Braking device of a vehicle and methods thereof

Abstract

A braking device of a vehicle, comprising: a detector (20) configured to detect driving information, including the actuation state of a brake pedal, vehicle speed and vehicle deceleration, an anti-lock braking system, ABS, (30) which is configured to control a braking force supplied to the wheels (10) of the vehicle by detecting slip generated at the wheels (10), and a control device (40) configured to determine a braking state of the vehicle from the actuation state of the brake pedal, the vehicle speed and the vehicle deceleration detected by the detector (20), and configured to selectively perform ABS control or tilt movement control to reduce a tilt movement of the vehicle according to the braking state of the vehicle, wherein the control device (40) is configured to perform the tilt motion control when the vehicle deceleration detected by the detector (20) is greater than a predetermined deceleration and a tilt coefficient determined by the vehicle speed and a change in the vehicle deceleration is greater than a first predetermined value, wherein the tilt motion control incrementally increases the braking force supplied to the wheels (10) according to the tilt coefficient until the tilt coefficient becomes less than a second predetermined value after the braking force has been supplied to the wheels (10) for a time period, and where the second predetermined value is smaller than the first predetermined value.

Description

Background of the invention; Field of the invention

[0001] The present invention relates to a braking device for a vehicle (e.g., a motor vehicle) and a method thereof. In particular, the present invention relates to a braking device for a vehicle and a method which can reduce a braking distance by minimizing a tilting motion (e.g., pitching motion) that is generated when the vehicle brakes quickly (or abruptly). Description of the related technology

[0002] In general, a hydraulic pressure braking system generates hydraulic brake pressure, generated by pressing a brake pedal, and supplies it to each wheel, thus braking the vehicle. At this point, slippage occurs between the tire and the road surface when a braking force greater than the static frictional force is applied to a tire.

[0003] As is known, a dynamic coefficient of friction is lower than a static coefficient of friction. To provide optimal braking performance, slippage between the tire and the road must be prevented. Furthermore, brake lockup during slippage (e.g., steering lockup during braking due to slippage) must be prevented.

[0004] Thus, an anti-lock braking system (ABS) is used to prevent wheel slippage and locking by controlling the hydraulic brake pressure supplied to each wheel. The ABS comprises multiple solenoid valves that control the hydraulic brake pressure transmitted to each hydraulic brake, an accumulator (e.g., hydraulic accumulator), an electronic control unit (ECU) that controls a hydraulic pressure control device, and electrical / electronic devices such as a hydraulic pressure pump.

[0005] The ABS detects wheel slip generated by applying the brakes on a slippery road or during rapid braking and reduces, maintains (maintains) or increases the hydraulic brake pressure so that the vehicle can achieve optimal lateral grip and stop in the shortest possible distance while maintaining steering stability.

[0006] However, since the center of gravity of a vehicle body is positioned higher compared to a wheel suspension, - as in Fig. Figure 1 shows a tilting motion (in other words, a “tipping” or “nodding”) in which a front section of the vehicle body falls towards the ground when a driver firmly presses down on a brake pedal for rapid braking.

[0007] At this point, when the ABS is activated, a high hydraulic brake pressure is generated at the drive wheels by a hydraulic pressure control device. The braking distance is increased by reducing the hydraulic brake pressure supplied to the drive wheels, thus decreasing the deceleration. Therefore, the problem arises that the braking distance becomes longer.

[0008] The information disclosed in this background section is provided solely for the purpose of better understanding the general background of the invention and should not be regarded as an admission or any indication that this information is part of the prior art as already known to the person skilled in the art.

[0009] From DE 697 34 493 T2, a brake control device for a vehicle is known, comprising a detector configured to detect driving information, including the actuation state of a brake pedal, vehicle speed, and vehicle deceleration; an anti-lock braking system configured to control a braking force applied to the vehicle's wheels by detecting wheel slip; and a control device configured to determine the vehicle's braking state from the actuation state of the brake pedal, vehicle speed, and vehicle deceleration detected by the detector. A corresponding braking method is also known from DE 697 34 493 T2. Explanation of the invention

[0010] The object of the present invention is to provide a braking device and a method which can prevent a braking distance from being increased by a tilting movement generated during rapid braking of a vehicle.

