Vehicle automatic transmission control system
US5079704A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1989 |
| Grant date | Jan 7, 1992 |
| Priority date | — |
| Expiry date | Nov 20, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S706/90
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A system for controlling automatic, multi-step or continuously variable, transmission equipped with a motor vehicle utilizing fuzzy logic. In the system, fuzzy production rules have been prepared based upon an expert driver's judgments and operation made on a vehicle with a manually shifted transmission. Various operating conditions including opening degree of a throttle valve and road speed of the vehicle are detected and from the detected value, various predictions are made such as an appropriateness of vehicle response determined from the reserve motive force with respect to a gear ratio shift intended by the driver and engine output change that would occur should the transmission be shifted to the gear ratio. These measured or estimated value are put on a common scale named universe of discourse and membership values of the rules are sucessively calculated. Among the rules, one rule is finally selected and according to the gear ratio indicated in the selected rule, the current gear ratio is shifted up or down or is held at the present ratio. Similarly, the speed ratio in the continuously variable transmission is determined from the selected rule.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.