Parking safety vehicle speed calculation method

Abstract

The application provides a parking safety vehicle speed calculation method, comprising: calibrating a vehicle body feature point; determining a current driving scene of the vehicle according to current gear information of the vehicle, finding a corresponding distance interval table and a speed related restriction table based on the current driving scene of the vehicle; finding a corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle body feature point; obtaining speed related restriction data of the current period in the speed related restriction table according to the distance interval number; and calculating the parking safety vehicle speed of the current period based on the parking safety vehicle speed of the last period and the speed related restriction data of the current period. The application adopts different strategies (vehicle speed planning parameters) for different obstacles in different regions of different vehicles, calculates the safety vehicle speed in real time, can optimize the risk introduced by the insufficient obstacle detection accuracy, and enables the target vehicle to drive at a safe and controllable speed when passing through the obstacle and does not appear the situation of sudden braking and stopping.

Description

Technical Field

[0001] This invention relates to the field of automatic parking, and more specifically, to a method for calculating safe parking speed. Background Technology

[0002] After determining the parking path, the automatic parking system needs to ensure that the vehicle travels along that path. This task is typically performed by the vehicle control module. Besides directional requirements, vehicle movement also has speed requirements. Correspondingly, the vehicle control module handles lateral control and longitudinal control. Lateral control primarily addresses directional requirements, while longitudinal control primarily addresses speed requirements. Speed ​​planning based on obstacle distance is a type of speed planning that primarily addresses the smoothness and safety of speed changes when the vehicle approaches or moves away from obstacles while traveling along the parking path.

[0003] Existing parking speed planning methods generally use a combination of constant speed and linear increase / decrease to plan speed. That is, the speed increases and decreases linearly at the beginning and end of parking, while the speed is fixed in the middle of the parking path. This method of speed planning does not have good stability. When obstacles are encountered, it is easy to brake suddenly and stop suddenly without leaving a safe distance, and safety cannot be guaranteed. Summary of the Invention

[0004] To address the issues of speed smoothness and safety in parking trajectory planning near obstacles, according to a first aspect of the present invention, a method for calculating safe parking speed is provided, comprising:

[0005] Calibrate vehicle body feature points;

[0006] Determine the current driving scenario of the vehicle based on the current gear information, and find the corresponding distance interval table and speed-related limit table based on the current driving scenario;

[0007] Based on the distance between the obstacle and the vehicle's feature points, find the corresponding distance interval number in the distance interval table;

[0008] Based on the distance interval number, obtain the speed-related limit data for this period from the speed-related limit table;

[0009] The safe parking speed for the current period is calculated based on the safe parking speed of the previous period and the speed-related limit data for the current period.

[0010] Based on the above technical solution, the present invention can also be improved as follows.

[0011] Optionally, the calibration of vehicle body feature points includes:

[0012] The vehicle coordinate system is established with the center of the rear wheel axle perpendicular to the front of the vehicle as the X-axis and the center of the rear wheel axle perpendicular to the left of the rear wheel axle as the Y-axis.

[0013] Based on a preset clockwise angle as the step size, the vehicle's outer contour points are selected as body feature points; and based on a preset clockwise angle as the step size, the vehicle's outer contour points are selected as body feature points; and multiple body feature points are obtained by equally dividing the vehicle's rear and front axles.

[0014] Obtain the coordinates of all vehicle body feature points in the vehicle coordinate system.

[0015] Optionally, the current driving scenario of the vehicle includes a forward driving scenario and a reverse driving scenario, and also includes:

[0016] For forward and backward scenarios, establish corresponding distance interval tables and speed-related limit tables respectively;

[0017] The distance interval table records the correspondence between the distance range of vehicle feature points in different locations of the vehicle and the distance interval number;

[0018] The speed-related limit table records the correspondence between distance interval numbers and speed-related limit data.

[0019] Optionally, obstacle information near the vehicle can be obtained based on multi-sensor fusion, wherein the multi-sensor includes a visual sensor, an ultrasonic radar sensor, and a lidar sensor.

[0020] Optionally, the step of finding the corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle's feature points includes:

[0021] Calculate the distance between the obstacle and the vehicle feature points in each location area; wherein, each location area includes multiple vehicle feature points, and the minimum distance between the obstacle and the multiple vehicle feature points in each location area is taken as the distance between the obstacle and the vehicle feature points in each location area.