[0011] The problem is solved by a braking device for a vehicle with the features according to claim 1 and by a braking method for a vehicle with the features according to claim 3. Further embodiments of the braking device and the braking method are described in the respective dependent claims.

[0012] This means that the braking device of a vehicle comprises: a detector configured to detect driving information, including the actuation state of a brake pedal, vehicle speed, and vehicle deceleration; an anti-lock braking system (ABS) configured to control a braking force supplied to the wheels of the vehicle by detecting wheel slip; and a control device configured to determine the vehicle's braking state from the actuation state of the brake pedal, vehicle speed, and vehicle deceleration detected by the detector, and configured to selectively perform either ABS control or tilt motion control to reduce any tilting motion of the vehicle, depending on the vehicle's braking state.

[0013] The control device is set up to perform the tilt motion control when the vehicle deceleration detected by the detector is greater than a predetermined deceleration and a tilt coefficient determined by the vehicle speed and a change in vehicle deceleration is greater than a first predetermined value.

[0014] The control device can be set up to stop the tilt movement control when the tilt coefficient is less than a second predetermined value, and can perform ABS control.

[0015] The tilt control gradually increases the braking force supplied to the wheels according to the tilt coefficient, until the tilt coefficient becomes less than a second predetermined value, after the braking force has been supplied to the wheels for a (e.g., predetermined) time period, where the second predetermined value is less than the first predetermined value.

[0016] The inclination coefficient can be stored as map data (e.g. in the form of map data) according to the vehicle speed and vehicle deceleration.

[0017] The tilt movement control can be stopped and ABS control can be performed if the tilt coefficient is less than a second predetermined value.

[0018] According to numerous embodiments of the present invention, it is possible to minimize the braking distance of a vehicle by means of a tilting motion control to minimize the tilting motion during abrupt braking of a vehicle.

[0019] It is understood that the terms "vehicle" or "vehicle-" or other similar terms as used herein include, for general motor vehicles such as passenger vehicles including all-terrain vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft and the like, and hybrid vehicles, electric vehicles, plug-in hybrid vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuels derived from resources other than petroleum). As referenced herein, a hybrid vehicle is a vehicle that has two or more power sources, for example, both gasoline-powered and electric-powered vehicles.

[0020] The methods and devices of the present invention have advantages which are evident from the accompanying drawings included herein and the following detailed description, which together serve to explain certain principles of the present invention, or which are set out in more detail therein. Explanation of the drawings Fig. Figure 1 is a schematic view illustrating a tilting motion generated when a vehicle brakes quickly (or abruptly). Fig. Figure 2 is a block diagram illustrating an exemplary braking device of a vehicle according to the present invention. Fig. Figure 3 is a flowchart illustrating an exemplary braking procedure of a vehicle according to the present invention. Fig. Figure 4 is a graph illustrating a relationship between vehicle deceleration, inclination coefficient, and braking force. Fig. Figure 5 is a graph illustrating a relationship between vehicle speed, braking force, and vehicle deceleration.

[0021] It should be understood that the accompanying drawings are not necessarily to scale and present a somewhat simplified representation of various features that illustrate the basic principles of the invention. The specific design features of the present invention, as disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes, will be determined in part by the particular intended application and operating environment. Detailed description

[0022] Fig. Figure 2 is a block diagram illustrating a braking device of a vehicle according to numerous embodiments of the present invention.

[0023] As in Fig. Figure 2 shows a braking device of a vehicle according to numerous embodiments of the present invention comprising a detector 20 that detects driving information of the vehicle, an anti-lock braking system (ABS) 30 that controls a braking force supplied to the wheels 10 provided on the vehicle by detecting the slip generated at the wheels 10, and a control device 40 that determines a braking state of the vehicle from driving information detected by the detector 20 and selectively performs ABS control or tilting motion control in order to reduce the tilting motion of the vehicle.

[0024] The detector 20 detects general driving information, including the actuation state of the brake pedal, vehicle speed and vehicle deceleration, and the detected driving information is fed to the control device 40.

