Method and apparatus for preventing forward rollover of a single-track motor vehicle

Abstract

To provide a method for preventing a forward flip-over of a single-track motor vehicle or a flip-over about the vehicle transverse axis of the single-track motor vehicle, during a braking process of its front wheel.SOLUTION: A lift-off indicator parameter is checked, which represents the flip-over hazard by a rear wheel at risk of lifting off or already having lifted off the ground surface, and the braking force at the front wheel is reduced as a function thereof to prevent a flip-over.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] [Background technology]

[0002] Patent Document 1 discloses a method for preventing a forward fall. motorcycle The present invention discloses a method for determining a maximum allowable braking force, the method comprising: - the overall tilt of the vehicle about a horizontal axis relative to the direction of the Earth's gravitational force is determined; The maximum permissible braking value is determined as a function of the determined overall inclination. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] German Patent Application Publication No. 102013217593A1 Summary of the Invention

[0004] The present invention relates to a method for preventing a single-track motor vehicle from tipping forward or from tipping over about its transverse axis during the braking process of its front wheels, - The lift-off index, which indicates the risk of tipping over due to the rear wheel being at risk of lift-off or already lifted off the ground, is determined; This reduces the braking force on the front wheels to prevent tipping over.

[0005] A preferred embodiment of the invention is characterized in that with increasing risk of tipping, a faster and / or stronger braking force reduction occurs at the front wheel.

[0006] A preferred embodiment of the invention is characterized in that the lift-off indicator is determined in dependence on the pitch angle, the pitch angular velocity and the sideslip angle of the rear wheels.

[0007] A preferred embodiment of the present invention comprises: a pitch angle indicator quantity is determined depending on the pitch angle of the motor vehicle; a pitch angular velocity indicator quantity is determined depending on the pitch angular velocity of the motor vehicle; The sideslip angle indicator is determined depending on the sideslip angle of the rear wheels, The lift-off indicator is determined as a function of the pitch angle indicator, the pitch angular velocity indicator, and the sideslip angle indicator; It is characterized by:

[0008] A preferred embodiment of the invention is characterized in that the lift-off indicator is determined by summing the pitch angle indicator, the pitch angular rate indicator, and the sideslip angle indicator.

[0009] A preferred embodiment of the invention is characterized in that the single-track motor vehicle is a motorcycle.

[0010] Furthermore, the invention includes a device comprising means adapted to carry out the method according to the invention, in particular a control device in which program code for carrying out the method according to the invention is stored.

[0011] This device is, for example, an anti-lock system.

[0012] The drawings include FIGS. 1 and 2. [Brief explanation of the drawings]

[0013] [Figure 1] 1 illustrates the determination of a stability index in block diagram form for one embodiment. [Figure 2] 1 shows the procedure of one embodiment of the method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Modern motorcycles often come standard with inertial measurement technology, which serves to detect various riding dynamics data. These riding dynamics data allow the determination of the risk of rear wheel liftoff and, additionally, a stability index that describes the stability of the motorcycle in relation to a lifted rear wheel. Depending on this, the braking force or braking pressure exerted on the front wheel can be reduced. This increases the rear wheel's contact with the road again, which in turn causes the rear wheel to press more firmly onto the road. The lifted rear wheel is then pulled back onto the road again by the pressure reduction at the front wheel.

[0015] Estimation of quantities such as pitch angle, pitch rate or sideslip angle is performed, for example, by the control unit of an anti-lock system. Furthermore, wheel rotation speed can also be taken into account in determining these quantities.

[0016] The stability index is an abstract quantity that reflects the stability of a motorcycle with respect to rear wheel lift during the braking process. During the pressure generation phase, it has a value between 0 and 1, where 0 represents a stable motorcycle and 1 represents an unstable motorcycle. A stable motorcycle in this context means that the rear wheel has good, constant ground contact, whereas a maximally unstable motorcycle has a large lifted rear wheel that is just about to cause the motorcycle to tip over. If the lifted rear wheel is offset significantly to the side and has a large sideslip angle, additional increased instability occurs.

[0017] To form the stability index, at least one of the following quantities is evaluated: - Pitch angle - Pitch Rate - Sideslip angle The pitch angle is the rotation angle of the motorcycle around the horizontal axis. The pitch rate is the time derivative of the pitch angle, or the change in pitch angle per unit time, and can also be called the pitch angular velocity.

