Vehicle braking performance control method and system based on multi-sensor detection fusion

Abstract

The invention discloses a vehicle braking performance control method and system based on multi-sensor detection fusion, and belongs to the technical field of vehicle braking, and the method comprises the steps: building a basic braking force function of vehicle braking control under a normal road condition; obtaining road surface sensing parameters collected by at least two sensors; based on the road surface sensing parameters, constructing a road surface slippery degree function used for evaluating the current road slippery degree; according to the basic braking force function and the road surface slippery degree function, a braking force function of the current road is obtained through calculation; and controlling the braking force of the vehicle based on the braking force function of the current road. The vehicle braking force can be dynamically adjusted according to the real-time road condition, the vehicle braking performance weakening early warning function is achieved, and a driver can visually master the current braking performance.

Description

Technical Field

[0001] The present invention relates to the field of vehicle braking technology, and more specifically, to a vehicle braking performance control method and system based on multi-sensor detection fusion. Background Art

[0002] At present, the vehicle's assisted driving and intelligent driving systems mainly include perception modules and regulatory control modules. At the perception level, the perception field of the entire vehicle is constructed with the help of cameras, lidar and other equipment to perform perception tasks such as pedestrian detection and lane line detection. After receiving the perception information, the control end generates vehicle posture control instructions based on the obstacle information, road surface information, etc., which includes braking control instructions. For example, when the adaptive cruise control system (ACC) is running, it can adjust the acceleration and deceleration of the vehicle according to the distance from the vehicle in front, and implement braking control on the vehicle in an emergency.

[0003] However, in unconventional weather conditions such as rain and snow, the braking distance of the vehicle may change, making it difficult for the driver or the vehicle to accurately control the braking distance, which in turn creates safety risks. In existing scenarios, the determination of braking force mostly relies on the driver's experience. For example, when the vehicle speed reaches 100km / h and the distance from the vehicle in front is 100m, the driver usually judges the force required to apply to the brake pedal to brake the vehicle based on habit. However, under extreme road conditions, it is often difficult for drivers to accurately assess the impact of the road surface on the braking effect. If they still brake according to the habit of conventional roads, it is very likely that the braking distance will be insufficient or the wheels will slip due to excessive braking force.

[0004] The prior art has the following defects:

[0005] First, it is impossible to dynamically adjust the vehicle's braking level under extreme road conditions (different weather road conditions and different tire conditions) to optimize braking performance in real time.

[0006] Second, the assisted driving function lacks the function of controlling the current braking performance. For example, in a rainy environment, the vehicle does not indicate that the braking performance has been reduced on the current slippery road, causing the driver to misjudge that the current braking performance is the same as on a dry road, thus posing a safety hazard.

[0007] Third, the assisted driving function does not provide the current recommended braking performance indicators. Drivers are often unclear about the optimal braking force for the vehicle under specific road conditions. For example, on slippery roads, drivers often apply a lot of force to the brake pedal based on past experience. Although the brakes can be successfully applied on dry roads, the excessive braking force may cause the vehicle to slip on slippery roads, causing danger. Summary of the invention

[0008] The purpose of the present invention is to provide a vehicle braking performance control method and system based on multi-sensor detection fusion to solve the problem that the braking force of existing vehicles cannot be dynamically adjusted according to real-time road conditions, the current assisted driving does not have a warning function for the weakening of vehicle braking performance, and the current assisted driving does not have a recommended indicator for the current vehicle braking force.

[0009] According to a first aspect of the present invention, a vehicle braking performance control method based on multi-sensor detection fusion is provided, comprising:

[0010] Establishing the basic braking force function for vehicle braking control under normal road conditions;

[0011] Acquire road surface sensing parameters collected by at least two sensors;

[0012] Based on the road surface sensing parameters, constructing a road surface slipperiness function for evaluating the current road slipperiness;

[0013] Calculating a braking force function of a current road according to the basic braking force function and the road surface slipperiness function;

[0014] The braking force of the vehicle is controlled based on the braking force function of the current road.

[0015] Optionally, in the step of establishing a basic braking force function for vehicle braking control, the basic braking force function is set to Y, the distance between the current vehicle and the preceding vehicle is set to X1, and the speed of the preceding vehicle is set to X2, then:

[0016] Y = AX1 + BX2, where A and B are proportional coefficients preset based on expert experience.

