1. An electric suspension device is provided with an actuator which is provided between a vehicle body and a wheel of a vehicle and generates a damping force for damping vibration of the vehicle body,

the electric suspension device is characterized by comprising:

an information acquisition unit that acquires information on the sprung velocity, pitch rate, and roll rate of the vehicle;

a bounce target value calculation unit that calculates a bounce target value for controlling a bounce attitude of the vehicle based on the sprung velocity;

a pitch target value calculation unit that calculates a pitch target value for controlling the pitch attitude of the vehicle based on the pitch rate;

a roll target value calculation unit that calculates a roll target value for roll attitude control of the vehicle based on the roll rate; and

and a drive control unit that performs drive control of the actuator using a control target load obtained based on a sum of the bounce target value, the pitch target value, and the roll target value.

2. The electric suspension device according to claim 1,

the pitch target value calculation unit corrects a pitch target value as a result of the calculation based on the information of the sprung mass velocity,

the roll target value calculation unit corrects the roll target value as a result of the calculation based on the information on the sprung velocity,

the drive control unit performs drive control of the actuator using a control target load obtained based on a total value of the bounce target value and the corrected pitch target value and the corrected roll target value.

3. An electric suspension device is provided with an actuator which is provided between a vehicle body and a wheel of a vehicle and generates a damping force for damping vibration of the vehicle body,

the electric suspension device is characterized by comprising:

an information acquisition unit that acquires the sprung velocity and the angular wheel sprung velocity difference of the vehicle, respectively;

a bounce target value calculation unit that calculates a bounce target value for controlling a bounce attitude of the vehicle based on the sprung velocity;

a pitch target value calculation unit that calculates a pitch target value for controlling the pitch attitude of the vehicle based on the diagonal wheel sprung velocity difference;

a roll target value calculation unit that calculates a roll target value for roll attitude control of the vehicle based on the diagonal wheel sprung velocity difference; and

and a drive control unit that performs drive control of the actuator using a control target load obtained based on a sum of the bounce target value, the pitch target value, and the roll target value.

4. The electric suspension device according to claim 3,

the information acquisition unit further acquires information on a pitch rate and a roll rate,

the pitch target value calculation unit corrects the pitch target value as a calculation result based on information that gives priority to the order of the pitch rate and the roll rate,

the roll target value calculation unit corrects the roll target value as a calculation result based on information that gives priority to the order of the pitch rate and the roll rate,

the drive control unit performs drive control of the actuator using a control target load obtained based on a total value of the bounce target value and the corrected pitch target value and the corrected roll target value.

5. The electric suspension device according to claim 3,

the information acquisition portion further acquires information of a vehicle speed of the vehicle,

the pitch target value calculation unit corrects the pitch target value as a result of the calculation based on the vehicle speed so that the value becomes larger as the vehicle speed becomes higher,

the roll target value calculation unit corrects the roll target value as a result of the calculation based on the vehicle speed so that the value thereof becomes larger as the vehicle speed becomes higher,

the drive control unit performs drive control of the actuator using a control target load obtained based on a total value of the bounce target value and the corrected pitch target value and the corrected roll target value.

Background

Conventionally, there is known an electric suspension device provided with an actuator that is provided between a vehicle body and a wheel of a vehicle and generates a damping force for damping vibration of the vehicle body (see patent document 1).

The electric suspension device of patent document 1 includes: a basic input amount calculation means that calculates a basic input amount of the vehicle based on a wheel speed variation amount detected by the wheel speed sensor; 1 st target current setting means for setting a 1 st target current based on the basic input amount; a 2 nd target current setting means for setting a 2 nd target current based on the vehicle body acceleration detected by the acceleration sensor; and a control means for controlling the damper (actuator) based on the 1 st target current when a vehicle behavior control device for controlling the behavior of the vehicle is not operating, and controlling the damper (actuator) based on the 2 nd target current when the vehicle behavior control device is operating.

According to the electric suspension device of patent document 1, the damping force of the actuator can be appropriately controlled without using the vertical G sensor and the stroke sensor and without involving the caster angle set in the suspension.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-47906

However, in the electric suspension device of patent document 1, control target values for a skyhook (bounce) attitude control, a pitch attitude control, and a roll attitude control are calculated in order to suppress changes in the behavior of the vehicle with respect to the bounce (up-down) attitude, the pitch attitude, and the roll attitude. The largest control target value is selected from the respective control target values calculated in this manner. Next, drive control of the actuator is performed using the selected control target value. This suppresses a behavior change of the vehicle.

However, in the case where the maximum control target value is selected from the calculated control target values and the actuator is driven and controlled using the selected control target value as in the electric suspension device of patent document 1, the control target value relating to the posture direction that has not been selected is not reflected in the driving and controlling of the actuator. Therefore, in the electric suspension device of patent document 1, there is room for improvement in appropriately suppressing the behavior change of the vehicle.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electric suspension device capable of appropriately suppressing a change in behavior of a vehicle by performing drive control of an actuator in consideration of all control target values relating to a bounce attitude, a pitch attitude, and a roll attitude.

In order to achieve the above object, an electric suspension device including an actuator that is provided between a vehicle body and a wheel of a vehicle and generates a damping force for damping vibration of the vehicle body, the electric suspension device including: an information acquisition unit that acquires information on the sprung velocity, pitch rate, and roll rate of the vehicle; a bounce target value calculation unit that calculates a bounce target value for controlling a bounce attitude of the vehicle based on the sprung velocity; a pitch target value calculation unit that calculates a pitch target value for controlling the pitch attitude of the vehicle based on the pitch rate; a roll target value calculation unit that calculates a roll target value for roll attitude control of the vehicle based on the roll rate; and a drive control unit that performs drive control of the actuator using a control target load obtained based on a total value of the bounce target value, the pitch target value, and the roll target value.

Effects of the invention

According to the present invention, by performing drive control of the actuator in consideration of all control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, it is possible to appropriately suppress a change in behavior of the vehicle.

Drawings

Fig. 1 is an overall configuration diagram of an electric suspension device of the present invention.

Fig. 2 is a partial sectional view of an electromagnetic actuator provided in the electric suspension device of the present invention.

Fig. 3 is a structural diagram of the inside and the peripheral portion of a load control ECU provided in the electric suspension device of the present invention.

Fig. 4A is a diagram conceptually showing an internal configuration of a 1 st load control ECU provided in a 1 st electric suspension device according to embodiment 1 of the present invention.

Fig. 4B is an explanatory diagram of a bounce target load diagram conceptually showing the relationship of the bounce target load that changes according to the sprung velocity.

Fig. 4C is an explanatory diagram of a pitch target load diagram conceptually showing a relationship of the pitch target load that changes in accordance with the sprung pitch rate.

Fig. 4D is an explanatory diagram of a roll target load diagram conceptually showing the relationship of the roll target load that changes in accordance with the sprung roll rate.

Fig. 4E is an explanatory diagram of a 1 st limit ratio table conceptually showing a relationship of a 1 st limit ratio (limit ratio) that changes in accordance with the sprung velocity.

Fig. 4F is an explanatory diagram of a 2 nd limit ratio table conceptually showing a relationship of the 2 nd limit ratio that changes in accordance with the sprung velocity.

Fig. 5 is a flowchart for explaining the operation of the electric suspension apparatus 1 according to embodiment 1.

Fig. 6A is a diagram conceptually showing an internal configuration of a 2 nd load control ECU provided in a 2 nd electric suspension device according to embodiment 2 of the present invention.

Fig. 6B is an explanatory diagram of a PR integrated target load diagram conceptually showing the relationship between the roll and pitch integrated target loads that change in accordance with the diagonal wheel sprung velocity difference.

Fig. 6C is an explanatory diagram of a 3 rd limit ratio table conceptually showing a relationship of a 3 rd limit ratio that changes in accordance with a difference between the sprung pitch ratio and the sprung roll ratio.

Fig. 6D is an explanatory diagram of a 4 th limit ratio table conceptually showing a relationship of a 4 th limit ratio that changes according to the vehicle speed.

Fig. 7 is a flowchart for explaining the operation of the 2 nd electric suspension device according to embodiment 2.

Description of the reference numerals

10 vehicle

11 electric suspension device

11A 1 st electric suspension device

11B 2 nd electric suspension device

13 electromagnetic actuator (actuator)

41 information acquisition unit

43 target load calculation unit

45 drive control unit

47 bounce target value calculation part

48 pitch target value calculation unit

49 roll target value calculation unit

91 addition unit (drive control unit)

125 addition unit (drive control unit)

Difference in velocity on spring of SD diagonal wheel

SV sprung velocity

PV pitch rate

Roll rate of RV

VS vehicle speed

Detailed Description

Hereinafter, the electric suspension device 11 according to embodiments 1 and 2 of the present invention will be described in detail with reference to the drawings as appropriate.

In the drawings shown below, components having common functions are denoted by the same reference numerals. In this case, duplicate explanation is omitted in principle. In addition, the size and shape of the components may be distorted or exaggerated for convenience of description.

[ common basic configuration of electric suspension 11 according to embodiments 1 and 2 ]

First, a basic configuration common to the electric suspension devices 11 according to embodiments 1 and 2 of the present invention will be described with reference to fig. 1 and 2.

Fig. 1 is a general configuration diagram of an electric suspension system 11 according to embodiments 1 and 2 of the present invention. Fig. 2 is a partial sectional view of the electromagnetic actuator 13 constituting a part of the electric suspension apparatus 11. In the following description, electric suspension devices 11A and 11B according to embodiments 1 and 2 of the present invention will be collectively referred to as an electric suspension device 11 of the present invention.

As shown in fig. 1, an electric suspension device 11 according to the present invention includes a plurality of electromagnetic actuators 13 arranged for respective wheels of a vehicle 10, and a load control ECU 15. The plurality of electromagnetic actuators 13 and the load control ECU15 are connected to each other via an electric power supply line 14 (see the solid line in fig. 1) for supplying drive control electric power from the load control ECU15 to the plurality of electromagnetic actuators 13 and a signal line 16 (see the broken line in fig. 1) for transmitting drive control signals of the electric motor 31 (see fig. 2) from the plurality of electromagnetic actuators 13 to the load control ECU 15.

