JP2009143310A - Cruise control apparatus for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cruise control apparatus for a vehicle capable of controlling yaw behavior of the vehicle, and capable of suppressing roll behavior of the vehicle. <P>SOLUTION: The cruise control apparatus (1) for the vehicle includes braking and driving force outputting means (11 to 14) for outputting braking and driving force to respective wheels, a controlling means (40) for controlling the yaw behavior of the vehicle and for controlling output of the braking and driving force outputting means so as to suppress the roll behavior of the vehicle generated on the basis of suspension characteristics of the vehicle as a result of controlling the yaw behavior of the vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle travel control device that controls output of braking / driving force output means such as an engine, a motor, and a brake to control a yaw behavior of a vehicle.

  Conventionally, research has been conducted on the technology for controlling the yaw behavior of a vehicle by controlling the braking force and driving force output to each wheel based on the vehicle attitude and the driving operation of the driver, and practical application has been attempted. ing.

  For example, in an in-vehicle control system called VSC (Vehicle Stability Control), if the vehicle does not turn even if the steering wheel is turned at overspeed (understeer), the engine output is reduced and the vehicle is braked on the inner rear wheel. When the car starts to spin (oversteer) by a sharp steering operation toward the inside of the corner, the brake is applied to the outer front wheel to control the spin.

  In recent years, research has been conducted on a technique for controlling a vehicle by using a motor that individually drives each wheel. By using such a technique, it becomes possible to more actively control the braking force and driving force output to each wheel and to control the yaw behavior of the vehicle. When a driving motor is provided inside each wheel, the motor is called an in-wheel motor or the like.

As an example of a device that controls the running of a vehicle by a motor that individually drives each wheel, a driving force difference is generated between the left and right front wheels based on a target steering reaction force according to the vehicle speed and the steering angle, and the driver's steering torque is increased. An invention of a driving force control device for a four-wheel independent drive vehicle including a steering torque control means for controlling is disclosed (for example, see Patent Document 1).
JP 2006-187047 A

  In the device described in the above-mentioned conventional Patent Document 1, no consideration is given to the roll behavior of the vehicle that may occur as a result of the output of braking / driving force to each wheel. Therefore, the passenger may feel uncomfortable due to unexpected roll behavior. This is because the braking / driving force output to the left and right wheels is transmitted to the vehicle body as a force having a vertical component through the suspension link particularly in a vehicle in which roll control is performed. This will be described below.

In such a vehicle, as shown in FIG. 10, the instantaneous rotation centers C _A , C _B , C _C , and C _D in the suspension that supports the wheels A, B, C, and D on the vehicle body are the front wheels A and B and the rear wheels C. , D is set so as to be located between the two.

As shown in FIG. 10 (A), the braking torque to the front wheels B is applied, the rearward force F _B acts with respect to the traveling direction of the vehicle to the ground Bg of the front wheel B, thereby the instantaneous center of rotation C _B F _B S having a component force F _B SV in the vertically upward direction acts. That is, a force in a direction to cancel the sinking of the vehicle body caused by braking the front wheel B acts on the vehicle body. Further, for example, when driving torque is applied to the rear wheels D, forward force F _D is applied with respect to the traveling direction of the vehicle to the ground Dg of the front wheel D, thereby the instantaneous center of rotation C _D in the vertical upward direction min _{F D} S having a force _F D SV acts. That is, a force in a direction to cancel the sinking of the vehicle body by driving the front wheel D acts on the vehicle body.

As shown in FIG. 10 (B), when the driving torque is applied to the front wheels A, forward force F _A is applied with respect to the traveling direction of the vehicle to the ground Ag of the front wheel A, thereby the instantaneous center of rotation C _A F _A S having a component force F _A SV in the vertically downward direction acts. That is, a force in a direction to cancel the lifting of the vehicle body by driving the front wheel A acts on the vehicle body. Further, for example, the braking torque to the rear wheel C is applied, rearward force F _C is applied with respect to the traveling direction of the vehicle to the ground Cg of the rear wheel C, thereby the instantaneous center of rotation C _C in the vertical downward direction F _C S having a component force F _C SV acts. That is, a force in a direction to cancel the lifting of the vehicle body by driving the front wheel C acts on the vehicle body.

