Turning control device, steering device, and vehicle

A steer-by-wire steering device comprising:

• a steering wheel configured to be operated by a driver;
• a steering shaft coupled to the steering wheel;
• a reaction force actuator configured to apply a steering reaction force to the steering shaft;
• a turning actuator configured to turn a steered wheel of a vehicle by a motor;
• and
• a control device configured to control the reaction force actuator and the turning actuator, wherein:
• the control device includes:
• a target steering angle setting circuit configured to set a target steering angle that is a target value of a steering angle of the steered wheel based on vehicle information;
• a target steering angle acquisition circuit configured to acquire the target steering angle from the target steering angle setting circuit on a predetermined acquisition cycle;
• a differential value calculation circuit configured to, when the target steering angle acquisition circuit has newly acquired the target steering angle, calculate a differential value that is a difference between the target value of the steering angle before the acquisition and the newly acquired target steering angle;
• a short-term target steering angle calculation circuit configured to calculate, by distributing the differential value, a short-term target steering angle that is a target value of the steering angle for each control cycle shorter than the acquisition cycle;
• and
• a motor control circuit configured to control the motor such that an actual steering angle becomes closer to the short-term target steering angle in each of the control cycles;
• and
• the short-term target steering angle calculation circuit is configured to calculate the short-term target steering angle based on a multiplied value obtained by multiplying the differential value by a coefficient according to the number of times of the control cycle since the target steering angle acquisition circuit has newly acquired the target steering angle, and on the target value of the steering angle before the acquisition.

A vehicle comprising:

• a turning actuator configured to turn a steered wheel of the vehicle by a motor;
• a target steering angle setting circuit configured to set a target steering angle that is a target value of a steering angle based on vehicle information;
• a target steering angle acquisition circuit configured to acquire the target steering angle from the target steering angle setting circuit on a predetermined acquisition cycle;
• a differential value calculation circuit configured to, when the target steering angle acquisition circuit has newly acquired the target steering angle, calculate a differential value that is a difference between the target value of the steering angle before the acquisition and the newly acquired target steering angle;
• a short-term target steering angle calculation circuit configured to calculate, by distributing the differential value, a short-term target steering angle that is a target value of the steering angle for each control cycle shorter than the acquisition cycle;
• and
• a motor control circuit configured to control the motor such that an actual steering angle becomes closer to the short-term target steering angle in each of the control cycles, wherein
• the short-term target steering angle calculation circuit is configured to calculate the short-term target steering angle based on a multiplied value obtained by multiplying the differential value by a coefficient according to the number of times of the control cycle since the target steering angle acquisition circuit has newly acquired the target steering angle, and on the target value of the steering angle before the acquisition.