In the present embodiment, the electromagnetic actuators 13 are disposed for each of the wheels including the front wheel (left and right front wheels) and the rear wheel (left and right rear wheels), and four in total are disposed. The electromagnetic actuators 13 disposed for the respective wheels are driven and controlled independently of each other in accordance with the expansion and contraction operation of the respective wheels.

In the embodiment of the present invention, unless otherwise specified, the plurality of electromagnetic actuators 13 have a common configuration. Therefore, the description of the plurality of electromagnetic actuators 13 is replaced by the description of the configuration of one electromagnetic actuator 13.

As shown in fig. 2, the electromagnetic actuator 13 is configured to include a base housing 17, an outer tube 19, a ball bearing 21, a ball screw shaft 23, a plurality of balls 25, a nut 27, and an inner tube 29.

The base housing 17 supports the base end side of the ball screw shaft 23 via the ball bearing 21 so as to be rotatable around the shaft. The outer tube 19 is provided on the base housing 17 and houses the ball screw mechanism 18 including the ball screw shaft 23, the plurality of balls 25, and the nut 27. The plurality of balls 25 roll along the thread groove of the ball screw shaft 23. The nut 27 is engaged with the ball screw shaft 23 via the plurality of balls 25, and converts the rotational motion of the ball screw shaft 23 into a linear motion. The inner tube 29 connected to the nut 27 is integrated with the nut 27 and displaced in the axial direction of the outer tube 19.

As shown in fig. 2, the electromagnetic actuator 13 includes an electric motor 31, a pair of pulleys 33, and a belt member 35 in order to transmit a rotational driving force to the ball screw shaft 23. The electric motor 31 is provided on the base housing 17 in parallel with the outer tube 19. Pulleys 33 are attached to the motor shaft 31a of the electric motor 31 and the ball screw shaft 23, respectively. A belt member 35 for transmitting the rotational driving force of the electric motor 31 to the ball screw shaft 23 is hung on the pair of pulleys 33.

The electric motor 31 is provided with a resolver (resolver)37 for detecting a rotation angle signal of the electric motor 31. A rotation angle signal of the electric motor 31 detected by the resolver 37 is sent to the load control ECU15 via the signal line 16. The electric motor 31 is controlled to be rotationally driven in accordance with drive control electric power that the load control ECU15 supplies to the plurality of electromagnetic actuators 13 via the electric power supply line 14, respectively.

In the present embodiment, as shown in fig. 2, the axial dimension of the electromagnetic actuator 13 is reduced by adopting a layout in which the motor shaft 31a of the electric motor 31 is disposed substantially parallel to the ball screw shaft 23 and the two are coupled to each other. However, a layout may be adopted in which the motor shaft 31a of the electric motor 31 and the ball screw shaft 23 are arranged coaxially and are connected to each other.

In the electromagnetic actuator 13 of the present embodiment, as shown in fig. 2, a coupling portion 39 is provided at the lower end portion of the base housing 17. The connecting portion 39 is connected and fixed to an unsprung member (a lower arm on the wheel side, a knuckle, and the like) not shown. On the other hand, an upper end portion 29a of the inner tube 29 is coupled and fixed to a sprung member (a shock column (strut tower) portion or the like on the vehicle body side) not shown.

In short, the electromagnetic actuator 13 is provided in parallel with a spring member, not shown, provided between the vehicle body and the wheel of the vehicle 10.

The electromagnetic actuator 13 configured as described above operates as follows. That is, for example, a case where an urging force relating to upward vibration is input to the coupling portion 39 from the wheel side of the vehicle 10 is considered. In this case, the inner tube 29 and the nut 27 are intended to be lowered integrally with respect to the outer tube 19 to which the urging force associated with the upward vibration is applied. Under this influence, the ball screw shaft 23 is intended to rotate in a direction in which the nut 27 descends. At this time, the electric motor 31 is caused to generate a rotational driving force in a direction of inhibiting the nut 27 from descending. The rotational driving force of the electric motor 31 is transmitted to the ball screw shaft 23 via the belt member 35.

In this way, by applying a reaction force (damping force) against the urging force relating to the upward vibration to the ball screw shaft 23, the vibration to be transmitted from the wheel side to the vehicle body side is damped.

[ internal constitution of load control ECU15 ]

Next, the internal and peripheral configurations of the load control ECU15 included in the electric suspension device 11 according to the present invention will be described with reference to fig. 3.

Fig. 3 is a diagram showing the internal and peripheral portions of a load control ECU15 provided in the electric suspension device 11 according to the present invention.

[ electric suspension device of the invention 11 ]

The load control ECU15 included in the electric suspension device 11 according to the present invention is configured to include a microcomputer that performs various arithmetic operations. The load control ECU15 has a drive control function of generating drive forces related to the damping operation and the expansion/contraction operation of the electromagnetic actuators 13 by performing drive control of the plurality of electromagnetic actuators 13 based on the rotation angle signal of the electric motor 31 detected by the resolver 37, the target load TL, and the like.

In order to realize such a drive control function, the load control ECU15 includes an information acquisition unit 41, a target load calculation unit 43, and a drive control unit 45, as shown in fig. 3.

As shown in fig. 3, the information acquisition unit 41 acquires the rotation angle signal of the electric motor 31 detected by the resolver 37 as the time series information on the stroke position, and acquires the information of the sprung mass velocity SV by time differentiating the time series information on the stroke position. The sprung velocity SV is a velocity in the up-down direction of the sprung (vehicle body).

As shown in fig. 3, the information acquiring unit 41 acquires the sequence information of the sprung pitch rate (hereinafter, sometimes simply referred to as "pitch rate") PV, the sprung roll rate (hereinafter, sometimes simply referred to as "roll rate") RV, and the angular wheel sprung velocity difference SD. The information on the pitch rate PV and the roll rate RV may be acquired by, for example, a gyro sensor (not shown) provided in the vehicle 10.

The information on the diagonal wheel sprung velocity difference SD may be obtained by obtaining information on the sprung velocity SV of the diagonal wheel and calculating the difference between the two.

Further, as shown in fig. 3, the information acquisition unit 41 acquires the timing information of each of the vehicle speed VS, the stroke position of the electromagnetic actuator 13, and the motor current of the electric motor 31.

The information on the sprung velocity SV, the pitch rate PV, the roll rate RV, the diagonal wheel sprung velocity difference SD, the vehicle speed VS, the stroke position of the electromagnetic actuator 13, and the motor current related to the electric motor 31 acquired by the information acquisition unit 41 are sent to the target load calculation unit 43, respectively.

As shown in fig. 3, the target load calculation unit 43 has a function of calculating a target load TL, which is a target value of the damping operation and the expansion/contraction operation of the electromagnetic actuator 13.

In particular, in the present invention, for the purpose of performing drive control of the electromagnetic actuator 13 while taking into account all the control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, the target load calculation unit 43 includes a bounce target value calculation unit 47, a pitch target value calculation unit 48, and a roll target value calculation unit 49, as shown in fig. 3.

The bounce target value calculation unit 47 calculates a bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV.

The pitch target value calculation unit 48 calculates a pitch target value for pitch attitude control of the vehicle 10 based on the sprung pitch rate PV.

The roll target value calculation unit 49 calculates a roll target value for roll attitude control of the vehicle 10 based on the sprung roll rate RV.

The internal configurations of the bounce target value calculation unit 47, the pitch target value calculation unit 48, and the roll target value calculation unit 49 provided in the target load calculation unit 43 will be described in detail later.

The drive control unit 45 calculates a target current value that can achieve the target load TL determined by the target load calculation unit 43. Next, the drive control unit 45 performs drive control of the electric motors 31 provided in the respective electromagnetic actuators 13 so that the motor currents related to the electric motors 31 follow the calculated target current values. In each of the plurality of electromagnetic actuators 13, the drive control of the electric motor 31 is performed independently.

In addition, the drive control unit 45 can preferably use, for example, an inverter control circuit when generating the drive control electric power to be supplied to the electric motor 31.

[ constitution of main part of 1 st load control ECU15A provided in 1 st electric suspension device 11A ]

Next, the configuration of the main part of the 1 st load control ECU15A included in the 1 st electric suspension system 11A according to embodiment 1 of the present invention will be described with reference to fig. 4A to 4F as appropriate.

Fig. 4A is a diagram conceptually showing a configuration of a main part of a 1 st load control ECU15A provided in a 1 st electric suspension device 11A according to embodiment 1 of the present invention. Fig. 4B is an explanatory diagram conceptually showing a bounce target load map of the relationship of the bounce target load BTL that changes in accordance with the sprung velocity SV. Fig. 4C is an explanatory diagram of a pitch target load diagram conceptually showing the relationship of the pitch target load TL that varies according to the pitch rate PV. Fig. 4D is an explanatory diagram of a roll target load diagram conceptually showing the relationship of the roll target load TL that changes in accordance with the roll rate RV. Fig. 4E is an explanatory diagram of a 1 st limit ratio table conceptually showing a relationship of the limit ratio LR value that changes in accordance with the sprung velocity SV. Fig. 4F is an explanatory diagram of a 2 nd limit ratio table conceptually showing a relationship of the limit ratio LR value that changes in accordance with the sprung velocity SV.

The 1 st load control ECU15A included in the 1 st electric suspension device 11A includes a bounce target value calculation unit 47, a pitch target value calculation unit 48, a roll target value calculation unit 49, and an addition unit 91.

[ internal constitution of the pop-up target value calculation section 47 ]

The bounce target value calculation unit 47 is configured to include a bounce gain (B gain) setting unit 51, a bounce target load calculation unit 53, a first multiplication unit 55, an extension-side gain (Ten gain) setting unit 61, a shortening-side gain (Comp gain) setting unit 63, a selection unit 65, and a second multiplication unit 70, in order to obtain a bounce target value that can appropriately maintain the bounce attitude.

The B gain setting unit 51 sets a predetermined pop-up gain (B gain). The B gain set by the B gain setting unit 51 is sent to the primary multiplying unit 55.

