Vehicle automatic transmission control system.

摘要

A system for controlling automatic transmissions equipped 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 the reserve motive force and engine output change that would occur should the current ratio be shifted to a given gear ratio. These measured and estimated values are put on a common scale named universe of discourse and membership values degree of the aforesaid rules are successively calculated. Among the rules, one rule is finally selected and according to a gear ratio indicated in the selected rule, the current gear ratio is shifted up or down or is held at the present ratio. In the system, some parameters are subjected to another fuzzy reasoning to determine the gear ratio to be shifted more suitably.