  In particular, when each wheel is driven by an in-wheel motor, since the driving force is transmitted to each wheel without passing through the drive shaft, the generated roll behavior is further increased.

  The present invention is for solving such problems, and it is a main object of the present invention to provide a vehicular travel control device capable of controlling the yaw behavior of a vehicle and suppressing the roll behavior of the vehicle. To do.

In order to achieve the above object, one embodiment of the present invention provides:
Braking / driving force output means for outputting braking / driving force to each wheel;
Control means for controlling the yaw behavior of the vehicle and for controlling the output of the braking / driving force output means so as to suppress the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle as a result of controlling the yaw behavior of the vehicle When,
There is a vehicular travel control device.

  According to this aspect of the present invention, the braking / driving force output means controls the yaw behavior of the vehicle and suppresses the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle as a result of controlling the yaw behavior of the vehicle. Therefore, the yaw behavior of the vehicle can be controlled and the roll behavior of the vehicle can be suppressed.

In one embodiment of the present invention,
The braking / driving force output means includes, for example, a motor that individually drives each wheel.

In one embodiment of the present invention,
The control means controls the yaw behavior of the vehicle and, as a result of controlling the yaw behavior of the vehicle, the braking / driving force output means of the braking / driving force output means so as to zero the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle. It may be a means for controlling the output.

In one embodiment of the present invention,
The control means includes
When exceeding the output limit of the braking / driving force output means,
Of the outputs of the braking / driving force output means, the output of the braking / driving force output means may be determined by lowering the priority of the output for suppressing the rolling behavior of the vehicle.

In one embodiment of the present invention,
Vehicle speed detection means for detecting the vehicle speed,
The control means may be means for controlling the braking / driving force output means so that the degree of suppression of the roll behavior of the vehicle increases as the vehicle speed detected by the vehicle speed detection means increases.

In one embodiment of the present invention,
Yaw rate detection means for detecting the yaw rate of the vehicle;
Steering angle detection means for detecting the steering angle of the vehicle;
Vehicle speed detection means for detecting the vehicle speed;
Acceleration detecting means for detecting the acceleration of the vehicle,
The control means is based on a deviation between a target yaw rate calculated based on the detected vehicle steering angle, vehicle speed, and lateral acceleration of the vehicle, and a vehicle yaw rate detected by the yaw angular velocity detection means. It may be a means for controlling the yaw behavior of the vehicle by calculating the target yaw moment and controlling the output of the braking / driving force output means so as to realize the calculated target yaw moment.

In one embodiment of the present invention,
Yaw rate detection means for detecting the yaw rate of the vehicle;
Steering angle detection means for detecting the steering angle of the vehicle;
Vehicle speed detection means for detecting the vehicle speed;
The control means calculates a target yaw moment based on a deviation between a target yaw rate calculated based on the detected steering angle and vehicle speed of the vehicle and a yaw rate of the vehicle detected by the yaw angular speed detection means. The output of the braking / driving force output means may be controlled to control the yaw behavior of the vehicle so that the calculated target yaw moment is realized.

  ADVANTAGE OF THE INVENTION According to this invention, while controlling the yaw behavior of a vehicle, the vehicle travel control apparatus which can suppress the roll behavior of a vehicle can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings.

  Hereinafter, a vehicle travel control device 1 according to an embodiment of the present invention will be described. The vehicle travel control device 1 is an electric vehicle that drives, for example, four wheels by an in-wheel motor. The present invention is not limited to this, and a configuration may be adopted in which main power is output from the engine (internal combustion engine) and auxiliary power for yaw behavior control is output from an in-wheel motor disposed on four or two wheels. . Further, it may be configured to include an engine and an electronically controlled brake device capable of outputting braking force independently to the four wheels, or may be configured to include an engine and a driving force distribution differential. The wheel may be driven by an in-wheel motor and a braking force may be output independently from the electronically controlled brake device to the four wheels as necessary.

  That is, any configuration may be used as long as braking / driving force can be individually output to each wheel. In the following embodiments, four wheels are described as a configuration in which each wheel is driven by an in-wheel motor.