[0025] The driver's actuation of the brake pedal can be detected by a brake pedal sensor installed in the vehicle. The vehicle speed can be detected by a wheel speed sensor located in wheel 10. The vehicle deceleration can be detected by an acceleration sensor located in wheel 10 or calculated by differentiating the wheel speeds detected by the wheel speed sensor.

[0026] The control device 40 can be implemented by one or more processors which are operated by a predetermined program, wherein the predetermined program is configured to perform steps of a braking procedure of a vehicle according to numerous embodiments of the present invention.

[0027] The control device 40 determines whether the vehicle is braking abruptly based on the actuation state of the brake pedal and the vehicle deceleration. For example, the control device 40 can determine that the vehicle is braking abruptly if the brake pedal is actuated and the vehicle deceleration is greater than a predetermined deceleration.

[0028] The control device 40 calculates a tilt coefficient from the vehicle speed and a change (e.g., magnitude of change) in the vehicle deceleration. The tilt coefficient quantitatively defines a tilting motion phenomenon. The tilt coefficient is stored in the control device 40 as map data (e.g., in the form of map data) according to the vehicle speed and the vehicle deceleration.

[0029] If the inclination coefficient is greater than a first predetermined value, the control device 40 performs an inclination movement control.

[0030] The tilt control system is a method in which the braking force applied to the vehicle's wheels (10) is limited to prevent tilting. Specifically, the tilt control system applies a predetermined braking force to the wheels (10) for a predetermined time and gradually increases the braking force applied to the wheels (10) until the tilt coefficient becomes less than a second predetermined value.

[0031] If the tilt coefficient is less than a second predetermined value, the control device 40 stops the tilt movement control, and if slippage occurs at the wheels 10, the control device 40 executes the ABS control.

[0032] The following section, with reference to the accompanying drawings, explains in detail a braking method for a vehicle according to numerous embodiments of the present invention.

[0033] Fig. Figure 3 is a flowchart illustrating a braking procedure of a vehicle according to numerous embodiments of the present invention. Fig. Figure 4 is a graph illustrating a relationship between vehicle deceleration, inclination coefficient, and braking force.

[0034] Referring to Fig. 3 and Fig. In step S10, the control device 40 uses the detector 20 to determine whether the vehicle is braking.

[0035] It is possible to determine whether the vehicle is braking by means of a signal transmitted by a brake pedal sensor.

[0036] When the vehicle brakes, in step S20 the control device 40 determines, based on a vehicle deceleration detected by the detector 20, whether the vehicle is braking abruptly. At this point, the control device 40 can determine that the vehicle is braking abruptly (see 't1' from ). Fig. 4) if the vehicle's deceleration is greater than a predetermined deceleration (see 'a' from Fig. 4).

[0037] The control device 40 calculates a tilt coefficient in step S30. As explained above, the tilt coefficient can be stored as map data according to the vehicle speed and vehicle deceleration.

[0038] If the slope coefficient is greater than a predetermined value (see ,b' from Fig. 4), the control device 40 determines that the tilting movement has occurred and executes the tilting movement control in step S50 from time 't2'.

[0039] Specifically, the control device 40 applies a predetermined braking force to the wheel (or wheels) 10 for a predetermined time.

[0040] If the tilt coefficient is greater than the second predetermined value, the control device 40 gradually increases the braking force supplied to the wheel 10. If the tilt coefficient is less than the second predetermined value, this means that no tilting movement has occurred. At this point, the second predetermined value is set so that it is less than the first predetermined value.

[0041] In other words, the control device 40 gradually increases the braking force supplied to the wheel 10 from the time when the inclination coefficient is the first predetermined value (see ,b' and ,t2' from Fig. 4) until the point in time when the slope coefficient becomes less than the second predetermined value (see ,c' and ,t3' from Fig. 4).

[0042] This means that the control device 40 begins the tilt movement control when the tilt coefficient is greater than the first predetermined value and carries out the tilt movement control until the tilt coefficient becomes less than the second predetermined value (see 'tilt movement control period' from Fig. 4).

[0043] If, in step S60, the tilt coefficient is smaller than the second predetermined value, the control device 40 stops the tilt movement control.

