Dirt detection method and apparatus, vehicle, and storage medium

Abstract

The embodiment of the application provides a kind of dirty detection method, device, vehicle and storage medium, the method is applied to vehicle, the vehicle is equipped with at least one laser radar, the method comprises: obtaining the first echo signal of laser radar in target detection period;Determine whether target detection period is abnormal detection period based on the signal strength of first echo signal;In the case where the number of continuous abnormal detection periods is greater than or equal to the preset number, determine that dirty event occurs, wherein, dirty event refers to the event that the surface of the light-transmitting cover plate of laser radar away from laser emitting device appears dirty.The embodiment of the application provides a kind of dirty detection measure for laser radar, can detect whether the surface of laser radar exists dirty in time, and then propose corresponding processing measures, such as reminding user to wipe, can guarantee that laser radar works under higher working performance, improve driving safety.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser radar, and more particularly, to a dirt detection method and device, a vehicle, and a storage medium. BACKGROUND

[0002] A laser radar is a radar system that detects the position, speed, and other characteristic quantities of a target by emitting a laser beam. In the automotive field, a laser radar is usually arranged on both sides of the front of a vehicle to detect obstacles in front of the vehicle.

[0003] A laser radar includes a laser emitting device, a laser receiving device, and a light-transmitting cover plate arranged in the emission path of the laser emitting device. When the light-transmitting cover plate is dirty (e.g., with insects, ice, snow, or sludge), the range of the laser radar will decrease. To ensure normal operation of the laser radar, it is necessary to detect whether the light-transmitting cover plate of the laser radar is dirty in a timely manner and to remind the user to clean the dirt in a timely manner when the light-transmitting cover plate is dirty.

[0004] The related art does not provide a technical solution for detecting whether the light-transmitting cover plate of a laser radar is dirty. SUMMARY

[0005] The present application provides a dirt detection method, device, vehicle, and storage medium.

[0006] In a first aspect, the present application provides a dirt detection method applied to a processor of a vehicle, the vehicle being provided with at least one laser radar, the laser radar including a laser emitting device and a light-transmitting cover plate arranged on the emission side of the laser emitting device. The method includes: acquiring a first echo signal of the laser radar in a target detection period, the first echo signal being a reflected echo signal of a laser beam emitted by the laser emitting device via the light-transmitting cover plate; determining whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal; and determining that a dirt event occurs when the number of consecutive abnormal detection periods is greater than or equal to a preset number, wherein the dirt event refers to an event in which the surface of the light-transmitting cover plate of the laser radar away from the laser emitting device is dirty.

[0007] In a second aspect, the embodiments of the present application provide a dirt detection device, which is applied to a vehicle, the vehicle is provided with at least one laser radar, the laser radar comprises a laser emitting device and a light-transmitting cover plate arranged on the emitting side of the laser emitting device, and the device comprises: a signal acquisition module, configured to acquire a first echo signal of the laser radar in a target detection period; a period detection module, configured to determine whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal; and an event detection module, configured to determine that a dirt event occurs in the case that the number of continuous abnormal detection periods is greater than or equal to a preset number, wherein the dirt event refers to an event that the surface of the light-transmitting cover plate of the laser radar away from the laser emitting device is dirty.

[0008] In a third aspect, the embodiments of the present application provide a vehicle, which comprises a processor, a memory and at least one laser radar, the memory stores computer program instructions, and the computer program instructions are called and executed by the processor to perform the dirt detection method of the first aspect.

[0009] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, which stores program codes, and the program codes are called and executed by a processor to perform the dirt detection method of the first aspect.

[0010] In a fifth aspect, the embodiments of the present application provide a computer program product, which, when executed, can implement the dirt detection method of the first aspect.

[0011] The embodiments of the present application provide a dirt detection method, which determines whether a target detection period is an abnormal detection period based on the signal strength of a first echo signal in the target detection period, and then determines whether a dirt event occurs according to the number of continuous abnormal detection periods. Since the reflectivity of a laser beam is greater when there is dirt on the light-transmitting cover plate than when there is no dirt on the light-transmitting cover plate, the signal strength of the first echo signal of the laser beam reflected by the light-transmitting cover plate is usually greater when there is dirt on the light-transmitting cover plate than when there is no dirt on the light-transmitting cover plate. Therefore, through the above detection steps, a dirt event can be detected in time, so that subsequent corresponding processing measures can be taken, so that the working performance of the laser radar can always remain at a high level, and thus the driving safety can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0013] Figure 1 is a working principle diagram of a laser radar provided by an embodiment of the present application.

[0014] Figure 2 is a schematic diagram of an implementation environment provided by an embodiment of the present application.

[0015] Figure 3 is a flowchart of a dirty detection method provided by an embodiment of the present application.

[0016] Figure 4 is an interface schematic diagram of a reminder information provided by an embodiment of the present application.

[0017] Figure 5 is a flowchart of a dirty detection method provided by another embodiment of the present application.

[0018] Figure 6 is a flowchart of a dirty detection method provided by another embodiment of the present application.

[0019] Figure 7 is a flowchart of a dirty detection method provided by another embodiment of the present application.

[0020] Figure 8 is a block diagram of a dirty detection device provided by an embodiment of the present application.

[0021] Figure 9 is a structural diagram of a vehicle provided by an embodiment of the present application.