[0017] Optionally, in the step of acquiring road surface sensing parameters collected by at least two sensors, the sensors include a rain sensor and a front-view camera.

[0018] Optionally, the data collected by the rain sensor is set to x, the data collected by the front-view camera is set to y, and the road surface slipperiness function for evaluating the current road slipperiness is set to Y1, then:

[0019] Y1=ax+by, where a and b are proportional coefficients preset based on expert experience.

[0020] Optionally, in the step of calculating the braking force function of the current road according to the basic braking force function and the road surface slipperiness function, the braking force function of the current road is set to Y 合 ,but:

[0021] Y 合=Y+CY1=AX1+BX2+CY1, where C is the proportional coefficient preset based on expert experience.

[0022] Optionally, the vehicle braking performance control method based on multi-sensor detection fusion further includes:

[0023] Get the braking distance required to completely stop the vehicle under normal road conditions, set to Z;

[0024] Get the braking distance required to completely stop the vehicle under the current road conditions, set to Z1;

[0025] Set the percentage of the extended braking distance warning level to W, then:

[0026] W=(Z1-Z) / Z*100%.

[0027] Optionally, multiple percentage intervals of braking distance extension warning degree are set, including [0, 30%], [30%, 50%] and greater than 50%.

[0028] Optionally, when the percentage of the extended braking distance warning degree is in the range of [0, 30%], only the instrument panel is triggered to display the warning information;

[0029] When the percentage of the extended braking distance warning is in the range of [30%, 50%], the ambient light will light up and the information on the instrument panel will flash;

[0030] When the percentage of extended braking distance warning is greater than 50%, the ambient light is triggered to flash red, and the instrument panel and vehicle display screen both flash red.

[0031] According to a second aspect of the present invention, a vehicle braking performance control system based on multi-sensor detection fusion is provided, comprising:

[0032] A first function determination module is used to establish a basic braking force function for vehicle braking control under normal road conditions;

[0033] A parameter acquisition module, used to acquire road surface sensing parameters acquired by at least two sensors;

[0034] A second function determination module is used to construct a road surface slipperiness function for evaluating the current road slipperiness based on the road surface sensing parameters;

[0035] A third function determination module is used to calculate and obtain the braking force function of the current road according to the basic braking force function and the road surface slipperiness function;

[0036] The execution module is used to control the braking force of the vehicle based on the braking force function of the current road.

[0037] Optionally, the vehicle braking performance control system based on multi-sensor detection fusion also includes:

[0038] The braking warning module is used to obtain the percentage of the braking distance extension warning degree, and trigger the corresponding warning device according to the interval in which the braking distance extension warning degree percentage is located.

[0039] The vehicle braking performance control method and system based on multi-sensor detection fusion disclosed in the present invention have the following technical effects:

[0040] Based on the road sensing parameters collected by the rain sensor and the front-view camera, a road slipperiness function is constructed to evaluate the current road slipperiness; according to the basic braking force function and the road slipperiness function, the braking force function of the current road is calculated. In autonomous driving, the braking performance can be dynamically changed according to different weather and road conditions, so that the vehicle can adapt to different scenarios.

[0041] The corresponding warning device can be triggered according to the interval of the percentage of the extended warning degree of the braking distance. The driver can be informed of the dynamic braking performance of the vehicle in advance. When the braking performance of the vehicle is reduced due to certain road reasons or vehicle reasons, the driver can receive information in advance.

[0042] The vehicle's braking performance can be displayed to the driver in a numerical and visual manner on the screen, allowing the driver to intuitively understand whether the vehicle's braking performance has only declined slightly or has declined significantly, helping the driver to better control the car.

[0043] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0045] Figure 1 A schematic flow chart of a vehicle braking performance control method based on multi-sensor detection fusion provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0047] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0048] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0049] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0050] The present invention proposes an embodiment of a vehicle braking performance control method based on multi-sensor detection fusion. Specifically, Figure 1 shown, including:

[0051] Establishing a basic braking force function for vehicle braking control under normal road conditions; specifically, the normal road condition may refer to a dry road surface;

[0052] In the embodiment of the present invention, in the step of establishing the basic braking force function of vehicle braking control, the basic braking force function is set to Y, the distance between the current vehicle and the preceding vehicle is set to X1, and the speed of the preceding vehicle is set to X2, then:

[0053] Y = AX1 + BX2, where A and B are proportional coefficients preset based on expert experience, specifically proportional coefficients set based on a large amount of actual driving data and experience.

