JP5652055B2 - Vehicle vibration estimation device and vehicle system vibration control device using the same - Google Patents

Description

  The present invention relates to a vehicle body vibration estimation device for estimating vibration of a vehicle body, for example, pitching vibration and vertical vibration, which is a sprung mass of a vehicle in which wheels are suspended via a suspension device, and vehicle system vibration control using the same. It relates to the device.

  The vehicle body vibration estimation device is useful for vehicle system vibration control using a suspension device and vehicle system vibration control using a braking / driving force. Conventionally, for example, those shown in Patent Documents 1 to 3 are known.

  The vehicle body vibration estimation technique described in Patent Document 1 uses a vehicle body motion model (vehicle model) to estimate the pitching motion and vertical motion of the vehicle body from the braking / driving force based on the operation by the driver.

  In addition, the vehicle body vibration estimation technology described in Patent Documents 2 and 3 estimates the vehicle body vibration from the braking / driving force based on the driver's operation using the vehicle body motion model (vehicle model) as in Patent Document 1. In addition, the disturbance torque input to the vehicle body is estimated from the wheel speed fluctuation, and this disturbance torque is also input to the vehicle body motion model, so that the influence of the disturbance can be estimated and the vehicle body vibration can be estimated more accurately. Is aimed at.

JP 2004-168148 A JP 2009-127456 A JP 2008-179277 A

However, as in the vehicle body vibration estimation technique described in Patent Document 1 described above, when estimating vehicle body vibration using a vehicle body motion model (vehicle model) from the braking / driving force based on the operation by the driver,
If there is a disturbance input due to road surface unevenness or the like, the vehicle body vibration may not be estimated accurately.

Furthermore, as in the vehicle body vibration estimation technology described in Patent Documents 2 and 3, when estimating vehicle body vibration from braking / driving force using a vehicle body motion model (vehicle model), the magnitude of disturbance torque is predicted from wheel speed fluctuations. However, by inputting this disturbance torque into the vehicle body motion model, even if trying to estimate the body vibration more accurately while eliminating the influence of the disturbance,
Each wheel speed fluctuation does not necessarily represent the magnitude of the disturbance torque applied to the wheel, and as a result, the magnitude of the disturbance torque predicted from the wheel speed fluctuation is also inaccurate and the estimation accuracy of the vehicle body vibration based on this is low. This causes the problem.

For example, in the vehicle body vibration estimation technique described in Patent Document 3, the torque applied to the wheel is calculated from the product of the wheel load and the wheel rotational angular velocity, but since the wheel load and the wheel mass are different, The calculation result of such torque is not necessarily correct,
The actual situation is that the original aim of accurately estimating the vehicle body vibration while eliminating the influence of disturbances cannot be achieved.

In order to improve the disturbance robustness, the present invention uses the above-described methods as described in Patent Documents 2 and 3, and as described above, the magnitude of the disturbance torque predicted from the wheel speed fluctuation is inaccurate, In view of the fact that disturbance robustness cannot be improved as intended,
The estimation result by the body vibration estimation technology using the wheel speed physical quantity is used as the observer input of the body motion estimation device (vehicle model) using the vehicle model, and the disturbance body robustness is also estimated by estimating the final body vibration. An object of the present invention is to provide an excellent vehicle body motion estimation device and a vehicle system vibration control device including the vehicle body motion estimation device.

For this purpose, the vehicle body vibration estimation apparatus according to the present invention is configured as follows.
First, to explain the vehicle body vibration estimation device that is the premise of the present invention,
Suspended front wheels via a front wheel suspension device is to estimate the vibration of the vehicle body is sprung mass of the vehicle which is suspended the rear wheel via the rear wheel suspension system.

The present invention is directed to such a vehicle body vibration estimation device.
Front wheel speed physical quantity related to the front wheel speed is a circumferential velocity of the front wheel, and the wheel speed physical quantity detecting means for detecting a wheel speed physical quantity after related to wheel speed after a and the peripheral speed of the rear wheel,
Using the front wheel speed physical quantity and the rear wheel speed physical quantity detected by the means, the correlation between the front wheel longitudinal displacement amount and the vertical displacement amount with respect to the vehicle body determined by the front wheel speed physical amount and the geometric characteristics of the front wheel suspension device. as well as the rear wheel speed physical quantity, and depends on the geometry characteristics of the rear wheel suspension device, the correlation between the longitudinal direction displacement of the rear wheels relative to the vehicle body in the vertical direction displacement amount, the vehicle wheel speed physical quantity reference vehicle body Wheel speed physical quantity reference vehicle body vibration estimation means for estimating vibration,
Braking / driving force detecting means for detecting braking / driving force of the vehicle;
The vehicle body vibration estimated by the wheel speed physical quantity reference vehicle body vibration estimating means is used as an observer input, and the vehicle body vibration is estimated from the vehicle braking / driving force obtained by the braking / driving force detecting means by using a vehicle model. The present invention is characterized in that a braking / driving force reference vehicle body vibration estimation means for providing a vehicle body vibration is provided.

The vehicle system vibration control device of the present invention comprises the vehicle body vibration estimation device described above,
Braking / driving force correction amount calculating means for calculating a braking / driving force correction amount necessary for reducing the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimating means;
There is provided braking / driving force correcting means for correcting the braking / driving force of the vehicle by the braking / driving force correction amount obtained by the means.

According to the above-described vehicle body vibration estimation device of the present invention, the front wheel speed physical quantity, the correlation between the front wheel longitudinal displacement amount and the vertical displacement amount with respect to the vehicle body, the rear wheel speed physical quantity, and the rear wheel with respect to the vehicle body. Estimate wheel speed physical quantity based vehicle body vibration from the correlation between the longitudinal displacement amount and the vertical displacement amount of
While this wheel speed physical quantity standard vehicle body vibration is used as an observer input, the braking / driving force standard vehicle body vibration is estimated from the vehicle braking / driving force using the vehicle model to obtain the final vehicle body vibration. .

First, the front wheel speed physical quantity and the front wheel front-rear displacement with respect to the vehicle body are used without using torque or force that changes according to deterioration over time or increase / decrease in the number of passengers, such as spring constant and vehicle mass, as in the past. Estimate wheel speed physical quantity based vehicle body vibration from the correlation between the vertical displacement amount, the rear wheel speed physical amount, and the correlation between the front wheel longitudinal displacement amount and the vertical displacement amount with respect to the vehicle body. Accuracy can be increased.
Furthermore, in order to estimate the braking / driving force reference vehicle body vibration (final vehicle body vibration) using the vehicle model from the braking / driving force of the vehicle while using this highly accurate wheel speed physical quantity reference vehicle body vibration as an observer input,
The braking / driving force reference vehicle body vibration (final vehicle body vibration) can be made highly accurate with excellent disturbance robustness.

In addition, if the wheel speed physical quantity reference vehicle body vibration is used as the final vehicle body vibration as it is, the wheel speed physical quantity reference vehicle body vibration is after the vehicle body vibration has occurred. , Final vehicle vibration estimation is too slow and unsuitable,
In the vehicle body vibration estimation device according to the present invention, the braking / driving force reference body vibration estimated using the vehicle model from the braking / driving force of the vehicle before the vehicle body vibration is generated, while using the wheel speed physical quantity reference vehicle body vibration as an observer input. In order to use vibration, even when the vehicle system vibration control is feedforward control, the final estimation of the vehicle body vibration is not too late.

The vehicle system vibration control device according to the present invention includes the above-described vehicle body vibration estimation device, and calculates a braking / driving force correction amount necessary to reduce the estimated final vehicle body vibration. In order to correct the braking / driving force of the vehicle by the driving force correction amount,
Coupled with the fact that the final vehicle body vibration estimated as described above is highly accurate with excellent disturbance robustness, the vehicle body vibration can always be reduced as intended.

