JP2018111425A - Steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering device allowing for more accurately detecting erroneous coupling of a clutch.SOLUTION: A control device 60 determines whether an absolute value of a current Ic is satisfactorily larger than "0" (step S3) during automatic operation control (YES in step S1) and when a command to a clutch 30 is a release command (YES in step S2). When the absolute value of the current Ic is satisfactorily larger than "0" (YES in step S3), the control device 60 counts up count amount Ne (step S4) and determines whether the count amount Ne is larger than a count amount threshold Ne0 (step S5). The control device 60 determines that the clutch 30 is erroneous coupling (an abnormal time)(step S6) when the count amount Ne is larger than the count amount threshold Ne0 (YES in step S5).SELECTED DRAWING: Figure 5

Description

  The present invention relates to a steering apparatus.

  Conventionally, a so-called steer-by-wire (SBW) type steering device in which a steering wheel and a steered wheel are mechanically separated is known. For example, the steering device of Patent Document 1 steers a clutch that interrupts a power transmission path between a steering wheel and a steered wheel, a reaction force motor that is a source of a steering reaction force applied to a steering shaft, and a steered wheel. A steering motor that is a source of the turning force to be generated.

  When the vehicle travels, the control device of the steering device releases the clutch and maintains the state in which the steering wheel and the steered wheels are mechanically separated. And a control apparatus performs SBW control which steers a steered wheel through a steering motor while producing | generating a steering reaction force through a reaction force motor. On the other hand, when an abnormality occurs in a part of the SBW-type steering device such as a reaction force motor, the control device mechanically connects the steering wheel and the steered wheel by connecting a clutch. When either one of the reaction force motor and the steering motor can be operated, the control device generates an EPS (a steering assist force corresponding to the steering torque) through the reaction force motor or the steering motor that can be operated. The electric power steering device) control is executed.

  By the way, when the control device performs the SBW control, the clutch may be erroneously engaged (misconnected) even though the clutch is released. In this case, the control device assumes that the clutch is disengaged and continues the SBW control. The clutch misengagement is a case where the clutch is misengaged or the clutch misengagement and disconnection occur continuously.

  Therefore, in Patent Document 1, during the execution of the SBW control, the operation direction of the steering wheel of the driver is calculated from the time change of the steering angle, and the change of the current value of the current supplied to the steering motor is changed. The driving direction of the rudder motor is calculated, and when the calculated operation direction and the driving direction are opposite directions, it is determined that the clutch is in a mis-coupled state.

JP 2007-203885 A

  If the clutch is misengaged during execution of the SBW control, the operation of the reaction motor and the operation of the steered motor interfere with each other due to the mechanical connection between the steering wheel and the steered wheel. . For example, as a result of the other motor being dragged by a motor having a large output torque among the reaction force motor and the steering motor, the steering wheel rotates while vibrating. Note that the motor being dragged means that the rotation direction of the other motor becomes the same rotation direction as that of the motor having a large output due to the rotation of the motor having a large output. For this reason, the operation direction may coincide with the drive direction. That is, there is a situation in which the clutch disclosed in Patent Document 1 cannot accurately detect a clutch misengagement.

  An object of the present invention is to provide a steering device that can detect a clutch misengagement more accurately.

  A steering device that can achieve the above object is a steering device that executes at least one of automatic driving control and manual steering control, and has a steering shaft composed of a first shaft and a second shaft separated from each other, and the driver rotates. By transmitting the rotation of the steerable steering unit to the turning shaft of the vehicle via the steering shaft, the steering mechanism for turning the steered wheels, and the first shaft and the second shaft are mechanically connected. A clutch for connecting / disconnecting, a steering side motor for applying a steering reaction force or an assisting force to the steering unit, a turning side motor for giving a turning force for turning the steered wheels to the turning shaft, and the steering side And a control unit that controls driving of the motor and the steered side motor. When the clutch is disengaged, the control unit detects an error in the clutch based on a steering torque applied to the steering unit and a steering-side current supplied to the steering-side motor in accordance with a driver's rotation operation. It is determined whether or not it is a combination.

  According to this configuration, the erroneous coupling of the clutch can be determined based on the steering torque applied to the steering unit and the steering-side current supplied to the steering-side motor. When the clutch is in an open state during automatic driving control, the steering torque and the steering-side current are not generated under normal conditions because there is no driver's steering operation. On the other hand, when the first shaft and the second shaft are miscoupled at the time of an abnormal coupling of the clutch, a steering-side current may be generated by driving the reaction force actuator. Further, during manual steering control, when the clutch is disengaged, the steering torque should cancel the reaction force generated by the steering side current. However, when the clutch is misengaged, the steering torque and the reaction force corresponding to the steering-side current cannot be canceled sufficiently. The control unit can determine the clutch misengagement based on these differences.

In the above steering apparatus, it is preferable that a torque sensor for detecting the steering torque is provided between the steering unit and the steering side motor.
According to this configuration, by providing the torque sensor between the steering unit and the steering-side motor, it is possible to detect the erroneous clutch coupling more reliably. This is because even when a clutch misengagement occurs, the clutch misengagement can be determined only by the steering-side current if automatic driving control is being performed.

  In the above steering apparatus, the control unit performs automatic driving control, and the control unit performs automatic driving control. When the clutch is in an open state during automatic driving control, the steering-side current is When it is larger than the current threshold, it is preferable to determine that the clutch is misconnected.

  According to this configuration, during the automatic operation control, when the clutch is disengaged, the steering-side current should be equal to or less than the steering-side current threshold (almost “0”). This is because there is no need to generate a reaction force because there is no steering operation by the driver. For this reason, the control unit determines that the clutch is erroneously coupled when the steering side current is larger than the steering side current threshold even though the clutch is disengaged during the automatic driving control. Can do.

  In the steering apparatus, the control unit performs manual steering control, and the control unit is configured to perform the steering torque and the steering side when the clutch is in an open state during the manual steering control. When the sum with the current is not less than the determination threshold, it is preferable to determine that the clutch is erroneously coupled.