[0022] Figure 10 is a structural block diagram of a computer readable storage medium provided by an embodiment of the present application. DETAILED DESCRIPTION

[0023] The embodiments of the present application are described in detail below, examples of the embodiments are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0024] In order to make the person skilled in the art better understand the scheme of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor are within the scope of protection of the present application.

[0025] First, the working principle of the laser radar is introduced.

[0026] The laser radar 10 comprises a laser emitting device 11, a laser receiving device 12, a light-transmitting cover plate 13, and a micro processing unit 14. The light-transmitting cover plate 13 is arranged opposite to the laser emitting device 11 and is located on the light path of the laser beam emitted by the laser emitting device 11, i.e. the laser beam emitted by the laser emitting device 11 needs to pass through the light-transmitting cover plate 13. The micro processing unit 14 is electrically connected to the laser emitting device 11 and the laser receiving device 12 respectively.

[0027] Step 10: The laser emitting device 11 emits a laser beam.

[0028] Step 11: When the laser beam hits the light-transmitting cover plate 13, a first echo signal is generated.

[0029] Step 12: The laser receiving device 12 receives the first echo signal T0.

[0030] Step 13: The laser receiving device 12 sends the parameters of the first echo signal T0 to the micro processing unit 14.

[0031] The parameters of the first echo signal T0 include signal strength, receiving time stamp, etc.

[0032] Step 14: When the laser beam hits an obstacle, a second echo signal T1 is generated.

[0033] Step 15: The laser receiving device 12 receives the second echo signal T1.

[0034] Step 16: The laser receiving device 12 sends the parameters of the second echo signal T1 to the micro processing unit 14.

[0035] The parameters of the second echo signal T0 include signal strength, receiving time stamp, etc.

[0036] Step 17: The micro processing unit 14 determines the distance, shape, etc. between the obstacle and the vehicle based on the parameters of the second echo signal T1.

[0037] For example, the micro processing unit 14 obtains the emission time stamp t1 of the laser beam and the receiving time stamp t2 of the second echo signal T1, and then the distance d between the vehicle and the obstacle is calculated as d = (t2-t1)*v / 2, where v is the speed of light.

[0038] Referring to Figure 2 , a schematic diagram of an implementation environment provided by an embodiment of the present application is shown. Referring to Figure 2 , a schematic diagram of an implementation environment provided by an embodiment of the present application is shown. The implementation environment is a vehicle 200. The vehicle 200 can be a car, an airplane, etc., and the embodiments of the present application do not limit the vehicle 200.

[0039] The vehicle 200 is provided with at least one laser radar 210, a processor. A communication connection is established between the laser radar 210 and the processor. The laser radar 200 is used to detect whether there is an obstacle in front of the vehicle 200 and the related parameters of the obstacle, and its working principle is as follows: the laser radar emits a plurality of laser beams at the same time, if there is an obstacle in front of the vehicle 200 (in the detection range of the laser radar 210), the laser beam will be reflected after passing through the obstacle, the laser radar 210 receives the reflected laser beam, and based on the received laser beam and the emitted laser beam, the distance, direction, height, speed, attitude, shape and other parameters of the obstacle are determined. In the embodiment of the application, the vehicle 200 is provided with two laser radars 210, which are respectively located on both sides of the vehicle head position.

[0040] The laser radar 210 includes a laser emitting device, a laser receiving device, and a light-transmitting cover plate opposite the laser emitting device. When the light-transmitting cover plate of the laser radar 210 is dirty, such as flying insects, ice and snow, sludge and the like, the range of the laser radar 210 will decrease, that is, the working performance of the laser radar 210 will decrease, so it is necessary to provide a detection measure for the dirt on the laser radar 210, so that the user can discover and handle the dirt on the laser radar 210 in time, and ensure the working performance of the laser radar 210.

[0041] Because the reflectivity of the laser beam on the light-transmitting cover plate with dirt is greater than the reflectivity of the laser beam on the light-transmitting cover plate without dirt, therefore the signal strength of the first echo signal of the laser beam reflected by the light-transmitting cover plate with dirt is usually greater than the signal strength of the first echo signal of the laser beam reflected by the light-transmitting cover plate without dirt, therefore the application provides a detection measure for the dirt event, by the signal strength of the first echo signal of the laser radar in a detection period to determine whether the detection period is an abnormal detection period, in the case of multiple continuous abnormal detection periods, it is determined that a dirt event occurs, so that the vehicle 200 can detect the dirt event in time, so as to take corresponding processing measures subsequently, so that the working performance of the laser radar 210 always remains at a high level, and thus the driving safety is ensured.

[0042] In some embodiments, the vehicle 200 further comprises a display device for displaying the reminding information, which can be an in-vehicle infotainment (IVI). The display device can be arranged at the side of the dashboard of the vehicle 200, so that the user can also check the reminding information through the display device when controlling the vehicle 200 to drive. In other possible implementations, the vehicle 200 further comprises a voice interaction device for playing the reminding information in the form of voice. The voice interaction device can be a loudspeaker.

[0043] The execution subject of each step can be a processor in the vehicle 200 or the lidar 210, which is not limited in the embodiments of the present application. In the embodiments of the present application, only the execution subject of each step is taken as the vehicle 200 for illustration.

[0044] Figure 3 is a flowchart of the dirty detection method provided by an embodiment of the present application. The method comprises:

[0045] In step 301, the first echo signal of the lidar in a target detection period is acquired.