[0054] Based on the road surface sensing parameters, constructing a road surface slipperiness function for evaluating the current road slipperiness;

[0055] In the embodiment of the present invention, the data collected by the rain sensor is set to x, the data collected by the front-view camera is set to y, and the road surface slipperiness function used to evaluate the current road slipperiness is set to Y1, then:

[0056] Y1=ax+by, where a and b are proportional coefficients preset based on expert experience, specifically weight coefficients determined based on sensor characteristics and a large number of experiments.

[0057] Obtain road sensing parameters collected by at least two sensors; specifically, at least two sensors include a rain sensor and a front-view camera, the rain sensor senses the amount of rain to assess the slippery condition on the road, and the front-view camera detects the brightness of the road's reflection or the water puddle to determine the water accumulation condition on the road. In addition, the slippery condition of the road can also be determined by multiple other sensors on the vehicle body. In addition to the above sensors, the tire pressure sensor can also indirectly provide road information. Under different road conditions, the friction between the tire and the road is different, which will cause a slight change in tire pressure. For example, on a slippery road, the tire grip decreases, and the tire will have a slight deformation, causing fluctuations in tire pressure. By monitoring the numerical changes of the tire pressure sensor and combining other sensor data, the road condition can be judged more accurately. Specifically, the tire pressure sensor data is set to z, Y1=ax+by+ez, where e is a proportional coefficient preset based on expert experience, specifically a weight coefficient determined based on sensor characteristics and a large number of experiments.

[0058] According to the basic braking force function and the road slipperiness function, the braking force function of the current road is calculated; specifically, the braking force function of the current road is set to Y 合 ,but:

[0059] Y 合 =Y+CY1=AX1+BX2+CY1, where C is the proportional coefficient preset based on expert experience.

[0060] The braking force of the vehicle is controlled based on the braking force function of the current road. The vehicle control end (such as the electronic control unit ECU) can accurately calculate and adjust the braking force based on the current distance between the vehicle and the vehicle in front (X1), the speed of the vehicle in front (X2) and the real-time road slipperiness (Y1).

[0061] By adding these additional conditions and corresponding functions, the braking control function is more in line with the actual complex road conditions, and can dynamically adjust the braking force in real time according to different weather, road and tire conditions, greatly improving the accuracy and safety of vehicle braking. Whether in wet rainy days, slippery snow, or changes in grip due to tire wear, the vehicle can more reasonably control the braking force, effectively avoiding traffic accidents caused by insufficient or excessive braking, and enhancing the adaptability of the vehicle under various working conditions.

[0062] It should be noted that during vehicle driving, as the road surface sensing parameters change in real time, the value of the road surface slipperiness function Y1 will also change dynamically, which will lead to the braking force function Y 合For example, when a vehicle suddenly enters a road with a lot of water during driving, the rain sensor and the front-view camera detect that the road slipperiness increases sharply, and the value of the road slipperiness function Y1 rises rapidly. At this time, the braking force function Y 合 The braking force will be adjusted immediately so that the vehicle can adjust the braking operation in time according to the actual road conditions to ensure the safety and effectiveness of braking.

[0063] On the other hand, a series of safety measures are set in the process of braking force control based on the braking force function of the current road. For example, the upper and lower limits of the braking force are set to prevent the dangerous situation of vehicle loss of control or insufficient braking caused by excessive or insufficient braking force due to sensor failure or calculation error.

[0064] In an embodiment of the present invention, the vehicle braking performance control method based on multi-sensor detection fusion also includes:

[0065] The braking distance required to completely stop the vehicle under normal road conditions is obtained and set to Z. Specifically, when the road surface is dry and the friction is within the normal standard range, the distance the vehicle travels from braking at a certain speed to completely stopping is the braking distance (Z) under normal road conditions.

[0066] Get the braking distance required to completely stop the vehicle under the current road conditions, which is set as Z1. Specifically, under the influence of multiple factors such as weather (such as rain, snow, fog, etc.), road conditions (such as water accumulation, ice, potholes, etc.), and tire wear, the distance that the vehicle travels when braking from a certain speed to a complete stop under such actual road conditions is Z1.

