Denoising method and device of laser radar, terminal equipment and storage medium

Abstract

The invention is suitable for the technical field of radars, and provides a de-noising method and device of a laser radar, terminal equipment and a storage medium, and the method comprises the steps: employing a first threshold voltage to detect a first echo reflected by a detection region corresponding to the laser radar when sunlight noise exists in a current detection environment; when the sunlight noise does not exist in the current detection environment, a second threshold voltage is adopted to detect the first echo, and the second threshold voltage is smaller than the first threshold voltage. Therefore, the high threshold voltage is adopted to detect the echo when the sunlight noise exists so as to filter the sunlight noise, and the low threshold voltage is adopted to detect the echo when the sunlight noise does not exist so as to ensure the echo detection accuracy when the sunlight noise does not exist, so that the sunlight noise is removed, and the reliability of the point cloud data is improved; and the sunlight noise is directly removed in the echo signal extraction stage, and subsequent processing on the point cloud data is not needed, so that the calculation complexity is low, and the calculation resources of a chip are saved.

Description

Technical Field

[0001] The present application belongs to the field of radar technology, and in particular, relates to a laser radar denoising method, apparatus, terminal equipment and computer-readable storage medium. Background Art

[0002] With the rise of laser radar and millimeter wave radar, various radar devices have been widely used in robots, vehicles and other equipment to perform distance measurement, target detection, etc. For example, laser radar can measure the propagation distance between the laser emitter and the target object, analyze the reflected energy size, amplitude, frequency and phase of the reflected spectrum on the surface of the target object, and thus present accurate three-dimensional structural information of the target object.

[0003] In laser radar, silicon photomultiplier (SiPM) is usually used as the receiving sensor of laser radar. It has the characteristics of high receiving sensitivity, but is easily affected by ambient light (mainly sunlight), resulting in a low signal-to-noise ratio of the echo data obtained by the laser radar, which in turn affects the detection accuracy of the laser radar.

[0004] In related technologies, sunlight noise in point cloud data is usually removed through algorithm models, but some points of actual objects will also be removed, which not only affects the reliability of the point cloud data, but also has high computational complexity and consumes computing resources. Summary of the invention

[0005] The embodiments of the present application provide a laser radar denoising method, apparatus, terminal device and computer-readable storage medium, which can solve the problem that removing sunlight noise in point cloud data through an algorithm model will remove some points of actual objects, thereby not only affecting the reliability of the point cloud data, but also increasing the computational complexity and consuming computing resources.

[0006] In a first aspect, an embodiment of the present application provides a laser radar denoising method, comprising: when there is sunlight noise in the current detection environment, using a first threshold voltage to detect a first echo reflected by a detection area corresponding to the laser radar; when there is no sunlight noise in the current detection environment, using a second threshold voltage to detect the first echo, wherein the second threshold voltage is less than the first threshold voltage.

[0007] In a possible implementation manner of the first aspect, when sunlight noise exists in the current detection environment, before using the first threshold voltage to detect the first echo reflected from the detection area corresponding to the laser radar, the method further includes:

[0008] Lowering the driving voltage of the SiPM in the laser radar from a first voltage value to a second voltage value, and raising the driving voltage of the SiPM to the first voltage value after a first preset time;

[0009] Using a second threshold voltage to detect a second echo reflected from the detection area;

[0010] If the second echo is detected, it is determined that sunlight noise exists in the current detection environment;

[0011] If the second echo is not detected, it is determined that there is no sunlight noise in the current detection environment.

[0012] Optionally, in another possible implementation manner of the first aspect, the first preset duration is determined according to a difference between the first voltage value and the second voltage value and a hardware parameter of the SiPM.

[0013] Optionally, in another possible implementation of the first aspect, before the first threshold voltage is used to detect the first echo reflected from the detection area corresponding to the laser radar, the method further includes:

[0014] The driving voltage of the SiPM is maintained at a first voltage value.

