JP2018094966A - Vehicle control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control device capable of transmitting a road surface state more appropriately to a driver as a steering reaction force when a vehicle is in a stop state.SOLUTION: A vehicle reaction force model 82 for a vehicle stopping state includes a first vehicle reaction force model 91 calculating a first spring reaction force torque Tbased on a target steering angle θand a second vehicle reaction force model 92 calculating a second spring reaction force torque Tbased on a current value Iof a steering motor. When an absolute value of the second spring reaction force torque Tis smaller than an absolute value of the first spring reaction force torque T, the vehicle reaction force model 82 for the vehicle stopping state uses the second spring reaction force torque Tbased on the current value Iof the steering motor as the spring reaction force torque Tfor the vehicle stopping state. The target steering angle θin which a road surface state is reflected is calculated by reflecting the second spring reaction force torque Tas the spring reaction force torque Tfor the vehicle stopping state on a basic driving torque (input torque).SELECTED DRAWING: Figure 6

Description

  The present invention relates to a vehicle control device.

  Conventionally, a so-called steer-by-wire 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. Then, the control device generates a steering reaction force through the reaction motor and turns the steered wheels through the steering motor. On the other hand, when an abnormality occurs in the reaction force motor or the like, the control device connects the clutch and maintains the state in which the steering wheel and the steered wheel are mechanically coupled. As a result, the steered wheels can be steered using the steering torque of the driver.

JP 2007-203885 A

  In the steer-by-wire type steering device, the steering wheel and the steered wheel are mechanically separated from each other, so that the road surface reaction force acting on the steered wheel is difficult to be transmitted to the steering wheel. Therefore, it is difficult for the driver to feel the road surface condition as a steering reaction force (response) felt by the hand through the steering wheel.

  Therefore, for example, it is conceivable to calculate a reaction force component corresponding to the lateral acceleration acting on the vehicle and generate a steering reaction force in consideration of the calculated reaction force component. This is because road surface conditions such as road surface frictional resistance are reflected in the lateral acceleration. However, when the vehicle is stopped, no lateral acceleration is generated in the vehicle, so that a steering reaction force reflecting the road surface condition cannot be obtained.

  An object of the present invention is to provide a vehicle control device that can more appropriately convey a road surface state to a driver as a steering reaction force when the vehicle is stopped.

  The vehicle control apparatus that can achieve the above object controls a motor that is a source of driving force applied to a steering mechanism of a vehicle based on a command value that is calculated according to a steering state. The vehicular control device includes a first calculation unit that calculates a first component of the command value according to at least a steering torque, and a target rotation angle of a rotating body that rotates in conjunction with a turning operation of a steered wheel. A second calculator that calculates based on a steering torque and a basic drive torque that is a sum of the first components, and a feedback control that matches the actual rotation angle of the rotating body with the target rotation angle. A third calculation unit that calculates two components. The second calculation unit reflects the reaction force component with respect to the basic drive torque, which is calculated based on the current value of the motor when the vehicle is in a stopped state, and then reflects the target drive angle on the basic drive torque. Is calculated.

  The road surface condition (road surface reaction force) is reflected in the current value of the motor that generates the driving force applied to the steering mechanism. For this reason, when the vehicle is in a stopped state, the target rotation angle calculated based on the basic driving torque reflecting the reaction force component based on the current value of the motor, and thus feedback control for matching the actual rotation angle to the target rotation angle The road surface state is also reflected in the second component with respect to the calculated command value. By adding this second component to the command value, the road surface state is also reflected in the driving force generated by the motor. The driver can obtain a steering reaction force according to the road surface condition as a response.

  In the above-described vehicle control device, the second calculation unit may perform a second operation on the basic driving torque based on the target rotation angle when a reaction force component based on the current value of the motor is a first reaction force component. The reaction force component may be calculated. In this case, when the second calculation unit is in a stationary state, when the value of the second reaction force component is smaller than the value of the first reaction force component, the second reaction force component is It is preferable to calculate the target rotation angle after reflecting the basic driving torque.

  The motor current value also reflects the friction of the steering mechanism. This friction tends to increase due to a decrease in the ambient temperature of the vehicle. This is because the viscosity of the grease applied to each part of the steering mechanism increases as the atmospheric temperature becomes lower. Then, as the friction of the steering mechanism increases, the steering reaction force based on the current value of the motor becomes more separated from the steering reaction force according to the actual road surface condition.

  In this regard, as described above, when the vehicle is in a stopped state, when the value of the second reaction force component is smaller than the value of the first reaction force component, the vehicle is a so-called low friction road (freezing road, snow pressure road). Etc.) is likely to stop. In such a situation, it is preferable to reflect the road surface state in the driving force generated by the motor by calculating the target rotation angle after reflecting the second reaction force component in the basic driving torque. The driver can obtain a steering reaction force according to the actual road surface condition as a response.

  In the vehicle control device, the second calculation unit uses the second reaction force component as the difference value between the first reaction force component and the second reaction force component increases. Is preferably increased.

  For example, the difference value increases as the road surface friction resistance is smaller. The first reaction force component based on the current value of the motor is increased or decreased according to the increase or decrease of the road surface frictional resistance. The driver feels a finer change in the steering reaction force as a response, thereby making it easier to grasp the road surface condition.

  In the above-described vehicle control device, the steering mechanism includes a pinion shaft as the rotating body that is mechanically separated from the steering wheel, and a steering wheel that steers the steered wheels in conjunction with the rotation of the pinion shaft. A rudder shaft may be included. Further, as a control target of the vehicle control device, a reaction force motor that generates a steering reaction force that is a torque in a direction opposite to a steering direction as the driving force applied to the steering wheel based on the command value, and the pinion shaft Alternatively, a steering motor that generates a steering force for turning the steered wheels provided to the steered shaft may be included. In this case, the second calculation unit reflects the reaction force component with respect to the basic drive torque, which is calculated based on the current value of the steered motor when the vehicle is stopped, in the basic drive torque. It is preferable to calculate the target rotation angle.

According to this configuration, when the vehicle is stopped, a steering reaction force corresponding to the road surface state can be generated through the control of the reaction force motor.
In the above vehicle control device, the steering mechanism may include a pinion shaft as the rotating body interlocked with a steering wheel and a steering shaft that steers the steered wheels in association with rotation of the pinion shaft. Good. In this case, the motor is preferably an assist motor that generates a steering assist force that is a torque in the same direction as the steering direction as the driving force applied to the steering wheel.

  According to this configuration, when the vehicle is stopped, a steering reaction force according to the road surface state can be generated through the control of the assist motor.

  According to the vehicle control device of the present invention, when the vehicle is stopped, the road surface state can be more appropriately transmitted to the driver as the steering reaction force.