1 is a schematic system diagram showing a vehicle system vibration control system for a vehicle including a vehicle body vibration estimation device according to a first embodiment of the present invention. FIG. 2 is a functional block diagram of the motor controller in FIG. FIG. 3 is a functional block diagram of the vehicle system vibration control calculation unit in FIG. 4 is a flowchart showing a control program executed by a vehicle body vibration estimation unit and a braking / driving torque correction amount calculation unit in FIGS. 2 and 3 to calculate a torque correction amount for estimating vehicle body vibration and suppressing the vehicle body vibration. . FIG. 5 is a vehicle specification explanatory diagram showing a relationship between a vertical bounce motion Zv and a pitching motion θp at the center of gravity of the vehicle body, a vertical displacement Zf at a position above the front axis of the vehicle body, and a vertical displacement Zr at a position above the rear axis of the vehicle body. FIG. 6 is a characteristic diagram showing a front wheel suspension geometry characteristic showing a relationship between a longitudinal displacement amount and a vertical displacement amount related to a front wheel of the vehicle in FIG. FIG. 6 is a characteristic diagram showing a rear wheel suspension geometry characteristic showing a relationship between a longitudinal displacement amount and a vertical displacement amount relating to a rear wheel of the vehicle in FIG. It is explanatory drawing for demonstrating the motion model of a vehicle. FIG. 2 is a schematic system diagram showing a vehicle body vibration estimation process and a vehicle system vibration control process according to the first embodiment of the present invention. FIG. 4 is a functional block diagram of a vehicle body vibration control calculation unit corresponding to FIG. 3, showing a vehicle body vibration estimation device and a vehicle body vibration control device according to a second embodiment of the present invention. The vehicle body vibration estimation unit and the braking / driving torque correction amount calculation unit in FIG. 10 execute a control program for estimating the vehicle body vibration and calculating the braking / driving torque correction amount necessary for suppressing the vehicle body vibration. FIG. 5 is a flowchart corresponding to FIG.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
<Configuration of the first embodiment>
FIG. 1 is a schematic system diagram showing a vehicle body vibration control system for a vehicle including a vehicle body vibration estimation apparatus according to a first embodiment of the present invention.
In FIG. 1, 1FL and 1FR indicate left and right front wheels, respectively, and 1RL and 1RR indicate left and right rear wheels, respectively.
The left and right front wheels 1FL and 1FR are steered wheels steered by the steering wheel 2.
The left and right front wheels 1FL and 1FR and the left and right rear wheels 1RL and 1RR are respectively suspended from the vehicle body 3 by a suspension device (not shown), and the vehicle body 3 is positioned above the suspension device and constitutes a sprung mass.

The vehicle in FIG. 1 is a front-wheel drive electric vehicle that can travel by driving left and right front wheels 1FL and 1FR via a transmission 5 including a differential gear device by a motor 4 as a rotating electric machine.
When the motor 4 is controlled, the motor controller 6 converts the electric power of the battery (capacitor) 7 from DC to AC by the inverter 8 and supplies the AC power to the motor 4 under the control of the inverter 8. It is assumed that the motor 4 is controlled so that the torque of 4 matches the motor torque command value tTm.

If the motor torque command value tTm has a negative polarity that requires the motor 4 to perform a regenerative braking action, the motor controller 6 applies a power generation load to the motor 4 via the inverter 8 so that the battery 7 is not overcharged. Give,
At this time, the electric power generated by the regenerative braking action by the motor 4 is AC-DC converted by the inverter 8 to charge the battery 7.

The motor controller 6 performs vehicle body vibration estimation calculation, which will be described in detail later, and performs vehicle body vibration control calculation for determining the motor torque command value tTm so as to suppress the vehicle body vibration that is the estimation result.
For these calculations, the motor controller 6
Wheel speed sensors 11FL, 11FR that individually detect front wheel speeds VwFL, VwFR, which are the peripheral speeds of left and right front wheels 1FL, 1FR, and rear wheel speeds VwRL, VwRR, which are peripheral speeds of left and right rear wheels 1RL, 1RR, are detected individually. The wheel speed sensors 11RL and 11RR
A signal from the accelerator opening sensor 13 for detecting the accelerator opening APO (accelerator pedal depression amount);
A signal from the brake pedal depression force sensor 14 for detecting the brake pedal depression force BRP,
The gear ratio information from the transmission 5 is input.

In this embodiment, the front wheel speeds VwFL and VwFR themselves are used as physical quantities representing the peripheral speeds of the left and right front wheels 1FL and 1FR, and the rear wheel speeds VwRL and VwRR themselves are used as physical quantities representing the peripheral speeds of the left and right rear wheels 1RL and 1RR. But
The present invention is not limited to these, and it goes without saying that the peripheral speed of the corresponding wheel may be obtained from the rotational speed of any part that rotates together with the left and right front wheels 1FL and 1FR and the left and right rear wheels 1RL and 1RR.

Accordingly, the wheel speed corresponds to the wheel speed physical quantity in the present invention, and the front wheel speed and the rear wheel speed correspond to the front wheel speed physical quantity and the rear wheel speed physical quantity in the present invention, respectively.
The wheel speed sensors 11FL, 11FR, 11RL, and 11RR constitute wheel speed physical quantity detection means in the present invention.

The motor controller 6 estimates the vibration of the vehicle body 3 based on the above input information and corrects the driver's required torque (which will be described later with a sign of dTm ) so as to suppress the estimated vibration of the vehicle body 3. Then, the motor torque command value tTm is determined.

Therefore, the motor controller 6 is generally composed of a vehicle speed calculation unit 20, a required torque calculation unit 21, a vehicle system vibration control calculation unit 22, a motor torque command value calculation unit 23, as generally shown in the block diagram of FIG. , And an adder 24.
The vehicle speed calculation unit 20 includes front wheel speeds VwFL, VwFR and rear wheel speeds VwRL, VwRR detected by wheel speed sensors 11FL, 11FR, 11RL, 11RR (shown as wheel speed sensor group 11 in FIG. 2). The vehicle speed VSP is obtained based on the wheel speed Vw).

The requested torque calculation unit 21 drives the driver at the current vehicle speed VSP from the vehicle speed VSP obtained by the calculation unit 20 and the accelerator opening APO and the brake pedal depression force BRP detected by the sensors 13 and 14, respectively. The requested torque dTm (positive is driving torque, negative is braking torque) requested by the operation (accelerator opening APO and brake pedal depression force BRP) is calculated by map search or the like.
Therefore, the required torque calculation unit 21 constitutes the braking / driving force detection means in the present invention.

The vehicle system vibration control calculation unit 22 includes a vehicle body vibration estimation unit 25 and a braking / driving torque correction amount calculation unit 26.
In the vehicle body vibration estimation unit 25, the vibration of the vehicle body 3 is estimated from the wheel speed Vw and the required torque dTm in detail,
The braking / driving torque correction amount calculation unit 26 calculates a braking / driving torque correction amount ΔTm necessary for suppressing the estimated vehicle body vibration.
The vehicle body vibration estimation unit 25 constitutes wheel speed physical quantity reference vehicle body vibration estimation means and braking / driving force reference vehicle body vibration estimation means in the present invention, as will be described in detail later.
The braking / driving torque correction amount calculation unit 26 constitutes a braking / driving force correction amount calculation means according to the present invention, as will be apparent from the process described in detail later.

Adder 24, the required torque dTm of the driver calculated in the calculating portion 21, and corrected by addition of the braking and driving torque correcting amount calculator system for 26 obtained the vehicle body vibration suppression drive torque correction quantity? Tm, the vehicle body vibration The target torque cTm that satisfies the driver's request is obtained while suppressing.
Therefore, the adder 24 constitutes the braking / driving force correcting means in the present invention.
The motor torque command value calculation unit 23 is supplied from other systems 27 such as a behavior control device (VDC) for controlling vehicle behavior and a traction control device (TCS) for preventing drive slip of the drive wheels (front wheels) 1FL and 1FR. Upon receiving a torque request, the target motor torque command value tTm for realizing this is obtained by limiting or adjusting the target torque cTm so as to satisfy this request.