[0046] The target detection period can be any detection period. Exemplarily, the target detection period is the detection period closest to the current time.

[0047] The first echo signal is the echo signal reflected after the laser beam emitted by the lidar hits the light-transmitting cover plate. In some embodiments, after the lidar receives the echo signal, it is judged whether the receiving timestamp of the echo signal is within a preset time range. If yes, it is considered that the echo signal is the first echo signal, and if no, it is considered that the echo signal is not the first echo signal.

[0048] The preset time range is a time range with the laser emission timestamp of the target detection period as the starting point and a preset length as the time length. The preset length is set according to experiments or experience. For example, if the duration of the target detection period is 10 seconds, the preset length can be any value within 1 to 6. Exemplarily, the preset length is 5 seconds. In an example, in a test environment, the lidar emits a laser beam at a certain time, and the first echo signal of the laser beam is received by the lidar at the time after the emission. The lidar records the receiving time of the first echo signal of each laser beam, and then sets the time interval between the receiving time of the last received first echo signal and the emission time as the preset length.

[0049] In some embodiments, the laser radar acquires the first echo signal after power-on and starts the subsequent dirt detection process. In other embodiments, the laser radar acquires the first echo signal when a range drop event is detected and starts the subsequent dirt detection process. The range drop event refers to an event in which the ratio between the actual range of the laser radar and the calibrated range is less than a third preset percentage. In yet other embodiments, the laser radar acquires the first echo signal when no occlusion event is detected and starts the subsequent dirt detection process. The occlusion event refers to an event in which the surface of the light-transmitting cover away from the laser emitting device is covered with a target object. In still other embodiments, the laser radar detects whether an occlusion event occurs when a range drop event is detected, acquires the first echo signal when no occlusion event is detected, and starts the subsequent dirt detection process.

[0050] The detection process of the range drop event and the occlusion event will be described in the following embodiments. By setting the starting event of the dirt detection process in the above manner, the laser radar can avoid performing unnecessary dirt detection processes, thereby saving processing resources.

[0051] In step 302, it is determined whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal.

[0052] The target detection period refers to a detection period in which the ratio between the number of abnormal first echo signals and the total number of laser beams is greater than a first preset percentage. The abnormal first echo signal refers to a first echo signal in which the ratio between the actual intensity and the calibrated intensity is greater than a preset value.

[0053] Since the reflectivity of the laser beam on the light-transmitting cover with dirt is greater than the reflectivity of the laser beam on the light-transmitting cover without dirt, the signal strength of the first echo signal reflected by the laser beam on the light-transmitting cover with dirt is generally greater than the signal strength of the first echo signal reflected by the laser beam on the light-transmitting cover without dirt. Based on the above principle, the embodiments of the present application can determine whether the target detection period is an abnormal detection period by the signal strength of the first echo signal in the target detection period, determine that a dirt event occurs when there are multiple consecutive abnormal detection periods, and enable the vehicle to detect the dirt event in a timely manner, so that subsequent appropriate processing measures can be taken, so that the working performance of the laser radar can always remain at a high level, thereby ensuring driving safety.

[0054] In some embodiments, step 302 can include the following sub-steps:

[0055] In step 302a, it is determined whether the first echo signal is an abnormal first echo signal based on the signal strength of the first echo signal.

[0056] Optionally, the laser radar obtains a first ratio between the signal strength of the first echo signal and the calibration strength; and in a case where the first ratio is greater than a preset value, the first echo signal is determined as an abnormal first echo signal.

[0057] The calibration strength is obtained through testing. In a testing environment, there is no dirt on the light-transmitting cover plate of the laser radar, the laser radar emits a laser beam at a certain time, and the first echo signal of the laser beam is received by the laser radar for the first time after the emission time. The laser radar records the signal strength of each first echo signal, and then determines the calibration strength under the non-dirty condition based on the signal strength of each first echo signal. In one example, the laser radar determines the mean value of the signal strength of each first echo signal as the calibration strength.

[0058] The preset value is set according to experiments or experience. For another example, in a testing environment, there is dirt on the light-transmitting cover plate of the laser radar, the laser radar emits a laser beam at a certain time, and the first echo signal of the laser beam is received by the laser radar for the first time after the emission time. The laser radar records the signal strength of each first echo signal, and then determines the calibration strength under the dirty condition based on the signal strength of each first echo signal. In one example, the laser radar determines the minimum value of the signal strength of each first echo signal as the calibration strength under the dirty condition. Then, the ratio of the calibration strength under the dirty condition to the calibration strength under the non-dirty condition is determined as the preset value. For example, the preset value can be any value between 1.5 and 5. Exemplarily, the preset value is 2.

[0059] Exemplarily, the signal strength of the first echo signal received by the laser radar is 500, the calibration strength is 200, and the preset value is 2. The ratio between the signal strength of the above first echo signal and the calibration strength is 2.5, which is greater than the preset value, so the first echo signal is an abnormal first echo signal.

[0060] Step 302b, based on the number of abnormal first echo signals, determining whether the target detection period is an abnormal detection period.

[0061] Optionally, the laser radar obtains a second ratio between the number of abnormal first echo signals and the total number of laser beams in the target detection period; and in a case where the second ratio is greater than or equal to a first preset percentage, the target detection period is determined as an abnormal detection period.

