A method, system and vehicle for vehicle bottoming-out warning

Abstract

This application discloses a vehicle bottoming-out warning method, system, and vehicle, relating to the field of vehicle safety control. The method includes: calculating the ground clearance of the lower edge of the bumper based on a preset three-dimensional model of the bumper, vehicle body state parameters, and driving plane elevation data; comparing the difference between the ground clearance and the height of a target obstacle collected by a sensor array located on the lower edge of the bumper with a preset risk distance interval to determine the collision risk level and execute the corresponding preset risk warning action. This application, based on the target obstacle height collected by the sensor array located on the lower edge of the bumper, avoids the influence of the external environment on the accuracy of pre-data collection. Furthermore, it determines the collision risk level based on the difference between the ground clearance and the target obstacle height at the current moment, reducing the risk of false alarms. Finally, it executes the preset risk warning action corresponding to the collision risk level, achieving differentiated warning intervention and improving the accuracy of vehicle bottoming-out warnings and vehicle driving safety.

Description

Technical Field

[0001] This application relates to the field of vehicle safety control technology, and in particular to a vehicle bottoming-out warning method, system and vehicle. Background Technology

[0002] In driving scenarios, obstacles such as speed bumps, road shoulders, and fallen objects can easily cause the lower edge of the vehicle's bumper to collide or scrape against the driving surface or obstacle, leading to a bottoming-out accident. While such bottoming-out accidents do not necessarily damage the powertrain or high-voltage system, devices such as millimeter-wave radar, perimeter cameras, sensors, and aerodynamic components are often integrated into the bumper. This makes these devices susceptible to damage or malfunction during a bottoming-out accident, affecting vehicle reliability. Therefore, to provide early warning of bottoming-out accidents, existing bottoming-out warning methods mostly rely on the vehicle's built-in perimeter sensors (such as millimeter-wave radar and lidar) to scan for potential obstacles in the vehicle's direction of movement.

[0003] However, existing vehicle perimeter sensors are susceptible to accuracy degradation due to vehicle speed and external environmental factors (such as rain and snow). Furthermore, these sensors can only detect the presence of obstacles and their distance from the vehicle, leading to a risk of false alarms in current undercarriage warning systems. Therefore, existing undercarriage warning methods cannot provide accurate warnings. Summary of the Invention

[0004] In view of the above problems, this application provides a vehicle bottoming-out warning method, system, and vehicle to improve the accuracy of vehicle bottoming-out warning. The specific solution is as follows:

[0005] The first aspect of this application provides a vehicle bottoming-out warning method, applied to a controller of a vehicle bottoming-out warning system. The vehicle bottoming-out warning system further includes a sensor array disposed at the lower edge of the bumper for measuring the ground clearance of the lower edge of the bumper. The vehicle bottoming-out warning method includes:

[0006] Obtain the height of the target obstacle collected by the sensor array at the current moment, as well as the vehicle body state parameters and driving plane elevation data at the current moment;

[0007] Based on the preset 3D model of the bumper, the vehicle body state parameters, and the driving plane elevation data, the ground clearance of the lower edge of the bumper at the current moment is calculated.

[0008] Calculate the difference between the ground clearance and the height of the target obstacle. Based on the comparison between the difference and the preset risk distance range, determine the collision risk level and execute the preset risk warning action corresponding to the collision risk level.

[0009] In one possible implementation, calculating the ground clearance of the lower edge of the bumper at the current moment based on a preset three-dimensional model of the bumper, the vehicle body state parameters, and the driving plane elevation data includes:

[0010] Based on the vehicle body state parameters, the preset three-dimensional model of the bumper is mapped from the vehicle space coordinate system to the world coordinate system;

[0011] Based on the driving plane elevation data, a ground elevation interpolation function is constructed, and the ground clearance is calculated using the ground elevation interpolation function based on the preset three-dimensional model of the bumper in the world coordinate system.

[0012] In one possible implementation, the vehicle body state parameters include: vehicle attitude angle, vehicle load, vehicle basic parameters, and suspension travel. The mapping of the preset bumper 3D model from the vehicle space coordinate system to the world coordinate system based on the vehicle body state parameters includes:

[0013] The vehicle attitude angle is corrected based on the vehicle load, the vehicle basic parameters, and the suspension travel.

[0014] Based on the corrected vehicle attitude angles, construct a homogeneous transformation matrix from the vehicle space coordinate system to the world coordinate system;

[0015] Based on the homogeneous transformation matrix, each discrete point on the lower edge surface of the pre-set bumper 3D model in the vehicle spatial coordinate system is mapped to the world coordinate system.

[0016] In one possible implementation, the vehicle's basic parameters include suspension stiffness, track width, and wheelbase. The correction of the vehicle attitude angle based on the vehicle load, the vehicle's basic parameters, and the suspension travel includes:

[0017] The suspension static compression is obtained based on the vehicle load and the suspension stiffness, and the suspension travel is updated using the suspension static compression.

[0018] Based on the track width and the updated suspension travel, calculate the roll angle correction; based on the wheelbase and the updated suspension travel, calculate the pitch angle correction.

[0019] Based on the roll angle correction and the pitch angle correction, the roll angle and pitch angle in the vehicle attitude angle are superimposed and corrected respectively.

[0020] In one possible implementation, the vehicle attitude angles include roll angle, pitch angle, and yaw angle. The step of constructing a homogeneous transformation matrix from the vehicle spatial coordinate system to the world coordinate system based on the corrected vehicle attitude angles includes:

[0021] The rotation matrices for the roll angle, pitch angle and yaw angle are constructed respectively, and the product of the rotation matrices is determined as the initial homogeneous transformation matrix;

[0022] The origin coordinates of the world coordinate system are used as a column of data. Based on the column of data, the initial homogeneous transformation matrix is ​​augmented to obtain the homogeneous transformation matrix.

[0023] In one possible implementation, the step of constructing a ground elevation interpolation function based on the driving plane elevation data, and using the ground elevation interpolation function to calculate the ground clearance based on the preset bumper 3D model in the world coordinate system, includes:

[0024] Map the driving plane elevation data to a set of discrete ground points in the world coordinate system;

[0025] The ground elevation interpolation function is constructed based on the set of discrete ground points using a preset interpolation algorithm. The input of the ground elevation interpolation function is the coordinates of the discrete points in the world coordinate system, and the output of the ground elevation interpolation function is the initial ground clearance corresponding to the discrete points.

[0026] The minimum value among the initial ground clearances is determined as the ground clearance of the lower edge of the bumper at the current moment.

[0027] In one possible implementation, the collision risk level includes: a high collision risk level where the difference is less than the lower limit of the preset risk distance interval; and when the collision risk level is the high collision risk level, executing the preset risk warning action corresponding to the collision risk level includes:

[0028] Collect the vehicle speed at the current moment, and the distance between the vehicle and the target obstacle at the current moment;

[0029] When the distance is less than the safe distance threshold and the vehicle speed is less than the preset safe vehicle speed threshold, a braking trigger signal is sent to the braking system.

[0030] If the distance is not less than the safe distance threshold and / or the vehicle speed is not less than the preset safe vehicle speed threshold, a deceleration trigger signal is sent to the adaptive cycle control system.

