Forward collision early warning system key parameter verification method based on miniature sand table experiment platform

Abstract

The invention provides a forward collision early warning system key parameter verification method based on a miniature sand table experiment platform. The forward collision early warning system key parameter verification method comprises the steps of determining to-be-verified key parameters of a forward collision early warning system and a vehicle control instruction; the to-be-verified key parameter comprises any one of communication delay, communication packet loss rate, image resolution and perception precision; based on the miniature sand table experiment platform, according to the to-be-verified key parameters and the vehicle control instruction, controlling the miniature vehicle to perform simulated driving in the sand table platform, and obtaining actual driving data of the miniature vehicle in the simulated driving process; obtaining a verification result of the to-be-verified key parameter based on the actual driving data and pre-stored simulation driving data; the actual driving data comprises the collision time of the miniature vehicle and the front obstacle. According to the method, the key parameters of the forward collision early warning system are verified through the miniature sand table experiment platform, and accurate, safe and efficient verification of the key parameters of the forward collision early warning system is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle testing, and in particular to a key parameter verification method of a forward collision warning system based on a miniature sandbox experimental platform. Background Art

[0002] The Forward Collision Warning System (FCWS) is an important part of the active safety system of modern vehicles, which aims to improve driving safety. The system monitors the traffic conditions in front of the vehicle in real time and sends a warning signal to the driver when a potential collision risk is detected, thereby helping to avoid a collision or reduce the severity of the collision.

[0003] At present, the FCWS detection scheme mainly relies on the national standard GB / T 26773-2011 to ensure the safety and effectiveness of the factory system. Although GB / T 26773-2011 provides a series of basic safety performance requirements and test methods, it does not provide specific reference values ​​or optimization suggestions for the key indicator parameters of the data processing module in the forward collision warning system. This means that when manufacturers develop new forward collision warning systems, they need to design and implement a series of complex experiments to test and verify the optimal configuration of these key parameters to ensure the efficient operation of the system.

[0004] However, the existing test verification process is not only costly but also slow to iterate, and cannot meet the needs of the rapidly developing automotive industry for new forward collision warning systems. In addition, due to the lack of standardized guidelines, different manufacturers may adopt different test verification strategies, which may lead to uneven performance of products on the market and affect the overall level of road traffic safety.

[0005] Therefore, how to solve the problems of high cost, high safety risk and limitations of the existing forward collision warning system key parameter verification methods is an important issue that needs to be urgently solved in the field of vehicle testing. Summary of the invention

[0006] The present invention provides a forward collision warning system key parameter verification method based on a miniature sandbox experimental platform, which is used to overcome the defects of the existing forward collision warning system key parameter verification method, such as high cost, high safety risk and limitations, and realize accurate, safe and efficient verification of the key parameters of the forward collision warning system.

[0007] On the one hand, the present invention provides a method for verifying key parameters of a forward collision warning system based on a micro-scale sand table experiment platform. The micro-scale sand table experiment platform includes a micro-scale vehicle and a sand table platform, and is connected to the forward collision warning system through a wireless communication network. The method includes: determining the key parameters to be verified of the forward collision warning system and vehicle control instructions; wherein, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; based on the micro-scale sand table experiment platform, according to the key parameters to be verified and vehicle control instructions, controlling the micro-scale vehicle to perform simulated driving in the sand table platform, and obtaining the actual driving data of the micro-scale vehicle during the simulated driving; based on the actual driving data and pre-stored simulation driving data, obtaining the verification result of the key parameters to be verified; wherein, the actual driving data includes the collision time between the micro-scale vehicle and the obstacle in front, and the simulation driving data includes the simulated collision time between the micro-scale vehicle and the obstacle in front.

[0008] Further, the determining the key parameters to be verified of the forward collision warning system and vehicle control instructions includes: obtaining the current operating state information and environmental state information of the micro-scale vehicle in the micro-scale sand table experiment platform; generating vehicle control instructions according to the current operating state information and environmental state information of the micro-scale vehicle; wherein, the current operating state information includes pose information and speed information; the environmental state information includes traffic signal state information, street lamp state information, and lifting rod state information; the vehicle control instructions include the expected turning angle and expected speed of the micro-scale vehicle.

[0009] Further, the micro-scale sand table experiment platform includes one or more micro-scale vehicles, and the micro-scale vehicles are distinguished by different color block designs; correspondingly, the step of obtaining the current operating state information of the micro-scale vehicle in the micro-scale sand table experiment platform specifically includes: obtaining the global image of the sand table platform and the micro-scale vehicle; performing color space conversion on the global image to obtain an HSV image; performing binaryzation according to the H value of the pixel points in the HSV image to obtain an initial binaryzation image; performing convex polygon fitting on the initial binaryzation image, and calculating the minimum bounding rectangle of the convex polygon; in the case where the aspect ratio of the minimum bounding rectangle is within a set interval and the area of the minimum bounding rectangle is greater than a set area, taking the minimum bounding rectangle as the color block area on the top of the micro-scale vehicle to obtain the pose information of the micro-scale vehicle, and the pose information includes the position of the micro-scale vehicle.

[0010] Further, the step of obtaining the current operating state information of the micro-scale vehicle in the micro-scale sand table experiment platform specifically includes: obtaining the position of the micro-scale vehicle in adjacent frame global images; performing differential processing on the positions of the micro-scale vehicle in adjacent frame global images to obtain the change in the center point coordinates of the micro-scale vehicle; obtaining the speed information of the micro-scale vehicle according to the change in the center point coordinates of the micro-scale vehicle.