[0015] Optionally, in yet another possible implementation manner of the first aspect, before the second threshold voltage is used to detect the first echo, the method further includes:

[0016] Controlling the laser transmitter in the laser radar to emit a laser beam into the detection area;

[0017] The driving voltage of the SiPM is reduced from the first voltage value to the second voltage value, and then increased to the first voltage value after a second preset time period.

[0018] Optionally, in another possible implementation of the first aspect, the second preset duration is determined based on the difference between the first voltage value and the second voltage value, the hardware parameters of the SiPM, and the propagation time of the laser beam inside the lidar.

[0019] Optionally, in another possible implementation manner of the first aspect, before the first threshold voltage is used to detect the first echo reflected from the detection area corresponding to the laser radar, the method further includes:

[0020] Control the laser transmitter in the laser radar to emit a laser beam into the detection area.

[0021] In the second aspect, an embodiment of the present application provides a denoising device for a laser radar, comprising: a first detection module, for detecting a first echo reflected by a detection area corresponding to the laser radar using a first threshold voltage when sunlight noise exists in a current detection environment; a second detection module, for detecting the first echo using a second threshold voltage when no sunlight noise exists in the current detection environment, wherein the second threshold voltage is less than the first threshold voltage.

[0022] In a possible implementation manner of the second aspect, the apparatus further includes:

[0023] A first voltage adjustment module, used to reduce the driving voltage of the SiPM in the laser radar from a first voltage value to a second voltage value, and increase the driving voltage of the SiPM to the first voltage value after a first preset time;

[0024] A third detection module, used for detecting a second echo reflected from the detection area by using a second threshold voltage;

[0025] A first determination module is used to determine that sunlight noise exists in the current detection environment if the second echo is detected;

[0026] The second determination module is used to determine that there is no sunlight noise in the current detection environment if the second echo is not detected.

[0027] Optionally, in another possible implementation manner of the second aspect, the first preset duration is determined according to a difference between the first voltage value and the second voltage value and a hardware parameter of the SiPM.

[0028] Optionally, in another possible implementation of the second aspect, the apparatus further includes:

[0029] The first maintaining module is used to maintain the driving voltage of the SiPM at a first voltage value.

[0030] Optionally, in yet another possible implementation of the second aspect, the apparatus further includes:

[0031] A first transmitting module is used to control a laser transmitter in the laser radar to transmit a laser beam into a detection area;

[0032] The second voltage adjustment module is used to reduce the driving voltage of the SiPM from the first voltage value to the second voltage value, and increase it to the first voltage value after a second preset time period.

[0033] Optionally, in another possible implementation of the second aspect, the second preset duration is determined based on the difference between the first voltage value and the second voltage value, the hardware parameters of the SiPM, and the propagation time of the laser beam inside the lidar.

[0034] Optionally, in another possible implementation of the second aspect, the apparatus further includes:

[0035] The second transmitting module is used to control the laser transmitter in the laser radar to emit a laser beam into the detection area.

[0036] In a third aspect, an embodiment of the present application provides a terminal device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the laser radar denoising method as described above when executing the computer program.

[0037] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the laser radar denoising method as described above.

[0038] In a fifth aspect, an embodiment of the present application provides a computer program product, which, when executed on a terminal device, enables the terminal device to execute the laser radar denoising method as described above.

[0039] Compared with the prior art, the embodiments of the present application have the following beneficial effects: when sunlight noise exists, a high threshold voltage is used to detect the echo to filter out the sunlight noise; when sunlight noise does not exist, a low threshold voltage is used to detect the echo to filter out the sunlight noise while ensuring the accuracy of echo detection when there is no sunlight noise. This not only removes the sunlight noise and improves the reliability of the point cloud data, but also directly removes the sunlight noise in the echo signal extraction stage without the need for subsequent processing of the point cloud data, thereby reducing the computational complexity and saving the computing resources of the chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 It is a flowchart of a laser radar denoising method provided in one embodiment of the present application;

[0042] Figure 2 is a schematic diagram of an echo waveform provided by an embodiment of the present application;

