JP3115052B2 - Body state detection method and apparatus - Google Patents

Abstract

PURPOSE:To simplify detection of the ground touching load of a wheel, pitching, and deceleration of a car body. CONSTITUTION:For example, displacement amounts of compression and expansion of each suspension are detected by front and rear displacement amount detecting parts 12 and 14 disposed to the front and rear suspension portions of a motorcycle, and the displacement amounts are outputted to a control unit 16. A wheel angular velocity is detected through wheel speed sensors 18 and 19 arranged in the vicinity of a wheel and outputted to the control unit 16. The control unit 16 computes a ground touching load, pitching, and deceleration of a car body from a displacement amount and the angular velocity of a wheel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for detecting a vehicle body condition such as a wheel contact load, pitching and vehicle body speed change, and more particularly, for example, a displacement of a front wheel and a rear wheel suspension of a motorcycle. The present invention relates to a vehicle body state detection method and apparatus for detecting a ground contact load of a wheel, a pitching state of a vehicle body, a vehicle body speed change, and the like.

[0002]

2. Description of the Related Art For example, in order to determine a ground contact load of a wheel in an automobile, a method of directly detecting a suspension by attaching a load measuring device (for example, a load cell) to a suspension is used. Further, in order to detect the pitching state of the vehicle body, it is conceivable to attach an angular velocity sensor or a biaxial acceleration sensor near the center of pitching of the vehicle body. further,
In order to detect a vehicle body speed change, a method of measuring by directly attaching an acceleration sensor to a vehicle body has been used.

[0003]

Here, in order to directly determine the wheel contact load by a load measuring device, for example, in the case of a motorcycle, the load measuring device is attached to a lower mounting portion of a coil spring constituting a suspension. Need to be installed. In this case, since an excessive external force is frequently applied to the load measuring device, considerable durability or reliability is required. In addition, a load measuring device that satisfies the above requirements is inevitably a heavy object, and in order to cover the load measuring device, it is necessary to improve the strength of a coil spring, and therefore,
An increase in costs is expected.

If an angular velocity sensor or an acceleration sensor is additionally provided to detect pitching of the vehicle body and vehicle speed change, the arrangement of other components of the vehicle body is restricted, and as a result, the structure of the vehicle body needs to be changed. In addition, the angular velocity sensor and the acceleration sensor are expensive, so that there is a problem that the cost is increased.

SUMMARY OF THE INVENTION The present invention has been made to overcome the above-mentioned inconveniences, and it is possible to reliably detect a wheel contact load, a pitching state, a vehicle speed change, and the like with an extremely simple structure. An object of the present invention is to provide a method and an apparatus for detecting a vehicle body state that do not require structural changes to the vehicle.

[0006]

[0007]

[0008]

In order to achieve the above object,
For this purpose, the present invention provides a first step of detecting each displacement amount of a support mechanism that supports a front wheel and a rear wheel, a second step of detecting rotation speeds of a front wheel and a rear wheel, and a third process of obtaining the slip rate of each wheel from the speed, the time each slip ratio causes Na considered 0 or substantially 0, based on the respective amount of displacement portions to determine pitching amount of the vehicle body, the ground of the wheels A fourth step of obtaining a load; and a fifth step of obtaining a vehicle speed variation using the pitching amount and the ground contact load of each wheel from the balance of the moment around the pitching center of the vehicle body. And

[0009]

[0010]

Further, the present invention provides a front wheel displacement detecting means for detecting a displacement of a support mechanism for supporting a front wheel,
Rear wheel displacement detecting means for detecting the displacement of the support mechanism supporting the rear wheel, front wheel rotational speed detecting means for detecting the rotational speed of the front wheel, and rear wheel rotational speed detecting for detecting the rotational speed of the rear wheel when means and said slip rate calculating means for obtaining a slip ratio of each wheel from the rotational speed, the cause each slip ratio Na considered 0 or substantially 0, based on the respective amount of displacement, pitching seeking pitching of the vehicle body and amount calculating means, wherein when the slip ratio to Na considered 0 or substantially 0
Can, based on the respective amount of displacement, a load calculating means for determining the ground load of each wheel, characterized in that it comprises a speed change calculation means for obtaining a vehicle body speed of the said pitching amount and the ground contact load.