The block diagram of the steering device by which 1st Embodiment of the control apparatus for vehicles is mounted. The control block diagram of the electronic control apparatus concerning 1st Embodiment. The control block diagram of the target rudder angle calculating part concerning 1st Embodiment. The control block diagram of the ideal vehicle model concerning 1st Embodiment. The graph which shows the vehicle speed gain map concerning 1st Embodiment. The control block diagram of the vehicle reaction force model for the time of a stop concerning 1st Embodiment. The graph which shows the characteristic of the 1st vehicle reaction force model concerning a 1st embodiment. The graph which shows the characteristic of the 2nd vehicle reaction force model concerning 1st Embodiment. The graph which shows the distribution gain map concerning 1st Embodiment. The graph which shows an example of the magnitude relationship of the 1st vehicle reaction force concerning 1st Embodiment, and the 2nd vehicle reaction force. The block diagram of the steering device by which 2nd Embodiment of the control apparatus for vehicles is mounted. The control block diagram of the electronic control apparatus concerning 1st Embodiment.

<First Embodiment>
Hereinafter, a first embodiment in which the vehicle control device is applied to a steer-by-wire steering device will be described.

  As shown in FIG. 1, the vehicle steering apparatus 10 includes a steering shaft 12 connected to a steering wheel 11. A pinion shaft 13 is provided at the end of the steering shaft 12 opposite to the steering wheel 11. The pinion teeth 13 a of the pinion shaft 13 are meshed with the rack teeth 14 a of the steered shaft 14 extending in a direction intersecting with the pinion shaft 13. Left and right steered wheels 16 and 16 are connected to both ends of the steered shaft 14 via tie rods 15 and 15, respectively. The steering shaft 12, the pinion shaft 13, and the steered shaft 14 function as a power transmission path between the steering wheel 11 and the steered wheels 16 and 16. That is, the turning angle θt of the steered wheels 16 and 16 is changed by the linear movement of the steered shaft 14 accompanying the rotation operation of the steering wheel 11.

<Clutch>
In addition, the steering device 10 includes a clutch 21 and a clutch control unit 22.
The clutch 21 is provided in the middle of the steering shaft 12. As the clutch 21, an electromagnetic clutch that engages / disengages power through energization of the exciting coil is employed. When the clutch 21 is disconnected, the power transmission path between the steering wheel 11 and the steered wheels 16 and 16 is mechanically disconnected. When the clutch 21 is connected, the power transmission between the steering wheel 11 and the steered wheels 16 and 16 is mechanically coupled.

  The clutch control unit 22 controls the engagement / disengagement of the clutch 21. The clutch control unit 22 switches the clutch 21 from the connected state to the disconnected state by energizing the exciting coil of the clutch 21. The clutch control unit 22 switches the clutch 21 from the disconnected state to the connected state by stopping energization of the excitation coil of the clutch 21.

<Configuration for generating steering reaction force: reaction force unit>
Further, the steering device 10 includes a reaction force motor 31, a speed reduction mechanism 32, a rotation angle sensor 33, a torque sensor 34, and a reaction force control unit 35 as a configuration for generating a steering reaction force. Incidentally, the steering reaction force refers to a force (torque) acting in a direction opposite to the direction in which the driver operates the steering wheel 11. By applying the steering reaction force to the steering wheel 11, it is possible to give the driver a moderate feeling of response.

  The reaction force motor 31 is a generation source of the steering reaction force. As the reaction force motor 31, for example, a three-phase (U, V, W) brushless motor is employed. The reaction force motor 31 (more precisely, its rotating shaft) is connected to the steering shaft 12 via a speed reduction mechanism 32. The speed reduction mechanism 32 is provided in a portion of the steering shaft 12 closer to the steering wheel 11 than the clutch 21. The torque of the reaction force motor 31 is applied to the steering shaft 12 as a steering reaction force.

The rotation angle sensor 33 is provided in the reaction force motor 31. Rotation angle sensor 33 detects the rotation angle theta _a reaction force motor 31. Rotation angle theta _a reaction force motor 31 is used in the calculation of the steering angle theta _{s (the} steering angle). The reaction force motor 31 and the steering shaft 12 are linked via a speed reduction mechanism 32. Therefore, the rotation angle of the rotation angle theta _a and the steering shaft 12 of the reaction force motor 31, between the steering angle theta _s is therefore the rotation angle of the steering wheel 11 are correlated. Therefore, the steering angle θ _s can be obtained based on the rotation angle θ _a of the reaction force motor 31.

The torque sensor 34 detects the steering torque T _h applied to the steering shaft 12 through a rotational operation of the steering wheel 11. The torque sensor 34 is provided in a portion of the steering shaft 12 closer to the steering wheel 11 than the speed reduction mechanism 32.

Reaction force control unit 35 executes the reaction force control for generating the steering reaction force corresponding to the steering torque T _h through the drive control of the reaction motor 31. In addition, the reaction force control unit 35 executes intermittent control for switching the connection of the clutch 21 based on the success or failure of the clutch connection condition. An example of the clutch connection condition is that the power switch of the vehicle is turned off. The reaction force control unit 35 generates a command signal to connect the clutch 21 when the clutch connection condition is satisfied, and generates a command signal to disconnect the clutch when the clutch connection condition is not satisfied. The clutch control unit 22 controls the on / off of the clutch 21 based on the command signal generated by the reaction force control unit 35.

<Configuration for generating steering force: Steering unit>
In addition, the steering device 10 is configured to generate a turning force that is power for turning the steered wheels 16 and 16, as a turning motor 41, a speed reduction mechanism 42, a rotation angle sensor 43, and turning control. A portion 44 is provided.

  The steered motor 41 is a source of turning force. As the steered motor 41, for example, a three-phase brushless motor is employed. The steered motor 41 (more precisely, its rotating shaft) is connected to the pinion shaft 13 via a speed reduction mechanism 42. The torque of the turning motor 41 is applied to the turning shaft 14 through the pinion shaft 13 as a turning force. In accordance with the rotation of the turning motor 41, the turning shaft 14 moves along the vehicle width direction (left-right direction in the figure).

The rotation angle sensor 43 is provided in the steering motor 41. Rotation angle sensor 43 detects the rotation angle theta _b steering motors 41.
The steered control unit 44 performs steered control that steers the steered wheels 16 and 16 according to the steering state through drive control of the steered motor 41. In this example, the steered wheels 16 and 16 are steered as much as the steering wheel 11 is operated. That is, in order to match the actual steered angle θt to the steering angle theta _s of the steering wheel 11 powered to the steering motor 41 is controlled.

<Reaction force control unit>
Next, the reaction force control unit 35 will be described in detail.
As shown in FIG. 2, the reaction force control unit 35 includes a target steering reaction force calculation unit 51, a target steering angle calculation unit 52, a steering angle calculation unit 53, a steering angle feedback control unit 54, an adder 55, and an energization control unit. 56.

Target steering reaction force calculation unit 51 calculates the target steering reaction force T ₁ ^* based on the steering torque T _h. The target steering reaction force calculation unit 51 may calculate the target steering reaction force T ₁ ^* in consideration of the vehicle speed V.