[0031] A second aspect of this application provides a vehicle bottoming-out warning system, comprising:

[0032] A sensor array, and a controller for performing the vehicle bottoming warning method as described in the first aspect and any implementation thereof, wherein the sensor array is disposed at the lower edge of the bumper;

[0033] The sensor array is communicatively connected to the controller.

[0034] In one possible implementation, the sensor array includes:

[0035] Multiple height sensors are mounted on the vehicle's bumper in a direction perpendicular to the static tire contact surface, with the probe plane of the height sensor being flush with the plane of the lower edge of the bumper, and the height sensors are installed at intervals.

[0036] A third aspect of this application provides a vehicle, including: a vehicle bottoming-out warning system as described in the second aspect and any implementation thereof.

[0037] By employing the aforementioned technical solution, this application provides a vehicle bottom-out warning method, system, and vehicle. This method utilizes a longitudinal sensor array positioned at the bottom edge of the bumper to collect the height of target obstacles at the current moment, enabling the acquisition of heights of obstacles with potential collision risks. Furthermore, by placing the longitudinal sensor array at the bottom edge of the bumper, the bumper shields the sensor array, avoiding the influence of the external environment on the sensor sampling accuracy and further improving subsequent detection accuracy. Moreover, by configuring a preset 3D model of the bumper, vehicle body state parameters, and driving plane elevation data, the method achieves dynamic and accurate calculation of the ground clearance at the bottom edge of the bumper at the current moment. Subsequently, by configuring the calculation of the difference between the ground clearance and the height of the target obstacle, and comparing the difference with a preset risk distance range, the method determines the collision risk level, achieving accurate detection of different degrees of collision risk between the target obstacle and the bumper, reducing the risk of false alarms. Finally, by configuring the execution of preset risk warning actions corresponding to the collision risk level, the method achieves differentiated warning intervention for different collision risks, improving vehicle driving safety. Therefore, this application significantly improves the accuracy of vehicle bottom-out warnings and vehicle driving safety. Attached Figure Description

[0038] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0039] Figure 1 A flowchart of a vehicle bottoming-out warning method provided in this application;

[0040] Figure 2 This application provides a structural schematic diagram of an existing front bumper;

[0041] Figure 3 A schematic diagram of the structure of a front bumper provided in this application;

[0042] Figure 4 This application provides a schematic diagram of the detection range of an existing vehicle perimeter sensor.

[0043] Figure 5 This application provides a schematic diagram of the structure of a sensor array;

[0044] Figure 6 A schematic diagram illustrating a scenario for detecting a bottoming-out accident, as provided in this application;

[0045] Figure 7 A schematic diagram of the vehicle body state provided in this application;

[0046] Figure 8 A flowchart of a vehicle bottoming-out warning method provided in this application;

[0047] Figure 9 This is a schematic diagram of the structure of a controller provided in this application. Detailed Implementation

[0048] The embodiments of this application are described below with reference to the accompanying drawings. The terminology used in the implementation section of this application is for explaining specific embodiments only and is not intended to limit the scope of this application.

[0049] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0050] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0051] The first aspect of this application provides a vehicle bottoming-out warning method, applied to the controller of a vehicle bottoming-out warning system. The vehicle bottoming-out warning system further includes a sensor array disposed at the lower edge of the bumper for measuring the ground clearance of the lower edge of the bumper, such as... Figure 1 The diagram shows a flowchart of the vehicle bottoming-out warning method described above. The vehicle bottoming-out warning method includes:

[0052] S101. Obtain the height of the target obstacle collected by the sensor array at the current moment, as well as the vehicle body status parameters and driving plane elevation data at the current moment.

[0053] It should be noted that in practical applications, the aforementioned lower edge of the bumper refers to the edge position below the bumper. This application, by placing the sensor array along the lower edge of the bumper, reduces the impact of the external environment on the sensor measurement accuracy compared to existing technologies that use perimeter sensors for bottom-out warnings. Specifically: a schematic diagram of the existing front bumper structure is shown below. Figure 2 As shown, by Figure 2 It is known that, since the existing vehicle perimeter sensors 22 are typically deployed on the windward side of the front bumper 21, when the vehicle is in motion, external foreign objects (such as rain, snow, dust) 23 will travel along the windward side of the vehicle. Figure 2 The direction indicated by the middle arrow covers the sensors around the vehicle, thus reducing the measurement accuracy of the sensors. A schematic diagram of the front bumper equipped with the sensor array provided in this application is shown below. Figure 3 As shown, the sensor array 24 is located on the lower edge 25 of the front bumper 21, and is therefore... Figure 3 As shown, when the vehicle is in motion, foreign objects (such as rain, snow, dust) 23 will move along the path shown. Figure 3 The direction indicated by the middle arrow covers the windward side of the front bumper. Since the sensor array 24 is located on the lower edge 25 of the front bumper 21, the sampling port of the sensor array is difficult to be directly covered by foreign objects under the shielding of the front bumper 21, thereby reducing the impact of the external environment on the sensor measurement accuracy.

[0054] Furthermore, the aforementioned sensor array includes multiple height sensors, and the sensor array can be distributed at different positions along the lower edge of the bumper, thereby avoiding the risk of sensor measurement accuracy degradation caused by foreign objects kicked up by the vehicle's wheels covering all the height sensors during vehicle operation.

[0055] It should be noted that in practical applications, existing vehicle perimeter sensors can only detect the presence of obstacles and their distance from the vehicle, leading to a risk of false alarms in existing undercarriage collision warning methods. Specifically, a schematic diagram of the detection range of an existing vehicle perimeter sensor is shown below. Figure 4 As shown. By Figure 4 It is known that existing vehicle perimeter sensors used for undercarriage warning mainly fall into two categories: lidar 41 mounted on the vehicle roof and ultrasonic parking radar 42 mounted on the bumper. While lidar 41 offers good measurement accuracy, its primary use in driver assistance and its typical roof-mounted location result in significant blind spots due to obstruction from the front structure of the vehicle. Figure 4 As shown, the scanning area 43 of the lidar 41 is as follows: Figure 3As shown in the diagonally marked area, when an obstacle (such as a temporarily dropped foreign object) is in the position of... Figure 4 When the scanning area 43 is outside the area shown, the lidar will be unable to detect obstacles. Furthermore, due to the high cost and computational requirements of lidar, most vehicles still opt for the lower-cost, less computationally demanding ultrasonic parking radar 42. However, the ultrasonic parking radar 42 has an inherent drawback of low spatial resolution, typically only used to measure the distance of obstacles relative to the vehicle, and its installation position is relatively high, with a limited scanning area 45. Figure 4 As shown in the diagonal area, ultrasonic parking radar still has a large blind spot and cannot accurately detect the height of obstacles. This application, however, uses a sensor array configured along the lower edge of the bumper to collect the height of target obstacles. Because the lower edge of the bumper is close to the ground level, it reduces the detection blind spot and improves the accuracy of the collected data compared to lidar and ultrasonic parking radar.

