Steering system

Abstract

The present invention relates to a steering system that well controls a reaction force. This steering system is an electric power steering system provided with a reaction force device and a steering device. In this steering system, a reaction force is controlled on the basis of a steering angle deviation, which is the difference between a target steering angle and an actual steering angle. In addition, the steering angle deviation is a phase-adjusted value. As a result, it is possible to suppress a delay in the influence of a change in the steering angle deviation on the reaction force, and to enable a driver to well know the steering state of the wheels by means of the reaction force applied to the steering operation member. And the reaction force can be well controlled.

Description

Technical Field

[0001] This invention relates to a steering system installed in a vehicle. Background Technology

[0002] Patent Document 1 describes an electric steering system comprising a reaction force device and a steering device. In the reaction force device of this steering system, the reaction force motor is controlled to achieve a target value for the reaction force torque, i.e., the operating torque. Furthermore, the operating torque is obtained based on the difference between the target steering angle and the actual steering angle, i.e., the steering angle deviation, and the target value of the operating torque is determined by performing phase advance processing on the obtained operating torque.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2023-048612 Summary of the Invention

[0004] The objective of this invention is to effectively control reaction forces.

[0005] This steering system is an electric steering system equipped with a reaction force device and a steering mechanism. In this system, the reaction force is controlled based on the steering angle deviation after phase adjustment, i.e., the phase adjustment completion deviation. As a result, the delay in the effect of changes in steering angle deviation on the reaction force can be suppressed, and the driver can clearly perceive the steering state of the wheels through the reaction force applied to the steering operation components. Excellent control of the reaction force is achieved.

[0006] As described above, in the steering system of Patent Document 1, the operating torque is obtained based on the steering angle deviation, and the target value of the operating torque is determined by performing phase advance compensation on the obtained operating torque. In contrast, in the steering system of the present invention, the target value of the reaction force is determined based on the phase adjustment deviation. Thus, in the steering system of the present invention, the target value of the reaction force is determined based on the steering angle deviation after phase adjustment, so compared with the steering system described in Patent Document 1, changes in the steering angle deviation can be quickly reflected in the target value of the reaction force, and the delay in the change of the target value of the reaction force relative to changes in the steering angle deviation can be effectively suppressed. Attached Figure Description

[0007] Figure 1 This is a diagram that conceptually represents a steering system according to one embodiment of the present invention.

[0008] Figure 2 This is a conceptual representation of the main parts of the aforementioned steering system, namely the steering angle control unit and its surroundings.

[0009] Figure 3This is a conceptual representation of a part of the aforementioned steering system, namely the reaction force control unit and its surroundings.

[0010] Figure 4 This is a diagram that conceptually represents the steering-side drive circuit of the aforementioned steering system.

[0011] Explanation of reference numerals in the attached drawings: 10: reaction force device; 12: steering device; 28: operating angle sensor; 30: reaction force actuator; 38: steering angle sensor; 40: reaction force control unit; 42: steering angle control unit; 74: vehicle speed sensor. Detailed Implementation

[0012] Hereinafter, an embodiment of the present invention, namely a steering system, will be described with reference to the accompanying drawings.

[0013] This steering system includes a reaction force device 10 and a steering mechanism 12. The reaction force device 10 and the steering mechanism 12 are mechanically independent of each other; in other words, they are mechanically disconnected components. This steering system is an electric steering system.

[0014] The reaction force device 10 includes a steering operation component 20, a reaction force transmission mechanism 22, and a reaction force actuator 26. The reaction force device 10 transmits a reaction force to the driver via the steering operation component 20. The steering operation component 20 can be operated by the driver and can be a rotatable steering wheel or a joystick capable of linear or curved reciprocating movement. In this embodiment, a rotatable steering wheel is used as the steering operation component 20.

[0015] The steering wheel 20 is connected to an input shaft 24, and a reaction force transmission mechanism 22 is provided on the input shaft 24. The reaction force transmission mechanism 22 can be, for example, a mechanism with multiple gears. A reaction force actuator 26 is connected to the reaction force transmission mechanism 22. While the reaction force actuator 26 includes a reaction force motor, it may also include a reducer in addition to the reaction force motor. The output torque of the reaction force actuator 26, i.e., the reaction force torque, is transmitted to the input shaft 24 via multiple gears and then to the steering wheel 20. An operation angle sensor 28, serving as an operation amount sensor, is installed on the input shaft 24. The operation angle sensor 28 detects the operation amount of the steering control operation component, i.e., the operation amount relative to the neutral position. In this embodiment, it detects the rotation angle of the steering wheel 20 relative to the neutral position, i.e., the operation angle.