[0012]

With the method and apparatus for detecting the state of the vehicle body of the present invention, focusing on the fact that the load on the wheels depends on the displacement of the support mechanism and the displacement speed of the displacement, the displacement is detected.
From this, the first load component is calculated, and the second load component is calculated from the differential value of the displacement amount, and these are added to determine the ground contact load of the wheel.

Further, in the present invention, the pitching amount of the vehicle body is obtained by detecting each displacement amount of the support mechanism supporting the front wheels and the rear wheels. Note that the pitching amount is obtained as time-series data, and the differential processing is performed to obtain the pitching angular velocity and the pitching angular acceleration.

Further, according to the present invention, the rotational speeds of the front wheels and the rear wheels are detected, and when the slip ratio of each wheel obtained from the rotational speeds can be regarded as 0 or substantially 0, the rotational speed is determined based on the displacement amounts. , And determine the amount of pitching of the body,
The grounding load of each wheel is obtained, and the speed change of the vehicle body can be obtained from the balance of the moment around the pitching center of the vehicle body using the pitching amount and the grounding load of each wheel.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the method for detecting a vehicle body state according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic side view of a motorcycle B equipped with a vehicle body state detecting device according to the present embodiment, and FIG.
It is a block diagram of the said vehicle body state detection apparatus and the brake apparatus controlled by this.

As shown in FIG. 1, the vehicle body state detecting device 10 includes a front displacement detecting unit 12 attached to a front suspension portion of a front wheel Wf and a rear displacement detecting unit 12 attached to a rear suspension portion of a rear wheel Wr. It is configured to include an amount detection unit 14 and a control unit 16 attached to the lower part of the rear end of the sheet. As the front displacement detector 12 and the rear displacement detector 14, for example, a potentiometer that detects that the suspension has been compressed or expanded by a predetermined amount and that has been displaced from the divided voltage difference is used. The rear displacement detector 14
For example, a potentiometer provided at a pivot portion of a swing arm can be used. Then, detection signals from the front displacement amount detection unit 12 and the rear displacement amount detection unit 14 are introduced into the control unit 16. The control unit 16 detects the wheel angular velocity ω via wheel speed sensors 18 and 19 provided near the front wheel Wf and the rear wheel Wr, and introduces a pulse signal of the wheel angular velocity ω into the control unit 16. The control unit 16 is provided with various arithmetic circuits (not shown), and can perform desired arithmetic operations and determinations.

Next, an outline of the brake control device 26 for the front wheels Wf will be described. The brake control device 26 controls the drive of the DC motor 28 by energizing and deactivating the current to the DC motor 28. Control unit 30
Having. The motor control unit 30 is electrically connected to the control unit 16 and receives a signal derived from the control unit 16. The brake device 24 includes a master cylinder 32 driven by the brake lever 22 provided on the handle 31 and a caliper cylinder 34 for braking the front wheel Wf. The master cylinder 32 and the caliper cylinder 34 are connected via the brake control device 26. Interconnected. The master cylinder 32 adjusts the oil pressure under the action of the brake lever 22 and transmits the oil pressure to a cut valve 56 described later. On the other hand, the caliper cylinder 34 operates based on the oil pressure controlled by the cut valve 56. This is for applying a braking force to the disk plate 33.

More specifically, the brake control device 26
As shown in FIG. 2, a DC motor 28 as a drive source is provided. A pinion 36 is connected to a drive shaft of the DC motor 28, and a gear 38 is provided so as to mesh with the pinion 36. At the center of the gear 38, a crankshaft 40 is fixed.
One end of the crank pin 44 is connected via the second pin 2. A crank arm 46 is connected to the other end of the crank pin 44, and a potentiometer 48 for detecting a deviation angle of the crank pin 44 is connected. A cam bearing 50 is rotatably mounted on the outer periphery of the crank pin 44. The cam bearing 50 is a return spring 5
2 is pressed upward. An expander piston 54 that is displaced in the vertical direction under the deflection action of the cam bearing 50 abuts on the upper surface of the cam bearing 50, and a cut valve 56 is actuated by the action of the expander piston 54 in the vertical movement. Open and close the valve. The cut valve 56 is disposed in the cut valve storage section 58 so as to be vertically displaceable. An input port 60 communicating with the master cylinder 32 is provided on the upper surface of the cut valve 56, and an output port communicating with the caliper cylinder 34 is provided at a portion where the cut valve housing 58 and the expander piston 54 are connected. A port 62 is provided. The input port 60 and the output port 62 communicate with each other via a communication hole 64 defined on the outer peripheral surface of the cut valve 56.

