JP3318942B2 - Calculation device for estimated vehicle speed - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for calculating an estimated vehicle speed, etc. of a vehicle required for controlling wheel behavior such as anti-lock. And an apparatus for calculating an estimated vehicle speed of the vehicle body.

[0002]

2. Description of the Related Art In a wheel behavior control device such as an anti-lock system, estimation of a vehicle speed, which is a basis of slip or spin calculation, and estimation of a coefficient of friction between a tire and a road surface are important factors directly affecting control performance. is there. The estimation of the friction coefficient between the tire road surfaces is usually calculated from the estimated value of the vehicle acceleration reached during the control, and the estimated value of the vehicle acceleration is calculated based on the estimated value of the vehicle speed. Therefore, the performance of the wheel behavior control device largely depends on the accuracy of estimating the vehicle speed.

When estimating the vehicle speed only from the wheel speeds, the type of estimation has a great effect on the estimation accuracy. Also, if the vehicle speed is estimated only from the wheel speeds, an excessively slipping or spinning of the wheels will significantly deteriorate the estimation accuracy.

[0004] Therefore, if the estimated vehicle speed and the estimated vehicle acceleration are obtained based on both the information on the acceleration obtained from a reliable accelerometer and the information on the wheel speed, the estimation accuracy can be significantly improved. As the accelerometer, a gravity accelerometer is generally used.

As shown schematically in FIG. 5, the gravity type accelerometer converts the displacement of the vibrator F caused by acceleration into an electric signal using a resistor, a piezo element, a differential transformer, or the like. And a configuration for detecting acceleration.

Accordingly, in a state where excessive slip or spin does not occur on the wheels, an estimated vehicle speed or the like estimated from the wheel speed is used. On the other hand, when excessive slip or spin occurs on the wheels, the output of the gravitational accelerometer is used. It is conceivable to use an estimated vehicle speed or the like estimated based on the vehicle speed.

[0007]

Therefore, in the present invention, when estimating the vehicle speed only from the wheel speeds, the problem is what formula should be used. When the wheel behavior control system is configured, when the occurrence of excessive slip or spin is determined and the convergence is determined, the estimated vehicle speed obtained from the wheel speed and the estimated vehicle speed obtained from the gravitational accelerometer are different. It is necessary that they match each other, and it is desirable that the estimated vehicle body acceleration obtained from the wheel speed and the estimated vehicle body acceleration obtained from the gravitational accelerometer also match.

In order to satisfy these necessary conditions, means for calculating an estimated vehicle body speed estimated from wheel speeds, means for calculating an estimated vehicle body speed estimated based on the corrected output of the gravitational accelerometer, and the former estimated vehicle body speed The problem is how to configure the determination means when switching from the speed to the latter estimated vehicle speed or vice versa.

In order to obtain the estimated vehicle speed at the same time as simple as possible when calculating the estimated vehicle speed, what kind of configuration should be adopted.
In order to increase the degree of dependence on the estimated vehicle speed and acceleration obtained from the gravitational accelerometer according to the degree of the slip or spin excessively, how to configure the structure becomes an issue.

[0010]

In order to solve the above-mentioned problems, an apparatus for calculating an estimated vehicle body speed or the like according to the present invention measures a rotational speed of at least one wheel of a vehicle for each unit operation cycle, Means for outputting a wheel speed, means for outputting a substituted acceleration As based on a gravitational accelerometer, means for calculating and outputting a representative speed Vr based on each wheel speed, and calculation of a reference acceleration Az based on the representative speed Vr Means for outputting the reference acceleration Az based on the representative speed Vr as the final estimated vehicle speed or using the substitution acceleration As based on the gravitational accelerometer as the reference acceleration Az. And means for outputting a switching instruction based on the determination result, and means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction. It is characterized in.

[0011]

If an excessive spin occurs during acceleration, the calculation based on the wheel speed is switched from the calculation based on the wheel speed to the calculation based on the output of the gravitational accelerometer according to the output from the switching instruction output means, and the estimated vehicle speed and the estimated vehicle acceleration are calculated. On the other hand, if excessive spins converge during acceleration, the calculation is switched again to the calculation based on the wheel speed.