[0016] The steering mechanism 12 steers the left and right steering wheels. The left and right steering wheels can be, for example, the left and right front wheels FW1 and FW2. In this embodiment, the steering mechanism 12 is a rack and pinion type device, including a steering actuator 30, a steering force transmission mechanism 32, a steering output shaft (i.e., output shaft) 33, a pinion 34, and a rack 35. While the steering actuator 30 includes a steering motor, it may sometimes also include a reducer in addition to the steering motor. The rack 35 is provided to extend along the width direction of the vehicle as its axial direction. The pinion 34 engages with the rack 35.

[0017] The steering force transmission mechanism 32 transmits the driving force of the steering actuator 30 to the output shaft 33, and rotates the output shaft 33 according to the rotation of the steering actuator 30. The steering force transmission mechanism 32 can be, for example, a mechanism with various gears (e.g., planetary gear mechanisms). The driving force of the steering actuator 30 is transmitted to the steering wheels FW1 and FW2 via the steering force transmission mechanism 32, the output shaft 33, the pinion 34, and the rack 35. The rotation of the pinion 34 causes the rack 35 to shift along its axial direction, and the displacement of the rack 35 in the axial direction causes the steering wheels FW1 and FW2 to turn left and right. A steering angle sensor 38 is mounted on the output shaft 33. The steering angle sensor 38 detects the rotation angle of the output shaft 33 from its neutral position. Based on the rotation angle of the output shaft 33, the actual steering angle of the left and right steering wheels FW1 and FW2, i.e., the actual steering angle δm, can be obtained.

[0018] Furthermore, the steering angle sensor can be configured to detect the displacement of rack 35 relative to the neutral position. The neutral position is the position when the vehicle is moving forward.

[0019] Furthermore, in the steering force transmission mechanism 32, by appropriately changing the meshing configuration of various gears, the rotation transmitted from the steering actuator 30 can be appropriately reduced and transmitted to the steering output shaft 33. This allows for continuous change of the steering gear ratio when steering wheels FW1 and FW2 are turned. The steering gear ratio is the ratio of the steering wheel 20's operating angle to the steering wheel's transmission angle (steering angle / operating angle).

[0020] This steering system is equipped with a computer-based control unit 39. The control unit 39 includes a reaction force control unit 40, a steering angle control unit 42, etc. The reaction force control unit 40 and the steering angle control unit 42 are connected to each other via an L-CAN (Local Controller Area Network) 44, which serves as a communication mechanism, in a manner that enables them to communicate with each other.

[0021] The reaction force control unit 40 controls the reaction force actuator 26. The reaction force control unit 40 is connected to the reaction force actuator 26 via a drive circuit (sometimes called the operating side drive circuit) 52, and is also connected to an operating angle sensor 28, a current sensor 54, etc. The current sensor 54 is provided in the drive circuit 52 and detects the current flowing to the reaction force actuator 26. The reaction force actuator 26 is controlled so that the reaction torque (operating torque) corresponding to the reaction force applied to the steering wheel 20 is close to the target value of the operating torque. Hereinafter, the target value of the operating torque will be referred to as the target operating torque.

[0022] The steering angle control unit 42 controls the steering actuator 30. The steering angle control unit 42 is connected to the steering actuator 30 via a drive circuit, i.e., a steering drive circuit 62, and is also connected to a steering angle sensor 38, a current sensor 64, a vehicle speed sensor 74, etc. The current sensor 64 detects the current flowing into the steering actuator 30, i.e., the actual current. The vehicle speed sensor 74 detects the vehicle's speed. The steering actuator 30 is controlled so that the actual steering angle δm of the steering wheels FW1 and FW2 is close to the target value of the steering angle, i.e., the target steering angle δt. The target steering angle δt is the target steering angle under the steering control of the steering wheels FW1 and FW2, and can also be called the target steering angle δt for steering control. The target steering angle δt will be described later.