[Constitution]
FIG. 1 is a diagram illustrating an example of the overall configuration of the vehicle travel control device 1. The vehicle travel control device 1 includes, as main components, a battery 10, in-wheel motors 11, 12, 13, 14 disposed on each wheel, an inverter 20, a vehicle speed sensor 30, a yaw rate sensor 31, A steering angle sensor 32, a G sensor 33, an accelerator opening sensor 35, and an ECU (Electronic Control Unit) 40 are provided. The arrows in the figure indicate the flow of main information communication in the vehicle that is performed using an appropriate communication protocol such as CAN (Controller Area Network), BEAN, AVC-LAN, or FlexRay via multiple communication lines.

  The battery 10 is a fuel cell capable of continuously supplying power by continuously supplying a fuel such as hydrogen and an oxidant such as oxygen. Further, the present invention is not limited to this, and a secondary battery that can be charged and discharged may be used. In the latter case, the battery 10 may be charged using power output from a separately provided engine or may be charged by solar power generation. Of course, charging may be performed by regenerative control of the in-wheel motors 11, 12, 13, and 14.

  Each in-wheel motor is, for example, a three-phase synchronous generator motor in which a permanent magnet is embedded in a rotor, and the output torque is individually controlled by the inverter 20. Each in-wheel motor has a rotor connected to a wheel side (rotation side) and a stator connected to a vehicle body side (non-rotation side). The vehicle body side connecting portion of each in-wheel motor is connected to the vehicle body via a suspension structure. Here, the suspension structure of the vehicle on which the present apparatus is mounted has a well-known structure (geometry) for connecting the wheel to the vehicle body with a predetermined caster angle or camber angle. In-wheel motors 11 and 12 drive front wheels, and in-wheel motors 13 and 14 drive rear wheels.

  The inverter 20 converts the DC power supplied from the battery 10 into a three-phase AC and supplies it to each in-wheel motor.

  The vehicle speed sensor 30 includes, for example, a wheel speed sensor attached to each wheel and a skid control computer. The skid control computer converts a wheel speed pulse signal output from the wheel speed sensor into a vehicle speed rectangular wave pulse signal (vehicle speed signal). To the ECU 40.

  The yaw rate sensor 31 is attached, for example, below the center console portion of the vehicle, detects the rotational angular velocity (= yaw rate) around the vertical axis of the vehicle based on the distortion amount and direction of the piezoelectric ceramics, and outputs the rotational angular velocity to the ECU 40.

  For example, the steering angle sensor 32 is disposed inside the steering column, detects the turning angle of the steering wheel, and outputs the detected steering angle signal to the ECU 40.

  The G sensor 33 is, for example, a biaxial G sensor that is mounted below the center console portion of the vehicle, measures the distortion of the beam in the sensor that occurs according to the acceleration of the vehicle, and outputs it by replacing it with an electrical signal. It is. The G sensor 33 is composed of a combination of two G sensors mounted at different angles with respect to the longitudinal direction of the vehicle, and it is possible to detect acceleration in all horizontal directions by combining these detection values. is there. The output value of the G sensor 33 is input to the ECU 40.

  The accelerator opening sensor 35 is attached to an accelerator pedal, for example, and takes out the gradient of the magnetic field according to the accelerator opening (operation amount) as an output voltage linearly using a Hall element. The accelerator opening sensor 35 transmits the accelerator opening (operation amount) thus detected to the ECU 40.

  The ECU 40 is a computer unit in which a ROM, a RAM, and the like are connected to each other via a bus with a CPU at the center. , Timer, counter, etc. The ROM stores programs and data executed by the CPU. The ECU 40 generates a signal wave (carrier) representing the current application timing, voltage value, current value, duty ratio, and the like when the inverter 20 supplies power to each in-wheel motor, and outputs the signal wave (carrier) to the inverter 20.

[Basic control]
As a basic control, the ECU 40 calculates a target torque to be output as the entire vehicle based on the accelerator opening detected by the accelerator opening sensor 35 and the vehicle speed detected by the vehicle speed sensor 30, and this is calculated for each. Distribute to the in-wheel motor with a predetermined distribution ratio. And a carrier is produced | generated individually about each in-wheel motor so that the allocated torque may be output. Note that, as described above, the main power output may be output by the engine.

  Further, the ECU 40 performs so-called direct yaw moment control control (DYC) in addition to the control of each in-wheel motor based on the accelerator opening as control for controlling the yaw behavior of the vehicle. Such control calculates, for example, a direct yaw moment (target yaw moment) DYM for suppressing an undesired yaw behavior caused by slipping of a vehicle, and outputs each direct yaw moment DYM. It increases or decreases the output of the in-wheel motor.