The target rudder angle calculation unit 52 calculates the target rudder angle θ ^* of the steering wheel 11 based on the target steering reaction force T ₁ ^* , the steering torque _Th, and the vehicle speed V. Target steering angle calculating section 52, when the sum of the target steering reaction force T ₁ ^* and the steering torque T _h a basic drive torque (input torque), the ideal model to determine the ideal steering angle on the basis of the basic drive torque have. This ideal model is obtained by modeling the steering angle corresponding to the ideal turning angle according to the basic driving torque in advance by experiments or the like. The target rudder angle calculation unit 52 obtains the basic drive torque by adding the target steering reaction force T ₁ ^* and the steering torque _Th , and calculates the target rudder angle θ ^* from the basic drive torque based on the ideal model. .

The steering angle calculator 53 calculates the actual steering angle θ _s of the steering wheel 11 based on the rotation angle θ _a of the reaction force motor 31 detected through the rotation angle sensor 33. Steering angle feedback control section 54 calculates the actual steering angle theta _s steering angle correction amount through feedback control of the steering angle theta _s in order to follow the target steering angle theta ^* a T ₂ ^*. The adder 55 calculates the steering reaction force command value T ^* by the target steering reaction force T ₁ ^* adds the steering angle correction amount T ₂ ^*.

The energization control unit 56 supplies power corresponding to the steering reaction force command value T ^* to the reaction force motor 31. Specifically, the energization control unit 56 calculates a current command value for the reaction force motor 31 based on the steering reaction force command value T ^* . Further, power supply controller 56 through the current sensor 57 provided in the feed path for the reaction force motor 31, to detect the actual current values I _a generated to the power supply path. This current value _Ia is a value of an actual current supplied to the reaction force motor 31. The power supply controller 56 obtains the deviation of the actual current value I _a current command value, and controls the power supply to the reaction force motor 31 so as to eliminate the deviation (feedback control of the current I _a). Thereby, the reaction force motor 31 generates torque according to the steering reaction force command value T ^* . It is possible to give the driver an appropriate feeling of response according to the road surface reaction force.

<Steering control unit>
Next, the steering control unit 44 will be described in detail.
As shown in FIG. 2, the steering control unit 44 includes a pinion angle calculation unit 61, a pinion angle feedback control unit 62, and an energization control unit 63.

Pinion angle calculating section 61 calculates the pinion angle theta _p is the actual rotation angle of the pinion shaft 13 based on the rotation angle theta _b of the steering motor 41 which is detected through the rotational angle sensor 43. As described above, the steered motor 41 and the pinion shaft 13 are linked via the speed reduction mechanism 42. Therefore, there is a correlation between the rotation angle theta _b and the pinion angle theta _p of the steering motor 41. Using this correlation can be obtained pinion angle theta _p from the rotation angle theta _b steering motors 41. Further, as described above, the pinion shaft 13 is meshed with the steered shaft 14. Therefore, there is also a correlation between the pinion angle theta _p and the amount of movement of the steered shaft 14. That is, the pinion angle theta _p is a value that reflects the steered angle θt of the steered wheels 16, 16.

The pinion angle feedback control unit 62 takes in the target steering angle θ ^* calculated by the target steering angle calculation unit 52 as the target pinion angle. Pinion angle feedback control section 62 calculates the pinion angle command value T _theta ^* through actual feedback control of the pinion angle theta _p in order to follow the target steering angle theta ^* of the pinion angle theta _p as the target pinion angle.

The energization control unit 63 supplies power to the steered motor 41 according to the pinion angle command value T _θ ^* . Specifically, the energization control unit 63 calculates a current command value for the steered motor 41 based on the pinion angle command value T _θ ^* . Further, power supply controller 63 through the current sensor 64 provided on the feeding path for the steering motor 41, to detect the actual current value I _b occurring to the power supply path. This current value _Ib is a value of an actual current supplied to the steered motor 41. The power supply controller 63 obtains the deviation of the actual current value I _b between the current command value, and controls the power supply to the steering motor 41 so as to eliminate the deviation (feedback control of the current I _b). Thereby, the steered motor 41 rotates by an angle corresponding to the pinion angle command value _Tθ ^* . That is, the steered wheels 16 and 16 are steered as much as the steering wheel 11 is operated.

<Target rudder angle calculation unit>
Next, the target rudder angle calculation unit 52 will be described in detail.
As described above, the target steering angle calculating section 52 calculates the target steering angle theta ^* based from the target steering reaction force T ₁ ^* and the sum which is the basic drive torque of the steering torque T _h the ideal model. This ideal model is a model that utilizes the fact that the basic drive torque T _in ^* as the torque applied to the steering shaft 12 is expressed by the following equation (A).

T _in ^* = Jθ ^{* ′ ′} + Cθ ^{* ′} + Kθ ^* (A)
However, "J" is the moment of inertia of the steering wheel 11 and the steering shaft 12, "C" is a viscosity coefficient (friction coefficient) corresponding to friction with respect to the housing of the steered shaft 14, and "K" is the steering wheel 11 and the steering shaft. This is a spring coefficient when 12 is regarded as a spring.

As seen from equation (A), ^* the basic drive torque T _in, the target steering angle theta ^* a second-order time differential value theta ^{* ''} to a value obtained by multiplying the inertia moment J, the target steering angle theta ^* first-order time differential It is obtained by adding a value obtained by multiplying the value θ ^* ′ by the viscosity coefficient C and a value obtained by multiplying the target steering angle θ ^* by the spring coefficient K. The target rudder angle calculation unit 52 calculates the target rudder angle θ ^* according to an ideal model based on the formula (A).

As shown in FIG. 3, the ideal model based on the formula (A) is divided into an ideal steering model 71 and an ideal vehicle model 72.
The ideal steering model 71 is tuned according to the characteristics of each component of the steering device 10 such as the steering shaft 12 and the reaction force motor 31. The ideal steering model 71 includes an adder 73, a subtracter 74, an inertia model 75, a first integrator 76, a second integrator 77, and a viscosity model 78.

The adder 73 calculates the basic drive torque _{T in} ^* by adding the target steering reaction force _T ^{1 *} and the steering torque _{T h.}
The subtracter 74 calculates a final basic drive torque T _in ^* by subtracting a viscosity component T _vi ^* and a spring component T _sp ^*, which will be described later, from the basic drive torque T _in ^* calculated by the adder 73, respectively. To do.

The inertia model 75 functions as an inertia control calculation unit corresponding to the inertia term of the equation (A). The inertia model 75 calculates the steering angular acceleration α ^* by multiplying the final basic drive torque T _in ^* calculated by the subtractor 74 by the inverse of the inertia moment J.

