WO2023210535A1

WO2023210535A1 - Control device for vehicle

Info

Publication number: WO2023210535A1
Application number: PCT/JP2023/015965
Authority: WO
Inventors: 寛生阿部; 亮蜂須賀; 俊輔松尾
Original assignee: 三菱自動車工業株式会社
Priority date: 2022-04-28
Filing date: 2023-04-21
Publication date: 2023-11-02

Abstract

A control device (10) for a vehicle (1) having a yaw rate detection means (21) and a lateral acceleration detection means (22) is provided with a roll angle acquisition unit (11) that acquires a roll angle (θ) of the vehicle (1), a load shift amount estimation unit (12), and a vertical load estimation unit (13). The load shift amount estimation unit (12) estimates at least one of: a load shift amount (ΔW_{y_f}) between left and right wheels of front wheels (2F) on the basis of the roll angle (θ), a lateral force (Y_f) of the front wheels (2F), a front wheel roll damping coefficient (c_f), and a front wheel roll stiffness (k_f); and a load shift amount (ΔW_{y_r}) of left and right wheels of rear wheels (2R) on the basis of the roll angle (θ), a lateral force (Y_r) of the rear wheels (2R), a rear wheel roll damping coefficient (c_r), and a rear wheel roll stiffness (k_r). The vertical load estimation unit (13) estimates, on the basis of the estimated load shift amount (ΔW_{y_f}, ΔW_{y_r}), vertical loads (Z₁ to Z₄) of wheels 2 which are the front and/or rear wheels (2F, 2R) for which the load shift amount (ΔW_{y_f}, ΔW_{y_r}) has been estimated.

Description

Vehicle control device

The present case relates to a control device that estimates the vertical load on at least one of the front wheels and rear wheels of a vehicle.

A vehicle is equipped with a plurality of detection means (for example, sensors) that detect the driving state, the state of on-vehicle equipment, etc., and various vehicle motion controls are implemented based on the detected values. For example, Patent Document 1 discloses various devices that calculate and output state quantities related to vehicle states from detection results by various sensors. This device calculates the ground contact load variation, which is the variation in the ground contact load (vertical load) of the wheels, and uses this ground contact load variation as an input value for feedback control to account for load fluctuations caused by road surface displacement (disturbance). It is now possible to make estimates. Note that Patent Document 1 discloses a technique for controlling suspension damping force and steering torque using this estimation result.

JP2019-089504A

In the technique of Patent Document 1 mentioned above, the ground contact load fluctuation is calculated with reference to the wheel angular velocity, the estimated value of the sprung longitudinal speed, the estimated value of the pitch rate, and the estimated value of the yaw rate. As described above, the technique disclosed in Patent Document 1 attempts to realize advanced vehicle body attitude control including roll, pitch, and bounce, and accordingly, there are many state quantities to be estimated, making calculations complicated. For this reason, for vehicles that do not require such sophisticated body posture control, it would be possible to estimate the ground load using a simpler method and using general-purpose detection means that are standard equipment on the vehicle. It can be used for various vehicle motion control.

The present invention was devised in view of such problems, and the object is to provide a vehicle control device that estimates the vertical load on at least one of the front wheels and the rear wheels using a simple method using a general-purpose detection means. is one of the objectives. In addition, other purposes of the present invention are not limited to this purpose, but also to achieve functions and effects that are derived from each configuration shown in the detailed description of the invention and that cannot be obtained by conventional techniques. be.

The disclosed vehicle control device can be realized as the embodiments or application examples disclosed below, and solves at least part of the above problems.
The disclosed vehicle control device is applied to the vehicle provided with yaw rate detection means for detecting the yaw rate of the vehicle and lateral acceleration detection means for detecting the lateral acceleration of the vehicle. The control device includes a roll angle acquisition unit that acquires a roll angle of the vehicle, and a roll angle acquisition unit that acquires a roll angle of the vehicle, and a roll angle acquisition unit that acquires a roll angle of the vehicle, and a roll angle acquisition unit that acquires a roll angle of the vehicle. The load transfer amount between the left and right wheels of the front wheels, the acquired roll angle, the lateral force of the rear wheels, the rear wheel roll damping coefficient regarding the rear wheels, and the rear wheel roll rigidity regarding the rear wheels. a load movement amount estimating unit that estimates at least one of the amount of load movement between the left and right wheels of the rear wheel; and a vertical load estimator that estimates each vertical load of at least one wheel.

