Patent ID: 7257522

Claim:
A simulator system having computer-aided design programs for simulating a shift control algorithm for an automatic transmission of a vehicle having a hydraulic actuator to transmit power generated by an internal combustion engine to drive wheels in accordance with the shift control algorithm, comprising: a control system design tool for inputting the shift control algorithm and for outputting a hydraulic pressure supply command as a pseudo signal such that the hydraulic pressure supply command is supplied to the hydraulic actuator through a hydraulic circuit based on a shift signal from the shift control algorithm; a first simulator section connected to the control system design tool for inputting the hydraulic pressure supply command and for estimating an effective hydraulic pressure generated in the hydraulic actuator in response to the hydraulic pressure supply command based on a first model; a second simulator section connected to the control system design tool and to the first simulator section for determining transfer functions of a second model describing behavior of the hydraulic actuator such that an output of the second model converges with the estimated effective hydraulic pressure; and a third model obtained by incorporating the second model with the first model, wherein the second simulator section simulates and evaluates the shift control algorithm based on the third model.