Vehicle automatic transmission control system

A system for controlling a gear ratio of an automatic transmission in a vehicle, comprising:

• first means for determining a value for operating conditions of the vehicle including degree of throttle opening, vehicle speed change in the vehicle speed and gear ratio currently engaged;
• second means for calculating driving resistance of the vehicle;
• third means for establishing a membership function of a fuzzy set of at least one of the determined values in accordance with a first set of at least one fuzzy production rule defining a respective conclusion for adjusting said driving resistance and for carrying out a first fuzzy reasoning based on said first set of fuzzy production rules to adjust the driving resistance;
• fourth means for calculating reserve motive force from the adjusted driving resistance;
• fifth means for establishing another membership function of a fuzzy set of at least one of the determined values an the calculated motive force value in accordance with a second set of fuzzy production rules defining respective gear ratio shifting conclusions and for carrying out a second fuzzy reasoning based on said second set of fuzzy production rules to determine a gear ratio to be engaged;
• and
• actuator means for driving a gear ratio shift mechanism in response to the determined gear ratio.

A system for controlling a gear ratio of an automatic transmission in a vehicle, comprising:

• first means for determining a value for operating conditions of the vehicle including degree of throttle opening, change in the degree of throttle opening, vehicle speed and gear ratio currently engaged;
• second means for establishing a membership function of a fuzzy set of at least of the determined values in accordance with a first set of at least one fuzzy production rule defining a respective conclusion for evaluating change in engine output power desired by the driver and for carrying out a first fuzzy reasoning based on said first set of fuzzy production rules to evaluate change in engine output power desired by the driver;
• third means for establishing another membership function of a fuzzy set of at least one of the determined values and the evaluated value in accordance with a second set of fuzzy production rules defining respective gear ratio shifting conclusions and for carrying out a second fuzzy reasoning based on said second set of fuzzy production rules to determine a gear ratio to be engaged;
• and
• actuator means for driving a gear ratio shift mechanism in response to the determined gear ratio.

A system for controlling a gear ratio of an automatic transmission in a vehicle, comprising:

• first means for determining a value for each operating condition of the vehicle including degree of throttle opening, vehicle speed, change in the vehicle speed and gear ratio currently engaged;
• second means for calculating a driving resistance of the vehicle;
• third means or establishing a membership function of a fuzzy set of at least one of the determined values and for carrying out a first fuzzy reasoning thereon to adjust the driving resistance;
• fourth means for calculating a reserve motive force from the adjusted driving resistance;
• fifth means for establishing another membership function of a fuzzy set of the determined values and the calculated motive force and for carrying out a second fuzzy reasoning to determine a gear ratio to be shifted to;
• and
• actuator mans for driving a gear ratio shift mechanism in response to the determined gear ratio;
• wherein said third means carries out the first fuzzy reasoning by selecting one of a plurality of fuzzy production rules by calculating a membership grade value of the rules and selecting one among the rules in which the grade value becomes maximum.

A system for controlling a gear ratio of an automatic transmission in a vehicle, comprising:

• first means for determining a value for each operating condition of the vehicle including degree of throttle opening, change in the degree of throttle opening, vehicle speed and gear ratio currently engaged;
• second means for establishing a membership function of a fuzzy set of at least one of the determine values and for carrying out a first fuzzy reasoning thereon to develop an evaluated value of any change in engine output power desired by the driver;
• third means for establishing another membership function of a fuzzy set of the determined values and the evaluated value and for carrying out a second fuzzy reasoning thereon to determine a gear ratio to be shifted to;
• and
• actuator means for driving a gear ratio shift mechanism in response to the determined gear ratio;
• wherein said second means carries out the first fuzzy reasoning by selecting one of a plurality of fuzzy production rules by calculating a membership grade value of the rules and selecting one among the rules in which the grade value becomes maximum.

A system for controlling a gear ratio of an automatic transmission in a vehicle, comprising:

• first means for determining a value for each operating condition of the vehicle including degree of throttle opening, change in the degree of throttle opening, vehicle speed and gear ratio currently engaged;
• second means for establishing a membership function of a fuzzy set of at least one of the determined values and for carrying out a first fuzzy reasoning thereon to develop an evaluated value of any change in engine output power desired by the driver;
• third means for establishing another membership function of a fuzzy set of the determined values and the evaluated value and for carrying out a second fuzzy reasoning thereon to determine a gear ratio to be shifted to;
• actuator means for driving a gear ratio shift mechanism in response to the determined gear ratio;
• fourth means for calculating a ratio between said evaluated value of any change in the engine output power desired by the driver and a value of engine output power estimated to be actually generated;
• and
• said third means establishing a membership function based on said ratio and carrying out the second fuzzy reasoning thereon.