JP5279182B2 - Vehicle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress control interference between "basic control of a control target by a certain control means" and "correction control to correct basic control by other control means". <P>SOLUTION: This device is provided with; a first control unit U1 which is equipped with a first control means A1 which has one or more first control sections A11-A1i determining basic control amount of a control target of a vehicle and determines the basic control amount based on the calculation result of the first control section; and a second control unit U2 which is independent from the first control unit, and equipped with a second control means A2 which has one or more second control sections A21-A2j determining the correction control amount of the control target to be used for correcting the basic control amount, and determines the correction control amount based on a calculation result of the second control section. When the basic control based on the basic control amount and the correction control based on the amount of corrected controls may interfere with each other, all or a part of the control functions of the first control section are stopped. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a vehicle control device.

In Patent Document 1 below, auxiliary steering torque generation control means (software) for generating auxiliary steering torque based on steering torque generated by the driver's steering, and steering reaction force against the turning behavior according to the turning behavior of the vehicle. There is disclosed a vehicle steering apparatus provided with a reaction force generation control means (software) for generating.
Japanese Patent Laid-Open No. 7-10023

  In this apparatus, the auxiliary steering torque generation control means and the reaction force generation control means are provided in separate control units (hardware) that are independent of each other, and a failure of the reaction force generation control means is detected. Thus, the generation of the steering reaction force by the reaction force generation control means is prohibited.

  That is, the system for achieving the steering torque control function is composed of a plurality of control means respectively provided in separate control units. Thereby, the robustness of the system is improved against a failure of a sensor or the like.

  By the way, consider a case where a system that achieves a control function for controlling a certain control object is composed of a plurality of control means (software). In this case, “the basic control of the control target by a certain control unit” and “the correction control for correcting the basic control by another control unit” may interfere with each other.

  For example, when the object to be controlled is the steering angle of the front wheels, to improve the steering stability of the front wheels based on the basic control for determining the front wheel steering angle from the rotation angle of the steering wheel and the vehicle body speed, etc., and to improve the running stability of the vehicle When the front wheel steering instruction direction is reversed based on the correction control for correcting the front wheel steering angle and performing the counter steering operation or the like, the basic control and the correction control interfere with each other.

  Hereinafter, in this specification, a change (instruction) direction of a control object based on a certain control and a change (instruction) direction of the control object based on another control are referred to as “control interference”. An object of the present invention is to provide a vehicle control device capable of suppressing the occurrence of such control interference.

A vehicle control device according to the present invention includes one or more first control units (software) that perform calculations for determining a basic control amount of a control target of the vehicle based on the state of the vehicle. A first control unit (hardware) comprising first control means (software) for determining the basic control amount based on the calculation results of the one or more first control units;
One or a plurality of second control units (software) for performing calculation for determining the correction control amount of the control object used for correction of the basic control amount based on the state of the vehicle A second control unit (hardware) independent of the first control unit, comprising second control means (software) for determining the correction control amount based on the calculation results of one or a plurality of second control units. )When,
Control target control means (software, (hardware)) for controlling the control target based on the target control amount of the control target obtained by correcting the basic control amount by the correction control amount;
Determination means (software) for determining whether or not the control target is in an operating state of the second control means that is in a state of being corrected using the correction control amount;
When it is determined that the second control means is in an operating state, a control stop means (software) that keeps all the calculation results of the one or more first control sections constant or gradually returns to zero. ) And.

  Here, the control target control means is preferably provided in the first control unit, the determination means is preferably provided in the second control unit, and the control stop means is the first control unit. It is preferably provided in the control unit.

  The control objects include, for example, front wheel steering angle, rear wheel steering angle, steering wheel steering torque, and the like. Hereinafter, holding a calculation result of a certain control unit constant or returning it gradually toward zero is referred to as “stop” (control function) of the control unit.

  According to the above configuration, when it is determined that the operating state of the second control means, that is, control of the control target by the first control means (basic control) and control of the control target by the second control means (correction control). All of the first control units related to the basic control are stopped. That is, the basic control function is completely stopped. Therefore, the occurrence of control interference between the basic control and the correction control can be suppressed. Further, the correction control function of the control target can be continuously secured. In the present invention, it is assumed that there is a combination that may cause control interference between the plurality of first control units related to basic control and the plurality of second control units related to correction control. .

  Here, the determination means, for example, from the time when the correction control amount changes from zero to a value outside the predetermined range including zero, a period during which the correction control amount is maintained within the predetermined range reaches a predetermined period. Until this point, it can be configured to determine that the second control means is in an operating state.

  As a result, when the correction control amount becomes transiently a value within the minute range only for a very short period (for example, when the correction control amount changes across “0”), the “operation of the second control means” It can continue to be determined as “state”. In other words, from the state determined as the “operating state of the second control means”, it is once determined that it is not the “operating state of the second control means”, and again after a very short period, the “operating state of the second control means” is set again. A situation in which the determination result is unnecessarily reversed at short time intervals as determined can be prevented. As a result, the occurrence of control interference between the basic control and the correction control can be appropriately suppressed.

  Alternatively, the determination unit may be configured to determine that the second control unit is in an operating state when the correction control amount is outside a predetermined range including zero. That is, when the correction control amount is within the minute range, it is always determined that the operation state of the second control means is not established. However, in this case, as described above, in a case where the correction control amount is transiently a value within the minute range only for an extremely short period, a situation in which the determination result is unnecessarily reversed at a short time interval may occur. As a result, there may occur a case where the generation of control interference between the basic control and the correction control cannot be appropriately suppressed. Hereinafter, from the time when the calculation result of a certain control unit changes from zero to a value outside the predetermined range including zero to the time point when the calculation result of the control unit is maintained within the predetermined range reaches the predetermined period. In the meantime, or when the calculation result is out of a predetermined range including zero, it is referred to as an “operation state” of the control unit.

  Further, when there are a plurality of the first control units, the control stop unit is a part of the plurality of first control units when it is determined that the second control unit is in an operating state. The direction of change of the control object based on the calculation result is stopped at least one of the control object correction directions based on any one of the calculation results of the one or more second control units. It may be configured to.

  According to this, when the control interference can occur between the basic control and the correction control, only the one that can interfere with any of the second control units among the plurality of first control units related to the basic control is stopped. . In other words, a plurality of first control units related to basic control that do not interfere with any of the second control units do not stop. Therefore, it is possible to suppress the occurrence of control interference between the basic control and the correction control while ensuring a certain degree of the basic control function to be controlled.

  By the way, there may be a case where only some of the plurality of second control units related to the correction control can interfere with control of any of the first control units. In this case, the determination unit is a part of the plurality of second control units, and the correction direction of the control target based on the calculation result is any of the calculation results of the one or more first control units. At least one of the calculation results of the control object based on whether the control object may change in the opposite direction changes from zero to a value outside the predetermined range including zero, and at least one of the calculation results is within the predetermined range. Until the time when the period maintained at a predetermined period is reached, or when at least one of the calculation results is outside a predetermined range including zero, it is determined that the second control means is in an operating state. It may be configured.

  According to this, when at least one of the plurality of second control units related to the correction control that can interfere with the control of any of the first control units is in the operating state, it is determined as “the operating state of the second control means”. The In other words, even if one of the plurality of second control units related to the correction control that cannot interfere with any of the first control units is in an operating state, all or part of the first control unit is not stopped. That is, it is possible to prevent a situation in which the basic control function to be controlled is unnecessarily stopped or restricted.

  In addition, when there are a plurality of both the first control unit and the second control unit, the determination unit uses the operation state of the second control unit (that is, the control target uses the calculation result of the second control unit). The second control unit independently determines whether or not the control stop means is based on the determination result of the determination means. Calculation of the second control unit that is a part of the plurality of first control units or a part of the plurality of first control units and in which the change direction of the control object based on the calculation result is determined as the operating state The calculation result of at least one of those that can be opposite to the correction direction of the control target based on the result may be held constant, or may be gradually returned toward zero.

  According to this, depending on which one of the plurality of second control units related to the correction control is in the operating state, the first control unit that can interfere with the control of the second control unit in the same operating state, Selectively stopped. Accordingly, as described above, it is possible to prevent a situation in which the basic control function to be controlled is stopped and restricted unnecessarily. In addition, the first control unit to be stopped can be selected according to the degree of control interference with the second control unit in the operating state. Therefore, the situation where the basic control function to be controlled is stopped and restricted unnecessarily can be prevented more reliably.

  Embodiments of a vehicle control device according to the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram of this embodiment. As shown in FIG. 1, this embodiment is a first control unit U1 (an ECU that performs drive control of an actuator (ACT) 1 that controls a certain control target (first control target, for example, a front wheel steering angle). Hardware) and a second control unit U2 (hardware) that is an ECU that performs drive control of an actuator (ACT) 3 that controls another control target (second control target, for example, braking / driving force of a wheel) It has. The first control unit U1 and the second control unit U2 are separate and independent ECUs that are communicably connected to each other via a communication bus.