On the other hand, the brake control device 27 for the rear wheel Wr
Has the same configuration as the brake control device 26, and communicates a master cylinder 37 connected to the brake pedal 29 of the rear wheel Wr and a caliper cylinder 35 connected to a disk plate 39 of the rear wheel Wr.

The vehicle body state detecting device 10 of this embodiment and the brake device controlled by the same are configured as described above, and the operation thereof will be described next.

First, the case where the wheel contact load is detected using the present apparatus 10 will be described. The various calculations described below are performed in the control unit 16 by introducing signals output from the front displacement detection unit 12, the rear displacement detection unit 14, and the wheel speed sensors 18 and 19 to the control unit 16. .

Generally, the following relational expression (1) is established between the amount of displacement S of the suspension and the ground contact load F of the wheels. That is, F = f (S) + g (ΔS / Δt) (1) where f (S) is the load component of the spring in the vertical direction at the wheel contact point, and g (ΔS / Δt) is the wheel spring component at the wheel contact point. The load component due to the damping characteristics in the vertical direction is shown. Note that ΔS / Δt is a temporal change amount of the displacement amount of the suspension.

Here, the functions f (S) and g (ΔS / Δt)
Are specific to the vehicle and can be measured in advance. One example is shown in FIGS. The displacement amount S of the suspension is determined by the displacement amount detection unit 1 shown in FIG.
It can be obtained from the function h (V) of the output voltages of 2, 14. That is, the displacement amount S of the compression or extension of the front and rear suspensions is detected as the output voltage V from the front and rear displacement amount detection units 12 and 14, and the displacement amount S in the front and rear wheels can be obtained from the output voltage V. . Subsequently, based on the displacement S, the load component f (S) of the spring in the vertical direction of the wheel is determined from the relationship between the load and the displacement S shown in FIG. 3, and similarly, the characteristic shown in FIG. From the curve, load component g (ΔS / Δt) in the vertical direction of the wheel
Is determined, and the wheel ground contact load is obtained by obtaining the sum of the two.

Next, a case where the pitching state of the vehicle body is detected using the present apparatus 10 will be described.

By the way, the pitching angle θP of the wheel base L in the vehicle body can be obtained from the following equation (2). That is, θP ≒ arctan ((ΔSf + ΔSr) / L) (2) where ΔSf indicates the amount of compression displacement of the front wheel Wf in the front suspension, and ΔSr indicates the amount of extension displacement of the rear wheel Wr in the rear suspension (see FIG. 6). ). The compression displacement ΔSf and the extension displacement ΔSr can be obtained from the output voltages detected by the front displacement detector 12 and the rear displacement detector 14, as described above. The wheel base L is determined from each vehicle body. The broken line in FIG. 6 shows a state where the front and rear suspensions are displaced when the front wheel Wf is braked.

The pitching angle θP obtained as described above is converted into time-series data by the control unit 16.
The pitching angular velocity ωP and the pitching angular acceleration αP can be obtained by substituting into the following equations (3) and (4).

ΩP = (θP ₁ −θP ₀ ) / T (3) αP = (ωP ₁ −ωP ₀ ) / T (4) In the equations (3) and (4), P ₀ is the first shows the data, P ₁ represents the next data, T is next to P ₀ P
Indicates the time to get ₁ .

Next, a case where the vehicle body deceleration G is detected by using the present apparatus 10 will be described.

First, the contact loads Ff and Fr of the front and rear wheels when the deceleration G of the vehicle body is almost 0 are detected. This is because the vertical spring load component f (S) at the wheel contact point and the vertical load component g (ΔS /
Δt). that time,
The fact that the vehicle body deceleration G is substantially 0 means that the slip rates λf and λr of the front and rear wheels are λf ≒ based on the wheel angular velocities output from the wheel speed sensors 18 and 19 provided near the wheels.
It can be detected as when λr ≒ 0 is satisfied.

