Posture control device

Abstract

To provide a posture control device that is able to bring a pitch state during regenerative cooperative control of an xEV vehicle close to that of an ICE vehicle having the same suspension device.SOLUTION: In a posture control device, a control device (a braking control unit) compares a front axle value ΔA1, which is a differential between a tangent tan (βf) of a friction-side anti-dive angle βf and a tangent tan (βf_in) of a regeneration-side anti-dive angle βf_in of a suspension device, with a rear axle value ΔA2, which is a differential between a tangent tan (βr) of a friction-side anti-lift angle βr and a tangent tan (βr_in) of a regeneration-side anti-lift angle βr_in. The control device makes a share proportion of a frictional braking force Fmf or a frictional braking force Fmr in one shaft having a larger value of the front shaft value ΔA1 and the rear shaft value ΔA2, larger than that in the other shaft; and makes a share proportion of a regenerative braking force Fkf or a regenerative braking force Fkr in the other shaft larger than that in the one shaft.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an attitude control device.

Background Art

[0002] Conventionally, a technique related to regenerative cooperative control for applying regenerative braking force and frictional braking force to a vehicle using a regenerative braking device and a frictional braking device has been known. For example, Patent Document 1 describes a vehicle control device that changes the ratio of regenerative braking force and frictional braking force when a braking operation is performed by a driver and vehicle motion control is performed. In this vehicle control device, for example, when the vehicle is turning and braking, by reducing the ratio of the regenerative braking force in the wheels on the inner side of the turn, it is possible to prevent the in-wheel motor from exceeding the control range. Further, in this vehicle control device, when the vehicle is turning and braking, by reducing the ratio of the frictional braking force in the wheels on the outer side of the turn, the amount of power recovered is increased and the loss due to friction is reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, a mixed platform in which various mechanisms such as a suspension device are the same may be adopted for a general ICE (Internal combustion engine) vehicle having an internal combustion engine as a drive source and an xEV vehicle including an electrified power source such as an electric vehicle or a hybrid vehicle. However, since the magnitude of the anti-force acting on the vehicle during braking is different between an ICE vehicle and an xEV vehicle, when a suspension device adapted to an ICE vehicle is adopted for an xEV vehicle, the pitch state during vehicle braking by regenerative cooperative control may change, which may give the driver a sense of discomfort.

[0005] The present invention has been made in view of such problems, and an object thereof is to provide an attitude control device capable of bringing the pitch state during braking closer to that of an ICE vehicle having the same suspension device in an xEV vehicle that performs braking by regenerative cooperative control.

Means for Solving the Problems

[0006] In order to achieve the above object, the attitude control device of the present invention is an attitude control device provided in a vehicle including an electrified power source, in which front and rear left and right wheels are suspended by a suspension device having anti-dive and anti-lift geometries, and includes a friction braking device that applies frictional braking force to a front axle to which the front wheels are connected and a rear axle to which the rear wheels are connected, respectively, a regenerative braking device that applies regenerative braking force to the front axle and the rear axle, respectively, and a braking control unit that controls the friction braking device and the regenerative braking device so as to cooperatively output a required braking force required for braking of the vehicle with the regenerative braking force and the frictional braking force. The braking control unit compares a front axle value that is a difference between the tangent of the friction-side anti-dive angle and the tangent of the regenerative-side anti-dive angle of the suspension device, and a rear axle value that is a difference between the tangent of the friction-side anti-lift angle and the tangent of the regenerative-side anti-lift angle, and increases the sharing ratio of the frictional braking force on the axle with the larger value of the front axle value and the rear axle value compared to the other axle, and increases the sharing ratio of the regenerative braking force on the other axle compared to the one axle.

Effects of the Invention

[0007] According to the attitude control device of the present invention, in an xEV vehicle that performs braking by regenerative cooperative control, it is possible to bring the pitch state during braking closer to that of an ICE vehicle having the same suspension device.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a vehicle equipped with a posture control device according to the embodiment. The vehicle 1 transmits the power from the front motor 10f as a traveling power source to the left and right front wheels 2f (wheels), and at the same time transmits the power from the rear motor 10r as a traveling power source to the left and right rear wheels 2r (wheels) and travels. It is a four-wheel drive electric vehicle. Note that the vehicle 1 may be an xEV vehicle including an electrified power source such as a BEV (Battery Electric Vehicle), HEV (Hybrid Electric Vehicle), PHEV / PHV (Plug-in Hybrid Electric Vehicle / Plug-in Hybrid Vehicle), FCEV / FCV (Fuel Cell Electric Vehicle / Fuel Cell Vehicle).