If an excessive slip occurs during deceleration,
As described above, the output from the means for outputting the switching instruction switches from the calculation based on the wheel speed to the calculation based on the output of the gravitational accelerometer to calculate the estimated vehicle speed and the estimated vehicle acceleration. Is converged, the calculation is switched again to the calculation based on the wheel speed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Principle Description The wheel speeds of four wheels of a vehicle are V1, V2, V3, V4, the highest speed among them is Vh, the lowest speed is Vl, and the representative speed is V.
r, the estimated vehicle speed is Vv, the estimated vehicle acceleration is Av, the acceleration directly obtained from the gravitational accelerometer is Am (acceleration detected by the G meter), and the corrected acceleration by the gravitational accelerometer is Ac.
(Acceleration detected by the corrected G meter), the substituted acceleration based on Ac to be substituted to obtain the estimated vehicle speed, etc. is As, and the acceleration used for the actual estimation calculation is replaced with the reference acceleration A instead of As.
z, and the speed of the filter is m, n. Note that m and n are 0 ≦ m ≦ 1 and 0 ≦ n ≦ 1, and the unit of each acceleration is the product of the acceleration of gravity and the unit operation cycle. That is, in this specification, all differential operations are expressed as the amount of change between unit operation cycles.

First, it is necessary to find the representative speed Vr.
As an example, a method may be considered in which Vr = Vl in the acceleration process and Vr = Vh in the deceleration process, and when acceleration / deceleration cannot be determined, the previous value is left unchanged. How to determine the acceleration process and the deceleration process will be described later. There are various other methods, but this method is simple and can be widely applied.

Next, it is necessary to obtain the estimated vehicle speed Vv and the estimated vehicle acceleration Av from the representative speed Vr, but it is desirable to associate them with each other and apply an appropriate filter. Therefore, the most straightforward method is dVv = (Vr- Vv ) * m (1) Vv = Vv + dVv (2) Av = Av + (dVv- Av ) * n (3) Here, the variables underlined are the values of the previous cycle. However, this causes a filter delay in Vv, and Vv does not become an unbiased estimate of Vr even at a constant acceleration.

In the wheel behavior control device, the constant acceleration state is a so-called normal state, and in this state, Vv becomes Vr.
It is very bad if the unbiased estimation value is not obtained. As an extremely effective means for solving this, it is conceivable to use dVv = Av + (Vr- ( Vv + Av )) * m (4) instead of the equation (1). This gives V at constant acceleration
v is guaranteed to be an unbiased estimate of Vr.

The acceleration dVr is expressed by the following equation: Vr = Vr + dVr. When the acceleration dVr is constant, that is, when dVr = const, the condition for Vv to be an unbiased estimation value of Vr is as follows: Vv = Vr = If Vr-dVr Av = dVr, then Vv = Vr = Vr + dVr = Vv + dVr Av = Av = dVr. Therefore, when dVr = const, Vr =
In a system where Vv + Av is established equally, Vv becomes an unbiased estimation value of Vr at a constant acceleration. Needless to say, the above equations (4), (2) and (3) satisfy the above conditions, but the equations (1), (2) and (3) do not satisfy such conditions.

Of course, when Vv or Av fluctuates, it is premised on the stability that Vv or Av moves in the direction to cancel them, but in the case of filter calculation, this is automatically guaranteed. Therefore, for example, even if the equation (2) is replaced with Vv = Vv + Av or Vv = Vv + Av, Vv becomes an unbiased estimation value of Vr at a constant acceleration even if there is a difference in the transition period.

Here, if dVv = As (5) is used instead of the equation (4), Vv moves away from the representative speed Vr from the wheel speed and changes according to the substituted acceleration As.

Therefore, when the equations for calculating the estimated vehicle speed Vv and the estimated vehicle acceleration Av are rewritten based on the substituted acceleration, dVv = As (5) Vv = Vv + dVv (2) Av = Av + (dVv- Av ) * n ( 3)

Here, consider the point at which Vv obtained from Vr and Vv obtained from As begin to separate, and the point at which Vv and Vr obtained from As intersect again. When As = Av + (Vr-( Vv + Av )) * m (8) is transformed, (As- Av ) / m = Vr-( Vv + Av ) (9), and As and Av match. At the time, Vr
It can be seen that ( Vv + Av ) matches. Here, Vr is the value of the current cycle, but since Vv and Av are the values of the previous cycle, ( Vv + Av ) is the current predicted value of Vv seen from the previous time. This shows that the current values of Vv and Vv are almost the same.