  The motor controller 6 supplies the electric power from the battery 7 to the motor 4 under the control of the inverter 8 according to the motor torque command value tTm obtained as described above, so that the torque of the motor 4 becomes the motor torque command value tTm. The motor 4 is driven and controlled to match.

<Body vibration estimation and vehicle system vibration control>
The vehicle body vibration estimation unit 25 and the braking / driving torque correction amount calculation unit 26 inside the vehicle system vibration control calculation unit 22 are each configured as shown in the block diagram of FIG. 3, and execute the control program of FIG. 3 (in this embodiment, the pitch angle fθp, the pitch angular velocity dfθp, the bounce amount fZp that is the vertical displacement amount, and the bounce velocity dfZp that is the vertical displacement velocity) are estimated, and this estimated vehicle body vibration (fθp, dfθp, fZp, calculates a braking drive torque correction quantity ΔTm needed to suppress dfZp).

As clearly shown in FIG. 3, the vehicle body vibration estimation unit 25 includes a wheel speed reference vehicle body vibration estimator 25a (wheel speed physical quantity reference vehicle body vibration estimation means in the present invention) and a braking / driving force reference vehicle body vibration estimator 25b (control device in the present invention). Driving force reference vehicle body vibration estimation means),
First, in step S41 of FIG. 4, and as shown in FIG. 3, the wheel speed reference vehicle body vibration estimator 25a reads the left and right front wheel speeds VwFL, VwFR and the left and right rear wheel speeds VwRL, VwRR.

As shown in FIG. 3, the wheel speed reference vehicle body vibration estimator 25a includes an average front wheel speed calculation unit 31, an average rear wheel speed calculation unit 32, a front wheel band pass filter processing unit 33, and a rear wheel band pass filter processing unit 34. The bounce behavior calculation unit 35 and the pitching behavior calculation unit 36 are configured.
3 calculates an average front wheel speed VwF = (VwFL + VwFR) / 2 from the left and right front wheel speeds VwFL and VwFR, and calculates the left and right rear wheels in the average front wheel speed calculation unit 31 and the average rear wheel speed calculation unit 32 (step S42 in FIG. 4). The average rear wheel speed VwR = (VwRL + VwRR) / 2 is calculated from the wheel speeds VwRL and VwRR.

  Next, components in the vicinity of the vehicle body resonance frequency from the average front wheel speed VwF and the average rear wheel speed VwR in the front wheel band pass filter processing unit 33 and the rear wheel band pass filter processing unit 34 (step S43 in FIG. 4) in FIG. The average front wheel speed VwF and the average rear wheel speed VwR are respectively passed through a bandpass filter for extracting and extracting only the vibration component fVwF of the average front wheel speed VwF and the vehicle body resonance frequency of the average rear wheel speed VwR. Get the vibration component fVwR.

  The reason why only the vibration components fVwF and fVwR near the vehicle body resonance frequency are extracted from the average front wheel speed VwF and the average rear wheel speed VwR by filtering is that the wheel speed fluctuation and noise components due to acceleration / deceleration of the entire vehicle are extracted from the average front wheel speed VwF. This is because it is removed from the average rear wheel speed VwR and only the wheel speed component representing the vehicle body vibration is extracted.

  Next, in the bounce behavior calculating unit 35 and the pitching behavior calculating unit 36 (step S44 in FIG. 4) in FIG. 3, the vehicle body having the vibration component fVwF near the vehicle body resonance frequency of the average front wheel speed VwF and the vehicle body having the average rear wheel speed VwR as follows. From the vibration component fVwR near the resonance frequency, the vertical bounce speed dZv and the pitch angular speed dθp of the vehicle body 3, which are wheel speed reference vehicle body vibrations, are obtained.

A method for obtaining the wheel speed reference vehicle body vibration (the bounce speed dZv and the pitch angular speed dθp of the vehicle body 3) from the wheel speed vibration components fVwF and fVwR will be described below.
FIG. 5 shows the vertical bounce motion Zv and pitching motion θp at the center of gravity of the vehicle body 3 and the pitching motion θp at the center of gravity of the vehicle body 3 in a vehicle in which the center-of-gravity point-front axis distance is Lf and 4 schematically shows the relationship between a vertical displacement Zf at a location above the front axis and a vertical displacement Zr at a location above the rear axis of the vehicle body 3.

As shown in this figure, when the vertical displacement Zv and the pitch angle θp are generated in the vehicle body 3, vertical displacements Zf and Zr are also generated in the front shaft upper portion and the rear shaft upper portion of the vehicle body 3, respectively, and these Zv, θp, Zf Therefore, the following relationship is established between Zr.
Zf ＝ Zv ＋ θp ・ Lf (1)
Zr = Zv−θp ・ Lr (2)

Here, when considering the range of motion of the front wheels 1FL, 1FR and the rear wheels 1RL, 1RR in the vertical direction and the front-rear direction with respect to the vehicle body 3, these ranges of motion are the link structures constituting the respective suspension devices, that is, the respective suspensions. It depends on the geometrical constraints depending on the geometry.
Therefore, when the vehicle body 3 and the front wheels 1FL, 1FR are relatively moved in the vertical direction indicated by Zf, the vehicle body 3 and the front wheels 1FL, 1FR are also relatively displaced in the longitudinal direction indicated by Xtf, for example, with the relationship shown in FIG. Also,
When the vehicle body 3 and the rear wheels 1RL and 1RR are relatively moved in the vertical direction indicated by Zr, the vehicle body 3 and the rear wheels 1RL and 1RR are also relatively displaced in the longitudinal direction indicated by Xtr, for example, with the relationship shown in FIG.

That is, the front wheels 1FL, 1FR representing the vehicle vibration are derived from the front wheel speed vehicle body resonance frequency vicinity vibration component fVwF and the rear wheel speed vehicle body resonance frequency vicinity vibration component fVwR obtained by extracting only the wheel speed component representing the vehicle body vibration as described above. If the front-rear direction displacement Xtf and the front-rear direction displacement Xtr of the rear wheels 1RL, 1RR representing the vehicle body vibration are obtained and monitored, the relationship between FIGS. The vertical displacements Zf and Zr can be predicted, respectively.
The bounce behavior calculator 35 and the pitching behavior calculator 36 (step S44 in FIG. 4) for predicting the vertical displacements Zf and Zr correspond to the front wheel vertical motion estimator and the rear wheel vertical motion estimator in the present invention. To do.

  The front wheel suspension geometry characteristics in FIG. 6 and the rear wheel suspension geometry characteristics in FIG. 7 are mapped and stored as they are, or modeled in advance, so that the front wheel longitudinal displacement Xtf and the rear wheel longitudinal displacement The prediction of the vertical displacements Zf and Zr at the front shaft upper part and the rear shaft upper part of the vehicle body 3 from Xtr may be made accurately, so that the vertical displacements Zf and Zr can be accurately predicted.

  However, in this example, from the viewpoint of cost, the gradient KgeoF near the balance point (the origin of FIGS. 6 and 7) when the vehicle is stationary on a flat ground and 1G acceleration is applied (in the case of FIG. 6) ) And KgeoR (in the case of FIG. 7), and these KgeoF and KgeoR are used as proportional coefficients.