[0023] In addition, the operating angle and steering angle are set to "0" in the neutral position, with positive values ​​representing one of the rotation angles in the left and right directions and negative values ​​representing the other.

[0024] In this steering system, the steering states of steering wheels FW1 and FW2 are transmitted to the driver via steering wheel 20 as reaction forces. The steering states of steering wheels FW1 and FW2 are determined by the states of steering wheels FW1 and FW2, the state of steering device 12, etc. The states of steering wheels FW1 and FW2 include the state of the road surface they contact and the state of the road. For example, when the coefficient of friction of the road surface contacted by steering wheels FW1 and FW2 is low, and neither steering wheels FW1 nor FW2 encounters obstacles such as curbs, and the steering device 12 is functioning normally, the actual steering angle δm is considered to closely follow the target steering angle δt. Compared to the case with a high coefficient of friction, steering wheels FW1 and FW2 are easier to steer when the coefficient of friction is low. In this case, the deviation between the actual steering angle δm and the target steering angle δt, i.e., the steering control deviation Da, is considered to be small. Therefore, in order to inform the driver of the steering states of steering wheels FW1 and FW2, the necessity of applying a large reaction force is considered low. Hereinafter, the state in which the actual steering angle δm follows the target steering angle δt well is sometimes referred to as good following.

[0025] Conversely, for example, when the coefficient of friction of the road surface in contact with steering wheels FW1 and FW2 is high, it is considered that steering wheels FW1 and FW2 will have difficulty following the target steering angle δt. Furthermore, if at least one of steering wheels FW1 and FW2 encounters an obstacle such as a curb, or if the steering device 12 is in an abnormal state or the steering angle control is abnormal, it is also considered that steering wheels FW1 and FW2 will have difficulty following the target steering angle δt. In these situations, the following performance is poor, and the steering control deviation Da tends to increase. Therefore, it is preferable to apply a large reaction force to inform the driver of the steering state of steering wheels FW1 and FW2.

[0026] In existing steering systems, the steering angle detected by steering angle sensor 38 (i.e., the actual steering angle δm) is converted into a steering control angle, i.e., the steering control angle conversion value. The difference between the steering control angle detected by steering angle sensor 28 and the steering control angle conversion value is also obtained, i.e., the steering control side deviation. Furthermore, the target operating torque is obtained based on the steering control side deviation to control the reaction force actuator 26. Therefore, the steering states of steering wheels FW1 and FW2 can be effectively communicated to the driver. However, since the processing for calculating the steering control angle conversion value is complex, it is desirable to perform reaction force control without using the steering control angle conversion value.

[0027] In contrast, we consider using the deviation Da of steering control to obtain the target operating torque and then performing reaction force control. However, the reaction force is delayed relative to the driver's operation of the steering wheel 20, making it difficult to quickly transmit the steering state of the steering wheels FW1 and FW2 to the driver.

[0028] That is, in the steering control unit 42, the steering target angle δt is obtained based on the control operating angle θ obtained in the reaction force control unit 40, and the steering actuator 30 is controlled to turn the steering wheels FW1 and FW2. Therefore, it is common for the deviation between the steering target angle δt and the actual steering angle δm detected by the steering angle sensor 38 to cause an operating delay relative to the steering wheel 20. Thus, if the control of the reaction force actuator 26 based on the steering control deviation Da is delayed relative to the steering wheel 20, it is difficult to effectively (quickly) transmit the steering state of the steering wheels FW1 and FW2 to the driver.

[0029] Therefore, in this embodiment, the target operating torque is determined based on the steering angle deviation after phase adjustment, i.e., the phase adjustment completion deviation Ds, and the reaction force actuator 26 is then subjected to this method. As a result, delay can be suppressed, and the steering states of the steering wheels FW1 and FW2 can be quickly transmitted to the driver via the steering wheel 20. In this embodiment, the phase adjustment is referred to as an adjustment that primarily suppresses delay. For example, this could be called phase advance, phase advance compensation, or considering differential values. The situation where the phase adjustment completion deviation Ds is obtained and the target operating torque is determined to control the reaction force actuator 26 is called deviation compensation control. Furthermore, the situation where the phase adjustment completion deviation Ds is obtained and the target operating torque is obtained can also be called deviation compensation control.