[0022] Based on the distance between the obstacle and the vehicle feature points in each location area, and based on the correspondence between the distance range of the vehicle feature points in each location area and the distance interval number, the corresponding distance interval number in each location area is obtained.

[0023] Use the minimum distance interval number as the distance interval number corresponding to the obstacle.

[0024] Optionally, the obstacles include multiple obstacles, and for any one obstacle, the distance interval number corresponding to that obstacle is obtained;

[0025] Iterate through each obstacle and obtain the distance interval number corresponding to each obstacle;

[0026] The smallest distance interval number among all distance interval numbers corresponding to obstacles is taken as the final distance interval number corresponding to the obstacle.

[0027] Optionally, the speed-related limit data includes reference limit speed, reference limit acceleration, reference limit deceleration, reference limit acceleration rate of change, and reference limit deceleration rate of change. The calculation of the safe parking speed for the current period based on the safe parking speed of the previous period and the speed-related limit data for the current period includes:

[0028] Based on the relationship between the safe parking speed of the previous cycle and the reference speed limit of the current cycle, determine whether the vehicle needs to enter an acceleration or deceleration scenario.

[0029] When a vehicle needs to enter a deceleration scenario, the deceleration for the current cycle is calculated based on the relationship between the deceleration of the previous cycle and the reference limit deceleration for the current cycle.

[0030] When a vehicle needs to enter an acceleration scenario, the acceleration for the current cycle is calculated based on the relationship between the acceleration of the previous cycle and the reference limit acceleration for the current cycle.

[0031] The safe parking speed for the current cycle can be calculated based on the safe parking speed of the previous cycle and the deceleration of the current cycle, or based on the safe parking speed of the previous cycle and the acceleration of the current cycle.

[0032] Optionally, determining whether the vehicle needs to enter an acceleration scenario based on the relationship between the safe parking speed of the previous cycle and the reference speed limit of the current cycle includes:

[0033] When the safe parking speed of the previous cycle is greater than the reference speed limit of the current cycle, the vehicle needs to enter the deceleration scenario.

[0034] When the safe parking speed of the previous cycle is less than the reference speed limit of the current cycle, the vehicle needs to enter the acceleration scenario;

[0035] If the safe parking speed of the previous cycle equals the reference speed limit of the current cycle, then the safe parking speed of the current cycle is determined to be equal to the safe parking speed of the previous cycle.

[0036] Optionally, when the vehicle needs to enter a deceleration scenario, the deceleration for the current cycle is calculated based on the relationship between the deceleration of the previous cycle and the reference limit deceleration for the current cycle, including:

[0037] When the deceleration of the previous cycle is less than the reference limit deceleration of the current cycle, the deceleration of the current cycle is dcc = (ref_dcc_cr * t) + last_dcc, where ref_dcc_cr is the rate of change of the reference limit deceleration of the current cycle, last_dcc is the deceleration of the previous cycle, and t is the cycle of the algorithm.

[0038] When the deceleration of the previous cycle is greater than or equal to the reference limit deceleration of the current cycle, the deceleration of the current cycle is dcc = ref_dcc, where ref_dcc is the reference limit deceleration of the current cycle.

[0039] Optionally, when the vehicle needs to enter an acceleration scenario, the acceleration for the current cycle is calculated based on the relationship between the acceleration of the previous cycle and the reference limit acceleration for the current cycle, including:

[0040] When the acceleration of the previous cycle is less than the reference limit acceleration of the current cycle, calculate the acceleration of the current cycle: acc = (ref_acc_cr * t) + last_acc, where ref_acc_cr is the rate of change of the reference limit acceleration of the current cycle, last_acc is the acceleration of the previous cycle, and t is the cycle of the algorithm.

[0041] When the acceleration of the previous cycle is greater than or equal to the reference limit acceleration of the current cycle, the acceleration of the current cycle is calculated as acc = ref_acc, where ref_acc is the reference limit acceleration of the current cycle.

[0042] According to a second aspect of the present invention, a parking safety speed calculation system is provided, comprising:

[0043] The calibration module is used to calibrate vehicle body feature points;

[0044] The first acquisition module is used to determine the current driving scenario of the vehicle based on the current gear information of the vehicle, and to acquire the corresponding distance interval table and speed-related limit table based on the current driving scenario of the vehicle.