According to the disclosed vehicle control device, each vertical load (ground load) of at least one of the front wheels and the rear wheels can be estimated by a simple method using a general-purpose detection means.

FIG. 1 is a diagram illustrating the configuration of a vehicle to which a control device according to an embodiment is applied. 2 is a diagram showing a load movement estimation model used in the control device of FIG. 1. FIG. 2 is a diagram showing a load movement estimation model used in the control device of FIG. 1. FIG. 2 is a diagram showing a load movement estimation model used in the control device of FIG. 1. FIG. 2 is an example of a flowchart executed by the control device of FIG. 1. FIG.

A vehicle control device as an embodiment will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude the application of various modifications and techniques not specified in the embodiments below. The configuration of each embodiment can be modified and implemented in various ways without departing from the spirit thereof. Moreover, they can be selected or combined as necessary. In the following description, the forward direction of the vehicle is defined as the front (front of the vehicle), and left and right are defined with the front as a reference.

[1. Device configuration]
The control device 10 of this embodiment is applied to the vehicle 1 illustrated in FIG. 1, and estimates the vertical load (also called ground load or wheel load) of at least one of the front wheels 2F and rear wheels 2R of the vehicle 1. have a function. The control device 10 is a device implemented as one of the electronic control units (ECUs) mounted on the vehicle 1. The control device 10 is equipped with a processor (microprocessor) such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a nonvolatile memory, and the like.

A processor is an arithmetic processing device that includes a control unit (control circuit), an arithmetic unit (arithmetic circuit), a cache memory (register group), etc. Further, ROM, RAM, and nonvolatile memory are memory devices in which programs and data being worked on are stored. The contents of the estimation executed by the control device 10 are recorded and stored in memory as firmware or an application program, and when the program is executed, the contents of the program are developed in the memory space and executed by the processor.

The type of vehicle 1 is not particularly limited, and it can be applied to an engine vehicle, an electric vehicle (EV), an electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a fuel cell vehicle (FCV). be. The vehicle 1 is equipped with an actuator related to the operation of the vehicle 1 and a notification device that makes an announcement to the driver by voice or display. The actuator includes, for example, a drive source such as an engine or an electric motor, a brake device that brakes each wheel 2 independently, a power steering device, each turning amount of the front wheels 2F and the rear wheels 2R (front wheel steering angle, rear wheel steering angle, etc.). Active suspensions include AFS (Active Front Steering) and ARS (Active Rear Steering), which can actively control the angles.

The actuator is a device that converts energy into mechanical displacement or stress, and is individually controlled by an on-vehicle control device (not shown). An individual on-vehicle control device may be provided for each actuator, or a common on-vehicle control device may control different actuators. Furthermore, the on-vehicle control device that controls the notification device may be provided separately from the on-vehicle control device that controls the actuator. In this embodiment, the estimation results estimated by the control device 10 are sent to each vehicle-mounted control device, and are used to control actuators and notification devices. Note that the control device 10 may also have a function of controlling the actuator and the notification device. That is, the control device 10 may be configured to have both an estimation function and a control function.

The vehicle 1 is provided with a sensor for acquiring various information about the vehicle 1. In the example shown in FIG. 1, a yaw rate sensor 21, a lateral acceleration sensor 22, and a longitudinal acceleration sensor 23 are provided, and each of the sensors 21 to 23 is connected to the control device 10. The yaw rate sensor 21 (yaw rate detection means) is a sensor that detects the rotational angular velocity around a vertical axis passing through the center of gravity G of the vehicle 1 as a yaw rate r. In this embodiment, as shown by the thick arrow in FIG. 1, the positive direction of the yaw rate r is counterclockwise around the center of gravity G when the vehicle 1 is viewed from above.