The first integrator 76 calculates the steering angular velocity ω ^* by integrating the steering angular acceleration α ^* calculated by the inertia model 75.
The second integrator 77 further calculates the target steering angle θ ^* by further integrating the steering angular velocity ω ^* calculated by the first integrator 76. The target rudder angle θ ^* is an ideal rotation angle of the steering wheel 11 (steering shaft 12) based on the ideal steering model 71.

The viscosity model 78 functions as a viscosity control calculation unit corresponding to the viscosity term of Expression (A). The viscosity model 78 calculates the viscosity component T _vi ^* of the basic drive torque T _in ^* by multiplying the steering angular velocity ω ^* calculated by the first integrator 76 by the viscosity coefficient C.

The ideal vehicle model 72 is tuned according to the characteristics of the vehicle on which the steering device 10 is mounted. The vehicle-side characteristics that affect the steering characteristics are determined by, for example, the specifications of the suspension and wheel alignment, the grip force (friction force) of the steered wheels 16 and 16, and the like. The ideal vehicle model 72 functions as a spring characteristic control calculation unit corresponding to the spring term of the formula (A). The ideal vehicle model 72 calculates the spring component T _sp ^* of the basic drive torque T _in ^* by multiplying the target steering angle θ ^* calculated by the second integrator 77 by the spring coefficient K. Incidentally, the ideal vehicle model 72, when calculating the spring component T _sp ^*, is to the current value I _b of the steering motor 41 that is detected through the vehicle speed V and a current sensor 64, respectively.

According to the target rudder angle calculation unit 52 configured in this way, the basic drive torque T _in ^{* is} obtained by adjusting the moment of inertia J and the viscosity coefficient C of the ideal steering model 71 and the spring coefficient K of the ideal vehicle model 72, respectively ^. And the target steering angle θ ^* can be directly tuned, and thus desired steering characteristics can be realized. In this example, the target steering angle θ ^* calculated from the basic driving torque T _in ^{* based} on the ideal steering model 71 and the ideal vehicle model 72 is used as the target pinion angle. Then, the feedback control so that the actual pinion angle theta _p matches the target steering angle as a target pinion angle theta ^*. As described above, there is a correlation between the pinion angle theta _p and the steered angle theta _t of the steered wheels 16, 16. For this reason, the steering operation of the steered wheels 16 and 16 according to the basic drive torque T _in ^* is also determined by the ideal steering model 71 and the ideal vehicle model 72. That is, the steering feeling of the vehicle is determined by the ideal steering model 71 and the ideal vehicle model 72. Therefore, a desired steering feeling can be realized by adjusting the ideal steering model 71 and the ideal vehicle model 72.

However, the steering reaction force (responsiveness felt through the steering), which is a force (torque) acting in the direction opposite to the steering direction of the driver, only depends on the target steering angle θ ^* . That is, the steering reaction force does not change depending on the road surface condition (such as ease of slipping on the road surface). For this reason, it is difficult for the driver to grasp the road surface state through the steering reaction force. Therefore, in this example, the ideal vehicle model 72 is configured as follows based on the viewpoint of eliminating such concerns. In this example, measures are mainly taken when the vehicle is stopped.

<Ideal vehicle model>
As shown in FIG. 4, the ideal vehicle model 72 includes a vehicle reaction force model 81 for traveling, a vehicle reaction force model 82 for stopping, a vehicle speed gain calculation unit 83, and a switching unit 84.

The vehicle reaction force model 81 for traveling calculates the spring reaction force torque T _sp1 ^* for traveling. The spring reaction force torque T _sp1 ^* for traveling is a steering reaction force component (reaction force component to be applied to the steering) corresponding to the target rudder angle θ ^* , and contributes to the steering rigidity (solid feeling). . The vehicle reaction force model 81 for traveling takes in the target rudder angle θ ^* calculated by the second integrator 77, and multiplies the taken-in target rudder angle θ ^* by a spring coefficient to obtain the target rudder angle θ ^*. The spring reaction force torque T _sp1 ^* for traveling according to the above is calculated.

Note that the lateral acceleration reflects road surface conditions such as road surface frictional resistance, and the vehicle reaction force model 81 for traveling may be configured as follows. That is, the vehicle reaction force model 81 for traveling calculates a steering reaction force component according to the lateral acceleration acting on the vehicle, and takes into account the calculated reaction force component, and the spring reaction force torque T _sp1 for traveling. ^* May be calculated. More specifically, for example, the vehicle reaction force model 81 for traveling corresponds to the spring reaction force torque T _sp1 ^* for traveling, which is a steering reaction force component corresponding to the target steering angle θ ^* , and the lateral acceleration. A difference value (absolute value) from the steering reaction force component is calculated, and the use ratio of the steering reaction force component corresponding to the lateral acceleration is increased as the difference value increases. When the vehicle is traveling on a low friction road, the difference value tends to increase as the road surface friction resistance becomes smaller. When the use ratio of the steering reaction force component according to the lateral acceleration is increased or decreased according to the increase or decrease of the road surface frictional resistance, the spring reaction force torque T _sp1 ^* for traveling more reflects the road surface condition. .

The vehicle reaction force model 82 used when the vehicle is stopped calculates a spring reaction force torque _Tsp2 ^* used when the vehicle is stopped. Spring for when the vehicle is stopped reaction torque T _sp2 ^* is a steering reaction force component corresponding to the current value I _b of the current supplied to the target steering angle theta ^* and the steering motor 41, the road surface in an actual vehicle It has characteristics close to reaction force. Vehicle for when the vehicle is stopped reaction force model 82 captures the current value I _b of the current supplied to the target steering angle theta ^* and the steering motor 41 based on these target steering angle is taken theta ^* and the current value I _b, The spring reaction force torque T _sp2 ^* for stopping is calculated.

Vehicle speed gain computing section 83 computes the vehicle speed gain G _v using the vehicle speed gain map 85 with itself. Vehicle speed gain map 85 is for defining the relationship between vehicle speed V and vehicle speed gain G _v, for during running spring reaction force torque T _sp1 ^* and for when the vehicle is stopped the spring reaction force torque T _sp2 ^* in either Used to determine whether the value is used as the spring component T _sp ^* . The vehicle speed gain _Gv is set to a value in the range of “0” to “1” according to the vehicle speed V.

As shown in the graph of FIG. 5, when the vehicle speed V is plotted on the horizontal axis and the vehicle speed gain _Gv is plotted on the vertical axis, the vehicle speed gain map 85 has the following characteristics. That is, when the vehicle speed V is less than the first vehicle speed threshold value V _th1 with “0” as a reference, the vehicle speed gain G _v is set to “0”. After the vehicle speed V reaches a certain value, when the vehicle speed V is less than the second vehicle speed threshold value _Vth2 , the vehicle speed gain _Gv is set to a larger value as the vehicle speed V increases. When the vehicle speed V is _{equal to} or higher than the second vehicle speed threshold value _Vth2 , the vehicle speed gain _Gv is set to “1”.

