The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 23, 2001
Filed:
Jul. 28, 1999
Hiroyuki Yamaguchi, Aichi, JP;
Katsuhiro Asano, Aichi, JP;
Kenji Tozu, Mie, JP;
Takayuki Itoh, Aichi, JP;
Akitaka Nishio, Aichi, JP;
Other;
Abstract
A vehicle running condition judgment device for accurately detecting a change in a road surface condition and a vehicle's limit running condition. With substitution of respective tire characteristics and a detected state quantity into a vehicle motion model, vehicle slip angles are estimated for respective assumed road surface conditions. Based on the current state quantity and the last estimated vehicle slip angle, currently estimated vehicle slip angles for the respective assumed road surface conditions are compensated. A differential operation section calculates an estimation value of a vehicle slip angular velocity for each of the assumed road surface conditions based on the compensated vehicle slip angles for the respective assumed road surface conditions. Meanwhile, an operation section calculates a detection value of a vehicle slip angular velocity based on the detected state quantity. By comparing the detection value and the respective estimation values for the assumed road surface conditions, the current road surface condition is determined. Further, a lateral acceleration is calculated based on a vehicle slip angle, and compared with the detection value for determination of the road surface condition, and also with a predetermined limit value for determination of a vehicle's limit running condition.