[0043] Figure 3 It is a waveform diagram of a plurality of groups of echoes with sunlight noise superimposed after the driving voltage of the SiPM is increased from the second voltage value to the first voltage value, provided by one embodiment of the present application;

[0044] Figure 4 It is a schematic diagram of the structure of a laser radar denoising device provided in an embodiment of the present application;

[0045] Figure 5 It is a schematic diagram of the structure of the terminal device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0047] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0048] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0049] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0050] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0051] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0052] The following is a detailed description of the laser radar denoising method, apparatus, terminal device, storage medium and computer program provided in the present application with reference to the accompanying drawings.

[0053] Figure 1 A schematic flow chart of a laser radar denoising method provided in an embodiment of the present application is shown.

[0054] like Figure 1 As shown, the denoising method of the laser radar includes the following steps:

[0055] Step 101, when sunlight noise exists in the current detection environment, a first threshold voltage is used to detect a first echo reflected from a detection area corresponding to the laser radar.

[0056] It should be noted that the denoising method of the laser radar of the embodiment of the present application can be performed by the denoising device of the laser radar of the embodiment of the present application. The denoising device of the laser radar of the embodiment of the present application can be configured in any terminal device to execute the denoising method of the laser radar of the embodiment of the present application. For example, the denoising device of the laser radar of the embodiment of the present application can be configured in the processing unit of the laser radar to control the signal transmission and signal reception process of the laser radar and improve the quality of the echo data.

[0057] The current detection environment may refer to the working environment that the laser radar is currently in. For example, the current detection environment corresponding to the laser radar may be indoors, outdoors, a strong light environment or a weak light environment, etc., which is not limited in the embodiments of the present application.

[0058] The first threshold voltage may refer to a higher threshold voltage used for detecting an echo waveform in a detection environment with sunlight noise.

[0059] For example, if Figure 2As shown, it is a schematic diagram of an echo waveform provided by an embodiment of the present application, wherein start is the leading edge value of the echo waveform, stop is the trailing edge value of the echo waveform, and the dotted line is used to represent the threshold voltage for detecting the echo; it can be seen that if there is a pulse with a voltage value greater than the threshold voltage in the signal received by the laser radar, then the pulse can be determined as an echo, and the waveform between the detected leading edge value and the corresponding trailing edge value can be determined as an echo.

[0060] Among them, the detection area corresponding to the laser radar may refer to the area range that the laser radar can currently detect.

[0061] Among them, the first echo may refer to an echo extracted from a received signal (a signal reflected from an object in the detection area) after the laser radar emits a laser beam.

[0062] In the embodiment of the present application, if it is determined that there is sunlight noise in the current detection environment, such as being under sunlight or other strong light sources, then when the laser radar receives the echo signal, the echo signal will contain not only the reflected light corresponding to the laser beam reflected by the object in the detection area (i.e., the first echo), but also sunlight noise. And because the voltage value of sunlight noise is usually small, and the voltage value of a normal echo waveform under sunlight is usually high, a higher first threshold voltage can be used to detect the first echo. That is, Figure 2 The threshold voltage shown in is determined as the first threshold voltage, so that all the echo signals such as Figure 2 The echo waveforms shown can all be detected as echo waveforms for subsequent generation of point cloud data; and all echo signals that do not meet Figure 2 The waveforms related to the first threshold voltage will be filtered out, thereby filtering out the sunlight noise.

[0063] It should be noted that, in actual use, the specific value of the first threshold voltage can be determined according to actual needs and specific application scenarios, or the specific value of the first threshold voltage can be determined through experiments, and the embodiments of the present application do not limit this.

[0064] As a possible implementation method, a light sensor may be arranged inside or near the laser radar to detect the light intensity of the current detection environment corresponding to the laser radar, and then determine whether there is sunlight noise in the current detection environment according to the light intensity of the current detection environment. As an example, when the light intensity of the current detection environment is greater than or equal to the light intensity threshold, it is determined that there is sunlight noise in the current detection environment; when the light intensity of the current detection environment is less than the light intensity threshold, it is determined that there is no sunlight noise in the current detection environment.