Therefore, when the equation (8) is satisfied, the equation (4)
Switch to equation (5), and when equation (8) holds again, from equation (5)
By returning to the equation (4), it is possible to smoothly reciprocate between the estimated vehicle speed and acceleration obtained from the wheel speed and the estimated vehicle speed and acceleration obtained from the substituted acceleration based on the gravitational accelerometer.

If equation (8) is an inequality, and the inequality sign is reversed between acceleration for dealing with spin and deceleration for dealing with slip, a switching equation actually used can be obtained. That is, in the acceleration process, As> Ac, As < Av + (Vr- ( Vv + Av )) * m (8a) is switched, and in the deceleration process, As <Ac, and As> Av + (Vr- ( Vv + Av )) * m (8b) may be switched.

The absolute value of the difference between As and Ac, Ax = | As−Ac |
Means the safety factor or the degree of anxiety with respect to the certainty of the correction of the gravity accelerometer. If the correction of the gravitational accelerometer is sufficiently reliable, Ax may be set to 0.

When the slip or spin is extremely large and the reliability of the vehicle speed and acceleration estimated from the wheel speed is completely unreliable (this is represented by a large difference between the left side and the right side of the switching judgment formula), the incompleteness is obtained. However, since it is necessary to rely on the acceleration obtained from the gravitational accelerometer, it is better to set Ax small.

However, if it is determined that the slip or spin will continue for an abnormally long period of time, it is desirable to increase Ax to avoid the danger that Ac will be out of order. As a measure for this, Ax can be increased according to the duration of the slip or spin, that is, the duration of establishment of the switching formula (8b) or (8a).

If the gravitational accelerometer only corrects the zero point and the sensitivity is not corrected, or if the sensitivity is corrected but there is still concern about the sensitivity, Ax is increased according to the increase in the absolute value of Ac. It is desirable to increase.

By the way, the above continuous condition is satisfied.
Not limited to equation (8). Considering the form in which the expression (4) is substituted into the expression (3), Av = Av + ( Av + (Vr- ( Vv + Av )) * m- Av ) * n, which is Av = Av + ( Vr− Vv − Av ) * m * n, and furthermore, Av = Av + ( Av + (Vr− ( Vv + Av )) * n− Av ) * m.

[0029] Therefore, in the above Shoshiki, = Av and rewritten If the result is Av = Av become such a part (a series of term), if Any (8) can be used as an alternative to the right-hand side of the equation. That is, equation (8) shows an example of an equation representing Az, and is expressed as follows. Az = Av + (Vr- ( Vv + Av )) * m (10) Then, the equations (8a) and (8b) can be expressed by the following generalized equations. As <Az (10a) As> Az (10b)

Az is the following equation in addition to the equation shown in (10).
It is also possible to use an expression such as (10 ') or (10 "). Az = Vr- Vv (10') Az = Av + (Vr- ( Vv + Av )) * n (10 ") (10a) when using either (10 ') or (10")
And the relationship of equation (10b) holds.

When equation (10) is adopted, equation (5) is expressed as follows. DVv = As (5) When equation (10 ') is adopted, equation (5) is used. Is transformed to the equation (5 ′) dVv = Av + (As− Av ) * m (5 ′), while when (10 ″) is adopted, the equation (5) becomes
(5 ") Equation dVv = Av + (As- Av ) * m / n (5").

In other words, the above equations (2) and (3) are as follows: Vv = Vv + Av + (Vr- Vv - Av ) * m (2 ') Av = Av + (Vr- Vv- Av ) * m * n (3 '), and the following equation can be obtained from these equations (2'), (3 ') and (10). Az = Av + (Vr- ( Vv + Av )) * m (10) Vv = Vv + Az (11) Av = Av + (Az- Av ) * n (12)

Similarly, the following equations can be obtained from the equations (2 '), (3') and (10 '). Az = Vr- Vv (10 ') Vv = Vv + Av + (Az- Av ) * m (11') Av = Av + (Az- Av ) * m * n (12 ')