  The first control unit U1 calculates the basic control amount used for the first control (basic control) of the first control object based on the (running) state of the vehicle obtained from various sensor signals, communication signals, and the like. The correction control amount used for the control means A1 (software) and the second control (correction control) for correcting the basic control transmitted from the second control unit U2 and the basic control amount are added (superimposed). Addition means B1 (software) for calculating the first target control amount, actuator drive processing unit C1 (software) for sending a drive signal to ACT1 based on the first target control amount, and ACT1 operates normally Normal operation monitoring means D1 (software) for monitoring whether or not the control is performed, and control stop means E1 (software) described later.

  The first control means A1 is an i (i: natural number) first control unit (first control element, first control mode) (the eleventh control unit A11, the first control mode) that performs an operation for calculating the basic control amount. 12 control unit A12,..., 1i control unit A1i) (software), and control amount calculation unit A1T (software) of the first control unit that calculates the control amount (= basic control amount) of the first control unit A1 Wear).

  The second control unit U2 calculates the second target control amount A3 (for calculating the second control target based on the (traveling) state of the vehicle obtained from various sensor signals, communication signals, and the like. Software) and an actuator drive processing unit B3 (software) for sending a drive signal to the ACT 3 based on the second target control amount.

  The third control means A3 is a k (k: natural number) third control unit (31st control unit A31,..., 3k control unit A3k) that performs an operation for calculating the second target control amount. (Software) and a control amount calculation unit A3T (software) of third control means for calculating a control amount (= second target control amount) of the third control means A3.

  The second control unit U2 further includes second control means A2 (software) that calculates the correction control amount based on the (traveling) state of the vehicle obtained from various sensor signals, communication signals, and the like. The second control means A2 performs j (j: natural number) second control units (second control element, second control mode) (the twenty-first control unit A21, the second control mode) that perform the calculation for calculating the corrected control amount. 22 control unit A22,..., 2j control unit A2j) (software) and control amount calculation unit A2T (software) of the second control means for calculating the control amount (= corrected control amount) of the second control means A2. Wear). Here, the control amount of the first control means A1 (= basic control amount) and the control amount of the second control means A2 (= correction control amount) are the same as the first control object (ACT1) to be controlled. Dimensional physical quantity. The control amount calculation unit A2T transmits this corrected control amount to the adding means B1 in the first control unit U1, and transmits a control flag to be described later to the control stop means E1 in the first control unit U1.

  Thus, the basic control based on the basic control amount and the correction control based on the correction control amount are the same first control target (ACT1). The basic control is normal (constant) control of the first control target (ACT1). The correction control is, for example, temporary control that corrects the basic control by correcting the basic control amount with the correction control amount only when stabilization in the yaw motion of the traveling vehicle is necessary. That is, the correction control amount is normally “0”, and is a value other than “0” only when, for example, stabilization in the yaw motion of the traveling vehicle is required.

  Here, the eleventh control unit A11 among the i first control units in the first control unit A1 related to the basic control and the j second control units in the second control unit A2 related to the correction control. It is assumed that the “control interference” described above can occur with the 21st control unit A21. In this case, “control interference” refers to the change (instruction) direction of the first control target (ACT1) based on the calculation result of the eleventh control unit A11 and the first control target (based on the calculation result of the twenty-first control unit A21). It means a phenomenon in which the correction (instruction) direction of ACT1) (change (instruction) direction of the first controlled object (ACT1) to be corrected) is reversed.

  Hereinafter, for convenience of explanation, a period during which the correction control amount is continuously maintained within the minute range from the time when the correction control amount changes from “0” to a value outside the predetermined minute range including “0” is predetermined. The period up to the point in time when the period is reached or the period in which the correction control amount is outside the minute range is referred to as the “operation state” of the second control means. Similarly, the calculation result of the control unit from the time when the calculation result of a certain control unit in the j second control units A21 to A2j changes from “0” to a value outside a predetermined minute range including “0”. Is a period until the time when the period continuously maintained within the minute range reaches a predetermined period, or a period when the calculation result of the control unit is outside the minute range is the `` operation state '' of the control unit Called. Furthermore, the calculation result of a certain control unit in the i first control units A11 to A1i is held constant or gradually returned to “0”. This is referred to as “stop”.

  In this embodiment, the occurrence of control interference is suppressed using any one of the following six patterns. Hereinafter, it will be described in order.

<Pattern 1>
The control flag is set to “1” when the second control means is in the “operating state”, and is set to “0” when the second control means is not in the “operating state”. When the control flag is “1”, the control stop means E1 to which the value of the control flag is transmitted “stops” all of the first control units A11 to A1i. That is, in the pattern 1, when the second control unit is in the “operating state”, all of the first control units are “stopped”, and the basic control function of the first control target is completely “stopped”. This suppresses the occurrence of control interference between the basic control and the correction control of the first control target (more specifically, control interference between the eleventh control unit A11 and the twenty-first control unit A21). Is done. Note that the correction control function of the first control target can be continuously secured.

<Pattern 2>
As in the case of pattern 1, the control flag is set to “1” when the second control unit is in the “operating state”, and is set to “0” when the second control unit is not in the “operating state”. When the control flag is “1”, the control stopping unit E1 “stops” only the eleventh control unit A11 that may generate control interference with the twenty-first control unit A21 among the first control units A11 to A1i. . That is, in the pattern 2, when the second control unit is in the “operating state”, only the portion of the first control unit that may generate control interference with any of the second control units is “stopped”.

  In other words, the first control unit that does not interfere with any of the second control units is not “stopped”. Therefore, the occurrence of control interference between the basic control of the first control target and the correction control is suppressed while securing the basic control function of the first control target to some extent.

<Pattern 3>
When at least one of the second control units A21 to A2j that can interfere with control of any of the first control units (21st control unit A21 in this example) is in the “operating state”, the second control flag If the control means is in the “operating state”, it is set to “1”, and if the 21st control unit A21 is not in the “operating state”, the second control means is set to “0”, assuming that it is not in the “operating state”. Is done. When the control flag is “1”, the control stop unit E1 “stops” all of the first control units A11 to A1i as in the case of the pattern 1.

  That is, in the pattern 3, when at least one of the second control units A21 to A2j that can interfere with the control of any of the first control units is in the “operating state”, all of the first control units are “stopped”. The basic control function of the first control object is completely “stopped”. Thereby, generation | occurrence | production of the control interference between the basic control of 1st control object and correction control is suppressed. In addition, one of the second control units A21 to A2j that cannot interfere with any of the first control units (in this example, the 22nd control unit A22,..., The 2j control unit A2j) ", The entire first control unit is not" stopped ". That is, it is possible to prevent a situation where the basic control function of the first control target is unnecessarily stopped or restricted.

<Pattern 4>
As in the case of pattern 3, at least one of the control flags that can interfere with any of the first control units among the second control units A21 to A2j (21st control unit A21 in this example) is in the “operating state”. In some cases, it is set to “1”, and is set to “0” when the 21st control unit A21 is not in the “operating state”. When the control flag is “1”, the control stop means E1 is only the eleventh control unit A11 that can generate control interference with the twenty-first control unit A21 among the first control units A11 to A1i, as in the pattern 2. “Stop”.

  Therefore, in the pattern 4, the effects of the pattern 2 and the pattern 3 can be exhibited. That is, the occurrence of control interference between the basic control of the first control target and the correction control can be suppressed while securing the basic control function of the first control target to some extent, and the basic control of the first control target is controlled. The situation where the function is unnecessarily stopped or restricted can be prevented.

<Pattern 5>
The control flag is provided for each of the second control units A21 to A2j. For each control unit, the control flag corresponding to when the control unit is in the “operating state” is set to “1”, and the control unit is set to “activate”. When it is not in “state”, it is set to “0”. The control stop means E1 “stops” all the first control units A11 to A1i based on the values of the j control flags. In this case, for example, the control flag corresponding to at least one of the second control units A21 to A2j that can interfere with any one of the first control units (the 21st control unit A21 in this example) is “1”. In this case, all of the first control units A11 to A1i are “stopped”. Thereby, the same effect as the pattern 3 can be exhibited.

<Pattern 6>
Similarly to the pattern 5, the control flag is set for each of the second control units A21 to A2j. Based on the values of the j control flags, the control stop means E1 selectively selects one of the first control units A11 to A1i that can interfere with the control of the second control unit that is determined to be in the “operating state”. Stop. In this case, for example, when the control flag corresponding to the twenty-first control unit A21 is “1”, only the eleventh control unit A11 that may generate control interference with the twenty-first control unit A21 is “stopped”. Thereby, the effect similar to the pattern 4 can be exhibited. In addition, the first control unit to be stopped can be selected according to the degree of control interference with the second control unit in the “operating state”. Therefore, the situation where the basic control function of the first control target is unnecessarily stopped and restricted can be prevented more reliably.