[0030] The following is based on Figure 2-4 Explain the deviation compensation control.

[0031] like Figure 3 As shown, the reaction force control unit 40 inputs the operating angle θm detected by the operating angle sensor 28, and obtains the control operating angle θ based on the detected operating angle θm. For example, the output can be limited and set as the control operating angle θm for the operating angle θm detected by the operating angle sensor 28. The output limitation may consider, for example, suppressing sudden changes in the detected value θm, or removing outliers. The control operating angle θ is supplied to the steering control unit 42 via the L-CAN 44.

[0032] like Figure 2 As shown, the steering angle control unit 42 is input with the control operating angle θ, vehicle speed v, actual steering angle δm, etc. In the steering angle control unit 42, the target steering angle for steering angle control of steering wheels FW1 and FW2, i.e., the steering target steering angle δt, is obtained based on the control operating angle θ, vehicle speed v, etc., and the steering actuator 30 is controlled based on the steering target steering angle δt.

[0033] Furthermore, in the steering angle control unit 42, a phase-adjusted target steering angle δh is obtained by phase adjustment of the target steering angle δt, and a phase-adjusted actual steering angle δm is obtained by phase adjustment of the actual steering angle δm. Moreover, a steering angle deviation Ds is obtained based on the phase-adjusted target steering angle δh and the phase-adjusted actual steering angle δmh. The steering angle deviation Ds is an example of a phase-adjusted steering angle deviation, i.e., a phase-adjusted deviation. The phase-adjusted deviation Ds is supplied to the reaction force control unit 40.

[0034] In VG (Variable gear ratio) decision B1, the steering gear ratio is obtained based on the vehicle speed v, and the target steering angle is temporarily obtained based on the control operating angle θ and the steering gear ratio. This VG decision B1 is called process B1, and the target steering angle temporarily obtained in process B1 is called the first temporary target steering angle δ1.

[0035] The steering gear ratio is determined so that, for example, steering wheels FW1 and FW2 turn rapidly at low vehicle speeds v and slowly at high vehicle speeds v. For example, the steering gear ratio can be set to a larger value at low vehicle speeds v than at high vehicle speeds v. The steering gear ratio is set to suppress a sharp decrease in the steering angle that occurs with changes in vehicle speed v.

[0036] In LPF processing B2, a cutoff frequency is obtained based on at least one of vehicle speed v and control operating angle θ. LPF (Low Pass Filter) processing, determined by the cutoff frequency, is then performed on the first temporary target steering angle δ1. The value after LPF processing is called the second temporary target steering angle δ2. The cutoff frequency is obtained based on at least one of vehicle speed v and control operating angle θ. For example, the cutoff frequency is lower when vehicle speed v is high than when vehicle speed v is low, and the cutoff frequency is lower when the absolute value of the control operating angle θ is large than when the absolute value of the control operating angle θ is small.

[0037] In output compensation B3, an output limit is applied to the second temporary target steering angle δ2, and a third temporary target steering angle δ3 is obtained. For example, when the vehicle is stationary, if the absolute value of the control operating angle θ increases (during static steering), it may be difficult to achieve the target steering angle relative to that operating angle in the steering device 12. Therefore, when the vehicle is stationary and the absolute value of the operating angle is greater than the set value, the target steering angle is limited. For example, the absolute value of the target steering angle can be limited to a value corresponding to the set value of the operating angle, or the absolute value of the target steering angle can be limited to a value obtained by multiplying the target steering angle by a set ratio γ less than 1. Furthermore, when the vehicle is moving, there is little need to limit the target steering angle. Therefore, in output compensation B3, the target steering angle is adjusted in a way that the change in the target steering angle between when the vehicle is stationary and when it is moving is gradual.

[0038] In β control B4 (processing B4), the third temporary target steering angle δ3 is corrected based on the difference between the operating angle and the vehicle's direction of travel, and a fourth temporary target steering angle δ4 is obtained. For example, when performing cross-road braking, the operating angle is approximately 0, and even if the driver intends to travel in a straight line, the vehicle will turn towards the side with higher μ due to the difference in road surface μ between the left and right sides. Therefore, it is preferable to steer the steering wheels towards the side with lower μ. This situation is taken into account when correcting the third temporary target steering angle δ3. Furthermore, this also applies when the vehicle is in an oversteer state, even if the driver performs a reverse operation.

