Abstract: A control device includes a processor and a storage device storing a program for controlling an operation of the processor. The processor determines whether a vehicle is in a straight-ahead traveling state, based on a vehicle speed detected by a vehicle speed sensor, a steering wheel torque applied to a steering wheel, and a steering wheel angle as a rotation angle of an input shaft. The processor stores the steering wheel angle in the memory when determining that the vehicle is in the straight-ahead traveling state. The processor stores the steering wheel angle in the memory multiple times when determining that the vehicle is in the straight-ahead traveling state. The processor calculates a corrected steering angle amount from a weighted average of the steering wheel angles stored in the memory.

Abstract: A processor calculates a steering wheel torque which an input shaft receives, from a torsion bar torque applied to a torsion bar between the input shaft to which an operation by a driver is input and an output shaft to which a motor applies a drive force, and a rotation angle of the input shaft, compares a calculated steering wheel torque with a threshold value, and determines that a vehicle is in a hands-off state in which the input shaft receives no input based on the operation by the driver when determining that the calculated steering wheel torque changes from a state in which the steering wheel torque exceeds a threshold value to a state in which the steering wheel torque falls below the threshold value.

Abstract: A control device includes a reaction force controller to generate an input torque input to a control target and control a reaction force transmitted to a steering person and an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model. The assist controller includes a high-pass filter with a first cutoff frequency, a low-pass filter with a second cutoff frequency higher than the first cutoff frequency, and a disturbance compensation value calculator. When a transfer function of the low-pass filter is Q(s) and a transfer function of the high-pass filter is HPF(s), a transfer function of a control target is constrained by a transfer function of the nominal model in a frequency band in which a gain in a gain characteristic of Q(s)·HPF(s) is 1.

Abstract: A control device that controls a control target including at least a motor in a steering mechanism including an input shaft to which a steering wheel is connected, an output shaft connected to the input shaft via a torsion bar, and the motor connected to the output shaft. The control device includes a reaction force controller to generate an input torque input to the control target based on a torsion bar torque generated in the torsion bar and to control a reaction force transmitted from the steering wheel to the steering person, and an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model. The assist controller is configured or programmed such that a transfer function of the control target is constrained by a transfer function of the nominal model in a frequency band.

Abstract: A control device includes a reaction force controller to generate an input torque input to the control target and control a reaction force transmitted from a steering wheel to a steering person, an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model, and a state feedback circuit to feed back a state compensation value to the input torque based on the output of the control target. The assist controller is configured or programmed such that the transfer function of the control target is constrained by the transfer function of the nominal model in the frequency band where the gain in the gain characteristic of the complementary sensitivity function with respect to the modeling error between the control target and the nominal model is approximately 1.

Abstract: A motor control device includes a torque controller to operate based on a steering torque and to give an input to a control target that is a motor, and a model following controller to generate a first correction torque based on an output from the control target. A model following controller includes a high-pass filter to remove a low frequency component from a first correction torque, a friction compensation calculator that is coupled in parallel to the high-pass filter to apply friction compensation to the first correction torque to calculate an estimated value of a mechanical friction torque, and an adder to add the estimated value of the friction torque to the first correction torque from which the low frequency component is removed by the high-pass filter to generate a second correction torque and feed back the second correction torque to an input to the control target.

Abstract: A motor control device includes a torque controller to operate based on a steering torque and to provide an input to a control target that is a motor, and a model following controller to generate a correction torque based on an output from the control target and to correct the input to the control target with the correction torque. A model following controller includes a high-pass filter with a first cutoff frequency and a low-pass filter with a second cutoff frequency larger than the first cutoff frequency. The model following controller is configured or programmed so that a transfer function of a control target is constrained to a nominal model in a frequency band in which a gain in a gain characteristic of Q(s)·HPF(s) is 1 where Q(s) is a transfer function of the low-pass filter and HPF(s) is a transfer function of the high-pass filter.

Abstract: A motor control device includes a model following controller to generate a correction torque based on an output from a control target that is a motor, and correct an input to the control target with the correction torque. A model following controller includes a high-pass filter with a first cutoff frequency and a low-pass filter with a second cutoff frequency larger than the first cutoff frequency, and is configured or programmed so that a transfer function of a control target is constrained to a nominal model in a frequency band in which a gain in a gain characteristic of Q(s)·HPF(s) is 1 where Q(s) is a transfer function of the low-pass filter and HPF(s) is a transfer function of the high-pass filter.

Abstract: A processor calculates a steering wheel torque which an input shaft receives, from a torsion bar torque applied to a torsion bar between the input shaft to which an operation by a driver is input and an output shaft to which a motor applies a drive force, and a rotation angle of the input shaft, compares a calculated steering wheel torque with a threshold value, and determines that a vehicle is in a hands-off state in which the input shaft receives no input based on the operation by the driver when determining that the calculated steering wheel torque changes from a state in which the steering wheel torque exceeds a threshold value to a state in which the steering wheel torque falls below the threshold value.

Abstract: A control device includes a processor and a storage device storing a program for controlling an operation of the processor. The processor determines whether a vehicle is in a straight-ahead traveling state, based on a vehicle speed detected by a vehicle speed sensor, a steering wheel torque applied to a steering wheel, and a steering wheel angle as a rotation angle of an input shaft. The processor stores the steering wheel angle in the memory when determining that the vehicle is in the straight-ahead traveling state. The processor stores the steering wheel angle in the memory multiple times when determining that the vehicle is in the straight-ahead traveling state. The processor calculates a corrected steering angle amount from a weighted average of the steering wheel angles stored in the memory.