  In addition, as a period corresponding to the “operation state” of the second control means or the second control unit, “the period during which the corrected control amount or the calculation result of the control unit is outside the minute range” is used. The correction control amount or the calculation result of the control unit continues within the minute range from the time when the correction control amount or the calculation result of the control unit changes from “0” to a value outside a predetermined minute range including “0”. It is preferable to use the “period until the time when the maintained period reaches the predetermined period”.

  As a result, the second control means when the corrected control amount or the calculation result of the control unit becomes a value within the minute range transiently for a very short period of time (for example, when changing across “0”). Alternatively, it can continue to be determined as the “operating state” of the control unit. In other words, the determination result is unnecessary in a short time interval such that it is once determined that it is not the “operation state” from the state determined as the “operation state”, and is again determined as the “operation state” after the extremely short period. Can be prevented from reversing. As a result, the occurrence of control interference between the basic control and the correction control can be appropriately suppressed.

  The embodiment of the vehicle control apparatus according to the present invention has been described above. Next, each example of the vehicle control apparatus according to the present invention, which is a specific example of this embodiment, will be described with reference to the drawings.

(First embodiment)
FIG. 2 shows a schematic configuration of a vehicle equipped with a control device (hereinafter referred to as “this device”) according to a first embodiment of the present invention. The present apparatus includes a front wheel steering control mechanism 20, a rear wheel steering control mechanism 30, and a hydraulic unit 40.

  In the front wheel steering control mechanism 20, a steering wheel 21 operated by a driver is connected to an electric power steering mechanism (EPS) via an upper steering shaft 22, a steering gear ratio variable mechanism VGRS (STRf), and a lower steering shaft 23. ing. Thereby, the rotation of the steering wheel 21 is transmitted to the EPS.

  The EPS is constituted by one of well-known configurations, and converts the rotational motion of the lower steering shaft 23 into the translational motion of the rod 24 in the left-right direction of the vehicle body and in a direction to assist the rotational torque received from the lower steering shaft 23. An assist force for driving the rod 24 is generated by the motor MTe. As described above, when the steering wheel 21 is rotated by the driver, the front wheels FL and FR are steered while the driver's steering torque is assisted by the assist force.

  The STRf is composed of a motor MTf and a gear mechanism (not shown). By controlling the (absolute) rotation angle of the motor MTf, the relative rotation angle of the lower steering shaft 23 with respect to the upper steering shaft 22 (hereinafter, simply referred to as STRf). It is also called “relative angle”). Thereby, by controlling the relative angle, the ratio of the rotation angle of the steering wheel 21 to the steering angle of the front wheels FL and FR (steering gear ratio) can be changed.

  The rear wheel steering control mechanism 30 has a rear wheel steering mechanism STRr. The STRr includes a motor MTr and a gear mechanism (not shown), and the position of the rod 31 in the left-right direction of the vehicle body can be adjusted by controlling the (absolute) rotation angle of the motor MTr. Thus, the steering angle of the rear wheels RL and RR can be changed by controlling the rotation angle of the motor MTr.

  The hydraulic unit (HU) 40 has a known configuration including a plurality of solenoid valves, a hydraulic pump, a motor, and the like. The HU 40 supplies the brake fluid pressure corresponding to the operation of the brake pedal BP by the driver to the wheel cylinders W ** at the time of non-control, and independently of the operation of the brake pedal BP at the time of control. The brake fluid pressure in the wheel cylinder W ** can be adjusted for each wheel.

In addition, “**” added to the end of various symbols, etc., indicates “fl”, “fr” added to the end of the various symbols, etc. to indicate which wheel the various symbols, etc. relate to. "Fl" indicates the left front wheel, "fr" indicates the right front wheel, "rl" indicates the left rear wheel, and "rr" indicates the right rear wheel. For example, the wheel cylinder W ** is the left front wheel wheel cylinder Wfl,
A right front wheel wheel cylinder Wfr, a left rear wheel wheel cylinder Wrl, and a right rear wheel wheel cylinder Wrr are comprehensively shown.

  This apparatus includes a wheel speed sensor 51 ** that detects a wheel speed Vw **, a steering wheel rotation angle sensor 52 that detects a rotation angle θsw (from a neutral position) of the steering wheel 21, and a driver's steering wheel 21. A steering torque sensor 53 for detecting the steering torque Tsw of the vehicle body, a yaw rate sensor 54 for detecting the yaw rate Yr of the vehicle body, a longitudinal acceleration sensor 55 for detecting the longitudinal acceleration Gx in the longitudinal direction of the vehicle body, and a lateral acceleration Gy in the lateral direction of the vehicle body. A lateral acceleration sensor 56 that detects the actual steering angle (actual front wheel steering angle δfa) of the front wheels FL and FR, and the actual steering angle (actual rear wheel steering angle δra) of the rear wheels RL and RR. ), A wheel cylinder pressure sensor 59 ** for detecting a wheel cylinder pressure Pw **, and an electronic control unit (ECU) 60.

  The ECU 60 is a microcomputer composed of a plurality of independent ECUs (ECUs 0 to 4) connected to each other via a communication bus CB. The ECU 60 is electrically connected to the HU 40 and the sensors 51 to 59. The ECUs 0 to 4 in the ECU 60 execute dedicated controls.

  Specifically, the ECU 0 detects slip suppression control (control / control) such as known anti-skid control (ABS control) and traction control (TCS control) based on signals from the wheel speed sensor 51 **, the longitudinal acceleration sensor 55, and the like. It is a braking / driving force control unit that executes (driving force control). The ECU 1 is a front wheel steering angle control unit that executes front wheel steering angle control based on signals from the steering wheel rotation angle sensor 52, the wheel speed sensor 51 **, and the like. The ECU 2 is a rear wheel steering angle control unit that executes rear wheel steering angle control based on signals from the front wheel steering angle sensor 57, the wheel speed sensor 51 **, and the like. The ECU 3 is a power steering control unit that executes well-known electric power steering control based on a signal from the steering torque sensor 53. The ECU 4 is a powertrain system control unit that executes control of a powertrain system such as an engine (not shown) and an automatic transmission.

  In the first embodiment, the front wheel steering angle control unit ECU1 corresponds to the first control unit U1 in FIG. 1, and the braking / driving force control unit ECU0 corresponds to the second control unit U2 in FIG. Hereinafter, the front wheel steering angle control unit ECU1 and the braking / driving force control unit ECU0 will be described.

<Front Wheel Steering Angle Control Unit ECU1>
FIG. 3 is a functional block diagram of the front wheel steering angle control unit ECU1. 3, functional blocks that exhibit the same functions as the functional blocks in FIG. 1 are given the same reference numerals as those in FIG. 1 (the same applies to other drawings).

  As shown in FIG. 3, the control object (the first control object) of the front wheel steering angle control unit ECU1 is the front wheel steering angle δf, and the motor MTf (see FIG. 2) corresponds to ACT1 in FIG. The front wheel steering angle control means A1 corresponds to the first control means A1 in FIG. 1, and the front wheel steering angle control means A1 corresponds to the front wheel steering ratio control part A11 and differential steer control corresponding to the first control parts A11 to A1i in FIG. And a front wheel basic steering angle target value calculation unit A1T corresponding to the control amount calculation unit A1T of the first control means of FIG.

  The front wheel steering ratio control unit A11 rotates the steering wheel 21 with respect to the front wheel steering angle based on the vehicle speed Vx calculated from the wheel speed Vw ** based on one of well-known formulas and the table shown in FIG. A front wheel steering ratio SGf which is an angle ratio is obtained. As a result, when the vehicle body speed Vx is small, the front wheel steering ratio SGf is set to a small value (quick) to improve the handling of the vehicle. When the vehicle body speed Vx is large, the front wheel steering ratio SGf is set to a large value (slow). This improves the steering stability of the vehicle.

  The differential steer control unit A12 is for improving the yaw response of the vehicle, and obtains the differential steer angle θswb based on the time differential value dθsw of the rotation angle θsw of the steering wheel and the table shown in FIG.

  The front wheel basic steering angle target value calculation unit A1T calculates a front wheel basic steering angle target value δft corresponding to the basic control amount according to the following equations (1) to (3).

δfgt = θsw / SGf (1)
δfbt = θswb / SGf (2)
δft = δfgt + δfbt (3)

  The adding means B1 adds (superimposes) the front wheel basic steering angle target value δft and the front wheel corrected steering angle target value δfc corresponding to the correction control amount transmitted from the braking / driving force control unit ECU0. A front wheel steering angle target value (δft + δfc) corresponding to one target control amount is obtained.

  The electric motor drive processing unit C1 sends a drive signal to the motor MTf based on the front wheel steering angle target value (δft + δfc). Accordingly, the front wheel steering angle δf is controlled based on the front wheel steering angle target value (δft + δfc).