[0045] The second acquisition module is used to obtain the corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle feature point; and to obtain the speed-related limit data for the current period in the speed-related limit table according to the distance interval number.

[0046] The calculation module is used to calculate the safe parking speed for the current period based on the safe parking speed of the previous period and the speed-related limit data for the current period.

[0047] According to a third aspect of the present invention, an electronic device is provided, including a memory and a processor, wherein the processor is configured to execute a computer management program stored in the memory to implement a method for calculating a safe parking speed.

[0048] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer management class program is stored, wherein the computer management class program, when executed by a processor, implements the steps of a parking safety speed calculation method.

[0049] This invention provides a parking safety speed calculation method that adopts different strategies (speed planning parameters) for different vehicles and obstacles in different areas, and calculates the safe speed in real time. This method can optimize the risk introduced by insufficient obstacle detection accuracy, so that the target vehicle can decelerate in advance when passing obstacles to maintain a safe and controllable speed and avoid sudden braking or stopping. Attached Figure Description

[0050] Figure 1 A flowchart of a parking safety speed calculation method provided by the present invention;

[0051] Figure 2 A schematic diagram for calibrating vehicle body feature points;

[0052] Figure 3 A schematic diagram of blind spots in visual obstacle detection;

[0053] Figure 4 This is a schematic diagram of the blind zone for obstacle detection using ultrasonic radar.

[0054] Figure 5 A flowchart illustrating the process of calculating the safe parking speed for a given period;

[0055] Figure 6 A flowchart of a parking safety speed calculation method provided by the present invention;

[0056] Figure 7 A schematic diagram of a parking safety speed calculation system provided by the present invention;

[0057] Figure 8 A schematic diagram of the hardware structure of a possible electronic device provided by the present invention;

[0058] Figure 9 This is a schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined with each other to form feasible technical solutions. Such combinations are not constrained by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0060] This invention falls under the control category of the field of automatic parking. The core of automatic parking functionality includes sensor data perception, fusion, decision-making, planning, and control. Among these, speed planning is a crucial component of longitudinal control, affecting the comfort and safety of the vehicle during movement.

[0061] Based on this Figure 1 This invention provides a method for calculating a safe parking speed, which mainly includes the following steps:

[0062] S1, calibrate the vehicle body feature points.

[0063] As an example, the calibration of vehicle body feature points includes: establishing a vehicle coordinate system with the center of the rear wheel axle perpendicular to the vehicle's front as the X-axis and the rear wheel axle to the left as the Y-axis; selecting vehicle outer contour points as vehicle body feature points based on a preset clockwise angle of the vehicle's front wheel axle; selecting vehicle outer contour points as vehicle body feature points based on a preset clockwise angle of the vehicle's rear wheel axle; obtaining multiple vehicle body feature points by equally dividing the rear wheel axle and front wheel axle; and acquiring the coordinates of all vehicle body feature points in the vehicle coordinate system.

[0064] See also Figure 2This is a schematic diagram of the calibration of vehicle body feature points. The X-axis is perpendicular to the center of the rear wheel axle and forward along the front of the vehicle, and the Y-axis is to the left along the rear wheel axle to establish the vehicle coordinate system. After establishing the vehicle coordinate system, 32 vehicle body feature points are calibrated and numbered as CarEdge_P0-CarEdge_P31. The specific calibration process is as follows: (1) Based on the front wheel axle of the vehicle, the outer contour points of the vehicle are selected as the vehicle wheel library feature points, and the vehicle coordinates of these feature points are calibrated (which can be calibrated through the 2D model of the vehicle) to obtain feature points CarEdge_P0-CarEdge_P12. (2) Based on the rear wheel axle of the vehicle, the outer contour points of the vehicle are selected as the vehicle wheel library feature points, and the vehicle coordinates of these feature points are calibrated (which can be calibrated through the 2D model of the vehicle) to obtain feature points CarEdge_P16-CarEdge_P28. (3) Based on the rear axle and the front axle, 6 contour points CarEdge_P13-CarEdge_P15 and points CarEdge_P29-CarEdge_P31 are obtained by dividing the rear axle and the front axle into 3 equal parts. 32 body feature points of the vehicle are obtained through calibration.

[0065] S2 determines the current driving scenario of the vehicle based on the current gear information, and finds the corresponding distance interval table and speed-related limit table based on the current driving scenario.