[0065] Furthermore, in order to improve the accuracy of determining whether sunlight noise exists in the current detection environment, the SiPM in the laser radar can be used to detect whether sunlight noise exists at present, so as to further improve the reliability of sunlight noise removal. That is, in a possible implementation of the present application, before the above step 101, it can also include:

[0066] Lowering the driving voltage of the SiPM in the laser radar from a first voltage value to a second voltage value, and raising the driving voltage of the SiPM to the first voltage value after a first preset time;

[0067] Using a second threshold voltage to detect a second echo reflected from the detection area;

[0068] If the second echo is detected, it is determined that sunlight noise exists in the current detection environment;

[0069] If the second echo is not detected, it is determined that there is no sunlight noise in the current detection environment.

[0070] The first voltage value may refer to a driving voltage value that can enable the SiPM to have good detection sensitivity to optical signals.

[0071] The second voltage value may refer to a driving voltage value that makes the SiPM unable to detect the optical signal normally.

[0072] It should be noted that the first voltage value is greater than the second voltage value. In actual use, the specific values ​​of the first voltage value and the second voltage value can be determined according to the actual performance of the SiPM used in the laser radar, and the embodiment of the present application does not limit this.

[0073] The second threshold voltage may refer to a lower threshold voltage used for detecting an echo waveform; and the second threshold voltage is smaller than the first threshold voltage.

[0074] It should be noted that even if there is sunlight noise in the current detection environment, the voltage value of the pulse corresponding to the sunlight noise reflected in the echo is relatively small. Therefore, the second threshold voltage can be set to a smaller value to reliably detect the sunlight noise in the current detection environment and prevent the second threshold voltage from being set too large, which may lead to missed detection of the echo waveform corresponding to the sunlight noise, and further lead to incorrect judgment of the type of the current detection environment.

[0075] The second echo may refer to an echo detected from a signal received by the laser radar before each emission of a laser beam, that is, an echo corresponding to sunlight noise.

[0076] As a possible implementation method, the lower the driving voltage of the SiPM, the lower the detection sensitivity to the light signal, and the higher the driving voltage of the SiPM, the higher the detection sensitivity to the light signal. After the driving voltage of the SiPM is lowered and then raised again, the driving voltage of the SiPM will oscillate, resulting in the driving voltage value of the SiPM being slightly higher than the first voltage value in a short time after the driving voltage of the SiPM is increased to the first voltage value. As a result, the driving voltage of the SiPM has a higher detection sensitivity to the light signal in a short time after the driving voltage of the SiPM is increased to the first voltage value. In this way, sunlight noise with a lower voltage value can be reliably detected.

[0077] Therefore, in the embodiment of the present application, before each laser beam is emitted, the driving voltage of the SiPM can be reduced from the first voltage value to the second voltage value, and after a preset time, the driving voltage of the SiPM can be increased to the first voltage value, and then the SiPM is driven to perform echo detection using a lower second threshold. If the second echo reflected in the detection area is detected, it can be determined that there is sunlight noise in the current detection environment; if the second echo is not detected, it can be determined that there is no sunlight noise in the current detection environment.

[0078] It should be noted that if Figure 3 As shown, it is a waveform schematic diagram of the superposition of multiple groups of echoes with sunlight noise after the driving voltage of SiPM is increased from the second voltage value to the first voltage value provided in an embodiment of the present application. It can be seen that after the driving voltage of SiPM is first reduced to the second voltage value and then increased to the first voltage value, the echo waveform 301 corresponding to the obvious sunlight noise can be detected, thereby proving the effectiveness of the method of the embodiment of the present application in detecting sunlight noise.

[0079] As a possible implementation manner, the first preset duration may be determined according to the difference between the first voltage value and the second voltage value and the hardware parameters of the SiPM.