  According to this configuration, during manual steering control, the steering torque and the steering-side current should cancel each other when the clutch is in the released state. For this reason, the sum of the steering torque and the steering-side current should be less than the determination threshold. However, when the clutch is erroneously coupled, the steering torque and the steering-side current cannot cancel each other due to the influence of the steering-side motor or the like. For this reason, the control unit can determine the erroneous coupling of the clutch based on whether or not the sum of the steering torque and the steering-side current is less than the determination threshold value.

In the above steering apparatus, it is preferable that the control unit determines that the clutch is erroneously connected when the state determined that the clutch is erroneously connected continues for a predetermined time.
According to this configuration, even if it is instantaneously erroneously determined that the clutch is erroneously engaged, it is not immediately determined that the clutch is erroneously engaged. When a situation that is considered to be a clutch misengagement continues for a certain period of time, it is determined that the clutch is misengaged, so that a more reliable determination result is obtained.

  According to the steering apparatus of the present invention, it is possible to detect the clutch misengagement more accurately.

The block diagram which shows schematic structure of the steering apparatus of 1st Embodiment. The block diagram which shows the process which the control apparatus of the steering device of 1st Embodiment performs. The figure which shows the relationship of the various information at the time of automatic operation control in the steering apparatus of 1st Embodiment. The figure which shows the relationship of the various information at the time of manual steering control in the steering apparatus of 1st Embodiment. 6 is a flowchart illustrating a clutch misengagement determination method in the steering device according to the first embodiment. 9 is a flowchart illustrating a clutch misengagement determination method in the steering device of the second embodiment. The flowchart which shows the clutch misengagement determination method in the steering device of 3rd Embodiment. The figure which shows the relationship of the various information at the time of automatic driving | operation control in the steering apparatus of other embodiment.

<First Embodiment>
Hereinafter, a first embodiment of the steering device will be described.
As shown in FIG. 1, the steering device 1 is a steer-by-wire system in which a steering wheel 10 as a steering unit and a steered wheel 15 are mechanically separated via a clutch 30. The steering device 1 includes a steering mechanism 2 that steers the steered wheels 15 based on the operation of the steering wheel 10. Further, the steering device 1 is provided with a reaction force actuator 20 that applies a reaction force that is a force that resists the operation of the steering wheel 10, and a turning actuator 40 that applies a turning force for turning the steered wheels 15. It has been.

  The steering mechanism 2 includes a steering shaft 11 that is fixed to the steering wheel 10. The pinion teeth 11 a provided at the lower end portion of the steering shaft 11 mesh with the first rack teeth 12 a formed on the rack shaft 12. The rotational movement of the steering shaft 11 is converted into a reciprocating movement in the axial direction of the rack shaft 12 through the meshing of the pinion teeth 11a and the first rack teeth 12a. The reciprocating linear motion is transmitted to the left and right steered wheels 15 via the tie rods 14 respectively connected to both ends of the rack shaft 12, thereby changing the steered angles of the steered wheels 15.

  The reaction force actuator 20 is provided in the middle of the steering shaft 11. The reaction force actuator 20 includes a reaction force motor 21 that is a reaction force generation source, a reaction force side speed reducer 22 to which a rotating shaft 21 a of the reaction force motor 21 is coupled, and an inverter 23 that drives the reaction force motor 21. . The reaction force motor 21 is provided as a steering side motor.

  The steered actuator 40 includes a steered motor 41, a steered speed reducer 42, an inverter 44, and a pinion shaft 45. Pinion teeth 45 a formed on the pinion shaft 45 mesh with the second rack teeth 12 b of the rack shaft 12. The rotating shaft 41 a of the steered side motor 41 is connected to the pinion shaft 45 via the steered side reducer 42. An inverter 44 is connected to the steered side motor 41. The rack shaft 12 is accommodated in the rack housing 46.

  The steering shaft 11 is mechanically separated by a clutch 30 into a first shaft 16 on the steering wheel 10 side and a second shaft 17 on the steered wheel 15 side. By opening and closing the clutch 30, the first shaft 16 and the second shaft 17 are mechanically connected or disconnected.

  A spiral cable device 50 is coupled to the steering wheel 10. The spiral cable device 50 includes a first housing 51, a second housing 52, a tubular member 53, and a spiral cable 54. The first housing 51 is fixed to the steering wheel 10. The second housing 52 is fixed to the vehicle body. The tubular member 53 is accommodated in a space formed by the first housing 51 and the second housing 52 and is fixed to the second housing 52. The spiral cable 54 is wound around the cylindrical member 53. The spiral cable 54 is an electrical wiring that connects an electrical device such as a horn 55 fixed to the steering wheel 10 and a battery 56 fixed to the vehicle body.

  The control device 60 causes the reaction force control to generate a steering reaction force according to the operation of the steering wheel 10 through the reaction force motor 21, and turns the steered wheels 15 according to the operation of the steering wheel 10 through the turning side motor 41. Execute steering control. The control device 60 normally executes reaction force control and steering control with the clutch 30 disconnected.

  At this time, the control device 60 detects the rotation angle θs0 of the rotating shaft 21a of the reaction force motor 21 detected by the steering side sensor 70, the steering torque Trqs applied to the steering shaft 11 detected by the torque sensor 71, and the turning side sensor 72. The rotation angle θt0 of the rotating shaft 41a of the steered side motor 41 detected by the vehicle speed V and the vehicle speed V detected by the vehicle speed sensor 73 are captured. The torque sensor 71 is provided between the steering wheel 10 and the reaction force motor 21 (a portion of the steering shaft 11 to which the reaction force motor 21 is connected via the steering-side speed reducer 22). Further, the control device 60 controls the steering angle θa detected by the steering angle sensor 74, the current Ic flowing through the reaction force motor 21 detected by the steering side current sensor 75, and the steering detected by the steering side current sensor 76. The current It flowing through the side motor 41 is captured.

  The control device 60 includes a CPU 61 (central processing unit) and a memory 62. The CPU 61 of the control device 60 controls the reaction force motor 21 and the steered side motor 41 by executing a program stored in the memory 62.