[0067] Set the percentage of the extended braking distance warning level to W, then:

[0068] W=(Z1-Z) / Z*100%.

[0069] The above formula is intended to compare the difference between the braking distance (Z1) under the current road conditions and the braking distance (Z) under normal road conditions, and to calculate the percentage of this difference to Z based on the braking distance (Z) under normal road conditions, so as to intuitively reflect the extent to which the braking distance is extended due to the deterioration of the current road conditions. For example, if W=30% is calculated, it means that under the current road conditions, the braking distance of the vehicle is extended by 30% compared to the normal road.

[0070] By calculating the percentage of the extended braking distance warning degree (W), the driver or the vehicle's intelligent control system can be shown in an intuitive and quantitative way how much the current road conditions affect the braking performance compared to normal roads. The driver can clearly understand how much longer the braking distance has become under the current road conditions, and then make psychological preparations in advance and take corresponding driving actions (such as increasing the following distance, reducing the speed, etc.) to ensure driving safety.

[0071] In the embodiment of the present invention, a plurality of percentage intervals of the degree of warning of the extended braking distance are set, including [0, 30%], [30%, 50%] and greater than 50%.

[0072] When the percentage of the extended braking distance warning degree is in the range of [0, 30%], it indicates that the extended braking distance is relatively small, and only the instrument panel is triggered to display the warning information, issuing a slight warning to remind the driver that the road conditions have changed slightly but are still within the controllable range;

[0073] When the percentage of the extended braking distance warning level is in the range of [30%, 50%], the ambient light will light up and the information on the instrument panel will flash, indicating a moderate warning, prompting drivers to drive more cautiously and increase the following distance appropriately.

[0074] When the percentage of the extended braking distance warning degree is greater than 50%, it is a high warning, which triggers the ambient light to flash red, and the instrument panel and the on-board display screen to flash red. At the same time, the vehicle control system itself can also take emergency response measures, such as actively reducing the speed, preparing for greater braking force in advance, etc. Through this graded warning and targeted measures, it can more effectively deal with the impact of different degrees of road conditions on braking performance and ensure driving safety in all aspects.

[0075] The embodiment of the present invention realizes a graded reminder function according to the degree of influence of road conditions on braking performance by dividing different percentage intervals of warning degree of extended braking distance and corresponding different warning trigger mechanisms. It can accurately convey warning information of corresponding intensity to the driver according to the severity of actual road conditions, avoiding the disadvantages of using the same strong or weak warning method regardless of the impact of road conditions.

[0076] On the other hand, under special road conditions, the driver has learned through the interactive interface that the braking performance is reduced and the braking distance is extended. At this time, the present invention can also provide the driver with a braking rating display on the interactive interface. On dry roads, the recommended braking force displayed on the interactive interface is level 6, but under special road conditions, the recommended braking force is level 7. The driver can intuitively feel the change in the braking performance parameters, which is conducive to the driver having a better intuitive grasp of the current braking performance of the vehicle.

[0077] The present invention also provides an embodiment of a vehicle braking performance control system based on multi-sensor detection fusion, comprising:

[0078] A first function determination module is used to establish a basic braking force function for vehicle braking control under normal road conditions;

[0079] A parameter acquisition module, used to acquire road surface sensing parameters acquired by at least two sensors;

[0080] A second function determination module is used to construct a road surface slipperiness function for evaluating the current road slipperiness based on the road surface sensing parameters;

[0081] A third function determination module is used to calculate and obtain the braking force function of the current road according to the basic braking force function and the road surface slipperiness function;

[0082] The execution module is used to control the braking force of the vehicle based on the braking force function of the current road.

[0083] In an embodiment of the present invention, the vehicle braking performance control system based on multi-sensor detection fusion further includes:

[0084] The braking warning module is used to obtain the percentage of the braking distance extension warning degree, and trigger the corresponding warning device according to the interval in which the braking distance extension warning degree percentage is located.

[0085] In summary, in the autonomous driving mode, the vehicle's braking performance can be dynamically adjusted according to different weather and road conditions, ensuring that the vehicle has good adaptability and resilience in a variety of driving scenarios. It can help the driver know the dynamic changes in the vehicle's braking performance in advance, so that the driver can be mentally prepared and plan response strategies in advance, and enhance the driver's control and predictive ability of the vehicle's driving conditions. It can enable the driver to accurately grasp the current vehicle's braking performance in an intuitive way.