The bounce target load calculation unit 53 calculates a value of the bounce target load BTL corresponding to the sprung velocity SV. When calculating the bounce target load BTL, the bounce target load calculation unit 53 refers to the information of the sprung velocity SV acquired by the information acquisition unit 41 and the bounce target load map (see fig. 4A and 4B) 52. The bounce target load map 52 is a graph conceptually showing the relationship (bounce target load characteristic) of the bounce target load BTL that changes in accordance with the sprung velocity SV.

The value of the pop-up target load BTL calculated by the pop-up target load calculation unit 53 is sent to the primary multiplication unit 55. 0

Note that, as for the storage content of the bounce target load map 52, the target value of the damping force control current may be used instead of the value of the bounce target load BTL.

Here, the pop-up target load characteristics of the pop-up target load map 52 will be described with reference to fig. 4B.

As shown by dividing the abscissa of fig. 4B, the change region of the sprung velocity SV in the bounce target load map 52 is constituted by the 1 st velocity region SV1 and the 2 nd velocity region SV 2. In the sprung velocity SV shown on the horizontal axis in fig. 4B, a region exceeding 0 indicates the velocity on the extension side, and a region below 0 indicates the velocity on the contraction side.

The 1 st velocity region SV1 is a velocity region in which the sprung velocity SV falls below the 1 st velocity threshold SVth1(| SV-SVth 1| ≦ 0). The 1 st speed threshold SVth1 is a threshold for dividing a common speed region among all speed regions of the sprung speed SV. Therefore, the sprung velocity SV generated in the scene of traveling along the general paved road converges mostly to the 1 st velocity region SV 1.

The 2 nd velocity region SV2 is a velocity region in which the sprung velocity SV exceeds the 1 st velocity threshold SVth1(| SV-SVth 1| > 0). Therefore, the sprung velocity SV, which is generated in a severe traveling scene such as when the wheels of the vehicle 10 climb over the hill, reaches the 2 nd velocity region SV 2.

Further, as the 1 st speed threshold SVth1, a probability density function of the sprung speed SV may be evaluated through experiments, simulations, and the like, and an appropriate value may be set in consideration of a case where the distribution ratio of the sprung speed SV appearing in the 1 st speed region SV1 and the 2 nd speed region SV2, respectively, satisfies a predetermined distribution ratio with reference to the evaluation result.

As shown in fig. 4B, the bounce target load characteristic of the bounce target load map 52 in the 1 st speed region SV1 has a characteristic in which the bounce target load BTL takes a fixed value (zero) regardless of a change in the sprung speed SV. That is, when the sprung velocity SV is in the range of the 1 st velocity region SV1 (-SVth 1 < SV < SVth1), the bounce target load BTL corresponding thereto also becomes zero.

In contrast, as shown in fig. 4B, the bounce target load characteristic of the bounce target load map 52 in the 2 nd speed region SV2 has the following characteristics: as the sprung velocity SV is directed to the extension side and becomes larger, the bounce target load BTL directed to the shortening side becomes larger in infinite order of magnitude; on the other hand, as the sprung speed SV is directed to the shortened side and becomes larger, the bounce target load BTL directed to the extended side becomes larger in infinite order of scale.

The primary multiplying unit 55 multiplies the B gain set by the B gain setting unit 51 by the value of the pop-up target load BTL calculated by the pop-up target load calculating unit 53. The multiplication result of the primary multiplication unit 55 is sent to the secondary multiplication unit 70.

A predetermined extension-side gain (Ten gain) related to the sprung velocity SV is set in the Ten gain setting unit 61. The Ten gain set by the Ten gain setting unit 61 is sent to the selection unit 65.

The Comp gain setting unit 63 sets a predetermined shortening-side gain (Comp gain) related to the sprung velocity SV. The Comp gain set by the Comp gain setting unit 63 is sent to the selection unit 65.

The selection unit 65 selects one of the Ten gain set by the Ten gain setting unit 61, the Comp gain set by the Comp gain setting unit 63, and the sprung velocity SV according to a predetermined flow. The information selected by the selection unit 65 is sent to the quadratic multiplication unit 70.

The second multiplier 70 multiplies the multiplication result of the first multiplier 55 by the information selected by the selector 65. The multiplication result of the second multiplication unit 70 is sent to the addition unit 91 (described later in detail).

[ internal constitution of the pitch target value calculation section 48 ]

The pitch target value calculation unit 48 is configured to include a pitch gain (P gain) setting unit 71, a pitch target load calculation unit 73, a first multiplication unit 75, an ABS conversion unit 77, a 1 st limit ratio calculation unit 79, and a second multiplication unit 80, for the purpose of obtaining a pitch target value that can appropriately maintain the pitch attitude.

The P gain setting unit 71 sets a predetermined pitch gain (P gain). The P gain set by the P gain setting unit 71 is sent to the first multiplier 75.

The pitch target load calculation section 73 calculates a value of the pitch target load PTL according to the pitch rate PV. When performing this calculation, the pitch target load calculation unit 73 refers to the information of the pitch rate PV acquired by the information acquisition unit 41 and a pitch target load map (see fig. 4A and 4C)72 conceptually showing the relationship (pitch target load characteristic) of the pitch target load PTL that changes according to the pitch rate PV. The value of the pitch target load PTL calculated by the pitch target load calculation unit 73 is sent to the first multiplication unit 75.

Further, as for the stored contents of the pitch target load map 72, the target value of the damping force control current may also be used instead of the value of the pitch target load PTL.

Here, the pitch target load characteristics of the pitch target load map 72 will be described with reference to fig. 4C.

As shown by dividing the abscissa of fig. 4C, the change region of the pitch rate PV in the pitch target load map 72 is composed of the 1 st velocity region PV1 and the 2 nd velocity region PV 2. In the pitch rate PV shown on the abscissa of fig. 4C, a region exceeding 0 indicates a ratio (rate) on the extension side, and a region below 0 indicates a ratio on the shortening side. As the pitch rate PV shown on the horizontal axis in fig. 4C, a value obtained by converting the change speed in the pitch direction of the vehicle 10 into the expansion/contraction speed (stroke speed) of the electromagnetic actuator 13 may be used. Similarly, as the pitch target load PTL shown on the vertical axis in fig. 4C, a value obtained by converting the target load in the pitch direction of the vehicle 10 into the target load in the expansion/contraction (stroke) direction of the electromagnetic actuator 13 may be used.

The 1 st velocity region PV1 is a velocity region in which the pitch rate PV falls below a velocity threshold PVth (| PV-PVth | ≦ 0). The velocity threshold value PVth is a threshold value for dividing a common velocity region among all velocity regions of the pitch rate PV. Therefore, the pitch rate PV generated in the scene traveling along the general paved road mostly converges to the 1 st speed region PV 1.

The 2 nd velocity region PV2 is a velocity region in which the pitch rate PV exceeds a velocity threshold PVth (| PV — velocity threshold PVth | > 0). Therefore, the pitch rate PV, which is generated in a severe traveling scene such as when the vehicle 10 travels along a corrugated road, reaches the 2 nd speed region PV 2.

Further, as the speed threshold value PVth, a probability density function of the pitch rate PV may be evaluated through experiments, simulations, and the like, and an appropriate value may be set in consideration of a case where the distribution ratio of the pitch rate PV appearing in each of the 1 st speed region PV1 and the 2 nd speed region PV2 satisfies a predetermined distribution ratio with reference to the evaluation result.

As shown in fig. 4C, the pitch target load characteristic of the pitch target load map 72 in the 1 st velocity region PV1 has a characteristic that the pitch target load PTL takes a fixed value (zero) regardless of a change in the pitch rate PV. That is, when the pitch rate PV is within the range of the 1 st velocity region PV1 (-PVth < PV < PVth), the pitch target load PTL corresponding thereto also becomes zero.

In contrast, as shown in fig. 4C, the pitch target load characteristic of the pitch target load map 72 in the 2 nd velocity region PV2 has the following characteristics: as the pitch rate PV is directed to the extension side and becomes larger, the pitch target load PTL directed to the shortening side becomes larger in an infinite order of magnitude; on the other hand, as the pitch rate PV is directed to the shortening side and becomes larger, the pitch target load PTL directed to the extension side becomes larger in an infinite order of magnitude.

The primary multiplying unit 75 multiplies the P gain set by the P gain setting unit 71 by the value of the pitch target load PTL calculated by the pitch target load calculating unit 73. The multiplication result of the primary multiplication unit 75 is sent to the secondary multiplication unit 80.

The ABS conversion unit 77 converts the absolute value of the information of the sprung velocity SV acquired by the information acquisition unit 41. The information on the sprung velocity SV after the absolute value conversion by the ABS conversion unit 77 is sent to the 1 st limit ratio calculation unit 79.

The 1 st limit ratio calculator 79 calculates a value of the 1 st limit ratio LR1 corresponding to the sprung velocity SV. When calculating the 1 st limit ratio LR1, the 1 st limit ratio calculator 79 refers to the information on the sprung mass velocity SV acquired by the information acquirer 41 and the 1 st limit ratio table (see fig. 4A and 4E) 78. The 1 st limit ratio table 78 is a table conceptually showing a relationship of a limit ratio of the electromagnetic actuator 13 with respect to the expansion/contraction control amount (hereinafter, the "limit ratio with respect to the expansion/contraction control amount" may be simply referred to as "limit ratio") that changes in accordance with the sprung mass velocity SV.

The value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculation unit 79 is sent to the quadratic multiplication unit 80.

Here, the 1 st limit ratio table 78 will be described with reference to fig. 4E.

As shown in fig. 4E, the change region of the sprung velocity SV in the 1 st limit ratio map 78 is formed of a total of three velocity regions, i.e., the 11 th velocity region SV11, the 12 th velocity region SV12, and the 13 th velocity region SV13, in ascending order of the sprung velocity SV.

The 11 th velocity region SV11 is a velocity region when the sprung velocity SV falls below the 11 th velocity threshold SVth11(| SV-SVth 11| ≦ 0). The 11 th speed threshold SVth11 is an upper limit threshold for dividing a normal speed region among all speed regions of the sprung mass speed SV, similarly to the 1 st speed threshold SVth1 described above. Therefore, the sprung velocity SV generated in the scene of traveling along the general paved road converges mostly to the 11 th velocity region SV 11.