[0056] It should be noted that in practical applications, the aforementioned sensor array is used to measure the height of obstacles and the ground clearance of the lower edge of the bumper. To pre-collect and measure obstacle heights, and to avoid insufficient reaction time leading to collisions due to excessively close measurement distances when there is a risk of collision with the lower edge of the bumper, the multiple height sensors in the array can be set to different sampling ranges. For example, refer to... Figure 5 The schematic diagram of the sensor array shown includes a height sensor 52 positioned at a first angle along the lower edge 51 of the bumper, and a height sensor 53 positioned at a second angle along the lower edge 51 of the bumper. Figure 5 It is known that the height sensor 52 is used to measure the ground clearance h1 between the lower edge of the bumper and the driving plane, and the height sensor 53 is used to measure the height h2 of the obstacle. Furthermore, in order to cover the measurement of the height of obstacles at various distances within the identification range from the vehicle's driving direction to the lower edge of the bumper perpendicular to the driving plane, the height sensor 53 can be a sensor with a large measurement range. Alternatively, other height sensors in the sensor array used for measuring obstacle height can be set at different angles to ensure that the measurement range of each height sensor covers the potential identification range.

[0057] It should be noted that, in practical applications, the aforementioned vehicle body state parameters can be parameters characterizing the vehicle's attitude at the current moment. These parameters can be directly collected by the vehicle's state sensors, or collected via a bus or controller connected to the state sensors. Since the vehicle's state affects the bumper's ground clearance—for example, a fully loaded vehicle will reduce the bumper's ground clearance—this application configures the collection of current vehicle body state parameters for subsequent undercarriage warnings. This ensures the warning results match the vehicle's actual attitude, improving the accuracy of subsequent undercarriage warnings.

[0058] It should be noted that in practical applications, the aforementioned driving plane elevation data can be the elevation data of the driving plane at the vehicle's current position and within a preset distance from the vehicle's current position in the direction of travel. This data can be read through the in-vehicle navigation system or navigation software in a mobile device connected to the vehicle. Since the road surface is not a theoretically ideal level, elevation changes caused by factors such as uphill, downhill, road depressions, and bumps directly affect the accuracy of the bumper's ground clearance calculation. Therefore, this application obtains the aforementioned driving plane elevation data through configuration, enabling dynamic acquisition of the actual elevation data of the driving road segment. This improves the accuracy of the subsequent calculation of the bumper's ground clearance at the current moment, thereby improving the final accuracy of the bottoming-out warning.

[0059] S102. Based on the preset 3D model of the bumper, vehicle body state parameters, and driving plane elevation data, calculate the ground clearance of the lower edge of the bumper at the current moment.

[0060] It should be noted that, in practical applications, the aforementioned preset 3D bumper model can be a spatial model of the bumper constructed using drafting tools in the vehicle's spatial coordinate system. This model is composed of the coordinates of various structural points representing the outer surface of the bumper in the vehicle's spatial coordinate system. Since ground clearance can essentially be abstracted as the shortest distance between each position on the lower edge of the bumper's outer surface and the form plane, this application, by constructing the aforementioned preset 3D bumper model, abstracts the bumper into coordinate points in the vehicle's spatial coordinate system, thereby facilitating the accurate calculation of subsequent ground clearance.

[0061] It should be noted that, in practical applications, the ground clearance of the lower edge of the bumper at the current moment can be the shortest distance between the lower edge of the bumper and the driving plane at various points. Since the aforementioned vehicle body state parameters and driving plane elevation data are dynamically collected at the current moment, this application, by configuring a preset 3D bumper model, vehicle body state parameters, and driving plane elevation data, achieves dynamic and accurate calculation of the actual ground clearance of the lowermost edge of the bumper at the current moment, thus improving the accuracy of subsequent bottoming-out warnings.

[0062] S103. Calculate the difference between the ground clearance and the height of the target obstacle. Based on the comparison between the difference and the preset risk distance range, determine the collision risk level and execute the preset risk warning action corresponding to the collision risk level.

[0063] It should be noted that, in practical application scenarios, the schematic diagram of a bottoming-out accident detection scenario is as follows: Figure 6 As shown. By Figure 6As can be seen, since both the ground clearance h1 and the target obstacle height h2 are measured based on the driving plane, this application can obtain the distance between the upper surface of the target obstacle and the lower edge of the bumper at the current moment by configuring and calculating the difference h3 between the ground clearance h1 and the target obstacle height h2.

[0064] In one possible implementation, the above difference can be negative.

[0065] It should be noted that the aforementioned preset risk distance range can be a set of distance values ​​between the obstacle and the lower edge of the bumper obtained through calibration tests. The aforementioned collision risk level can be obtained through calibration tests, considering road conditions and vehicle status, representing the degree of risk of bottoming out accidents corresponding to different distances. In real-world applications, the ground clearance of the lower edge of the bumper fluctuates due to factors such as terrain, speed, and vehicle angle. If this fluctuation causes the ground clearance to be less than the height of the target obstacle (e.g., a negative difference), the obstacle will collide or scrape against the lower edge of the bumper as the vehicle approaches and passes it, resulting in a bottoming out accident. However, if the difference between the ground clearance and the height of the target obstacle is an angle, even with the aforementioned fluctuation, it will not cause a collision or scrape between the obstacle and the lower edge of the bumper. Therefore, this application determines the collision risk level by configuring the comparison results based on the difference and the preset risk distance range. Compared with the prior art, which only identifies whether a collision occurs based on the existence of an obstacle and its distance from the vehicle, this application achieves accurate detection of different degrees of collision risk between the target obstacle and the bumper, and reduces the risk of false alarms.

[0066] It should be noted that, in practical applications, the aforementioned preset risk warning actions can be warning actions set for different risk levels, including but not limited to: voice alarms, photoelectric alarms, active speed adjustment, and active avoidance. This application configures and executes preset risk warning actions corresponding to the collision risk level, thereby passively or actively intervening in the vehicle's state, further reducing the risk of bottoming-out accidents and improving vehicle driving safety.

[0067] This application utilizes a longitudinal sensor array positioned at the bottom edge of the bumper to collect the height of target obstacles at the current moment. This enables the acquisition of the height of obstacles with potential collision risks. By placing the longitudinal sensor array at the bottom edge of the bumper, the bumper shields the sensor array, avoiding the influence of the external environment on the sensor sampling accuracy and further improving the accuracy of subsequent detection. Furthermore, by configuring a preset 3D model of the bumper, vehicle body state parameters, and driving plane elevation data, the application dynamically and accurately calculates the ground clearance at the bottom edge of the bumper at the current moment. Subsequently, by configuring the calculation of the difference between the ground clearance and the height of the target obstacle, and comparing the difference with a preset risk distance range, the application determines the collision risk level, achieving accurate detection of different degrees of collision risk between the target obstacle and the bumper, reducing the risk of false alarms. Finally, by configuring the execution of preset risk warning actions corresponding to the collision risk level, the application achieves differentiated warning intervention for different collision risks, improving vehicle driving safety. Therefore, this application significantly improves the accuracy of vehicle bottoming-out warnings and vehicle driving safety.

[0068] In one possible implementation, based on a preset 3D model of the bumper, vehicle body state parameters, and driving plane elevation data, the ground clearance of the lower edge of the bumper at the current moment is calculated, including:

[0069] Based on the vehicle body state parameters, the preset 3D model of the bumper is mapped from the vehicle space coordinate system to the world coordinate system;

[0070] Based on the driving plane elevation data, a ground elevation interpolation function is constructed, and the ground clearance is calculated using the ground elevation interpolation function based on a preset 3D bumper model in the world coordinate system.