[0062] The first preset percentage is set according to experiments or experience. For example, the first preset percentage can be any value between 50% and 90%. For example, the first preset percentage is 60%. For example, the number of abnormal first echo signals of the laser radar in the target detection period is 72, and the total number of laser beams in the target detection period is 100, and the second ratio is 72%, which is greater than the first preset percentage, so the target detection period is an abnormal detection period.

[0063] In step 303, when the number of continuous abnormal detection periods is greater than or equal to a preset number, it is determined that a dirty event occurs.

[0064] The preset number is set according to experiments or experience. For example, the preset number can be any value between 4 and 10. For example, the preset number is 6. The dirty event refers to the event that the surface of the light-transmitting cover plate of the laser radar away from the laser emitting device is dirty.

[0065] In some embodiments, after detecting that a dirty event occurs, the laser radar sends a notification message to the processor, and the processor issues a reminder information according to the notification message to remind the user to clean the dirt on the surface of the light-transmitting cover plate of the laser radar away from the laser emitting device in time, thereby reducing the impact on the range of the laser radar. The reminder information can be voice information, which is played by the processor controlling the loudspeaker. The reminder information can also be text information, which is displayed by the processor controlling the display device. Reference Figure 4 Fig. 4 shows an interface schematic diagram of the reminder information provided by an embodiment of the present application. The display device in the vehicle displays the reminder information 41 "Radar is dirty, please wipe".

[0066] In summary, the dirty detection method provided by the embodiments of the present application determines whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal in the target detection period, and then determines whether a dirty event occurs according to the number of continuous abnormal detection periods. Since the reflectivity of the laser beam on the light-transmitting cover plate with dirt is greater than the reflectivity of the laser beam on the light-transmitting cover plate without dirt, the signal strength of the first echo signal of the laser beam reflected by the light-transmitting cover plate with dirt is usually greater than the signal strength of the first echo signal of the laser beam reflected by the light-transmitting cover plate without dirt. Therefore, through the above detection steps, the dirty event can be detected in time, so that subsequent appropriate processing measures can be taken to keep the working performance of the laser radar at a high level, thereby ensuring driving safety.

[0067] Figure 5 Fig. 3 shows a flow chart of detection of an abnormal detection period provided by another embodiment of the present application. The detection flow of the abnormal detection period includes the following steps:

[0068] Step 501, set the initial value of the first counter and the second counter as 0.

[0069] The first counter is used to count the number of dirty points, and the first counter is set to 0, i.e. t0_dirty_num = 0. The second counter is used to count the number of points traversed, and the second counter is set to 0, i.e. total_point_num = 0.

[0070] Step 502, receive the echo signal.

[0071] The laser receiving device receives the echo signal.

[0072] Step 503, detect whether the echo signal is the first echo signal.

[0073] Since the light-transmitting cover plate is closer to the laser emitting device than the obstacle, the time at which the laser receiving device receives the first echo signal T0 should be less than the time at which the laser receiving device receives the second echo signal T5.

[0074] The micro-processing unit detects whether the echo signal is the first echo signal based on the difference between the reception event stamp of the echo signal and the emission time stamp of the laser beam. If the difference is less than a first preset difference, it means that the echo signal is the first echo signal. If the difference is greater than the first preset difference and less than a second preset difference, it means that the echo signal is the second echo signal.

[0075] If yes, step 504 is executed. If no, no processing is performed.

[0076] Step 504, add 5 to the value of the second counter.

[0077] Step 505, detect whether the ratio between the actual intensity and the calibrated intensity of the echo signal is greater than a preset value.

[0078] The preset value is used to determine whether the first echo signal T0 is an abnormal first echo signal. If the ratio between the actual intensity and the calibrated intensity of the first echo signal T0 is greater than the preset value, it means that the first echo signal T0 is an abnormal first echo signal.

[0079] If yes, step 502 is executed.

[0080] Step 506, add 1 to the value of the first counter.

[0081] Step 507, detect whether the value of the second counter is greater than the total number of laser beams.

[0082] If yes, step 508 is executed. If no, the execution starts again from step 505.

[0083] Step 508, calculate the dirt point rate according to the value of the first counter.

[0084] The micro-processing unit determines the ratio between the value of the first counter and the total number of laser beams as the dirt point rate. For example, the value of the first counter is 56, and the total number of laser beams is 100, then the dirt point rate is 56%.

[0085] Step 509, detect whether the dirt point rate is greater than a first preset percentage.

[0086] If yes, execute step 510, if not, execute step 511.

[0087] Step 510, determine the target detection period as an abnormal detection period.

[0088] Step 511, determine the target detection period as a normal detection period.

[0089] Figure 6 is a flowchart of a dirt detection method provided by another embodiment of the present application. The method comprises:

[0090] Step 601, in the case where a range drop event of the laser radar is detected, detect whether a blocking event of the laser radar occurs.

[0091] The range drop event refers to an event in which the ratio between the actual range of the laser radar and the calibrated range is less than a third preset percentage. The calibrated range is obtained through testing. In one example, in a test environment, an obstacle (such as a black vehicle or a pedestrian wearing a black clothes) is arranged in front of the vehicle, the distance between the obstacle and the vehicle is gradually increased until the detection rate of the laser radar on the obstacle is the preset detection rate threshold, at this time, the distance between the obstacle and the vehicle is set as the calibrated range. The third preset percentage is set according to experiments or experience, which can be any value between 50% and 90%, for example, the third preset percentage is 70%.