Next, a part of the processing executed by the control device 60 is shown.
As shown in FIG. 2, the integration processing unit M2 sets the rotation angle θs0 detected by the steered side sensor 72 and the rotation angle θt0 detected by the steered side sensor 72 to an angle region wider than 0 to 360 degrees. The rotation angles θs and θt are obtained by converting into the numerical values.

  The conversion unit M4 calculates the turning angle θp by multiplying the rotation angle θs calculated by the integration processing unit M2 by the conversion coefficient Ks. Here, the conversion coefficient Ks is determined according to the rotational speed ratio between the reaction force side reduction gear 22 and the rotation shaft 21 a of the reaction force motor 21. For this reason, the steering angle θh is a rotation angle of the steering wheel 10 with respect to the neutral position. The conversion coefficient Kt is determined according to the product of the rotational speed ratio between the steered side reduction gear 42 and the rotational shaft 41a of the steered side motor 41 and the rotational speed ratio between the second shaft 17 and the pinion shaft 45. .

  It is assumed that the rotation angles θs, θt, the steering angle θh, and the turning angle θp are positive when the rotation angle is in a predetermined direction, and negative when the rotation angle is in the opposite direction. In addition, here, the fact that the rotation angles θs, θt, the steering angle θh, and the turning angle θp are large means that the amount of change from the neutral position is large. That is, when the rotation angles θs, θt, the steering angle θh, and the turning angle θp are large, the absolute value of a parameter that can take a positive or negative value is large.

  The assist torque setting processing unit M6 sets the assist torque Trqa * based on the steering torque Trqs. The assist torque Trqa * is set to a larger value as the steering torque Trqs is larger. The addition processing unit M8 outputs a value obtained by adding the steering torque Trqs to the assist torque Trqa *.

  The reaction force setting processing unit M10 sets a reaction force Fir that is a force that resists rotation of the steering wheel 10. Specifically, based on the turning angle θp, the reaction force setting processing unit M10 sets the reaction force Fir to a larger value when the turning angle θp is large than when the turning angle θp is small.

The deviation calculation processing unit M12 outputs a value obtained by subtracting the reaction force Fir from the output of the addition processing unit M8.
The steering angle command value calculation processing unit M20 sets the steering angle command value θh * based on the output value of the deviation calculation processing unit M12. Here, a model formula expressed by the following formula (1) that relates the output value Δ of the deviation calculation processing unit M12 and the steering angle command value θh * is used.

Δ = C · θh * '+ J · θh *''(1)
The model expressed by the above formula (1) is a model that defines the relationship between the axial force of the rack shaft 12 and the steering angle θh when the steering wheel 10 and the steered wheel 15 are mechanically coupled. . In the above equation (1), the viscosity coefficient C is a model of the friction of the steering device 1 and the inertia coefficient J is a model of the inertia of the steering device 1. Here, the viscosity coefficient C and the inertia coefficient J are variably set according to the vehicle speed V.

  The steering angle feedback control unit M22 calculates the feedback torque Trqr1 * by executing feedback control based on the deviation between the steering angle command value θh * and the steering angle θh. Specifically, the steering angle feedback control unit M22 feeds back the sum of the proportional element, the integral element, and the differential element, which is an operation amount that changes based on the deviation between the steering angle command value θh * and the steering angle θh. Calculated as torque Trqr1 *.

  The addition processing unit M24 adds the sum of the feedback torque Trqr1 * calculated by the steering angle feedback control unit M22 and the assist torque Trqa * calculated by the assist torque setting processing unit M6 to the reaction force command value for the reaction force motor 21. Calculated as Trqr * (torque command value).

  The operation signal generation processing unit M26 calculates the operation signal MSs of the inverter 23 based on the reaction force command value Trqr *. The operation signal generation processing unit M26 calculates a current command value for the dq axis by executing current feedback control based on the reaction force command value Trqr *.

  The steering angle ratio variable processing unit M28 sets a target operating angle θv * for variably setting the steering angle ratio, which is the ratio of the steering angle θh and the turning angle θp, based on the steering angle command value θh * and the vehicle speed V. To do. The addition processing unit M30 calculates the turning angle command value θp1 * by adding the target operating angle θv * to the steering angle command value θh *.

  The differential steering processing unit M32 calculates the steering correction amount θd by multiplying the change speed of the steering angle command value θh * by the gain Kd. The addition processing unit M34 calculates the turning angle command value θp * by adding the steering correction amount θd to the turning angle command value θp1 *.

  The automatic driving processing unit M100 calculates a command value for automatic driving processing for turning the steered wheels 15 separately from the driver's operation of the steering wheel 10. Specifically, the automatic operation processing unit M100 calculates an automatic operation command angle θ * that is a command value of a turning angle when performing automatic operation based on various detection values. In addition, although the automatic driving | operation process part M100 is a process performed with the automatic driving | operation control apparatus 100, it has illustrated in FIG. 2 for convenience.

  An example of a method for calculating the automatic operation command angle θ * by the automatic operation processing unit M100 will be described. First, information on a white line that divides a lane is acquired by a camera or the like, and a target locus for vehicle travel is set based on the information on the white line. Then, based on the target locus, an open-loop operation amount of the turning angle for setting the vehicle locus as the target locus is set as the target turning angle. The automatic driving processing unit M100 calculates the automatic driving command angle θ * as a feedback operation amount for feedback control of the actual turning angle to the target turning angle. This target turning angle is determined from the amount of open loop operation, the yaw rate of the vehicle, the yaw angle, the amount of vehicle deviation from the center of the lane, and the like.

  The switching processing unit M35 selects and outputs either the turning angle command value θp * calculated by the addition processing unit M34 or the automatic driving command angle θ * calculated by the automatic driving processing unit M100. The switching processing unit M35 selects the automatic operation command angle θ * when the automatic operation control is being executed, and selects the turning angle command value θp * when the manual steering control is being executed. The automatic driving control is to control the behavior of the vehicle based on the target locus of the vehicle obtained by a camera or the like without the driver's steering operation (the steering operation may be taken into account). The vehicle behavior is controlled based on the steering operation of the driver. As an example, switching between automatic driving control and manual steering control is determined based on whether or not the steering torque Trqs is equal to or greater than a threshold value.