When these proportional coefficients KgeoF and KgeoR are used, the relationship between the longitudinal displacement Xtf and the vertical displacement Zf related to the front wheel, and the longitudinal displacement Xtr and the vertical displacement Zr related to the rear wheel are respectively expressed by the following relationships: Is established.
Zf ＝ KgeoF ・ Xtf (3)
Zr ＝ KgeoR ・ Xtr (4)

Solving the above four simultaneous equations, the vertical bounce motion of the vehicle body 3 that is the basis of vehicle vibration (vertical bounce velocity dZv, pitch angular velocity dθp) from the front wheel longitudinal displacement Xtf and the rear wheel longitudinal displacement Xtr. The following equations used to determine Zv and pitching motion θp can be obtained.
θp = (KgeoF · Xtf−KgeoR · Xtr) / (Lf + Lr) (5)
Zv = (KgeoF / Xtf / Lf + KgeoR / Xtr / Lr) / (Lf + Lr) (6)

Then, by differentiating both sides of the above equation with respect to time, the following equations used to obtain the vertical bounce speed dZv and pitch angular velocity dθp of the vehicle body 3, which are wheel speed reference vehicle body vibrations, can be obtained.
However, “d” is a differential operator used simply.
dθp = (KgeoF · dXtf−KgeoR · dXtr) / (Lf + Lr) (7)
dZv = (KgeoF · dXtf · Lf + KgeoR · dXtr · Lr) / (Lf + Lr) (8)

  From these formulas, the vertical bounce speed dZv and the pitch angular speed dθp of the vehicle body 3, which are wheel speed reference vehicle body vibrations, are determined by the bandpass filter processing units 33 and 34 in FIG. 3 (step S43 in FIG. 4) as described above. From the front wheel speed vehicle body resonance frequency vicinity vibration component fVwF and the rear wheel speed vehicle body resonance frequency vicinity vibration component fVwR obtained by extracting only the wheel speed component representing vibration, the longitudinal displacement Xtf of the front wheels 1FL, 1FR representing the vehicle body vibration, Further, the longitudinal displacements Xtr of the rear wheels 1RL, 1RR representing the vehicle body vibration are respectively obtained, and the time differential values dXtf, dXtr of the longitudinal displacements Xtf, Xtr are substituted into the above equations (7) and (8). Thus, the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) can be calculated and estimated, respectively.

While the estimation of the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is performed as described above, the braking / driving force reference vehicle body vibration estimator 25b of FIG. 3 performs step S45 of FIG. The required torque dTm obtained by the calculation unit 21 is read as the braking / driving torque of the vehicle.

The braking / driving force reference vehicle body vibration estimator 25b includes a vehicle model 37 as shown in FIG. 3. In step S46 of FIG. 4, the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is used as an observer input. On the other hand, by estimating the state by the observer using the vehicle model 37 from the required torque dTm (vehicle braking / driving torque), the braking / driving force based vehicle body vibration (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch (Angular velocity dfθp) is calculated and estimated.

FIG. 8 shows a basic vehicle model 37 that constitutes the observer. As described above with reference to FIG. 5, the distance between the center of gravity and the front axis of the wheel base L is Lf, and the distance between the center of gravity and the rear axis. Lr, the spring constant and vibration damping coefficient of the front wheel suspension device are Ksf and Cf, respectively, the spring constant and vibration damping coefficient of the rear wheel suspension device are Ksr and Cr, respectively, and the mass of the vehicle body 3 is M When the braking / driving torque dTm is given to a vehicle having a pitching inertia moment of the vehicle body 3 of Ip,
The braking / driving force reference vehicle body vibration (vertical bounce amount fZv and pitch angle fθp) at the center of gravity of the vehicle body 3 is shown together with the vertical displacement Zf at the position above the front axis of the vehicle body 3 and the vertical displacement Zr at the position above the rear axis of the vehicle body 3. Is.

In the vehicle model of FIG. 8, the equation of motion related to the braking / driving force reference vehicle body vibration (vertical bounce amount fZv and pitch angle fθp) is expressed as follows when the differential operator is simply expressed as “d”.
M · ddfZv = -2Ksf (fZv + Lf · fθp)-2Cf (dfZv + Lf · dfθp)
-2Ksr (fZv-Lr · fθp) -2Cr (dfZv-Lr · dfθp) (9)
Ip · ddfθp = -2Lf {Ksf (fZv + Lf · fθp) + Cf (dfZv + Lf · dfθp)}
+ 2Lr {Ksr (fZv-Lr · fθp) + Cr (dfZv-Lr · dfθp)} + dTm (10)

By converting these equations of motion into a state equation and giving braking / driving torque dTm as an input, pitching motion (pitch angle fθp and pitch angular velocity dfθp) and vertical bounce motion (vertical motion) The bounce amount fZv and the vertical bounce speed dfZv) can be calculated and estimated.
However, the estimation accuracy is low due to modeling errors, disturbances (road surface unevenness), and the like.

Therefore, in the present embodiment, the braking / driving force reference vehicle body vibration estimator 25b in FIG. 3 performs the state by the observer using the vehicle model 37 from the required torque dTm (vehicle braking / driving torque) in step S46 in FIG. When estimating and calculating the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp),
As shown in FIG. 3, the vehicle model 37 is used from the required torque dTm (braking / driving torque of the vehicle) while the wheel speed reference vehicle body vibration (vertical bounce velocity dZv and pitch angular velocity dθp) from the calculation units 35 and 36 is also input as an observer. Thus, the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) is calculated.

Thus, the vehicle model from the required torque dTm (vehicle braking / driving torque) using the braking / driving force reference vehicle vibration estimator 25b of FIG. 3 with the wheel speed reference vehicle vibration (vertical bounce speed dZv and pitch angular speed dθp) as observer inputs. By calculating the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) based on 37,
The disturbance robustness and stability of the braking / driving force reference vehicle body vibration estimator 25b (vehicle model 37) can be made compatible.
In addition, since the braking / driving force reference vehicle body vibration x is estimated from the required torque dTm (vehicle braking / driving torque) that is the cause of the vehicle body vibration, the braking / driving force reference vehicle body vibration is generated not before the vehicle body vibration is generated but before it occurs. x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) can be estimated in a feed-forward manner as the final vehicle body vibration.

In step S47 of FIG. 4, the braking / driving torque correction amount calculation unit 26 of FIG. 3 performs braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, the braking and driving torque correction amount ΔTm required to inhibit the pitch angular velocity Dfshitapi) is calculated as follows.
That is, the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) is multiplied by a regulator gain Kr indicated by 38 in FIG. The resulting linear sum of multiplication values is set as a braking / driving torque correction amount ΔTm .

  At that time, the regulator gain Kr is determined by weighting the degree of suppression (reduction) for each of the final body vibrations, the vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp. The degree may increase.

In addition, the regulator gain Kr is a plurality of regulators set by changing the weighting pattern of the suppression (reduction) degree for each vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp, that is, for each type of vehicle body vibration. Composed of gain,
These and a plurality of regulators gain, vertical bounce amount FZV, vertical bounce rate DfZv, may be used as the pitch angle Fshitapi, and pitch angular velocity dfθp braking and driving torque correction amount the sum of the integrated values of the? Tm.

In addition, the tuning gains for the multiple regulator gains are set, and the total sum of the integrated values of the vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp, multiple regulator gains, and tuning gains is controlled. The driving torque correction amount ΔTm may be used.

The braking / driving torque correction amount ΔTm obtained as described above by the braking / driving torque correction amount calculation unit 26 (step S47 in FIG. 4) in FIG. 3 is supplied to the adder 24 in FIG.
The adder 24, the required torque dTm of the driver by the operation unit 21 was determined to as the corrected only body vibration suppressing braking and driving torque correction amount? Tm, satisfying the requirements of the driver while suppressing the vehicle body vibration Determine the target torque cTm .
The motor torque command value calculation unit 23 in FIG. 2 limits the above target torque cTm so as to meet the torque request from the other system 27, or increases or decreases the final motor torque command value for realizing this. tTm is obtained and contributes to drive control of the motor 4 via the inverter 8.

The flow of vehicle body vibration estimation and vehicle system vibration control of this embodiment described above is as shown in FIG.
A, B, C, and D in FIG. 9 indicate A, B, C, and D matrices when the vehicle model shown in FIG. 8 is expressed by a state equation, and Ko is an observer input (dZv, dθp, dfZv, This represents the observer gain for dfθp).