[0071] It should be noted that in practical applications, the aforementioned planar elevation data represents the coordinates of points on the driving plane in the world coordinate system, while the preset 3D model of the bumper includes the coordinates of points on the bumper's surface in the vehicle's spatial coordinate system. Because these are in different spatial coordinate systems, ground clearance cannot be directly calculated. Furthermore, the vehicle's position can change the angle of the bumper relative to the driving plane; for example, due to… Figure 7 As shown in the schematic diagram of a vehicle body state, when the vehicle rolls due to a depression in the driving plane, it causes the bumper to form an angle with the driving plane, which in turn affects the height coordinates of various positions along the lower edge of the bumper in the world coordinate system. Figure 7The height coordinates of points on the bumper (h4 and h5) show significant differences, rather than being uniformly distributed in the vehicle space coordinate system (in the vehicle space coordinate system, the vehicle body is parallel to the driving plane, and the height coordinates of points on the lower edge of the bumper intersecting the driving plane are uniformly distributed). Therefore, this application maps a preset 3D bumper model from the vehicle space coordinate system to the world coordinate system based on vehicle body state parameters. This allows the coordinates of points in the preset 3D bumper model mapped to the world coordinate system to be corrected using the vehicle body state parameters. This ensures that the preset 3D bumper model mapped to the world coordinate system accurately represents the true spatial state of the bumper at the current moment, thereby improving the accuracy of the final ground clearance calculation.

[0072] It should be noted that, in practical applications, the aforementioned ground elevation difference function is used to convert discrete driving plane elevation data into continuous data and to calculate ground clearance. Since the driving plane elevation data is a set of discrete data points on the driving plane in the world coordinate system, it cannot be guaranteed that there exists a corresponding elevation point perpendicular to any point on the lower edge of the bumper. This makes it impossible to directly pre-calculate the elevation of any point on the 3D bumper model based on the driving plane elevation data. Therefore, this application configures a ground elevation interpolation function based on the driving plane elevation data, thereby using the ground elevation difference function to convert the discrete driving plane elevation data into continuous elevation data. This ensures that any point on the pre-designed 3D bumper model in the world coordinate system has a corresponding driving plane elevation data point in its vertical direction. Furthermore, by configuring and utilizing the ground elevation interpolation function based on the pre-designed 3D bumper model in the world coordinate system, the ground clearance of the pre-designed 3D bumper model can be accurately calculated.

[0073] In one possible implementation, the aforementioned ground elevation difference function can output the elevation value corresponding to any coordinate point within the domain (driving plane).

[0074] In one possible implementation, due to the limited backup computing power of the onboard processor, if the driving plane elevation data contains a large number of discrete elevation points, calculating the ground clearance based on all discrete elevation points one by one carries the risk of missing the corresponding elevation point perpendicular to any point on the lower edge of the bumper. Furthermore, there is a risk that the onboard processor's computing power may be insufficient due to the high computational requirements, leading to calculation failure. Therefore, this application configures a ground elevation interpolation function based on the driving plane elevation data, thereby enabling accurate ground clearance calculations based on only a subset of discrete elevation points. This ensures the accuracy of the ground clearance calculation while reducing the computational power required by the onboard processor, thus improving the general applicability of the solution.

[0075] Furthermore, since the aforementioned ground elevation difference function can accurately calculate ground clearance without relying on a large number of discrete elevation points, it is also unnecessary to obtain high-precision driving plane elevation data, thus reducing the cost of use.

[0076] Furthermore, under extremely harsh external environmental conditions, the obtained driving plane elevation data is prone to the risk of missing discrete elevation points. If a method of calculating ground clearance based on all discrete elevation points is used, the accuracy of the ground clearance calculation may decrease due to the missing discrete elevation points. Therefore, this application configures a ground elevation interpolation function based on the driving plane elevation data, thereby outputting accurate driving plane elevation values ​​even when data points are missing, thus ensuring the accuracy of the ground clearance calculation and improving the environmental robustness of this application during execution.

[0077] In one possible implementation, the vehicle body state parameters include: vehicle attitude angles, vehicle load, basic vehicle parameters, and suspension travel. Based on these vehicle body state parameters, a pre-defined 3D model of the bumper is mapped from the vehicle space coordinate system to the world coordinate system, including:

[0078] The vehicle attitude angle is corrected based on the vehicle load, basic vehicle parameters, and suspension travel.

[0079] Construct a homogeneous transformation matrix from the vehicle space coordinate system to the world coordinate system based on the corrected vehicle attitude angle;

[0080] Based on the homogeneous transformation matrix, the discrete points on the lower edge surface of the pre-set 3D model of the bumper in the vehicle spatial coordinate system are mapped to the world coordinate system.

[0081] It should be noted that the aforementioned vehicle attitude angles are parameters describing the vehicle's attitude or orientation in three-dimensional space relative to a reference coordinate system (usually the world coordinate system). They typically consist of three independent rotation angles, representing the vehicle's rotation about its own coordinate system's three axes. Specifically, the roll angle describes the vehicle's rotation about its longitudinal axis, reflecting the degree of left-right tilt; the pitch angle describes the vehicle's rotation about its lateral axis, reflecting the degree of pitching up or down; and the yaw angle describes the vehicle's rotation about its vertical axis, reflecting the vehicle's steering or heading. These angles can be acquired in real time using various methods, such as an inertial measurement unit (IMU) combined with attitude calculation algorithms or a high-precision Global Navigation Satellite System (GNSS) receiver.

[0082] It should be noted that in practical applications, existing vehicle attitude angles are mostly collected and output by the vehicle's Inertial Measurement Unit (IMU). Since the IMU obtains the vehicle attitude angles by integrating the collected vehicle angular velocity and linear acceleration, the IMU outputs only represent the vehicle's inertial attitude, not its actual driving attitude relative to the driving plane. Specifically, the vehicle body and wheels are connected by an elastic suspension, meaning the vehicle body is not an absolutely rigid body directly in contact with the driving plane. Compression or extension of the elastic suspension directly changes the vehicle's attitude and ground clearance relative to the ground. However, the IMU cannot sense these changes in the vehicle attitude angles caused by the compression or extension of the elastic suspension. If the obtained vehicle attitude angles are directly used to construct the subsequent homogeneous transformation matrix, the discrete points mapped by the homogeneous transformation matrix will not accurately represent the current spatial state of the bumper, thus affecting the accuracy of the subsequent ground clearance calculation. For example, when the vehicle is empty and parked on a level surface, the pitch and roll angles measured by the IMU are both 0°, which meets the design specifications. However, when the vehicle is fully loaded with 5 people and the trunk is full, assuming the total load increases by 400kg, the front suspension is compressed by 5cm and the rear suspension by 3cm, causing the front of the vehicle to tilt downwards. At this point, the vehicle body itself remains level, and the pitch angle measured by the IMU is still 0°. However, the actual pitch angle of the vehicle body relative to the ground has deviated by 1.15° (due to a 2cm difference in front and rear suspension compression, a 2.8m wheelbase, and an arctan(0.02) value). (m / 2.8m)≈0.41°, with actual deviations generally between 0.5° and 2° under full load). Furthermore, when the vehicle goes over speed bumps, one wheel hits the shoulder, or the road surface is continuously bumpy, the elastic suspension will experience high-frequency compression / stretching at the millisecond level, and the vehicle body will experience real-time tilt or pitch relative to the ground. However, the attitude calculation of the IMU has an integral delay of 100-200ms and cannot distinguish between the attitude changes caused by suspension deformation and the attitude changes caused by rigid body rotation. The deviation between the output original attitude angle and the actual attitude angle generally exceeds 1°-3°.