  The normal operation monitoring means D1 monitors whether the front wheel steering angle target value (δft + δfc) or the time change rate (change gradient) of the actual front wheel steering angle δfa is larger than a predetermined normal determination reference value. When the steering angle target value (δft + δfc) or the time change rate (change gradient) of the actual front wheel steering angle δfa is smaller than the normal determination reference value, the normal operation determination of the front wheel steering angle control unit ECU1 is performed. When larger than the normal determination reference value, the abnormality determination of the front wheel steering angle control unit ECU1 is performed.

<Braking / braking force control unit ECU0>
FIG. 6 is a functional block diagram of the braking / driving force control unit ECU0. As shown in FIG. 6, the control target (the second control target) of the braking / driving force control unit ECU0 is the braking / driving force, the HU 40 (see FIG. 2), and the driving force actuator (for example, for driving the throttle valve). A motor or the like (not shown) corresponds to ACT3 in FIG. The braking / driving force control means A3 corresponds to the third control means A3 in FIG. 1, and the braking / driving force control means A3 corresponds to the anti-skid control part A31 and the traction control part A32 corresponding to the third control parts A31 to A3k in FIG. And a vehicle stability control unit A33 and a braking / driving force target value calculation unit A3T corresponding to the control amount calculation unit A3T of the third control means of FIG. The braking / driving force target value calculation unit A3T calculates a braking / driving force target value corresponding to the second target control amount. Actuator drive processing units B31 and B32 correspond to the actuator drive processing unit B3 of FIG. 1, and send drive signals to the HU 40 and the drive force actuator based on the braking / driving force target values, respectively.

  The braking / driving force control unit ECU0 further includes front wheel correction steering angle control means A2 corresponding to the second control means A2 of FIG. The front wheel correction steering angle control means A2 outputs a front wheel correction steering angle target value δfc based on a value representing the movement state of the vehicle in the yaw direction in order to improve the stability in the movement of the vehicle in the yaw direction. Here, the “value representing the motion state in the yaw direction” is a motion state amount deviation representing the degree of understeer and oversteer, which will be described later, and the braking force difference between the left and right wheels that causes the motion in the yaw direction of the vehicle. It is a driving force difference. The front wheel correction steering angle control means A2 includes an understeer control unit A21, an oversteer control unit A22, a braking μ split control unit A23, and a driving μ split control unit A24 corresponding to the second control units A21 to A2j of FIG. And a front wheel correction steering angle target value calculation unit A2T corresponding to the control amount calculation unit A2T of the second control means of FIG.

  The understeer control unit A21 changes the front wheel steering ratio to a larger value in order to suppress an increase in the front wheel steering angle δf (accordingly, an increase in the front wheel slip angle) during understeering. The oversteer control unit A22 automatically adjusts the front wheel steering angle so as to reduce the inward turning yaw moment or to increase the outward turning yaw moment during oversteering.

  The braking μ-split control unit A23 automatically adjusts the front wheel steering angle so as to cancel the yaw moment generated by the difference in braking force between the left and right wheels. The driving μ-split control unit A24 automatically adjusts the front wheel steering angle so as to cancel the yaw moment generated by the difference in driving force between the left and right wheels.

  More specifically, as illustrated in FIG. 7, the understeer control unit A21 and the oversteer control unit A22 include the target motion state amount Vmt calculated by the target motion state amount calculation unit A211 and the actual motion state amount calculation unit. By comparing the actual movement state quantity Vma calculated in A212 with the comparison means A213, movement state quantity deviations ΔVm_us and ΔVm_os representing the degree of understeer and oversteer are obtained. Here, the “motion state amount” is a value calculated using at least one of the yaw rate, the lateral acceleration, the vehicle body slip angle, and the vehicle body slip angular velocity of the vehicle. The “target motion state quantity Vmt” is calculated using the steering wheel rotation angle θsw, the vehicle body speed Vx, etc., and the “actual motion state quantity Vma” is calculated using the yaw rate Yr, the lateral acceleration Gy, the vehicle body speed Vx, etc. Is done.

  The braking μ-split control unit A23 obtains a braking force difference ΔBf between the left and right wheels from the braking force Bf ** calculated by the braking force calculation unit A231. The driving μ-split control unit A24 determines the driving force difference ΔDf between the left and right wheels from the driving force Df ** calculated by the driving force calculating unit A241.

  The front wheel corrected steering angle target value calculation unit A2T calculates a front wheel corrected steering angle target value δfc corresponding to the correction control amount based on the motion state amount deviations ΔVm_us, ΔVm_os, the braking force difference ΔBf, and the driving force difference ΔDf. . As a result, the front wheel corrected steering angle target value δfc is normally “0”, and when it is necessary to suppress understeer and oversteer, vehicle deflection due to yaw moment based on the braking / driving force difference between the left and right wheels is suppressed. The value is not “0” only when the vehicle needs to be stabilized in the yaw motion, such as when it is necessary to do so.

  The front wheel corrected steering angle target value calculation unit A2T transmits the front wheel corrected steering angle target value δfc to the adding means B1 in the front wheel steering angle control unit ECU1, and the control stop means in the front wheel steering angle control unit ECU1. Send to E1. As described above, the basic control based on the front wheel basic steering angle target value δft and the correction control based on the front wheel corrected steering angle target value δfc are the same front wheel steering angle δf (MTf).

<Combination in which control interference occurs in the first embodiment>
The front wheel steering ratio control unit A11 of the two first control units in the front wheel steering angle control unit A1 related to the basic control, and the four second control units A21 to A21 in the front wheel correction steering angle control unit A2 related to the correction control. The “control interference” described above may occur between each of A24. “Control interference” in this case is based on the change (instruction) direction of the front wheel steering angle δf (MTf) based on the calculation result of the front wheel steering ratio control unit A11 and the calculation results of the second control units A21 to A24. It means a phenomenon in which the correction (instruction) direction of the front wheel steering angle δf (MTf) (change (instruction) direction of the corrected front wheel steering angle δf (MTf)) is reversed. Hereinafter, each control interference will be specifically described in order.

<< Front Wheel Steering Ratio Control Unit A11-Under Steer Control Unit A21 >>
When the vehicle is turning and decelerating, the front wheel steering ratio control unit A11 reduces the front wheel steering ratio SGf (makes it quicker). This means that when the steering wheel 21 is held, the front wheels are instructed to turn in the turning inner direction. On the other hand, the understeer control unit A21 increases the front wheel steering ratio SGf in order to suppress an increase in the front wheel steering angle δf. This means that when the steering wheel 21 is steered, the front wheels are instructed to steer in the direction of the turning outer side (the direction returning to the neutral position). As a result, the control interference occurs. As described above, when the understeer control unit A21 is in the “operating state”, the front wheel steering ratio control unit A11 is “stopped”, the front wheel steering ratio SGf is fixed, and the turning of the front wheels in the turning inner direction is suppressed. It is preferable.

<< Front Wheel Steering Ratio Control Unit A11-Oversteer Control Unit A22 >>
At the time of turning deceleration of the vehicle, as described above, the front wheel steering ratio control unit A11 reduces the front wheel steering ratio SGf (to make it quicker). This means that when the steering wheel 21 is held, the front wheels are instructed to turn in the turning inner direction. On the other hand, the oversteer control unit A22 instructs to steer the front wheels in the neutral position and further toward the outside of the turn in order to decrease the inward turning yaw moment or increase the outward turning yaw moment. . As a result, the control interference occurs. As described above, when the oversteer control unit A22 is in the “operating state”, the front wheel steering ratio control unit A11 is “stopped”, the front wheel steering ratio SGf is fixed, and the steering of the front wheels toward the turning inner side is suppressed. It is preferable to do.

<< Front Wheel Steering Ratio Control Unit A11-braking μ Split Control Unit A23 >>
μ When driving on a split road surface (road surfaces with different left and right road surface friction coefficients) (during turning μ split road surface), if the high road surface friction coefficient side corresponds to the inside of the turn, The power difference generates a turning inward moment. In order to cancel this, the braking μ-split control unit A23 instructs the front wheels to turn toward the neutral position and further toward the outside of the turn. On the other hand, the front wheel steering ratio control unit A11 reduces the front wheel steering ratio SGf (to make it quicker) by decelerating the vehicle. That is, when the steering wheel 21 is held, the front wheel steering ratio control unit A11 instructs the front wheels to turn in the turning inner direction. As a result, the control interference occurs. As described above, when the braking μ-split control unit A23 is in the “actuated state”, the front wheel steering ratio control unit A11 is “stopped”, the front wheel steering ratio SGf is fixed, and the front wheels are steered in the turning inner direction. Is preferably suppressed.