The lateral acceleration sensor 22 (lateral acceleration detection means) and the longitudinal acceleration sensor 23 (longitudinal acceleration detection means) are sensors that respectively detect lateral acceleration A _y and longitudinal acceleration A _x at the center of gravity G of the vehicle 1. In this embodiment, as shown by thick arrows in FIG. 1, the positive direction of the lateral acceleration A _y is to the left from the center of gravity G, and the positive direction of the longitudinal acceleration A _x is toward the front from the center of gravity G. It is said that Information detected by each sensor 21 to 23 is sent to the control device 10. In addition to these sensors 21 to 23, the vehicle 1 is provided with general-purpose sensors such as a vehicle speed sensor that detects vehicle speed, a wheel speed sensor that detects wheel speed, and a steering angle sensor that detects steering angle. You can leave it there.

The means for detecting the yaw rate r, the means for detecting the lateral acceleration _Ay , and the means for detecting the longitudinal acceleration _Ax are not limited to the yaw rate sensor 21, the lateral acceleration sensor 22, and the longitudinal acceleration sensor 23. For example, the lateral acceleration A _y can be estimated based on the steering angle and vehicle speed, or by correcting the estimated value or the value detected by the lateral acceleration sensor 22 based on another sensor value _. It may be detected (obtained). Similarly, the yaw rate r and the longitudinal acceleration A _x may be detected (obtained) by correcting the values detected by the yaw rate sensor 21 and the longitudinal acceleration sensor 23 based on other sensor values. In such a case, the estimation section and the correction section (functional elements of the control device) can serve as each detection means.

[2. Control configuration]
The control device 10 of the present embodiment uses information detected by various sensors 21 to 23 to control at least the vertical loads Z ₁ and Z ₂ of the front wheels 2F of the vehicle 1 and the vertical loads Z ₃ and Z ₄ of the rear wheels 2R. It has the function of estimating one side. The control device 10 also has the function of estimating the estimated vertical load of the lateral forces Y ₁ to Y ₄ of the wheels 2.

For example, if the control device 10 has the function of estimating only the vertical loads Z ₃ and Z ₄ of the rear wheels 2R, it can also have the function of estimating the lateral forces Y ₃ and Y ₄ of the rear wheels 2R. In this embodiment, a case is illustrated in which vertical loads Z ₁ to Z ₄ of all four wheels are estimated, and lateral forces Y ₁ to Y ₄ of all four wheels are also estimated. Here, in the codes indicating the vertical loads Z ₁ to Z ₄ and the lateral forces Y ₁ to Y ₄ , the subscript numbers 1 to 4 are in the order of left front wheel 2FL, right front wheel 2FR, left rear wheel 2RL, and right rear wheel 2RR. Attach.

The control device 10 includes a roll angle acquisition section 11, a load movement amount estimation section 12, and a vertical load estimation section 13 as functional elements for estimating the vertical loads Z ₁ to Z ₄ . Furthermore, the control device 10 of the present embodiment further includes a lateral force estimation unit 14 as a functional element for estimating the lateral forces Y ₁ to Y ₄ using the estimated vertical loads Z ₁ to Z ₄ . These elements are shown by classifying the functions of the control device 10 for convenience. Each of these elements can be written as an independent program, and can also be written as a composite program that combines a plurality of elements. A program corresponding to each element is stored in the memory or storage device of the control device 10 and executed by the processor.

The roll angle acquisition unit 11 acquires the roll angle θ of the vehicle 1. The method for obtaining the roll angle θ is not particularly limited, and similarly to the sensors 21 to 23 described above, a sensor capable of detecting the roll angle θ may be provided and a sensor value or a correction value of the sensor value may be obtained as the roll angle θ. Alternatively, the value (roll angle θ) may be obtained by estimating the roll angle θ based on the sensor value and vehicle specifications. Here, an example of the latter method, that is, a method of estimating and acquiring the roll angle θ, will be described.