[0066] As an example, the current driving scenario of the vehicle includes a forward scenario and a reverse scenario, and further includes: establishing corresponding distance interval tables and speed-related limit tables for the forward scenario and the reverse scenario respectively; wherein, the distance interval table records the correspondence between the distance range of the vehicle feature points in different positions of the vehicle body and the distance interval number; the speed-related limit table records the correspondence between the distance interval number and the speed-related limit data.

[0067] It is understandable that vehicles engage in both forward and reverse parking maneuvers. Different safe parking speed planning strategies are employed for these two scenarios. For both foreground and reverse parking scenarios, corresponding distance interval tables and speed-related limit tables are established. The distance interval table records the correspondence between the distance ranges of vehicle feature points within different areas of the vehicle body relative to obstacles and the distance interval numbers; the speed-related limit table records the correspondence between the distance interval numbers and speed-related limit data.

[0068] Specifically, when the vehicle is in a forward-moving scenario, the established distance interval table is shown in Table 1:

[0069] Table 1 Distance range in forward-moving scenarios

[0070]

[0071] As shown in Table 1, the vehicle body is divided into multiple different location regions, and the vehicle body feature points calibrated in step S1 can be assigned to the corresponding location regions. Among them, it can be based on... Figure 2 In a forward-moving scenario, CarEdge_P0-P2, CarEdge_P10-P16, and CarEdge_P28-P31 can be divided into the same position area, for example, called the first position area, representing the position area slightly in front of and to the sides of the vehicle; CarEdge_P3-P9 is divided into the second position area, representing the position area in front of the vehicle; and CarEdge_P13-P29 is divided into the third position area, representing the position area behind the vehicle.

[0072] It should be noted that when the distance interval number is 1, in the second position region, the distance range value is the variable value S, where S = v 2 / (2a)+k1*v+k2, where v represents the current vehicle speed, k1 is the equivalent delay time, and k2 is the equivalent safety distance. k1, k2, and a can be set empirically according to actual needs. In this invention, k1 = 0.2s, k2 = 0.25m, and a = 0.65m / s 2 .

[0073] When the vehicle is in a reverse scenario, the established distance interval table is shown in Table 2:

[0074] Table 2 Distance Ranges in Backward Scenarios

[0075]

[0076] As shown in Table 2, in the scenario of the vehicle reversing, CarEdge_P0-P2, CarEdge_P10-P16, and CarEdge_P28-P31 can be divided into the same position area, for example, called the first position area, which represents the position area slightly in front of and to the sides of the vehicle; CarEdge_P19-P25 is divided into the second position area, which represents the position area behind the vehicle; and CarEdge_P3-P9 is divided into the third position area, which represents the position area in front of the vehicle.

[0077] It should be noted that, as shown in Tables 1 and 2, for scenarios where the vehicle is moving forward, only obstacles in front of and to the sides of the vehicle are considered; for scenarios where the vehicle is reversing, only obstacles behind and to the sides of the vehicle are considered. The distance interval table records the correspondence between the distance ranges of obstacles and vehicle feature points in different areas of the vehicle body and the distance interval numbers.

[0078] For both forward and reverse vehicle scenarios, corresponding distance interval tables were established, and then corresponding speed-related limit tables were established separately. See Table 3 for the speed-related limit tables for the forward scenario:

[0079] Table 3 Speed-related limitations for forward-moving scenarios

[0080]

[0081] Similarly, see Table 4 for speed-related limitations in backward scenarios:

[0082]

[0083] According to Tables 3 and 4, the speed-related limit tables record the correspondence between distance interval numbers and speed-related limit data. The speed-related limit data includes reference limit speed, reference limit acceleration, reference limit deceleration, reference limit rate of change of acceleration, and reference limit rate of change of deceleration.

[0084] Thus, distance range tables and speed-related limit tables have been established for both forward and reverse vehicle scenarios.

[0085] S3. Based on the distance between the obstacle and the vehicle body feature points, find the corresponding distance interval number in the distance interval table.

[0086] As an example, obstacle information near the vehicle is obtained based on multi-sensor fusion, wherein the multi-sensor includes a visual sensor, an ultrasonic radar sensor, and a lidar sensor.