In the present embodiment, the 11 th speed threshold SVth11 is set to a value different from the 1 st speed threshold SVth1 of the pop-up target load map 52 (for example, the 1 st speed threshold SVth1 < the 11 th speed threshold SVth 11). However, the 1 st speed threshold SVth1 and the 11 th speed threshold SVth11 may be the same value. Further, the relationship of the magnitude of (1 st speed threshold SVth1 > 11 th speed threshold SVth11) may be used.

Both the 12 th velocity region SV12 and the 13 th velocity region SV13 are velocity regions when the sprung velocity SV exceeds the 11 th velocity threshold SVth11(| SV-SVth 11| > 0). Therefore, the sprung speed SV, which is generated in a severe traveling scene such as when the wheels of the vehicle 10 climb over a stepped hill, reaches the 12 th speed region SV12 and the 13 th speed region SV 13.

In embodiment 1, the 12 th speed range SV12 and the 13 th speed range SV13 are divided so as to sandwich the 12 th speed threshold SVth 12. The 12 th speed threshold SVth12 is a threshold for dividing a high speed region where the sprung mass speed SV generated in a severe traveling scene reaches into two more regions. The sprung speed SV belonging to the 13 th speed region SV13 is set higher than the sprung speed SV belonging to the 12 th speed region SV 12.

In the present embodiment, the 12 th speed region SV12 and the 13 th speed region SV13 correspond to the 2 nd speed region SV2 of the pop-up target load map 52.

On the other hand, as shown in the vertical axis of fig. 4E, a fixed value (1), a variable value (1 > LR1 > 0.8), and a fixed value (0.8) are set as the values of the 1 st limit ratio LR1 corresponding to the velocity region of the sprung velocity SV.

In the example of fig. 4E, each value of the sprung velocity SV belonging to the 11 th velocity range SV11 can be replaced with a fixed value (1) of the 1 st limit ratio LR 1.

The gist of the configuration is to use the characteristic value of the pitch target load PTL calculated by the pitch target load calculation unit 73 in a region where the sprung mass velocity SV is relatively low, that is, in the 11 th velocity region SV11, without performing the limitation by the 1 st limitation ratio LR 1.

For example, each value of the sprung velocity SV belonging to the 12 th velocity range SV12 is replaced in a one-to-one manner by a value belonging to the range (1 to 0.8) corresponding to the value of the sprung velocity SV via a predetermined linear function connecting the fixed values (1) to (0.8) of the 1 st limit ratio LR 1. For example, the 11 th speed threshold SVth11 can be replaced with a fixed value (1) of the 1 st limit ratio LR 1. The 12 th speed threshold SVth12 can be replaced with a fixed value (0.8) of the 1 st limit ratio LR 1.

The gist of the configuration is that, in the 12 th velocity range SV12, which is a range where the sprung velocity SV is relatively medium, a variable value having a linear characteristic in which the value of the 1 st limit ratio LR1 decreases as the sprung velocity SV increases is assigned, and the characteristic value of the pitch target load PTL is used so as to decrease as the sprung velocity SV increases.

Further, for example, each value of sprung velocity SV belonging to 13 th velocity range SV13 can be replaced with a fixed value (0.8) of 1 st limit ratio LR 1.

The gist of the configuration is that the characteristic value of the pitch target load PTL calculated by the pitch target load calculation unit 73 is reduced and used by performing predetermined limitation based on the 1 st limitation ratio LR1 in the 13 th speed range SV13, which is a range where the sprung mass velocity SV is relatively high.

Note that, instead of the form shown in fig. 4E in which the fixed value (1), the variable value (1 > LR1 > 0.8), and the fixed value (0.8) are set, respectively, the form shown in fig. 4F may be adopted as the value of the 1 st limit ratio LR1 corresponding to the velocity region of the sprung velocity SV.

That is, in the example of fig. 4F, the 2 nd limit ratio calculation unit 89 calculates the value of the 2 nd limit ratio LR2 corresponding to the sprung mass velocity SV. When calculating the 2 nd limit ratio LR2, the 2 nd limit ratio calculation unit 89 refers to the information on the sprung mass velocity SV acquired by the information acquisition unit 41 and the 2 nd limit ratio map (see fig. 4F) 88. A fixed value (0.8), a variable value (0.8 < LR2 < 1), and a fixed value (1) are set as values of the 2 nd limit ratio LR2 corresponding to the speed region of the sprung mass speed SV in the 2 nd limit ratio table 88.

In the example of fig. 4F, each value of the sprung velocity SV belonging to the 11 th velocity range SV11 can be replaced with a fixed value (0.8) of the 2 nd limit ratio LR 2.

For example, each value of the sprung velocity SV belonging to the 12 th velocity range SV12 is replaced in a one-to-one manner by a value belonging to the range of (0.8 to 1) corresponding to the value of the sprung velocity SV via a predetermined linear function connecting the fixed values (0.8) to (1) of the 2 nd limit ratio LR 2. For example, the 11 th speed threshold SVth11 can be replaced with a fixed value (0.8) of the 2 nd limit ratio LR 2. The 12 th speed threshold SVth12 can be replaced with a fixed value (1) of the 2 nd limiting ratio LR 2.

Further, for example, each value of the sprung velocity SV belonging to the 13 th velocity range SV13 can be replaced with the fixed value (1) of the 2 nd limit ratio LR 2.

In this case, the value of the 2 nd limit ratio LR2 calculated by the 2 nd limit ratio calculation unit 88 is sent to the quadratic multiplication unit 80.

The secondary multiplier 80 multiplies the multiplication result of the primary multiplier 75 by the value of the 1 st limiting ratio LR1 obtained by the 1 st limiting ratio calculator 79 (or the value of the 2 nd limiting ratio LR2 obtained by the 2 nd limiting ratio calculator 89). The multiplication result of the second multiplication unit 80 is sent to an addition unit 91 (described later in detail).

[ internal constitution of the roll target value calculation unit 49 ]

The roll target value calculation unit 49 is configured to include a roll gain (R gain) setting unit 81, a roll target load calculation unit 83, a first multiplier 85, an ABS conversion unit 77, a 1 st limit ratio calculation unit 79, and a second multiplier 90, in order to obtain a roll target value that can properly maintain the roll posture.

The R gain setting unit 81 sets a predetermined roll gain (R gain). The R gain set by the R gain setting unit 81 is sent to the first multiplier 85.

The roll target load calculation unit 83 calculates a value of the roll target load RTL according to the roll rate RV. When performing this calculation, the roll target load calculation unit 83 refers to the information of the roll rate RV acquired by the information acquisition unit 41 and a roll target load map (see fig. 4A and 4D)82 conceptually showing the relationship (roll target load characteristic) of the roll target load RTL that changes according to the roll rate RV. The value of the roll target load RTL calculated by the roll target load calculation unit 83 is sent to the primary multiplication unit 85.

Further, as for the storage content of the roll target load map 82, the target value of the damping force control current may be used instead of the value of the roll target load RTL.

Here, the roll target load characteristics of the roll target load map 82 will be described with reference to fig. 4D.

As shown by dividing the abscissa of fig. 4D, the change region of the roll rate RV in the roll target load map 82 is composed of the 1 st velocity region RV1 and the 2 nd velocity region RV 2. In the roll rate RV shown on the horizontal axis of fig. 4D, a region exceeding 0 indicates the ratio of the extension side, and a region below 0 indicates the ratio of the shortening side. As the roll rate RV shown on the horizontal axis in fig. 4D, a value obtained by converting the change speed in the roll direction of the vehicle 10 into the expansion/contraction speed (stroke speed) of the electromagnetic actuator 13 may be used. Similarly, as the roll target load RTL shown on the vertical axis in fig. 4D, a value obtained by converting the target load in the roll direction of the vehicle 10 into the target load in the expansion/contraction (stroke) direction of the electromagnetic actuator 13 may be used.

The 1 st velocity region RV1 is a velocity region in which the roll rate RV falls below the velocity threshold RVth (| RV-RVth | ≦ 0). The velocity threshold RVth is a threshold for dividing a common velocity region among all velocity regions of the roll rate RV. Therefore, the roll rate RV generated in a scene traveling straight along a general paved road mostly converges on the 1 st speed region RV 1.

The 2 nd velocity region RV2 is a velocity region in which the roll rate RV exceeds the velocity threshold RVth (| RV — velocity threshold RVth | > 0). Therefore, the roll rate RV generated in a driving scene such as the vehicle 10 traveling along a curved road reaches the 2 nd speed region RV 2.

Further, as the velocity threshold value RVth, a probability density function of the roll rate RV may be evaluated through experiments, simulations, and the like, and an appropriate value may be set in consideration of a case where the distribution ratio of the roll rate RV appearing in each of the 1 st velocity region RV1 and the 2 nd velocity region RV2 satisfies a predetermined distribution ratio with reference to the evaluation result.

As shown in fig. 4D, the roll target load characteristic of the roll target load map 82 in the 1 st velocity region RV1 has a characteristic in which the roll target load RTL takes a fixed value (zero) regardless of the change in the roll rate RV. That is, when the roll rate RV is within the range of the 1 st velocity region RV1 (-RVth < RV < RVth), the roll target load RTL corresponding thereto also becomes zero.

In contrast, as shown in fig. 4D, the roll target load characteristic of the roll target load map 82 in the 2 nd velocity region RV2 has the following characteristics: as the roll rate RV is directed to the extension side and becomes larger, the roll target load RTL directed to the shortening side becomes larger in an infinite order of magnitude; on the other hand, as the roll rate RV is directed to the shortening side and becomes larger, the roll target load RTL directed to the extension side becomes larger in an infinite order of magnitude.

The primary multiplying unit 85 multiplies the R gain set by the R gain setting unit 81 by the value of the roll target load RTL calculated by the roll target load calculating unit 83. The multiplication result of the primary multiplication unit 85 is sent to the secondary multiplication unit 90.

The ABS conversion unit 77 converts the absolute value of the information of the sprung velocity SV acquired by the information acquisition unit 41. The information on the sprung velocity SV after the absolute value conversion by the ABS conversion unit 77 is sent to the 1 st limit ratio calculation unit 79.

As described above, the 1 st limit ratio calculator 79 calculates the value of the 1 st limit ratio LR1 corresponding to the sprung velocity SV.