The roll angle acquisition unit 11 obtains a vehicle roll damping coefficient which is the sum of the lateral acceleration A _y detected by the lateral acceleration sensor 22, a front wheel roll damping coefficient c _f for the front wheels 2F, and a rear wheel roll damping coefficient _cr for the rear wheels 2R. c (=c _f +c _r ), the roll angle θ of the vehicle 1 is estimated. As shown in FIG. 2, the vehicle roll damping coefficient c is a proportionality constant (damping coefficient in the roll direction) of a component proportional to the roll angular velocity of the moment that acts as a resistance to roll motion. As shown in FIG. 3, the front wheel roll damping coefficient c _f is the portion of the damping coefficient in the roll direction that is handled by the front axle, and the rear wheel roll damping coefficient c _r is the portion of the above damping coefficient in the roll direction, as shown in FIG. 4. This is the portion of the damping coefficient in the roll direction that is handled by the rear shaft. Note that Figures 2 to 4 are models of the vehicle 1 as a pendulum (load transfer model); Figure 2 is a model viewed from the rear of the vehicle; Figure 3 is a model cut along the center line of the front axle; Figure 4 shows a model cut along the center line of the rear axle.

The roll angle acquisition unit 11 of this embodiment uses the model shown in FIG. 2 to estimate (calculate) the roll angle θ using the following equation 1. In Equation 1, m is the vehicle mass, h is the roll radius, I _x is the roll moment of inertia, k is the vehicle roll stiffness, and g is the gravitational acceleration, all of which are fixed values. Note that the roll damping coefficients c _f and _cr of the front and rear wheels are, for example, mapped in advance as constants for the roll angular velocity, and are obtained by applying the roll angular velocity to the map. Further, the roll angular velocity may be obtained, for example, by differentiating the estimated roll angle θ, or may be a sensor value. The vehicle roll stiffness k is the sum of the front wheel roll stiffness k _f for the front wheels 2F and the rear wheel roll stiffness k _r for the rear wheels 2R. Note that the roll rigidities k _f and k _r of the front and rear wheels are fixed values, and s is a Laplace operator.

The load transfer amount estimating unit 12 calculates the load transfer amount ΔW _{y_f} between the left and right wheels of the front wheel 2F (hereinafter referred to as the front wheel side load transfer amount ΔW _{y_f} ) and the load transfer amount ΔW _{y_r} (hereinafter referred to as “front wheel side load transfer amount ΔW y_f”) between the left and right wheels of the rear wheel 2R. The rear wheel side load movement amount ΔW _{y_r} ) is estimated. The front wheel side load movement amount ΔW _{y_f} is estimated based on the roll angle θ acquired by the roll angle acquisition unit 11, the lateral force Y _f of the front wheel 2F, the front wheel roll damping coefficient c _f , and the front wheel roll rigidity k _f be done. Similarly, the rear wheel side load movement amount ΔW _{y_r} is calculated by the roll angle θ acquired by the roll angle acquisition unit 11, the lateral force Y _r of the rear wheel 2R, the rear wheel roll damping coefficient _cr , and the rear wheel roll rigidity. It is estimated based on k _r .

Note that the lateral force Y _f of the front wheel 2F is the sum of the lateral force Y ₁ of the left front wheel 2FL and the lateral force Y ₂ of the right front wheel 2FR (Y _f =Y ₁ +Y ₂ ), and the lateral force Y of the rear wheel 2R is _r is the sum of the lateral force Y ₃ of the left rear wheel 2RL and the lateral force Y ₄ of the right rear wheel 2RR (Y _r =Y ₃ +Y ₄ ). As will be described later, it is preferable to use values estimated by the load movement amount estimating section 12 for the lateral forces Y _f and Y _r of the front and rear wheels 2F and 2R.

