Method and system for shortening braking distance of vehicle and vehicle

Abstract

The invention discloses a method and system for shortening the braking distance of a vehicle and the vehicle, and belongs to the technical field of vehicle braking. The method comprises the following steps that scene information in front of the vehicle is obtained; acquiring a current vehicle speed; according to the scene information and the current vehicle speed, whether a critical collision threshold value is reached or not is judged, if yes, a servo motor at a vehicle chassis is controlled to move up and down, a distance reducing plate is driven by the servo motor to ascend and descend, and the distance reducing plate makes contact with the ground. A new braking force path is added for vehicle braking, the speed of the vehicle is effectively reduced, the braking distance is remarkably shortened, and the capacity of avoiding collision under the emergency condition is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle braking, and more specifically, to a method, a system and a vehicle for shortening a braking distance of a vehicle. Background Art

[0002] The braking system of a car is a key device to ensure the safety of the driver and passengers. With the continuous development of technology, the performance of the braking system has been continuously improved, and the advent of the automatic emergency braking system (AEB) is of great significance. When facing the risk of collision, AEB can automatically start the braking action in advance to effectively avoid or reduce the damage caused by the collision.

[0003] At present, automobile braking systems are mainly divided into two categories: disc type and drum type. The braking principle is usually that the driver presses the brake pedal to make the brake components and wheels work together, thereby reducing the speed of the vehicle to achieve the braking effect. However, in actual driving, conditions such as excessive speed and slippery roads will cause the braking distance to increase significantly, thus causing a collision accident.

[0004] Modern braking systems mainly reduce vehicle speed by controlling the rotation speed of the four wheels. This prior art has certain shortcomings, specifically, the required braking distance from the driver stepping on the pedal until the vehicle stops completely is long. Summary of the invention

[0005] An object of the present invention is to provide a method, system and vehicle for shortening the braking distance of a vehicle, so as to solve the aforementioned problem of long braking distance.

[0006] According to a first aspect of the present invention, there is provided a method for shortening a vehicle braking distance, comprising the following steps:

[0007] Step S100: Acquire scene information in front of the vehicle;

[0008] Step S200: obtaining the current vehicle speed;

[0009] Step S300: judging whether a critical collision threshold is reached according to the scene information and the current vehicle speed, and if so, controlling a servo motor at the vehicle chassis to move up and down, and driving a distance reducing plate to move up and down by the servo motor, so that the distance reducing plate contacts the ground.

[0010] Optionally, the method for shortening the vehicle braking distance further includes:

[0011] Step S400: After the servo motor drives the distance reducing plate to rise and fall and the distance reducing plate contacts the ground, it is determined whether the current vehicle speed is zero. If not, a vehicle body lowering instruction is sent to the air suspension controller so that the vehicle body presses down the distance reducing plate.

[0012] Optionally, after step S200 and before step S300, the following steps are further included:

[0013] The scene information in front of the vehicle is identified. When a set scene object is identified, it is determined whether the longitudinal distance between the set scene object and the vehicle reaches the safety distance threshold. If it does and the driver does not take braking measures, a braking command is sent to the vehicle based on the AEB algorithm to start braking.

[0014] Optionally, in step S300, in the step of controlling the up and down movement of the servo motor at the vehicle chassis, the controller sends a control signal to the servo motor at the vehicle chassis, and the control signal includes motor movement direction, motor movement speed and motor movement stroke information.

[0015] According to a second aspect of the present invention, there is provided a system for shortening the braking distance of a vehicle, using the method for shortening the braking distance of a vehicle according to the first aspect of the present invention, the system comprising a servo motor, a controller and a distance reducing plate;

[0016] The servo motor and the distance reducing plate are both installed on the vehicle chassis, and the servo motor is hard-connected to the distance reducing plate;

[0017] The controller is connected to the servo motor, and is used to determine whether a critical collision threshold is reached based on scene information in front of the vehicle and the current vehicle speed. If so, the controller controls the servo motor to move up and down, and drives the distance reduction plate to rise and fall through the servo motor, so that the distance reduction plate contacts the ground.

[0018] Optionally, the system for shortening the braking distance of the vehicle further comprises an air suspension system, the air suspension system comprising an air suspension controller and an air suspension, the controller is communicatively connected to the air suspension controller via a CAN bus, and the air suspension controller is connected to the air suspension;

[0019] After the servo motor drives the distance reducing plate to rise and fall and the distance reducing plate contacts the ground, the controller determines whether the current vehicle speed is zero. If not, a vehicle body lowering instruction is sent to the air suspension controller to make the vehicle body press down the distance reducing plate.

[0020] Optionally, the distance reducing plate is in the shape of a cuboid or a trapezoid.