<< Front Wheel Steering Ratio Control Unit A11-Driving μ Split Control Unit A24 >>
In the “turning μ-split road surface travel”, when the high road surface friction coefficient side corresponds to the inside of the turn, the driving force difference between the left and right wheels generates a moment in the turning direction. In order to cancel this, the driving μ-split control unit A24 instructs the front wheels to turn inward. On the other hand, the front wheel steering ratio control unit A11 increases (slowers) the front wheel steering ratio SGf by acceleration of the vehicle. That is, when the steering wheel 21 is held, the front wheel steering ratio control unit A11 instructs the front wheels to turn outward in the turning direction (the direction returning to the neutral position). As a result, the control interference occurs. In this way, when the driving μ-split control unit A24 is in the “operating state”, the front wheel steering ratio control unit A11 is “stopped”, the front wheel steering ratio SGf is fixed, and the front wheels are steered in the direction of turning outward. Is preferably suppressed.

<Process for suppressing control interference in the first embodiment>
In the first embodiment, for example, control interference can be suppressed by performing the following processing.
1. The control flag is set to “1” when the front wheel correction steering angle control means A2 is in the “operating state”, and is set to “0” when the front wheel correction steering angle control means A2 is not in the “operating state”. When the control flag is “1”, the control stop means E1 in the front wheel steering angle control unit ECU1 “stops” only the front wheel steering ratio control unit A11 that can interfere with any of the second control units A21 to A24. (Corresponding to the above pattern 2). The correction control function of the front wheel correction steering angle control means A2 and the control function of the differential steer control unit A12 can be secured continuously.
2. The control flag has the above 1. Is set in the same manner as Here, in the front wheel steering angle control, the front wheel steering ratio control unit A11 is a main part of the first control unit. For this reason, the above 1. When the control flag is “1”, all the first control units (specifically, the front wheel steering ratio control unit A11 and the differential steer control unit A12) may be “stopped” (corresponding to the above pattern 1). ).
3. The control flag is provided for each of the second control units A21 to A24. For each control unit, the control flag corresponding to when the control unit is in the “operating state” is set to “1”, and the control unit is set to “activate”. When it is not in “state”, it is set to “0”. The control stop means E1 “stops” all of the first controllers A11 and A12 based on the values of the four control flags (corresponding to the above pattern 5). In this case, for example, when the control flag corresponding to at least one of the second controllers A21 to A24 that can interfere with the front wheel steering ratio controller A11 is “1”, all of the first controllers A11 and A12 are “Stopped”.
4). The control flag is the same as in 3. above. Is set in the same manner as Based on the values of the four control flags, the control stop means E1 selectively selects one of the first control units A11 and A12 that can interfere with the control of the second control unit that is determined to be in the “operating state”. "Stop" (corresponding to the above pattern 6). In this case, for example, when the control flag corresponding to at least one of the second controllers A21 to A24 that can interfere with the front wheel steering ratio controller A11 is "1", the front wheel steering ratio controller A11 is "stopped". Is done.

  As described above, after the completion of the “processing for suppressing control interference” described above, the front wheel basic steering angle target value δft is gradually (predetermined to a value calculated by the front wheel basic steering angle target value calculation unit A1T). (With speed)

  The above 1. When the control flag set in the same manner as “1” is “1”, the control stop means E1 may “stop” the normal operation monitoring means D1. In addition, the above 3. When at least one of the four control flags set in the same manner as “1” is “1”, the control stop unit E1 may “stop” the normal operation monitoring unit D1. As a result, the front wheel steering angle target value (δft + δfc) obtained by abruptly superimposing the front wheel corrected steering angle target value δfc on the front wheel basic steering angle target value δft, or the time change rate (change gradient) of the actual front wheel steering angle δfa As a result of this rapid increase, it is possible to suppress a situation in which an erroneous determination that the front wheel steering angle control unit ECU1 is normal is abnormal although it is normal.

(Second embodiment)
Next, a control device according to a second embodiment of the present invention will be described. In the second embodiment, the rear wheel steering angle control unit ECU2 corresponds to the first control unit U1 in FIG. 1, and the braking / driving force control unit ECU0 corresponds to the second control unit U2 in FIG. Hereinafter, the rear wheel steering angle control unit ECU2 and the braking / driving force control unit ECU0 will be described.

<Rear wheel steering angle control unit ECU2>
FIG. 8 is a functional block diagram of the rear wheel steering angle control unit ECU2. As shown in FIG. 8, the control object (the first control object) of the rear wheel steering angle control unit ECU2 is the rear wheel steering angle δr, and the motor MTr (see FIG. 2) corresponds to ACT1 in FIG. Yes. The rear wheel steering angle control unit A1 corresponds to the first control unit A1 of FIG. 1, and the rear wheel steering angle control unit A1 includes the rear wheel steering ratio control unit A11 corresponding to the first control units A11 to A1i of FIG. A turnability control unit A12 and a rear wheel basic steering angle target value calculation unit A1T corresponding to the control amount calculation unit A1T of the first control means of FIG. 1 are provided.

  The rear wheel steering ratio control unit A11 obtains a rear wheel steering ratio SGr, which is a ratio of the rear wheel steering angle to the front wheel steering angle, based on the vehicle body speed Vx and the table shown in FIG. Thereby, the slip angle of the center of gravity of the vehicle can be reduced to zero or the phase difference between the yaw rate and the lateral acceleration of the vehicle can be reduced.

  The turning ability control unit A12 is provided to improve the turning ability of the vehicle, and specifically, phase delay control or phase inversion control is performed. In these controls, the delay time τph is obtained based on the time differential value dθsw of the rotation angle θsw of the steering wheel and the table shown in FIG. In the phase delay control, when the rear wheels are steered in the same phase with respect to the steering of the front wheels, the steering timing of the rear wheels is delayed by the delay time τph to easily generate the yaw of the vehicle. In phase inversion control, when the rear wheels are steered in the same phase with respect to the steering of the front wheels, the rear wheels are steered in the opposite phase only during the period corresponding to the delay time τph, and the vehicle yaw is actively generated. Be made.

  The rear wheel basic steering angle target value calculation unit A1T applies a process corresponding to the phase delay control or phase inversion control to the value δrgt obtained according to the following equation (4) to perform the rear wheel basic steering corresponding to the basic control amount. An angle target value δrt is obtained. Here, δfa is the actual front wheel steering angle.

δrgt = δfa · SGr (4)

  The adding means B1 adds (superimposes) the rear wheel basic steering angle target value δrt and the rear wheel corrected steering angle target value δrc corresponding to the correction control amount transmitted from the braking / driving force control unit ECU0. A rear wheel steering angle target value (δrt + δrc) corresponding to the first target control amount is obtained.

  The electric motor drive processing unit C1 sends a drive signal to the motor MTr based on the rear wheel steering angle target value (δrt + δrc). Thus, the rear wheel steering angle δr is controlled based on the rear wheel steering angle target value (δrt + δrc).

  The normal operation monitoring means D1 monitors whether the rear wheel steering angle target value (δrt + δrc) or the time change rate (change gradient) of the actual rear wheel steering angle δra is greater than a predetermined normal determination reference value. When the rear wheel steering angle target value (δrt + δrc) or the time change rate (change gradient) of the actual rear wheel steering angle δra is smaller than the normal determination reference value, the rear wheel steering angle control unit ECU2 operates normally. A determination is made, and if it is larger than the normal determination reference value, an abnormality determination of the rear wheel steering angle control unit ECU2 is made.

<Braking / braking force control unit ECU0>
FIG. 11 is a functional block diagram of the braking / driving force control unit ECU0. FIG. 12 is a functional block diagram showing details of the understeer control unit A21, the oversteer control unit A22, the braking μ split control unit A23, and the driving μ split control unit A24 shown in FIG.

  As can be understood from the comparison between FIG. 11 and FIG. 6 and the comparison between FIG. 12 and FIG. 7, the braking / driving force control unit ECU0 in the second embodiment is the braking / driving force control unit ECU0 in the first embodiment. The front wheel correction steering angle control means A2 for calculating the front wheel correction steering angle target value δfc is replaced with the rear wheel correction steering angle control means A2 for calculating the rear wheel correction steering angle target value δrc. Therefore, a detailed description of the braking / driving force control unit ECU0 in the second embodiment is omitted except for this point.

  The rear wheel correction steering angle control means A2 outputs a rear wheel correction steering angle target value δrc based on a value representing the movement state of the vehicle in the yaw direction in order to improve the stability in the movement of the vehicle in the yaw direction. Here, the “value representing the motion state in the yaw direction” is a motion state amount deviation representing the degree of understeer and oversteer, which will be described later, and the braking force difference between the left and right wheels that causes the motion in the yaw direction of the vehicle. It is a driving force difference. The rear wheel correction steering angle control means A2 includes an understeer control unit A21, an oversteer control unit A22, a braking μ-split control unit A23, and a driving μ-split control unit A24 corresponding to the second control units A21 to A2j in FIG. And a rear wheel correction steering angle target value calculation unit A2T corresponding to the control amount calculation unit A2T of the second control means of FIG.

  The understeer control unit A21 automatically adjusts the steering angle of the rear wheels so that the yaw moment of turning outward is decreased or the yaw moment of turning inward is increased during understeering. The oversteer control unit A22 automatically adjusts the rear wheel steering angle so as to decrease the inward turning yaw moment or increase the outward turning yaw moment during oversteering.