[0087] Understandably, using a single sensor to acquire information about obstacles around a vehicle would result in significant blind spots. (See also...) Figure 3 This is a schematic diagram of the blind spot in obstacle detection by a visual sensor. Figure 3 Four regions exhibit severe visual image distortion, and due to image cropping during stitching, blind spots will form in these areas based on optical flow and feature points, leading to SOD and MOD. Similarly, see [reference needed]. Figure 4 This is a schematic diagram of the blind zone for detecting obstacles using an ultrasonic sensor.

[0088] To address the blind spots inherent in using a single sensor for obstacle detection, this invention employs multi-sensor fusion to detect obstacles around the vehicle. Using the fused obstacle information for vehicle speed planning improves the reliability and stability of the planned speed output data, avoiding the risk of undetected obstacles in the blind spots of a single sensor leading to excessively high speeds.

[0089] After detecting obstacle information around the vehicle, as an example, the step of finding the corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle body feature points includes: calculating the distance between the obstacle and the vehicle body feature points in each location area; wherein, each location area includes multiple vehicle body feature points, and the minimum distance between the obstacle and the multiple vehicle body feature points in each location area is taken as the distance between the obstacle and the vehicle body feature points in each location area; based on the distance between the obstacle and the vehicle body feature points in each location area, and based on the correspondence between the distance range of the vehicle body feature points in each location area and the distance interval number, obtaining the corresponding distance interval number in each location area; and taking the minimum distance interval number as the distance interval number corresponding to the obstacle.

[0090] Understandably, the above process determines the current driving scenario based on the vehicle's current gear information, and then determines the corresponding distance range table and speed-related limit table based on the current driving scenario.

[0091] For example, if the vehicle is currently traveling forward, and the location is divided into regions as shown in Table 1, the distance between the obstacle and the vehicle's feature points within each region is calculated. The corresponding distance interval number is then obtained from Table 1. Each region contains multiple vehicle feature points. Therefore, when calculating the distance between the obstacle and each feature point within a region, the distance between the obstacle and each feature point within that region is calculated, and the minimum distance is taken as the distance between the obstacle and all feature points within that region. For instance, if there is an obstacle to the side of the vehicle, the distance between this obstacle and each vehicle feature point in the second region is calculated, and the minimum distance is taken. For example, if the minimum distance is 0.65m, and 0.65m is less than 0.7m (the distance interval number 3), then the distance interval number is 3. In other words, when the distance between the obstacle and a feature point in the second region is less than 0.7m but greater than 0.6m, the distance interval number is 3.

[0092] As an example, the obstacles include multiple obstacles. For any one obstacle, the distance interval number corresponding to the obstacle is obtained; each obstacle is traversed to obtain the distance interval number corresponding to each obstacle; the smallest distance interval number among all the distance interval numbers corresponding to the obstacles is taken as the final distance interval number corresponding to the obstacle.

[0093] It is understandable that when there are multiple obstacles around the vehicle, for each obstacle, the corresponding distance interval number is obtained according to the above method, and the smallest distance interval number among all the distance interval numbers corresponding to the obstacles is taken as the final distance interval number.

[0094] S4. Based on the distance interval number, obtain the speed-related limit data for this period from the speed-related limit table.

[0095] Understandably, step S3 above obtains the distance interval number of the obstacle relative to the vehicle, and retrieves the corresponding speed-related data from the corresponding speed-related limit table based on the distance interval number. For example, when the vehicle is in a forward-moving scenario, the corresponding speed-related data is retrieved from Table 3 above; when the vehicle is in a reverse-moving scenario, the corresponding speed-related data is retrieved from Table 4 above. The speed-related limit data includes reference limit vehicle speed ref_v, reference limit acceleration ref_acc, reference limit deceleration ref_dcc, reference limit deceleration rate of change ref_acc_cr, and reference limit deceleration rate of change ref_dcc_cr.

[0096] S5. Based on the safe parking speed of the previous cycle and the speed-related limit data of the current cycle, calculate the safe parking speed for the current cycle.