<Effects of the first embodiment>
As described above, according to the vehicle system vibration control of the present embodiment, the motor 4 suppresses the vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) while requiring the driver's torque. The drive will be controlled to satisfy dTm .
Control of vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) can improve riding comfort as well as control the vehicle body posture when turning the vehicle. Stability can also be improved.

Moreover, according to the present embodiment, when estimating the vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) for the above-described vehicle system vibration control,
The planned correlation illustrated in Figs. 6 and 7 between the longitudinal displacements Xtf, Xtr and the vertical displacements Zf, Zr of the front wheels 1FL, 1FR and rear wheels 1RL, 1RR with respect to the vehicle body 3 (suspension geometry characteristics) Based on the vehicle body resonance frequency vicinity vibration component fVwF of the average front wheel speed VwF and the vehicle body resonance frequency vicinity vibration component fVwR of the average rear wheel speed VwR, the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is estimated,
This wheel speed reference body vibration (vertical bounce speed dZv and pitch angular speed dθp) is used as an observer input, and braking / driving force reference body vibration x (vertical bounce) using the vehicle model 37 from the required drive torque dTm (vehicle braking / driving force). In order to obtain the final vehicle body vibration by estimating the amount fZv, the vertical bounce speed dfZv, the pitch angle fθp, and the pitch angular speed dfθp, the following effects can be obtained.

  First, it is possible to estimate the final vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) without adding a suspension stroke sensor as in the past. Is advantageous.

  In addition, without using torque or force that changes according to deterioration over time or increase / decrease in the number of passengers, such as spring constant and vehicle mass, the vehicle body of the average front wheel speed VwF near the vehicle body resonance frequency fVwF and the average rear wheel speed VwR Since the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is estimated from the vibration component fVwR in the vicinity of the resonance frequency, that is, information related to the wheel speed, the estimation accuracy can be improved.

Furthermore, using this vehicle model 37 from the required drive torque dTm (vehicle braking / driving force) while using this highly accurate wheel speed reference vehicle body vibration (vertical bounce velocity dZv and pitch angular velocity dθp) as an observer input, In order to estimate the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) that is vibration,
This braking / driving force reference vehicle body vibration (final vehicle body vibration) x can be made highly accurate with excellent disturbance robustness, and the effect of the vibration suppression control can be made remarkable.

Also, if the wheel speed reference body vibration (vertical bounce speed dZv and pitch angular speed dθp) is used as the final body vibration, the wheel speed reference body vibration (vertical bounce speed dZv and pitch angular speed dθp) is Therefore, when the vehicle system vibration control is feedforward control, the estimation of the final vehicle body vibration is too slow to be suitable.
In the vehicle body vibration estimation apparatus of the present embodiment, the vehicle speed is estimated using the vehicle model 37 from the braking / driving force dTm of the vehicle before the vehicle body vibration is generated, while the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is input as an observer. The vehicle body vibration control is fed as in this embodiment in order to set the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angle speed dfθp) as the final vehicle body vibration. Even in the case of forward control, the estimation of the final vehicle body vibration is not too late.

In the vehicle system vibration control device of this embodiment, the braking / driving force correction amount ΔTm necessary for reducing the final vehicle body vibration x estimated as described above is calculated, and this braking / driving force correction amount is calculated. In order to correct the braking / driving force dTm of the vehicle by ΔTm ,
Coupled with the estimated final vehicle body vibration x being highly accurate with excellent disturbance robustness for the reasons described above, the vehicle body vibration can always be reduced as intended.

  Note that the front wheel suspension geometry characteristics in FIG. 6 and the rear wheel suspension geometry characteristics in FIG. 7 are mapped and stored as they are, or modeled in advance, and these maps or models are used to change the front wheel longitudinal displacement Xtf. It is advantageous in terms of the prediction accuracy of the vertical displacements Zf and Zr to predict the vertical displacements Zf and Zr at the front shaft upper part and the rear shaft upper part of the vehicle body 3 from the longitudinal displacement Xtr of the rear wheel and the rear wheel, respectively. , It becomes disadvantageous in terms of cost.

  However, in the present embodiment, considering the general driving, the balance point in the state where the vehicle is stationary on the flat ground and the acceleration of 1G is applied (from the viewpoint that it is not necessary to cover the entire suspension stroke. A linear approximation is performed with the gradients KgeoF (in the case of FIG. 6) and KgeoR (in the case of FIG. 7) near the origin of FIGS. Since the vertical displacements Zf and Zr at the front shaft upper portion and the rear shaft upper portion of the vehicle body 3 are predicted from the front wheel longitudinal displacement Xtr, respectively, this is advantageous in terms of cost.

  Further, in this embodiment, the front wheel suspension geometry characteristics of FIG. 6 and the rear wheel suspension geometry characteristics of FIG. 7 are used separately, and the front axle of the vehicle body 3 is determined from the front wheel longitudinal displacement Xtf and the rear wheel longitudinal displacement Xtr. Since the vertical displacements Zf and Zr at the upper part and the rear shaft upper part are individually predicted, the vertical displacements Zf and Zr are accurately predicted, and the vehicle body vibration can be estimated with high accuracy.

Further, in this embodiment, when estimating the wheel speed reference vehicle body vibration (dZv, dθp), the vehicle body resonance frequency vicinity vibration component fVwF extracted from the average front wheel speed VwF and the vehicle body resonance frequency vicinity vibration component fVwR extracted from the average rear wheel speed VwR. From using
Wheel speed reference car body vibration (dZv, dθp) is estimated using only wheel speed information associated with car body vibration, which does not include wheel speed fluctuations and noise components due to acceleration / deceleration of the entire vehicle. Can be done.

<Second embodiment>
10 and 11 show a vehicle body vibration estimation device and a vehicle system vibration control device according to a second embodiment of the present invention, FIG. 10 is a block diagram corresponding to FIG. 3, and FIG. 11 corresponds to FIG. This is a vehicle vibration estimation and vehicle vibration control program.
Also in this embodiment, the vehicle system vibration control system is the same as in FIG. 1, and the motor controller 6 is the same as in FIG. Description of 6 is omitted here, and only differences from the first embodiment will be described below with reference to FIGS.

  In this embodiment, the vehicle body vibration estimation unit 25 in the vehicle system vibration control calculation unit 22 is configured as shown in the block diagram of FIG. 10, and the vehicle body vibration estimation unit 25 executes the control program of FIG. The vibration of the vehicle body 3 (the pitch angle fθp, the pitch angular velocity dfθp, the vertical bounce amount fZp, and the vertical bounce velocity dfZp) is estimated as in the first embodiment.

First, in step S61 in FIG. 11, the vehicle body vibration estimation unit 25 reads the left and right front wheel speeds VwFL and VwFR and the left and right rear wheel speeds VwRL and VwRR as shown in FIG.
Next, in the average front wheel speed calculator 51 and the average rear wheel speed calculator 52 (step S62 in FIG. 11), the average front wheel speed VwF = (VwFL + VwFR) / 2 is calculated from the left and right front wheel speeds VwFL, VwFR, The average rear wheel speed VwR = (VwRL + VwRR) / 2 is calculated from the left and right rear wheel speeds VwRL and VwRR.

  Next, in the bounce behavior calculation unit 53 of FIG. 10 (step S63 of FIG. 11), the longitudinal displacement Xtf of the front wheels 1FL and 1FR relative to the vehicle body from the average front wheel speed VwF and the average rear wheel speed VwR (see FIG. 5), and Then, the longitudinal displacement Xtr (see FIG. 5) of the rear wheels 1RL and 1RR is obtained, and the vertical bounce amount Zv of the vehicle body 3 is calculated by the above formula (6) using the longitudinal displacements Xtf and Xtr of these front and rear wheels (see FIG. 5). (Refer to Fig. 4), and time differential of this to obtain the vertical bounce speed aZv of the vehicle body 3.