The load movement amount estimation unit 12 of this embodiment estimates both the front wheel side load movement amount ΔW _{y_f} and the rear wheel side load movement amount ΔW _{y_r} , but the control device 10 estimates the vertical load Z ₃ of the rear wheel 2R, When having the function of estimating Z ₄ (without having the function of estimating the vertical loads Z ₁ and Z ₂ of the front wheels 2F), the load movement amount estimation unit 12 estimates only the rear wheel side load movement amount ΔW _{y_r} . do it. In other words, the load movement amount estimating section 12 only needs to estimate at least one of the front wheel side load movement amount ΔW _{y_f} and the rear wheel side load movement amount ΔW _{y_r} .

The load movement amount estimating unit 12 of this embodiment uses the model shown in FIG. 3 to estimate the front wheel side load movement amount ΔW _{y_f} from the following equation 2, which is a balance equation of the moment acting around the roll center of the front wheel 2F. . Specifically, Equation 2 is solved for the front wheel side load movement amount ΔW _{y_f} , and the front wheel side load movement amount ΔW _{y_f} is estimated (calculated) using Laplace-transformed Equation 3. In

Equations

2 and 3, T _f is the front tread, and h _f is the roll center height (height from the ground to the roll center) of the front wheel 2F, both of which are fixed values. Furthermore, Z _{1_0} and Z _{2_0} in Equation 2 are vertical loads on the left and right front wheels 2FL and 2FR when the vehicle is stopped. These values Z _{1_0} and Z _{2_0} may be, for example, predetermined fixed values, or may be estimated values estimated from suspension stroke sensor values. Note that these values Z _{1_0} and Z _{2_0} do not necessarily have to be equal to each other.

The same applies to the rear wheel 2R. That is, the load movement amount estimating unit 12 uses the model of FIG. 4 to estimate the rear wheel side load movement amount ΔW _{y_r} from the following equation 4, which is a balance equation of the moment acting around the roll center of the rear wheel 2R. . Specifically, Equation 4 is solved for the rear wheel side load movement amount ΔW _{y_r} , and Laplace-transformed Equation 5 is used to estimate (calculate) the rear wheel side load movement amount ΔW _{y_r} . In equations 4 and 5, T _r is the rear tread, and h _r is the roll center height of the rear wheel 2R, both of which are fixed values. Furthermore, Z _{3_0} and Z _{4_0} in Equation 4 are vertical loads on the left and right rear wheels 2RL and 2RR when the vehicle is stopped, and are the same as on the front wheels.

As described above, the load movement amount estimating unit 12 of this embodiment estimates the lateral forces Y _f and Y _r of the front and rear wheels 2F and 2R. Specifically, based on the yaw rate r detected by the yaw rate sensor 21 and the lateral acceleration A _y detected by the lateral acceleration sensor 22, the lateral forces Y _f and Y _r of the front and rear wheels 2F and 2R are estimated. Then, when estimating the load movement amounts ΔW _{y_f} and ΔW _{y_r} described above, the estimated lateral forces Y _f and Y _r are used.

The load movement estimation unit 12 of this embodiment calculates each lateral force Y _f , Y _r of the front and rear wheels 2F, 2R using Equations 7 and 8 obtained by solving Equation 6 below for the lateral forces Y _f and Y _r . Estimate each. Note that this estimation is performed in the same calculation cycle as the estimation of the load movement amounts ΔW _{y_f} and ΔW _{y_r} described above.

In formulas 6 to 8, L _f is the distance in the longitudinal direction between the front axle and the center of gravity G, L _r is the distance in the longitudinal direction between the rear axle and the center of gravity G, and L is the wheel base (distance between the front and rear axles). is also a fixed value. Further, M _ADD is a yaw moment due to a difference in braking/driving force, and in this embodiment, is a control request value calculated by a control device other than the control device 10. However, the method for estimating the lateral forces Y _f and Y _r is not limited to this. For example, they may be estimated using a calculation cycle different from that for estimating the load movement amounts ΔW _{y_f} and ΔW _{y_r} , or instead of the yaw moment M _ADD . Or in addition, other parameters may be considered.