As shown in FIG. 4, the switching unit 84 takes in a spring reaction force torque T _sp1 ^* for traveling and a spring reaction force torque T _sp2 ^* for stopping as data inputs. The switching unit 84, as a control input, captures the vehicle speed gain _{G v.} Switching unit 84 on the basis of the value of the vehicle speed gain _{G v,} the value supplied to the subtractor 74, between the spring reaction force torque _{T sp1} ^* for during running, the spring reaction force torque _{T sp2} ^* for when the vehicle is stopped Switch with. Switching unit 84, when the value of the vehicle speed gain _{G v} is "0", and supplies to the subtractor 74 the spring reaction force torque _{T sp2} ^* for when the vehicle is stopped as a spring component _{T sp} ^*. Switching unit 84, not equal the value of the vehicle speed gain _{G v} is "0", supplies the spring reaction force torque _{T sp1} ^* for during running to the spring component _{T sp} ^* as a subtracter 74.

<Vehicle reaction force model for stopping>
Next, the vehicle reaction force model 82 for stopping will be described in detail.
As shown in FIG. 6, the vehicle reaction force model 82 for stopping is composed of a first vehicle reaction force model 91, a second vehicle reaction force model 92, a distribution gain calculation unit 93, and a reaction force torque calculation unit 94. Have.

The first vehicle reaction force model 91 takes in the target rudder angle θ ^* calculated by the second integrator 77, and calculates the first spring reaction force torque _Tsp21 ^* based on the taken in target rudder angle θ ^*. To do. The first vehicle reaction force model 91 calculates the first spring reaction force torque T _sp21 ^* using the first reaction force map 95 possessed by itself.

As shown in the graph of FIG. 7, when the target rudder angle θ ^* is plotted on the horizontal axis and the first spring reaction force torque _Tsp21 ^* is plotted on the vertical axis, the first reaction force map 95 has the following characteristics. Have That is, as the absolute value of the first spring reaction force torque _Tsp21 ^* increases, the absolute value of the first spring reaction force torque _Tsp21 ^* is set to a larger value.

As shown in FIG. 6, the second vehicle reaction force model 92 captures the current value I _b of the steering motor 41 which is detected through the current sensor 64, the taken on the basis of the current value I _b is the second spring reaction The force torque T _sp22 ^* is calculated. The second vehicle reaction force model 92 calculates the second spring reaction force torque T _sp22 ^* using the second reaction force map 96 possessed by itself. Road reaction force is reflected in the current value I _b of the turning motor 41. Therefore, the second spring reaction force torque T _sp22 ^* calculated based on the current value _Ib is in accordance with the road surface reaction force.

As shown in the graph of FIG. 8, when the current value _Ib is plotted on the horizontal axis and the second spring reaction force torque _Tsp22 ^* is plotted on the vertical axis, the second reaction force map 96 has the following characteristics. Have. That is, as the absolute value of the current I _b is increased, the absolute value of the second spring reaction force torque T _SP22 ^* is set to a larger value.

As shown in FIG. 6, the distribution gain calculation unit 93 calculates the first spring reaction force torque T _sp21 ^* calculated by the first vehicle reaction force model 91 and the second vehicle reaction force model 92. based on the second spring reaction force torque _{T SP22} ^*, it calculates the distribution gain _{G d.}

As shown in the following equation (B), the distribution gain calculation unit 93 calculates a difference value T between the absolute value of the first spring reaction force torque T _sp21 ^{* and} the absolute value of the second spring reaction force torque T _sp22 ^*. Calculate _δ ^* .

_{^{T δ * = │T sp21 * │}} -│T sp22 * │ ... (B)
Distribution gain calculation unit 93, based on the difference value T _[delta] ^*, which is calculated based on the equation (B), it calculates the distribution gain G _d using distribution gain map 97 itself has. Distribution gain map 97 defines the relationship between the difference value T _[delta] ^* and distribution gain G _d. Distribution gain _{G d} is used to determine the use ratio of the first spring reaction force torque _{T SP21} ^* and the second spring reaction force torque _{T SP22} ^*.

As shown in the graph of FIG. 9, when the difference value T _δ ^* is plotted on the horizontal axis and the distribution gain G _d is plotted on the vertical axis, the distribution gain map 97 has the following characteristics. That is, when the difference value _Tδ ^* is a negative value, the distribution gain _Gd is set to “0”. When the difference value T _δ ^* is greater than or equal to “0” and less than the difference value threshold value T _δth ^* , the distribution gain G _d is set to a larger value as the difference value T _δ ^* increases. When the difference value T _δ ^* is greater than or equal to the difference value threshold value T _δth ^* , the distribution gain G _d is set to “1”. The distribution gain _Gd is set to a value in the range of “0” to “1” according to the difference value T _δ ^* .

As shown in FIG. 6, the reaction force torque computing section 94 uses the distribution gain G _d, which is calculated by the distribution gain calculation unit 93, a first spring reaction force torque T _SP21 ^* and the second spring reaction force A use ratio with the torque T _sp22 ^* is determined, and a spring reaction force torque T _sp2 ^* for stopping is calculated based on the use ratio. The spring reaction force torque T _sp2 ^* for stopping is obtained by the following equation (C).

_{^{T sp2 * = T sp22 * ·}} (1-G d) + T sp21 * · G d ... (C)
In the formula (C), the distribution gain _Gd is set to a value from “0” to “1” according to the difference value T _δ ^* . When distribution gain _{G d} is "0", the use ratio of the second spring reaction force torque _{T SP22} ^* is 100%. When distribution gain _{G d} is "1", the use ratio of the first spring reaction force torque _{T SP21} ^* is 100%. When distribution gain _{G d} is a value between "1" and "0", the first spring reaction force torque _{T SP21} ^* and the second spring reaction force torque _{T SP22} ^*, respectively distribution gain _{G d} It is added at the usage ratio according to the value of. In this manner, the first spring reaction force torque _{T SP21} ^* and the use ratio of the second spring reaction force torque _{T SP22} ^* according to the value of the distribution gain _{G d} is adjusted.

<Operation and effect of ideal vehicle model>
Next, the operation and effect of the ideal vehicle model 72 will be described separately when the vehicle is running and when the vehicle is stopped.

<During driving>
First, the case where the vehicle is traveling will be described. As shown in the graph of FIG. 5, when the vehicle speed V is _{equal to} or higher than the first vehicle speed threshold value V _th1 and _lower than the second vehicle speed threshold value V _th2 , the vehicle speed gain G _v exceeds “0”, and It is set to a value less than “1”. Further, when the vehicle speed V is _{equal to} or higher than the second vehicle speed threshold value _Vth2 , the vehicle speed gain _Gv is set to “1”. As shown in FIG. 4, when the vehicle speed gain G _v is not “0”, the switching unit 84 selects the spring reaction force torque T _sp1 ^* for traveling as the spring component T _sp ^* of the basic drive torque T _in ^*. To do. The spring reaction force torque T _sp1 ^* for traveling is a steering reaction force component corresponding to the target steering angle θ ^* . For this reason, a steering reaction force according to the target rudder angle θ ^* is applied to the steering wheel 11.