[0039] In offset processing B5, the abrupt change in the fourth temporary target steering angle δ4 is suppressed, and the fifth temporary target steering angle δ5 is obtained. For example, if the change in the fourth temporary target steering angle δ4 becomes larger, the fifth temporary target steering angle δ5 is determined to be the value before the abrupt change (the previous value), and then it is determined that the difference between this value and the previous value gradually decreases.

[0040] In the residual current reduction process B6, the fifth temporary target steering angle δ5 is subjected to residual current reduction processing to obtain the sixth temporary target steering angle δ6. For example, even when the driver stops operating the steering wheel 20 and removes their hands from the steering wheel 20, current flows to the steering actuator 30 if the steering control deviation Da is not 0. For example, when it is determined that the vehicle is in a stopped state and the driver has released their hands, the sixth temporary target steering angle δ6 is obtained by reducing the current to the steering actuator 30. For example, the sixth temporary target steering angle δ6, which is also the steering target steering angle δt, is obtained by correcting it to a value closer to the actual steering angle than the fifth temporary target steering angle δ5, and is output to the steering-side drive circuit 62.

[0041] like Figure 4 As shown, in the steering drive circuit 62, angle FB control C1 and current FB control C2 are executed. In angle FB control C1, a target steering torque is determined as the output of the steering actuator 30, such that the actual steering angle δm is close to the target steering angle δt, and output to the current FB control unit C2. In current FB control unit C2, a target current for the steering actuator 30 is determined in order to output the target steering torque, and the steering actuator 30 is controlled in such a way that the actual current is close to the target current. Furthermore, the actual steering angle δm of the steering wheels FW1 and FW2 is detected by the steering angle sensor 38 and supplied to the steering angle control unit 42.

[0042] In contrast, the steering angle control unit 42 performs phase adjustment on the target steering angle δt and the actual steering angle δm. Phase adjustment includes processing for advance phase and processing for delay phase. Phase adjustment is sometimes referred to as phase advance compensation. In this embodiment, delay suppression processing B8 and phase advance filtering processing B9 and B10 are performed.

[0043] Delay suppression processing B8 is a process that suppresses the delay of the target steering angle δt relative to the control operating angle θ. This delay is considered to be caused by the execution of processes B1-B6. Furthermore, a control quantity (represented by the steering angle) corresponding to the delay caused by the execution of processes B1-B6 is obtained, and the target steering angle δt is corrected based on this control quantity, etc. The corrected target steering angle δt is referred to as the corrected target steering angle δ8.

[0044] In the delay suppression process B8, for example, the delay amount of the target steering angle can be obtained based on two or more of the first temporary target steering angle δ1 to the sixth temporary target steering angle δ6 from the outputs of processes B1-B6, and the target steering angle δt for steering can be corrected based on the control quantity corresponding to the delay amount. Specifically, the corrected target steering angle δ8 can be obtained by obtaining the control quantity based on the difference between the first temporary target steering angle δ1 and the sixth temporary target steering angle δ6, and by performing calculations such as adding the control quantity to the target steering angle δt for steering.

[0045] Furthermore, in processes B1-B6, most of the delay is generated in LPF process B2. Therefore, the control quantity can be obtained based on the difference between the first temporary target steering angle δ1 and the second temporary target steering angle δ2, and the steering target steering angle δt can be corrected. Specifically, the corrected target steering angle δ8 can be obtained by adding the difference between the first temporary target steering angle δ1 and the second temporary target steering angle δ2 to the steering target steering angle δt.

[0046] Furthermore, before obtaining the target steering angle δt for steering, in addition to LPF processing B2, a delayed increase processing Bx is sometimes performed. In this case, the control quantity can be obtained based on the difference between the value after the aforementioned delayed increase processing B2 and Bx and the value before the aforementioned processing B2 and Bx.