[0044] The control device 40 detects a wheel condition of the vehicle through the detector 20. If slippage has occurred at wheel 10 in step S70, the control device executes the ABS control in step S80 to prevent wheel slippage and brake locking.

[0045] The braking method of the vehicle according to numerous embodiments of the present invention is explained below by comparing it with a braking method according to conventional technology. The braking method according to conventional technology refers only to ABS control (e.g., only the implementation of ABS control by detecting wheel slip during abrupt braking).

[0046] Fig. Figure 5 is a graph illustrating a relationship between vehicle speed, braking force, and vehicle deceleration.

[0047] If only the ABS control is activated during an abrupt reduction in vehicle speed, then – as in Fig. As shown in Figure 5, a high braking force is applied to wheel 10, and then the braking force is rapidly reduced. This means the wheel speed is quickly decreased and then quickly increased. The vehicle deceleration is increased and then decreased (see 'x' from Figure 5). Fig.5), and the vehicle's braking distance is increased.

[0048] Since the braking method according to the present invention limits the braking force supplied to the wheel (or wheels) 10 by means of the tilting motion control before the ABS control is executed, the vehicle deceleration is reduced and the braking distance is not increased.

[0049] If the vehicle brakes abruptly and the tilt coefficient is greater than the first predetermined value, the control device determines – as explained above – that the tilting movement has occurred, according to numerous embodiments of the present invention, and executes the tilting movement control.

[0050] If the braking force supplied to wheel 10 is gradually increased by the tilting motion control, it is possible to prevent the loss of vehicle deceleration compared to conventional technology.

Claims

[1] A braking device of a vehicle comprising: a detector (20) configured to detect driving information, including the actuation state of a brake pedal, vehicle speed and vehicle deceleration, an anti-lock braking system, ABS, (30) which is configured to control a braking force supplied to the wheels (10) of the vehicle by detecting slip generated at the wheels (10), and a control device (40) configured to determine a braking state of the vehicle from the actuation state of the brake pedal, the vehicle speed and the vehicle deceleration detected by the detector (20), and configured to selectively perform ABS control or tilt movement control to reduce a tilt movement of the vehicle according to the braking state of the vehicle, wherein the control device (40) is configured to perform the tilt motion control when the vehicle deceleration detected by the detector (20) is greater than a predetermined deceleration and a tilt coefficient determined by the vehicle speed and a change in the vehicle deceleration is greater than a first predetermined value, wherein the tilt motion control incrementally increases the braking force supplied to the wheels (10) according to the tilt coefficient until the tilt coefficient becomes less than a second predetermined value after the braking force has been supplied to the wheels (10) for a time period, and where the second predetermined value is smaller than the first predetermined value. [2] The braking device of a vehicle according to claim 1, wherein the control device (40) is configured to stop the tilting motion control when the tilt coefficient is less than the second predetermined value, and performs the ABS control. [3] A braking method of a vehicle comprising: Determine, by means of a control device (40), whether the vehicle is braking (S10), Determine, by means of the control device (40), whether the vehicle is braking abruptly (S20), Determine, by means of the control device (40), a tilt coefficient from a vehicle speed and a vehicle deceleration (S30), Determine, by means of the control device (40), whether the vehicle is braking abruptly and whether the inclination coefficient is greater than a predetermined value (S40), and Performing, by means of the control device (40), a tilt motion control (S50), when the vehicle deceleration is greater than a predetermined deceleration and the tilt coefficient determined by the vehicle speed and a change in the vehicle deceleration is greater than a first predetermined value, wherein the tilt motion control incrementally increases the braking force supplied to the wheels (10) according to the tilt coefficient until the tilt coefficient becomes less than a second predetermined value after the braking force has been supplied to the wheels (10) for a time period, and where the second predetermined value is smaller than the first predetermined value. [4] The braking method of a vehicle according to claim 3, wherein the inclination coefficient is stored as characteristic map data according to the vehicle speed and the vehicle deceleration. [5] The braking method of a vehicle according to one of claims 3 or 4, wherein the tilt motion control is stopped and an ABS control is performed (S80) when the tilt coefficient is less than the second predetermined value.

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