As described above, as the vehicle reaction force model 81 for traveling, a configuration is adopted in which the spring reaction force torque T _sp1 ^* for traveling is calculated in consideration of the steering reaction force component corresponding to the lateral acceleration acting on the vehicle. In this case, the steering reaction force component that increases or decreases in accordance with the lateral acceleration is added, and the spring reaction force torque T _sp1 ^* for traveling is used as the spring component T _sp ^* of the basic drive torque T _in ^* . For this reason, the target rudder angle θ ^* and consequently the rudder angle correction amount T ₂ ^* calculated by the rudder angle feedback control unit 54 reflects the road surface condition (road surface frictional resistance). Accordingly, a steering reaction force corresponding to the road surface condition is applied to the steering wheel 11.

<When stopped>
Next, a case where the vehicle is stopped will be described. As shown in the graph of FIG. 5, when the vehicle speed V is less than the first vehicle speed threshold value V _th1 , the vehicle speed gain _Gv is set to “0”. As shown in FIG. 4, when the vehicle speed gain G _v is “0”, the switching unit 84 uses the spring reaction force torque T _sp2 ^* for stopping as the spring component T _sp ^* of the basic drive torque T _in ^*. select.

Here, it _seems that the second spring reaction force torque T _sp22 ^* may always be used as the stopping spring reaction force torque T _sp2 ^* . Since this ^* the second spring reaction torque T _SP22, a steering reaction force component corresponding to the current value I _b of the steering motor 41 to the actual road surface reaction force acting on the steered wheels 16, 16 is reflected It is. For this reason, by using the second spring reaction force torque T _sp22 ^{* as} the spring component T _sp ^* of the basic drive torque T _in ^* , a steering reaction force corresponding to the actual road surface condition is applied to the steering wheel 11. The

However, the current value I _b of the steering motor 41, the friction to the turning shaft 14 starts moving (meshing portion of the gears, friction in such bearings and rack guide portion) is also reflected. Therefore, current I _b of the turning motor 41 that is detected through the current sensor 64 can not be said that actual axial force applied to the steering shaft 14 (road surface reaction force) is reflected purely. Here, as the ambient temperature around the vehicle becomes lower, the friction until the steered shaft 14 starts to move tends to increase. This is because the viscosity of the grease applied to the meshing portion of the gear increases as the ambient temperature becomes lower. As the friction until the steered shaft 14 starts to move increases, the steering reaction force based on the second spring reaction force torque _Tsp22 ^* is more deviated from the steering reaction force according to the actual road surface condition. It becomes. It may also lead to a decrease in steering feeling.

Therefore, in this example, when the _vehicle is stopped, the second spring reaction force based on the absolute value of the first spring reaction torque T _sp21 ^* based on the target rudder angle θ ^* and the current value I _b of the steering motor 41. based on the difference between the torque _{T SP22} ^* absolute value, using either the first spring reaction force torque _{T SP21} ^* and the second spring reaction force torque _{T SP22} ^* as a spring reaction force torque _{T sp2} ^* for during vehicle stop Decide what to do.

As shown in the graph of FIG. 10, when the absolute value of the first spring reaction force torque _{T SP21} ^* than the absolute value second spring reaction force torque _{T SP22} ^* is small, the following equation (B1) is satisfied . At this time, the second spring reaction force torque _{T SP22} ^* is used as the spring reaction force torque _{T sp2} ^* for when the vehicle is stopped based on the current value _{I b} of the turning motor 41.

_{^{T δ * = │T sp21 * │}} -│T sp22 * │> 0 ( to be ^{_{precise, T δth *) ... (B1}} )
As a situation in which the formula (B1) is established, for example, a situation in which the vehicle is stopped on a so-called low friction road (such as a frozen road, a snowy road, etc.) can be considered. In this case, the road surface reaction force acting on the steered wheels 16 and 16 is weaker than when the vehicle is stopped on a dry road such as asphalt. For this reason, the current value Ib of the steered motor 41 is also a smaller value. When there is a high probability that such a vehicle is stopped on a road surface condition such as a low friction road, it is preferable to apply a steering reaction force according to the actual road surface condition to the steering wheel 11. By the second spring reaction torque T _SP22 based on the current value I _b of the turning motor 41 ^* is used as the spring reaction force torque T _sp2 ^* for when the vehicle is stopped, road surface condition (here, low friction road) Therefore, the driver can easily grasp the road surface condition as a response.

In addition, the difference value _Tδ ^* becomes a larger value as the road surface friction resistance is smaller. Second spring reaction force torque T _SP22 ^* use ratio based on the current value I _b of the steering motor 41 in accordance with the increase or decrease of the road surface frictional resistance is increased or decreased. The driver feels a finer change in the steering reaction force as a response, thereby making it easier to grasp the road surface condition.

As shown in the graph of FIG. 10, when the absolute value of the first spring reaction force torque _{T SP21} ^* than the absolute value second spring reaction force torque _{T SP22} ^* is large, the following equation (B2) is satisfied . At this time, the first spring reaction torque T _sp21 ^* based on the target steering angle θ ^* is used as the spring reaction torque T _sp2 ^* for stopping.

_{^{T δ * = │T sp21 * │}} -│T sp22 * │ <0 ... (B2)
The situation where the formula (B2) is satisfied is, for example, the first situation where the vehicle is stopped on a dry road where the road surface friction resistance is larger than that on the low friction road, or the case where the vehicle is stopped on a low friction road. However, a second situation in which the friction until the steered shaft 14 starts to move with the decrease in the atmospheric temperature described above can be considered. First situation and where you do not know any of the situations of the second situation, if the case is a second situation, the anti-second spring based on current value I _b of the steering motor 41 which is calculated in this situation When the torque _T sp22 ^* is used as a spring reaction force torque T _sp2 ^* for when the vehicle is stopped, steering reaction force deviation between the actual road conditions rather that it could be applied to the steering wheel 11. Therefore, when the expression (B2) is satisfied, it is preferred to use a first spring reaction force torque _T based on the target steering angle theta ^* _SP21 ^* as the spring reaction force torque _{T sp2} ^* for when the vehicle is stopped. The steering wheel 11 is continuously applied with a steering reaction force that reflects the first spring reaction force torque _Tsp21 ^* based on the target steering angle θ ^* , so that the driver can obtain a steering feeling that is the same as before. It is done. Robustness against friction at the meshing portion of the gear is improved.

<Second Embodiment>
Hereinafter, a second embodiment in which the vehicle control device is applied to an electric power steering device (EPS) will be described. In addition, the same code | symbol is attached | subjected about the member similar to 1st Embodiment, and the detailed description is omitted.

