Controller and control method

1 . A controller which is a controller that performs proportional integral (PI) control on a control input to a controlled object on a basis of a difference between a target value set to the controlled object and an output from the controlled object, the controller comprising:

a processor coupled to a memory storing instructions for the processor to function as:

a model converting part that converts an ultra-local model obtained by modeling the controlled object into a state space model by defining a differential of an output of the controlled object including measurement noise by the control input and a deviation amount with respect to a reference model;

an estimation part that estimates the deviation amount of the ultra-local model on a basis of a Kalman filter constructed from the state space model;

a calculation part that obtains the control input on a basis of the estimated deviation amount, a proportional gain, and an integral gain,

wherein the output is an actual yaw rate of a vehicle, the target value is a target yaw rate of the vehicle, and the control input is a steering angle of the vehicle; and

a data acquisition part that acquires the target yaw rate set by the controller of the vehicle and the actual yaw rate detected by a sensor mounted on the vehicle during traveling of the vehicle,

wherein the processor outputs the steering angle obtained by the calculation part to a steering apparatus of the vehicle, and

wherein the model converting part converts the ultra-local model into the state space model by setting a differential of the deviation amount of the ultra-local model to 0.

2 . The controller according to claim 1 , wherein

the model converting part converts the ultra-local model into the state space model including a state equation and an observation equation defined by the output and the deviation amount.

3 . The controller according to claim 1 , wherein

the estimation part further estimates an output value of the output on the basis of the Kalman filter, and

the calculation part obtains the control input on the basis of the estimated deviation amount and output value, the proportional gain, and the integral gain.

4 . A control method which is a control method for performing proportional integral (PI) control on a control input to a controlled object on a basis of a difference between a target value set to the controlled object and an output from the controlled object; the control method comprising:

converting an ultra-local model obtained by modeling the controlled object into a state space model by defining a differential of an output of the controlled object including measurement noise by the control input and a deviation amount with respect to a reference model;

estimating the deviation amount of the ultra-local model on a basis of a Kalman filter constructed from the state space model;

obtaining the control input on a basis of the estimated deviation amount, a proportional gain, and an integral gain,

wherein the output is an actual yaw rate of a vehicle, the target value is a target yaw rate of the vehicle, and the control input is a steering angle of the vehicle;

acquiring the target yaw rate set by a controller of the vehicle and the actual yaw rate detected by a sensor mounted on the vehicle during traveling of the vehicle; and

outputting, by the controller, the steering angle obtained by the obtaining of the control input to a steering apparatus of the vehicle,

wherein the converting of the ultra-local model includes converting the ultra-local model into the state space model by setting a differential of the deviation amount of the ultra-local model to 0.