[0092] Optionally, when the laser radar detects a certain obstacle, if the detection rate is less than the preset detection rate threshold, the distance between the obstacle and the vehicle is determined as the actual range of the laser radar. The detection rate refers to the ratio between the number of secondary echo signals reflected by the obstacle and the total number of laser beams. The preset detection rate threshold is set according to experiments or experience, for example, the preset detection rate threshold is 50%.

[0093] An occlusion event refers to an event that the surface of the transparent cover plate facing away from the laser emitting device is covered by a target object. The target object refers to an object with reflectivity greater than a preset reflectivity, such as a plastic bag, paper, and the like. Since the reflectivity of the target object is very large, the laser beam cannot be projected to the obstacle through the target object, and at this time the range of the lidar is almost zero. The process of detecting whether an occlusion event occurs includes the following steps:

[0094] Step 601a, obtaining the number of secondary echo signals received in the target detection period.

[0095] The secondary echo signal refers to the echo signal reflected by the laser beam emitted by the laser emitting device through the obstacle. In some embodiments, after the lidar receives the echo signal, it is judged whether the receiving time stamp of the echo signal is within a preset time range. If not, the echo signal is a secondary echo signal.

[0096] Step 601b, obtaining a third ratio between the difference between the total number of laser beams in the target detection period and the number of secondary echo signals, and the total number of laser beams in the target detection period.

[0097] In the case that the surface of the transparent cover plate facing away from the laser emitting device is covered by a target object, the laser beam cannot be projected to the obstacle through the target object, and at this time the lidar cannot receive the secondary echo signal reflected by the obstacle. Therefore, whether the lidar is blocked by a large area can be determined based on the number of laser beams for which no secondary echo signal is received. The above-mentioned third ratio can be referred to as an occlusion rate. For example, the total number of laser beams in the target detection period is 100, and the number of received secondary echo signals is 30, then the third ratio is (100-30) / 100=70%.

[0098] Step 601c, determining that an occlusion event occurs when the third ratio is greater than or equal to a second preset percentage.

[0099] The second preset percentage is set according to experiments or experience, which can be any value between 50% and 90%. Exemplarily, the second preset percentage is 65%.

[0100] Step 602, obtaining the first echo signal of the lidar in the target detection period when the lidar does not occur an occlusion event.

[0101] The first echo signal refers to the echo signal reflected by the laser beam emitted by the laser emitting device through the transparent cover plate.

[0102] Step 603, determining whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal.

[0103] Step 604, in the case that the number of continuous abnormal detection periods is greater than or equal to the preset number, it is determined that a dirty event occurs.

[0104] The dirty event refers to an event that dirt appears on the surface of the light-transmitting cover plate away from the laser emitting device.

[0105] In summary, the technical scheme provided by the embodiments of the present application can avoid unnecessary dirty detection process by performing the subsequent dirty detection process when the range drop event is detected and no shielding event is detected, thereby saving processing resources.

[0106] It should be noted that the laser radar may also cause the range to drop due to other factors, such as heavy rain, the laser radar being blocked by an obstacle within a short distance (such as 50 cm), the light-transmitting cover plate of the laser radar having cracks or pits due to stone impact, water mist appearing on the side of the light-transmitting cover plate facing the laser emitting device, and the like. Since the above factors are human factors that cannot be eliminated, the user does not need to be reminded. Therefore, the dirty detection method provided by the embodiments of the present application also needs to exclude the range drop caused by other factors based on the working parameters of the vehicle or the functional components included in the vehicle. The embodiments of the present application also provide a dirty detection method, which includes the following steps:

[0107] Step 701, acquiring the first echo signal of the laser radar in the target detection period.

[0108] Step 702, determining whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal.

[0109] Step 703, in the case that the number of continuous abnormal detection periods is greater than or equal to the preset number, acquiring the working parameters of the vehicle.

[0110] The working parameters include at least one of the following: a speed parameter of the vehicle, a temperature parameter of the vehicle, and a working gear of a windshield wiper of the vehicle.

[0111] The speed parameter of the vehicle is used to indicate the driving speed of the vehicle.

[0112] The temperature parameter of the vehicle includes a first temperature parameter and a second temperature parameter. The first temperature parameter represents the ambient temperature of the vehicle, which can be measured by a temperature sensor arranged on the surface of the vehicle, or obtained from the cloud by the processor of the vehicle. The second temperature parameter represents the internal temperature of the laser radar. Optionally, a temperature sensor is arranged in the closed space on the side of the light-transmitting cover plate of the laser radar facing the laser emitting device, and the second temperature parameter is measured by the temperature sensor.

[0113] The working gear of the wiper of the vehicle represents the moving speed of the wiper. The vehicle also includes a wiper, which also has a communication connection, such as an I2C connection, with the processor. The wiper is an important accessory installed on the windshield of the vehicle 300, which is used to sweep away the rain, snow and dust on the windshield that obstructs the view. Generally, the wiper is provided with different gears, and the higher the gear, the faster the moving speed of the wiper, and the more rapid the sweeping of obstacles, so the higher the gear of the wiper when the rain is heavy. In the embodiments of the present application, the wiper sends the gear information of the wiper to the processor. In some embodiments, the wiper reports the working gear of the wiper to the processor at a preset time interval. In other embodiments, the processor sends a query instruction to the wiper when the dirt detection result meets the preset condition, and the wiper reports the working gear of the wiper to the processor based on the query instruction.