[0021] Optionally, the distance reducing plate is made of steel plate.

[0022] Optionally, a layer of rubber is sprayed on the bottom of the distance reducing plate.

[0023] According to a third aspect of the present invention, a vehicle is provided, which adopts the system for shortening the braking distance of the vehicle according to the second aspect of the present invention.

[0024] The method, system and vehicle for shortening the braking distance of a vehicle according to the present disclosure have the following technical effects:

[0025] After obtaining the current vehicle speed, the system can combine the forward scene information to accurately assess the degree of collision risk and calculate how much additional braking force needs to be applied at different stages to effectively shorten the braking distance.

[0026] The setting of the critical collision threshold takes into account many factors such as the vehicle's own braking performance and normal reaction time. Once the threshold is reached, it means that conventional brake disc braking may not be able to avoid a collision or control the braking distance within the ideal range. The servo motor drives the distance reduction plate to rise and fall to make it contact with the ground, adding a new braking force path for vehicle braking. It can further consume the vehicle's kinetic energy on the basis of conventional wheel braking, effectively reduce the vehicle's speed, thereby significantly shortening the braking distance and improving the ability to avoid collisions in emergency situations.

[0027] A vehicle body lowering command is sent to the air suspension controller, causing the vehicle body to press down on the distance reducer, increasing the positive pressure between the distance reducer and the ground. The friction generated between the distance reducer and the ground also increases accordingly, thereby further improving the braking force, helping to reduce the vehicle speed to zero more quickly, further shortening the braking distance, and ensuring to the greatest extent possible that the vehicle can avoid collisions or reduce the severity of collisions when facing danger.

[0028] 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

[0029] 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.

[0030] Figure 1 A schematic flow chart of a method for shortening a vehicle braking distance provided by an embodiment of the present invention;

[0031] Figure 2 A logical schematic diagram of a system for shortening a vehicle braking distance provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] 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.

[0033] 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.

[0034] 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 part of the specification.

[0035] 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.

[0036] The present invention provides an embodiment of a method for shortening a vehicle braking distance. Specifically, Figure 1 As shown, the following steps are included:

[0037] Step S100: Acquire scene information in front of the vehicle;

[0038] Specifically, vehicles are usually equipped with a variety of sensors to obtain information about the scene ahead, which are generally installed near the front grille of the vehicle or above the windshield. Among them, high-definition cameras can capture high-resolution images, and their lens angle of view can cover a certain range in front of the vehicle. The image sensor of the camera can be CMOS or CCD type, which can quickly convert optical signals into electrical signals to meet the needs of real-time monitoring. Some vehicles are equipped with laser radar, which constructs a three-dimensional point cloud map in front of the vehicle by emitting laser beams and detecting reflected light. Laser radar can provide more detailed information on the shape and position of objects, especially in complex road scenes, such as multiple vehicles, pedestrians and obstacles, and can better distinguish the relationship between each object. Some vehicles are equipped with millimeter-wave radar, which accurately calculates the distance, relative speed and angle between the front object and the vehicle by analyzing parameters such as the time difference and frequency change between the transmitted wave and the reflected wave. The data collected by the sensor will be transmitted to the vehicle's controller, and the collected data will be further processed by the controller.

[0039] Step S200: obtaining the current vehicle speed;

[0040] Specifically, the current vehicle speed is obtained through a vehicle speed sensor. There are two types of vehicle speed sensors: one is a sensor based on wheel rotation, installed near the wheel hub or on the brake disc; the other is a sensor based on the transmission output shaft speed, installed on the transmission output shaft.

[0041] Step S300: Based on the scene information and the current vehicle speed, determine whether the critical collision threshold is reached. If so, control the servo motor at the vehicle chassis to move up and down, and drive the distance reduction plate to rise and fall through the servo motor so that the distance reduction plate contacts the ground.

[0042] Specifically, the setting of the critical collision threshold comprehensively considers multiple aspects, including the braking performance of the vehicle, the mass and inertia of the vehicle, and the reaction time of the driver. Among them, the braking performance of the vehicle includes the braking efficiency of the brake disc, the friction coefficient between the tire and the ground, etc. For example, a high-performance car with good braking performance, whose brake disc can provide a large braking force and the adhesion coefficient between the tire and the ground is high, has a relatively small critical collision threshold. It is generally assumed that the normal reaction time of the driver is between 0.5-1.5 seconds. The reaction distance is calculated based on the current speed and reaction time of the vehicle, and then the final critical collision threshold is determined by combining factors such as the maximum deceleration of the braking system and the safety margin. For example, for a vehicle traveling at 60 kilometers per hour (about 16.7 meters per second), assuming that the driver's reaction time is 1 second, the reaction distance is 16.7 meters. If the vehicle's braking system can reduce the speed from 60 kilometers per hour to zero within 40 meters, the critical collision threshold will be set at about 50-60 meters between the vehicle and the obstacle in front to ensure sufficient safety margin.