  The direct yaw moment DYM is obtained by, for example, multiplying a difference Δγ between a target yaw rate Yr *, which is an ideal yaw rate generated by a vehicle speed and a steering angle, and a yaw rate (actual yaw rate) Yr detected by the yaw rate sensor 31 by a predetermined coefficient. (Refer to the following formula (1)). In equation (1), m is the vehicle weight, g is the acceleration of gravity, YG is the yaw gain, Cpf is the front cornering power, Cpr is the rear cornering power, and lf is the front axis and the center of gravity. , Lr is the distance between the rear axle and the center of gravity, V is the vehicle speed, and Kh is the stability factor.

  Further, the target yaw rate Yr * is calculated by the following equation (2), for example. In Expression (2), Str is a steering angle, n is a steering gear ratio, WB is a wheel base, and Gy is a lateral acceleration of the vehicle. In addition, the part of “-Kh · Gy” in the formula (2) may be omitted.

  Yr * = V · (Str / (n · WB) −Kh · Gy) (2)

  Then, the braking / driving force to be output by each in-wheel motor necessary for generating the direct yaw moment DYM is calculated and summed with the output of each in-wheel motor based on the accelerator opening described above, Determine the motor output.

  In addition, the present invention is not limited to the control based on the difference between the target yaw rate Yr * and the actual yaw rate Yr, but outputs braking force from the in-wheel motor disposed on the inner wheel when the vehicle understeer is large (or driving force). May be controlled).

  Such control makes it possible to appropriately control the yaw behavior of the vehicle. Therefore, smoother cornering is realized.

[3_1. Characteristic control contents (1)]
However, the control for controlling the yaw behavior of the vehicle may cause an unexpected roll behavior in the vehicle. This is because the braking / driving force output to the left and right wheels is transmitted to the vehicle body as a force having a vertical component through the suspension link particularly in a vehicle in which roll control is performed. This will be described below.

In such a vehicle, as shown in FIG. 10, the instantaneous rotation centers C _A , C _B , C _C , and C _D in the suspension that supports the wheels A, B, C, and D on the vehicle body are the front wheels A and B and the rear wheels C. , D is set so as to be located between the two.

As shown in FIG. 10 (A), the braking torque to the front wheels B is applied, the rearward force F _B acts with respect to the traveling direction of the vehicle to the ground Bg of the front wheel B, thereby the instantaneous center of rotation C _B F _B S having a component force F _B SV in the vertically upward direction acts. That is, a force in a direction to cancel the sinking of the vehicle body caused by braking the front wheel B acts on the vehicle body. Further, for example, when driving torque is applied to the rear wheels D, forward force F _D is applied with respect to the traveling direction of the vehicle to the ground Dg of the front wheel D, thereby the instantaneous center of rotation C _D in the vertical upward direction min _{F D} S having a force _F D SV acts. That is, a force in a direction to cancel the sinking of the vehicle body by driving the front wheel D acts on the vehicle body.

As shown in FIG. 10 (B), when the driving torque is applied to the front wheels A, forward force F _A is applied with respect to the traveling direction of the vehicle to the ground Ag of the front wheel A, thereby the instantaneous center of rotation C _{A F a} S having a component force _F a SV of vertically downward direction acts. That is, a force in a direction to cancel the lifting of the vehicle body by driving the front wheel A acts on the vehicle body. Further, for example, the braking torque to the rear wheel C is applied, rearward force F _C is applied with respect to the traveling direction of the vehicle to the ground Cg of the rear wheel C, thereby the instantaneous center of rotation C _C in the vertical downward direction F _C S having a component force F _C SV acts. That is, a force in a direction to cancel the lifting of the vehicle body by driving the front wheel C acts on the vehicle body.

  In particular, when each wheel is driven by an in-wheel motor, since the driving force is transmitted to each wheel without passing through the drive shaft, the generated roll behavior is further increased.