  As shown in FIG. 11, the EPS 100 includes a steering shaft 12, a pinion shaft 13, and a steered shaft 14 that function as a power transmission path between the steering wheel 11 and the steered wheels 16 and 16. The reciprocating linear motion of the steered shaft 14 is transmitted to the left and right steered wheels 16 and 16 via tie rods 15 respectively connected to both ends of the steered shaft 14.

The EPS 100 includes an assist motor 101, a speed reduction mechanism 102, a torque sensor 34, a rotation angle sensor 103, and an assist control unit 104 as a configuration for generating a steering assist force (assist force). Rotation angle sensor 103 is provided in the assist motor 101, and detects the rotation angle theta _m.

  The assist motor 101 is a source of steering assist force, and for example, a three-phase brushless motor is employed. The assist motor 101 is connected to the pinion shaft 13 via the speed reduction mechanism 102. The rotation of the assist motor 101 is decelerated by the decelerating mechanism 102, and the decelerated rotational force is transmitted to the pinion shaft 13 as a steering assist force.

Assist control unit 104 executes the assist control for generating a steering assist force corresponding to the steering torque T _h through energization control for the assist motor 101. The assist control unit 104 controls power supply to the assist motor 101 based on the steering torque T _h detected through the torque sensor 34, the vehicle speed V detected through the vehicle speed sensor 36, and the rotation angle θ _m detected through the rotation angle sensor 103. To do.

  As shown in FIG. 12, the assist control unit 104 includes a pinion angle calculation unit 110, a basic assist component calculation unit 111, a target pinion angle calculation unit 112, a pinion angle feedback control unit (pinion angle F / B control unit) 113, and addition. And an energization control unit 115.

Pinion angle computation unit 110 takes in the rotation angle theta _m of the assist motor 101, computes the pinion angle theta _p is the rotation angle of the pinion shaft 13 based on the rotation angle theta _m This incorporated.

The basic assist component calculation unit 111 calculates a basic assist component _Ta1 ^* based on the steering torque _Th and the vehicle speed V. Basic assist component calculating unit 111 uses the three-dimensional map that defines the relationship between the steering torque T _h and the basic assist component T _a1 ^* in accordance with the vehicle speed V, the calculating a basic assist component T _a1 ^*. Basic assist component calculating unit 111, the larger the absolute value of the steering torque T _h is, or as the vehicle speed V is slow, and sets the absolute value of the basic assist component T _a1 ^* to a larger value.

Target pinion angle computation unit 112 ^* basic assist component calculating unit 111 basic assist component is calculated by _{T a1,} and captures the steering torque _{T h.} Target pinion angle computation unit 112, when the sum of the basic assist component T _a1 ^* and the steering torque T _h a basic drive torque (input torque), have a ideal model to determine the ideal pinion angle based on the basic drive torque doing. In the ideal model, a pinion angle corresponding to an ideal turning angle corresponding to the basic drive torque is modeled in advance by experiments or the like. The target pinion angle calculation unit 112 calculates a basic drive torque by adding the basic assist component T _a1 ^* and the steering torque _Th , and calculates the target pinion angle θ _p ^* based on the obtained basic drive torque based on an ideal model. To do. Incidentally, the target pinion angle computation unit 112, when calculating a target pinion angle theta _p ^* is to the current value I _m, which is detected through the current sensor 116 provided on the feeding path with respect to the vehicle speed V and the assist motor 101,. This current value _Im is a value of an actual current supplied to the assist motor 101.

The pinion angle feedback control unit 113 takes in the target pinion angle θ _p ^* calculated by the target pinion angle calculation unit 112 and the actual pinion angle θ _p calculated by the pinion angle calculation unit 110, respectively. Pinion angle feedback control unit 113, so that the actual pinion angle theta _p follows the target pinion angle θ _p ^*, PID (proportional, integral, derivative) control is carried out as a feedback control of the pinion angle. That is, the pinion angle feedback control unit 113 obtains a deviation between the target pinion angle θ _p ^* and the actual pinion angle θ _p and obtains a correction component T _a2 ^* of the basic assist component T _a1 ^* so as to eliminate the deviation.

The adder 114 calculates the assist command value T _a ^* by adding the correction component T _a2 ^* to the basic assist component T _a1 ^* . The assist command value T _a ^* is a command value indicating a rotational force (assist torque) to be generated by the assist motor 101.

The energization control unit 115 supplies power corresponding to the assist command value T _a ^* to the reaction force motor 31. Specifically, the energization control unit 115 calculates a current command value for the assist motor 101 based on the assist command value _Ta ^* . Further, power supply controller 115 fetches the current value _{I m,} which is detected through the current sensor 57. The power supply controller 115 obtains the deviation of the actual current value I _m and the current command value, and controls the power supply to the assist motor 101 so as to eliminate the deviation. As a result, the assist motor 101 generates torque according to the assist command value _Ta ^* . Steering assistance according to the steering state is performed.

According to the EPS 100, the target pinion angle θ _p ^* is set from the basic drive torque T _in ^* based on the ideal model, and feedback control is performed so that the actual pinion angle θ _p matches the target pinion angle θ _p ^*. . As described above, there is a correlation between the pinion angle theta _p and the steered angle θt of the steered wheels 16, 16. For this reason, the steered operation of the steered wheels 16 and 16 according to the basic drive torque T _in ^* is also determined by the ideal model. That is, the steering feeling of the vehicle is determined by the ideal model. Therefore, a desired steering feeling can be realized by adjusting the ideal model.

Further, the actual turning angle θt is maintained at the turning angle θt corresponding to the target pinion angle θ _p ^* . For this reason, the effect of suppressing the reverse input vibration generated due to disturbances such as road surface conditions or braking can be obtained. That is, even when vibration is transmitted to the steering mechanism such as the steering shaft 12 via the steered wheels 16 and 16, the correction component T _a2 ^* is adjusted so that the pinion angle θ _p becomes the target pinion angle θ _p ^*. The For this reason, the actual turning angle θt is maintained at the turning angle θt corresponding to the target pinion angle θ _p ^* defined by the ideal model. As a result, the steering assist is performed in the direction to cancel the reverse input vibration, whereby the reverse input vibration is suppressed from being transmitted to the steering wheel 11.

However, the steering reaction force (responsiveness felt through the steering), which is a force (torque) acting in the direction opposite to the steering direction of the driver, only corresponds to the target pinion angle θ _p ^* . That is, for example, the steering reaction force does not change depending on the road surface state such as a dry road and a low friction road, so that it is difficult for the driver to grasp the road surface state as a response.