[0114] In step 704, the driving scene of the vehicle is determined based on the working parameter of the vehicle.

[0115] When the working parameter of the vehicle includes the working gear of the wiper, step 704 is specifically implemented as follows: when the working gear of the wiper is a preset gear, it is determined that the driving scene of the vehicle is a heavy rain scene. When the working gear of the wiper is not the preset gear, it is determined that the driving scene of the vehicle is not the heavy rain scene.

[0116] The working gear represents the speed parameter of the wiper. The preset gear has a higher speed parameter than the non-preset gear. In some examples, the working gear of the wiper includes low gear, medium gear and high gear. The speed parameter corresponding to the high gear is the highest, and the speed parameter corresponding to the low gear is the lowest. The preset gear is the high gear, that is, when the working gear of the wiper is the high gear, it is determined that the driving scene of the vehicle is the heavy rain scene. In other examples, the working gear of the wiper is represented by a number, such as gear 1, gear 2, gear 3, gear 4, and the like, and the speed parameter corresponding to gear 1 is the highest, and the speed parameter corresponding to gear 2 is the lowest. The preset gear is gear 1 and gear 2, that is, when the working gear of the wiper is gear 1 or gear 2, it is determined that the driving scene of the vehicle is the heavy rain scene.

[0117] When the working parameter of the vehicle includes the temperature parameter, step 704 is implemented as follows: when the temperature difference between the first temperature parameter and the second temperature parameter is greater than a preset difference, the heat generating material covering the surface of the laser radar is controlled to generate heat; after the heat generation time is greater than or equal to a preset time, the dirt detection result is reacquired; when the reacquired dirt detection result does not meet the preset condition, it is determined that the driving scene of the vehicle is the internal fogging scene; when the reacquired dirt detection result meets the preset condition, it is determined that the driving scene of the vehicle is not the internal fogging scene.

[0118] The vehicle further comprises a heating circuit and a heating control circuit. The processor is in communication connection with the heating control circuit and the temperature sensor. The heating control circuit is electrically connected with the heating circuit. The heating control circuit is configured to control the heating circuit to be turned on. The heating circuit comprises a heating material, such as a heating film, disposed on the light-transmitting cover plate of the laser radar, and the heating material has the characteristics of electrical conductivity and high electrical conductivity. When the heating circuit is turned on, the heating material generates heat to evaporate the water mist on the light-transmitting cover plate of the laser radar.

[0119] The preset time length can be set according to experiments or experience. For example, the preset time length can be any value between 2 and 15. For example, the preset time length is 3 minutes, that is, the heating circuit is controlled to be in the turned-on state for 3 minutes. The process of reacquiring the dirty detection result can refer to the process of acquiring the dirty detection result. Figure 3 In an embodiment, the preset condition refers to that the detection period of the laser radar after heating is not an abnormal detection period. In the internal fogging scenario, if the heating material generates heat, the water mist on the laser radar can be evaporated. At this time, when dirty detection is performed again, the number of abnormal first echo signals is greatly reduced. Therefore, whether the driving scenario of the vehicle is the internal fogging scenario can be determined according to the dirty detection result after heating. If the dirty detection result after heating indicates that the number of abnormal first echo signals received by the laser radar is reduced and there is no abnormal detection period, it is determined that the driving scenario is the internal fogging scenario.

[0120] When the working parameter of the vehicle comprises a speed parameter of the vehicle, step 704 is implemented as follows: in a case where the speed parameter of the vehicle is less than a preset speed, it is determined that the driving scenario of the vehicle is a low-speed driving scenario; and in a case where the driving speed of the vehicle is greater than the preset speed, it is determined that the driving scenario of the vehicle is a high-speed driving scenario. The preset speed can be set according to actual needs, and the embodiment of the present application does not limit the preset speed. For example, the preset speed can be any value between 5 and 25. For example, the preset speed is 20 km / h.

[0121] In step 705, it is determined that the dirty event occurs in a case where the working scenario of the vehicle is not the preset scenario.

[0122] The preset scenario comprises at least one of the following: a heavy rain scenario, a low-speed driving scenario, and an internal fogging scenario. In the embodiment of the present application, before it is determined whether the dirty event occurs, it is determined that the driving scenario of the vehicle, so as to exclude the range reduction of the laser radar caused by other factors (such as rain blocking, water mist on the side of the light-transmitting cover plate of the laser radar facing the laser emitting device, and obstacles appearing at a close distance from the laser radar), and then it is determined whether the dirty event occurs.

[0123] It should be noted that the processor can sequentially detect whether the driving scene of the vehicle is a low-speed driving scene, a rainstorm scene, and an internal fogging scene, and determine that the dirty event occurs in a case where the driving scene of the vehicle is not any of the above three scenes. It should be noted that the embodiments of the present application do not limit the detection order of whether it is any of the above three scenes. In addition, it should be noted that the processor does not need to perform the subsequent judgment step after determining that the driving scene of the vehicle is any of the above preset scenes. For example, in a case where it is determined that the driving scene of the vehicle is a low-speed driving scene, it is not necessary to continue to judge whether it is in a rainstorm scene or an internal fogging scene.

