Control apparatus for continuously variable transmission mounted in automotive vehicle

A control apparatus for an automotive vehicle, comprising:

• a) a continuously variable transmission, including a gear shift ratio varying mechanism and whose gear shift ratio is continuously controlled according to an operating variable of said gear shift ratio varying mechanism, said gear shift ratio varying mechanism being so arranged and constructed as to continuously vary the gear shift ratio of the continuously variable transmission according to a gear shift ratio command value;
• b) a first sensor which is so arranged and constructed as to detect a vehicle driving condition of the vehicle in which the continuously variable transmission is mounted;
• c) a second sensor which is so arranged and constructed as to detect an actual gear shift ratio of the continuously variable transmission;
• and
• d) a control unit having;
• e) a target gear shift ratio calculating block for calculating a target gear shift ratio on the basis of the detected vehicle driving condition;
• f) a dynamic characteristic estimating block for estimating a predetermined dynamic characteristic for each instantaneous gear shift ratio of the continuously variable transmission;
• g) a disturbance compensator which is so arranged and constructed as to calculate a disturbance compensation output as functions of the actual gear shift ratio and of either the gear shift ratio command value or the operating variable of the gear shift ratio varying mechanism;
• h) a gear shift ratio control constant calculating block for calculating a control constant of each instantaneous gear shift ratio of the continuously variable transmission so as to achieve a target dynamic characteristic using the estimated dynamic characteristic;
• i) a first gear shift ratio command calculating block for calculating a first gear shift ratio command value from the target gear shift ratio, the actual gear shift ratio, and the control constant of the corresponding instantaneous gear shift ratio;
• and
• j) a second gear shift ratio command calculating block for subtracting the disturbance compensation output of the disturbance compensator from the first gear shift ratio command value so as to derive and output the gear shift ratio command value,
• and the control apparatus further comprising;
• k) a gear shift ratio control block for adjustably controlling the operating variable of the gear shift ratio varying mechanism as the function of the output gear shift ratio command value.