In addition, the load movement amount estimating unit 12 of this embodiment calculates the load movement amount ΔW _x (hereinafter referred to as the longitudinal load movement amount) of the longitudinal axis based on the longitudinal acceleration A _x detected by the longitudinal acceleration sensor 23 using the following equation ΔW _x ) is estimated. The longitudinal load movement amount ΔW _x is used in estimating the vertical loads Z ₁ to Z ₄ described below. Note that h _cg in Equation 9 is the height of the center of gravity.

The vertical load estimation unit 13 estimates the vertical loads Z ₁ to Z ₄ of each wheel 2 based on the front wheel side load movement amount ΔW _{y_f} and the rear wheel side load movement amount ΔW _{y_r} estimated by the load movement amount estimation unit 12. It is something to do. Specifically, the vertical loads Z 1 to Z 4 _of each wheel 2 are estimated by adding or subtracting the amount of load movement caused by the running state to the vertical loads Z _{1_0} to Z _{4_0} of each wheel 2 when the vehicle is stopped _. do. The vertical load estimating unit 13 of this embodiment also uses the longitudinal load movement amount ΔW _x estimated by the load movement amount estimating unit 12 to estimate each vertical load Z ₁ to Z ₄ according to equations 10 to 13 below. (calculate.

The vertical load estimation unit 13 of this embodiment estimates the vertical loads Z ₁ to Z ₄ of each wheel 2, but the control device 10 has a function of estimating the vertical loads Z ₃ and Z ₄ of the rear wheels 2R, for example. In the case (not having the function of estimating the vertical loads Z ₁ and Z ₂ on the front wheels 2F), the vertical load estimation unit 13 need only estimate the vertical loads Z ₃ and Z ₄ on the rear wheels 2R. In other words, the vertical load estimating unit 13 selects at least one of the wheels 2 (front wheel 2F and rear wheel 2R) for which the load movement amount is estimated based on the estimated load movement amount (at least one of ΔW _{y_f} and ΔW _{y_r} ). On the other hand, any method that estimates the vertical load on the other hand may be used.

The lateral force estimating unit 14 calculates each wheel based on the four vertical loads Z ₁ to Z ₄ estimated by the vertical load estimating unit 13, the lateral force Y _f of the front wheel 2F, and the lateral force Y _r of the rear wheel 2R. This is to estimate the lateral forces Y ₁ to Y ₄ of 2. In this embodiment, since the lateral forces Y _f and Y _r of the front and rear wheels 2F and 2R are estimated in the load movement amount estimating section 12, the lateral force estimating section 14 estimates the lateral forces Y ₁ to Y ₄ of each wheel 2. This estimation result is used when estimating . Specifically, each lateral force Y ₁ to Y ₄ is estimated (calculated) using equations 14 to 17 below.

The lateral force estimation unit 14 of this embodiment estimates the lateral forces Y ₁ to Y ₄ of each wheel 2, but the control device 10 has a function of estimating the vertical loads Z ₃ and Z ₄ of the rear wheels 2R, for example. In the case (without the function of estimating the vertical loads Z ₁ and Z ₂ of the front wheels 2F), the lateral force estimating unit 14 can estimate the lateral forces Y ₃ and Y ₄ of the rear wheels 2R. In other words, the lateral force estimating unit 14 calculates the vertical load of at least one wheel 2 (at least one of the front wheel 2F and the rear wheel 2R) estimated by the vertical load estimating unit 13, and the lateral force (lateral force) of at least one wheel 2. Each lateral force of at least one wheel 2 is estimated based on Y _f , Y _r ).

Note that this control device 10 executes processing up to estimating the vertical loads Z ₁ to Z ₄ and lateral forces Y ₁ to Y ₄ described above, but the values estimated here are used for various vehicle motion controls. Available. For example, by using it when estimating (calculating) the driving force and braking force of each wheel 2, it can be used to control an actuator (drive source or brake device). It can also be used to control other actuators (AFS, ARS, active suspension) and notification devices. These controls may be performed by the control device 10, or may be performed by a control device different from the control device 10.