[0097] As an example, calculating the safe parking speed for the current period based on the safe parking speed of the previous period and the speed-related limit data for the current period includes: determining whether the vehicle needs to enter an acceleration or deceleration scenario based on the relationship between the safe parking speed of the previous period and the reference speed limit for the current period; when the vehicle needs to enter a deceleration scenario, calculating the deceleration for the current period based on the relationship between the deceleration of the previous period and the reference deceleration limit for the current period; when the vehicle needs to enter an acceleration scenario, calculating the acceleration for the current period based on the relationship between the acceleration of the previous period and the reference acceleration limit for the current period; calculating the safe parking speed for the current period based on the safe parking speed of the previous period and the deceleration of the current period, or calculating the safe parking speed for the current period based on the safe parking speed of the previous period and the acceleration of the current period.

[0098] It is understood that the flowchart for calculating the safe parking speed for the current period, based on the safe parking speed of the previous period and the speed-related limit data for the current period, can be found in [link to flowchart]. Figure 5 As an example, determining whether a vehicle needs to enter an acceleration or deceleration scenario based on the relationship between the safe parking speed of the previous cycle and the reference speed limit of the current cycle includes: when the safe parking speed of the previous cycle is greater than the reference speed limit of the current cycle, the vehicle needs to enter a deceleration scenario; when the safe parking speed of the previous cycle is less than the reference speed limit of the current cycle, the vehicle needs to enter an acceleration scenario; when the safe parking speed of the previous cycle is equal to the reference speed limit of the current cycle, then the safe parking speed of the current cycle is determined to be equal to the safe parking speed of the previous cycle.

[0099] Specifically, when a vehicle needs to enter a deceleration scenario, the deceleration for the current cycle is calculated based on the relationship between the deceleration of the previous cycle and the reference limit deceleration of the current cycle. This includes: when the deceleration of the previous cycle is less than the reference limit deceleration of the current cycle, the deceleration dcc of the current cycle is dcc = (ref_dcc_cr * t) + last_dcc, where ref_dcc_cr is the rate of change of the reference limit deceleration of the current cycle, last_dcc is the deceleration of the previous cycle, and t is the cycle of the algorithm; when the deceleration of the previous cycle is greater than or equal to the reference limit deceleration of the current cycle, the deceleration dcc of the current cycle is dcc = ref_dcc, where ref_dcc is the reference limit deceleration of the current cycle.

[0100] Specifically, when the vehicle needs to enter an acceleration scenario, the acceleration for the current cycle is calculated based on the relationship between the acceleration of the previous cycle and the reference limit acceleration of the current cycle. This includes: when the acceleration of the previous cycle is less than the reference limit acceleration of the current cycle, the acceleration for the current cycle is calculated as acc = (ref_acc_cr * t) + last_acc, where ref_acc_cr is the rate of change of the reference limit acceleration of the current cycle, last_acc is the acceleration of the previous cycle, and t is the cycle of the algorithm; when the acceleration of the previous cycle is greater than or equal to the reference limit acceleration of the current cycle, the acceleration for the current cycle is calculated as acc = ref_acc, where ref_acc is the reference limit acceleration of the current cycle.

[0101] After calculating the acceleration or deceleration for the current cycle, the safe parking speed for the current cycle is calculated based on the safe parking speed of the previous cycle and the deceleration of the current cycle, or vice versa. The calculation formula is v = last_v + a't, where a' is the acceleration or deceleration for the current cycle, v is the safe parking speed for the current cycle, and t is the cycle of the algorithm. This completes the calculation of the safe parking speed for the current cycle.

[0102] See Figure 6 This invention provides an overall flowchart of a parking safety speed calculation method. Based on the vehicle's coordinate system, vehicle feature points are calibrated. For both foreground and rearward scenarios, corresponding distance interval tables and speed-related limit tables are established. The distance interval table records the correspondence between the distances between obstacles and vehicle feature points in different locations and the distance interval numbers. The speed-related limit table records the correspondence between each distance interval number and speed-related data. The speed-related data includes reference limit speed, reference limit acceleration, reference limit deceleration, reference limit rate of change of acceleration, and reference limit rate of change of deceleration.

[0103] Subsequently, the vehicle's driving scenario is determined based on the gear information fed back from the vehicle chassis. Based on the driving scenario and the distance between the obstacle and the corresponding vehicle feature points in the area, the corresponding distance interval number is retrieved from the distance interval table. Then, based on the distance interval number, the corresponding speed-related data for the current cycle is retrieved from the corresponding speed-related limit table.

[0104] Based on the safe parking speed of the previous period and the speed-related data of the current period, calculate the safe parking speed for the current period.