The value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculation unit 79 is sent to the quadratic multiplication unit 90.

The second multiplier 90 multiplies the multiplication result of the first multiplier 85 by the value of the 1 st limiting ratio LR1 obtained by the 1 st limiting ratio calculator 79 (or the value of the 2 nd limiting ratio LR2 obtained by the 2 nd limiting ratio calculator 89). The multiplication result of the second multiplication unit 90 is sent to an addition unit 91 (described later in detail).

The adder 91 adds the multiplication result (bounce target value) by the secondary multiplier 70 belonging to the bounce target value calculator 47, the multiplication result (pitch target value) by the secondary multiplier 80 belonging to the pitch target value calculator 48, and the multiplication result (roll target value) by the secondary multiplier 90 belonging to the roll target value calculator 49.

The adder 91 constitutes a part of the "drive control unit 45" of the present invention.

The addition result of the addition unit 91, that is, the integrated target load obtained by integrating all the control target values regarding the bounce attitude, the pitch attitude, and the roll attitude is transmitted to the electromagnetic actuators 13 provided on the wheels FL (front left), FR (front right), RL (rear left), and RR (rear right).

[ action of 1 st electric suspension device 11A ]

Next, the operation of the 1 st electric suspension device 11A according to embodiment 1 of the present invention will be described with reference to fig. 5. Fig. 5 is a flowchart for explaining the operation of the 1 st electric suspension device 11A according to embodiment 1 of the present invention.

In step S11 shown in fig. 5, the information acquisition unit 41 of the 1 st load control ECU15A acquires the rotation angle signal of the electric motor 31 detected by the resolver 37 as the time series information on the stroke position, and acquires the information of the sprung velocity SV by time differentiating the time series information on the stroke position.

The information acquisition unit 41 acquires information on the pitch rate PV, roll rate RV, and diagonal wheel spring velocity difference SD.

Further, the information acquisition unit 41 acquires information on the vehicle speed VS, the stroke position of the electromagnetic actuator 13, and the motor current related to the electric motor 31.

The information on the sprung velocity SV, the pitch rate PV, the roll rate RV, the diagonal wheel sprung velocity difference SD, the vehicle speed VS, the stroke position of the electromagnetic actuator 13, and the motor current related to the electric motor 31 acquired by the information acquisition unit 41 are sent to the target load calculation unit 43, respectively.

In step S12, the bounce target value calculation unit 47 of the target load calculation unit 43 belonging to the 1 st load control ECU15A calculates a bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV.

Specifically, in the bounce target value calculation unit 47, the primary multiplication unit 55 multiplies the B gain set by the B gain setting unit 51 by the value of the bounce target load BTL calculated by the bounce target load calculation unit 53. The multiplication result of the primary multiplication unit 55 is sent to the secondary multiplication unit 70.

The selection unit 65 selects one of the Ten gain set by the Ten gain setting unit 61, the Comp gain set by the Comp gain setting unit 63, and the sprung velocity SV according to a predetermined flow. The information selected by the selection unit 65 is sent to the quadratic multiplication unit 70.

The second multiplier 70 multiplies the multiplication result of the first multiplier 55 by the information selected by the selector 65. Thus, the pop-up target value can be obtained by the calculation of the pop-up target value calculation unit 47. The multiplication result (pop-up target value) by the secondary multiplying unit 70 is sent to the adding unit 91.

In step S13, the pitch target value calculation unit 48 of the target load calculation unit 43 belonging to the 1 st load control ECU15A calculates a pitch target value for pitch attitude control of the vehicle 10 based on the pitch rate PV.

Specifically, in the pitch target value calculation unit 48, the primary multiplication unit 75 multiplies the P gain set by the P gain setting unit 71 by the value of the pitch target load PTL calculated by the pitch target load calculation unit 73. The multiplication result of the primary multiplication unit 75 is sent to the secondary multiplication unit 80.

The 1 st limit ratio calculator 79 calculates a value of the 1 st limit ratio LR1 corresponding to the sprung velocity SV. The value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculation unit 79 is sent to the quadratic multiplication unit 80.

The secondary multiplier 80 multiplies the multiplication result of the primary multiplier 75 by the value of the 1 st limiting ratio LR1 obtained by the 1 st limiting ratio calculator 79 (or the value of the 2 nd limiting ratio LR2 obtained by the 2 nd limiting ratio calculator 89). Thus, the pitch target value can be obtained by the calculation of the pitch target value calculation unit 48. The multiplication result (pitch target value) by the quadratic multiplication unit 80 is sent to the addition unit 91.

In step S14, the roll target value calculation unit 49 belonging to the target load calculation unit 43 of the 1 st load control ECU15A calculates a roll target value for roll attitude control of the vehicle 10 based on the roll rate RV.

Specifically, in the roll target value calculation unit 49, the primary multiplier 85 multiplies the R gain set by the R gain setting unit 81 by the value of the roll target load RTL calculated by the roll target load calculation unit 83. The multiplication result of the primary multiplication unit 85 is sent to the secondary multiplication unit 90.

As described above, the 1 st limit ratio calculator 79 calculates the value of the 1 st limit ratio LR1 corresponding to the sprung velocity SV. The value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculation unit 79 is sent to the quadratic multiplication unit 90.

The second multiplier 90 multiplies the multiplication result of the first multiplier 85 by the value of the 1 st limiting ratio LR1 obtained by the 1 st limiting ratio calculator 79 (or the value of the 2 nd limiting ratio LR2 obtained by the 2 nd limiting ratio calculator 89). Thus, the roll target value can be obtained by the calculation of the roll target value calculation unit 49. The multiplication result (roll target value) by the secondary multiplying unit 90 is sent to the adding unit 91.

In step S15, the adder 91 of the drive control unit 45 belonging to the 1 st load control ECU15A adds the multiplication result (bounce target value) by the secondary multiplier 70 belonging to the bounce target value calculator 47, the multiplication result (pitch target value) by the secondary multiplier 80 belonging to the pitch target value calculator 48, and the multiplication result (roll target value) by the secondary multiplier 90 belonging to the roll target value calculator 49. Thereby, an integrated target load obtained by integrating all the control target values regarding the bounce attitude, the pitch attitude, and the roll attitude is calculated.

In step S16, the drive control unit 45 of the 1 st load control ECU15A executes drive control of the electromagnetic actuator 13 based on the integrated target load calculated in step S15.

According to the electric suspension device 11A of the first aspect, the drive control of the electromagnetic actuator 13 is performed in consideration of all the control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, thereby appropriately suppressing the behavior change of the vehicle 10.

[ constitution of main part of the 2 nd load control ECU15B provided in the 2 nd electric suspension device 11B ]

Next, the configuration of the main part of the 2 nd load control ECU15B included in the 2 nd electric suspension system 11B according to embodiment 2 of the present invention will be described with reference to fig. 6A to 6C as appropriate.

Fig. 6A is a diagram conceptually showing a configuration of a main part of the 2 nd load control ECU15B provided in the 2 nd electric suspension device 11B. Fig. 6B is an explanatory diagram of the PR integrated target load map 104 conceptually showing the relationship between the roll and pitch integrated target loads PRTL that change in accordance with the diagonal wheel sprung velocity difference SD. Fig. 6C is an explanatory diagram of the 3 rd limit ratio table 116 conceptually showing the relationship of the 3 rd limit ratio LR3 that changes in accordance with the difference between the roll rate RV and the pitch rate PV. Fig. 6D is an explanatory diagram of the 4 th limit ratio table 120 conceptually showing the relationship of the 4 th limit ratio LR4 that changes in accordance with the vehicle speed VS.

The 2 nd load control ECU15B included in the 2 nd electric suspension device 11B includes a bounce target value calculation unit 47, a PR integrated target value calculation unit 101, and an addition unit 125.

The pop-up target value calculation unit 47 belonging to the 2 nd load control ECU15B has the same internal configuration as the pop-up target value calculation unit 47 belonging to the 1 st load control ECU 15A. Therefore, the internal configuration of the bounce target value calculation unit 47 belonging to the 2 nd load control ECU15B will not be described.

[ PR integration target value calculation section 101 internal configuration ]

The PR integrated target value calculation unit 101 aims to obtain a PR integrated target value that can appropriately hold both the pitch posture and the roll posture.

In the process of research and development of the electric suspension device 11A of the first embodiment 1, the present inventors have made extensive studies on how to adopt a technical means for performing suppression control with respect to the pitch attitude and the roll attitude with high balance.

Therefore, it is conceivable to adopt the diagonal wheel sprung velocity difference SD as a parameter that can collectively execute the suppression control relating to the pitch attitude and the roll attitude.

Further, it has been found that the information on the pitch rate PV and the roll rate RV enables appropriate balance adjustment for the pitch posture and the roll posture.

The invention of embodiment 2 has been completed in which the suppression control of the pitch attitude and the roll attitude is performed using the diagonal wheel sprung velocity difference SD as a parameter, and the balance adjustment of the pitch attitude and the roll attitude is performed using the information of the pitch rate PV and the roll rate RV, thereby achieving the object of performing the suppression control of the pitch attitude and the roll attitude with high balance.

To achieve the above object, the PR integrated target value calculation unit 101 includes an ABS conversion unit 77, a 1 st limit ratio calculation unit 79, a pitch and roll gain (PR gain) setting unit 103, a PR integrated target load calculation unit 105, an extension-side gain (Ten gain) setting unit 107, a shortening-side gain (Comp gain) setting unit 109, a selection unit 111, a first multiplication unit 113, a subtraction unit 115, a 3 rd limit ratio calculation unit 117, a second multiplication unit 119, a 4 th limit ratio calculation unit 121, and a third multiplication unit 123.

The ABS conversion unit 77 converts the absolute value of the information of the sprung velocity SV acquired by the information acquisition unit 41. The information on the sprung velocity SV after the absolute value conversion by the ABS conversion unit 77 is sent to the 1 st limit ratio calculation unit 79.

The 1 st limit ratio calculator 79 calculates a value of the 1 st limit ratio LR1 corresponding to the sprung velocity SV. The value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculation unit 79 is sent to the quadratic multiplication unit 119.