[0010] The front motor 10f outputs driving force to the left and right front wheels 2f via a transaxle 12f including a transmission and a differential gear, and left and right front axles 13f. The rear motor 10r outputs driving force to the left and right rear wheels 2r via a transaxle 12r including a transmission and a differential gear, and left and right rear axles 13r. The vehicle 1 is equipped with a battery 14 as a power source configured as a secondary battery such as a lithium-ion battery, and the power from the battery 14 is supplied to the front motor 10f and the rear motor 10r via a power conversion device such as an inverter (not shown). The front motor 10f and the rear motor 10r are driven and controlled by a control device 16 (braking control unit).

[0011] Also, the vehicle 1 is provided with a braking device that applies braking force to the front wheels 2f and the rear wheels 2r. The braking device includes a regenerative braking device 20 and a friction braking device 30. The control device 16, the regenerative braking device 20, and the friction braking device 30 constitute the attitude control device 40 of the present embodiment.

[0012] The regenerative braking device 20 is configured to include the front motor 10f and the rear motor 10r, the battery 14, and a power conversion device such as an inverter (not shown). The front motor 10f and the rear motor 10r are forcibly driven by the rotational force of the front wheels 2f and the rear wheels 2r during decelerated driving with the accelerator off of the vehicle 1 to generate regenerative power, and apply regenerative braking force to the front wheels 2f and the rear wheels 2r. The regenerative power generated by the front motor 10f and the rear motor 10r is supplied to the battery 14.

[0013] The friction braking device 30 is a disc brake device that applies frictional braking force to each of the front axles 13f and the rear axles 13r (each of the front wheels 2f and the rear wheels 2r) by the frictional force generated by pressing a brake pad 34 driven by an actuator (not shown) against a disc rotor 32 provided corresponding to each of the front axles 13f and the rear axles 13r (each of the front wheels 2f and the rear wheels 2r). Note that the actuator may be either hydraulic or electric.

[0014] The control device 16 is configured to include an input / output device, a storage device (such as ROM, RAM, non-volatile RAM, etc.), a central processing unit (CPU), etc., and performs comprehensive control of the vehicle 1. The control device 16 inputs detection amounts detected by various sensors (not shown) such as accelerator opening, brake stroke, vehicle speed, and wheel speed, and various operation information. Based on the various input detection amounts and various operation information, the control device 16 calculates information necessary for controlling the vehicle 1, such as the required driving force and the required braking force required for the running of the vehicle 1, and controls various devices of the vehicle 1 based on the calculated information.

[0015] For example, the control device 16 performs regenerative cooperative control in which the regenerative braking device 20 and the friction braking device 30 are driven and controlled to output the required braking force required for braking the vehicle 1 in cooperation with the regenerative braking force and the friction braking force. Specifically, the control device 16 calculates the required braking force Fb according to the amount of brake depression by the driver, and based on the calculated required braking force Fb, the regenerative braking force Fkf applied from the front motor 10f to the front axle 13f (front wheels 2f), the Fkr applied from the rear motor 10r to the rear axle 13r (rear wheels 2r), the friction braking force Fmf applied from each friction braking device 30 to the front axle 13f (front wheels 2f), and the friction braking force Fmr applied to the rear axle 13r (rear wheels 2r) are set (see Figure 2).

[0016] The control device 16 sets the regeneration ratio k, the friction ratio m, the front ratio f, and the rear ratio r while satisfying the required braking force Fb with the sum of the regenerative braking forces Fkf, Fkr and the frictional braking forces Fmf, Fmr as shown in the following formula (1). The regeneration ratio k, the friction ratio m, the front ratio f, and the rear ratio r are represented by the following formulas (2) to (5). The regeneration ratio k and the friction ratio m are the distribution ratios between the regenerative braking forces Fkf, Fkr and the frictional braking forces Fmf, Fmr, and are set between 0 and 1 such that their sum becomes 1. Also, the front ratio f and the rear ratio r are the distribution ratios between the braking forces (Fkf, Fmf) applied to the front wheels 2f and the braking forces (Fkr, Fmr) applied to the rear wheels 2r, and are set between 0 and 1 such that their sum becomes 1. In the regenerative cooperative control, for example, the regenerative braking forces Fkf, Fkr are output within the range of the upper limit value of the regenerative power generation amount according to the required braking force Fb, and the shortage of the regenerative braking forces Fkf, Fkr with respect to the required braking force Fb is output as the frictional braking forces Fmf, Fmr. The upper limit value of the regenerative power generation amount is set according to the state of charge (SOC) and temperature of the battery 14, etc.