[0011] Further, obtaining the verification result of the key parameter to be verified based on the actual driving data and the pre-stored simulated driving data includes: when the difference between the collision time and the simulated collision time is less than or equal to a set threshold, determining that the verification result of the key parameter to be verified is qualified; when the difference between the collision time and the simulated collision time is greater than the set threshold, determining that the verification result of the key parameter to be verified is unqualified.

[0012] Further, the step of obtaining the actual driving data of the scaled vehicle during the simulated driving process specifically includes: using the camera configured on the scaled vehicle to obtain the target image in front of the scaled vehicle; performing target detection on the target image to obtain the upper and lower limits of the abscissa and the upper and lower limits of the ordinate of the front obstacle in the target image; calculating the relative distance from the front obstacle to the camera according to the height, downward deviation angle and focal length of the camera that captures the target image, and the upper and lower limits of the abscissa and the upper and lower limits of the ordinate; calculating the collision time according to the relative distance and the relative speed of the front obstacle and the scaled vehicle in the current running state to obtain the actual driving data.

[0013] Further, the sand table platform includes a structured road, a variety of roadside devices and a workstation. Among them, the structured road is used to provide a simulated driving scenario for the scaled vehicle; the roadside devices are arranged on the structured road and at least include street lights, traffic lights, parking lot lifting rods and cameras with global coverage; the workstation is connected to the roadside devices and the scaled vehicle at the same time, and is used to adjust the start and stop states of a variety of roadside devices, read the global image captured by the camera, and send the desired turning angle and desired vehicle speed to the scaled vehicle according to the read global image for the scaled vehicle to complete the response.

[0014] Second aspect, the present invention further provides a key parameter verification device for a forward collision warning system based on a scaled-down sand table experiment platform. The scaled-down sand table experiment platform includes a scaled-down vehicle and a sand table platform, and is connected to the forward collision warning system through a wireless communication network. The device includes: a key parameter to be verified and vehicle control instruction determination module, configured to determine the key parameter to be verified of the forward collision warning system and the vehicle control instruction; wherein, the key parameter to be verified includes any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; a simulated driving module of the scaled-down vehicle in the scaled-down sand table experiment platform, configured to control the scaled-down vehicle to perform simulated driving on the sand table platform based on the scaled-down sand table experiment platform, according to the key parameter to be verified and the vehicle control instruction, and obtain the actual driving data of the scaled-down vehicle during the simulated driving; a verification result acquisition module for the key parameter to be verified, configured to obtain the verification result of the key parameter to be verified based on the actual driving data and the pre-stored simulated driving data; wherein, the actual driving data includes the collision time between the scaled-down vehicle and the obstacle in front, and the simulated driving data includes the simulated collision time between the scaled-down vehicle and the obstacle in front.

[0015] Third aspect, the present invention further provides a key parameter verification system for a forward collision warning system based on a scaled-down sand table experiment platform, including: a scaled-down sand table experiment platform, including a physical sand table platform in the physical space and a twin sand table platform in the information space; wherein, the physical sand table platform includes a scaled-down vehicle and a sand table platform, and the sand table platform includes a structured road, a variety of roadside devices, and a workstation; the twin sand table platform is obtained by reconstructing the scene through 3D modeling based on the physical sand table platform, and is used to reflect the real-time operation state of the physical sand table platform; a computing server, including a forward collision warning system control unit, wirelessly connected to the scaled-down sand table experiment platform, and configured to execute the key parameter verification method for the forward collision warning system based on the scaled-down sand table experiment platform as described above.

[0016] Fourth aspect, the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the key parameter verification method for the forward collision warning system based on the scaled-down sand table experiment platform as described in any one of the above.

[0017] The key parameter verification method for the forward collision warning system based on the micro - scale sand table experimental platform provided by the present invention determines the key parameters to be verified for the forward collision warning system and vehicle control instructions; among them, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; based on the micro - scale sand table experimental platform, according to the key parameters to be verified and vehicle control instructions, control the micro - scale vehicle to perform simulated driving on the sand table platform, and collect the actual driving data of the micro - scale vehicle during the simulated driving process; based on the actual driving data and pre - stored simulation driving data, obtain the verification result of the key parameter to be verified; among them, the actual driving data includes the collision time between the micro - scale vehicle and the obstacle in front, and the simulation driving data includes the simulated collision time between the micro - scale vehicle and the obstacle in front. This method realizes the accurate, safe, and efficient verification of the key parameters of the forward collision warning system by using the micro - scale sand table experimental platform for key parameter verification of the forward collision warning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a system schematic diagram of the key parameter verification system for the forward collision warning system based on the micro - scale sand table experimental platform provided by the embodiments of the present invention.

[0020] Figure 2 It is a flow schematic diagram of the key parameter verification method for the forward collision warning system based on the micro - scale sand table experimental platform provided by the embodiments of the present invention.

[0021] Figure 3 It is a structural schematic diagram of the key parameter verification device for the forward collision warning system based on the micro - scale sand table experimental platform provided by the embodiments of the present invention.

[0022] Figure 4 It is a physical structure schematic diagram of the electronic device provided by the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention in conjunction with the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0024] It is easy to understand that before the key parameter verification method of the forward collision warning system based on the scaled sand table experimental platform provided by the embodiments of the present invention is described in detail, the verification system for implementing this verification method is first described here.

[0025] Figure 1 The system schematic diagram of the key parameter verification system of the forward collision warning system based on the scaled sand table experimental platform provided by the embodiments of the present invention is shown.