[0018] The configuration of an embodiment of the invention is shown in Figure 1. The input quantities are the pitch angle N, the pitch rate dN / dt and the sideslip angle S. In block 101, a quantity I1 representative of the risk of rollover resulting from the pitch angle is determined from the pitch angle N. In block 102, a quantity I2 representative of the risk of rollover resulting from the pitch rate is determined from the pitch rate dN / dt, and in block 103, the risk of rollover resulting from the sideslip angle is determined, represented by an indicator quantity I3, with reference to the sideslip angle S of the rear wheels.

[0019] Blocks 101, 102 and 103 each show an example of a characteristic curve, with the input quantities N, dN / dt and S plotted on the horizontal axis and the corresponding index quantities I1, I2 and I3 plotted on the vertical axis.

[0020] While in FIG. 1 three indicator quantities I1, I2 and I3 are determined, in the simplest case an indicator or criterion can be derived from only one of these input quantities. The characteristic curves listed in blocks 101, 102 and 103 are shown as linear characteristic curves. However, in the simplest case, these characteristic curves can also simply represent, for example, a query as to whether an input quantity exceeds a predefined threshold value. For example, if the pitch angle N exceeds a predefined threshold value N0, I1=1 is set. However, N <N0であれば、I1=0がセットされる。

[0021] Of course, the individual characteristic curves may reflect arbitrarily complex non-linear relationships.

[0022] At block 104, the quantities I1, I2 and I3 are suitably combined and a lift-off indicator quantity I is determined therefrom. In the simplest case, each subcriterion is added, i.e., I = I1 + I2 + I3. Normalization allows us to limit I to a maximum value of 1.

[0023] Of course, more complex combinations of the individual indicators can also be made.

[0024] The procedure of one embodiment of the method is shown in Figure 2. After the method is started in block 200, the output signals of the sensors are evaluated in block 201 and respective indicator values ​​are calculated based thereon. From the individual values, a stability indicator is calculated in block 202. This indicator is evaluated in the next step 203. Depending on the result of the evaluation, different adaptations of the braking force level at the front brakes are carried out in block 204.

[0025] In block 204, if the value of the indicator exceeds, for example, a preset maximum threshold value, this indicates a high probability of the rear wheel being at risk of lifting off or being lifted off. Therefore, a downward adjustment of the brake force is performed. If the indicator indicates a stable vehicle, the brake force level at the front wheels can even be adjusted upward. In this case, the brake force level is always kept below or equal to the driver's setting, i.e., it never exceeds the driver's setting.

[0026] The method starts from the beginning by returning from block 203 to block 201 and ends at block 205 when the driver has stopped braking. [Explanation of symbols]

[0027] Block 201 Block 202 Block 203 Block 204 205 Block I. Floating index amount I1 Pitch angle index I2 Pitch angular velocity index I3 Side slip angle index N pitch angle dN / dt pitch angular velocity S Sideslip angle

Claims

1. 1. A method for preventing a two-wheeled motor vehicle from tipping forward during the braking process of the front wheel, comprising: A lift-off index (I) is determined (202), which indicates the risk of tipping over due to the rear wheel being at risk of lift-off or already lifting off the ground. Relying on this, braking force on the front wheels is reduced (204) to prevent tipping over; With increasing risk of tipping, a more rapid and / or stronger braking force reduction occurs on the front wheels (204), The lift-off indicator (I) is determined depending on the pitch angle (N), the pitch angular velocity (dN / dt), and the side slip angle (S) of the rear wheel that is lifting off or has already lifted off.

2. a pitch angle indicator (I1) is determined depending on the pitch angle (N) of the motor vehicle; a pitch angular velocity index (I2) determined as a function of the pitch angular velocity (dN / dt) of the motor vehicle; A sideslip angle indicator (I3) is determined depending on the sideslip angle (S) of the rear wheels; 2. The method according to claim 1, wherein the lift-off indicator (I) is determined as a function of a pitch angle indicator (I1), a pitch velocity indicator (I2), and a sideslip angle indicator (I3).

3. 3. The method of claim 2, wherein the lift-off indicator (I) is determined by summing a pitch angle indicator (I1), a pitch angular rate indicator (I2), and a sideslip angle indicator (I3).

4. 2. The method of claim 1, wherein the two-wheeled motor vehicle is a motorcycle.

5. 5. A device including means adapted to carry out the method according to claims 1 to 4, characterized in that said device is an anti-lock system.

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