[0017] Fb = Fkf + Fkr + Fmf + Fmr …(1) k = (Fkf + Fkr) / Fb …(2) m = (Fmf + Fmr) / Fb …(3) f = (Fkf + Fmf) / Fb …(4) r = (Fkr + Fmr) / Fb …(5)

[0018] FIG. 2 is an explanatory diagram schematically showing the anti-angles and anti-forces of the vehicle 1. Between each wheel 2f, 2r of the vehicle 1 and the vehicle body, there is a suspension device 11 having anti-dive and anti-lift geometry and suspending each wheel 2f, 2r with respect to the vehicle body. In the following description, the inboard portion above the suspension device 11 of the vehicle 1 is appropriately referred to as the "above-spring portion", and the outboard portion located below the suspension device 11 is referred to as the "below-spring portion". An anti-force corresponding to the frictional braking forces Fmf, Fmr which are braking forces acting on the below-spring portion, and an anti-force corresponding to the regenerative braking forces Fkf, Fkr which are braking forces acting on the above-spring portion act according to each anti-angle.

[0019] Each anti-angle is determined by the geometry of the suspension device 11 and includes a frictional-side anti-dive angle βf, a frictional-side anti-lift angle βr, a regenerative-side anti-dive angle βf_in, and a regenerative-side anti-lift angle βr_in. The frictional-side anti-dive angle βf is the anti-nose dive angle in a general suspension geometry, and the frictional-side anti-lift angle βr is the anti-tail lift angle. Also, the regenerative-side anti-dive angle βf_in corresponds to the anti-nose up angle that applies an anti-nose up force during vehicle driving in a general suspension geometry, and the regenerative-side anti-lift angle βr_in corresponds to the anti-squat angle that applies an anti-squat force during vehicle driving.

[0020] When frictional braking forces Fmf and Fmr are applied to the vehicle 1, an anti-dive force Famf as the vertically upward component of the frictional braking force Fmf acts on the front side of the vehicle 1 according to the frictional anti-dive angle βf, and an anti-lift force Famr as the vertically downward component of the frictional braking force Fmr acts on the rear side of the vehicle 1 according to the frictional anti-lift angle βr. Similarly, when regenerative braking forces Fkf and Fkr are applied to the vehicle 1, an anti-dive force Fakf as the vertically upward component of the regenerative braking force Fkf acts on the front side of the vehicle 1 according to the regenerative anti-dive angle βf_in, and an anti-lift force Fakr as the vertically downward component of the regenerative braking force Fkr acts on the rear side of the vehicle 1 according to the regenerative anti-lift angle βr_in. These respective anti-forces Famf, Famr, Fakf, and Fakr are represented by the following equations (6) to (9).

[0021] Famf = Fmf·tan(βf) …(6) Famr = Fmr·tan(βr) …(7) Fakf = Fkf·tan(βf_in) …(8) Fakr = Fkr·tan(βr_in) …(9)

[0022] Next, the pitching state during braking when the vehicle 1 is moving forward will be described. FIG. 3 is an explanatory diagram showing an example of the pitching state during braking of the vehicle 1, and FIG. 4 is an explanatory diagram showing another example of the pitching state during braking of the vehicle 1. As shown in the figures, when the vehicle 1 is braking, an inertial force in the forward direction acts on the center of gravity CG, causing a pitching change in which the front part of the vehicle body sinks and the rear part rises. In FIG. 3, it can be seen that the rear part is rising more than in FIG. 4, that is, the suspension device 11 on the rear wheel 2r side is extended. When the vehicle 1 is braking, as shown in FIG. 4, it is preferable that the suspension device 11 on the front wheel 2f side of the vehicle 1 slightly contracts and the suspension device 11 on the rear wheel 2r side does not extend as much as possible (the posture of nose dive in which the front part of the vehicle 1 slightly sinks). This is because it is considered that the driver can easily recognize the deceleration generated in the vehicle body during braking of the vehicle 1, and as a result, it becomes easier to perform the braking operation. In order to satisfy this requirement, the values of the anti-angles βf, βr, βf_in, and βr_in are set.