[0026] As Figure 1 shown, the system includes: a scaled sand table experimental platform, including a physical sand table platform in the physical space and a twin sand table platform in the information space; wherein, the physical sand table platform includes scaled vehicles and a sand table platform, and the sand table platform includes a structured road, a variety of roadside devices, multiple cameras, and a workstation; the twin sand table platform is obtained by reconstructing the scene through three-dimensional modeling based on the physical sand table platform, and is used to reflect the real-time operation state of the physical sand table platform; a computing server, including a forward collision warning system control unit, wirelessly connected to the scaled sand table experimental platform, and is used to execute the key parameter verification method of the forward collision warning system based on the scaled sand table experimental platform.

[0027] Specifically, the scaled sand table test platform is composed of a physical sand table platform in the physical space and a twin sand table platform in the information space. The physical sand table platform in the physical space is mainly composed of a structured road, roadside devices, a workstation, and scaled vehicles. Among them, the roadside devices and scaled vehicles are the main traffic elements considered.

[0028] The roadside devices all belong to information unidirectional transmission type devices, mainly including street lights, traffic lights, parking lot lifting poles, and cameras with full-area coverage. They are connected to the workstation through wired or serial ports. The workstation can adjust the states of roadside devices such as street lights, traffic lights, and parking lot lifting poles through serial communication. In addition, through wired connection, the workstation can read the images taken by the global cameras at a rate not lower than 10fps, and then calculate the relevant state information of the scaled vehicles based on the images.

[0029] In a specific embodiment, the sand table includes typical and rich road scenes such as intersections, roundabouts, parking lots, and bus stops, and can be used to simulate various typical urban traffic scenes. Among them, the length of the sand table is 9m, the width is 5m, the sand table road is composed of strict structured roads, the single-lane width is 240mm, and there are road structures such as two-way four-lane and two-way two-lane. The road yellow lines and green belts restrict the driving direction, and it is stipulated that the counterclockwise direction outside the yellow line near the edge of the sand table is the driving direction.

[0030] Meanwhile, 11 traffic lights and 73 street lights are deployed on the side of the sand table road, and 3 motor-controlled lifting poles are deployed at the entrance of the parking lot and on the green belt on the side of the center line parallel to the short axis. The traffic lights, street lights, and lifting poles communicate with the workstation responsible for overall information through serial ports. The workstation can change the real-time start / stop status by issuing serial port instructions, and each device can be independently controlled.

[0031] 4 cameras are deployed on the ceiling about 2.1m above the sand table plane. They are connected to the workstation through USB cables, achieving full coverage of the observation of the sand table plane. Among them, there is a certain overlapping area between each camera, and the width of the overlapping area is greater than or equal to the vehicle length. This deployment method ensures that the vehicle can be seamlessly detected even when crossing the camera boundary during driving.

[0032] The miniature vehicle belongs to the type of device with two-way information transmission. It is connected to the workstation through a local wireless network. The miniature vehicle can convert its own real-time motor speed into real-time speed and actively report it to the workstation; the workstation monitors the real-time running status of the miniature vehicle and sends the desired front wheel angle and desired vehicle speed to the miniature vehicle. The miniature vehicle can quickly complete the response without exceeding the allowed threshold range.

[0033] In a specific embodiment, the miniature vehicle used in this embodiment weighs 1.4 kg, and its length, width, and height are 200 mm, 180 mm, and 130 mm respectively. The wheelbase is 140 mm, and the wheel diameter is 60 mm. The miniature vehicle is equipped with a camera with a resolution of 640×480 and a single-line lidar. In addition, the miniature vehicle is also equipped with an IMU (Inertial Measurement Unit).

[0034] The miniature vehicle communicates with the sand table workstation through a local wireless network, obtains the motor speed, converts it into the real-time speed of the miniature vehicle and reports it. Generally, the maximum running speed of the miniature vehicle can reach 1 m / s, and the battery can continuously supply power for about 3.5 hours. In terms of in-vehicle computing power, the upper computer of the miniature vehicle is a Raspberry Pi 4B installed with Ubuntu1804, and the lower computer main control chip is STM32F103RBT6. The CPU of the upper computer is a 64-bit quad-core processor with a main frequency of 1.5 GHz, with 2G of memory and 16G of storage. Based on the in-vehicle sensing devices and computing units, the miniature vehicle can achieve a certain degree of in-vehicle environment perception.

[0035] The twin sandbox platform in the cyber space is mainly composed of the one-to-one twins (twin miniature vehicles) of the roadside equipment and miniature vehicles in the physical space and virtual vehicles. The twins complete the scene reconstruction based on real-time communication through 3D modeling and interface design, so that they can reflect the real-time operation status of the corresponding physical elements. Virtual vehicles are used to represent physical miniature vehicles through similar dynamics and kinematics modeling.

[0036] This embodiment can complete the modeling of information space based on the game engine Unity3D, and adjust the corresponding state parameters of the twin body by obtaining the real-time operating status of each traffic element in the physical space to achieve real-time state mapping. For virtual vehicles, their information flow interaction is similar to that of miniature vehicles in the physical space. By reporting their real-time state information, including but not limited to speed, position and direction, to the host running Unity (i.e. Figure 1 The Unity host in the image processing unit sends the desired front wheel steering angle and speed instructions to it.

[0037] Compute Server (i.e. Figure 1 The cloud-based Java server in the middle establishes connections with workstations in the physical space and Unity hosts in the information space to obtain the real-time status of each traffic element in the physical space and the virtual vehicle in the information space, and aligns and encapsulates all status information through time synchronization and predetermined protocols.

[0038] It is worth mentioning that, unlike the cloud of the intelligent connected vehicle cloud control system, the cloud described in this embodiment integrates complete status data of the information space and the physical space, and opens it to the outside through certain protocols. For external programs, they can obtain real-time status data of the system by establishing a connection with the cloud to realize corresponding applications.