[0043] When it is determined that the critical collision threshold is reached, the vehicle's controller will send a control signal to the servo motor at the chassis. The control signal specifies that the servo motor rotates downward at a certain speed (such as 100 rpm). The torque output of the servo motor must be sufficient to overcome the gravity and motion resistance of the distance reducing plate, allowing the distance reducing plate to descend smoothly.

[0044] In an embodiment of the present invention, the method for shortening the braking distance of a vehicle further includes:

[0045] Step S400: After the servo motor drives the distance reducing plate to rise and fall and makes the distance reducing plate contact with the ground, determine whether the current vehicle speed is zero. If not, send a vehicle body lowering command to the air suspension controller to make the vehicle body press down on the distance reducing plate and make the distance reducing plate start to contact with the ground, thereby increasing the friction between the distance reducing plate and the ground, thereby reducing the braking distance.

[0046] In the embodiment of the present invention, after step S200 and before step S300, the following steps are further included:

[0047] The scene information in front of the vehicle is identified. When the set scene object is identified, it is determined whether the longitudinal distance between the set scene object and the vehicle reaches the safety distance threshold. If it is and the driver does not take braking measures, a braking command is issued to the vehicle based on the AEB algorithm to start braking the vehicle. Among them, the set scene objects are some pre-set scene objects that need to be focused on, such as pedestrians, bicycles, motorcycles, and vehicles that are moving slowly or stopped in front. Different types of objects are accurately distinguished through complex pattern recognition algorithms and deep learning models, and the position information of the set scene objects in front of the vehicle is marked. The safety distance threshold is a pre-set value, which is determined by comprehensively considering multiple factors such as the vehicle's driving speed, road conditions, and vehicle braking performance. The AEB algorithm calculates the required braking force and braking timing based on factors such as the vehicle's current speed, distance from the target, the target's motion state (such as whether it is stationary, speed and direction), and the friction coefficient of the road surface.

[0048] In an embodiment of the present invention, in step S300, in the step of controlling the up and down movement of the servo motor at the vehicle chassis, the controller sends a control signal to the servo motor at the vehicle chassis, and the control signal includes motor movement direction, motor movement speed and motor movement stroke information.

[0049] The present invention also provides an embodiment of a system for shortening a vehicle braking distance, specifically as follows Figure 2 As shown, the above method for shortening the braking distance of a vehicle is adopted, and the system includes a servo motor, a controller and a distance reduction plate;

[0050] The servo motor and the distance reducing plate are both installed on the chassis of the vehicle, and the servo motor is hard-connected to the distance reducing plate; specifically, the distance reducing plate is connected to the output shaft of the servo motor through two parallel connecting rods, one end of the connecting rod is hinged to the two side edges of the distance reducing plate, and the other end is connected to the eccentric wheel on the output shaft of the servo motor. When the servo motor rotates, the eccentric wheel drives the connecting rod to move, so that the distance reducing plate can be raised and lowered smoothly.

[0051] The controller is connected to the servo motor. The controller is used to determine whether the critical collision threshold is reached according to the scene information in front of the vehicle and the current vehicle speed. If so, the servo motor is controlled to move up and down, and the servo motor drives the distance reduction plate to rise and fall, so that the distance reduction plate contacts the ground. Figure 2 As shown in the middle figure.

[0052] In an embodiment of the present invention, the system for shortening the braking distance of a vehicle further includes an air suspension system, the air suspension system includes an air suspension controller and an air suspension, the controller is communicatively connected to the air suspension controller via a CAN bus, and the air suspension controller is connected to the air suspension;

[0053] After the servo motor drives the distance reducing plate to rise and fall and makes the distance reducing plate contact the ground, the controller determines whether the current vehicle speed is zero. If not, a vehicle body lowering command is sent to the air suspension controller to make the vehicle body press down on the distance reducing plate. Figure 2 As shown in the right figure.

[0054] In the embodiment of the present invention, the distance reducing plate is in the shape of a cuboid or a trapezoid. The shape design of the distance reducing plate should take into account the contact area with the ground, aerodynamics, and adaptability of the vehicle chassis space.

[0055] In the embodiment of the present invention, the distance reducing plate is made of a steel plate, and the distance reducing plate may also be made of other high-strength, wear-resistant metal materials.