Subsequently, as shown in FIG. 7, the center point P of pitching is determined from the state where the front and rear suspensions are compressed, expanded and displaced. That is, the reference points Af and Af are respectively set to the front suspension and the rear suspension.
r is set, and the movement of the reference points Af and Ar due to the compression and expansion of the suspensions of the front and rear wheels due to the braking of the front wheel Wf is detected (the state where the vehicle body is displaced is shown by a broken line). Points Bf, B to which this reference point has moved
r (hereinafter referred to as moving points Bf and Br) are determined from the vehicle body dimensions and the displacement of the suspension. As shown in FIG. 7, the reference points Af and Ar and the moving points Bf and Br are the pitching center points. Focusing on P
Exist on the same circumference. Therefore, the reference point Af and the moving point B
The intersection of the perpendicular bisector to the straight line connecting r and the vertical bisector to the straight line connecting the reference point Ar and the moving point Br is determined. This intersection is the pitching center point P, and the distances L ₁ , L ₂ and the distance h that bisect the distance between the wheel bases L can be determined based on the pitching center point P. In addition, in the state shown by the broken line in FIG. 7, the ground contact loads Ff, F
The amounts of displacement ΔFf and ΔFr with respect to r are obtained.

When the deceleration G occurs in the vehicle body under the above conditions, the following equation (5) is established by the balance of the moment about the center point P of the pitching determined as described above. That is, GW (H−h) = ΔFf · L ₁ + ΔFr · L ₂ (5) Therefore, when the above equation is modified, the following holds: G = (ΔFf · L ₁ + ΔFr · L ₂ ) / W (H−h) (6) Here, W indicates the sprung load obtained by removing the unsprung load from the grounding load of the front and rear wheels, and H indicates the height of the center of gravity on the spring (see FIG. 8).

The wheel contact load thus determined,
When the pitching and the vehicle body deceleration exceed a preset threshold value, for example, when the contact load of the rear wheel Wr decreases, a control signal is derived from the control unit 16 of the device 10 to the brake control device 26, and the braking is performed. Device 2
4 can be controlled.

Here, the operation of the brake control device 26 will be described. The brake control device 26 forms a state in which the cam bearing 50 is held at the top dead center by the elastic force of the return spring 52 and pushes up the expander piston 54 during normal braking (the state of FIG. 2). . As a result, the cut valve 56 is pushed up through the expander piston 54, and the communication between the input port 60 and the output port 62 is established. Therefore, the master cylinder 3 is held by gripping the brake lever 22.
The brake oil pressure generated in the second port 2 is supplied to the input port 60, the communication hole 64, the output port 62,
8 to the caliper cylinder 34. At this time, the brake oil pressure acts on the output port 62 side to push up the expander piston 54, but the cam bearing 5 abutting against the back surface of the expander piston 54
Since 0 is held at the top dead center by the pressing force of the return spring 52, the expander piston 54 is not displaced. Next, as described above, when it is determined that the wheel contact load, the pitching, and the vehicle body deceleration detected by the control unit 16 have exceeded the preset thresholds, the control unit 16 To energize the DC motor 28,
Control to extinguish. When the DC motor 28 is energized,
The rotating shaft (not shown) of the DC motor 28 is driven to rotate, and the pinion 36 connected coaxially is rotated. With the rotation of the pinion 36, a gear 38 meshing with the pinion 36
The crank pin 44 is displaced via the crank shaft 40 and the crank arm 42 fixed to the gear 38. The cam bearing 50
Moves from the top dead center and acts so that the brake oil pressure acting on the expander piston 54 is added to the torque of the DC motor 28. Therefore, when the expander piston 54 descends by a predetermined amount, the cut valve 56 closes the communication hole 64. Blockage,
As a result, the connection between the input port 60 and the output port 62 is cut off. When the expander piston 54 further descends, the volume on the output port 62 side increases, the hydraulic pressure applied to the caliper sinter 34 decreases, and the braking force of the front wheel Wf decreases. The position of the expander piston 54 is detected as a crank angle by the potentiometer 48 and is introduced into the motor control unit 30 to control the DC motor 28.

As a result, it is possible to secure a sufficient contact load on the rear wheel Wr while avoiding a decrease in the contact load on the rear wheel Wr due to braking of the front wheel Wf. Next, the front wheel W
When the braking force f decreases sufficiently, the power supply to the DC motor 28 is stopped, the crankpin 44 returns to the original position by the elastic force of the return spring 52, and the brake hydraulic pressure increases again. As described above, the brake hydraulic pressure is controlled by repeating the energization and de-energization of the DC motor 28, and it is possible to avoid a decrease in the ground load of the rear wheel Wr due to the braking of the front wheel Wf.

Further, by adjusting the pressure increasing rate or the pressure decreasing rate of the brake hydraulic pressure in accordance with the pitching state, it is possible to perform brake control with less pitching.

Further, the slip rate can be calculated more accurately from the vehicle deceleration, and the accuracy of the brake control is further improved.

As described above, the wheel contact load, the pitching, and the vehicle body deceleration detected by the device 10 are as follows.
This can be effectively used as determination data when controlling the brake device 24 via the brake control device 26.

[0039]

According to the vehicle body state detecting method and apparatus according to the present invention, the following effects can be obtained.

That is, the amount of displacement of compression and extension of the suspension is detected by a potentiometer or the like disposed at a predetermined position, and based on the detected amount of displacement, the wheel contact load, pitching, vehicle body deceleration, etc. are detected. can do. In this case, the device itself can detect the state of the vehicle body with a simple configuration, and even if this device is added, there is no need to change the structure of the vehicle body.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a motorcycle equipped with a vehicle body state detection device according to the present invention.

FIG. 2 is a configuration diagram in which a brake control device is combined with the vehicle body state detection device.

FIG. 3 is an explanatory diagram showing a relationship between a displacement amount of a suspension and a load.

FIG. 4 is an explanatory diagram showing a relationship between a displacement speed of a suspension and a load.

FIG. 5 is an explanatory diagram showing a relationship between an output voltage of a displacement amount detecting means and a suspension displacement amount.

FIG. 6 is an explanatory diagram of a vehicle body state detection method.

FIG. 7 is an explanatory diagram of a vehicle body state detection method.

FIG. 8 is an explanatory diagram of a vehicle body state detection method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Body state detection apparatus 12 ... Front displacement amount detection part 14 ... Rear displacement amount detection part 16 ... Control unit 18, 19 ... Wheel speed sensor 24 ... Brake device 26, 27 ... Brake control device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-41215 (JP, A) JP-A-1-247256 (JP, A) JP-A-58-8414 (JP, A) JP-A-59-1984 84611 (JP, A) JP-A-61-113584 (JP, A) JP-A-63-41217 (JP, A) JP-A-49-54790 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) B62K 25/04 B60L 3/00 B60T 8/00

Claims (2)

(57) [Claims] A first step of detecting the amount of displacement of a support mechanism that supports a front wheel and a rear wheel; a second step of detecting rotation speeds of a front wheel and a rear wheel; a third process of obtaining the slip rate of each wheel, wherein, when the slip ratio to Na considered 0 or substantially 0, based on the respective amount of displacement portions to determine pitching amount of the vehicle body, the ground load of each wheel And a fifth step of calculating the vehicle speed using the pitching amount and the ground contact load of each wheel from the balance of the moment around the pitching center of the vehicle body. Body state detection method. 2. A front wheel displacement detecting means for detecting a displacement of a support mechanism supporting a front wheel; a rear wheel displacement detecting means for detecting a displacement of a support mechanism supporting a rear wheel; Front wheel rotation speed detection means for detecting a rotation speed; rear wheel rotation speed detection means for detecting a rotation speed of a rear wheel; slip rate calculation means for determining a slip rate of each wheel from each of the rotation speeds; when the rate to the name considered 0 or substantially 0, based on the respective amount of displacement, and the pitching amount calculating means for calculating a pitching amount of the vehicle body, when said respective slip ratio causes Na considered 0 or substantially 0, the respective displacement A vehicle body state detecting device, comprising: a load calculating unit that calculates a ground contact load of each wheel based on the following formula; and a variable speed calculating unit that calculates a vehicle body variable speed from the pitching amount and the ground contact load.