A PR gain setting unit 103 sets predetermined pitch and roll gains (PR gains). The PR gain set by the PR gain setting unit 103 is sent to the first multiplication unit 113.

The PR integrated target load calculation unit 105 calculates a value of the PR integrated target load PRTL corresponding to the diagonal wheel sprung speed difference SD. When this calculation is performed, the PR integration target load calculation unit 105 refers to the information of the diagonal wheel sprung speed difference SD acquired by the information acquisition unit 41 and a PR integration target load map (see fig. 6A and 6B)104 conceptually showing the relationship (PR integration target load characteristics) of the PR integration target load PRTL that changes according to the diagonal wheel sprung speed difference SD. The value of the PR integration target load PRTL calculated by the PR integration target load calculation unit 105 is sent to the primary multiplication unit 113.

In addition, as for the stored content of the PR integration target load map 104, a target value of the damping force control current may be used instead of the value of the PR integration target load PRTL.

Here, the PR integrated target load characteristics of the PR integrated target load map 104 will be described with reference to fig. 6B.

As shown by dividing the horizontal axis of fig. 6B, the change region of the diagonal wheel sprung velocity difference SD in the PR integration target load map 104 is constituted by the 1 st velocity region SD1 and the 2 nd velocity region SD 2. In the diagonal wheel sprung speed difference SD shown on the horizontal axis of fig. 6B, the region exceeding 0 indicates the speed difference on the extension side, and the region below 0 indicates the speed difference on the contraction side.

The extension-side speed difference means that the direction of differential speed relating to the diagonal wheel spring speed difference SD points to the extension side. In addition, the speed difference at the shortened side means that the direction of the differential speed related to the speed difference SD on the diagonal wheel spring is directed to the shortened side.

The 1 st speed region SD1 is a speed region in which the diagonal wheel sprung speed difference SD falls below the speed difference threshold SDth (| SD-SDth | ≦ 0). The speed difference threshold value SDth is a threshold value for dividing a common speed region among all the speed regions of the diagonal wheel sprung speed difference SD. Therefore, the diagonal wheel sprung speed difference SD generated in a scene of traveling along a general paved road mostly converges on the 1 st speed region SD 1.

The 2 nd speed region SD2 is a speed region where the diagonal wheel sprung speed difference SD exceeds the speed difference threshold SDth (| SD-SDth | > 0). Therefore, diagonal wheel-sprung speed difference SD, which occurs in a severe driving scene such as when vehicle 10 is traveling over rough terrain, reaches second speed region SD 2.

Further, as the speed difference threshold value SDth, a probability density function of the diagonal wheel sprung speed difference SD may be evaluated through experiments, simulations, and the like, and an appropriate value may be set by considering a case where the distribution ratio of the diagonal wheel sprung speed difference SD appearing in each of the 1 st speed region SD1 and the 2 nd speed region SD2 satisfies a predetermined distribution ratio with reference to the evaluation result.

As shown in fig. 6B, the PR integrated target load characteristic of the PR integrated target load map 104 in the 1 st speed region SD1 has a characteristic in which the PR integrated target load PRTL takes a fixed value (zero) regardless of the change in the diagonal wheel sprung speed difference SD. That is, when the diagonal wheel sprung speed difference SD is within the range of the 1 st speed region SD1 (-SDth < SD < SDth), the PR integration target load PRTL corresponding thereto also becomes zero.

In contrast, as shown in fig. 6B, the PR integrated target load characteristics of the PR integrated target load map 104 in the 2 nd speed region SD2 have the following characteristics: as the diagonal wheel spring upper speed difference SD points to the extension side and becomes larger, the PR integration target load PRTL pointing to the shortening side becomes larger in an infinite geometric progression; on the other hand, as the diagonal wheel on-spring speed difference SD points to the shortened side and becomes larger, the PR integration target load PRTL pointing to the extended side becomes larger in an infinite order of scale.

A predetermined extension-side gain (Ten gain) related to the diagonal wheel spring velocity difference SD is set in the Ten gain setting unit 107. The Ten gain set by the Ten gain setting unit 107 is sent to the selection unit 111.

A predetermined shortening-side gain (Comp gain) related to the diagonal wheel on-spring speed difference SD is set in the Comp gain setting unit 109. The Comp gain set by the Comp gain setting unit 109 is sent to the selection unit 111.

The selection unit 111 selects one piece of information from the Ten gain set by the Ten gain setting unit 107, the Comp gain set by the Comp gain setting unit 109, or the information on the diagonal wheel sprung velocity difference SD according to a predetermined flow. The information selected by the selection unit 111 is sent to the first multiplication unit 113.

The primary multiplying unit 113 multiplies the information selected by the selecting unit 111 by the PR gain set by the PR gain setting unit 103 and the value of the PR integration target load PRTL calculated by the PR integration target load calculating unit 105. The multiplication result of the primary multiplication unit 113 is sent to the secondary multiplication unit 119.

The subtracting unit 115 subtracts the value of the pitch rate PV from the value of the roll rate RV. The difference between the pitch and roll rates (RV-PV), which is the subtraction result of the subtraction unit 115, is sent to the ABS conversion unit 77. When the balance adjustment is performed with respect to the pitch attitude and the roll attitude, the subtraction result (RV-PV) is referred to.

In the following description, the "difference between pitch and roll rate" may be simply referred to as "PR ratio difference".

The ABS conversion unit 77 converts the absolute value of the PR ratio difference (RV-PV) which is the subtraction result of the subtraction unit 115. Information of the ABSPR ratio difference (| RV-PV | ═ ABSPR) after the absolute value conversion by the ABS conversion section 77 (after ABS conversion) is sent to the 3 rd limit ratio calculation section 117.

The 3 rd limit ratio calculation unit 117 calculates a value of the 3 rd limit ratio LR3 corresponding to the ABSPR ratio difference (ABSPR). When calculating the 3 rd limit ratio LR3, the 3 rd limit ratio calculation unit 117 refers to the information of the ABSPR ratio difference (ABSPR) and the 3 rd limit ratio map (see fig. 6C) 116. The 3 rd limit ratio map 116 is a map conceptually showing a relationship of the limit ratio of the electromagnetic actuator 13 with respect to the expansion/contraction control amount that changes in accordance with the ABSPR ratio difference (ABSPR).

The value of the 3 rd limit ratio LR3 calculated by the 3 rd limit ratio calculation unit 117 is sent to the quadratic multiplication unit 119.

Here, the 3 rd limit ratio calculation unit 117 will be described with reference to fig. 6C.

As shown in fig. 6C, the change region of the ABSPR ratio difference (ABSPR) in the 3 rd limit ratio map 116 is composed of two velocity regions in total of the 1 st velocity region PR1 and the 2 nd velocity region PR2 in ascending order with a predetermined velocity threshold PRth interposed therebetween.

The predetermined speed threshold PRth is a threshold for determining which of the pitch rate PV and the roll rate RV is in the priority order (whether or not the balance with respect to the pitch attitude and the roll attitude is lost) in the ABSPR ratio difference (ABSPR) shown on the horizontal axis of fig. 6C.

When the balance relating to the pitch attitude and the roll attitude is lost, the ABSPR ratio difference (ABSPR) takes a value near 0 or near the maximum value on the horizontal axis shown in fig. 6C.

On the other hand, when the balance between the pitch attitude and the roll attitude is maintained, the ABSPR ratio difference (ABSPR) takes a value near the predetermined speed threshold PRth on the horizontal axis shown in fig. 6C.

Therefore, in the 3 rd limit ratio table 116, as shown in fig. 6C, when the balance relating to the pitch posture and the roll posture is lost, the value of the 3 rd limit ratio LR3 takes a value close to the maximum value, that is, (1). On the other hand, when the balance between the pitch posture and the roll posture is maintained, the value of the 3 rd limit ratio LR3 is a value close to the minimum value, that is, (0.5).

The gist of the structure is as follows: increasing a contribution degree of the PR integrated target load PRTL obtained based on the diagonal wheel sprung velocity difference SD to the final target load when the balance associated with the pitch attitude and the roll attitude collapses; when the balance between the pitch attitude and the roll attitude is maintained, the contribution degree of the PR integrated target load PRTL to the final target load based on the diagonal wheel sprung velocity difference SD is reduced.

The quadratic multiplier 119 multiplies the value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculator 79 and the multiplication result by the first multiplier 113 by the value of the 3 rd limit ratio LR3 calculated by the 3 rd limit ratio calculator 117. The multiplication result of the second-order multiplication unit 119 is sent to the third-order multiplication unit 123.

Then, ABS conversion unit 77, to which vehicle speed VS is input, converts vehicle speed VS in absolute value. The information of vehicle speed VS after the absolute value conversion by ABS conversion unit 77 is sent to 4 th limit ratio calculation unit 121.

As shown in fig. 6D, the 4 th limit ratio calculation unit 121 calculates a value of the 4 th limit ratio LR4 according to the vehicle speed VS. When calculating the 4 th limit ratio LR4, the 4 th limit ratio calculator 121 refers to the information of the vehicle speed VS and the 4 th limit ratio map (see fig. 6D) 120. The 4 th limit ratio map 120 is a map conceptually showing a relationship of the limit ratio of the electromagnetic actuator 13 with respect to the expansion/contraction control amount, which varies according to the vehicle speed VS.

The value of the 4 th limit ratio LR4 calculated by the 4 th limit ratio calculator 121 is sent to the cubic multiplier 123.

Here, the 4 th limit ratio table 120 will be described with reference to fig. 6D.

As shown in fig. 6D, the change region of the vehicle speed VS in the 4 th limit ratio table 120 is composed of three speed regions in total, i.e., the 1 st speed region VS1, the 2 nd speed region VS2, and the 3 rd speed region VS3, in ascending order of the vehicle speed VS.

The 1 st speed region VS1 is a speed region when the vehicle speed VS falls below the 1 st speed threshold VSth1(| VS-VSth 1| ≦ 0). The 1 st speed threshold VSth1 is an upper threshold for dividing a low speed region of all the speed regions of the vehicle speed VS.

Both the 2 nd speed region VS2 and the 3 rd speed region VS3 are speed regions when the vehicle speed VS exceeds the 1 st speed threshold VSth1(| VS-VSth 1| > 0) and reaches the medium speed and the high speed, respectively.