[0124] In summary, the dirty detection method provided by the embodiments of the present application determines the driving scene of the vehicle before determining whether the dirty event occurs, so as to exclude the range decrease of the laser radar caused by other factors (such as rain shielding, water mist on the side of the light-transmitting cover plate of the laser radar facing the laser emitting device, and obstacles appearing at a close distance of the laser radar), and thus the dirty event can be accurately determined.

[0125] Please refer to Figure 8 which shows a structural block diagram of a dirty detection device 800 provided by an embodiment of the present application. The device is applied to a vehicle, and the vehicle is provided with at least one laser radar, and the laser radar includes a laser emitting device and a light-transmitting cover plate arranged on the emitting side of the laser emitting device. The device 800 includes a signal acquisition module 810, a period detection module 820, and an event detection module 830. The signal acquisition module 810 is configured to acquire a first echo signal of the laser radar in a target detection period, and the first echo signal refers to an echo signal of a laser beam emitted by the laser emitting device and reflected via the light-transmitting cover plate. The period detection module 820 is configured to determine whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal. The event detection module 830 is configured to determine that a dirty event occurs in a case where the number of continuous abnormal detection periods is greater than or equal to a preset number, and the dirty event refers to an event that the surface of the light-transmitting cover plate of the laser radar deviates from the laser emitting device and appears dirty.

[0126] In summary, the dirt detection device provided in this application determines whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal within the target detection period. Then, it determines whether a dirt event has occurred based on the number of consecutive abnormal detection periods. Since the reflectivity of the laser beam is greater when there is dirt on the cover plate than when there is no dirt, the signal strength of the first echo signal of the laser beam reflected by the cover plate when there is dirt is usually greater than the signal strength of the first echo signal of the laser beam reflected by the cover plate when there is no dirt. Therefore, through the above detection steps, dirt events can be detected in a timely manner so that corresponding processing measures can be taken subsequently, ensuring that the performance of the lidar remains at a high level and thus guaranteeing driving safety.

[0127] In some embodiments, the period detection module 820 is used to determine whether the first echo signal is an abnormal first echo signal based on the signal strength of the first echo signal; and to determine whether the target detection period is an abnormal detection period based on the number of abnormal first echo signals.

[0128] In some embodiments, the period detection module 820 is used to obtain a first ratio between the signal strength of the first echo signal and the calibration strength; if the first ratio is greater than a preset value, the first echo signal is determined to be an abnormal first echo signal.

[0129] In some embodiments, the period detection module 820 is used to obtain a second ratio between the number of abnormal first echo signals and the total number of laser beams within the target detection period; if the second ratio is greater than or equal to a preset percentage, the target detection period is determined to be an abnormal detection period.

[0130] In some embodiments, the device further includes a first detection module ( Figure 8 (Not shown). The first detection module is used to detect whether an obstruction event has occurred with the lidar. An obstruction event refers to an event where a target object is covered by a light-transmitting cover plate that is away from the surface of the laser emitting device. The signal acquisition module 810 is also used to perform the step of acquiring the first echo signal of the lidar during the target detection period if no obstruction event has occurred with the lidar.

[0131] In some embodiments, the first detection module is used to obtain the number of secondary echo signals received within the target detection period, wherein the secondary echo signal refers to the echo signal reflected by the laser beam emitted by the laser emitting device through the obstacle; obtain the difference between the total number of laser beams and the number of secondary echo signals within the target detection period, and a third ratio between the difference and the total number of laser beams within the target detection period; and determine that an occlusion event has occurred if the third ratio is greater than or equal to a second preset percentage.

[0132] In some embodiments, the signal acquisition module 810 is further configured to, in a case where it is detected that the laser radar has a range drop event, perform the step of acquiring the first echo signal of the laser radar in a target detection period, the range drop event being an event in which a ratio between an actual range of the laser radar and a calibrated range is less than a third preset percentage.

[0133] As shown in Figure 9 The examples of the present application also provide a vehicle 900, which includes a processor 910, a memory 920, and a laser radar 930. The memory 920 stores computer program instructions.

[0134] The processor 910 can include one or more processing cores. The processor 910 connects various parts within the battery management system through various interfaces and lines, and performs various functions of the battery management system and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 920, and calling data stored in the memory 920. Alternatively, the processor 910 can be implemented in at least one of a hardware form of a digital signal processing (DSP), a field-programmable gate array (FPGA), and a programmable logic array (PLA). The processor 910 can be integrated with a combination of one or more of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. Among them, the CPU is mainly used to process operating systems, user interfaces, and application programs; the GPU is used to render and draw display content; and the modem is used to process wireless communication. It can be understood that the above-mentioned modem can also not be integrated into the processor 910, but can be realized by a separate communication chip.

[0135] The memory 920 can include a random access memory (RAM) and can also include a read-only memory (ROM). The memory 920 can be used to store instructions, programs, codes, code sets, or instruction sets. The memory 920 can include a program storage area and a data storage area, where the program storage area can store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playing function, an image playing function, etc.), instructions for implementing various method examples described below, etc. The data storage area can also store data created by the vehicle in use (such as a phone book, audio and video data, chat record data, etc.).

[0136] Referring to Figure 10 It is shown that the embodiments of the present application further provide a computer readable storage medium 1000, which stores computer program instructions 1010. The computer program instructions 1010 can be invoked by a processor to execute the methods described in the above embodiments.