Therefore, in the vehicle travel control device 1 of the present embodiment, the yaw behavior of the vehicle is controlled, and the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle as a result of controlling the yaw behavior of the vehicle is controlled. The output of each in-wheel motor was decided. Here, the suspension characteristic of the vehicle specifically refers to a front wheel anti-dive coefficient Anf and a rear wheel anti-lift coefficient Anr. Incidentally, in FIG. 10, the direction and the ground angle of connecting the ground points Ag and instantaneous rotation center C _A of the front wheel A (= ground point connecting the Bg and the instantaneous center of rotation C _B direction and the ground angle of the front wheels B) anti-dive angle .theta.f, direction and the ground angle of the ground point Cg and instantaneous connecting the rotational center C _C of the rear wheel C a (= ground point Dg and the instantaneous center of rotation C _D connecting direction and the ground angle of the front wheels D) When the anti-lift angle θr is assumed, the front wheel anti-dive coefficient Anf is tan (θf), and the rear wheel anti-lift coefficient Anr is tan (θr).

  The “unexpected” roll behavior means not a natural roll behavior caused by a normal cornering force but a roll behavior produced according to the suspension characteristics by the control for controlling the yaw behavior of the vehicle described above.

  The following equation (3) shows a vehicle model related to generation of a general roll moment Rm generated in the vehicle. In the equation, Hcg is the height of the center of gravity, lt is the tread width, Fx1 to 4 are braking / driving forces output from the in-wheel motors 11 to 14 (torque or force acting on the contact surface; hereinafter, the torque is determined. As described below).

  In the above equation (3), the third term on the right side indicates the roll moment generated according to the suspension characteristics by the control for controlling the yaw behavior of the vehicle. Therefore, the unexpected roll behavior of the vehicle can be suppressed by reducing Anf (−Fx1 + Fx2) + Anr (−Fx3 + Fx4). When DYM is expressed using Fx1 to Fx4, the following equation (4) is obtained.

  In order to implement such control, in the vehicle travel control device 1 of the present embodiment, an output determination map that prescribes combinations of Fx1 to Fx4 is stored in advance in the ROM or the like of the ECU 40, and Fx1 4 was decided. FIG. 2 shows the relationship between the output torque of each in-wheel motor (hereinafter, for the sake of simplicity, excluding the output torque of each in-wheel motor based on the accelerator opening) Fx1 to Fx 4 and the target yaw moment Yr *. It is an example of the map for output determination to prescribe | regulate. As shown in the figure, Fx1 and Fx2, Fx3 and Fx4 are set to be contrast values with opposite signs, and the ratio of Fx1 and Fx2 to Fx3 and Fx4 is constant. This ratio is determined according to the front wheel anti-dive coefficient Anf and the rear wheel anti-lift coefficient Anr. Therefore, by determining Fx1 to Fx4 according to the output determination map, the roll behavior of the vehicle generated according to the suspension characteristics as a result of controlling the yaw behavior of the vehicle can be made zero.

  In the map illustrated in FIG. 2, Fx1 to Fx4 may completely satisfy the conditions for the output determination map, but the map may be reflected with a certain degree of error or tolerance. This is because by setting such an allowable range, the output of each in-wheel motor for controlling the yaw behavior of the vehicle can be set more flexibly.

  According to the vehicle travel control apparatus 1 of the present embodiment, the output torque of each in-wheel motor is determined so that the roll moment generated according to the suspension characteristics is reduced by the control for controlling the yaw behavior of the vehicle. Accordingly, the yaw behavior of the vehicle can be controlled, and the unexpected roll behavior of the vehicle can be suppressed, so that yaw control with good driver feeling can be realized.

  FIG. 3 is an example of a flowchart showing a flow of processing executed by the ECU 40 in order to realize the above control. First, the vehicle speed V, the steering angle Str, and the lateral acceleration Gy are input from the vehicle speed sensor 30, the steering angle sensor 32, and the G sensor 33 (S100), and the target yaw rate Yr * is calculated as described above (S100). S102).

  Subsequently, the actual yaw rate Yr is input from the yaw rate sensor 31 (S104).

  Then, the direct yaw moment DYM is calculated based on the difference between the target yaw rate Yr * and the actual yaw rate Yr (S106).

  When the direct yaw moment DYM is calculated, appropriate output torques Fx1 to Fx1 to Fx1 to 4 of each in-wheel motor are derived with reference to an output determination map stored in advance in a ROM or the like (S108), and these are based on the accelerator opening. The final output torque of each in-wheel motor is determined by adding to the output torque of each in-wheel motor (S110).