Similarly, the following equation can be obtained from the equations (2 '), (3'), and (10 "): Az = Av + (Vr- ( Vv + Av )) * n (10") ) Vv = Vv + Av + (Az- Av ) * m / n (11 ") Av = Av + (Az- Av ) * m (12")

The first combination of (10), (11) and (12), the second combination of (10 '), (11') and (12 ') or (1)
0 "), (11"), and (12 ") are z (0 ≦ z
≤ 1) and can be expressed by generalized equations (13), (14), and (15), where Az = Av + (Vr-( Vv + Av )) * z (13) Vv = Vv + Av + (Az- Av ) * m / z (14) Av = Av + (Az- Av ) * m * n / z (15) In the first combination, z = m, and in the second combination, z = 1. , The third combination corresponds to the case where z = n.

This means that by appropriately setting m, n, and z, the filter speeds of the equations (13), (14), and (15) can be freely set independently of each other.

As described above, the condition for Vv to be an invariant estimated value of Vr when dVr is constant is as follows: If Vv = Vr = Vr-dVr Av = dVr holds, , Vv = Vr = Vr + dVr = Vv + dVr, Av = Av = dVr. Equations 2 ′) and (3 ′) are examples in which this condition is satisfied.

[0038] Similarly, Az comparison substitutable conditions As, if, if satisfied Vv = Vr = Vr-dVr Av = dVr, the next time, that Az = Av = Av = dVr are satisfied It is.

Equations for determining Vv and Av, for example, (2 '),
The expression (3 ′) can be expressed by an expression including Az satisfying the above conditions, and Az can be expressed by an expression including Vr (that is,
Vr used to represent Vv or Av can be represented using Az). Therefore, for example, the expressions (2 ′) and (3 ′) can be combined with Az represented by various expressions such as (10 ′), (10 ′) or (10 ″).

Now, the acceleration process and the deceleration process are determined by the representative speed.
It was necessary for the selection of (Vr) and the selection of the switching types (10a) and (10b).

[0041] This decision is basically, the acceleration process the larger the better of Vl than Vr, is a smaller if deceleration process is more of Vh than Vr, and the deceleration process the recovery process from excessive spin with the exception of treatment Care must be taken not to make a mistake or to mistake the recovery process from an excessive slip as an acceleration process.

As a method for this, it can be considered that the acceleration process is continued while the switching formula (10a) is established, and the deceleration process is continued while the switching formula (10b) is established. Further, the period during which the traction control and the anti-lock control are being performed can be regarded as the acceleration process and the deceleration process, respectively, and the braking operation is performed more widely on the deceleration side (when the brake switch is on). Everything can be considered a deceleration process.

When V1 < Vr <Vh and the judgment of the forcible acceleration process and the deceleration process is not made, Vr is set to Vr = Vr as described above, but the equations (10a) and (10b) are used. Can be considered that the previous acceleration or deceleration determination is continuing, or the expression (10) determination itself can be omitted.

Configuration Next, a description will be given of a configuration in which the device for calculating the estimated vehicle speed or the like according to the present invention is incorporated in an antilock control device.

FIG. 1 is a block diagram of an antilock control device, wherein 1 to 4 are wheel speed sensors for detecting the rotation of four wheels, 5 is a gravitational accelerometer, and 6 is a signal from the wheel speed sensor. A wheel speed calculating device for calculating the wheel speed of each of the four wheels based on the wheel speed; a wheel speed selecting device for selecting a maximum speed, a minimum speed or an average speed from the wheel speeds of the four wheels according to the situation; Correction and other necessary corrections to the output Am of the present invention (see Japanese Patent Application No. Hei.
No. 06743) and a correction device for accelerometer input which outputs acceleration Ac by a gravity type accelerometer after correction.

Further, 9 is an accelerometer safety factor that further corrects the corrected acceleration Ac using the safety factor Ax for the probability of correction of the gravitational accelerometer, and outputs a substituted acceleration As that substitutes for the acceleration Ac. The adding device 10 calculates the reference acceleration Az based on the equation (13), compares Az with As, and uses the Az obtained from the equation (13) as the reference acceleration Az as it is based on the comparison result, or substitutes it. Acceleration As
Is a switching determination device for determining whether or not to use the reference acceleration Az, and 11 is an estimated vehicle acceleration calculation device that calculates and outputs the estimated vehicle acceleration Av by using the selected reference acceleration Az according to equation (15), 12 Is an estimated vehicle speed calculating device that calculates and outputs the estimated vehicle speed Vv by the equation (14) using the selected reference acceleration Az.