[0080] It is understandable that in actual applications, after the driving voltage of the SiPM is reduced or increased, the driving voltage value of the SiPM will not be directly reduced or increased to the target voltage value, but there is a certain delay, and this specific delay is related to the adjusted voltage amplitude and the hardware parameters of the SiPM. Therefore, before the driving voltage of the SiPM is increased to the first voltage value, it is necessary to ensure that the driving voltage of the SiPM has been reduced to the second voltage value; thus, the delay of the driving voltage from the first voltage value to the second voltage value can be determined based on the difference between the first voltage value and the second voltage value and the hardware parameters of the SiPM, and then the first preset time length can be determined as any time length greater than the delay.

[0081] It should be noted that, since the scanning of the laser radar has a high frequency, in order to ensure that the sunlight noise is detected without affecting each laser emission, the first preset time length can be set to a smaller value. For example, if the delay of the SiPM driving voltage decreasing from the first voltage value to the second voltage value is 40ns, the first preset time length can be determined to be 50ns, 100ns, 200ns, etc., and the embodiment of the present application does not limit this.

[0082] Furthermore, when sunlight noise exists in the current detection environment, in order to ensure the detection sensitivity of the SiPM, the driving voltage of the SiPM can be kept at a relatively high level. That is, in a possible implementation of the embodiment of the present application, before the above step 101, the following may be included:

[0083] The driving voltage of the SiPM is maintained at a first voltage value.

[0084] In the embodiment of the present application, since part of the laser beam emitted by the laser radar will be reflected inside the laser radar, stray light will be formed; and since the pulse width of the stray light is wide, it is easy to superimpose with the echo pulse reflected by the close-range object, so that the echo reflected by the close-range object cannot be normally identified, thereby affecting the point cloud quality and the detection accuracy of the laser radar. However, when it is determined that there is sunlight noise in the current detection environment, that is, when the second echo corresponding to the sunlight noise can be detected through the aforementioned steps, it can usually be explained that there is no object that can block the sunlight near the laser radar, that is, there is no actual object in the close distance, so in the case of sunlight noise in the current detection environment, stray light will not affect normal object detection, that is, it will not affect the point cloud quality. Therefore, in the case of sunlight noise in the current detection environment, the influence of stray light on echo detection can be ignored, and the driving voltage of SiPM can be directly maintained at a higher first voltage value to ensure the detection sensitivity of SiPM, thereby not only removing the influence of sunlight noise and stray light on the point cloud quality, improving the point cloud quality, but also no longer adjusting the driving voltage of SiPM, further reducing resource consumption.

[0085] Furthermore, since the laser radar emits laser beams periodically, and the laser radar is usually moving during operation, or the detected object is moving, the detection environment of the laser radar usually changes in real time. Therefore, in order to ensure the reliability of sunlight noise removal, it is possible to determine whether there is sunlight noise in the current detection environment before each laser beam is emitted, and then emit the laser beam after the determination is completed and the echo detection strategy is determined. That is, in a possible implementation of the embodiment of the present application, before the above step 101, it can also include:

[0086] Control the laser transmitter in the laser radar to emit a laser beam into the detection area.

[0087] The laser emitter may be any type of device that can generate laser, and the present application embodiment does not limit this. For example, the laser emitter may be a laser diode (LD).

[0088] As a possible implementation method, before each laser beam is emitted, it is determined whether there is sunlight noise in the current detection environment. After the determination is completed and the echo detection strategy is determined, the laser transmitter in the laser radar is controlled to emit the laser beam, and then the SiPM is driven to detect the first echo with a first threshold voltage.

[0089] Step 102: When there is no sunlight noise in the current detection environment, a second threshold voltage is used to detect the first echo, wherein the second threshold voltage is smaller than the first threshold voltage.

[0090] In the embodiment of the present application, if it is determined that there is no sunlight noise in the current detection environment according to any of the aforementioned steps, the first echo can be detected with a lower second threshold voltage. Since there is no sunlight noise in the echo signal at this time, there is no need to consider filtering out the sunlight noise, so the first echo can be detected with a lower threshold voltage to ensure the detection accuracy of the first echo reflected by the actual object in the detection area as much as possible, so as to prevent the first echo emitted by the actual object from being missed.