[0083] It should be noted that when the accuracy of the vehicle attitude angle obtained at the current moment is reduced due to the compression or extension of the elastic suspension, this defect will be further amplified due to the leverage effect. Specifically, the vehicle bumper is usually located at the edge of the vehicle body. Since there is generally a certain distance between the bumper and the vehicle axle, this constitutes a lever arm. When the actual vehicle attitude angle differs from the vehicle attitude angle measured by the IMU unit due to the compression or extension of the elastic suspension, this difference will be further amplified by the aforementioned lever arm. This will lead to a further amplification of the difference between the actual bumper attitude angle and the vehicle attitude angle collected by the IMU unit compared to the difference between the vehicle attitude angle collected by the IMU unit and the actual vehicle attitude angle. If the subsequent homogeneous transformation matrix is ​​constructed directly based on the obtained vehicle attitude angle, the discrete points mapped by the homogeneous transformation matrix will not be able to accurately represent the actual spatial state of the bumper at the current moment, thus affecting the accuracy of the subsequent ground clearance calculation.

[0084] In summary, considering the inherent defects of the vehicle attitude angle obtained at the current moment, this application improves the accuracy of the subsequent homogeneous transformation matrix construction by configuring the vehicle load, basic vehicle parameters, and suspension travel. This improves the accuracy of the representation of the current bumper spatial state by each discrete point mapped to the world coordinate system based on the homogeneous transformation matrix.

[0085] It should be noted that in practical applications, due to the different construction benchmarks of the vehicle spatial coordinate system and the world coordinate system, it is impossible to directly perform discrete point calculations based on the preset 3D bumper model and driving plane elevation data in different coordinate systems. Furthermore, since the preset 3D bumper model in the vehicle spatial coordinate system represents the spatial position of the bumper in a horizontal driving plane and in a stationary state, it cannot accurately represent the actual posture of the vehicle body at the current moment. Therefore, this application constructs a homogeneous transformation matrix from the vehicle spatial coordinate system to the world coordinate system based on the modified vehicle attitude angle. Based on the homogeneous transformation matrix, it maps each discrete point on the lower edge surface of the preset bumper 3D model in the vehicle spatial coordinate system to the world coordinate system. This unifies the coordinate system reference of each discrete point of the preset bumper 3D model with the discrete elevation points in the driving plane elevation data. At the same time, it uses the modified vehicle attitude angle to adjust the position of each discrete point of the preset bumper 3D model in the world coordinate system. This ensures that the preset bumper 3D model accurately represents the attitude and spatial position of the bumper at the current moment after being mapped to the world coordinate system, thereby improving the accuracy of subsequent ground clearance calculation and the final accuracy of bottoming-out warning.

[0086] In one possible implementation, the aforementioned vehicle fundamental parameters include suspension stiffness, track width, and wheelbase. Based on the vehicle load, vehicle fundamental parameters, and suspension travel, the vehicle attitude angles are corrected, including:

[0087] The static load compression of the suspension is obtained based on the vehicle load and suspension stiffness, and the suspension travel is updated using the static load compression.

[0088] Calculate the roll angle correction based on the track width and the updated suspension travel; calculate the pitch angle correction based on the wheelbase and the updated suspension travel.

[0089] Based on the roll angle correction and pitch angle correction, the roll angle and pitch angle in the vehicle attitude angle are superimposed and corrected respectively.

[0090] It should be noted that in practical applications, the vehicle attitude angles measured by existing IMU units are calculated based on the suspension travel calibrated under unloaded conditions. However, when the vehicle load changes, the suspension travel deviates from the calibrated value, leading to a discrepancy between the vehicle attitude angles measured by the IMU unit and the actual vehicle attitude angles. Therefore, this application configures the system to obtain the suspension static compression based on the vehicle load and suspension stiffness, and uses this static compression to update the suspension travel. This allows the updated suspension travel to adapt to the actual suspension extension and contraction state of the current vehicle, thereby improving the accuracy of subsequent corrections to the vehicle attitude angles.

[0091] It should be noted that, in practical applications, there are multiple implementation methods for obtaining the suspension static compression based on vehicle load and suspension stiffness, and then updating the suspension travel using the suspension static compression. Two examples are provided here:

[0092] Example 1: Given the limited computing power of the onboard processor, the static load compression of the suspension for different vehicle models under different vehicle load conditions can be pre-calibrated, and the calibrated static load compression, suspension stiffness (differentiating between different vehicle models), and vehicle load can be stored in a data table. Then, during actual use, the static load compression of the suspension at the current moment is obtained by looking up the table based on the vehicle load and suspension stiffness. The suspension travel is then updated by superimposing the static load compression with the currently collected suspension travel value. The static load compression can be either positive or negative.

[0093] Example 2: When the onboard processor has sufficient computing power, the above-mentioned suspension static load compression... The calculation formula is: Where m is the vehicle load, g is the gravitational acceleration, and K is the suspension stiffness. Then, the suspension travel is updated by superimposing the static load compression of the suspension with the suspension travel collected at the current moment.

[0094] In one possible implementation, since different wheels are in different positions during driving, the suspension travel corresponding to each wheel will vary. Therefore, to further improve the accuracy of updating the suspension travel, the above-mentioned method of superimposing the suspension static load compression with the suspension travel collected at the current moment can be as follows: the quotient of the suspension static load compression and the total number of wheels is determined as the independent suspension static load compression of each wheel; the independent suspension static load compression and suspension travel corresponding to the same wheel are superimposed to obtain the updated suspension travel corresponding to that wheel.

[0095] It should be noted that in practical applications, the vehicle's roll angle is the angle between the vehicle's transverse axis (axle) and the horizontal line (a straight line in the driving plane perpendicular to the projection of the vehicle's front and rear center lines), and it is affected by the track width and the suspension travel on both sides of the vehicle body. Therefore, this application achieves accurate calculation of the actual roll angle correction at the current moment by configuring the suspension travel based on the track width and the updated suspension travel.

[0096] It should be noted that, in practical applications, the above implementation method for calculating the roll angle correction based on the wheelbase and the updated suspension travel can be:

[0097] The above roll angle correction amount The calculation formula is: , of which S l It is the average suspension travel on the left front and rear sides, S r B is the average suspension travel on the front and rear of the right side, and B is the track width.

[0098] It should be noted that in practical applications, the vehicle's pitch angle is the angle between the vehicle's longitudinal axis (center line of the front and rear axles) and the driving plane, and it is affected by the wheelbase and the travel of the front and rear suspensions. Therefore, this application achieves accurate calculation of the actual pitch angle correction at the current moment by configuring the suspension travel based on the wheelbase and the updated suspension travel.