[3_2. Characteristic control content (2)]
Further, each in-wheel motor is controlled so as to suppress not only the roll moment generated according to the suspension characteristics by the control for controlling the yaw behavior of the vehicle but also the roll moment generated directly by the influence of the direct yaw moment DYM. The output may be determined. That is, the outputs Fx1 to Fx1 of the in-wheel motors are determined so that both the second term and the third term in the above formula (3) become small. In this way, the roll behavior itself generated in the vehicle can be reduced.

  In this case, the outputs Fx1 to Fx1 to 4 of each in-wheel motor are determined within the range of the output determination map as shown in FIG. 4, for example, instead of complying with the output determination map illustrated in FIG. Therefore, the degree of freedom of Fx1 to Fx4 becomes higher, and these can be determined by a trade-off with the total energy.

  According to such control, it is possible to suppress the generated roll behavior while realizing the target yaw rate Yr *. Therefore, yaw control with good driver feeling is realized.

[3_3. Characteristic control content (3)]
Further, when the output torque (or output power) of any in-wheel motor exceeds the output limit, the output priority order for suppressing the roll behavior of the vehicle is lowered, and the outputs Fx1 to Fx1 of each in-wheel motor are reduced. 4 may be determined.

  In this case, for example, the outputs Fx1 to Fx1 of each in-wheel motor are determined using an output determination map as shown in FIG. As shown in the drawing, when the output of the in-wheel motors 11 and 12 reaches the limit (in the figure, Yr * = right side of the control point of Y1), when the target yaw moment Yr * further increases, the in-wheel Prioritize the realization of the target yaw moment Yr * by increasing the outputs of the motors 13 and 14 (basically, it is normal to output a larger torque from the in-wheel motor on the front wheel side than on the rear wheel side. ).

  FIG. 6 is an example of an output determination map when the priority order for reducing the roll moment is not changed even when the output torque (or output power) of any in-wheel motor exceeds the output limit. In such a case, the target yaw moment Yr * cannot be satisfied on the right side of the control point of Yr * = Y1. In view of safety, it is considered that yaw control should be given priority over driver feeling, so it is more appropriate to use a map as shown in FIG.

  Normally, since the output limit of the motor exists in both torque and power, it is assumed that Y1 indicating the output limit is not a constant value. In this case, the output determination map illustrated in FIG. 2 is basically used, and when any in-wheel motor reaches the output limit, the map to be used is dynamically switched (or generated at that time). And it is sufficient.

  According to such control, the yaw behavior of the vehicle can be controlled, the unexpected roll behavior of the vehicle can be suppressed, and further safe driving can be realized.

[3_4. Characteristic control content (4)]
Further, the degree of compliance with the map illustrated in FIG. 2 or 5 may be changed according to the vehicle speed detected by the vehicle speed sensor 30. This is because when the vehicle speed is high, the driver's roll sensitivity is considered high, and when the vehicle speed is low, the driver's roll sensitivity is low and the necessity of yaw control is considered high.

  Here, in order to change the degree of compliance, an allowable range may be set for the output determination map, but a control gain K for the target torque defined by the output determination map may be changed. In the latter case, for example, the control gain K is determined based on a control gain changing map as shown in FIG. The control gain K may be individually changed for each in-wheel motor (gains K1 to K4 are set by a control gain change map for each in-wheel motor).

  With such control, more flexible control can be performed based on the required characteristics that change according to the vehicle speed.

  FIG. 8 is a flowchart showing a flow of processing executed by the ECU 40 in order to realize both [characteristic control content (3)] and [characteristic control content (4)].

  First, a vehicle speed V, a steering steering angle Str, and a lateral acceleration Gy are respectively input from the vehicle speed sensor 30, the steering steering angle sensor 32, and the G sensor 33 (S200), and the target yaw rate Yr * is calculated as described above (S200). S202).

  Subsequently, the actual yaw rate Yr is input from the yaw rate sensor 31 (S204), and the direct yaw moment DYM is calculated based on the difference between the target yaw rate Yr * and the actual yaw rate Yr (S206).

  When the direct yaw moment DYM is calculated, the control gain for the target torque is derived by referring to the control gain changing map using the vehicle speed V (S208). Subsequently, the output determination map as illustrated in FIG. 5 is corrected using the derived control gain (S210). FIG. 9 is a diagram illustrating an output determination map modified according to the vehicle speed.

