameters.
Claim 7
Dependent Claim 48 words
The detection apparatus of claim 5, wherein the detecting means includes means for detecting a traveling speed of the vehicle; and the ratio means includes calculating means for calculating the centrifugal force based on said traveling speed of the vehicle and a steering angle of the steering shaft.
Claim 8
Dependent Claim 26 words
The detection apparatus of claim 3, wherein the detecting means includes means for detecting a yaw rate of the vehicle as one of said conditional parameters.
Claim 9
Dependent Claim 42 words
The detecting apparatus of claim 7, wherein the detecting means includes means for detecting front and rear wheel speeds of the vehicle; and means for determining a difference between the detected front and rear wheels speeds as one of said conditional parameters.
Claim 10
Dependent Claim 42 words
The detection apparatus of claim 3, wherein the detecting means includes means for detecting front and rear wheel speeds of the vehicle; and means for determining a difference between the detected front and rear wheels speeds as one of said conditional parameters.
Claim 11
Dependent Claim 32 words
The detecting apparatus of claim 9, wherein the detecting means includes means for determining a frequency of operation of an anti-skid control system of the vehicle as one of said conditional parameters.
Claim 12
Dependent Claim 38 words
The detecting means of claim 10, wherein the detecting means includes means for detecting a frequency of operation of a wiper of the vehicle, means for detecting humidity, and means for detecting ambient temperature as said conditional parameters.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-07-19 1997-01-18 1997-07-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-07-19 2001-01-18 2001-07-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-07-19 2005-01-18 2005-07-20 $7700.00 Window Closed / Lapsed

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