[0099] It should be noted that, in practical applications, the above implementation method for calculating the pitch angle correction based on the wheelbase and the updated suspension travel can be:

[0100] The above pitch angle correction amount The calculation formula is: , of which S f It is the average suspension travel on the left and right sides of the front, S b It is the average suspension travel on the left and right sides of the rear, and L is the wheelbase.

[0101] In one possible implementation, the vehicle attitude angles include roll angle, pitch angle, and yaw angle. Based on the corrected vehicle attitude angles, a homogeneous transformation matrix from the vehicle space coordinate system to the world coordinate system is constructed, including:

[0102] Construct rotation matrices for roll angle, pitch angle and yaw angle respectively, and determine the product of each rotation matrix as the initial homogeneous transformation matrix;

[0103] The origin coordinates of the world coordinate system are used as a column of data. The initial homogeneous transformation matrix is ​​augmented based on the column data to obtain the homogeneous transformation matrix.

[0104] It should be noted that in practical applications, the initial homogeneous transformation matrix is ​​a 3×3 matrix, while the world coordinate system is a three-axis coordinate system. Therefore, when integrating the origin coordinates of the world coordinate system into the initial homogeneous transformation matrix, 1 can be used to integrate them with the origin coordinates to obtain a 4×4 homogeneous transformation matrix. This application achieves a unified reference between the vehicle space coordinate system and the world coordinate system by configuring the integration of the initial homogeneous transformation matrix and the origin coordinates. This improves the accuracy of representing the true position and state of the bumper at the current moment after mapping the preset 3D bumper model to the world coordinate system.

[0105] In one possible implementation, a ground elevation interpolation function is constructed based on driving plane elevation data, and the ground clearance is calculated using the ground elevation interpolation function based on a preset 3D bumper model in the world coordinate system, including:

[0106] Map the driving plane elevation data to a set of discrete ground points in the world coordinate system;

[0107] A ground elevation interpolation function is constructed based on a set of discrete ground points using a preset interpolation algorithm. The input of the ground elevation interpolation function is the coordinates of the discrete points in the world coordinate system, and the output of the ground elevation interpolation function is the initial ground clearance corresponding to the discrete points.

[0108] The minimum value among the initial ground clearances is determined as the ground clearance of the lower edge of the bumper at the current moment.

[0109] It should be noted that, in practical applications, the aforementioned preset interpolation algorithm is a program script used to construct the ground elevation interpolation function and assist in selecting the minimum value among the initial ground clearances. The specific types of the aforementioned ground elevation interpolation function can be various, including but not limited to: bilinear interpolation (BI) function, cubic spline interpolation (CSI) function, ordinary kriging interpolation (OK) function, and inverse distance weighted interpolation (IDW) function. This application does not impose excessive limitations or elaborate on the specific construction process and type of the aforementioned preset interpolation algorithm and ground elevation interpolation function.

[0110] In one possible implementation, the minimum value H among the aforementioned initial ground clearances is... min The following formula can be used for filtering: Where Q is the set of coordinate points in the world coordinate system, and i is the i-th coordinate point on the lower edge surface of the bumper in Q. It is the height coordinate of the i-th point on the lower edge of the bumper in the world coordinate system. and These are the x and y coordinates of the i-th point on the lower edge of the bumper in the world coordinate system. It is the elevation value of the driving plane corresponding to the i-th coordinate point on the lower edge of the bumper in the world coordinate system. The initial ground clearance corresponding to the i-th coordinate point.

[0111] In one possible implementation, the collision risk level includes: a high collision risk level where the difference is less than the lower limit of a preset risk distance interval; and, if the collision risk level is high, executing a preset risk warning action corresponding to the collision risk level, including:

[0112] Collect the vehicle speed at the current moment, as well as the distance between the vehicle and the target obstacle at the current moment;

[0113] When the distance is less than the safe distance threshold and the vehicle speed is less than the preset safe speed threshold, a braking trigger signal is sent to the braking system.

[0114] When the distance between vehicles is not less than the safety distance threshold and / or the vehicle speed is not less than the preset safety speed threshold, a deceleration trigger signal is sent to the adaptive cycle control system.

[0115] It should be noted that, in practical applications, the distance between the vehicle and the target obstacle at the current moment can be obtained through the vehicle's LiDAR, millimeter-wave radar, or image recognition module. This application does not impose further limitations or elaborate on the method of obtaining the aforementioned distance.

[0116] It should be noted that, in practical application scenarios, the above-mentioned collision risk levels may also include low collision risk levels that do not trigger active vehicle status control. These low collision risk levels may be triggered when the distance is less than a preset safe distance threshold or the vehicle speed is less than a preset safe speed threshold.

[0117] It should be noted that in practical applications, there can be multiple preset risk warning actions corresponding to the aforementioned low collision risk level. Two examples are provided here:

[0118] Example 1: When the collision risk level is low, send an icon prompt trigger signal to the display device to make the display device display a collision warning icon;

[0119] Example 2: When the collision risk level is low, a prompt signal is sent to the human-computer interaction device so that the human-computer interaction device outputs a voice alarm signal and a head-up display (HUD) text prompt signal.

[0120] To facilitate understanding of the vehicle bottoming-out warning method provided in the first aspect of this application, an example of a possible implementation of this application is described below:

[0121] Imagine a vehicle is about to go over a speed bump. At this moment, the vehicle's undercarriage warning system activates.

[0122] First, at any given moment, a sensor array (e.g., multiple ultrasonic sensors) positioned along the lower edge of the vehicle's bumper continuously collects data on the top height of the speed bump to determine the height of the target obstacle. Simultaneously, sensors inside the vehicle (e.g., IMU, load sensors, suspension displacement sensors) acquire real-time vehicle attitude angles, vehicle load, suspension travel, and other vehicle status parameters. Furthermore, the system utilizes the in-vehicle navigation system combined with high-precision map data to obtain the vehicle's current driving plane elevation data, which describes the undulations of the ground around the speed bump.

[0123] Next, after receiving this data, the controller begins calculating the ground clearance of the lower edge of the bumper. The controller internally stores a preset 3D model of the vehicle's bumper. First, using the acquired vehicle state parameters, the controller maps this preset 3D model of the bumper from the vehicle's own coordinate system to the world coordinate system, considering the influence of the vehicle's real-time attitude and load on the bumper's position. Then, based on the acquired elevation data of the driving plane, the controller constructs an elevation model of the ground in front of the vehicle. By comparing the vertical distance between the lowest surface of the bumper's 3D model in the world coordinate system and the ground elevation model, the controller calculates the ground clearance of the lower edge of the bumper at the current moment.

[0124] The controller then compares the calculated ground clearance with the target obstacle height acquired by the sensor array, calculating the difference between the two. For example, if the ground clearance is 150mm and the target obstacle height is 100mm, the difference is 50mm. The controller compares this 50mm difference with a preset risk distance range. Assume the preset risk distance range is defined as follows: a difference greater than 40mm indicates low risk, 20mm to 40mm indicates medium risk, and less than 20mm indicates high risk. In this example, the 50mm difference falls within the low-risk range, therefore the system determines the current collision risk level to be low.