[0047] The phase-adjusted target steering angle δh is obtained by performing phase advance filtering B9 on the corrected target steering angle δ8. Phase advance filtering B9 is a process to suppress communication delay. The steering device 12 and the reaction force device 10 are connected via L-CAN 44. The phase advance filter is designed based on the communication delay (delay angle) between them. The phase-adjusted target steering angle δh can be phase-matched with the control operating angle θ.

[0048] In this embodiment, the actual steering angle δm is also phase-adjusted. The actual steering angle δm is processed in phase advance filtering process B10 to obtain the phase-adjusted actual steering angle δmh. The phase advance filter in phase advance filtering process B10 is the same as in the above case, and is designed based on communication delay.

[0049] The above can be used to refer to the processing of B8, 9, and 10 as phase adjustment and phase advance compensation, or to refer to one or more of the processing of B8, 9, and 10 as phase adjustment and phase advance compensation.

[0050] Furthermore, the difference between the actual steering angle δmh after phase adjustment and the target steering angle δh after phase adjustment is set as the phase adjustment deviation Ds, which is the steering angle deviation. The phase adjustment deviation Ds is supplied to the reaction force device 10 via L-CAN44. In the deviation compensation target operating torque calculation unit E1 of the reaction force control unit 40, the target value of the reaction force torque, i.e., the target operating torque, is obtained based on the phase adjustment deviation Ds. The absolute value of the target operating torque is determined to be a value where the absolute value of the phase adjustment deviation Ds is large when it is large and small when it is small. Figure 3 As shown, the obtained target operating torque is output to the operating side drive circuit 52. The target operating torque can be referred to as the deviation compensation target operating torque.

[0051] Thus, in this embodiment, the target operating torque is determined based on the phase adjustment completion deviation Ds. Therefore, the delay in the change of the target operating torque relative to the steering angle deviation can be well suppressed, and the steering states of the steering wheels FW1 and FW2 can be effectively transmitted to the driver as reaction torque.

[0052] When the steering wheels FW1 and FW2 follow the target steering angle δt determined by the steering wheel 20, the driver can obtain a normal (light) steering feel. On the other hand, when the steering wheels FW1 and FW2 do not follow the target steering angle δt, the steering state of the steering wheels FW1 and FW2 can be quickly transmitted to the driver through the reaction force applied to the steering wheel 20.

[0053] Furthermore, in autonomous driving mode, the need to transmit steering status to the driver is low because there is no driver input to the steering wheel 20. Therefore, the necessity for deviation compensation control is considered low.

[0054] Furthermore, in the above embodiment, delay suppression processing B8 and phase advance filtering processing B9 are performed on the target steering angle δt for steering to obtain the phase-adjusted target steering angle δh, and phase advance filtering processing B10 is performed on the actual steering angle δm to obtain the phase-adjusted actual steering angle δmh, thus obtaining the phase-adjusted deviation Ds. However, it is not necessary to perform all of the above processing B8, B9, and B10; performing at least one of the processing B8, B9, and B10 is sufficient.

[0055] In addition, it is possible to obtain the difference between the target steering angle δt and the actual steering angle δm, which is the steering control deviation Da, and to obtain the phase adjustment completed by suppressing the delay of the steering control deviation Da.

[0056] Furthermore, deviation compensation control can be executed when the steering control deviation Da is greater than a predetermined threshold Dath. This allows for sufficient application of reaction force control based on the phase adjustment completion deviation Ds, even in cases of poor following performance.

[0057] Furthermore, the control device 39 can be configured as a device that integrates the reaction force control unit 40 and the steering angle control unit 42. In other words, reaction force control and steering angle control can be performed in the same control device. In this case, phase advance filtering processes B9 and 10 are not essential. By executing the delay suppression process B8, the delay of the target steering angle δt relative to the operation of the steering wheel 20 can be suppressed.

[0058] Furthermore, the construction of the reaction force device 10 and the steering device 12 is not limited. For example, in the reaction force device 10, the operating angle sensor 28 can be configured to detect the steering wheel operating angle based on the rotation angle of the reaction force actuator. Additionally, a torque sensor can be provided on the input shaft 24, and the operating angle can be detected based on the output value of the torque sensor. In the steering device 12, the rotation of the steering actuator can be converted into linear movement of the steering shaft via a belt, pulley, or ball screw. Similarly, the steering angle sensor 38 can be configured to detect the steering angle based on the rotation angle of the steering actuator.