[0039] according to Figure 1 It can be seen that the forward collision warning system key parameter verification system based on the miniature sandbox experimental platform provided in this embodiment can provide the vehicle status data to the external controller, and under the premise of ensuring safety, it can also apply the converted external control instructions to the miniature vehicle end. For the external controller, it receives the real-time status data of the miniature vehicle, generates the control instructions of the miniature vehicle after calculation, and does not need to pay attention to the specific implementation details inside the system.

[0040] To accommodate the access of external controllers with different requirements, three types of vehicle control modes are opened in the cloud in this embodiment. The parameters and meanings corresponding to each vehicle control mode are as follows: (1) Desired front wheel angle and speed; (2) Waypoints. A waypoint is the desired position of the scaled vehicle. Generally, waypoints are often discrete points on the center line of the road, and the set of waypoints constitutes the desired trajectory of the scaled vehicle over a period of time. To enable the scaled vehicle to reach the position indicated by the waypoint while satisfying the road geometry constraints, waypoints usually include information such as coordinates and reference speed; (3) Map nodes. The map nodes referred to in this embodiment are large-scale diverging or converging points of vehicle queues, usually referring to the starting and ending points of lanes on structured roads. To enable the scaled vehicle to reach the position indicated by the map node at the minimum cost while satisfying the road geometry constraints, map nodes usually include information such as numbers, coordinates, and the numbers of the downstream nodes connected to them.

[0041] While ensuring the driving safety of the vehicle, the above three vehicle control modes open to the outside also provide a certain degree of flexibility, capable of meeting the vehicle control requirements of different external controllers.

[0042] According to Figure 1 It can also be seen that in addition to external controllers, human-machine interaction devices can also be applied to external inputs. To implement the input of human intention, in this embodiment, the Hololens device can be used to capture the behavior of the wearer, and based on the preset behavior / logic correspondence, the behavior of the wearer is converted into the corresponding intention input. Similarly, to achieve the visualization of the information space, the established model can be projected onto the three-dimensional space in the form of a hologram based on the Hololens device, providing a three-dimensional immersive observation perspective for the wearer.

[0043] To implement HDV simulation and provide the driver with a first-person driving perspective, in this embodiment, based on the driving simulator, the real-time operating state of the scene is obtained to update each model parameter, and a first-person driving perspective is provided to the driver; at the same time, by collecting the driver's input control information, including throttle opening information, gear information, steering wheel angle information, etc., it is fed back to the scaled vehicle in the system, thereby simulating human driving of a car.

[0044] In this embodiment, the key parameter verification system for the forward collision warning system based on the micro - scale sand table experiment platform includes a micro - scale sand table experiment platform and a computing server. The micro - scale sand table experiment platform includes a physical sand table platform in the physical space and a twin sand table platform in the information space. Among them, the physical sand table platform includes a micro - vehicle and a sand table platform. The sand table platform includes a structured road, a variety of roadside devices, and a workstation. The twin sand table platform is obtained by reconstructing the scene through 3D modeling based on the physical sand table platform and is used to reflect the real - time operation state of the physical sand table platform. The computing server includes a forward collision warning system control unit, which is wirelessly connected to the micro - scale sand table experiment platform and is used to execute the key parameter verification method for the forward collision warning system based on the micro - scale sand table experiment platform. This system effectively improves the safety, efficiency, and controllability of the key parameter verification of the forward collision warning system.

[0045] Furthermore, based on the key parameter verification system for the forward collision warning system based on the micro - scale sand table experiment platform provided in the above - mentioned embodiment, the key parameter verification method for the forward collision warning system based on the micro - scale sand table experiment platform is executed. Specifically, Figure 2 Fig. shows the flow chart of the key parameter verification method for the forward collision warning system based on the micro - scale sand table experiment platform provided by the embodiment of the present invention.

[0046] As Figure 2 shown, this method includes steps S210 - S230, and the following will elaborate on steps S210 - S230 and related steps in detail.

[0047] S210, determine the key parameters to be verified for the forward collision warning system and the vehicle control command; among them, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy.

[0048] It should be noted that the key parameter verification method for the forward collision warning system based on the micro - scale sand table experiment platform provided by the embodiment of the present invention takes the computing server in the system as the execution entity.

[0049] It is easy to understand that based on the key parameter verification system for the forward collision warning system based on the micro - scale sand table experiment platform provided in the above - mentioned embodiment, by obtaining the current operation state information and environmental state information of the micro - vehicle in the micro - scale sand table experiment platform, the computing server can generate corresponding vehicle control commands. At the same time, the computing server will also determine the key parameters of the forward collision warning system to be verified currently, that is, the key parameters to be verified.

[0050] Specifically, through the cameras with global coverage in the micro-scale sand table experiment platform, the state information of the entire sand table platform and the micro-scale vehicles can be captured, including but not limited to road network structure information, lane geometry information, the correspondence information between lane IDs and colors, and the overall global image. Based on these perceived state information, the pose information and speed information of the micro-scale vehicles, that is, the current running state information of the micro-scale vehicles, can be calculated through vehicle detection and state output algorithms.

[0051] Meanwhile, the start-stop state information of traffic lights, street lights, and parking lot lift bars can be obtained from the workstation. For this information, an edge cloud (cloud computing model) method can be used for integration to obtain the integrated environment information, that is, the environmental state information.

[0052] Subsequently, according to the current running state information of the micro-scale vehicles and the environmental state information, the desired front wheel angle and speed of the micro-scale vehicles can be determined, thereby generating corresponding vehicle control commands.

[0053] It should be noted that since this embodiment verifies the key parameters of the forward collision warning system, when the micro-scale vehicles are driving in simulation according to the vehicle control commands, the forward collision warning system should be triggered.