[0125] Finally, based on the determined low collision risk level, the system executes the corresponding preset risk warning actions. In this case, the system may only display a green "Safe to Pass" message on the vehicle's dashboard, or it may not execute any active warning actions to avoid unnecessary interference. If, at other times, such as when the vehicle is passing a higher or sharper obstacle at high speed, the calculated difference falls into the medium or high risk range, the system will issue audible and visual alarms according to the corresponding risk level, and may even send a braking trigger signal to the braking system or a deceleration trigger signal to the adaptive cruise control system to actively reduce the vehicle speed or bring it to a stop, thereby avoiding a vehicle bottoming-out accident.

[0126] Through the above process, this method can assess the collision risk between the vehicle bumper and obstacles in real time and accurately, and take corresponding early warning measures according to the risk level, thereby improving the safety of vehicle driving.

[0127] In one possible implementation, the method for determining the collision risk level based on the comparison between the difference and a preset risk distance interval can be as follows: when the difference is within the preset risk distance interval, the collision risk level is output as low risk. When the difference is less than the lower limit of the preset risk distance interval, the collision risk level is output as high risk. When the difference is greater than the upper limit of the preset risk distance interval, the collision risk level is output as no risk.

[0128] To facilitate understanding of the vehicle bottoming-out warning method provided by the first aspect and any implementation thereof of this application, an explanation is provided here in conjunction with one possible implementation of this application:

[0129] like Figure 8 The diagram shows a flowchart of a vehicle bottoming-out warning method. The specific operation steps are as follows:

[0130] Step S801: The vehicle is powered on and started. This triggers step S802.

[0131] Step S802: Obtain the current target obstacle height collected by the sensor array, as well as the current vehicle body state parameters and driving plane elevation data. Then trigger step S803.

[0132] Step S803: Based on the vehicle load, basic vehicle parameters, and suspension travel in the vehicle state parameters, the vehicle attitude angle in the vehicle state parameters is corrected. Step S804 is then triggered.

[0133] Step S804: Construct a homogeneous transformation matrix from the vehicle space coordinate system to the world coordinate system based on the corrected vehicle attitude angles. Then, step S805 is triggered.

[0134] Step S805: Based on the homogeneous transformation matrix, map each discrete point on the lower edge surface of the pre-set bumper 3D model in the vehicle space coordinate system to the world coordinate system. Then, step S806 is triggered.

[0135] Step S806: Map the driving plane elevation data to a set of discrete ground points in the world coordinate system. Then trigger step S807.

[0136] Step S807: Construct the ground elevation interpolation function based on the set of discrete ground points using a preset interpolation algorithm. This triggers step S808.

[0137] Step S808: Determine the minimum value among the initial ground clearances as the ground clearance of the lower edge of the bumper at the current moment. Then trigger step S809.

[0138] Step S809: Calculate the difference between the ground clearance and the height of the target obstacle. Then trigger step S810.

[0139] Step S810: Determine whether the difference is greater than the upper limit of the preset risk interval. If yes, trigger step S802; otherwise, trigger step S811.

[0140] Step S811: Determine whether the difference is less than the lower limit of the preset risk interval. If yes, trigger step S812; otherwise, trigger step S813.

[0141] Step S812: Collect the current vehicle speed and the distance between the vehicle and the target obstacle at the current moment. Then trigger step S814.

[0142] Step S813: Execute the preset risk warning action corresponding to the low-risk level. This triggers step S802.

[0143] Step S814: Determine whether the distance and vehicle speed simultaneously meet the conditions that the distance is less than the safe distance threshold and the vehicle speed is less than the preset safe vehicle speed threshold. If yes, then trigger step S815; otherwise, trigger step S816.

[0144] Step S815: Send a brake trigger signal to the braking system. This triggers step S802.

[0145] Step S816: Send a deceleration trigger signal to the adaptive cycle control system. This triggers step S802.

[0146] It should be noted that, in practical application scenarios, steps S801 and S802 are as follows: Figure 1 In the embodiment of step S801 shown, steps S803 to S808 are as follows: Figure 1 In the embodiment of step S102 shown, steps S809 to S816 are as follows: Figure 1 An embodiment of step S103 shown.

[0147] A second aspect of this application provides a vehicle bottoming-out warning system, comprising:

[0148] A sensor array, and a controller for performing a vehicle bottoming warning method as described in the first aspect and any implementation thereof, wherein the sensor array is disposed at the lower edge of the bumper;

[0149] The sensor array communicates with the controller.

[0150] It should be noted that, in practical application scenarios, the vehicle bottoming-out warning system provided in the second aspect of this application, by configuring a sensor array along the lower edge of the bumper, reduces the impact of the external environment on the sensor measurement accuracy compared to existing technologies that use vehicle perimeter sensors for bottoming-out warning. Specifically, by using the bumper to obscure the sensor array, it is difficult for external objects to directly cover the sampling port of the sensor array, thereby reducing the impact of the external environment on the sensor measurement accuracy. Furthermore, by configuring the sensor array along the lower edge of the bumper to collect the height of the target obstacle, since the lower edge of the bumper is close to the ground height, the detection blind spot is reduced compared to lidar and ultrasonic parking radar, improving the accuracy of the collected data. Finally, by configuring the sensor array to communicate with a controller, and the controller being used to execute the vehicle bottoming-out warning method as described in the first aspect and any implementation thereof, this not only achieves dynamic and accurate calculation of the ground clearance of the lowest edge of the bumper at the current moment, but also achieves accurate detection of different degrees of collision risk between the target obstacle and the bumper, reducing the risk of false alarms, and improving vehicle driving safety by providing differentiated warning interventions for different collision risks. It is evident that this application improves the accuracy of vehicle bottoming-out warning and vehicle driving safety.

[0151] It should be noted that in practical applications, there are multiple ways for the above-mentioned sensor array and controller to communicate and connect. Two examples are provided here:

[0152] Example 1: The aforementioned sensor array is communicatively connected to a controller used to execute the vehicle bottoming warning method of the first aspect of this application and any implementation thereof via the vehicle's Controller Area Network (CAN bus).

[0153] Example 2: The sensor array described above is connected to the controller via a wireless communication device. The types of wireless communication devices include, but are not limited to: UWB Ultra Wideband Module (UWB Module), Sub-1GHz RF Transceiver Module (Sub-1GHz Module), Automotive Ethernet Wireless Bridge (AE Wireless Bridge), etc.

[0154] In one possible implementation, the aforementioned sensor array includes:

[0155] Multiple height sensors are mounted on the vehicle's bumper in a direction perpendicular to the static tire contact surface, with the probe plane of the height sensor flush with the plane of the lower edge of the bumper, and the height sensors are installed at intervals.

[0156] It should be noted that, in practical applications, the aforementioned height measurement sensor may include one or more of laser rangefinders and ultrasonic sensors. Preferably, since ultrasonic sensors can still perform height measurement even when the probe is contaminated with foreign objects, and their height measurement performance for soft targets is better than that of laser rangefinders, the aforementioned sensor array can be configured using a combination of multiple laser sensors and multiple ultrasonic sensors, thereby improving the operational reliability of the height measurement sensor.

[0157] It should be noted that in practical applications, the aforementioned multiple height sensors can be installed at different angles to expand the detection range of the sensor array.