[0023] Here, a mixed platform in which various mechanisms such as the suspension device 11 are the same may be adopted for a general ICE vehicle having an internal combustion engine as a driving source for traveling and an xEV vehicle including an electrified power source. However, since the ICE vehicle does not have a regenerative braking device 20, no regenerative braking force acts during braking. Although a braking force due to engine braking acts on the sprung part of the ICE vehicle, the braking force due to engine braking is smaller than the regenerative braking force. That is, in the ICE vehicle, the frictional braking forces Fmf and Fmr are the main braking forces, and the anti-forces during braking are also mainly the anti-dive force Famf or the anti-lift force Famr. Therefore, in the ICE vehicle, each anti-angle is set so that the pitching state shown in FIG. 4 occurs according to the action of the anti-dive force Famf or the anti-lift force Famr.

[0024] On the other hand, in the regenerative cooperative control of an xEV vehicle, braking forces with different tendencies often act, such as when the regenerative braking forces Fkf and Fkr are set to be large and the frictional braking forces Fmf and Fmr are set to be small, which is different from an ICE vehicle. Therefore, when a suspension device 11 having a geometry adapted to an ICE vehicle is adopted in an xEV vehicle, as a result, it becomes difficult to generate the pitch state shown in FIG. 4 during braking, and there is a possibility of giving the driver a sense of discomfort. Thus, in the attitude control device 40 of the present embodiment, in an xEV vehicle adopting a mixed platform, in order to generate a pitch state as close as possible to that of an ICE vehicle during braking, the following tendency setting process for the regenerative friction sharing ratio of the braking force is executed.

[0025] FIG. 5 is a flowchart showing an example of the tendency setting process for the regenerative friction sharing ratio. The process shown in FIG. 5 is repeatedly executed by the control device 16 every unit time during the running of the vehicle 1. However, the processes in steps S1 to S3 are executed when the control device 16 acquires information indicating that a mixed platform in which the vehicle 1 has the same suspension device 11 as another ICE vehicle is adopted, and it is sufficient to store the determination result of step S3. That is, the process in FIG. 5 may be such that the processes in steps S4 and S5 are repeatedly executed every unit time according to the stored determination result of step S3.

[0026] The control device 16 first calculates a front axle value ΔA1, which is the difference between the tangent tan(βf) of the friction-side anti-dive angle βf and the tangent tan(βf_in) of the regenerative-side anti-dive angle βf_in of the suspension device 11, as shown in the following formula (10) (step S1). Next, the control device 16 calculates a rear axle value ΔA2, which is the difference between the tangent tan(βr) of the friction-side anti-lift angle βr and the tangent tan(βr_in) of the regenerative-side anti-lift angle βr_in of the suspension device 11, as shown in the following formula (11) (step S2). It is assumed that the tangent tan(βf) is larger than the tangent tan(βf_in), and the tangent tan(βr) is larger than the tangent tan(βr_in).

[0027] ΔA1 = tan(βf) - tan(βf_in) …(10) ΔA2 = tan(βr) - tan(βr_in) …(11)

[0028] Next, the control device 16 compares which of the front axle value ΔA1 and the rear axle value ΔA2 is larger (step S3). When the control device 16 determines in step S3 that the front axle value ΔA1 is larger than the rear axle value ΔA2, it proceeds to step S4, sets the friction sharing ratio of the front axle 13f to be larger than that of the other axle (rear axle 13r), and executes this routine again. On the other hand, when the control device 16 determines in step S3 that the rear axle value ΔA2 is larger than the front axle value ΔA1, it proceeds to step S5, sets the friction sharing ratio of the rear axle 13r to be larger than that of the other axle (front axle 13f), and executes this routine again. As described above, the processes of steps S1 to S3 do not necessarily need to be repeatedly executed, and the processes of steps S4 and S5 may be repeatedly executed every unit time. Also, when the front axle value ΔA1 and the rear axle value ΔA2 are the same value, the control device 16 may execute either of the processes of steps S4 and S5.

[0029] The processes of steps S4 and S5 will be specifically described. FIG. 6 is an explanatory diagram showing an example in which the tendency of the regenerative friction sharing ratio for each axle is changed. FIG. 6 shows an example of the case where the friction sharing ratio of the rear axle 13r is increased (step S5 in FIG. 5). Now, the regenerative braking forces Fkf, Fkr and the friction braking forces Fmf, Fmr shown on the left side in the figure show an example in the regenerative cooperative control before the change, that is, when not considering the mixed platform. In the example shown before the change, the sharing ratio between the regenerative braking force Fkf acting on the front axle 13f and the friction braking force Fmf, and the sharing ratio between the regenerative braking force Fkr acting on the rear axle 13r and the friction braking force Fmr are the same with the above-described regenerative ratio k and friction ratio m.