On the other hand, as shown in the vertical axis of fig. 6D, a fixed value (0.8), a variable value (0.8 < LR4 < 1), and a fixed value (1) are set as the values of 4 th limit ratio LR4 corresponding to the speed region of vehicle speed VS.

In the example of fig. 6D, each value of vehicle speed VS belonging to 1 st speed range VS1 can be replaced with a fixed value (0.8) of 4 th limit ratio LR 4.

The gist of the configuration is that the characteristic value of the PR integrated target load PRTL calculated by the PR integrated target load calculation unit 105 is subjected to reduction correction and used by performing predetermined limitation based on the 4 th limitation ratio LR4 in the 1 st speed range VS1, which is a range where the vehicle speed VS is relatively low.

For example, each value of vehicle speed VS belonging to 2 nd speed range VS2 is replaced in a one-to-one manner by a value belonging to the range of (0.8 to 1) corresponding to the value of vehicle speed VS, via a predetermined linear function connecting fixed values (0.8) to (1) of 4 th limit ratio LR 4. For example, the 1 st speed threshold VSth1 can be replaced with a fixed value (0.8) of the 4 th limit ratio LR 4. The 2 nd speed threshold value VSth2 can be replaced with a fixed value (1) of the 4 th limit ratio LR 4.

The gist of the configuration is that, in the 2 nd speed range VS2, which is a range in which the vehicle speed VS is relatively moderate, a variable value having a linear characteristic in which the value of the 4 th limit ratio LR4 increases as the vehicle speed VS increases is assigned, and the characteristic value of the PR integration target load PRTL is increased and used as the vehicle speed VS increases.

Further, for example, each value of vehicle speed VS belonging to 3 rd speed range VS3 can be replaced with fixed value (1) of 4 th limit ratio LR 4.

The gist of the configuration is to hold the characteristic value of the PR integrated target load PRTL calculated by the PR integrated target load calculation unit 105 without performing predetermined limitation by the 4 th limitation ratio LR4 in the 3 rd speed range VS3, which is a region where the vehicle speed VS is relatively high, and to use the characteristic value as it is.

The third multiplier 123 multiplies the multiplication result of the second multiplier 119 by the value of the 4 th limiting ratio LR4 calculated by the 4 th limiting ratio calculator 121. The multiplication result of the third-order multiplier 123 is sent to the adder 125.

The adder 125 adds the multiplication result of the secondary multiplier 70 belonging to the pop-up target value calculator 47 to the multiplication result of the tertiary multiplier 123 belonging to the PR aggregate target value calculator 101.

The adder 125 constitutes a part of the "drive controller 45" of the present invention.

The addition result of the addition unit 125, that is, the integrated target load obtained by integrating all the control target values regarding the bounce attitude, the pitch attitude, and the roll attitude is transmitted to the electromagnetic actuators 13 provided on the wheels FL (front left), FR (front right), RL (rear left), and RR (rear right).

[ action of electric suspension device 11B of No. 2 ]

Next, the operation of the 2 nd electric suspension device 11B according to embodiment 2 of the present invention will be described with reference to fig. 7. Fig. 7 is a flowchart for explaining the operation of the 2 nd electric suspension device 11B according to embodiment 2 of the present invention.

In step S21 shown in fig. 7, the information acquisition unit 41 of the 2 nd load control ECU15B acquires information on the sprung mass velocity SV, pitch rate PV, roll rate RV, diagonal wheel sprung mass velocity difference SD, vehicle speed VS, stroke position of the electromagnetic actuator 13, and motor current relating to the electric motor 31, in the same manner as in step S11 shown in fig. 5.

The information acquired by the information acquiring unit 41 is sent to the target load calculating unit 43.

In step S22, the bounce target value calculation unit 47 belonging to the target load calculation unit 43 of the 2 nd load control ECU15B calculates the bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV in the same manner as in step S12 shown in fig. 5. The calculation result of the bounce target value is sent to the addition unit 91.

In step S23, the PR integrated target value calculation unit 101 of the 2 nd load control ECU15B calculates PR integrated target values for suppression control regarding the pitch attitude and the roll attitude of the vehicle 10 based on the diagonal wheel spring velocity difference SD.

Specifically, in the PR integrated target value calculation unit 101, the primary multiplication unit 113 multiplies the information selected by the selection unit 111 by the PR gain set by the PR gain setting unit 103 and the value of the PR integrated target load PRTL calculated by the PR integrated target load calculation unit 105. The multiplication result of the primary multiplication unit 113 is sent to the secondary multiplication unit 119.

The 3 rd limit ratio calculation unit 117 calculates a value of the 3 rd limit ratio LR3 corresponding to the ABSPR ratio difference (ABSPR). The value of the 3 rd limit ratio LR3 calculated by the 3 rd limit ratio calculation unit 117 is sent to the quadratic multiplication unit 119.

The quadratic multiplier 119 multiplies the value of the 1 st limit ratio LR1 calculated by the 1 st limit ratio calculator 79 and the multiplication result by the first multiplier 113 by the value of the 3 rd limit ratio LR3 calculated by the 3 rd limit ratio calculator 117. The multiplication result of the second-order multiplication unit 119 is sent to the third-order multiplication unit 123.

The third multiplier 123 multiplies the multiplication result of the second multiplier 119 by the value of the 4 th limiting ratio LR4 calculated by the 4 th limiting ratio calculator 121. Thus, the PR integrated target value can be obtained by the calculation of the PR integrated target value calculation unit 101. The multiplication result (PR integrated target value) of the third-order multiplication unit 123 is sent to the addition unit 125.

In step S25, the addition unit 125 belonging to the drive control unit 45 of the 2 nd load control ECU15B adds the multiplication result (pop-up target value) of the secondary multiplication unit 70 belonging to the pop-up target value calculation unit 47 to the PR integrated target value obtained by the calculation of the PR integrated target value calculation unit 101. Thereby, an integrated target load obtained by integrating all the control target values regarding the bounce attitude, the pitch attitude, and the roll attitude is calculated.

In step S26, the drive control unit 45 of the 2 nd load control ECU15B executes drive control of the electromagnetic actuator 13 based on the integrated target load calculated in step S25.

According to the 2 nd electric suspension device 11B, by performing drive control of the electromagnetic actuator 13 while taking into account all the control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, it is possible to appropriately suppress a behavior change of the vehicle 10.

[ Effect of the invention on the electric suspension device 11 ]

The electric suspension device 11 according to aspect 1 is premised on an electric suspension device 11 including an actuator (electromagnetic actuator 13) that is provided between a vehicle body and a wheel of a vehicle 10 and generates a damping force for damping vibration of the vehicle body.

The electric suspension device 11 according to claim 1 includes: an information acquisition unit 41 that acquires information on the sprung velocity SV, pitch rate PV, and roll rate RV of the vehicle 10; a bounce target value calculation unit 47 that calculates a bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV; a pitch target value calculation unit 48 that calculates a pitch target value for pitch attitude control of the vehicle 10 based on the pitch rate PV; a roll target value calculation unit 49 that calculates a roll target value for roll attitude control of the vehicle 10 based on the roll rate RV; and a drive control unit 45 that performs drive control of the electromagnetic actuator 13 using a control target load obtained based on a sum of the bounce target value, the pitch target value, and the roll target value.

In the electric suspension device 11 according to point 1, the information acquisition unit 41 acquires information on the sprung velocity SV, pitch rate PV, and roll rate RV of the vehicle 10. The bounce target value calculation unit 47 calculates a bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV. The pitch target value calculation unit 48 calculates a pitch target value for controlling the pitch attitude of the vehicle 10 based on the pitch rate PV. The roll target value calculation unit 49 calculates a roll target value for roll attitude control of the vehicle 10 based on the roll rate RV.

The drive control unit 45 performs drive control of the electromagnetic actuator 13 using a control target load obtained based on a total value of the bounce target value, the pitch target value, and the roll target value.

According to the electric suspension device 11 according to aspect 1, by performing drive control of the electromagnetic actuator 13 while taking into consideration all control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, it is possible to appropriately suppress a behavior change of the vehicle 10.

In the electric suspension device 11 according to viewpoint 2, the pitch target value calculation unit 48 corrects the pitch target value as a result of the calculation based on the information on the sprung mass velocity SV in the electric suspension device 11 according to viewpoint 1. The roll target value calculation unit 49 corrects the roll target value as a result of the calculation based on the information of the sprung velocity SV.

The drive control unit 45 may be configured to perform drive control of the electromagnetic actuator 13 using a control target load obtained based on a sum of the bounce target value and the corrected pitch target value and roll target value.

In the electric suspension device 11 according to viewpoint 2, the correction of the pitch target value as the calculation result by the pitch target value calculation unit 48 based on the information of the sprung mass velocity SV corresponds to the following processing: in the pitch target value calculation unit 48 shown in fig. 4A, the secondary multiplication unit 80 multiplies the multiplication result (pitch target value candidate) of the primary multiplication unit 75 by the value of the 1 st limiting ratio LR1 obtained by the 1 st limiting ratio calculation unit 79 (or the value of the 2 nd limiting ratio LR2 obtained by the 2 nd limiting ratio calculation unit 89).

By correcting the pitch target value based on the information of the sprung velocity SV, the pitch target value can be reduced when the sprung velocity SV is large, for example. As a result, for example, even when the sprung velocity SV is large, it is possible to suppress excessive pitch attitude control.

In the electric suspension device 11 according to aspect 2, the correction of the roll target value as a result of the calculation by the roll target value calculation unit 49 based on the information on the sprung velocity SV corresponds to the following processing: in the roll target value calculation unit 49 shown in fig. 4A, the secondary multiplication unit 90 multiplies the multiplication result (roll target value candidate) of the primary multiplication unit 85 by the value of the 1 st limit ratio LR1 obtained by the 1 st limit ratio calculation unit 79 (or the value of the 2 nd limit ratio LR2 obtained by the 2 nd limit ratio calculation unit 89).

By correcting the roll target value based on the information of the sprung velocity SV, the roll target value can be lowered when the sprung velocity SV is large, for example. As a result, for example, even when the sprung velocity SV is large, it is possible to suppress excessive roll attitude control.