[0086] It should be noted that the information interaction, execution process and other contents between the above-mentioned modules are based on the same concept as the method embodiment of the present application, and are devices corresponding to the above-mentioned vehicle braking performance control method based on multi-sensor detection fusion. All implementation methods in the above-mentioned method embodiment are applicable to the embodiments of the device. Its specific functions and technical effects brought about can be found in the method embodiment part, which will not be repeated here.

[0087] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings, but the above is only a preferred embodiment of the present invention. It should be noted that the technical features involved in the above embodiments and their preferred methods can be reasonably combined and matched into a variety of equivalent schemes by those skilled in the art without departing from or changing the design ideas and technical effects of the present invention; therefore, the present invention is not limited to the scope of implementation shown in the drawings, and all changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification and drawings, should be within the protection scope of the present invention.

Claims

1. A vehicle braking performance control method based on multi-sensor detection fusion, characterized in that: include: Establishing the basic braking force function for vehicle braking control under normal road conditions; Acquire road surface sensing parameters collected by at least two sensors; Based on the road surface sensing parameters, constructing a road surface slipperiness function for evaluating the current road slipperiness; Calculating a braking force function of a current road according to the basic braking force function and the road surface slipperiness function; The braking force of the vehicle is controlled based on the braking force function of the current road.

2. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 1 is characterized in that: In the step of establishing the basic braking force function of vehicle braking control, the basic braking force function is set to Y, the distance between the current vehicle and the preceding vehicle is set to X1, and the speed of the preceding vehicle is set to X2, then: Y = AX1 + BX2, where A and B are proportional coefficients preset based on expert experience.

3. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 1, characterized in that: In the step of acquiring road surface sensing parameters collected by at least two sensors, the sensors include a rain sensor and a front-view camera.

4. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 3 is characterized in that: The data collected by the rain sensor is set as x, the data collected by the front-view camera is set as y, and the road surface slipperiness function used to evaluate the current road slipperiness is set as Y1, then: Y1=ax+by, where a and b are proportional coefficients preset based on expert experience.

5. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 4 is characterized in that: In the step of calculating the braking force function of the current road according to the basic braking force function and the road surface slipperiness function, the braking force function of the current road is set to Y 合 ,but: Y 合 =Y+CY1=AX1+BX2+CY1, where C is the proportional coefficient preset based on expert experience.

6. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 1, characterized in that: Also includes: Get the braking distance required to completely stop the vehicle under normal road conditions, set to Z; Get the braking distance required to completely stop the vehicle under the current road conditions, set to Z1; Set the percentage of the extended braking distance warning level to W, then: W=(Z1-Z) / Z*100%.

7. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 6 is characterized in that: Set multiple percentage intervals of braking distance extension warning degree, including [0, 30%], [30%, 50%] and greater than 50%.

8. The vehicle braking performance control method based on multi-sensor detection fusion according to claim 7 is characterized in that: When the percentage of the extended braking distance warning degree is in the range of [0, 30%], only the instrument panel is triggered to display the warning information; When the percentage of the extended braking distance warning is in the range of [30%, 50%], the ambient light will light up and the information on the instrument panel will flash; When the percentage of extended braking distance warning is greater than 50%, the ambient light is triggered to flash red, and the instrument panel and vehicle display screen both flash red.

9. A vehicle braking performance control system based on multi-sensor detection fusion, used for vehicle braking control, characterized in that: include: A first function determination module is used to establish a basic braking force function for vehicle braking control under normal road conditions; A parameter acquisition module, used to acquire road surface sensing parameters acquired by at least two sensors; A second function determination module is used to construct a road surface slipperiness function for evaluating the current road slipperiness based on the road surface sensing parameters; A third function determination module is used to calculate and obtain the braking force function of the current road according to the basic braking force function and the road surface slipperiness function; The execution module is used to control the braking force of the vehicle based on the braking force function of the current road.

10. The vehicle braking performance control system based on multi-sensor detection fusion according to claim 9, characterized in that: Also includes: The braking warning module is used to obtain the percentage of the braking distance extension warning degree, and trigger the corresponding warning device according to the interval in which the braking distance extension warning degree percentage is located.

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