[0137] The computer readable storage medium 1000 can be an electronic storage such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk, or a ROM. Alternatively, the computer readable storage medium 1000 includes a non-volatile computer readable storage medium. The computer readable storage medium 1000 has a storage space for the computer program instructions 1010 to execute any of the method steps described above. These computer program instructions 1010 can be read from or written into one or more computer program products. The computer program instructions 1010 can be compressed in an appropriate form.

[0138] The above is only a preferred example of the present application, and does not limit the present application in any form. Although the present application has been disclosed as the above preferred example, it is not intended to limit the present application. Any person skilled in the art can make slight changes or modifications to the above disclosed technical content to obtain equivalent examples without departing from the scope of the technical solutions of the present application. Any modification, change, and modification of the above examples according to the technical essence of the present application, as long as it does not deviate from the technical solutions of the present application, is still within the scope of the technical solutions of the present application.

Claims

1. A method for detecting dirt and grime, characterized in that, The method is applied to a vehicle equipped with at least one lidar, the lidar including a laser emitting device and a light-transmitting cover disposed on the emitting side of the laser emitting device, the method comprising: When a range reduction event is detected in the lidar, the first echo signal of the lidar within the target detection period is acquired. The first echo signal refers to the echo signal reflected by the laser beam emitted by the laser emitting device through the light-transmitting cover plate. The range reduction event refers to an event in which the ratio between the actual range and the calibrated range of the lidar is less than a third preset percentage. Based on the signal strength of the first echo signal, determine whether the target detection period is an abnormal detection period; If the number of consecutive abnormal detection cycles is greater than or equal to a preset number, a dirt event is determined to have occurred. The dirt event refers to an event in which dirt appears on the surface of the light-transmitting cover that is away from the laser emitting device. The method further includes: if the detection rate of the obstacle detected by the lidar is less than a preset detection rate threshold, then the distance between the obstacle and the vehicle is determined as the actual range of the lidar; and if the ratio between the actual range of the lidar and the calibrated range is less than a third preset percentage, then the range reduction event is determined to have occurred.

2. The method according to claim 1, characterized in that, Determining whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal includes: Based on the signal strength of the first echo signal, determine whether the first echo signal is an abnormal first echo signal; Based on the number of the first abnormal echo signals, determine whether the target detection period is the abnormal detection period.

3. The method according to claim 2, characterized in that, Determining whether the first echo signal is an abnormal first echo signal based on the signal strength of the first echo signal includes: Obtain a first ratio between the signal strength of the first echo signal and the calibration strength; If the first ratio is greater than a preset value, the first echo signal is determined to be the abnormal first echo signal.

4. The method according to claim 2, characterized in that, Determining whether the target detection period is the anomaly detection period based on the number of the first abnormal echo signals includes: Obtain a second ratio between the number of abnormal first echo signals and the total number of laser beams within the target detection period; If the second ratio is greater than or equal to the first preset percentage, the target detection period is determined to be the anomaly detection period.

5. The method according to any one of claims 1 to 4, characterized in that, Before acquiring the first echo signal of the lidar during the target detection period, the process also includes: If the range of the lidar does not decrease, the lidar is checked for an obstruction event. The obstruction event refers to an event in which the surface of the light-transmitting cover away from the laser emitting device is covered by a target object. If the occlusion event does not occur with the lidar, the step of acquiring the first echo signal of the lidar during the target detection period is performed.

6. The method according to claim 5, characterized in that, The detection of whether the lidar has been blocked includes: The number of secondary echo signals received within the target detection period is obtained, wherein the secondary echo signal refers to the echo signal of the laser beam emitted by the laser emitting device reflected by the obstacle; Obtain the third ratio between the difference between the total number of laser beams and the number of secondary echo signals within the target detection period and the total number of laser beams within the target detection period; If the third ratio is greater than or equal to the second preset percentage, the occlusion event is determined to have occurred.

7. A dirt detection device, characterized in that, The device is applied to a vehicle equipped with at least one lidar, the lidar including a laser emitting device and a light-transmitting cover disposed on the emitting side of the laser emitting device, the device comprising: The signal acquisition module is used to acquire the first echo signal of the lidar within the target detection period when the lidar is detected to have a range reduction event. The first echo signal refers to the echo signal reflected by the light-transmitting cover plate after the laser beam emitted by the laser emitting device is reflected. The range reduction event refers to the event where the ratio between the actual range and the calibrated range of the lidar is less than a third preset percentage. The period detection module is used to determine whether the target detection period is an abnormal detection period based on the signal strength of the first echo signal. The event detection module is used to determine that a dirt event has occurred when the number of consecutive abnormal detection cycles is greater than or equal to a preset number. The dirt event refers to the event that dirt appears on the surface of the lidar's light-transmitting cover away from the laser emitting device. A range monitoring module is used to determine the distance between the obstacle and the vehicle as the actual range of the lidar if the detection rate of the lidar detecting an obstacle is less than a preset detection rate threshold, and to determine the occurrence of the range drop event when the ratio between the actual range of the lidar and the calibrated range is less than a third preset percentage.

8. A means of transportation, characterized in that, The vehicle includes a processor, a memory, and at least one lidar, the memory storing computer program instructions that are invoked by the processor to execute the dirt detection method as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program code, which is invoked by a processor to execute the dirt detection method as described in any one of claims 1-6.

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