Reference numeral 13 refers to the estimated vehicle speed Vv and the estimated vehicle acceleration Av, and determines the sign of wheel lock based on the wheel speed of each wheel from the wheel speed calculator 6,
An anti-lock control judging device for outputting an anti-lock control signal, a solenoid command output for outputting a signal to be sent to a solenoid for controlling a brake oil pressure based on the anti-lock control signal, and a solenoid drive for driving the solenoid, respectively. Actuator.

Next, an apparatus for calculating an estimated vehicle speed according to the present invention will be described with reference to a flowchart shown in FIG.

In step # 1, the accelerometer output Am is read, and in step # 2, the wheel speed of each of the four wheels is calculated based on the outputs from the wheel speed sensors 1-4.

At step # 3, it is determined whether any of the antilock control and the brake operation is being executed, and
If S, it is regarded as a deceleration process, and the process proceeds to step # 8 described later. If NO, it is further determined in step # 4 whether traction control is under control. . Step # 3, #
If all four are NO, the representative speed Vr of the previous cycle is compared with the minimum speed Vl of the four wheels in step # 5, and if Vl is greater than Vr, it is determined that the vehicle is in the acceleration process. Proceed to step # 6.

On the other hand, if Vl is smaller than Vr , the process proceeds to step # 7, where Vr is compared with the maximum speed Vh of the four wheels. If Vh is smaller than Vr, it is determined that the vehicle is in a deceleration process. Judge and proceed to step # 8.

[0052] In the case towards the Vh is greater than Vr, that is, when Vr is in the middle of the Vh and Vl is, Vr is the previous value Vr to follow as it is, it is determined that the acceleration and deceleration are also followed by the last of the process last time Follow the values as they are. Step # 6 outputs an acceleration flag and sets Vl to the current Vr, while step # 8 outputs a deceleration flag and sets Vh to the current Vr.

In step # 9, the output A of the gravitational accelerometer
A zero-point correction and other necessary corrections are added to m to calculate the corrected acceleration Ac by the gravitational accelerometer, and calculate the degree of uncertainty Ax for estimating Ac. In step # 10, the reference acceleration Az calculated from the wheel speed is calculated. In step # 11, it is checked whether the process is an acceleration process or a deceleration process. If the process is an acceleration process, a value obtained by adding Ax to Ac is substituted in step # 12.
In step # 13, As is compared with Az obtained in step # 10, which is a term to be compared. If As is smaller, in step # 16, As is substituted for using As as Az, and the flow advances to step # 17.

In the case of the deceleration process, a value obtained by subtracting Ax from Ac in step # 14 is set as As. If As is larger than Az in step # 15, As is substituted in step # 16. If the result of step # 13 or # 15 using the switching judgment formula is NO, Az uses the value obtained from the wheel speed in step # 10 as it is. When Az to be used is determined, Vv and Av are obtained in step # 17, and a series of calculations is completed.

[0055]

According to the present invention, an apparatus for calculating an estimated vehicle speed or the like according to the present invention includes means for calculating an estimated vehicle speed or the like from wheel speeds, and means for calculating an estimated vehicle speed or the like from a gravity accelerometer. Alternatively, since both means are switched in accordance with the occurrence and convergence of spin, changes in the estimated vehicle speed and the estimated vehicle acceleration can be calculated smoothly.

[0056]

[Brief description of the drawings]

FIG. 1 is a block diagram of an antilock control device provided with a device for calculating an estimated vehicle speed and the like according to the present invention;

FIG. 2 is a flowchart for explaining the operation of the calculation device for calculating an estimated vehicle speed and the like in FIG. 1;

FIG. 3 is a schematic diagram of a gravity accelerometer.