[0030] On the one hand, the regenerative braking forces Fkf and Fkr and the frictional braking forces Fmf and Fmr shown on the right side in the figure illustrate an example when the sharing ratios are changed by the tendency setting process. In this case, as shown in the figure, the frictional braking force Fmr of the rear axle 13r is set to be larger than that of the other axle (front axle 13f), and the regenerative braking force Fkr is set to be smaller than that of the other axle (front axle 13f). Also, the regenerative braking force Fkf of the front axle 13f is set to be larger than that of the other axle (rear axle 13r), and the frictional braking force Fmf is set to be smaller than that of the other axle (rear axle 13r) (here, the frictional braking force Fmf has a value of 0). In this tendency setting process, first, the required braking force Fb is maintained. Also, the braking force sharing ratio between the front axle 13f and the rear axle 13r, that is, the above-described front ratio f and rear ratio r are also maintained. Moreover, it is more preferable that the total amount of the frictional braking forces Fmf and Fmr and the total amount of the regenerative braking forces Fkf and Fkr (the overall regeneration ratio k and frictional ratio m) are maintained. That is, when setting the frictional sharing ratio of the rear axle 13r to be larger than that of the front axle 13f, it is more preferable that the sharing ratios are set so that the decrease amount of the regenerative braking force Fkr at the rear axle 13r is covered by the increase amount of the regenerative braking force Fkf of the front axle 13f.

[0031] And by increasing the frictional sharing ratio of the rear axle 13r (increasing the frictional braking force Fmr) as described above, among the anti-forces, the anti-lift force Famr acts more strongly on the vehicle 1. During braking of an ICE vehicle, as described above, the pitch state is determined by the action of the anti-dive force Famf or anti-lift force Famr due to the frictional braking forces Fmf and Fmr. In other words, if the anti-dive force Famf due to the frictional braking force Fmf or the anti-lift force Famr due to the frictional braking force Fmr is made to act more strongly, in the xEv vehicle equipped with the same suspension device 11 as the ICE vehicle, the pitch state during braking can be made closer to that of the ICE vehicle.

[0032] Therefore, according to the comparison result in step S3, select the axis with the larger value between the front axle value ΔA1 and the rear axle value ΔA2, that is, the axis on which the anti-dive force Famf or the anti-lift force Famr is more likely to act effectively by increasing the friction sharing ratio, and set the friction sharing ratio on the axis to be large. Thereby, it becomes easier to realize a pitch state close to the ICE vehicle during braking. If it is determined in step S3 that the front axle value ΔA1 is larger than the rear axle value ΔA2, the friction sharing ratio of the front axle 13f may be set large so that the anti-dive force Famf due to the friction braking force Fmf acts greatly.

[0033] Each of the above sharing ratios may be appropriately set based on experiments, analysis, etc. so as to obtain a pitch state as close as possible to the ICE vehicle. By setting the tendency of the regenerative friction sharing ratio as described above, it can also be used in the vehicle 1 without changing the regenerative cooperative control program itself used in a normal xEV vehicle that does not adopt a mixed platform.

[0034] However, when the upper limit value of the regenerative power generation amount is limited, the control device 16 gives priority to the limit over the change of the sharing ratio. That is, as described above, the upper limit value of the regenerative power generation amount is set according to the charge rate (SOC: State Of Charge) and temperature of the battery 14. When this upper limit value is limited, there may also be a limit to the regenerative braking forces Fkf and Fkr that can be increased at either the front axle 13f or the rear axle 13r. Thus, when the regenerative braking forces Fkf and Fkr are limited due to the limitation of the upper limit value of the regenerative power generation amount, the control device 16 sets the friction sharing ratio and the regenerative sharing ratio as needed so that the regenerative braking forces Fkf and Fkr are within the range of the limit. Thereby, it is possible to prevent the regenerative power generation amount from exceeding the upper limit value and ensure safety.

[0035] As described above, in the attitude control device 40 of the embodiment, the control device 16 (braking control unit) compares the front axle value ΔA1, which is the difference between the tangent tan(βf) of the friction side anti-dive angle βf of the suspension device 11 and the tangent tan(βf_in) of the regenerative side anti-dive angle βf_in, with the rear axle value ΔA2, which is the difference between the tangent tan(βr) of the friction side anti-lift angle βr and the tangent tan(βr_in) of the regenerative side anti-lift angle βr_in. The control device 16 increases the sharing ratio of the friction braking force Fmf or Fmr on the axle with the larger value between the front axle value ΔA1 and the rear axle value ΔA2 compared to the other axle, and increases the sharing ratio of the regenerative braking force Fkf or Fkr on the other axle compared to the one axle.