[0056] In the embodiment of the present invention, a layer of rubber is sprayed on the bottom of the distance reducing plate. When the distance reducing plate rubs against the ground violently, it will generate high noise, which will cause noise pollution to the passengers in the car. By spraying a layer of rubber on the bottom, both the noise and the damage to the ground can be reduced.

[0057] The present invention also provides an embodiment of a vehicle, which adopts the above-mentioned system for shortening the braking distance of a vehicle. Conventional vehicle braking mainly relies on the friction between the brake disc and the brake pad, while the vehicle of the present invention adds the friction between the distance reducing plate and the ground as an auxiliary braking method. During the braking process, the two braking methods work together to consume the kinetic energy of the vehicle more efficiently. The present invention also dynamically adjusts the braking effect according to the real-time state of the vehicle. If the vehicle cannot be stopped quickly by the contact between the distance reducing plate and the ground alone, the friction between the distance reducing plate and the ground is further increased by sending a vehicle body lowering instruction to the air suspension controller. This dynamic adjustment mechanism can flexibly change the braking strategy according to factors such as the speed of the vehicle and the distance from the obstacle, optimize the braking performance, and ensure that the vehicle can shorten the braking distance as much as possible under various working conditions. The system of the present invention is designed based on the existing architecture and control system of the vehicle, has good compatibility, and can be easily integrated with the existing safety system of the vehicle (such as anti-lock braking system ABS, body stability control system ESC, etc.), further enhancing the overall safety performance of the vehicle.

[0058] 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 method for shortening a vehicle braking distance, characterized in that: The following steps are involved: Step S100: Acquire scene information in front of the vehicle; Step S200: obtaining the current vehicle speed; Step S300: judging whether a critical collision threshold is reached according to the scene information and the current vehicle speed, and if so, controlling a servo motor at the vehicle chassis to move up and down, and driving a distance reducing plate to move up and down by the servo motor, so that the distance reducing plate contacts the ground.

2. The method for shortening the braking distance of a vehicle according to claim 1, characterized in that: Also includes: Step S400: After the servo motor drives the distance reducing plate to rise and fall and the distance reducing plate contacts the ground, it is determined whether the current vehicle speed is zero. If not, a vehicle body lowering instruction is sent to the air suspension controller so that the vehicle body presses down the distance reducing plate.

3. The method for shortening the braking distance of a vehicle according to claim 1, characterized in that: After step S200 and before step S300, the method further includes: The scene information in front of the vehicle is identified. When a set scene object is identified, it is determined whether the longitudinal distance between the set scene object and the vehicle reaches the safety distance threshold. If it does and the driver does not take braking measures, a braking command is sent to the vehicle based on the AEB algorithm to start braking.

4. The method for shortening a vehicle braking distance according to claim 1, characterized in that: In step S300, in the step of controlling the up and down movement of the servo motor at the vehicle chassis, the controller sends a control signal to the servo motor at the vehicle chassis, wherein the control signal includes information on the motor movement direction, motor movement speed, and motor movement stroke.

5. A system for shortening the braking distance of a vehicle, using the method for shortening the braking distance of a vehicle according to any one of claims 1 to 4, characterized in that: The system includes a servo motor, a controller and a distance reducing plate; The servo motor and the distance reducing plate are both installed on the vehicle chassis, and the servo motor is hard-connected to the distance reducing plate; The controller is connected to the servo motor, and is used to determine whether a critical collision threshold is reached based on scene information in front of the vehicle and the current vehicle speed. If so, the controller controls the servo motor to move up and down, and drives the distance reduction plate to rise and fall through the servo motor, so that the distance reduction plate contacts the ground.

6. The system for shortening the braking distance of a vehicle according to claim 5, characterized in that: Also includes an air suspension system, the air suspension system includes an air suspension controller and an air suspension, the controller is communicatively connected to the air suspension controller via a CAN bus, and the air suspension controller is connected to the air suspension; After the servo motor drives the distance reducing plate to rise and fall and the distance reducing plate contacts the ground, the controller determines whether the current vehicle speed is zero. If not, a vehicle body lowering instruction is sent to the air suspension controller to make the vehicle body press down the distance reducing plate.

7. The system for shortening the braking distance of a vehicle according to claim 5, characterized in that: The distance reducing plate is in the shape of a cuboid or a trapezoid.

8. The system for shortening the braking distance of a vehicle according to claim 5, characterized in that: The distance reducing plate is made of steel plate.

9. The system for shortening the braking distance of a vehicle according to claim 5, characterized in that: A layer of rubber is sprayed on the bottom of the distance reducing plate.

10. A vehicle, characterized in that: A system for shortening a vehicle braking distance as claimed in any one of claims 5 to 9.

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