[0091] Furthermore, since there is no sunlight noise in the current detection environment, that is, when the second echo corresponding to the sunlight noise is not detected through the aforementioned steps, it can usually be said that there may be an object blocking the sunlight near the laser radar, that is, there may be an actual object in close range. Therefore, when there is no sunlight noise in the current detection environment, stray light may affect normal object detection, thereby reducing the point cloud quality. Therefore, when there is no sunlight noise in the current detection environment, the influence of stray light on echo detection can also be removed to further improve the point cloud quality. That is, in a possible implementation method of the embodiment of the present application, before the above step 102, it can also include:

[0092] Controlling the laser transmitter in the laser radar to emit a laser beam into the detection area;

[0093] The driving voltage of the SiPM is reduced from the first voltage value to the second voltage value, and then increased to the first voltage value after a second preset time period.

[0094] As a possible implementation method, before each laser beam is emitted, it is possible to determine whether there is sunlight noise in the current detection environment. After the determination is completed and the echo detection strategy is determined, the laser transmitter in the laser radar is controlled to emit the laser beam, and then the SiPM is driven to detect the first echo. However, since the pulse width of the echo pulse of stray light is wide, it is easy to overlap with the echo pulse of close objects, thereby affecting the detection accuracy of close objects. Therefore, after driving the laser transmitter to emit the laser beam, the driving voltage of the SiPM can be adjusted immediately so that the SiPM cannot receive the echo corresponding to the stray light.

[0095] It is understandable that, since stray light is light reflected from inside the laser radar, the time when SiPM receives the echo corresponding to the stray light will be earlier than the time when it receives the echo reflected from the actual object in the detection area. Therefore, after the laser beam is emitted, the SiPM can be temporarily unable to receive the echo, and after a period of time, the SiPM can receive the echo normally, so that the SiPM cannot receive the echo corresponding to the stray light, so as to remove the stray light in the signal receiving stage. Therefore, after the laser emitter emits the laser beam, the driving voltage of the SiPM can be immediately reduced from the first voltage value to the second voltage value to reduce the detection sensitivity of the SiPM, so that the SiPM cannot receive the echo corresponding to the stray light; and after the second preset time, the driving voltage of the SiPM is increased from the second voltage value to the first voltage value, so that the SiPM recovers to the normal detection sensitivity after the second preset time, so as to normally receive the first echo reflected from the actual object in the detection area.

[0096] As a possible implementation manner, the second preset duration can be determined based on the difference between the first voltage value and the second voltage value, the hardware parameters of the SiPM, and the propagation time of the laser beam inside the laser radar.

[0097] The propagation time of the laser beam inside the laser radar may refer to the time from the emission moment of the laser beam to the moment when the SiPM receives the echo generated by the reflection of the laser beam inside the laser radar.

[0098] It is understandable that in actual applications, after the driving voltage of SiPM is reduced or increased, the driving voltage value of SiPM will not be directly reduced or increased to the target voltage value, but there will be a certain delay, and this specific delay is related to the adjusted voltage amplitude and the hardware parameters of SiPM. Therefore, before the driving voltage of SiPM is increased to the first voltage value, it is necessary to ensure that the driving voltage of SiPM has been reduced to the second voltage value; and, since the reason for reducing the driving voltage value of SiPM to the second voltage value is to prevent SiPM from receiving the echo corresponding to the stray light, the second preset time length should be greater than or equal to the propagation time of the laser beam inside the laser radar, so as to ensure that the driving voltage value of SiPM is always maintained at the second voltage value before the stray light propagates to SiPM.