[Explanation of symbols]

 1-4 Wheel speed sensor 5 Gravity accelerometer 8 Accelerometer input correction device 9 Accelerometer safety factor adding device 10 Switching judgment device 11 Estimated vehicle acceleration calculation device 12 Estimated vehicle speed calculation device

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60T 8/00-8/96

Claims (11)

(57) [Claims] 1. A means for measuring a rotation speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction; and determining whether the vehicle is accelerating or decelerating. Based on the result of the determination, the determination means selects a wheel for determining the representative speed, determines that the vehicle body is accelerating, and sets the reference acceleration to Az smaller than the assigned acceleration As. When it is determined that the acceleration is small, or when it is determined that the vehicle body is decelerating and the reference acceleration Az is greater than the substitution acceleration As, the reference acceleration Az based on the representative speed Vr is used as it is as the reference acceleration Az. It is determined that the vehicle body is accelerating and the reference acceleration is A
When it is determined that z is greater than the assigned acceleration As, or when it is determined that the vehicle body is decelerating and the reference acceleration Az
Is determined to be smaller than the substitution acceleration As, the substitution acceleration As is determined to be used as the reference acceleration Az. 2. A means for measuring a rotation speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting an estimated vehicle speed Vv and an estimated vehicle acceleration Av in response to a switching instruction; and determining whether the vehicle is accelerating or decelerating. The determination means selects a wheel for determining a representative speed based on the determination result, and calculates and outputs the representative speed Vr based on each wheel speed. The maximum speed Vh and the minimum speed Vl are calculated, and Vr = Vl for the acceleration process and Vr for the deceleration process.
= Vh, otherwise Vr = Vr is output. 3. A means for measuring a rotational speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining means for determining whether the vehicle body is accelerating or decelerating, based on the result of the determination, selecting wheels for determining a representative speed, and determining the maximum speed Vh and the The minimum speed V1 is compared with the previous representative speed Vr, and if Vr <V1, the acceleration process is performed.
An apparatus for calculating an estimated vehicle speed or the like, characterized in that if Vr > Vh, it is determined that the vehicle is in a deceleration process. 4. A means for measuring a rotational speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining means for determining whether the vehicle is accelerating or decelerating, based on the result of the determination, selecting a wheel for determining a representative speed, and the specific determination is based on wheel behavior control. An apparatus for calculating an estimated vehicle speed or the like, characterized in that it is determined that an acceleration process is continued during traction control control and a deceleration process is continued during antilock control. 5. A means for measuring a rotation speed of at least one wheel of a vehicle for each unit operation cycle and outputting a wheel speed; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining whether the vehicle is accelerating or decelerating, based on the result of the determination, selecting wheels for determining a representative speed, and further performing an acceleration process and a deceleration process of the vehicle body. Means for judging and outputting the corrected acceleration Ac by the gravitational accelerometer and outputting the substituted acceleration As taking into account the certainty of the correction are the substituted acceleration As and the acceleration, which are the degrees of anxiety with respect to the gravitational accelerometer. The absolute value of the difference from Ac is determined. For an acceleration process, As = Ac + Ax, and for a deceleration process, As = Ac−A.
An apparatus for calculating an estimated vehicle speed or the like, characterized in that it outputs x. 6. A means for measuring a rotational speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining whether the vehicle is accelerating or decelerating, based on the result of the determination, selecting wheels for determining a representative speed, and further performing an acceleration process and a deceleration process of the vehicle body. Means for judging and outputting the corrected acceleration Ac by the gravitational accelerometer and outputting the substituted acceleration As taking into account the certainty of the correction are the substituted acceleration As and the acceleration, which are the degrees of anxiety with respect to the gravitational accelerometer. The absolute value of the difference from Ac is determined. For an acceleration process, As = Ac + Ax, and for a deceleration process, As = Ac−A.