[0054] In addition, the key parameters to be verified in the forward collision warning system in this embodiment include but are not limited to communication delay, communication packet loss rate, image resolution, and perception accuracy. However, when verifying the key parameters of the forward collision warning system, only any one of the communication delay, communication packet loss rate, image resolution, and perception accuracy is selected for each verification. That is to say, the key parameters to be verified such as communication delay, communication packet loss rate, image resolution, and perception accuracy are in an "or" relationship during verification, rather than an "and" relationship.

[0055] Among them, the type of the key parameters to be verified can be determined according to actual requirements / situations, and no specific limitation is made here. The values of the key parameters to be verified are obtained according to a predetermined simulation test algorithm.

[0056] Communication delay refers to the time required for the information to be completely received at the receiving end from the sending end during the network data transmission process, which can be controlled by using a network emulator or built-in tools of the operating system. Communication packet loss rate refers to the proportion of data packets that fail to reach the destination successfully in the total sent data packets during the network data transmission process, which can be controlled by using a network emulator. Image resolution refers to the number of pixels contained in an image. A higher resolution means that the image contains more details and information, which can be controlled by changing the performance parameters of the camera. Perception accuracy refers to the accuracy of the perception model used to detect and predict the state of the micro-scale vehicles, which can be controlled by changing the model parameters of the perception model.

[0057] Specifically, the control of communication delay / communication packet loss rate mainly aims at detecting the distance between the miniature vehicle and the obstacle ahead by relying on the camera in an unreliable communication scenario. There is a time delay in the position, which causes the forward collision warning system to receive a parking position that lags behind the actual parking position. As a result, the actual parking position of the vehicle lags behind the theoretical parking position, leading to a forward collision.

[0058] In addition, in a communication network, data transmission usually has burstiness. That is, after a data is lost during transmission, the probability of the next data being lost is greater than the probability of successful transmission. Therefore, packet loss may occur. The control of image resolution mainly considers detecting the distance between the miniature vehicle and the forward obstacle through the camera. So the camera resolution will affect the forward collision warning performance of the system. The control of the perception accuracy of the perception model mainly considers that the accuracy of detecting the relative distance between the miniature vehicle and the obstacle ahead based on the camera in the system will directly affect the output accuracy of the system.

[0059] After determining the key parameters to be verified and the vehicle control instructions of the forward collision warning system, the computing server will transmit the key parameters to be verified and the vehicle control instructions to the miniature sand table experiment platform to execute step S220.

[0060] S220. Based on the miniature sand table experiment platform, according to the key parameters to be verified and the vehicle control instructions, control the miniature vehicle to perform simulated driving on the sand table platform, and obtain the actual driving data of the miniature vehicle during the simulated driving process.

[0061] It is easy to understand that after receiving the key parameters to be verified, the values of the key parameters to be verified are controlled / adjusted, such as increasing communication delay, increasing communication packet loss rate, reducing image resolution, or reducing the perception accuracy of the perception model, etc.

[0062] After adjusting the key parameters to be verified, according to the vehicle control instructions, adjust the front wheel angle of the miniature vehicle with the expected angle as the target, and adjust the speed of the miniature vehicle with the expected speed as the target, thereby controlling the miniature vehicle to perform simulated driving on the sand table platform. At the same time, based on the cameras with global coverage and various installed sensor devices, collect the actual driving data of the miniature vehicle during the entire simulated driving process. The actual driving data here includes the collision time between the miniature vehicle and the obstacle ahead.

[0063] After collecting the actual driving data of the miniature vehicle during the simulated driving process, transmit the actual driving data to the computing server to execute step S230.

[0064] S230. Obtain the verification result of the key parameter to be verified based on the actual driving data and the pre-stored simulated driving data. Wherein, the actual driving data includes the collision time between the scaled vehicle and the obstacle ahead, and the simulated driving data includes the simulated collision time between the scaled vehicle and the obstacle ahead.

[0065] It is easy to understand that the simulated driving data corresponding to the key parameter to be verified is pre-stored in the system, and the simulated driving data includes the simulated collision time between the scaled vehicle and the obstacle ahead. After obtaining the actual driving data (including the collision time) of the key parameter to be verified, compare the actual driving data with the corresponding simulated driving data, and thus the verification result of the key parameter to be verified can be obtained.

[0066] Specifically, calculate the difference between the collision time obtained in the verification process and the simulated collision time obtained in the simulation test process. If the difference between the two is less than or equal to the set threshold, it indicates that the verification result of the current key parameter to be verified is qualified; otherwise, if the difference between the two is greater than the set threshold, it indicates that the verification result of the current key parameter to be verified is unqualified, and the simulation test process needs to be adjusted again.

[0067] Among them, the set threshold can be adjusted according to the actual situation, and no specific limitation is made here.

[0068] It is worth mentioning that this embodiment verifies the key parameters of the forward collision warning system, but this embodiment also verifies the simulation test algorithm for determining the key parameters to be verified. If the simulation test method is accurate and effective, the key parameters to be verified determined by it must be verified to be qualified; otherwise, if the simulation test method has poor effects, the key parameters to be verified determined by it will cause the forward collision warning system to be unable to complete the forward collision warning or the forward collision warning effect is poor.

[0069] In this embodiment, determine the key parameter to be verified and the vehicle control instruction of the forward collision warning system. Wherein, the key parameter to be verified includes any one of communication delay, communication packet loss rate, image resolution, and perception accuracy. Based on the scaled sand table experiment platform, according to the key parameter to be verified and the vehicle control instruction, control the scaled vehicle to perform simulated driving on the sand table platform, and collect the actual driving data of the scaled vehicle during the simulated driving process. Obtain the verification result of the key parameter to be verified based on the actual driving data and the pre-stored simulated driving data. Wherein, the actual driving data includes the collision time between the scaled vehicle and the obstacle ahead, and the simulated driving data includes the simulated collision time between the scaled vehicle and the obstacle ahead. This method realizes the accurate, safe, and efficient verification of the key parameters of the forward collision warning system by using the scaled sand table experiment platform to verify the key parameters of the forward collision warning system.