[3. flowchart]
FIG. 5 shows an example of a flowchart executed in the control device 10 described above. This flowchart is executed, for example, at a predetermined calculation cycle when the main power source of the vehicle 1 is on or while the vehicle 1 is running. First, in step S1, information on various sensors 21 to 23 is acquired. In step S2, the roll angle θ is acquired (eg, estimated) by the roll angle acquisition unit 11. Subsequent steps S3 to S6 are performed by the load movement amount estimating section 12.

First, in step S3, each lateral force Y _f , Y _r of the front and rear wheels 2F, 2R is estimated, then in step S4 the front wheel side load movement amount ΔW _{y_f} is estimated, and in step S5 the rear wheel side load movement amount ΔW _{y_r} is estimated, and in step S6, the longitudinal load movement amount ΔW _x is estimated. Then, in step S7, the vertical load estimation section 13 estimates four vertical loads Z ₁ to Z ₄ , and in step S8, the lateral force estimation section 14 estimates four lateral forces Y ₁ to Y ₄ . Return the flowchart.

[4. effect]
According to the control device 10 described above, the vertical load on at least one of the wheels 2 of the front wheels 2F and the rear wheels 2R is detected using general-purpose detection means that are standard equipment on the vehicle 1, such as the yaw rate sensor 21 and the lateral acceleration sensor 22. Z ₁ to Z ₄ can be estimated. In this way, in a vehicle that does not require advanced vehicle body posture control including roll, pitch, and bounce, it is possible to reduce the vertical load Z ₁ to at least one of the front wheels 2F and rear wheels 2R using a relatively simple method. Since Z ₄ can be estimated, the control configuration can be simplified, contributing to cost reduction and improved versatility. For example, in the case of a vehicle 1 in which the left and right driving force of only the rear wheel 2R can be independently controlled among the front and rear wheels 2F and 2R, the vertical loads Z ₃ and Z ₄ of the rear wheel 2R and the amount of rear wheel side load movement ΔW _{y_r} are determined. If possible, the controllability of the vehicle 1 can be improved.

In the above control device 10, the load movement amount ΔW _{y_f} , ΔW _{y_r} of the front and rear wheels 2F, 2R is determined based on the detected value of the yaw rate r and the lateral acceleration A _y of each lateral force Y _f of the front and rear wheels 2F, 2R. , Y _r . Thereby, the accuracy of estimating the vertical loads Z ₁ to Z ₄ can be improved.
Further, in the above control device 10, the longitudinal load movement amount ΔW _x is estimated based on the longitudinal acceleration A _x detected by the longitudinal acceleration sensor 23, which is the longitudinal acceleration detection means, and this longitudinal load movement amount ΔW _x is used. Since the vertical load is estimated by

According to the control device 10 described above, in addition to the estimated vertical loads Z ₁ -Z ₄ , each lateral force Y ₁ -Y ₄ of the wheel 2 is also estimated based on the estimated vertical loads Z ₁ -Z ₄ . In this way, by estimating the force in the left-right direction and the vertical direction of each wheel 2, it becomes easier to utilize it for various vehicle motion controls.
For example, if it is utilized for spin behavior suppression control, which is one type of vehicle motion control, it becomes possible to appropriately set the braking/driving force of each wheel 2, and it is possible to effectively suppress tire skidding.

[5. others]
The configuration of the control device 10 described above is an example, and is not limited to the configuration described above.

Equations

1, 3, 5, 7 to 16 used for estimation by the control device 10 above are examples, and are not limited to the above equations. For example, the vertical load estimation unit 13 described above uses the longitudinal load movement amount ΔW _x estimated by the load movement estimation unit 12 when estimating the vertical loads Z ₁ to Z ₄ . The amount may be omitted or a preset (estimated) value may be used.

Furthermore, the configuration of the vehicle 1 to which the control device 10 is applied is also one example, and is not limited to the above-mentioned configuration. For example, if the vehicle 1 is equipped with an active stability control (ASC), the ASC may be activated according to information estimated by the control device 10 described above. Further, the type of actuator that is controlled using the estimation result of the control device 10 mounted on the vehicle 1 is not particularly limited.