  The braking μ-split control unit A23 automatically adjusts the rear wheel steering angle so as to cancel the yaw moment generated by the difference in braking force between the left and right wheels. The driving μ-split control unit A24 automatically adjusts the rear wheel steering angle so as to cancel the yaw moment generated by the difference in driving force between the left and right wheels.

  The rear wheel corrected steering angle target value calculation unit A2T converts the rear wheel corrected steering angle target value δrc corresponding to the correction control amount into the motion state amount deviations ΔVm_us, ΔVm_os, the braking force difference ΔBf, and the driving force difference ΔDf (FIG. 12). As a result, the rear wheel corrected steering angle target value δrc is normally “0”, and when it is necessary to suppress understeer and oversteer, the deflection of the vehicle due to the yaw moment based on the braking / driving force difference between the left and right wheels is suppressed. It is a value other than “0” only when the vehicle needs to be stabilized, such as when it is necessary.

  The rear wheel corrected steering angle target value calculation unit A2T transmits the rear wheel corrected steering angle target value δrc to the adding means B1 in the rear wheel steering angle control unit ECU2, and also transmits a control flag in the rear wheel steering angle control unit ECU2. To the control stop means E1. Thus, the basic control based on the rear wheel basic steering angle target value δrt and the correction control based on the rear wheel corrected steering angle target value δrc are the same rear wheel steering angle δr (MTr).

<Combination in which control interference occurs in the second embodiment>
Of the two first control units in the front wheel steering angle control unit A1 related to the basic control, the rear wheel steering ratio control unit A11 and the second control units A21 to A21 in the rear wheel correction steering angle control unit A2 related to the correction control. Among the A24, the above-described “control interference” may occur among the understeer control unit A21, the braking μ-split control unit A23, and the driving μ-split control unit A24. The “control interference” in this case means the change (instruction) direction of the rear wheel steering angle δr (MTr) based on the calculation result of the rear wheel steering ratio control unit A11, and each of the second control units A21, A23, A24. This means a phenomenon in which the correction (instruction) direction of the rear wheel steering angle δr (MTr) based on the calculation result (the change (instruction) direction of the corrected rear wheel steering angle δr (MTr)) is reversed. Hereinafter, each control interference will be specifically described in order.

<< Rear Wheel Steering Ratio Control Unit A11-Under Steer Control Unit A21 >>
At the time of turning deceleration of the vehicle, as described above, when the steering wheel 21 is held, the front wheels are instructed to turn in the turning inner direction. Therefore, the rear wheel steering ratio control unit A11 instructs the rear wheels to turn in the turning inner direction in the same phase direction as the front wheels. On the other hand, the understeer control unit A21 instructs the rear wheels to turn outward (in the opposite phase direction to the front wheels) in order to reduce the outward yaw moment of turning or to increase the inward turning yaw moment. As a result, the control interference occurs. As described above, when the understeer control unit A21 is in the “operating state”, the rear wheel steering ratio control unit A11 is “stopped”, the rear wheel steering ratio SGr is set to “0”, and the rear wheel is turned in the turning inner direction. It is preferable to suppress the rudder.

<< Rear Wheel Steering Ratio Control Unit A11-braking μ Split Control Unit A23 >>
When braking, the μ split control unit A23 instructs the rear wheels to turn in the direction of the high road surface friction coefficient (in the opposite phase direction to the front wheels) in order to cancel out the yaw moment (the direction of the high road surface friction coefficient) due to the difference in braking force between the left and right wheels. To do. On the other hand, the front wheels are steered in the direction of the low road surface friction coefficient in order to cancel out the yaw moment (the direction of the high road surface friction coefficient) due to the difference in braking force between the left and right wheels. Along with this, the rear wheel steering ratio control unit A11 instructs the rear wheels to steer in the direction of the low road surface friction coefficient in the same phase direction as the front wheels. As a result, the control interference occurs. As described above, when the braking μ-split control unit A23 is in the “operating state”, the rear wheel steering ratio control unit A11 is “stopped”, the rear wheel steering ratio SGf is set to “0”, and the low road surface friction of the rear wheels is set. It is preferable to suppress the steering toward the coefficient side.

<< Rear Wheel Steering Ratio Control Unit A11-Driving μ Split Control Unit A24 >>
The driving μ-split control unit A24 instructs to steer the rear wheels in the direction of the low road surface friction coefficient (in the opposite phase direction to the front wheels) in order to cancel out the yaw moment (the direction of the low road surface friction coefficient) due to the difference in driving force between the left and right wheels. To do. On the other hand, the front wheels are steered in the high road surface friction coefficient side direction in order to cancel out the yaw moment (low road surface friction coefficient side direction) due to the difference in driving force between the left and right wheels. Accordingly, the rear wheel steering ratio control unit A11 instructs the rear wheels to steer in the high road surface friction coefficient side direction in the same phase direction as the front wheels. As a result, the control interference occurs. As described above, when the driving μ-split control unit A24 is in the “operating state”, the rear wheel steering ratio control unit A11 is “stopped”, the rear wheel steering ratio SGf is set to “0”, and the high road surface friction of the rear wheels is set. It is preferable to suppress the steering toward the coefficient side.

<Process for suppressing control interference in the second embodiment>
In the second embodiment, for example, control interference can be suppressed by performing the following processing.
1. The control flag is set to “1” when the rear wheel correction steering angle control unit A2 is in the “operating state”, and is set to “0” when the rear wheel correction steering angle control unit A2 is not in the “operation state”. . When the control flag is “1”, the control stop means E1 in the rear wheel steering angle control unit ECU2 sets only the rear wheel steering ratio control unit A11 that can interfere with any of the second control units A21 to A24. "Stop" (corresponding to the above pattern 2). The correction control function of the rear wheel correction steering angle control means A2 and the control function of the turning ability control unit A12 can be ensured continuously.
2. The control flag has the above 1. Is set in the same manner as Here, in the rear wheel steering angle control, when the phase delay control is executed as the turnability control, the turnability control unit A12 is a control unit associated with the rear wheel steering ratio control A11. For this reason, the above 1. When the control flag is “1”, all the first control units (specifically, the rear wheel steering ratio control unit A11 and the turnability control unit A12) may be “stopped” (in the pattern 1 described above). Equivalent).
3. The control flag is provided for each of the second control units A21 to A24. For each control unit, the control flag corresponding to when the control unit is in the “operating state” is set to “1”, and the control unit is set to “activate”. When it is not in “state”, it is set to “0”. The control stop means E1 “stops” all of the first controllers A11 and A12 based on the values of the four control flags (corresponding to the above pattern 5). In this case, for example, when the control flag corresponding to at least one of the second control units A21, A23, A24 that can interfere with the rear wheel steering ratio control unit A11 is "1", the first control units A11, A12 Are all “stopped”.
4). The control flag is the same as in 3. above. Is set in the same manner as Based on the values of the four control flags, the control stop means E1 selectively selects one of the first control units A11 and A12 that can interfere with the control of the second control unit that is determined to be in the “operating state”. "Stop" (corresponding to the above pattern 6). In this case, for example, when the control flag corresponding to at least one of the second controllers A21, A23, and A24 that can interfere with the rear wheel steering ratio controller A11 is “1”, the rear wheel steering ratio controller A11. Is “stopped”.
5. The control flag is set to “1” when at least one of the second control units A21, A23, and A24 that can interfere with control of any of the first control units is in the “operating state”; 0 "is set. When the control flag is “1”, the control stop unit E1 “stops” all of the first control units A11 and A12 (corresponding to the pattern 3 above).
6). Alternatively, the control stop means E1 is the above-mentioned 5. When the control flag is “1”, only the rear wheel steering ratio control unit A11 that can interfere with any of the second control units A21 to A24 is “stopped” (corresponding to the above pattern 4).

  As described above, after the completion of the “processing for suppressing control interference” described above, the rear wheel basic steering angle target value δrt is gradually increased to a value calculated by the rear wheel basic steering angle target value calculation unit A1T ( (With a predetermined speed)

  The above 1. When the control flag set in the same manner as “1” is “1”, the control stop means E1 may “stop” the normal operation monitoring means D1. In addition, the above 3. When at least one of the four control flags set in the same manner as “1” is “1”, the control stop unit E1 may “stop” the normal operation monitoring unit D1. As a result, the rear wheel steering angle target value δrc abruptly superposed on the rear wheel basic steering angle target value δrt, or the time change rate of the actual rear wheel steering angle δfr. With the rapid increase in (change gradient), it is possible to suppress a situation in which an erroneous determination that the rear wheel steering angle control unit ECU2 is normal is abnormal although it is normal.

(Third embodiment)
Next, a control device according to a third embodiment of the present invention will be described. In the third embodiment, the power steering control unit ECU3 corresponds to the first control unit U1 in FIG. 1, and the braking / driving force control unit ECU0 corresponds to the second control unit U2 in FIG. Hereinafter, the power steering control unit ECU3 and the braking / driving force control unit ECU0 will be described.

<Power steering control unit ECU3>
FIG. 13 is a functional block diagram of the power steering control unit ECU3. As shown in FIG. 13, the control target of the power steering control unit ECU3 (the first control target) is a steering torque T, and the motor MTe (see FIG. 2) corresponds to ACT1 of FIG. The power steering control means A1 corresponds to the first control means A1 of FIG. 1, and the power steering control means A1 corresponds to the first control parts A11 to A1i of FIG. 1, the steering force assist control part A11, the inertia compensation control part. A12, a neutral position return control unit A13, a steering damping control unit A14, and a basic assist torque target value calculation unit A1T corresponding to the control amount calculation unit A1T of the first control means of FIG.

  The steering force assist control unit A11 reduces the operation force of the steering wheel 21 by the driver based on the steering torque Tsw obtained by the steering torque sensor 53 and the vehicle body speed Vx. When the vehicle body speed Vx is low, the reduction amount of the operating force is set to a large value, and the reduction amount is set to a smaller value as the vehicle body speed Vx increases. The inertia compensation control unit A12 compensates for a response delay due to the inertia of the motor MTe used for power steering control. The neutral position return control unit A13 improves the return to the neutral position of the steering wheel 21. The steering attenuation control unit A14 suppresses excessive return of the steering wheel 21 and improves the convergence of the steering.

  The basic assist torque target value calculation unit A1T calculates a basic assist torque target value Tt corresponding to the basic control amount based on the calculation results of the first control units A11 to A14.

  The adding means B1 adds (superimposes) the basic assist torque target value Tt and the correction assist torque target value Tc corresponding to the correction control amount transmitted from the braking / driving force control unit ECU0, to thereby add the first target torque. An assist torque target value (Tt + Tc) corresponding to the control amount is obtained.

  The electric motor drive processing unit C1 sends a drive signal to the motor MTe based on the assist torque target value (Tt + Tc). Thereby, the steering torque T is controlled based on the assist torque target value (Tt + Tc).

  The normal operation monitoring means D1 monitors whether or not the assist torque target value (Tt + Tc) or the time change rate (change gradient) of the steering torque Tsw is larger than a predetermined normal determination reference value. (Tt + Tc) or when the time change rate (change gradient) of the steering torque Tsw is smaller than the normal determination reference value, the normal operation determination of the power steering control unit ECU3 is performed, and the normal determination reference value is smaller than the normal determination reference value. If larger, the abnormality determination of the power steering control unit ECU3 is performed.

<Braking / braking force control unit ECU0>
FIG. 14 is a functional block diagram of the braking / driving force control unit ECU0. FIG. 15 is a functional block diagram showing details of the understeer control unit A21, the oversteer control unit A22, the braking μ split control unit A23, and the driving μ split control unit A24 shown in FIG.

  As can be understood from the comparison between FIG. 14 and FIG. 6 and the comparison between FIG. 15 and FIG. 7, the braking / driving force control unit ECU0 in the third embodiment is the braking / driving force control unit ECU0 in the first embodiment. The front wheel correction steering angle control means A2 for calculating the front wheel correction steering angle target value δfc is replaced with the correction assist torque control means A2 for calculating the correction assist torque target value Tc. Therefore, a detailed description of the braking / driving force control unit ECU0 in the third embodiment is omitted except for this point.

  The correction assist torque control means A2 outputs a correction assist torque target value Tc based on a value representing the movement state of the vehicle in the yaw direction in order to improve the stability in the movement of the vehicle in the yaw direction. Here, the “value representing the motion state in the yaw direction” is a motion state amount deviation representing the degree of understeer and oversteer, which will be described later, and the braking force difference between the left and right wheels that causes the motion in the yaw direction of the vehicle. It is a driving force difference. The correction assist torque control means A2 includes an understeer control unit A21, an oversteer control unit A22, a braking μ split control unit A23, and a driving μ split control unit A24 corresponding to the second control units A21 to A2j in FIG. A correction assist torque target value calculation unit A2T corresponding to the control amount calculation unit A2T of the second control means of FIG. 1 is provided.

  The understeer control unit A21 adjusts the steering torque so as to increase the steering reaction force in the increasing direction of the front wheel steering angle in order to prevent the front wheel steering angle from becoming excessive during understeer. The oversteer control unit A22 applies a steering torque in a decreasing direction of the front wheel steering angle so that the front wheel steering angle is decreased during the oversteering operation (to encourage a countersteer operation).

  During braking, the μ split control unit A23 applies a steering torque so as to prompt the steering wheel operation in a direction to cancel the yaw moment generated by the difference in braking force between the left and right wheels (to encourage the counter steer operation). The driving μ-split control unit A24 applies a steering torque so as to urge the steering wheel operation in a direction to cancel the yaw moment generated by the difference in driving force between the left and right wheels (to urge the counter steer operation).

  The correction assist torque target value calculation unit A2T converts the correction assist torque target value Tc corresponding to the correction control amount into the motion state amount deviations ΔVm_us, ΔVm_os, the braking force difference ΔBf, and the driving force difference ΔDf (see FIG. 15). Ask based on. Accordingly, the corrected assist torque target value Tc is normally “0”, and when it is necessary to suppress understeer and oversteer, it is necessary to suppress the deflection of the vehicle due to the yaw moment based on the braking / driving force difference between the left and right wheels. It is a value other than “0” only when the vehicle needs to be stabilized.

  The correction assist torque target value calculation unit A2T transmits the correction assist torque target value Tc to the adding means B1 in the power steering control unit ECU3 and transmits a control flag to the control stop means E1 in the power steering control unit ECU3. . Thus, the basic control based on the basic assist torque target value Tt and the correction control based on the corrected assist torque target value Tc are the same steering torque T (MTe).

<Combination in which control interference occurs in the third embodiment>
The steering damping control unit A14 of the four first control units in the power steering control unit A1 related to the basic control and the overrunning of the second control units A21 to A24 in the correction assist torque control unit A2 related to the correction control. The “control interference” described above may occur between the steering control unit A22. The “control interference” in this case refers to the change (instruction) direction of the steering torque T (MTe) based on the calculation result of the steering damping control unit A14 and the steering torque T (MTe) based on the calculation result of the oversteer control unit A22. This means a phenomenon in which the correction (instruction) direction (change (instruction) direction of the corrected steering torque T (MTe)) is reversed. Hereinafter, this control interference will be specifically described.

<< Steering damping control unit A14-oversteer control unit A22 >>
The steering damping control unit A14 gives an instruction to apply a steering torque in the direction of increasing the front wheel steering angle in order to prevent the steering wheel 21 from returning too much in the process of returning the steering wheel 21 toward the neutral position. On the other hand, the oversteer control unit A22 gives an instruction to apply a steering torque in the direction of decreasing the front wheel steering angle so that the front wheel steering angle is decreased (to encourage the countersteer operation). As a result, the control interference occurs. As described above, when the oversteer control unit A22 is in the “operating state”, it is preferable to “stop” the steering damping control unit A14 and suppress the application of the steering torque in the increasing direction of the front wheel steering angle.

<Process for suppressing control interference in the third embodiment>
In the third embodiment, for example, the following processing can be performed to suppress control interference.
1. The control flag is set to “1” when the correction assist torque control unit A2 is in the “operating state”, and is set to “0” when the correction assist torque control unit A2 is not in the “operating state”. Then, when the control flag is “1”, the control stopping means E1 in the power steering control unit ECU 3 “stops” only the steering damping control unit A14 that can interfere with any of the second control units A21 to A24 ( Equivalent to pattern 2 above). The correction control function of the correction assist torque control means A2 and the control functions of the first control units A11, A12, A13 can be continuously secured.
2. The control flag is provided for each of the second control units A21 to A24. For each control unit, the control flag corresponding to when the control unit is in the “operating state” is set to “1”, and the control unit is set to “activate”. When it is not in “state”, it is set to “0”. The control stop means E1 “stops” only the steering damping control unit A14 based on the values of the four control flags (corresponding to the above pattern 6). In this case, for example, when the control flag corresponding to the oversteer control unit A22 that can interfere with the steering damping control unit A14 is “1”, the steering damping control unit A14 is “stopped”.

  The basic assist torque target value Tt gradually increases to a value calculated by the basic assist torque target value calculation unit A1T (with a predetermined speed) after the above-described “processing for suppressing control interference” is completed. ) It gets closer.

  The above 1. When the control flag set in the same manner as “1” is “1”, the control stop means E1 may “stop” the normal operation monitoring means D1. In addition, the above 2. When at least one of the four control flags set in the same manner as “1” is “1”, the control stop unit E1 may “stop” the normal operation monitoring unit D1. As a result, the assist torque target value (Tt + Tc) or the time change rate (change gradient) of the steering torque Tsw is rapidly increased by the rapid superimposition of the corrected assist torque target value Tc on the basic assist torque target value Tt. Accordingly, it is possible to suppress an erroneous determination that the power steering control unit ECU3 is abnormal although it is normal.