[0070] Based on the above embodiments, further, the process of obtaining the current operating state information of the miniature vehicle will be described in detail below.

[0071] It is easy to understand that the current operating state information of the miniature vehicle includes pose information and speed information. Therefore, this embodiment mainly describes in detail the process of obtaining the pose information and speed information.

[0072] To achieve the state perception of the miniature vehicle, real-time perception of the miniature vehicle is realized based on the global camera and the color block design on the top of the miniature vehicle. Its essence is an image processing algorithm, that is, the detection and state perception of the vehicle are realized by detecting different color block combinations of different miniature vehicles.

[0073] In a specific embodiment, the process of obtaining the pose information of the miniature vehicle is described in detail.

[0074] The steps of obtaining the current operating state information of the miniature vehicle in the miniature sand table experiment platform specifically include: obtaining the global image of the sand table platform and the miniature vehicle; performing color space conversion on the global image to obtain an HSV image; performing binarization according to the H value of the pixel points in the HSV image to obtain a binarized image; performing convex polygon fitting on the binarized image and calculating the minimum bounding rectangle of the convex polygon; when the aspect ratio of the minimum bounding rectangle is within a set interval and the area of the minimum bounding rectangle is greater than a set area, taking the minimum bounding rectangle as the color block area on the top of the miniature vehicle to obtain the pose information of the miniature vehicle, and the pose information includes the position of the miniature vehicle.

[0075] Specifically, the perception of the pose information of the miniature vehicle can be realized based on a single-frame global image, and the following steps are required: color space conversion, edge extraction and graphic filtering, coordinate and orientation calculation and output.

[0076] Color space is one of the ways to describe colors. By abstractly representing colors in a high-dimensional space, colors correspond one-to-one with points in the color space, making the description of colors more intuitive. Since the global image collected by the global camera is based on the RGB color space, it needs to be converted to the HSV color space during subsequent processing. For the color value of any pixel point in the global image, convert it from RGB to the HSV color space to obtain an HSV image.

[0077] To extract the information of miniature vehicles, i.e., the color block combination information at the top of each vehicle, from an image represented in the HSV color space (HSV image), the colors at the rear, front, and middle of the miniature vehicle body are sequentially searched in the HSV image. During the search process, the main parameter is the H value of the pixel points in the HSV image, and the HSV image is converted into the required binary image based on the H value of the pixel points. Due to the possible presence of the colors to be detected and noise in the scene background, the initial binary image often contains multiple regions to be screened. To screen out the target vehicle from multiple regions to be screened, the regions to be screened need to be filtered.

[0078] When filtering, first, convex polygon fitting needs to be performed on the binary image at the pixel level, then the minimum bounding rectangle of the convex polygon is calculated, and finally, screening is performed based on the geometric features of the minimum bounding rectangle. Considering that the imaging diagram of the designed rectangular color block may be deformed and the geometric parameters of the minimum bounding rectangle may fluctuate as the distance between the miniature vehicle and the global camera changes during the driving process of the miniature vehicle. For the result of whether the region to be screened is the target color block, when the aspect ratio of the minimum bounding rectangle is within a certain range and the area is greater than the threshold, it is determined that the region to be selected is the color block region at the top of the vehicle, and thus the pose information of the miniature vehicle, including the position and orientation of the miniature vehicle, can be determined.

[0079] In another specific embodiment, the process of obtaining the speed information of the miniature vehicle is described in detail.

[0080] It is easy to understand that there are two schemes for obtaining the real-time running speed of the miniature vehicle. One is to perform differentiation on the positions of the miniature vehicle in adjacent frames of the global image to obtain the change in the center point coordinates of the miniature vehicle; the other is based on the communication between the miniature vehicle and the sand table workstation, and the miniature vehicle converts its own motor speed into the real-time speed and reports it.

[0081] In the scheme where the miniature vehicle actively reports its speed, the upper computer of the miniature vehicle is a Raspberry Pi 4B with the Ubuntu18.04 system installed, and the lower computer main control chip is STM32. The Raspberry Pi and the sand table host are located in the same local area network and communicate wirelessly. The sand table host sends the desired speed and the front wheel angle to the Raspberry Pi at a frequency of 20Hz, and the Raspberry Pi sends the desired speed and the front wheel angle command to the lower computer based on serial communication at a frequency of 120Hz. The lower computer sends the corresponding control command to the execution device of the miniature vehicle at a frequency of 20Hz. The vehicle obtains the state of mechanical devices such as the motor, such as the rotation speed, and then converts it into the corresponding vehicle speed, and finally reports the estimated vehicle speed to the sand table host at a frequency of 20Hz based on wireless communication.

[0082] In this embodiment, the key parameters to be verified of the forward collision warning system and vehicle control instructions are determined; wherein, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; based on the scaled-down sand table experimental platform, according to the key parameters to be verified and vehicle control instructions, the scaled-down vehicle is controlled to perform simulated driving on the sand table platform, and the actual driving data of the scaled-down vehicle during the simulated driving is collected; based on the actual driving data and the pre-stored simulated driving data, the verification result of the key parameters to be verified is obtained; wherein, the actual driving data includes the collision time between the scaled-down vehicle and the obstacle ahead, and the simulated driving data includes the simulated collision time between the scaled-down vehicle and the obstacle ahead. This method realizes the accurate, safe, and efficient verification of the key parameters of the forward collision warning system by using the scaled-down sand table experimental platform to verify the key parameters of the forward collision warning system.