1 Vehicle 2 Wheel 2F Front wheel 2FL Left front wheel (front wheel, wheel)
2FR right front wheel (front wheel, wheel)
2R Rear wheel 2RL Left rear wheel (rear wheel, wheel)
2RR Right rear wheel (rear wheel, wheel)
10 Control device 11 Roll angle acquisition unit 12 Load movement amount estimation unit 13 Vertical load estimation unit 14 Lateral force estimation unit 21 Yaw rate sensor 22 Lateral acceleration sensor 23 Longitudinal acceleration sensor A _x longitudinal acceleration A _y lateral acceleration c Vehicle roll damping coefficient c _f Front wheel roll damping coefficient c _r Rear wheel roll damping coefficient G Center of gravity g Gravity acceleration h Roll radius h _f Front wheel roll center height h _r Rear wheel roll center height I _x Roll moment of inertia k Vehicle roll stiffness k _f Front wheel roll stiffness k _r Rear wheel roll stiffness L Wheelbase (distance between front and rear axles)
L _f Longitudinal distance between the front axle and the center of gravity L _r Longitudinal distance between the rear axle and the center of gravity m Vehicle mass M Yaw moment due to _ADD braking/driving force difference r Yaw rate T _f Front tread T _r Rear tread ΔW _x Longitudinal load Amount of movement (amount of load movement on the front and rear axes)
ΔW _{y_f} Front wheel side load transfer amount (load transfer amount between the left and right front wheels)
ΔW _{y_r} Rear wheel side load transfer amount (load transfer amount between left and right rear wheels)
Y ₁ Lateral force on the left front wheel Y ₂ Lateral force on the right front wheel Y ₃ Lateral force on the left rear wheel Y ₄ Lateral force on the right rear wheel Y _f Lateral force on the front wheel Y _r Lateral force on the rear wheel Z ₁ Vertical load on the left front wheel Z ₂ Vertical load on the right front wheel Z ₃ Vertical load on the left rear wheel Z ₄ Vertical load on the right rear wheel θ Roll angle

Claims

The vehicle control device is provided with a yaw rate detection means for detecting a yaw rate of the vehicle, and a lateral acceleration detection means for detecting the lateral acceleration of the vehicle,
a roll angle acquisition unit that acquires a roll angle of the vehicle;
A load transfer amount between the left and right wheels of the front wheels based on the acquired roll angle, the lateral force of the front wheels, the front wheel roll damping coefficient regarding the front wheels, and the front wheel roll stiffness regarding the front wheels, and the acquired roll angle. and a load transfer amount for estimating at least one of the load transfer amount between the left and right wheels of the rear wheel based on the lateral force of the rear wheel, the rear wheel roll damping coefficient regarding the rear wheel, and the rear wheel roll stiffness regarding the rear wheel. Estimating section;
A vertical load estimating unit that estimates each vertical load of at least one of the front wheels and the rear wheels for which the load movement amount has been estimated, based on the estimated load movement amount. A vehicle control device.
The load movement amount estimation unit is characterized in that, when estimating the load movement amount, the lateral force of the at least one wheel is estimated based on the detected yaw rate and the detected lateral acceleration. The vehicle control device according to claim 1.
The vehicle is provided with longitudinal acceleration detection means for detecting longitudinal acceleration of the vehicle,
The load movement amount estimation unit estimates the load movement amount of the longitudinal axis based on the detected longitudinal acceleration,
3. The vehicle control device according to claim 1, wherein the vertical load estimator uses the estimated load movement amount of the longitudinal axis when estimating the vertical load.
a lateral force estimation unit that estimates a lateral force of each of the at least one wheel based on the vertical load of the at least one wheel estimated by the vertical load estimation unit and the lateral force of the at least one wheel; 3. The vehicle control device according to claim 1, further comprising:
a lateral force estimation unit that estimates a lateral force of each of the at least one wheel based on the vertical load of the at least one wheel estimated by the vertical load estimation unit and the lateral force of the at least one wheel; 4. The vehicle control device according to claim 3, further comprising: