JP3142642B2 - Vehicle body bank angle calculation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a motorcycle,
The present invention relates to a vehicle body bank angle calculation device capable of accurately calculating a vehicle body inclination angle (hereinafter, referred to as a bank angle) in a direction orthogonal to a traveling direction.

[0002]

2. Description of the Related Art For example, in a motorcycle or the like, a so-called brake control device that controls the wheel speed of a vehicle being braked by comparing it with the vehicle speed is used. In this brake control device, the slip rate is obtained from the wheel speed and the vehicle speed, and when the slip ratio becomes equal to or higher than the target slip ratio, the wheel speed is controlled by reducing the brake oil pressure to reduce the slip ratio. To obtain the optimum braking force.

There is also a driving force control device that controls the driving force by adjusting the ignition timing of the engine in response to sudden start or a change in the road surface friction coefficient. Also in this driving force control device, the wheel speed and the vehicle speed are used for control.

When such control is performed by a motorcycle,
By making the bank angle contribute to the control, precise control can be performed. As a method of detecting the bank angle, a method of detecting a distance of a predetermined portion of the vehicle body with respect to the road surface using a sensor (Japanese Utility Model Application Laid-Open No. 63-193362), a method of detecting using a tilt meter, a method of estimating a steering angle A method of calculating a bank angle from a vehicle speed by calculation has been proposed.

[0005]

However, the inclinometer is very expensive, and the method of determining the bank angle by measuring the distance to the road surface using a sensor does not provide the reflection state of the road surface or the road surface. There is a lot of noise due to irregularities and the like, and it is difficult to obtain a highly accurate bank angle.

Further, in the method of calculating the bank angle from the steering angle and the estimated vehicle speed by calculation, the correlation between the steering angle and the bank angle during traveling at high speed is poor, and there is a possibility that reliability may be lacking.

SUMMARY OF THE INVENTION The present invention has been made in order to solve such a problem, and has as its object to provide an apparatus for calculating a bank angle of a vehicle body, which is inexpensive and can accurately obtain a bank angle.

[0008] To achieve the above object, the present invention provides:
Front wheel speed detecting means for detecting front wheel speed, rear wheel speed detecting means for detecting rear wheel speed, speed difference calculating means for obtaining a speed difference between the front wheel speed and the rear wheel speed. A storage unit for storing a relationship between a predetermined wheel speed of the front wheels and a vehicle body inclination angle with respect to the speed difference, and the storage unit based on the detected wheel speeds of the front wheels and the obtained speed difference. The vehicle body inclination angle is obtained by using the following method.

[0009]

In the vehicle bank angle calculating device according to the present invention, the bank angle is obtained based on the wheel speeds of the front and rear wheels and the speed difference. In this case, the wheel speed is calculated based on the turning radius (distance between the center of rotation and the ground contact point) and the rotating speed (number of rotations) in the vertical state. Therefore, even if the vehicle body speed is the same, the actual wheel radius is reduced and the rotation speed (rotational speed) is increased by tilting the vehicle body, so that the calculated wheel speed increases. The bank angle was determined by paying attention to the fact that the difference in the wheel radii of the wheels was different and the speed difference between the front and rear wheels was changed by the change in the inclination angle. Therefore, the bank angle can be calculated with high accuracy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a vehicle body bank angle calculating device according to the present invention will be described below in detail with reference to the accompanying drawings.

In FIG. 2, reference numeral 10 denotes a motorcycle. The motorcycle 10 includes a main body 12, a front wheel (driven wheel) 14, a rear wheel (drive wheel) 16, and a steering wheel 1.
8 is provided. The front wheel portion 14 and the rear wheel portion 16 are respectively provided with a driven wheel rotation speed detection sensor 20 and a drive wheel rotation speed detection sensor 22 each including a rotary encoder and the like.
However, a steering angle detection sensor 26 is provided on the handle portion 18. The sensors 20, 22, 24, and 26 are connected to a control unit 28, and these constitute a vehicle body bank angle calculation device 30 shown in FIG.

The control unit 28 includes a driven wheel rotational speed sensor 20 and a drive wheel rotational speed sensor 2.
2, the wheel speed V of the front wheel section 14 and the rear wheel section 16
wheel speed calculation circuit 32 for calculating wf and Vwr, respectively
An acceleration / deceleration determination circuit 34 for determining the acceleration / deceleration state of the motorcycle 10 based on an output signal of the vehicle acceleration / deceleration detection sensor 24 or another control signal S; a wheel speed signal from a wheel speed calculation circuit 32; An estimated vehicle speed calculation circuit 36 for calculating an estimated vehicle speed Vref based on a vehicle acceleration / deceleration signal from the detection sensor 24 and an acceleration / deceleration determination signal from an acceleration / deceleration determination circuit 34;
f, the wheel speed Vwf of the front wheel portion 14 and the rear wheel portion 16 ,
A slip rate calculating circuit 38 for obtaining slip rates Sf, Sr from Vwr, a brake signal generating circuit 40 for outputting brake signals λB1, λB2 based on the slip rates Sf, Sr, and a front wheel section 14 and a rear wheel section 16 Wheel speeds Vwf, Vwr, estimated vehicle speed Vref, brake signals λB1, λB2, and steering angle detection sensor 2
6 includes a bank angle calculation circuit 42 for calculating a bank angle θB based on the steering angle θh detected at 6, and lookup tables (hereinafter, referred to as LUTs) 44, 46, 48 described later.

In the vehicle body bank angle calculation device 30 configured as described above, the bank angle θ _B is obtained as follows.

In this embodiment, the driven wheel (the front wheel portion 1)
4) and the wheel speeds V _wf and V _wr of the drive wheels (rear wheel portion 16) are obtained, and from these, the estimated vehicle speeds V
Seeking _ref . Here, first, the driven wheel (the front wheel 1
The method of 4) for obtaining the estimated vehicle body speed _Vref from the wheel speed _Vwf will be described with reference to the flowchart of FIG. 3 and FIGS. The estimated vehicle speed calculating circuit 36 calculates the estimated vehicle speed V at every predetermined calculation cycle t as follows.
_{Find ref (n)} . Here, (n) indicates a value in the n-th calculation.

First, while the motorcycle 10 is traveling,
The driven wheel rotation speed detection sensor 20 detects the rotation of the front wheel section 14 (driven wheel) as a pulse signal and outputs the pulse signal to the wheel speed calculation circuit 32. The wheel speed calculation circuit 32 calculates a wheel speed Vwf of the front wheel portion 14 based on the pulse signal.
(N) is obtained and output to the estimated vehicle speed calculation circuit 36 (step S1).

On the other hand, the vehicle acceleration / deceleration detecting sensor 24 disposed on the main body 12 detects the vehicle acceleration / deceleration Gx and outputs the detected acceleration / deceleration Gx to the acceleration / deceleration determining circuit 34 and the estimated vehicle speed calculating circuit 36 (step S2).

The acceleration / deceleration determination circuit 34 determines that the vehicle acceleration / deceleration Gx is equal to or greater than a predetermined value β (β> 0) (| Gx |>
β) is determined (step S3). When the vehicle body acceleration / deceleration Gx is equal to or smaller than a predetermined value β (| Gx | <β), no acceleration / deceleration is performed.
In β), it is determined that acceleration / deceleration is being performed.

When it is determined that there is no acceleration / deceleration, as shown in FIG. 4, the wheel speed Vwf (n) of the front wheel portion 14 is usually determined.
And the actual vehicle speed Vi is small, and the vehicle acceleration / deceleration G obtained from the vehicle acceleration / deceleration detection sensor 24 is small.
This is because it is considered that noise due to vibration of the motorcycle 10 or the like is mixed in x. Therefore, when an acceleration / deceleration determination signal indicating no acceleration / deceleration is supplied from the acceleration / deceleration determination circuit 34, the estimated vehicle speed calculation circuit 36 calculates the estimated vehicle speed Vref based on a preset acceleration / deceleration described below.
Find (n).

That is, if it is determined in step S3 that there is no acceleration / deceleration, the currently input wheel speed Vwf (n) of the front wheel unit 14 is estimated vehicle speed Vref (n-n) obtained by the previous calculation. It is determined whether the value is larger than 1) (step S4). Here, the wheel speed V of the front wheel portion 14
If it is determined that wf (n) is higher than the estimated vehicle speed Vref (n-1), the estimated vehicle speed Vref (n) is obtained as follows (step S5).

V _{ref (n)} = V _{ref (n-1)} + G ₁ × t Here, G ₁ (> 0) is a preset acceleration, and t is a calculation cycle.

If it is determined in step S4 that the wheel speed Vwf (n) of the front wheel portion 14 is lower than the estimated vehicle speed Vref (n-1), the estimated vehicle speed Vref (n-) is further determined. 1) is the wheel speed Vwf of the front wheel section 14
(N) is determined (Step S)
6). If the estimated vehicle speed Vref (n-1) is higher than the wheel speed Vwf (n) of the front wheel section 14, the estimated vehicle speed Vref (n) is obtained as follows (step S).
7).

[0022] _{V ref (n) = V ref} (n-1) -G 2 × t _Here, G 2 (> 0) is deceleration set in advance, t is calculation period.

In step S6, the estimated vehicle speed Vre
If it is determined that f (n-1) is not higher than the wheel speed Vwf (n) of the front wheel section 14 , the estimated vehicle speed Vr
ef (n) is obtained as follows (step S
8).

Vref (n) = Vref (n-1) As described above in steps S4 to S8, the front wheel portion
14 and the estimated vehicle speed Vref
By comparing (n-1) and calculating the estimated vehicle speed Vref (n) based on the result, the estimated vehicle speed Vref (n) can be obtained with high accuracy as shown in FIGS. .

On the other hand, in the motorcycle 10, for example, a slip occurs between the wheels and the road surface at the time of deceleration. Therefore, as shown in FIG. 4, the difference between the wheel speed Vwf of the front wheel portion 14 and the actual vehicle speed Vi is determined. growing. Therefore, the wheel speed Vw of the front wheel portion 14 as shown in steps S4 to S8
If the estimated vehicle speed Vref (n) is calculated based on f (n), it is impossible to obtain a highly accurate estimated vehicle speed Vref close to the actual vehicle speed Vi.

Therefore, when the acceleration / deceleration determining circuit 34 determines that the vehicle acceleration / deceleration Gx is equal to or greater than the predetermined value β, it is determined that the vehicle is accelerating and decelerating, and the estimated vehicle speed V _{ref ( The} method of obtaining _n) is switched (step S9).

V _{ref (n)} = V _{ref (n-1)} + ∫Gxdt Here, t is a calculation cycle.

As described above, by using the value of the vehicle acceleration / deceleration Gx, a highly accurate estimated vehicle speed _{Vref (n)} can be obtained.

The estimated vehicle speed V thus obtained
ref (n), the wheel speed Vw of the front wheel section 14 and the rear wheel section 16
f (n) and Vwr (n) are the slip ratio calculation circuit 38
And the estimated vehicle speed Vref (n) and the front wheel portion
14 and the wheel speeds Vwf (n), Vwr of the rear wheel portion 16
Based on (n), the respective slip ratios Sf (n) and Sr (n) of the front wheel portion 14 and the rear wheel portion 16 are calculated and output to the brake signal generation circuit 40. In the brake signal generation circuit 40, the slip ratios Sf (n) and Sr (n) are 3%
In the above case, it is determined that the brake is operating, and the respective brake signals λB1 (n) and λB2 (n) are set to “1” and output to the bank angle calculation circuit.

The bank angle calculation circuit 42 obtains the bank angle θ _B as follows. The method of calculating the banking angle theta _B will be described with reference to the flowchart of FIG.

First, the estimated vehicle speed Vref (n) obtained as described above, the wheel speeds Vwf (n), Vwr (n) of the front wheel section 14 and the rear wheel section 16 and the brake signal λB
1, λB2 and the steering angle θh detected by the steering angle sensor 26
(N) is read (step S21). Subsequently, the logical sum of the brake signals λB1 (n) and λB2 (n) is 1
Is determined, that is, whether the brake is operating (step S22). If the brake is being operated, the estimated vehicle speed Vref (n) is further reduced to 60 k.
m / h is determined (step S2).
3). If the estimated vehicle speed Vref (n) is 60 km / h or less, the estimated vehicle speed Vref (n) and the steering angle θh
From (n), the bank angle θB is calculated by the LUT 44 shown in FIG.
(N) is obtained (see FIG. 8 (I)). The LUT 44 includes the respective steering angles θ set based on the experimental data.
h, the estimated vehicle speed Vref and the bank angle θ
B is stored, and the bank angle θB (n) is determined based on the stored relationship (see the arrow in FIG. 7) (step S2).
4).

In step S23, the estimated vehicle speed V
_{When ref (n)} is greater than 60 km / h, the bank angle θ _{B (n)} is maintained as the previous bank angle θ _{B (n−1)} (FIG. 8 ₎ .
(See (II)) (Step S25). This is because, when the brake is estimated vehicle velocity V _ref in operation _(n) is greater than 60 km / h is small because the value of the wheel speed difference [Delta] V _W to be described later is in braking operation, the bank angle theta _{B ( This is because n)} cannot be obtained accurately.

If it is determined in step S22 that the brake is not operating (λB1 (n) + λB2 (n) =
0), the estimated vehicle speed Vref (n) is 60
It is determined whether it is greater than km / h (step S2).
6). If the estimated vehicle speed Vref (n) is higher than 60 km / h, then the estimated vehicle speed Vref
It is determined whether or not (n) is equal to or less than 70 km / h (step S27). Estimated vehicle speed Vref (n) is 70k
m / h or less, that is, 60 km / h <Vref (n)
If ≦ 70 km / h, the steering angle θh (n) is 2 °
It is determined whether or not it is below (step S28). When it is determined in step S28 that the steering angle θh (n) is equal to or smaller than 2 °, or in step S26, the estimated vehicle speed Vr
If ef (n) is determined to be 60 km / h or less, it is determined that there is a correlation between the bank angle θB (n) and the steering angle θh (n), and the wheel speed Vwf ( n)
The bank angle θB (n) is obtained from the steering angle θh (n) and the LUT 46 shown in FIG. 9 (see FIGS. 8 (IV) and (III)). The LUT 46 stores the relationship between the wheel speed Vwf (n) of the front wheel unit 14 and the bank angle θB for each steering angle θh set based on the experimental data, and based on this, the bank angle θB (n) is obtained (see the arrow in FIG. 9) (step S29).

The estimated vehicle speed Vref (n) is 70 km /
h or the estimated vehicle speed Vref (n) is 60 km / h or more and less than 70 km / h and the steering angle θh
(N) is greater than 2 ° (steps S27, S2
8), it is determined that there is no correlation between the bank angle θB (n) and the steering angle θh (n), and the wheel speeds Vwf (n) and Vwr (n) of the front wheel unit 14 and the rear wheel unit 16 are determined. Speed difference ΔVw
(N) is obtained (step S30). Then, the front wheel part 1
4 wheel speed Vwf (n) and wheel speed difference ΔVw (n)
From the LUT 48 shown in FIG. 10, the bank angle θB (n)
(See FIGS. 8 (VI) and 8 (V)). The LUT 48 stores the relationship between the wheel speed Vwf (n) of the front wheel unit 14 and the bank angle θB in the case of each wheel speed difference ΔVw (n) set based on the experimental data, and The bank angle θB (n) is obtained based on the
(See arrow 0) (step S31).

After the bank angle θ _{B (n)} is obtained in steps S24, S25, S29, and S31, the calculation of the bank angle θ _{B (n)} is repeated (step S32).

The vehicle body bank angle calculation device 3 according to the present embodiment.
At 0, the estimated vehicle speed Vref is applied without brake braking.
(N) is equal to or greater than 70 km / h, or is greater than 60 km / h and equal to or less than 70 km / h, and the steering angle θh (n) is 2 °.
In the case above (see the hatched portion in FIG. 8), the steering angle θh (n)
Instead of the wheel speed Vwr of the rear wheel 16
Wheel speed difference ΔVw (n) obtained by subtracting the wheel speed Vwf of
Is used. In this case, the wheel speeds Vwf and Vwr of the front wheel portion 14 and the rear wheel portion 16 are determined by the wheel turning radius when the wheels are vertical, that is, the wheel turning speed (rotation speed) and the bank angle 0 ° (from the center of rotation to the ground contact point). Distance). However, when the vehicle body is inclined, the turning radius of the wheel is reduced even if the vehicle speed is constant. Therefore, the actual number of rotations of the wheels increases, and the calculated front wheel portion 14 and the rear wheel portion 14 are increased.
The wheel speeds Vwf and Vwr of the wheel unit 16 increase. Here, since the wheel radii of the front wheel portion 14 and the rear wheel portion 16 are different,
Since the wheel speed difference ΔVw (n) is generated and the wheel speed difference ΔVw (n) changes depending on the bank angle θB (n), the bank angle θB (n) can be obtained with high accuracy. Also, the estimated vehicle speed Vref (n) is 60 km /
h or less, or more than 60 km / h and 70 km /
h and the steering angle θh (n) is 2 ° or less, the steering angle θh (n) and the wheel speed Vwf of the front wheel unit 14
(N), the bank angle θB (n) can be obtained. In addition, the slip ratio S
f, Sr, the wheel speed Vw of the front wheel section 14 due to slip when the brake is operating is determined.
Because f (n) is far away from the actual vehicle speed,
Using the estimated vehicle speed Vref (n) instead of the wheel speed Vwf (n) of the front wheel section 14, the bank angle θB (n) can be accurately obtained from the steering angle θh (n).