  In the pitching behavior calculation unit 54 in FIG. 10 (step S63 in FIG. 11), the longitudinal displacement Xtf (see FIG. 5) of the front wheels 1FL and 1FR relative to the vehicle body from the average front wheel speed VwF and the average rear wheel speed VwR, and the rear wheels The longitudinal displacement Xtr (see Fig. 5) of 1RL and 1RR is obtained, and the pitching motion θp (see Fig. 5) of the vehicle body 3 is obtained by the calculation of the above equation (5) using the longitudinal displacements Xtf and Xtr of these front and rear wheels. This is time differentiated to determine the pitch angular velocity aθp of the vehicle body 3.

Next, in the band pass filter processing unit 55 (step S64 in FIG. 11) in FIG. 10, the vehicle body 3 near the vehicle body resonance frequency is calculated from the vertical bounce speed aZv of the vehicle body 3 obtained by the bounce behavior calculation unit 53 (step S63 in FIG. 11). The vertical bounce speed aZv is passed through a bandpass filter for extracting and extracting only the components, and the vertical bounce speed dZv (wheel speed reference vehicle body vibration) that is a vibration component near the vehicle body resonance frequency of the vertical bounce speed aZv is obtained.
Thus, the reason why only the component near the vehicle body resonance frequency is extracted from the vertical bounce speed aZv of the vehicle body 3 by filtering and is extracted is that the wheel speed reference vertical bounce speed aZv is a wheel speed fluctuation or noise component due to acceleration / deceleration of the entire vehicle. This is because it is necessary to exclude these from the vertical bounce speed aZv and to obtain a wheel speed reference vertical bounce speed dZv that represents only vehicle body vibration.

Further, in the band-pass filter processing unit 56 in FIG. 10 (step S64 in FIG. 11), a component near the vehicle body resonance frequency from the pitch angular velocity aθp of the vehicle body 3 obtained by the pitching behavior calculation unit 54 in FIG. 10 (step S63 in FIG. 11). This pitch angular velocity aθp is passed through a bandpass filter for extracting and extracting only the pitch angular velocity dθp (wheel speed reference vehicle body vibration), which is a vibration component near the vehicle body resonance frequency of the pitch angular velocity aθp.
The reason for extracting and extracting only the component near the vehicle body resonance frequency by filtering from the pitch angular velocity aθp of the vehicle body 3 as described above is that the pitch angular velocity aθp includes wheel speed fluctuation and noise components due to acceleration and deceleration of the entire vehicle, This is because it is necessary to exclude these from the pitch angular velocity aθp to be the wheel speed reference pitch angular velocity dθp that represents only the vehicle body vibration.

While the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is estimated as described above, the braking / driving force reference vehicle body vibration estimator 25b shown in FIG. 10 performs step S65 in FIG. The required torque dTm obtained by the calculation unit 21 is read as the braking / driving torque of the vehicle.

The braking / driving force reference vehicle body vibration estimator 25b is similar to that shown in FIG. 3 and includes a vehicle model 37. In step S66 of FIG. 11, the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) described above is used. Is used as an observer input, and the vehicle model 37 is used to estimate the state from the required torque dTm (vehicle braking / driving torque), so that the vehicle body vibration (vertical bounce amount fZv, vertical bounce speed dfZv, pitch) The angle fθp and the pitch angular velocity dfθp) are calculated and estimated.
However, the estimation accuracy is low due to modeling errors, disturbances (road surface unevenness), and the like.

Therefore, in this embodiment as well, as in the first embodiment, the vehicle model is calculated from the required torque dTm (vehicle braking / driving torque) in the braking / driving force reference vehicle body vibration estimator 25b (step S66 in FIG. 4) in FIG. When estimating and estimating the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) by estimating the state with an observer using 37,
As shown in FIG. 10, the vehicle model 37 is used from the required torque dTm (braking / driving torque of the vehicle) while the wheel speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) from the calculation units 55 and 56 is also input as an observer. Thus, the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) is calculated.

Thus, the braking / driving force reference vehicle body vibration estimator 25b in FIG. 10 uses the vehicle speed model body vibration (vertical bounce speed dZv and pitch angular speed dθp) as an observer input, and the vehicle model from the required torque dTm (vehicle braking / driving torque). By calculating the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) based on 37,
The disturbance robustness and stability of the braking / driving force reference vehicle body vibration estimator 25b (vehicle model 37) can be made compatible.
Further, since the braking / driving force reference vehicle body vibration x is estimated from the required torque dTm (vehicle braking / driving torque) that is the cause of the vehicle body vibration, the braking / driving force reference vehicle body vibration is generated not before the vehicle body vibration is generated but before the vehicle body vibration is generated. x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp) can be estimated in a feed-forward manner as the final vehicle body vibration.

In step S67 of FIG. 11, the braking / driving torque correction amount calculation unit 26 of FIG. 10 performs braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, the braking and driving torque correction amount ΔTm required to inhibit the pitch angular velocity Dfshitapi) is calculated as follows.
That is, the regulator gain Kr shown in FIG. 10 with reference numeral 38 (for the first embodiment and the first embodiment) for the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, pitch angular speed dfθp). Similarly, setting is given and multiplied, and the resulting linear sum of the multiplication values is set as the braking / driving torque correction amount ΔTm .

The braking / driving torque correction amount ΔTm obtained as described above by the braking / driving torque correction amount calculation unit 26 (step S67 in FIG. 11) in FIG. 10 is supplied to the adder 24 in FIG.
The adder 24, the required torque dTm of the driver by the operation unit 21 was determined to as the corrected only body vibration suppressing braking and driving torque correction amount? Tm, satisfying the requirements of the driver while suppressing the vehicle body vibration Determine the target torque cTm .
The motor torque command value calculation unit 23 in FIG. 2 limits the above target torque cTm so as to meet the torque request from the other system 27, or increases or decreases the final motor torque command value for realizing this. tTm is obtained and contributes to drive control of the motor 4 via the inverter 8.

<Effect of the second embodiment>
Thus, also in the vehicle system vibration control of this embodiment, the motor 4 reduces the vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) while reducing the driver's required torque dTm . The drive will be controlled to satisfy,
Control of vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) can improve riding comfort as well as control the vehicle body posture when turning the vehicle. Stability can also be improved.

Moreover, according to the present embodiment, when estimating the vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) for the above-described vehicle system vibration control,
The planned correlation illustrated in Figs. 6 and 7 between the longitudinal displacements Xtf, Xtr and the vertical displacements Zf, Zr of the front wheels 1FL, 1FR and rear wheels 1RL, 1RR with respect to the vehicle body 3 (suspension geometry characteristics) From the average front wheel speed VwF and the average rear wheel speed VwR, the wheel speed reference vehicle body vibration (vertical bounce speed aZv and pitch angular speed aθp) is estimated,
From the estimation results aZv, aθp, only the components near the vehicle body resonance frequency are extracted in the bandpass filter processing units 55, 56 (step S64), and the wheel speed reference vehicle body vibration (vertical bounce velocity dZv and pitch angular velocity dθp) is estimated.
This wheel speed reference body vibration (vertical bounce speed dZv and pitch angular speed dθp) is used as an observer input, and braking / driving force reference body vibration x (vertical bounce) using the vehicle model 37 from the required drive torque dTm (vehicle braking / driving force). The amount fZv, the vertical bounce speed dfZv, the pitch angle fθp, and the pitch angular speed dfθp) are obtained to obtain the final vehicle body vibration, so that the following effects can be obtained.

That is, it is possible to estimate the final vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) without adding a suspension stroke sensor as in the prior art. Is advantageous.
In addition, without using torque or force that changes according to deterioration over time or increase / decrease in the number of passengers, such as spring constant and vehicle mass, wheels can be obtained from average front wheel speed VwF and average rear wheel speed VwR, that is, from wheel speed information. Since the speed reference vehicle body vibration (vertical bounce speed dZv and pitch angular speed dθp) is estimated, the estimation accuracy can be improved.

Furthermore, using this vehicle model 37 from the required drive torque dTm (vehicle braking / driving force) while using this highly accurate wheel speed reference vehicle body vibration (vertical bounce velocity dZv and pitch angular velocity dθp) as an observer input, In order to estimate the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) that is vibration,
This braking / driving force reference vehicle body vibration (final vehicle body vibration) x can be made highly accurate with excellent disturbance robustness, and the effect of the vibration suppression control can be made remarkable.

In addition, the vehicle model 37 is determined from the braking / driving force dTm of the vehicle before the vehicle body vibration is generated without using the wheel speed reference vehicle body vibration (vertical bounce velocity dZv and pitch angular velocity dθp) as the final vehicle body vibration. The braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp) estimated by using the vehicle body vibration, even when the vehicle system vibration control is feedforward control. Further, there is no problem that the estimation of the vehicle body vibration is delayed and the vehicle system vibration control cannot be performed as intended.

<Other examples>
In the illustrated embodiment described above, the case where the vehicle body vibration estimation device is used for vehicle system vibration control via the braking / driving force operation of an electric vehicle using only the motor 4 as a power source has been described.
It can be used in the same way for a vehicle system vibration control device through engine control of a vehicle mounted with an engine vehicle such as an internal combustion engine as a power source. The same can be applied to a vehicle system vibration control device through operation.

In addition, the wheel speed information used for estimating the body vibration is not limited to the average front wheel speed VwF and the average rear wheel speed VwR as shown in the figure, but based on the four-wheel model using the wheel speeds VwFL, VwER, VwRL, and VwRR individually. Car body vibration can also be estimated.
In this case, the wheel speed reference vehicle body vibration that is an observer input to the vehicle model 37 is not limited to the pitch angular velocity dθp and the vertical bounce velocity dZv in the illustrated example. Can be estimated.

  In the first embodiment, when the frequency component representing the vehicle body vibration (the longitudinal movement component of the wheel with respect to the vehicle body 3) is extracted from the average front wheel speed VwF and the average rear wheel speed VwR, the vehicle body is derived from the average front wheel speed VwF and the average rear wheel speed VwR. Using a bandpass filter that extracts only the components near the resonance frequency, the vehicle body resonance frequency vicinity vibration component fVwF of the average front wheel speed VwF and the vehicle body resonance frequency vicinity vibration component fVwR of the average rear wheel speed VwR are obtained, and these are obtained as wheel speeds. Although it has contributed to the estimation of the reference vehicle body vibration (pitch angular velocity dθp and vertical bounce velocity dZv), the following wheel speed information may be used instead.

In other words, a means for accurately detecting or estimating the vehicle speed, which is the ground speed of the vehicle body 3, is provided, and the deviations of the vehicle body velocity from the average front wheel speed VwF and the average rear wheel speed VwR are respectively determined by the vehicle body resonance of the average front wheel speed VwF. Instead of the near-frequency vibration component fVwF and the vehicle body resonance frequency vicinity vibration component fVwR of the average rear wheel speed VwR, it may be used to estimate the wheel speed reference vehicle body vibration (pitch angular velocity dθp and vertical bounce velocity dZv).
However, this method is disadvantageous in terms of estimation accuracy of vehicle body vibration considering the slip ratio difference between the driving wheel and the driven wheel, and the average front wheel speed VwF obtained using the bandpass filter as in the first embodiment. It is more practical to use the vehicle body resonance frequency vicinity vibration component fVwF and the vehicle body resonance frequency vicinity vibration component fVwR of the average rear wheel speed VwR.

Further, in the second embodiment, only the component near the vehicle body resonance frequency is extracted from the vertical bounce speed aZv and the pitch angular velocity aθp of the vehicle body 3 directly obtained from the average front wheel speed VwF and the average rear wheel speed VwR by bandpass filter processing. Wheel speed reference vehicle body vibration (pitch angular velocity dθp and vertical bounce velocity dZv) representing only vibration,
Instead, the vertical speed bounce speed aZv and pitch angular speed aθp are filtered to remove drift components, or filtered to remove low frequency components below the frequency component near the vehicle body resonance frequency, Reference vehicle body vibration (pitch angular velocity dθp and vertical bounce velocity dZv) may be obtained.

In each of the illustrated examples, as the braking / driving force used for estimating the braking / driving force reference vehicle body vibration x (vertical bounce amount fZv, vertical bounce speed dfZv, pitch angle fθp, and pitch angular speed dfθp), the calculation unit 21 in FIG. Although the obtained required torque dTm is used, the present invention is not limited to this, and any desired amount can be used as long as it represents a braking / driving force of the vehicle.
Further, when the vehicle has an actuator that automatically adjusts the braking / driving force, it is necessary to calculate the required torque of the vehicle from the operation of the actuator and use the required torque as the braking / driving force of the vehicle. Needless to say.

1FL, 1FR Left and right front wheels
1RL, 1RR Left and right rear wheels
2 Steering wheel
3 Body (Spring mass)
4 Motor
5 Transmission
6 Motor controller
7 Battery (capacitor)
8 Inverter
11FL, 11FR, 11RL, 11RR Wheel speed sensor (wheel speed physical quantity detection means)
13 Accelerator position sensor
14 Brake pedal force sensor
20 Vehicle speed calculator
21 Required torque calculator (braking / driving force detection means)
22 Vehicle system vibration control calculation section
23 Motor torque command value calculator
24 Adder (braking / driving force correction means)
25 Body vibration estimation unit
25a Wheel speed reference body vibration estimator (Wheel speed reference body vibration estimation means)
25b Braking / driving force based vehicle body vibration estimator (braking / driving force based vehicle body vibration estimating means)
26 Braking / driving torque correction amount calculation unit (braking / driving force correction amount calculation means)
31 Average front wheel speed calculator
32 Average rear wheel speed calculator
33 Bandpass filter processing unit for front wheels
34 Rear wheel bandpass filter processing section
35 Bounce behavior calculation unit (front wheel vertical motion estimation unit, rear wheel vertical motion estimation unit)
36 Pitching behavior calculation unit (front wheel vertical motion estimation unit, rear wheel vertical motion estimation unit)
37 Vehicle model
38 Regulator gain
51 Average front wheel speed calculator
52 Average rear wheel speed calculator
53 Bounce behavior calculation unit (front wheel vertical motion estimation unit, rear wheel vertical motion estimation unit)
54 Pitching behavior calculation unit (front wheel vertical motion estimation unit, rear wheel vertical motion estimation unit)
55,56 Bandpass filter processing section

Claims (21)