  Then, the outputs Fx1 to Fx1 to 4 of each in-wheel motor are determined using the corrected output determination map (S212), and these are added to the output torque of each in-wheel motor based on the accelerator opening, The final output torque is determined (S214).

  According to the vehicle travel control device 1 of the present embodiment, it is possible to control the yaw behavior of the vehicle and to suppress the roll behavior of the vehicle.

  The best mode for carrying out the present invention has been described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. And substitutions can be added.

  The present invention can be used in the automobile manufacturing industry, the automobile parts manufacturing industry, and the like.

1 is a diagram illustrating an example of an overall configuration of a vehicle travel control device 1 according to an embodiment of the present invention. It is an example of the output determination map which prescribes | regulates the relationship between the output torque Fx1-4 of each in-wheel motor, and the target yaw moment Yr *. It is an example of the flowchart which shows the flow of the process performed by ECU40. It is another example of the map for output determination. It is another example of the map for output determination. It is another example of the map for output determination. It is a figure which shows an example of the map for control gain change which prescribes | regulates the relationship between a vehicle speed and the control gain with respect to a target torque. It is another example of the flowchart which shows the flow of the process performed by ECU40. It is a figure which illustrates the map for output determination corrected according to the vehicle speed. It is explanatory drawing for demonstrating the mechanism in which a vertical force generate | occur | produces in the vehicle in which roll control is performed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle travel control apparatus 10 Battery 11, 12, 13, 14 In-wheel motor 20 Inverter 30 Vehicle speed sensor 31 Yaw rate sensor 32 Steering steering angle sensor 33 G sensor 35 Accelerator opening sensor 40 ECU

Claims (7)

Braking / driving force output means for outputting braking / driving force to each wheel;
Control means for controlling the yaw behavior of the vehicle and for controlling the output of the braking / driving force output means so as to suppress the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle as a result of controlling the yaw behavior of the vehicle When,
A vehicle travel control apparatus comprising: The braking / driving force output means includes a motor that individually drives each wheel.
The vehicle travel control apparatus according to claim 1. The control means controls the yaw behavior of the vehicle and, as a result of controlling the yaw behavior of the vehicle, the braking / driving force output means of the braking / driving force output means so as to zero the roll behavior of the vehicle that occurs according to the suspension characteristics of the vehicle. A means of controlling the output,
The vehicle travel control apparatus according to claim 1 or 2. The control means includes
When exceeding the output limit of the braking / driving force output means,
Of the outputs of the braking / driving force output means, means for determining the output of the braking / driving force output means by lowering the priority of the output for suppressing the roll behavior of the vehicle.
The vehicle travel control apparatus according to any one of claims 1 to 3. Vehicle speed detection means for detecting the vehicle speed,
The control means is means for controlling the braking / driving force output means so that the degree of suppression of the roll behavior of the vehicle increases as the vehicle speed detected by the vehicle speed detection means increases.
The vehicle travel control apparatus according to any one of claims 1 to 4. Yaw rate detection means for detecting the yaw rate of the vehicle;
Steering angle detection means for detecting the steering angle of the vehicle;
Vehicle speed detection means for detecting the vehicle speed;
Acceleration detecting means for detecting the acceleration of the vehicle,
The control means is based on a deviation between a target yaw rate calculated based on the detected vehicle steering angle, vehicle speed, and lateral acceleration of the vehicle, and a vehicle yaw rate detected by the yaw angular velocity detection means. A means for calculating a target yaw moment and controlling the output of the braking / driving force output means so as to realize the calculated target yaw moment to control the yaw behavior of the vehicle;
The vehicle travel control apparatus according to any one of claims 1 to 5. Yaw rate detection means for detecting the yaw rate of the vehicle;
Steering angle detection means for detecting the steering angle of the vehicle;
Vehicle speed detection means for detecting the vehicle speed;
The control means calculates a target yaw moment based on a deviation between a target yaw rate calculated based on the detected steering angle and vehicle speed of the vehicle and a yaw rate of the vehicle detected by the yaw angular speed detection means. , A means for controlling the yaw behavior of the vehicle by controlling the output of the braking / driving force output means so that the calculated target yaw moment is realized,
The vehicle travel control apparatus according to any one of claims 1 to 5.

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