[0059] Furthermore, the logic for determining the target steering angle δt is not limited.

[0060] Furthermore, the present invention can be implemented based on the knowledge of those skilled in the art and in various modified and improved forms.

[0061] (1) A steering system, which is an electric steering system installed in a vehicle, comprising: a steering device that steers the wheels of the vehicle; a reaction force device that applies a reaction force to a steering operation component operable by a driver; and a control device that controls the reaction force, wherein the control device controls the reaction force based on a phase adjustment completion deviation of the actual steering angle of the wheel, i.e., the deviation between the actual steering angle and a target value of the steering angle of the wheel, i.e., the target steering angle, and the phase adjustment thereof.

[0062] The phase adjustment completion deviation can be set as, for example, the deviation obtained by performing phase adjustment on at least one of the actual steering angle and the target steering angle, based on at least one of the actual steering angle and the target steering angle after the phase adjustment. Alternatively, the phase adjustment completion deviation can be set as a value obtained by performing phase adjustment on the deviation between the actual steering angle before phase adjustment and the target steering angle before phase adjustment.

[0063] (2) According to the steering system described in (1), the control device adjusts the phase of the target steering angle and matches the phase of the operation of the steering control component to obtain the phase adjustment completion deviation.

[0064] When the steering control component is a rotary component such as a steering wheel, the phase of the operation corresponds to the rotation angle, or operating angle, relative to the neutral position. When the steering control component is a component such as a joystick that moves back and forth in a roughly linear or curved manner, the phase corresponds to the displacement relative to the neutral position.

[0065] (3) According to the steering system of (1) or (2), the control device includes: a steering angle control unit that controls the steering device to control the steering angle of the wheel, and a reaction force control unit that controls the reaction force device to control the reaction force, wherein the steering angle control unit and the reaction force control unit are connected in a communicable manner via a connection unit, and the control device obtains the phase adjustment completion deviation based on the communication delay via the connection unit.

[0066] For example, a phase advance filter can be designed based on the phase angle of the communication delay of the connection.

[0067] (4) In any one of the steering systems in (1) to (3), the control device obtains a target steering angle, i.e., a target steering angle for steering, by performing at least one processing on the operation amount of the steering operation component, and obtains a phase-adjusted target steering angle for steering based on the delay generated in one or more of the at least one processing, and obtains the phase-adjusted deviation.

[0068] For example, in the steering control unit, a target steering angle can be obtained by performing at least one operation on the steering operation component. In the control device, phase adjustment can be performed based on the delay generated in one or more of the at least one process, and a target steering angle, i.e., the phase-adjusted target steering angle, can be obtained. The phase-adjusted deviation can be obtained based on the phase-adjusted target steering angle.

Claims

1. A steering system, an electric power steering system installed in a vehicle, comprising: Steering mechanism that turns the wheels of the aforementioned vehicle; A reaction force device that applies a reaction force to steering control components operable by the driver; and The control device controls the aforementioned reaction force. The aforementioned control device controls the reaction force based on the deviation between the actual steering angle of the wheel and the target value of the steering angle of the wheel, i.e., the target steering angle, and the phase adjustment completed by adjusting the phase.

2. The steering system according to claim 1, characterized in that, The aforementioned control device adjusts the phase of the target steering angle and matches the phase of the operation of the steering control component to obtain the phase adjustment completion deviation.

3. The steering system according to claim 1 or 2, characterized in that, The aforementioned control device includes: a steering angle control unit that controls the steering device to control the steering angle of the wheels, and a reaction force control unit that controls the reaction force device to control the reaction force. The aforementioned steering angle control unit and the aforementioned reaction force control unit are connected in a communicative manner via a connecting part. The aforementioned control device obtains the phase adjustment completion deviation based on the communication delay via the aforementioned connection portion, which has undergone phase advance processing.

4. The steering system according to claim 1 or 2, characterized in that, The control device obtains a target steering angle, i.e. a target steering angle for steering, by performing at least one processing on the operation amount of the steering operation component, and obtains a phase-adjusted target steering angle for steering based on the delay generated in one or more of the at least one processing, and obtains the phase-adjusted deviation.

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