[0105] See Figure 7 A parking safety speed calculation system is provided, comprising a calibration module 701, a first acquisition module 702, a second acquisition module 703, and a calculation module 704, wherein:

[0106] Calibration module 701 is used to calibrate vehicle body feature points;

[0107] The first acquisition module 702 is used to determine the current driving scenario of the vehicle based on the current gear information of the vehicle, and to acquire the corresponding distance interval table and speed-related limit table based on the current driving scenario of the vehicle.

[0108] The second acquisition module 703 is used to obtain the corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle feature point; and to obtain the speed-related limit data for the current period in the speed-related limit table according to the distance interval number.

[0109] The calculation module 704 is used to calculate the safe parking speed for the current period based on the safe parking speed of the previous period and the speed-related limit data for the current period.

[0110] It is understood that the parking safety speed calculation system provided by the present invention corresponds to the parking safety speed calculation method provided in the foregoing embodiments. The relevant technical features of the parking safety speed calculation system can be referred to the relevant technical features of the parking safety speed calculation method, and will not be repeated here.

[0111] Please see Figure 8 , Figure 8 This is a schematic diagram illustrating an embodiment of the electronic device provided in this invention. For example... Figure 8 As shown, an embodiment of the present invention provides an electronic device 800, including a memory 810, a processor 820, and a computer program 811 stored in the memory 810 and executable on the processor 820. When the processor 820 executes the computer program 811, it implements a method for calculating safe parking speed.

[0112] Please see Figure 9 , Figure 9 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided by the present invention. (See diagram below.) Figure 9 As shown, this embodiment provides a computer-readable storage medium 900, on which a computer program 911 is stored. When the computer program 911 is executed by a processor, it implements a method for calculating the safe parking speed.

[0113] This invention provides a method for calculating safe parking speed, which involves segmenting and calculating safe speed in real time across different areas. By using fused obstacle information for speed planning, the reliability and stability of the planned speed output data can be improved. This avoids the risk of speed planning being too fast due to obstacles appearing in the blind spots of a single sensor. At the same time, different strategies (speed planning parameters) are adopted for obstacles in different areas for different vehicles. Real-time calculation of safe speed can optimize the risk introduced by insufficient obstacle detection accuracy, enabling the target vehicle to decelerate in advance when passing obstacles to maintain a safe and controllable speed and avoid sudden braking or stopping.

[0114] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0115] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0116] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0118] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0119] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0120] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for calculating safe parking speed, characterized in that, include: Calibrate vehicle body feature points; Determine the current driving scenario of the vehicle based on the current gear information, and find the corresponding distance interval table and speed-related limit table based on the current driving scenario; Based on the distance between the obstacle and the vehicle's feature points, find the corresponding distance interval number in the distance interval table; Based on the distance interval number, obtain the speed-related limit data for this period from the speed-related limit table; The safe parking speed for the current period is calculated based on the safe parking speed of the previous period and the speed-related limit data for the current period.

2. The method for calculating safe parking speed according to claim 1, characterized in that, The calibrated vehicle body feature points include: The vehicle coordinate system is established with the center of the rear wheel axle perpendicular to the front of the vehicle as the X-axis and the center of the rear wheel axle perpendicular to the left of the rear wheel axle as the Y-axis. Based on a preset clockwise angle as the step size, the vehicle's outer contour points are selected as body feature points; and based on a preset clockwise angle as the step size, the vehicle's outer contour points are selected as body feature points; and multiple body feature points are obtained by equally dividing the vehicle's rear and front axles. Obtain the coordinates of all vehicle body feature points in the vehicle coordinate system.

3. The method for calculating safe parking speed according to claim 1, characterized in that, The current driving scenario of the vehicle includes forward and backward scenarios, and also includes: For forward and backward scenarios, establish corresponding distance interval tables and speed-related limit tables respectively; The distance interval table records the correspondence between the distance range of vehicle feature points in different locations of the vehicle and the distance interval number; The speed-related limit table records the correspondence between distance interval numbers and speed-related limit data.

4. The method for calculating safe parking speed according to claim 1, characterized in that, Information about obstacles near the vehicle is obtained based on multi-sensor fusion, wherein the multi-sensor includes a visual sensor, an ultrasonic radar sensor, and a lidar sensor.

