Engine controller

An engine controller to control an injection quantity injected into a cylinder of an engine mounted on a vehicle or an intake airflow supplied to a cylinder of an engine corresponding to an accelerator operation amount, comprising:

• a vehicle specifications administrator capable of reconfiguring one or more constants based on vehicle specifications such as an air resistance coefficient determined by the vehicle's overall shape, the vehicle's frontal projected area, an effective tire radius, or a final gear ratio when a change is made to the vehicle specifications associated with an increase or a decrease in a running resistance of the vehicle;
• a target speed calculator for determining a target running speed from the driver's accelerator operation amount and air resistance calculator for determining an air resistance using the target running speed, a constant based on the air resistance coefficient, and a constant based on the frontal projected area;
• a running resistance calculator for adding at least a rolling resistance to the air resistance to determine a running resistance for constant running of the vehicle at the target running speed;
• a driving wheel torque calculator for determining a driving wheel torque using the running resistance and a constant based on the effective tire radius;
• and
• a transmission output shaft torque calculator for determining an engine output shaft torque equivalent to a driver-requested torque using the driving wheel torque and a constant based on the final gear ratio.

A method of controlling an injection quantity or intake airflow supplied to a cylinder of an engine mounted on a vehicle, comprising:

• reconfiguring one or more constants associated with an increase or a decrease in a running resistance of the vehicle, the constants being based on vehicle specifications;
• determining a target acceleration from an accelerator operation amount;
• determining an acceleration resistance based on the target acceleration and a constant related to the vehicle weight;
• adding at least an air resistance and a rolling resistance to the acceleration resistance to determine a running resistance for running of the vehicle at the target acceleration;
• determining a driving wheel torque based on the running resistance and a constant related to the effective tire radius;
• and
• determining an engine output shaft torque equivalent to a driver-requested torque based on the driving wheel torque and a constant related to the final gear ratio.