The numerical values of the estimated vehicle speed V _ref = 60 km / h and 70 km / h and the steering angle θ _h = 2 ° used as the determination criteria in the present embodiment are values determined by the characteristics of the vehicle body. However, the present invention is not limited to this.

[0038]

According to the vehicle body bank angle calculation device of the present invention, the following effects can be obtained.

That is, since the wheel speed is calculated based on the turning radius (the distance between the center of rotation and the ground contact point) and the rotating speed (the number of revolutions) in the vertical state, the vehicle body tilts even when the vehicle speed is constant. As a result, the calculated wheel speed increases because the rotation radius decreases and the rotation speed increases, and the difference between the front and rear wheel speeds and the wheel The bank angle is obtained based on the speed. Therefore, the bank angle can be calculated with high accuracy.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a vehicle body bank angle calculation device according to the present invention.

FIG. 2 is an explanatory diagram of a motorcycle equipped with the vehicle body bank angle calculation device according to the present invention.

FIG. 3 is a flowchart illustrating a method of calculating an estimated vehicle speed in the vehicle bank angle calculation device according to the present invention.

FIG. 4 is a diagram showing a calculation result of an estimated vehicle speed in the vehicle bank angle calculation device according to the present invention.

FIG. 5 is an explanatory diagram of a calculation method of an estimated vehicle speed in the vehicle bank angle calculation device according to the present invention.

FIG. 6 is a flowchart illustrating a bank angle calculation method of the vehicle body bank angle calculation device according to the present invention.

FIG. 7 is a relationship diagram between an estimated vehicle speed and a bank angle at a certain steering angle in the vehicle bank angle calculation device according to the present invention.

FIG. 8 is a table showing a bank angle calculating method of the vehicle body bank angle calculating device according to the present invention.

FIG. 9 is a diagram showing the relationship between the wheel speed of the driven wheel and the bank angle at a certain steering angle in the vehicle body bank angle calculation device according to the present invention.

FIG. 10 is a diagram showing a relationship between a wheel speed of a driven wheel and a bank angle in a wheel speed difference between a driven wheel and a drive wheel in the vehicle body bank angle calculation device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Motorcycle 20 ... Driven wheel rotation speed detection sensor 22 ... Drive wheel rotation speed detection sensor 24 ... Vehicle acceleration / deceleration detection sensor 26 ... Steering angle detection sensor 30 ... Vehicle bank angle calculation device 32 ... Wheel speed calculation circuit 34 ... Addition Deceleration determination circuit 36 ... Estimated vehicle speed calculation circuit 38 ... Slip ratio calculation circuit 40 ... Brake signal generation circuit 42 ... Bank angle calculation circuit

Continuation of front page (56) References JP-A-60-60512 (JP, A) JP-A-4-121240 (JP, A) JP-A-5-97025 (JP, A) JP-A-6-8816 (JP) , A) JP-A-6-16123 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 17/00-17/10 G01C 9/00-9/10 B60T 8/00 -8/96 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. A front wheel speed detecting means for detecting a front wheel speed, a rear wheel speed detecting means for detecting a rear wheel speed, and a speed difference between the front wheel speed and the rear wheel speed. Speed difference calculating means, storage means for storing a relationship between a predetermined wheel speed of the front wheels and a vehicle body inclination angle with respect to the speed difference, and, based on the detected wheel speeds of the front wheels and the determined speed difference, An apparatus for calculating a bank angle of a vehicle body, wherein the vehicle body inclination angle is obtained using the storage means.