Therefore, in this example, the target pinion angle calculation unit 112 has the calculation function of the target rudder angle calculation unit 52 in the first embodiment.
The target pinion angle calculation unit 112 has a functional configuration similar to that of the target rudder angle calculation unit 52 shown in FIG. Whereas the previous target steering angle calculation unit 52 takes in the target steering reaction force T ₁ ^* , the target pinion angle calculation unit 112 in this example takes in the basic assist component T _a1 ^* . Further, current to capture the current value I _b of the current target steering angle computation section 52 of the previously supplied to the steering motor 41, the target pinion angle computation unit 112 of the present embodiment, is supplied to the assist motor 101 capturing the current value _{I m.} The target pinion angle calculation unit 112 takes in the steering torque _Th and the vehicle speed V in the same manner as the target steering angle calculation unit 52 described above. The target steering angle calculator 52 calculates the target steering angle θ ^* , whereas the target pinion angle calculator 112 of this example calculates the target pinion angle θ _p ^* . Only the part of the signal to be captured and the signal to be generated are different, and the content of the internal calculation processing of the target pinion angle calculation unit 112 is the same as that of the target steering angle calculation unit 52 described above.

Therefore, according to the present embodiment, the same effect as in the first embodiment can be obtained. That is, when a stopped state, a first spring reaction force torque _{T SP21} ^* absolute value based on the target pinion angle theta _p ^*, the second spring reaction force torque _T based on the current value _{I m} of the assist motor 101 _SP22 based on the difference between the absolute value of ^*, should be used which first spring reaction force torque _{T SP21} ^* and the second spring reaction force torque _{T SP22} ^* as a spring reaction force torque _{T sp2} ^* for when the vehicle is stopped is It is determined. For example, when the previous formula (B1) is satisfied, the second spring reaction force torque _{T SP22} ^* is used as the spring reaction force torque _{T sp2} ^* for when the vehicle is stopped based on the current value _{I m} of the assist motor 101. Thereby, since the steering reaction force according to the road surface condition (here, the low friction road) is obtained, the driver can easily grasp the road surface condition as a response.

<Other embodiments>
Note that the first and second embodiments may be modified as follows.
· In the second embodiment, the basic assist component calculation unit 111, but so as to obtain a basic assist component T _a1 ^* based on the steering torque T _h and the vehicle speed V, the basic assist on the basis of only the steering torque T _h The component T _a1 ^* may be obtained.

  In the second embodiment, the EPS (electric power steering device) 100 that applies the steering assist force to the pinion shaft 13 is taken as an example. However, for example, the steering assist force is applied to the steering shaft 12 or the steered shaft 14. It may be embodied in a type of electric power steering device.

In the first and second embodiments, the torque sensor 34 is provided on the steering shaft 12, but may be provided on the pinion shaft 13. If the steering torque T _h can be detected, setting locations of the torque sensor 34 is not limited.

In the first and second embodiments, when the vehicle is stopped, the second spring reaction force torque T _sp22 ^* calculated by the second vehicle reaction force model 92 is always used as the spring reaction force for stopping. You may use as torque _Tsp2 ^* . In this case, the first vehicle reaction force model 91, the distribution gain calculation unit 93, and the reaction force torque calculation unit 94 in the vehicle reaction force model 82 for stopping can be omitted.

DESCRIPTION OF SYMBOLS 11 ... Steering wheel, 13 ... Pinion shaft (rotary body) which comprises a steering mechanism, 14 ... Steering shaft which comprises a steering mechanism, 16 ... Steering wheel, 31 ... Reaction force motor (control object), 35 ... Vehicle Reaction force control unit constituting control device for vehicle, 41... Steering motor (control target), 44. Steering control unit constituting control device for vehicle, 51... Target steering reaction force calculation unit (first calculation unit) , 52 ... Target rudder angle calculation unit (second calculation unit), 54 ... Steering angle feedback control unit (third calculation unit), 101 ... Assist motor (control target), 104 ... Assist control unit (vehicle control device) , 111 ... basic assist component calculation unit (first calculation unit), 112 ... target pinion angle calculation unit (second calculation unit), 113 ... pinion angle feedback control unit (third calculation unit), I _b ... Current value of steering motor, I _m ... Current value of the assist motor, T * ^... steering reaction force command value, T 1 _* ^... target steering reaction force (the first component of the steering reaction force command value), T 2 _* ^... steering angle correction amount (the steering reaction force command value ), T _sp22 ^* ... Second spring reaction force torque (first reaction force component), T _sp21 ^* ... First spring reaction force torque (second reaction force component), T _a ^* ... assist command value, T _a1 ^* ... basic assist component (first component of assist command value), T _a2 ^* ... correction component (second component of assist command value), T _δ ^* ... difference value, _Th ... Steering torque, T _in ^* ... basic drive torque, θ ^* ... target rudder angle (target rotation angle), θ _p ... pinion angle (actual rotation angle).

Claims (5)

A vehicle control device that controls a motor, which is a generation source of driving force applied to a steering mechanism of a vehicle, based on a command value calculated according to a steering state,
A first calculation unit for calculating a first component of the command value according to at least a steering torque;
A second calculation unit that calculates a target rotation angle of a rotating body that rotates in conjunction with a turning operation of the steered wheels based on a basic drive torque that is a sum of the steering torque and the first component;
A third computing unit that computes a second component of the command value through feedback control that matches the actual rotational angle of the rotating body with the target rotational angle;
The second calculation unit reflects the reaction force component with respect to the basic drive torque, which is calculated based on the current value of the motor when the vehicle is in a stopped state, and then reflects the target drive angle on the basic drive torque. A vehicle control device for calculating The vehicle control device according to claim 1,
The second calculation unit calculates a second reaction force component with respect to the basic driving torque based on the target rotation angle, when the reaction force component based on the current value of the motor is a first reaction force component,
When the vehicle is in a stopped state, when the value of the second reaction force component is smaller than the value of the first reaction force component, the second reaction force component is reflected in the basic drive torque and then the target A vehicle control device that calculates a rotation angle. The vehicle control device according to claim 2,
The vehicle control device further increases the use ratio of the second reaction force component as the difference value between the first reaction force component and the second reaction force component increases. In the vehicle control device according to any one of claims 1 to 3,
The steering mechanism includes a pinion shaft as the rotating body that is mechanically separated from a steering wheel, and a steered shaft that steers steered wheels in conjunction with rotation of the pinion shaft,
As a control object, a reaction force motor that generates a steering reaction force that is a torque in a direction opposite to the steering direction as the driving force applied to the steering wheel based on the command value;
A steering motor that generates a turning force for turning the steered wheels provided to the pinion shaft or the steered shaft, and
The second calculation unit reflects the reaction force component with respect to the basic drive torque, which is calculated based on the current value of the steered motor when the vehicle is in a stopped state, on the basic drive torque, and then sets the target A vehicle control device that calculates a rotation angle. In the vehicle control device according to any one of claims 1 to 3,
The steered mechanism includes a pinion shaft as the rotating body interlocked with a steering wheel and a steered shaft that steers steered wheels in conjunction with rotation of the pinion shaft,
The vehicle control device, wherein the motor is an assist motor that generates a steering assist force that is a torque in the same direction as a steering direction as the driving force applied to the steering wheel.

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