5. The method for calculating safe parking speed according to claim 3, characterized in that, The method involves finding the corresponding distance interval number in the distance interval table based on the distance between the obstacle and the vehicle's feature points, including: Calculate the distance between the obstacle and the vehicle body feature points in each location area; wherein, each location area includes multiple vehicle body feature points, and the minimum distance between the obstacle and the multiple vehicle body feature points in each location area is taken as the distance between the obstacle and the vehicle body feature points in each location area. Based on the distance between the obstacle and the vehicle feature points in each location area, and based on the correspondence between the distance range of the vehicle feature points in each location area and the distance interval number, the corresponding distance interval number in each location area is obtained. Use the minimum distance interval number as the distance interval number corresponding to the obstacle.

6. The method for calculating safe parking speed according to claim 5, characterized in that, The obstacles include multiple obstacles. For any one obstacle, the distance interval number corresponding to that obstacle is obtained. Iterate through each obstacle and obtain the distance interval number corresponding to each obstacle; The smallest distance interval number among all distance interval numbers corresponding to obstacles is taken as the final distance interval number corresponding to the obstacle.

7. The method for calculating safe parking speed according to claim 1, characterized in that, The speed-related limit data includes reference limit speed, reference limit acceleration, reference limit deceleration, reference limit rate of change of acceleration, and reference limit rate of change of deceleration. The calculation of the safe parking speed for the current period based on the safe parking speed of the previous period and the speed-related limit data for the current period includes: Based on the relationship between the safe parking speed of the previous cycle and the reference speed limit of the current cycle, determine whether the vehicle needs to enter an acceleration or deceleration scenario. When a vehicle needs to enter a deceleration scenario, the deceleration for the current cycle is calculated based on the relationship between the deceleration of the previous cycle and the reference limit deceleration for the current cycle. When a vehicle needs to enter an acceleration scenario, the acceleration for the current cycle is calculated based on the relationship between the acceleration of the previous cycle and the reference limit acceleration for the current cycle. The safe parking speed for the current cycle can be calculated based on the safe parking speed of the previous cycle and the deceleration of the current cycle, or based on the safe parking speed of the previous cycle and the acceleration of the current cycle.

8. The method for calculating safe parking speed according to claim 7, characterized in that, The process of determining whether a vehicle needs to enter an acceleration or deceleration scenario based on the relationship between the safe parking speed of the previous cycle and the reference speed limit of the current cycle includes: When the safe parking speed of the previous cycle is greater than the reference speed limit of the current cycle, the vehicle needs to enter the deceleration scenario. When the safe parking speed of the previous cycle is less than the reference speed limit of the current cycle, the vehicle needs to enter the acceleration scenario; If the safe parking speed of the previous cycle equals the reference speed limit of the current cycle, then the safe parking speed of the current cycle is determined to be equal to the safe parking speed of the previous cycle.

9. The method for calculating safe parking speed according to claim 7, characterized in that, When the vehicle needs to enter a deceleration scenario, the deceleration for the current cycle is calculated based on the relationship between the deceleration of the previous cycle and the reference limit deceleration for the current cycle, including: When the deceleration of the previous cycle is less than the reference limit deceleration of the current cycle, the deceleration of the current cycle is dcc = (ref_dcc_cr*t) + last_dcc, where ref_dcc_cr is the rate of change of the reference limit deceleration of the current cycle, last_dcc is the deceleration of the previous cycle, and t is the cycle of the algorithm. When the deceleration of the previous cycle is greater than or equal to the reference limit deceleration of the current cycle, the deceleration of the current cycle is dcc = ref_dcc, where ref_dcc is the reference limit deceleration of the current cycle.

10. The method for calculating safe parking speed according to claim 7, characterized in that, When the vehicle needs to enter an acceleration scenario, the acceleration for the current cycle is calculated based on the relationship between the acceleration of the previous cycle and the reference limit acceleration for the current cycle, including: When the acceleration of the previous cycle is less than the reference limit acceleration of the current cycle, calculate the acceleration of the current cycle: acc = (ref_acc_cr * t) + last_acc, where ref_acc_cr is the rate of change of the reference limit acceleration of the current cycle, last_acc is the acceleration of the previous cycle, and t is the cycle of the algorithm. When the acceleration of the previous cycle is greater than or equal to the reference limit acceleration of the current cycle, the acceleration of the current cycle is calculated as acc = ref_acc, where ref_acc is the reference limit acceleration of the current cycle.

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