[0036] With this configuration, by setting a larger friction sharing ratio on the axle where the anti-dive force Famf or the anti-lift force Famr is more likely to act effectively, the anti-dive force Famf or the anti-lift force Famr can be made to act more strongly. As a result, in the vehicle 1, which is an xEv vehicle employing the same suspension device 11 as an ICE vehicle, it becomes possible to mainly apply the anti-dive force Famf or the anti-lift force Famr to the vehicle 1 in the same manner as the ICE vehicle. Also, by making the sharing ratio of the regenerative braking force Fkf or Fkr on the other axle larger than that of the one axle with the increased friction sharing ratio, a decrease in the regenerative power generation amount can be suppressed. Therefore, according to the attitude control device 40 of the embodiment, in the vehicle 1, which is an xEV vehicle performing braking by regenerative cooperative control, it becomes possible to make the pitch state during braking closer to that of an ICE vehicle having the same suspension device 11.

[0037] Also, the control device 16 changes the sharing ratio while maintaining the total amounts of the friction braking forces Fmf, Fmr and the total amounts of the regenerative braking forces Fkf, Fkr. With this configuration, the decrease amount of the regenerative braking forces Fkf, Fkr on one axle can be covered by the increase amount of the regenerative braking forces Fkf, Fkr on the other axle, and the regenerative power generation amount can be more reliably ensured.

[0038] Further, when the upper limit value of the regenerative power generation amount is restricted, the control device 16 prioritizes such restriction over the change of the above-described sharing ratio. With this configuration, as described above, it is possible to ensure safety by preventing the regenerative power generation amount from exceeding the restricted upper limit value.

[0039] Although the description of the embodiment ends here, aspects of the present invention are not limited to this embodiment. For example, in this embodiment, while maintaining the total amount of the frictional braking forces Fmf and Fmr and the total amount of the regenerative braking forces Fkf and Fkr, the regenerative friction sharing ratio is changed. However, the total amount does not necessarily have to be maintained completely. Further, when the upper limit value of the regenerative power generation amount is restricted, instead of changing the sharing ratio itself, the braking force may be applied to the vehicle 1 according to the program of the normal regenerative cooperative control.

Explanation of Reference Numerals

[0040] 1 Vehicle 2f Front wheel (wheel) 2r Rear wheel (wheel) 11 Suspension device 13f Front axle 13r Rear axle 16 Control device 20 Regenerative braking device 30 Frictional braking device 40 Attitude control device Fkf, Fkr Regenerative braking force Fmf, Fmr Frictional braking force βf Frictional side anti-dive angle βf_in Regenerative side anti-dive angle βr Frictional side anti-lift angle βr_in Regenerative side anti-lift angle ΔA1 Front axle value ΔA2 Rear axle value

Claims

1. A posture control device provided in a vehicle including an electrified power source, in which front and rear wheels are suspended by a suspension device having anti-dive and anti-lift geometries, the posture control device comprising: a friction braking device that applies frictional braking force to a front axle to which front wheels are connected and a rear axle to which rear wheels are connected, respectively; a regenerative braking device that applies regenerative braking force to the front axle and the rear axle, respectively; a braking control unit that controls the friction braking device and the regenerative braking device so as to cooperatively output a required braking force required for braking of the vehicle with the regenerative braking force and the frictional braking force; and the braking control unit: compares a front axle value, which is a difference between the tangent of the friction-side anti-dive angle and the tangent of the regenerative-side anti-dive angle of the suspension device, and a rear axle value, which is a difference between the tangent of the friction-side anti-lift angle and the tangent of the regenerative-side anti-lift angle; characterized in that a sharing ratio of the frictional braking force on the axle with the larger value of the front axle value and the rear axle value is made larger than that of the other axle, and a sharing ratio of the regenerative braking force on the other axle is made larger than that of the one axle.

2. The posture control device according to claim 1, characterized in that the braking control unit changes the sharing ratio while maintaining the total amount of the frictional braking force and the total amount of the regenerative braking force.

3. The posture control device according to claim 1 or claim 2, characterized in that when an upper limit value of the regenerative power generation amount is limited, the braking control unit gives priority to the limitation over the change of the sharing ratio.

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