  The turning angle feedback control unit M36 executes a feedback control based on a deviation between the turning angle command value θp * and the turning angle θp, thereby providing a turning angle torque command as a torque command value for the turning side motor 41. The value Trqt * is calculated. Specifically, the turning angle feedback control unit M36 steers the sum of proportional elements, integral elements, and differential elements output based on the deviation between the turning angle command value θp * and the turning angle θp. Calculated as the angular torque command value Trqt *.

The operation signal generation processing unit M38 calculates the operation signal MSt of the inverter 44 based on the turning angle torque command value Trqt * calculated by the turning angle feedback control unit M36.
According to the above processing, the steered wheels 15 are moved according to the driver's operation of the steering wheel 10 in the released state of the clutch 30, that is, in the state where the power transmission path between the steering wheel 10 and the steered wheels 15 is interrupted. Can be steered.

  Further, when the automatic operation command angle θ * is selected by the switching processing unit M35, the turning angle feedback control unit M36 executes feedback control based on the deviation between the automatic operation command angle θ * and the turning angle θp. Thus, the turning angular torque command value Trqt * is calculated. Thereby, when the automatic operation control is being executed in the released state of the clutch 30, the steered wheels 15 can be steered based on the target locus.

  Further, the target operating angle θv * calculated by the steering angle ratio variable processing unit M28 (gear ratio variable unit) is such that the steering angle θh is the steering angle at high vehicle speeds (for example, when the vehicle speed V is greater than the threshold value). It is set to change more greatly than θp. Further, the target operating angle θv * is set so that the turning angle θp changes more greatly than the steering angle θh when the vehicle speed is low (for example, when the vehicle speed V is smaller than the threshold value). When the vehicle speed V is equal to the threshold value), the steering angle θh and the turning angle θp are set to change in the same way.

  The control device 60 switches from automatic steering control to manual steering control when the magnitude of the steering torque Trqs exceeds a predetermined value during automatic driving control. Further, the control device 60 outputs a coupling command or a release command to the clutch 30 based on various information. When a release command is output to the clutch 30, the clutch 30 is normally in a non-coupled state (open state). On the other hand, when the coupling command is output, the clutch 30 is normally in a coupled state. The control device 60 determines whether the command output to the clutch 30 is a release command.

Next, during automatic operation control, the relationship between various types of information when the clutch 30 is in a normal state when the clutch 30 is in an open state and when the clutch 30 is in an abnormal state where the clutch 30 is in an erroneously connected state will be described.
As shown in FIG. 3, when the vehicle is normal and at a high vehicle speed, the steering angle θa is larger than the rotation angle θt, and the rotation angle θs is larger than the rotation angle θt. The steering angle θa is equal to the rotation angle θs. This is because the steering angle θh is set so as to change more greatly than the steering angle θp by the steering angle ratio variable processing unit M28. Further, the steering torque Trqs is in the vicinity of “0” because it is considered that there is no steering operation by the driver because the automatic driving control is being performed. Further, since the driver does not perform the steering operation, the current Ic does not need to generate assist torque as manual steering control, and is around “0”.

  When the vehicle speed is normal and the vehicle speed is medium, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. The steering angle ratio variable processing unit M28 sets the steering angle θh to change in the same manner as the turning angle θp. Further, the steering torque Trqs and the current Ic are in the vicinity of “0” as in the case of the high vehicle speed.

  In normal times and at low vehicle speeds, the steering angle θa is smaller than the rotation angle θt, and the rotation angle θs is smaller than the rotation angle θt. The steering angle θa is equal to the rotation angle θs. This is because the steering angle θh is set so as to change more greatly than the steering angle θp by the steering angle ratio variable processing unit M28. Further, the steering torque Trqs and the current Ic are in the vicinity of “0” as in the case of the high vehicle speed.

  On the other hand, there is a concern that the clutch 30 may be erroneously coupled due to an abnormality occurring in a part of the steering device 1 even though the clutch 30 is maintained in the released state.

  When the vehicle speed is abnormal and the vehicle speed is high, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. This is because the first shaft 16 and the second shaft 17 rotate integrally when the clutch 30 is miscoupled, so that the change in the steering angle θh and the change in the turning angle θp are one-to-one. It is because it corresponds to. Further, the steering torque Trqs is in the vicinity of “0” as in the normal state because the automatic operation control is being performed. On the other hand, unlike the normal case, the absolute value of the current Ic flowing through the reaction motor 21 is sufficiently larger than “0” (the absolute value of the current Ic is larger than the current threshold Ic0). That is, in the case of abnormality, the steering torque Trqs is almost “0”, but the current Ic is sufficiently large, in other words, the reaction force is generated by the reaction force motor 21. Even when the first shaft 16 and the second shaft 17 rotate together due to the erroneous coupling of the clutch 30, the reaction force motor 21 is driven to make the steering angle θh larger than the turning angle θp. It is because it is considered. Moreover, in this case, it is because another motor may be rotated by the motor with the larger torque among the reaction force motor 21 and the steered side motor 41.

  When the vehicle speed is abnormal and the vehicle speed is middle, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. Further, the steering torque Trqs is in the vicinity of “0” as in the normal case. On the other hand, unlike the normal case, the absolute value of the current Ic is sufficiently larger than “0”.

  When the vehicle is abnormal and the vehicle speed is low, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. Further, the steering torque Trqs is in the vicinity of “0” as in the normal case. In addition, the current Ic is sufficiently larger than “0” in its absolute value, unlike the normal case.

Next, the relationship between various information during normal steering control and during normal operation will be described.
As shown in FIG. 4, in the normal time and at the high vehicle speed, the steering angle θa is larger than the rotation angle θt, and the rotation angle θs is larger than the rotation angle θt. The steering angle θa is equal to the rotation angle θs. This is because the steering angle θh is set so as to change more greatly than the steering angle θp by the steering angle ratio variable processing unit M28. Next, it is considered that the steering torque Trqs is not in the vicinity of “0” unlike the case of the automatic driving control because the manual steering control is performed. Similarly, the current Ic is considered not to be near “0”. In this case, since the reaction force by the reaction force motor 21 is generated so as to cancel the steering torque Trqs generated by the steering operation of the driver, the reaction force Fc corresponding to the current Ic is balanced with the steering torque Trqs. For this reason, the sum of the steering torque Trqs and the reaction force Fc corresponding to the current Ic is “0”.

When the vehicle speed is normal and the vehicle speed is medium, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. Further, the sum of the steering torque Trqs and the reaction force Fc is “0”.
In normal times and at low vehicle speeds, the steering angle θa is smaller than the rotation angle θt, and the rotation angle θs is smaller than the rotation angle θt. The steering angle θa is equal to the rotation angle θs. Further, the sum of the steering torque Trqs and the reaction force Fc is “0”.

  On the other hand, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other at the time of abnormality and at a high vehicle speed. The absolute value of the sum of the steering torque Trqs and the reaction force Fc is greater than “0”. In this case, a current Ic, that is, a reaction force Fc is generated in the same direction as the steering torque Trqs.

When the vehicle speed is abnormal and the vehicle speed is middle, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. Further, the steering torque Trqs is equal to the negative reaction force Fc.
When the vehicle is abnormal and the vehicle speed is low, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. Further, the absolute value of the steering torque Trqs is smaller than the absolute value of the reaction force Fc. In this case, a current Ic, that is, a reaction force Fc is generated in a direction opposite to the steering torque Trqs.

  In this way, the control device 60 determines the erroneous coupling of the clutch 30 based on various information that changes depending on whether it is normal or abnormal, high vehicle speed, or low vehicle speed. In addition, when the torque exceeding the detection limit of the steering torque Trqs by the torque sensor 71 is input and the current Ic detected by the reaction force motor 21 approaches the detection limit, the control device 60 connects the clutch 30. EPS (electric power steering device) control for generating a steering assist force by the reaction force motor 21 or the steered side motor 41 is executed.

Next, an erroneous coupling determination method for the clutch 30 performed by the control device 60 will be described.
As shown in FIG. 5, the control device 60 determines whether or not automatic driving control is being performed (step S1). For example, when automatic driving control is performed when the automatic driving switch is pressed, or when there is no intervention operation to the automatic steering control by the driver because the steering torque Trqs is smaller than the threshold value, the automatic driving control is being performed. Determined.

When the automatic operation control is being performed (YES in step S1), control device 60 determines whether or not the command to clutch 30 is a release command (step S2).
When the command to clutch 30 is a release command (YES in step S2), control device 60 determines whether or not the absolute value of current Ic is sufficiently larger than “0” (step S3). As shown in FIG. 3, when the current Ic is in the vicinity of “0”, the clutch 30 is considered to be in the disengaged state, whereas when the current Ic is sufficiently larger than “0”, the miscoupled state It is thought that there is. For this reason, by determining whether or not the current Ic is sufficiently larger than “0”, it is possible to determine whether or not it is in a miscoupled state.

  When the absolute value of current Ic is sufficiently larger than “0” (YES in step S3), control device 60 increments count amount Ne (step S4), and count amount Ne is greater than count amount threshold value Ne0. Is determined (step S5). The count amount Ne is counted up ("+1") when there is a situation that is considered to be an erroneous coupling of the clutch 30, and is counted down ("-1") when there is a situation that is not considered to be an erroneous coupling. The

  Then, when the count amount Ne is larger than the count amount threshold value Ne0 (YES in step S5), the control device 60 determines that the clutch 30 is erroneously connected (during abnormality) (step S6). That is, when a situation that is considered to be an erroneous coupling of the clutch 30 continues for a certain time, the erroneous coupling of the clutch 30 is detected. As the count amount threshold value Ne0 is set larger, the determination result that the clutch 30 is erroneously coupled becomes more reliable.

  In contrast, when the count amount Ne is equal to or less than the count amount threshold value Ne0 (NO in step S5), the control device 60 determines that the clutch 30 is in the released state (normal state) (step S7).

Then, after determining that the clutch 30 is in the released state in step S7, the control device 60 repeats the determination in order from step S1 again.
When the command to clutch 30 is not the release command (NO in step S2), control device 60 counts down count amount Ne (step S8), and determines whether count amount Ne is greater than count amount threshold value Ne0. (Step S5). Even if erroneously coupled, the command to the clutch 30 is a coupled command, so that there is no erroneous recognition of the coupled state of the clutch 30 of the control device 60, so the countdown is performed. Note that the lower limit value of the count amount Ne is, for example, “0”.

  When determining that the absolute value of the current Ic is not sufficiently larger than “0” (NO in step S3), the control device 60 counts down the count amount Ne (step S8), and the count amount Ne is the count amount. It is determined whether or not it is larger than the threshold value Ne0.

  Next, when the automatic operation control is not being performed (NO in Step S1), the control device 60 determines whether or not the command to the clutch 30 is a release command (Step S9). The case where the automatic driving control is not being performed is a case where the steering torque Trqs is greater than or equal to a threshold value and the driver's intervention operation is assumed to be switched to manual steering control.

  When the command to clutch 30 is a release command (YES in step S9), control device 60 determines whether or not the sum of reaction force Fc corresponding to steering torque Trqs and current Ic is “0” (step S9). Step S10). The reaction force Fc is a torque that acts on the steering shaft 11 when the current Ic is supplied to the reaction force motor 21. Whether or not the sum of the reaction force Fc corresponding to the steering torque Trqs and the current Ic is “0”, in other words, whether or not the absolute value of the sum of the steering torque Trqs and the reaction force Fc is smaller than the threshold value β. is there. As shown in FIG. 4, when the sum of the steering torque Trqs and the reaction force Fc is “0”, the clutch 30 is considered to be in the disengaged state, whereas the sum of the steering torque Trqs and the reaction force Fc is When it is not “0”, it is considered to be in a misbonded state. Therefore, by determining whether or not the sum of the steering torque Trqs and the reaction force Fc is “0”, it is possible to determine whether or not there is an erroneous coupling state.

  When the sum of steering torque Trqs and reaction force Fc is “0” (YES in step S10), control device 60 increments count amount Ne (step S11), and count amount Ne is greater than count amount threshold value Ne0. It is determined whether it is larger (step S12).

  When the count amount Ne is larger than the count amount threshold value Ne0 (YES in step S12), the control device 60 determines that the clutch 30 is erroneously connected (during abnormality) (step S13).

  In contrast, when the count amount Ne is not greater than the count amount threshold value Ne0 (NO in step S12), the control device 60 determines that the clutch 30 is in the released state (normal time) (step S14).

Then, after determining that the clutch 30 is in the released state in step S14, the control device 60 repeats the determination in order from step S1 again.
When the command to clutch 30 is not a release command (NO in step S9), control device 60 counts down count amount Ne (step S15), and determines whether count amount Ne is greater than count amount threshold value Ne0. (Step S12).

  When the sum of the steering torque Trqs and the reaction force Fc is not “0” (NO in step S10), the control device 60 counts down the count amount Ne (step S15), and the count amount Ne is smaller than the count amount threshold value Ne0. It is determined whether it is larger (step S12).

The operation and effect of this embodiment will be described.
(1) As a comparative example, when the misengagement of the clutch 30 occurs when the misengagement of the clutch 30 is detected based on the operation direction of the steering wheel 10 and the drive direction of the steered side motor 41 during execution of the SBW control. Since the reaction force motor 21 and the steered side motor 41 interfere with each other, it is not possible to accurately detect the erroneous coupling of the clutch 30. Further, when either one of the operation direction and the driving direction cannot be accurately detected, it is impossible to accurately detect the erroneous coupling of the clutch 30.

  In this regard, in the present embodiment, the control device 60 detects the erroneous coupling of the clutch 30 based on the steering torque Trqs detected by the torque sensor 71 and the current Ic detected by the steering-side current sensor 75. For example, during the automatic operation control, when the clutch 30 is in the released state, the erroneous coupling of the clutch 30 can be detected when the current Ic is sufficiently larger than “0”. Since it is considered that the driver does not perform the steering operation during the automatic driving control, the reaction force motor 21 does not need to generate the reaction force Fc and the current Ic is “0” when the clutch 30 is in the released state. It is considered to be near. However, in this case, the current Ic flowing through the reaction force motor 21 is sufficiently larger than “0” means that the rotational force of the steered side motor 41 is transmitted to the steering side due to erroneous coupling of the clutch 30. It is thought that it has come. Therefore, the control device 60 can determine whether or not the clutch 30 is erroneously connected based on whether or not the current Ic is sufficiently larger than “0”.

  During manual steering control in which the driver performs steering operation, the clutch 30 is used when the command to the clutch 30 is a release command, or when the sum of the reaction force Fc corresponding to the steering torque Trqs and the current Ic is not “0”. Can be detected. In other words, it is considered that the steering torque Trqs accompanying the steering operation of the driver is balanced with the reaction force Fr (torque) generated in the reaction force motor 21 corresponding to the current Ic in the normal state. For this reason, in the normal state, the sum of the steering torque Trqs and the reaction force Fc should be “0”. However, when the clutch 30 is erroneously coupled, torque generated by driving the steered side motor 41 also acts on the steering shaft 11, so that the sum of the steering torque Trqs and the current Ic is not “0”. Therefore, the control device 60 can determine whether or not the clutch 30 is erroneously connected based on whether or not the sum of the steering torque Trqs and the reaction force Fc is “0”.

Thus, in the present embodiment, it is possible to detect the erroneous coupling of the clutch 30 more reliably based on the steering torque Trqs and the current Ic.
(2) When detecting erroneous coupling of the clutch 30 based on the steering angle θa, the rotational angle θs, and the rotational angle θt, that is, when detecting erroneous coupling of the clutch 30 based on the steering direction and the steering direction, The relationship between these angles changes accordingly. At this time, even at the middle vehicle speed, even if the clutch 30 is in the disengaged state, the rotation angle θs and the rotation angle θt coincide, in other words, the rotation amount of the reaction force motor 21 and the rotation amount of the steered side motor 41 are the same. Since they coincide with each other, it is not possible to determine erroneous coupling of the clutch 30. That is, at the medium vehicle speed, the control device 60 cannot determine the erroneous coupling of the clutch 30 based on whether or not the steering angle θa, the rotation angle θs, and the rotation angle θt match each other.

In this regard, according to the present embodiment, it is possible to more reliably detect the erroneous coupling of the clutch 30 based on the reaction force Fc corresponding to the steering torque Trqs and the current Ic even at the middle vehicle speed.
(3) In the misengagement determination process shown in FIG. 5, it is determined that the clutch 30 is in the misengaged state when a situation in which the clutch 30 is considered to be in the misengaged state continues for a certain period of time. For example, when current Ic is sufficiently larger than “0” or when the sum of steering torque Trqs and reaction force Fc is not “0”, control device 60 considers that clutch 30 is miscoupled. It is done. However, since it is also assumed that a situation that is considered to be a miscoupled state of the clutch 30 due to the influence of a systematic error or noise, it is assumed that when the situation that is considered to be a miscoupled state continues for a certain period of time, the clutch It is determined that there are 30 misbonds. Thereby, the erroneous coupling of the clutch 30 can be detected more reliably.

  (4) In the present embodiment, since the erroneous coupling of the clutch 30 is detected by the reaction force Fc (torque) generated by the reaction force motor 21 due to the current Ic, the steering torque Trqs, and the like, the clutch even when the steering shaft 11 is not rotating. Thirty misbonds can be detected. That is, in the control device 60, the clutch 30 is erroneously coupled, and the rotation amount of the reaction motor 21 and the rotation amount of the steered side motor 41 are balanced, and the steering angle θa, the rotation angle θs, and the rotation angle θt are Even if it does not change, the erroneous coupling of the clutch 30 can be detected based on the steering torque Trqs and the reaction force Fc.

  (5) Even if a sensor for detecting erroneous coupling of the clutch 30 is not newly provided, the erroneous coupling of the clutch 30 can be more reliably performed by using the torque sensor 71 and the steering-side current sensor 75 that are originally provided. Can be detected.

Second Embodiment
Hereinafter, a second embodiment of the steering apparatus will be described. Here, the difference from the first embodiment will be mainly described.

  Although the erroneous coupling determination process shown in FIG. 5 determines the erroneous coupling of the clutch 30, the erroneous coupling determination process shown in FIG. 6 may be executed in addition to this. After performing the erroneous coupling determination process using the current Ic in FIG. 5, the erroneous coupling determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt in FIG. 6 is performed. Further, when the current Ic can no longer be detected by the steering-side current sensor 75, a misconnection determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt may be executed. Hereinafter, the misconnection determination process shown in FIG. 6 will be briefly described.

First, the control device 60 determines whether or not the command to the clutch 30 is a release command (step S20).
When it is determined that the command to the clutch 30 is not a release command (NO in step S20), the control device 60 determines that the clutch 30 is in an open state (step S21), and all processing of this erroneous coupling determination process. Exit.

On the other hand, when it is determined that the command to the clutch 30 is a release command (YES in step S20), the control device 60 determines whether the vehicle speed is high (step S22).
When determining that the vehicle speed is high (YES in step S22), control device 60 determines whether or not steering angle θa and rotation angle θs are larger than rotation angle θt and steering angle θa and rotation angle θs are equal. (Step S23).

  When the steering angle θa and the rotation angle θs are larger than the rotation angle θt and the steering angle θa and the rotation angle θs are equal (YES in step S23), the control device 60 determines that the state is open (step S24). Further, if the steering angle θa and the rotation angle θs are not larger than the rotation angle θt, or if the steering angle θa and the rotation angle θs are not equal (NO in step S23), the control device 60 determines that the coupling is incorrect (NO in step S23). Step S25).

  When determining that the vehicle speed is not high (NO in step S22), the control device 60 determines whether the vehicle speed is low (step S26). When the vehicle speed is low (YES in step S26), the steering angle θa and the rotation angle are determined. It is determined whether θs is smaller than the rotation angle θt and whether the steering angle θa and the rotation angle θs are equal (step S27).

  When the steering angle θa and the rotation angle θs are smaller than the rotation angle θt and the steering angle θa and the rotation angle θs are equal (YES in step S27), the control device 60 determines that the state is open (step S28). Further, if the steering angle θa and the rotation angle θs are not smaller than the rotation angle θt, or if the steering angle θa and the rotation angle θs are not equal (NO in step S27), the control device 60 determines that the coupling is incorrect (NO in step S27). Step S29).

  Next, when determining that the vehicle speed is not low (NO in step S26), the control device 60 determines that the vehicle speed is medium (step S30), and determines that determination is impossible (step S31). That is, in the misengagement determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt, the misengagement of the clutch 30 cannot be detected at the middle vehicle speed. 30 misbonds are determined.

  This completes the erroneous coupling determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt. Note that step S22 and step S26 may be combined into one determination. In this case, for example, it is determined whether or not the vehicle speed is medium. When the vehicle speed is not medium, the erroneous coupling of the clutch 30 is determined based on whether or not the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. .

The operation and effect of this embodiment will be described.
(1) After performing the erroneous coupling determination process using the current Ic in FIG. 5, the erroneous coupling determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt in FIG. In addition, the erroneous coupling of the clutch 30 can be determined. Since the erroneous coupling of the clutch 30 is determined based on the two erroneous coupling determination processes, the determination result is further certain.

<Third Embodiment>
Hereinafter, a third embodiment of the steering apparatus will be described. Here, the difference from the first embodiment will be mainly described.

  As shown in FIG. 5, even when a situation that is considered to be an erroneous coupling of the clutch 30 occurs momentarily (YES in step S3 and YES in step S11), counting is performed by steps S4, S5, S11, and S12. Until the amount Ne becomes larger than the count amount threshold value Ne0, it is not determined that the clutch 30 is erroneously coupled. However, as shown in FIG. 7, without providing steps S4, S5, S8, S11, S12, and S15, an erroneous coupling of the clutch 30 is immediately determined when a situation considered to be an erroneous coupling of the clutch 30 occurs. You may do it.

Specifically, as shown in FIG. 7, the control device 60 determines whether or not automatic operation control is being performed (step S40).
Next, when the automatic operation control is being performed (YES in Step S40), the control device 60 determines whether or not the command to the clutch 30 is a release command (Step S41).

  When the command to clutch 30 is a release command (YES in step S41), control device 60 determines whether or not the absolute value of current Ic is sufficiently large from “0” (step S42).

  When the absolute value of current Ic is sufficiently large from “0” (YES in step S42), control device 60 determines that clutch 30 is miscoupled (step S43), and the absolute value of current Ic is “0”. Is not sufficiently large (NO in step S42), it is determined that the clutch 30 is in an open state (step S44). If the command to the clutch 30 is not a release command (NO in step S41), the control device 60 determines that the clutch 30 is in an open state (step S44).

When the automatic operation control is not being performed (NO in step S40), control device 60 determines whether or not the command to clutch 30 is a release command (step S45).
When the command to clutch 30 is a release command (YES in step S45), control device 60 determines whether the sum of steering torque Trqs and current Ic is “0” (step S46).

  When the sum of steering torque Trqs and current Ic is “0” (YES in step S46), control device 60 determines that clutch 30 is disengaged (step S47), and sum of steering torque Trqs and current Ic. Is not “0” (NO in step S46), it is determined that the clutch 30 is erroneously coupled (step S48). Further, when the command to the clutch is not the release command (NO in step S45), the control device 60 determines that the clutch 30 is in the released state (step S47).

The operation and effect of this embodiment will be described.
(1) When a situation where the clutch 30 is considered to be in an erroneously coupled state instantaneously occurs, the erroneously coupled state of the clutch 30 can be immediately determined. For this reason, the erroneous coupling of the clutch 30 can be determined more quickly.

Each embodiment may be changed as follows. Further, the following other embodiments can be combined with each other within a technically consistent range.
-In each embodiment, although the torque sensor 71 was provided between the steering wheel 10 and the reaction force motor 21, it is not restricted to this. For example, the torque sensor 71 may be provided in a portion of the first shaft 16 below the reaction force motor 21 or may be provided on the second shaft 17. In this case, the relationship between various types of information at normal time and abnormal time changes to the relationship shown in FIG. FIG. 8 shows the relationship during automatic operation control. The relationship during manual steering control is the same as in FIG. Here, the difference between FIG. 8 and FIG. 3 will be described.

  As shown in FIG. 8, when the vehicle speed is abnormal and the vehicle speed is high, the absolute value of the sum of the steering torque Trqs and the current Ic is larger than “0”. In this case, a current Ic, that is, a reaction force is generated in the same direction as the steering torque Trqs. Further, in the case of an abnormality and at a medium vehicle speed, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. At this time, the steering torque Trqs is equal to the negative current Ic. Further, when the vehicle is abnormal and the vehicle speed is low, the steering angle θa, the rotation angle θs, and the rotation angle θt are equal to each other. At this time, the absolute value of the steering torque Trqs is smaller than the absolute value of the current Ic. In this case, a current Ic, that is, a reaction force is generated in a direction opposite to the steering torque Trqs.

  In the second embodiment, after performing the erroneous coupling determination process using the current Ic in FIG. 5, the erroneous coupling determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt in FIG. 6 is performed. However, it is not limited to this. For example, the miscoupling determination process using the steering angle θa, the rotation angle θs, and the rotation angle θt in FIG. 6 may be performed before the miscoupling determination process using the current Ic in FIG.

In each embodiment, the steered side motor 41 is provided, but a hydraulic actuator may be provided instead of the steered side motor 41.
The steered side motor 41 is not limited to the rack and pinion type, and for example, the steered side motor 41 is provided so that the rack shaft 12 and the rotating shaft 41a are parallel, or the rack shaft 12 and the rotating shaft 41a. The steered side motor 41 may be provided so as to be coaxial.

  DESCRIPTION OF SYMBOLS 1 ... Steering device, 2 ... Steering mechanism, 3 ... Steering force provision mechanism, 10 ... Steering wheel (steering part), 11 ... Steering shaft, 11a ... Pinion tooth, 12 ... Rack shaft, 12a ... First rack tooth, 12b ... 2nd rack tooth, 13 ... 1st rack and pinion mechanism, 14 ... Tie rod, 15 ... Steering wheel, 16 ... 1st shaft, 17 ... 2nd shaft, 20 ... Reaction force actuator, 21 ... Reaction force motor (steering side motor) ), 21a ... rotating shaft, 22 ... reaction force side reducer, 23 ... inverter, 30 clutch 30 ... clutch, 40 ... steered actuator, 41 ... steered side motor, 42 ... steered side reducer, 43 ... second. Rack and pinion mechanism, 44 ... inverter, 45 ... pinion shaft, 46 ... rack housing, 50 ... spiral cable device, 51 ... first housing , 52 ... second housing, 53 ... cylindrical member, 54 ... spiral cable, 55 ... horn, 56 ... battery, 60 ... control device (control unit), 61 ... CPU, 62 ... memory, 70 ... steering side sensor, 71 DESCRIPTION OF SYMBOLS ... Torque sensor, 72 ... Steering side sensor, 73 ... Vehicle speed sensor, 74 ... Steering angle sensor, 75 ... Steering side current sensor, 100 ... Automatic driving control device, M2 ... Integration processing unit, M4 ... Conversion unit, M6 ... Assist Torque setting processing unit, M8 ... addition processing unit, M10 ... reaction force setting processing unit, M12 ... deviation calculation processing unit, M20 ... steering angle command value calculation processing unit, M22 ... steering angle feedback control unit, M24 ... addition processing unit, M26 ... Operation signal generation processing unit, M28 ... Steering angle ratio variable processing unit (gear ratio variable unit), M30 ... Addition processing unit, M32 ... Differential steer processing unit, M34 ... Addition processing unit, M35 ... Switching process M36, turning angle feedback control unit, M38, operation signal generation processing unit, M100, automatic operation processing unit, Δ, output value, C, viscosity coefficient, Fir, reaction force, J, inertia coefficient, V, vehicle speed, θ *: automatic operation command angle, θa: steering angle, θd: steering correction amount, θh: steering angle, θp: steering angle, θs, θt: rotation angle, θh *: steering angle command value, θp *, θp1 * Steering angle command value, θs0, θt0 ... Rotation angle, θv * ... Target operating angle, Ic, It ... Current, Kd ... Gain, MSs, MSt ... Operation signal, Trqs ... Steering torque, Trqa * ... Assist torque, Trqr *: reaction force command value, Trqt *: turning angle torque command value, Trqr1 *: feedback torque, Ne: count amount, Ne0: count amount threshold value.

Claims (5)

In a steering apparatus that executes at least one of automatic driving control and manual steering control,
A steering shaft having a first shaft and a second shaft that are separated from each other, and the rotation of the steering unit that can be rotated by the driver is transmitted to the steering shaft of the vehicle via the steering shaft. A steering mechanism that steers the steered wheels,
A clutch that mechanically connects and disconnects the first shaft and the second shaft;
A steering-side motor that applies a steering reaction force or assist force to the steering unit;
A steered side motor that imparts a steered force to the steered shaft to steer the steered wheels;
A control unit for controlling the driving of the steering side motor and the steered side motor,
The controller is configured to release the clutch based on a steering torque applied to the steering unit and a steering-side current supplied to the steering-side motor when the driver rotates. A steering device that determines whether or not the coupling is incorrect. The steering apparatus according to claim 1, wherein
The torque sensor for detecting the steering torque is a steering device provided between the steering unit and the steering-side motor. The steering apparatus according to claim 1 or 2,
The control unit executes automatic operation control, and
The control unit, during automatic operation control,
When the clutch is in an open state,
A steering device that determines that the clutch is erroneously coupled when the steering-side current is greater than a steering-side current threshold. In the steering device according to any one of claims 1 to 3,
The control unit performs manual steering control,
The control unit, during manual steering control,
When the clutch is in an open state,
A steering device that determines that the clutch is erroneously connected when the sum of the steering torque and the steering-side current is not less than a determination threshold. The steering apparatus according to claim 3 or 4,
The control unit is a steering device that determines that the clutch is erroneously connected when the state determined that the clutch is erroneously connected continues for a certain period of time.

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