In the device for estimating the vibration of the vehicle body, which is the sprung mass of a vehicle that has the front wheel suspended through the front wheel suspension device and the rear wheel suspended through the rear wheel suspension device,
Front wheel speed physical quantity related to the front wheel speed is a circumferential velocity of the front wheel, and the wheel speed physical quantity detecting means for detecting a wheel speed physical quantity after related to wheel speed after a and the peripheral speed of the rear wheel,
Using the front wheel speed physical quantity and the rear wheel speed physical quantity detected by the means, the correlation between the front wheel longitudinal displacement amount and the vertical displacement amount with respect to the vehicle body determined by the front wheel speed physical amount and the geometric characteristics of the front wheel suspension device. as well as the rear wheel speed physical quantity, and depends on the geometry characteristics of the rear wheel suspension device, the correlation between the longitudinal direction displacement of the rear wheels relative to the vehicle body in the vertical direction displacement amount, the vehicle wheel speed physical quantity reference vehicle body Wheel speed physical quantity reference vehicle body vibration estimation means for estimating vibration,
Braking / driving force detecting means for detecting braking / driving force of the vehicle;
The vehicle body vibration estimated by the wheel speed physical quantity reference vehicle body vibration estimating means is used as an observer input, and the vehicle body vibration is estimated from the vehicle braking / driving force obtained by the braking / driving force detecting means by using a vehicle model. A vehicle body vibration estimation apparatus comprising: a braking / driving force reference vehicle body vibration estimation means for generating a vehicle body vibration. In the vehicle body vibration estimation device according to claim 1 ,
The correlation between the longitudinal displacement amount and the vertical displacement amount of the front wheel and the rear wheel with respect to the vehicle body is a geometrical constraint condition determined according to the link structure of the front wheel suspension device and the rear wheel suspension device , respectively . A vehicle body vibration estimation device characterized by being previously mapped. In the vehicle body vibration estimation device according to claim 1 ,
The correlation between the longitudinal displacement amount and the vertical displacement amount of the front wheel and the rear wheel with respect to the vehicle body is a geometrical constraint condition determined according to the link structure of the front wheel suspension device and the rear wheel suspension device , respectively . A vehicle body vibration estimation apparatus characterized by being modeled in advance. In the vehicle body vibration estimation device according to claim 1 ,
The correlation between the longitudinal displacement amount and the vertical displacement amount of the front and rear wheels with respect to the vehicle body is linearly approximated to a geometric constraint condition determined according to the link structure of the front wheel suspension device and the rear wheel suspension device , respectively . A vehicle body vibration estimating apparatus characterized by having a proportional coefficient. In the vehicle body vibration estimation device according to any one of claims 1 to 4 ,
The vehicle body vibration estimation apparatus characterized in that the vehicle body vibration estimated by the wheel speed physical quantity reference vehicle body vibration estimation means is pitching vibration and / or vertical vibration. In the vehicle body vibration estimation device according to any one of claims 1 to 5 ,
The wheel speed physical quantity reference vehicle body vibration estimation means calculates a front wheel front-rear direction displacement amount from the front wheel speed physical amount, and the front wheel front-rear direction displacement amount, and the front wheel front-rear direction displacement amount and the vertical direction displacement amount with respect to the vehicle body. From the correlation between the front wheel vertical motion estimation unit for estimating the vertical displacement of the front wheel,
A rear wheel longitudinal displacement is calculated from the rear wheel speed physical quantity, and the correlation between the rear wheel longitudinal displacement and the rear wheel longitudinal displacement and vertical displacement relative to the vehicle body is calculated. A rear wheel vertical motion estimation unit for estimating the vertical displacement of the rear wheel,
A vehicle body vibration estimation apparatus for estimating the vehicle body speed reference vehicle body vibration based on the estimated vertical displacement amount of the front wheel and the vertical displacement amount of the rear wheel. In the vehicle body vibration estimation device according to any one of claims 1 to 5 ,
The wheel speed physical quantity reference vehicle body vibration estimation means calculates a first motion equation for calculating a vertical displacement amount of a front wheel from the front wheel speed physical quantity, and a second equation for calculating a vertical displacement quantity of a rear wheel from the rear wheel speed physical quantity. The third equation of motion that calculates the pitching motion of the vehicle body from the equation of motion of the front wheel, the vertical displacement amount of the front wheel and the vertical displacement amount of the rear wheel, and the vehicle body from the vertical displacement amount of the front wheel and the vertical displacement amount of the rear wheel It is characterized by estimating the vehicle body vibration based on the wheel speed physical quantity of the vehicle body by solving the simultaneous equations with the fourth equation of motion for calculating the vertical motion of the vehicle to obtain the pitching motion and the vertical motion of the vehicle body Car body vibration estimation device. In the vehicle body vibration estimation device according to any one of claims 1 to 7 ,
The wheel speed physical quantity reference vehicle body vibration estimation means contributes to the estimation of the wheel speed physical quantity reference vehicle body vibration using the wheel speed physical quantity vibration component accompanying the longitudinal vibration of the vehicle body among the wheel speed physical quantity. Car body vibration estimation device. In the vehicle body vibration estimation device according to claim 8 ,
The wheel speed physical quantity reference vehicle body vibration estimation means contributes to the estimation of the wheel speed physical quantity reference vehicle body vibration using the deviation between the wheel speed physical quantity and the vehicle body speed as the wheel speed physical quantity vibration component. Vibration estimation device. In the vehicle body vibration estimation device according to claim 8 ,
The wheel speed physical quantity reference vehicle body vibration estimation means uses the filtered signal obtained by extracting only the component near the vehicle body resonance frequency from the wheel speed physical quantity as the wheel speed physical quantity vibration component, and the wheel speed physical quantity reference vehicle body. A vehicle body vibration estimation apparatus, which contributes to vibration estimation. In the vehicle body vibration estimation device according to any one of claims 1 to 7 ,
The wheel speed physical quantity reference vehicle body vibration estimation means, said relative wheel speed physical quantity reference vehicle body vibration estimated by performing a filtering process to extract only components around the vehicle body resonance frequency, the final wheel speed physical quantity reference vehicle body vibration estimation value A vehicle body vibration estimation apparatus characterized by the above. In the vehicle body vibration estimation device according to any one of claims 1 to 11 ,
The braking / driving force detecting means calculates a required torque of the vehicle from a driving operation, and uses the required torque as a braking / driving force of the vehicle for estimation by the wheel speed physical quantity reference vehicle body vibration estimating means. A vehicle body vibration estimation device. The vehicle body vibration estimation device according to any one of claims 1 to 12 , wherein the vehicle includes an actuator that automatically adjusts braking / driving force.
The braking / driving force detecting means calculates a required torque of the vehicle from the operation of the actuator, and uses the required torque as a braking / driving force of the vehicle for estimation by the wheel speed physical quantity reference vehicle body vibration estimating means. A vehicle body vibration estimation device characterized by the above. In the vehicle body vibration estimation device according to any one of claims 5 to 13 ,
The braking / driving force reference vehicle body vibration estimation means uses the pitching vibration and / or vertical vibration estimated by the wheel speed physical quantity reference vehicle body vibration estimation means as an observer input, and the braking / driving force reference vehicle body vibration which is the final vehicle body vibration. A vehicle body vibration estimation apparatus for estimating pitching vibration and / or vertical vibration. The vehicle body vibration estimation device according to any one of claims 1 to 14 ,
Braking / driving force correction amount calculating means for calculating a braking / driving force correction amount necessary for reducing the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimating means;
A vehicle system vibration control device comprising braking / driving force correcting means for correcting the braking / driving force of the vehicle by a braking / driving force correction amount obtained by the means. In the vehicle system vibration control device according to claim 15 ,
The braking / driving force correction amount calculating means obtains the braking / driving force correction amount by multiplying the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimating means by a predetermined gain. Vehicle system vibration control device. In the vehicle system vibration control device according to claim 15 or 16 ,
The braking / driving force correction amount calculating means uses the linear sum of multiplication values obtained by multiplying the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimating means by a predetermined gain as the braking / driving force correction amount. Vehicle system vibration control device characterized by being a thing. In the vehicle system vibration control device according to claim 17 ,
The vehicle system vibration control device according to claim 1, wherein the predetermined gain is a regulator gain determined by weighting a degree of suppression for each type of final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimation unit. In the vehicle system vibration control device according to claim 17 ,
The predetermined gain is composed of a plurality of regulator gains set by changing a weighting pattern of a degree of suppression with respect to the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimation unit,
The braking / driving force correction amount calculating means uses the sum of integrated values of the plurality of regulator gains and the final vehicle body vibration as the braking / driving force correction amount. . In the vehicle system vibration control device according to claim 17 ,
The predetermined gain is composed of a plurality of regulator gains set by changing a weighting pattern of a degree of suppression with respect to the final vehicle body vibration estimated by the braking / driving force reference vehicle body vibration estimation unit,
The braking / driving force correction amount calculating means uses the sum of integrated values of the plurality of regulator gains, tuning gains for these regulator gains, and the final vehicle body vibration as the braking / driving force correction amount. A vehicle system vibration control device characterized by In the vehicle system vibration control device according to any one of claims 15 to 20 ,
The final body vibration body vibration damping control device according to claim pitching vibrations and / or vertical vibrations der Turkey.

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