x, and outputs an instruction to switch whether to use the estimated speed based on the wheel speed or the estimated speed based on the gravitational accelerometer as the final estimated vehicle speed to calculate the degree of anxiety Ax to the gravitational accelerometer. An apparatus for calculating an estimated vehicle speed or the like, wherein Ax is set to be small when the slip or spin is large and the vehicle speed and acceleration estimated from the vehicle speed are not reliable. 7. A means for measuring a rotation speed of at least one wheel of a vehicle for each unit operation cycle and outputting a wheel speed; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting an estimated vehicle speed Vv and an estimated vehicle acceleration Av in response to a switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining whether the vehicle is accelerating or decelerating, based on the result of the determination, selecting wheels for determining the representative speed, and further performing an acceleration process and a deceleration process of the vehicle. Means for judging and outputting the corrected acceleration Ac by the gravitational accelerometer and outputting the substituted acceleration As taking into account the certainty of the correction are the substituted acceleration As and the acceleration, which are the degrees of anxiety with respect to the gravitational accelerometer. The absolute value of the difference from Ac is determined. For an acceleration process, As = Ac + Ax, and for a deceleration process, As = Ac−A.
x is output, and the means for outputting a switching instruction to use the estimated speed based on the wheel speed or the estimated speed based on the gravitational accelerometer for calculating the degree of anxiety Ax to the gravitational accelerometer is output by the gravitational acceleration An apparatus for calculating an estimated vehicle body speed or the like, wherein Ax is set to be increased in accordance with a continuation time in which an instruction to use an estimated speed based on a total is continued. 8. A unit for measuring a rotation speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle, a unit for calculating and outputting a representative speed Vr based on each wheel speed, Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. Means for calculating and outputting an estimated vehicle speed Vv and an estimated vehicle acceleration Av in response to a switching instruction; and determining whether the vehicle is accelerating or decelerating. Determining whether the vehicle is accelerating or decelerating, based on the result of the determination, selecting wheels for determining a representative speed, and further performing an acceleration process and a deceleration process of the vehicle body. Means for judging and outputting the corrected acceleration Ac by the gravitational accelerometer and outputting the substituted acceleration As taking into account the certainty of the correction are the substituted acceleration As and the acceleration, which are the degrees of anxiety with respect to the gravitational accelerometer. The absolute value of the difference from Ac is determined. For an acceleration process, As = Ac + Ax, and for a deceleration process, As = Ac−A.
x is output, and the calculation of the degree of anxiety Ax to the gravitational accelerometer is set so as to increase Ax when the corrected acceleration Ac by the gravitational accelerometer is large. Etc. calculation device. 9. A unit for measuring a rotation speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle, a unit for calculating and outputting a representative speed Vr based on each wheel speed, Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. And a means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction, wherein the variation dVr of the representative speed Vr is constant. That case, the reference acceleration Az calculating device, such as estimated vehicle speed, characterized in that set to be equal to the variation amount dVr. 10. A means for measuring a rotation speed of at least one wheel of a vehicle for each unit operation cycle and outputting a wheel speed; a means for calculating and outputting a representative speed Vr based on each wheel speed; Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. And means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction, and the variation dVr of the representative speed Vr is constant. In some cases, the estimated vehicle speed Vv is determined to be equal to the representative speed Vr, means for calculating a reference acceleration Az is, if, if Vv = Vr Av = dVr, that satisfy Az = dVr A calculation device for calculating the estimated vehicle body speed and the like. 11. A unit for measuring a rotational speed of at least one wheel of a vehicle and outputting a wheel speed for each unit operation cycle, a unit for calculating and outputting a representative speed Vr based on each wheel speed, Means for outputting the substituted acceleration As calculated based on the accelerometer, means for outputting the reference acceleration Az calculated based on the representative speed Vr, and means for outputting the representative speed Vr for calculating the final estimated vehicle speed. Whether to use the reference acceleration Az based on the reference acceleration Az or to use the substitution acceleration As based on the gravitational accelerometer instead of the reference acceleration Az is determined based on the magnitude relationship between the substitution acceleration As and the reference acceleration Az, and a switching instruction is performed based on the determination result. And means for calculating and outputting the estimated vehicle speed Vv and the estimated vehicle acceleration Av in response to the switching instruction, and the variation dVr of the representative speed Vr is constant. In some cases, the estimated vehicle speed Vv is determined to be equal to the representative speed Vr, means for calculating the estimated vehicle speed Vv and the estimated vehicle acceleration Av, but if, if Vv = Vr Av = dVr, Vv = Vr Av = dVr, and the equations for calculating the reference acceleration Az, the estimated vehicle speed Vv, and the estimated vehicle acceleration Av are: Az = Av + (Vr− ( Vv + Av )) * z (13) Vv = Vv + Av + ( Az − Av ) * m / z (14) Av = Av + (Az− Av ) * m * n / z (15)