  The present invention is not limited to the above embodiment and the first to third examples, and various modifications can be employed within the scope of the present invention. For example, in the embodiment and the first to third examples, the second control unit U2 includes the second control unit A2 and the third control unit A3. While the second control means A2 is provided in U2, the third control means A3 may be provided in the third control unit U3 independent of the first and second control units U1 and U2.

  In the first to third embodiments, the steering wheel 21 and the steering wheels FL and FR are mechanically connected in the front wheel steering control mechanism 20, but the steering wheel 21 and the steering wheels FL and FR For a vehicle equipped with a so-called steer-by-wire front wheel steering control mechanism (that is, a mechanism that performs front wheel steering control based on an electrical signal indicating the rotation angle θsw of the steering wheel 21) that is not mechanically connected However, the present invention is applicable. In this case, a rod-like member (so-called joystick) may be used as the steering operation member instead of the steering wheel 21.

It is a functional block diagram of the control device of the vehicle concerning the embodiment of the present invention. 1 is a schematic configuration diagram of a vehicle equipped with a vehicle control device according to a first embodiment of the present invention. FIG. 3 is a functional block diagram relating to a front wheel steering angle control unit shown in FIG. 2. It is the graph which showed the table which prescribed | regulated the relationship between a vehicle body speed and a front-wheel steering ratio. It is the graph which showed the table which prescribed | regulated the relationship between the time differential value of the rotation angle of a steering wheel, and a differential steer angle. It is a functional block diagram regarding the braking / driving force control unit shown in FIG. It is a functional block diagram about the detail of the 2nd control part shown in FIG. It is a functional block diagram regarding the rear-wheel steering angle control unit of the vehicle control apparatus which concerns on 2nd Example of this invention. It is the graph which showed the table which prescribed | regulated the relationship between vehicle body speed and a rear-wheel steering ratio. It is the graph which showed the table which prescribed | regulated the relationship between the time differential value of the rotation angle of a steering wheel, and phase delay time. It is a functional block diagram regarding the braking / driving force control unit of the vehicle control apparatus according to the second embodiment of the present invention. It is a functional block diagram about the detail of the 2nd control part shown in FIG. It is a functional block diagram regarding the power steering control unit of the control apparatus of the vehicle which concerns on 3rd Example of this invention. It is a functional block diagram regarding the braking / driving force control unit of the vehicle control apparatus according to the third embodiment of the present invention. It is a functional block diagram about the detail of the 2nd control part shown in FIG.

Explanation of symbols

  U1, U2, U3 ... 1st, 2nd, 3rd control unit, A1, A2, A3 ... 1st, 2nd, 3rd control means, A11-A1i ... 1st control part, A21-A2j ... 2nd control Part, A31 to A3k ... third control part, E1 ... control stop means

Claims (13)

Based on the state of the vehicle, the calculation result of the one or more first control units has one or more first control units that perform calculations for determining the basic control amount of the vehicle control target. A first control unit comprising first control means for determining the basic control amount based on the first control unit;
Based on the state of the vehicle, the one or a plurality of second control units that perform a calculation for determining a correction control amount of the control target used for the correction of the basic control amount include the one or a plurality of second control units. A second control unit independent of the first control unit, comprising second control means for determining the correction control amount based on a calculation result of the second control unit;
A control object control means for controlling the controlled object on the basis of the target control amount of the control target obtained by adding the correction control amount on the basic control amount,
Determination means for determining whether or not the target control amount to be controlled is in an operating state of the second control means in a state where the target control amount is corrected using the correction control amount;
A vehicle control device comprising:
The control based on the calculation result of the first control unit between the one or more first control units and the one or more second control units is determined as the operating state of the second control means. When the change direction of the target and the correction direction of the control target based on the calculation result of the second control unit can be reversed, all the calculation results of the one or more first control units are held constant. Or a vehicle control device comprising control stop means for gradually returning to zero. A plurality of first control units that perform calculations for determining a basic control amount of a control target of the vehicle based on a state of the vehicle, and the basic control amounts based on a calculation result of the plurality of first control units; A first control unit comprising first control means for determining
Based on the state of the vehicle, the one or a plurality of second control units that perform a calculation for determining a correction control amount of the control target used for the correction of the basic control amount include the one or a plurality of second control units. A second control unit independent of the first control unit, comprising second control means for determining the correction control amount based on a calculation result of the second control unit;
A control object control means for controlling the controlled object on the basis of the target control amount of the control target obtained by adding the correction control amount on the basic control amount,
Determination means for determining whether or not the target control amount to be controlled is in an operating state of the second control means in a state where the target control amount is corrected using the correction control amount;
A vehicle control device comprising:
The change of the control target based on the calculation result of the first control unit between the plurality of first control units and the one or more second control units is determined as the operating state of the second control means. When the direction and the correction direction of the control target based on the calculation result of the second control unit can be reversed, the control target based on the calculation result that is a part of the plurality of first control units The change direction of the control object may be opposite to the correction direction of the control object based on any one of the calculation results of the one or more second control units, or at least one calculation result is held constant or zero A control apparatus for a vehicle, comprising control stop means for gradually returning toward the vehicle. In the vehicle control device according to claim 1 or 2,
The determination means includes
The second control is performed from the time when the correction control amount changes from zero to a value outside the predetermined range including zero until the time when the period during which the correction control amount is maintained within the predetermined range reaches a predetermined period. A vehicle control device configured to determine that the means is in an operating state. In the vehicle control device according to claim 1 or 2,
The determination means includes
A control apparatus for a vehicle configured to determine that the second control means is in an operating state when the correction control amount is outside a predetermined range including zero. In the vehicle control device according to claim 1 or 2,
The determination means includes
The change of the control target based on any one of the calculation results of the one or more first control units, the correction direction of the control target being a part of the plurality of second control units based on the calculation result A period during which at least one of the calculation results is maintained within the predetermined range from a point in time when at least one of the calculation results of the reverse of the direction changes from zero to a value outside the predetermined range including zero is predetermined. A control apparatus for a vehicle configured to determine that the second control means is in an operating state until a time point when the period is reached. In the vehicle control device according to claim 1 or 2,
The determination means includes
The change of the control target based on any one of the calculation results of the one or more first control units, the correction direction of the control target being a part of the plurality of second control units based on the calculation result A control apparatus for a vehicle configured to determine that the second control means is in an operating state when at least one of the calculation results of the one that can be opposite to the direction is outside a predetermined range including zero. A plurality of first control units that perform calculations for determining a basic control amount of a control target of the vehicle based on a state of the vehicle, and the basic control amounts based on a calculation result of the plurality of first control units; A first control unit comprising first control means for determining
A plurality of second control units for performing a calculation for determining a correction control amount of the control target used for correcting the basic control amount based on the state of the vehicle; A second control unit independent of the first control unit, comprising a second control means for determining the correction control amount based on a calculation result;
A control object control means for controlling the controlled object on the basis of the target control amount of the control target obtained by adding the correction control amount on the basic control amount,
For each of the second control units, whether or not the target control amount to be controlled is in an operating state of the second control unit, which is a state where the target control amount is corrected using the calculation result of the second control unit. Determination means for independent determination;
A vehicle control device comprising:
Based on the determination result of the determination means, between the plurality of first control units and the plurality of second control units, the change direction of the control object based on the calculation result of the first control unit and the second When the correction direction of the control target based on the calculation result of the control unit can be reversed, all of the plurality of first control units or a part of the plurality of first control units and the calculation The direction of change of the control object based on the result is at least one of the calculation results that can be opposite to the correction direction of the control object based on the calculation result of the second control unit that is determined to be the operating state. A control apparatus for a vehicle, comprising control stop means for holding or gradually returning toward zero. The vehicle control device according to claim 7,
The determination means includes
From the time when the calculation result of the second control unit changes from zero to a value outside a predetermined range including zero until the time when the period during which the calculation result is maintained within the predetermined range reaches a predetermined period, A vehicle control device configured to determine that the second control unit is in an operating state. The vehicle control device according to claim 7,
The determination means includes
A vehicle control apparatus configured to determine that the second control unit is in an operating state when a calculation result of the second control unit is outside a predetermined range including zero. The vehicle control device according to any one of claims 1 to 9,
The control target control means is a vehicle control device provided in the first control unit. The vehicle control device according to any one of claims 1 to 10,
The determination means is a vehicle control device provided in the second control unit. The vehicle control device according to any one of claims 1 to 11,
The control stop means is a vehicle control device provided in the first control unit. The vehicle control device according to any one of claims 1 to 12,
The control object of the vehicle is a steering angle of a front wheel, a steering angle of a rear wheel, or a steering torque of a steering wheel.

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