According to the electric suspension device 11 according to aspect 2, since the drive control unit 45 performs the drive control of the electromagnetic actuator 13 using the control target load obtained based on the total value of the bounce target value, the corrected pitch target value, and the roll target value, it is possible to suppress excessive pitch attitude control and roll attitude control even when the sprung mass velocity SV is large, for example, in addition to the operational effects described above with respect to the electric suspension device 11 according to aspect 1.

Further, the electric suspension device 11 according to aspect 3 is based on the premise that the electric suspension device 11 is provided with an actuator (electromagnetic actuator 13) that is provided between the vehicle body and the wheels of the vehicle 10 and generates a damping force for damping vibration of the vehicle body, as in the electric suspension device 11 according to aspect 1.

The electric suspension device 11 according to claim 3 includes: an information acquisition unit 41 that acquires the sprung velocity SV and the diagonal wheel sprung velocity difference SD of the vehicle 10, respectively; a bounce target value calculation unit 47 that calculates a bounce target value for controlling the bounce attitude of the vehicle 10 based on the sprung velocity SV; a pitch target value calculation unit 48 that calculates a pitch target value for pitch attitude control of the vehicle 10 based on the diagonal wheel spring velocity difference SD; a roll target value calculation unit 49 that calculates a roll target value for roll attitude control of the vehicle 10 based on the diagonal wheel sprung velocity difference SD; and a drive control unit 45 that performs drive control of the electromagnetic actuator 13 using a control target load obtained based on a sum of the bounce target value, the pitch target value, and the roll target value.

The electric suspension device 11 according to viewpoint 1 is different from the electric suspension device 11 according to viewpoint 3 mainly in that, in the electric suspension device 11 according to viewpoint 3, the pitch target value calculation unit 48 and the roll target value calculation unit 49 each calculate a pitch target value and a roll target value based on the common diagonal wheel sprung velocity difference SD instead of the individual parameters (pitch rate PV and roll rate RV).

According to the electric suspension device 11 according to aspect 3, similarly to the electric suspension device 11 according to aspect 1, by performing drive control of the electromagnetic actuator 13 while taking into account all the control target values relating to the bounce attitude, the pitch attitude, and the roll attitude, it is possible to appropriately suppress a change in behavior of the vehicle 10.

Further, according to the electric suspension device 11 according to point 3, since the pitch target value calculation unit 48 and the roll target value calculation unit 49 each calculate the pitch target value and the roll target value based on the common diagonal wheel spring velocity difference SD, the configuration can be simplified in terms of reducing the control parameters, as compared with the electric suspension device 11 according to point 1 that requires separate control parameters (pitch rate PV and roll rate RV).

In the electric suspension device 11 according to viewpoint 4, the information acquiring unit 41 further acquires information on the pitch rate PV and the roll rate RV in the electric suspension device 11 according to viewpoint 3. The pitch target value calculation unit 48 corrects the pitch target value as the calculation result based on the information of which the order of priority is given to the pitch rate PV and the roll rate RV. The roll target value calculation unit 49 corrects the roll target value as a result of the calculation based on the information that gives priority to the rank among the pitch rate PV and the roll rate RV.

The drive control unit 45 may be configured to perform drive control of the electromagnetic actuator 13 using a control target load obtained based on a sum of the bounce target value and the corrected pitch target value and roll target value.

In the electric suspension device 11 according to the 4 th aspect, each of the pitch target value calculation unit 48 and the roll target value calculation unit 49 corrects the pitch target value and the roll target value, which are the calculation results, based on the information that gives priority to the order of the pitch rate PV and the roll rate RV.

Here, whether one of the pitch rate PV and the roll rate RV is in the priority order means that the balance relating to the pitch posture and the roll posture is lost. The information with higher priority in the order of the pitch rate PV and the roll rate RV is information with a large influence after the balance of the pitch posture and the roll posture is lost.

According to the electric suspension device 11 according to point 4, since the pitch target value calculation unit 48 and the roll target value calculation unit 49 each correct the pitch target value and the roll target value as the calculation results based on the information of which the order of priority is given to the pitch rate PV and the roll rate RV, it is possible to grasp the behavior change of the vehicle 10 accurately in time in addition to the operational effect of the electric suspension device 11 according to point 3, and to improve the effect of suppressing the behavior change of the vehicle 10 appropriately.

In the electric suspension device 11 according to viewpoint 5, the information acquisition unit 41 also acquires information on the vehicle speed VS of the vehicle 10 in the electric suspension device 11 according to viewpoint 3. The pitch target value calculation unit 48 corrects the pitch target value as the calculation result based on the vehicle speed VS so that the value becomes larger as the vehicle speed VS becomes higher. The roll target value calculation unit 49 corrects the roll target value as a result of the calculation based on the vehicle speed VS so that the value thereof increases as the vehicle speed VS increases.

The drive control unit 45 may be configured to perform drive control of the electromagnetic actuator 13 using a control target load obtained based on a sum of the bounce target value and the corrected pitch target value and roll target value.

In the electric suspension device 11 according to viewpoint 5, the pitch target value calculation unit 48 and the roll target value calculation unit 49 each correct the pitch target value and the roll target value as the calculation results so that their values become larger as the vehicle speed VS becomes higher.

Here, the behavior changes associated with the pitch posture and the roll posture respectively become larger as the vehicle speed VS becomes higher.

Therefore, the pitch target value calculation unit 48 and the roll target value calculation unit 49 correct the pitch target value and the roll target value so that their values become larger as the vehicle speed VS becomes higher, thereby suppressing behavior changes associated with the pitch posture and the roll posture, respectively.

According to the electric suspension device 11 according to aspect 5, since the pitch target value calculation unit 48 and the roll target value calculation unit 49 each correct the pitch target value and the roll target value so that their values become larger as the vehicle speed VS becomes higher, the effect of suppressing the behavior change associated with each of the pitch attitude and the roll attitude can be enhanced in addition to the operational effect of the electric suspension device 11 according to aspect 3.

[ other embodiments ]

The embodiments described above are specific examples of the present invention. Therefore, the technical scope of the present invention should not be construed in a limiting manner by these embodiments. This is because the present invention can be implemented in various ways without departing from the gist or the main feature thereof.

For example, in the description of the electric suspension device 11 according to the present invention, the electromagnetic actuator 13 that converts the rotational driving force of the electric motor 31 in the vertical stroke direction and functions as a component corresponding to the actuator according to the present invention is described as an example, but the present invention is not limited to this example.

As a component corresponding to the actuator of the present invention, for example, a known damping force variable damper of a single tube type (de-carbon type) shown in japanese patent application laid-open No. 2015-47906 may be applied. A piston rod is inserted into a cylindrical hydraulic cylinder filled with MRF (magnetic viscous fluid) so as to be slidable in the axial direction. The piston mounted at the front end of the piston rod divides the interior of the hydraulic cylinder into an upper oil chamber and a lower oil chamber. The piston is provided with a communication passage for communicating the upper oil chamber with the lower oil chamber, and an MLV coil positioned inside the communication passage.

In the description of the electric suspension device 11 according to the present invention, the example shown in fig. 4B is described as the bounce target load characteristic of the bounce target load fig. 52, but the present invention is not limited to this example.

In the present invention, the pop-up target load characteristics of the pop-up target load map 52 are not particularly limited, and desired pop-up target load characteristics may be appropriately adopted.

In the description of the electric suspension apparatus 11 according to the present invention, the example shown in fig. 4C is described as the pitch target load characteristic of the pitch target load map 72, but the present invention is not limited to this example.

In the present invention, the pitch target load characteristic as the pitch target load map 72 is not particularly limited, and a desired pitch target load characteristic may be appropriately adopted.

In the description of the electric suspension device 11 according to the present invention, the example shown in fig. 4D is described as the roll target load characteristic of the roll target load map 82, but the present invention is not limited to this example.

In the present invention, the roll target load characteristic as the roll target load map 82 is not particularly limited, and a desired roll target load characteristic may be appropriately adopted.

In the description of the electric suspension device 11 according to the present invention, the example shown in fig. 6B is described as the PR integrated target load characteristic of the PR integrated target load map 104, but the present invention is not limited to this example.

In the present invention, the PR integrated target load characteristics as the PR integrated target load map 104 are not particularly limited, and desired PR integrated target load characteristics may be appropriately adopted.

In the description of the electric suspension apparatus 11 according to the present invention, the example shown in fig. 4E and 4F is described as the limit ratio characteristic of the 1 st limit ratio table 78, 88, but the present invention is not limited to this example.

In the present invention, the limit ratio characteristics of the 1 st limit ratio tables 78 and 88 are not particularly limited, and desired limit ratio characteristics may be appropriately adopted.

In the description of the electric suspension apparatus 11 according to the present invention, the example shown in fig. 6C is described as the 3 rd limitation ratio characteristic of the 3 rd limitation ratio table 116, but the present invention is not limited to this example.

In the present invention, the 3 rd limit ratio characteristic as the 3 rd limit ratio table 116 is not particularly limited, and a desired limit ratio characteristic may be appropriately adopted.

In the description of the electric suspension apparatus 11 according to the present invention, the example shown in fig. 6D is described as the 4 th limitation ratio characteristic of the 4 th limitation ratio table 120, but the present invention is not limited to this example.

In the present invention, the 4 th limitation ratio characteristic as the 4 th limitation ratio table 120 is not particularly limited, and a desired limitation ratio characteristic may be appropriately adopted.

In the description of the electric suspension device 11 of the present invention, an example in which four electromagnetic actuators 13 are disposed in total on both the front wheels (left and right front wheels) and the rear wheels (left and right rear wheels) is described, but the present invention is not limited to this example. A total of two electromagnetic actuators 13 may be disposed on either the front wheels or the rear wheels.

Finally, in the description of the electric suspension apparatus 11 of the present invention, the drive control unit 45 that independently performs drive control of each of the plurality of electromagnetic actuators 13 is mentioned.

Specifically, the drive control unit 45 may control the driving of the electromagnetic actuators 13 provided for the four wheels independently for each wheel.

The drive control of the electromagnetic actuators 13 provided for the four wheels may be performed independently for each of the front wheel side and the rear wheel side, or may be performed independently for each of the left wheel side and the right wheel side.