[0083] In some embodiments, the step of obtaining the actual driving data of the scaled-down vehicle during the simulated driving specifically includes: using the camera configured on the scaled-down vehicle to obtain the target image in front of the scaled-down vehicle; performing target detection on the target image to obtain the upper and lower limits of the abscissa and the upper and lower limits of the ordinate of the obstacle ahead in the target image; according to the height, downward deflection angle, and focal length of the camera that captures the target image, and the upper and lower limits of the abscissa and the upper and lower limits of the ordinate, calculate the relative distance from the obstacle ahead to the camera; calculate the collision time according to the relative distance and the relative speed of the obstacle ahead and the scaled-down vehicle in the current running state to obtain the actual driving data.

[0084] In some other embodiments, if the collision time is less than the first set threshold, the forward collision warning system control unit in the calculation server will send a forward collision warning message to the scaled-down vehicle.

[0085] Wherein, the first set threshold can be adjusted according to the actual situation and is not specifically limited herein.

[0086] Corresponding to the method for verifying the key parameters of the forward collision warning system based on the scaled-down sand table experimental platform described in the above embodiments, the present invention also provides a device for verifying the key parameters of the forward collision warning system based on the scaled-down sand table experimental platform.

[0087] Specifically, Figure 3 The structural schematic diagram of the device for verifying the key parameters of the forward collision warning system based on the scaled-down sand table experimental platform provided by the embodiment of the present invention is shown.

[0088] As Figure 3As shown in the figure, the device includes: a key parameter to be verified and vehicle control instruction determination module 310, configured to determine the key parameters to be verified and vehicle control instructions of the forward collision warning system; wherein, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; a miniature vehicle simulation driving module 320 in the miniature sand table experiment platform, configured to, based on the miniature sand table experiment platform, control a miniature vehicle to perform simulated driving on the sand table platform according to the key parameters to be verified and vehicle control instructions, and obtain actual driving data of the miniature vehicle during the simulated driving process; a verification result acquisition module 330 for the key parameters to be verified, configured to obtain a verification result of the key parameters to be verified based on the actual driving data and pre-stored simulation driving data; wherein, the actual driving data includes the collision time between the miniature vehicle and an obstacle ahead, and the simulation driving data includes the simulated collision time between the miniature vehicle and an obstacle ahead.

[0089] In this embodiment, the key parameter to be verified and vehicle control instruction determination module 310 determines the key parameters to be verified and vehicle control instructions of the forward collision warning system; wherein, the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; the miniature vehicle simulation driving module 320 in the miniature sand table experiment platform controls a miniature vehicle to perform simulated driving on the sand table platform according to the key parameters to be verified and vehicle control instructions based on the miniature sand table experiment platform, and obtains actual driving data of the miniature vehicle during the simulated driving process; the verification result acquisition module 330 for the key parameters to be verified obtains a verification result of the key parameters to be verified based on the actual driving data and pre-stored simulation driving data; wherein, the actual driving data includes the collision time between the miniature vehicle and an obstacle ahead, and the simulation driving data includes the simulated collision time between the miniature vehicle and an obstacle ahead. By using the miniature sand table experiment platform to verify the key parameters of the forward collision warning system, the device realizes accurate, safe, and efficient verification of the key parameters of the forward collision warning system.

[0090] It should be noted that the key parameter verification device for the forward collision warning system based on the miniature sand table experiment platform provided in the embodiments of the present invention can be correspondingly referred to the key parameter verification method for the forward collision warning system based on the miniature sand table experiment platform described in the above embodiments, and will not be elaborated here.

[0091] Figure 4 The schematic physical structure diagram of an electronic device is exemplified, such as Figure 4As shown, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communication bus 440. Among them, the processor 410, the communications interface 420, and the memory 430 complete communication with each other through the communication bus 440. The processor 410 may call the logical instructions in the memory 430 to execute a method for verifying key parameters of a forward collision warning system based on a micro-scale sand table experiment platform. The method includes: determining the key parameters to be verified of the forward collision warning system and vehicle control instructions; where the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution, and perception accuracy; based on the micro-scale sand table experiment platform, according to the key parameters to be verified and the vehicle control instructions, controlling a micro-scale vehicle to perform simulated driving on the sand table platform, and obtaining the actual driving data of the micro-scale vehicle during the simulated driving; based on the actual driving data and the pre-stored simulated driving data, obtaining the verification result of the key parameters to be verified; where the actual driving data includes the collision time between the micro-scale vehicle and the obstacle in front, and the simulated driving data includes the simulated collision time between the micro-scale vehicle and the obstacle in front.

[0092] In addition, when the logical instructions in the above-mentioned memory 430 are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0093] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative labor.

[0094] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for verifying key parameters of a forward collision warning system based on a miniature sandbox experimental platform, characterized in that: The miniature sandbox experimental platform includes a miniature vehicle and a sandbox platform, which are connected to the forward collision warning system via a wireless communication network; The method comprises: Determining key parameters to be verified of the forward collision warning system and vehicle control instructions; wherein the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution and perception accuracy; Based on the miniature sandbox experimental platform, according to the key parameters to be verified and the vehicle control instructions, the miniature vehicle is controlled to perform simulated driving in the sandbox platform, and actual driving data of the miniature vehicle during the simulated driving process is obtained; Based on the actual driving data and the pre-stored simulated driving data, the verification result of the key parameter to be verified is obtained; wherein the actual driving data includes the collision time between the miniature vehicle and the obstacle ahead, and the simulated driving data includes the simulated collision time between the miniature vehicle and the obstacle ahead.

2. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to claim 1 is characterized in that: The step of determining the key parameters to be verified of the forward collision warning system and the vehicle control instructions includes: Obtain the current operating status information and environmental status information of the miniature vehicle in the miniature sandbox experimental platform; Generate vehicle control instructions according to the current operating state information and environmental state information of the miniature vehicle; Among them, the current running state information includes posture information and speed information; the environmental state information includes signal light state information, street light state information and lifting pole state information; the vehicle control instruction includes the expected turning angle and expected speed of the miniature vehicle.

3. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to claim 2 is characterized in that: The miniature sandbox experimental platform includes one or more miniature vehicles, and the miniature vehicles are distinguished by different color block designs; Accordingly, the step of obtaining the current running status information of the miniature vehicle in the miniature sandbox experimental platform specifically includes: Get the global image of the sandbox platform and miniature vehicles; Performing color space conversion on the global image to obtain an HSV image; Binarize the image according to the H value of the pixel in the HSV image to obtain an initial binary image; Performing convex polygon fitting on the initial binary image, and calculating the minimum envelope rectangle of the convex polygon; When the aspect ratio of the minimum envelope rectangle is within a set range and the area of ​​the minimum envelope rectangle is greater than the set area, the minimum envelope rectangle is used as the color block area on the top of the miniature vehicle to obtain the posture information of the miniature vehicle, wherein the posture information includes the position of the miniature vehicle.

4. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to claim 2 is characterized in that: The steps of obtaining the current running status information of the miniature vehicle in the miniature sandbox experimental platform specifically include: Obtaining the position of the miniature vehicle in the global image of the adjacent frames; Perform differential processing on the position of the miniature vehicle in the global image of adjacent frames to obtain the change of the coordinates of the center point of the miniature vehicle; The speed information of the miniature vehicle is obtained according to the change of the coordinates of the center point of the miniature vehicle.

5. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to claim 1 is characterized in that: The obtaining the verification result of the key parameter to be verified based on the actual driving data and the pre-stored simulated driving data includes: When the difference between the collision time and the simulated collision time is less than or equal to a set threshold, determining the verification result of the key parameter to be verified as qualified; When the difference between the collision time and the simulated collision time is greater than a set threshold, the verification result of the key parameter to be verified is determined as verification failure.

6. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to claim 3 is characterized in that: The steps of obtaining actual driving data of the miniature vehicle during the simulated driving process specifically include: Using the camera configured on the miniature vehicle, the target image in front of the miniature vehicle is acquired; Performing target detection on the target image to obtain upper and lower limits of the horizontal coordinate and upper and lower limits of the vertical coordinate of the front obstacle in the target image; Calculate the relative distance from the front obstacle to the camera according to the height, downward deflection angle and focal length of the camera shooting the target image, as well as the upper and lower limits of the horizontal coordinate and the upper and lower limits of the vertical coordinate; The collision time is calculated according to the relative distance and the relative speed of the front obstacle and the miniature vehicle in the current running state to obtain the actual driving data.

7. The key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform according to any one of claims 1 to 6, characterized in that: The sandbox platform includes a structured road, a variety of roadside equipment and a workstation, wherein: The structured road is used to provide a simulated driving scenario for the miniature vehicle; The roadside equipment is arranged on the structured road and includes at least street lights, traffic lights, parking lot lifting poles and cameras with global coverage; The workstation is connected to the roadside equipment and the miniature vehicle at the same time, and is used to adjust the start and stop status of various road test equipment, read the global image taken by the camera, and send the expected turning angle and expected vehicle speed to the miniature vehicle according to the read global image, so that the miniature vehicle can complete the response.

8. A forward collision warning system key parameter verification device based on a miniature sandbox experimental platform, characterized in that: The miniature sandbox experimental platform includes a miniature vehicle and a sandbox platform, which are connected to the forward collision warning system via a wireless communication network; The device comprises: A module for determining key parameters to be verified and vehicle control instructions, used to determine key parameters to be verified and vehicle control instructions of a forward collision warning system; wherein the key parameters to be verified include any one of communication delay, communication packet loss rate, image resolution and perception accuracy; A miniature vehicle simulation driving module in a miniature sandbox experimental platform is used to control the miniature vehicle to perform simulated driving in the sandbox platform based on the miniature sandbox experimental platform according to the key parameters to be verified and the vehicle control instructions, and obtain actual driving data of the miniature vehicle during the simulated driving process; The module for obtaining verification results of key parameters to be verified is used to obtain verification results of the key parameters to be verified based on actual driving data and pre-stored simulated driving data; wherein the actual driving data includes the collision time between the miniature vehicle and the obstacle ahead, and the simulated driving data includes the simulated collision time between the miniature vehicle and the obstacle ahead.

9. A forward collision warning system key parameter verification system based on a miniature sandbox experimental platform, characterized in that: include: A miniature sandbox experimental platform, including a physical sandbox platform in physical space and a twin sandbox platform in information space; wherein the physical sandbox platform includes a miniature vehicle and a sandbox platform, and the sandbox platform includes a structured road, a variety of roadside equipment, and a workstation; the twin sandbox platform is obtained by reconstructing the scene through three-dimensional modeling based on the physical sandbox platform, and is used to reflect the real-time operation status of the physical sandbox platform; A computing server, including a forward collision warning system control unit, is wirelessly connected to a miniature sandbox experimental platform and is used to execute a forward collision warning system key parameter verification method based on a miniature sandbox experimental platform as described in any one of claims 1 to 7.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the key parameter verification method of the forward collision warning system based on the miniature sandbox experimental platform as described in any one of claims 1 to 7 is implemented.

Images