[0158] It should be noted that in practical applications, the aforementioned sensor array can be movably installed in a preset slot on the lower edge of the bumper by snap-fit, or it can be fixed to the lower edge of the bumper by bolts.

[0159] It should be noted that, in practical applications, the controller can also communicate with the vehicle's IMU unit and other sensors via the CAN bus to obtain the vehicle's current status parameters and driving plane elevation data.

[0160] A schematic diagram of the structure of a controller for a vehicle bottoming-out warning system provided in the second aspect of this application is shown below. Figure 9 As shown. The controller in the embodiments of this application may include, but is not limited to, fixed terminals such as Electronic Control Unit (ECU), Vehicle Control Unit (VCU), Domain Control Unit (DCU), etc. Figure 9 The controller shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0161] like Figure 9As shown, the controller may include a processing device (e.g., a central processing unit, a graphics processing unit, etc.) 901, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 902 or a program loaded from a storage device 908 into a random access memory (RAM) 903. When the controller is powered on, the RAM 903 also stores various programs and data required for controller operation. The processing device 901, ROM 902, and RAM 903 are interconnected via a bus 904. An input / output (I / O) interface 905 is also connected to the bus 904.

[0162] Typically, the following devices can be connected to I / O interface 905: input devices 906 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 907 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 908 including, for example, memory cards, hard drives, etc.; and communication devices 909. Communication device 909 allows the controller to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 9 A controller with various devices is shown; however, it should be understood that implementation or possession of all the devices shown is not required. More or fewer devices may be implemented alternatively.

[0163] A third aspect of this application provides a vehicle, including a vehicle bottoming-out warning system as described in the second aspect of this application and any implementation thereof.

[0164] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the device embodiment drawings provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0165] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0166] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0167] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A method for vehicle bottoming-out warning, characterized in that, A controller for a vehicle bottoming-out warning system, the vehicle bottoming-out warning system further comprising a sensor array disposed along the lower edge of the bumper for measuring the ground clearance of the lower edge of the bumper, the vehicle bottoming-out warning method comprising: Obtain the height of the target obstacle collected by the sensor array at the current moment, as well as the vehicle body state parameters and driving plane elevation data at the current moment; Based on the preset 3D model of the bumper, the vehicle body state parameters, and the driving plane elevation data, the ground clearance of the lower edge of the bumper at the current moment is calculated. Calculate the difference between the ground clearance and the height of the target obstacle. Based on the comparison between the difference and the preset risk distance range, determine the collision risk level and execute the preset risk warning action corresponding to the collision risk level.

2. The vehicle bottoming-out warning method according to claim 1, characterized in that, The calculation of the ground clearance of the lower edge of the bumper at the current moment, based on the preset 3D model of the bumper, the vehicle body state parameters, and the driving plane elevation data, includes: Based on the vehicle body state parameters, the preset three-dimensional model of the bumper is mapped from the vehicle space coordinate system to the world coordinate system; Based on the driving plane elevation data, a ground elevation interpolation function is constructed, and the ground clearance is calculated using the ground elevation interpolation function based on the preset three-dimensional model of the bumper in the world coordinate system.

3. The vehicle bottoming-out warning method according to claim 2, characterized in that, The vehicle body state parameters include: vehicle attitude angle, vehicle load, vehicle basic parameters, and suspension travel. Mapping the preset bumper 3D model from the vehicle space coordinate system to the world coordinate system based on these vehicle body state parameters includes: The vehicle attitude angle is corrected based on the vehicle load, the vehicle basic parameters, and the suspension travel. Based on the corrected vehicle attitude angles, construct a homogeneous transformation matrix from the vehicle space coordinate system to the world coordinate system; Based on the homogeneous transformation matrix, each discrete point on the lower edge surface of the pre-set bumper 3D model in the vehicle spatial coordinate system is mapped to the world coordinate system.

4. The vehicle bottoming-out warning method according to claim 3, characterized in that, The vehicle's basic parameters include suspension stiffness, track width, and wheelbase. The correction of the vehicle's attitude angle based on the vehicle's load, the vehicle's basic parameters, and the suspension travel includes: The suspension static compression is obtained based on the vehicle load and the suspension stiffness, and the suspension travel is updated using the suspension static compression. Based on the track width and the updated suspension travel, calculate the roll angle correction; based on the wheelbase and the updated suspension travel, calculate the pitch angle correction. Based on the roll angle correction and the pitch angle correction, the roll angle and pitch angle in the vehicle attitude angle are superimposed and corrected respectively.

5. The vehicle bottoming-out warning method according to claim 3, characterized in that, The vehicle attitude angles include roll angle, pitch angle, and yaw angle. The construction of a homogeneous transformation matrix from the vehicle spatial coordinate system to the world coordinate system based on the corrected vehicle attitude angles includes: The rotation matrices for the roll angle, pitch angle and yaw angle are constructed respectively, and the product of the rotation matrices is determined as the initial homogeneous transformation matrix; The origin coordinates of the world coordinate system are used as a column of data. The initial homogeneous transformation matrix is ​​augmented based on the column of data to obtain the homogeneous transformation matrix.

6. The vehicle bottoming-out warning method according to claim 2, characterized in that, The step of constructing a ground elevation interpolation function based on the driving plane elevation data, and using the ground elevation interpolation function to calculate the ground clearance based on the preset bumper 3D model in the world coordinate system, includes: Map the driving plane elevation data to the set of discrete ground points in the world coordinate system; The ground elevation interpolation function is constructed based on the set of discrete ground points using a preset interpolation algorithm. The input of the ground elevation interpolation function is the coordinates of the discrete points in the world coordinate system, and the output of the ground elevation interpolation function is the initial ground clearance corresponding to the discrete points. The minimum value among the initial ground clearances is determined as the ground clearance of the lower edge of the bumper at the current moment.

7. The vehicle bottoming-out warning method according to claim 1, characterized in that, The collision risk level includes: a high collision risk level where the difference is less than the lower limit of the preset risk distance range; and when the collision risk level is the high collision risk level, executing the preset risk warning action corresponding to the collision risk level includes: Collect the vehicle speed at the current moment, and the distance between the vehicle and the target obstacle at the current moment; When the distance is less than the safe distance threshold and the vehicle speed is less than the preset safe vehicle speed threshold, a braking trigger signal is sent to the braking system. If the distance is not less than the safe distance threshold and / or the vehicle speed is not less than the preset safe vehicle speed threshold, a deceleration trigger signal is sent to the adaptive cycle control system.

8. A vehicle bottoming-out warning system, characterized in that, include: A sensor array, and a controller for performing the vehicle bottoming warning method as described in any one of claims 1 to 7, wherein the sensor array is disposed at the lower edge of the bumper; The sensor array is communicatively connected to the controller.

9. The vehicle bottoming-out warning system according to claim 8, characterized in that, The sensor array includes: Multiple height sensors are mounted on the vehicle's bumper in a direction perpendicular to the static tire contact surface, with the probe plane of the height sensor being flush with the plane of the lower edge of the bumper, and the height sensors are installed at intervals.

10. A vehicle, characterized in that, include: The vehicle bottoming-out warning system as described in any one of claims 8 and 9.

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