[0099] Therefore, the time delay for the driving voltage to decrease from the first voltage value to the second voltage value can be determined based on the difference between the first voltage value and the second voltage value and the hardware parameters of the SiPM, and the larger value between the time delay and the propagation time of the laser beam inside the lidar can be determined. Then, the second preset time length can be determined to be a time length greater than or equal to and close to the larger value, so as to filter out stray light while preventing the omission of the echo reflected by the actual object, so as to further improve the accuracy of echo detection and the quality of the point cloud.

[0100] For example, assuming that the delay for reducing the driving voltage of the SiPM from the first voltage value to the second voltage value is 40ns, and the propagation time of the laser beam inside the laser radar is 60ns, the second preset time length can be determined as 60ns, 61ns, 65ns, 100ns, and so on; if the propagation time of the laser beam inside the laser radar is 30ns, the second preset time length can be determined as 40ns, 41ns, 50ns, 60ns, and so on.

[0101] It should be noted that the above examples are only exemplary and cannot be regarded as limiting the present application. In actual use, the specific value of the second preset time length can be determined according to actual needs and specific application scenarios, and the present application embodiment does not limit this.

[0102] The laser radar denoising method provided in the embodiment of the present application uses a first threshold voltage to detect the first echo reflected by the detection area corresponding to the laser radar when sunlight noise exists in the current detection environment, and uses a second threshold voltage less than the first threshold voltage to detect the first echo when sunlight noise does not exist in the current detection environment. Thus, by using a high threshold voltage to detect the echo when sunlight noise exists to filter out the sunlight noise, and using a low threshold voltage to detect the echo when sunlight noise does not exist, the sunlight noise is filtered out while ensuring the accuracy of echo detection when there is no sunlight noise, thereby not only removing the sunlight noise and improving the reliability of the point cloud data, but also directly removing the sunlight noise in the echo signal extraction stage, without the need for subsequent processing of the point cloud data, the computational complexity is low, and the computing resources of the chip are saved.

[0103] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0104] Corresponding to the laser radar denoising method described in the above embodiment, Figure 4 A schematic diagram of the structure of a laser radar denoising device provided in an embodiment of the present application is shown. For ease of explanation, only the parts related to the embodiment of the present application are shown.

[0105] Reference Figure 4 , the device 40 comprises:

[0106] The first detection module 41 is used to detect the first echo reflected by the detection area corresponding to the laser radar using a first threshold voltage when sunlight noise exists in the current detection environment;

[0107] The second detection module 42 is used to detect the first echo using a second threshold voltage when there is no sunlight noise in the current detection environment, wherein the second threshold voltage is smaller than the first threshold voltage.

[0108] In actual use, the laser radar denoising device provided in the embodiment of the present application can be configured in any terminal device to execute the aforementioned laser radar denoising method.

[0109] The laser radar denoising device provided in the embodiment of the present application uses a first threshold voltage to detect the first echo reflected by the detection area corresponding to the laser radar when sunlight noise exists in the current detection environment, and uses a second threshold voltage less than the first threshold voltage to detect the first echo when sunlight noise does not exist in the current detection environment. Thus, by using a high threshold voltage to detect the echo when sunlight noise exists to filter out the sunlight noise, and using a low threshold voltage to detect the echo when sunlight noise does not exist, the sunlight noise is filtered out while ensuring the accuracy of echo detection when there is no sunlight noise, thereby not only removing the sunlight noise and improving the reliability of the point cloud data, but also directly removing the sunlight noise in the echo signal extraction stage, without the need for subsequent processing of the point cloud data, the computational complexity is low, and the computing resources of the chip are saved.

[0110] In a possible implementation form of the present application, the above-mentioned device 40 further includes:

[0111] A first voltage adjustment module, used to reduce the driving voltage of the SiPM in the laser radar from a first voltage value to a second voltage value, and increase the driving voltage of the SiPM to the first voltage value after a first preset time;

[0112] A third detection module, used for detecting a second echo reflected from the detection area by using a second threshold voltage;

[0113] A first determination module is used to determine that sunlight noise exists in the current detection environment if the second echo is detected;

[0114] The second determination module is used to determine that there is no sunlight noise in the current detection environment if the second echo is not detected.

[0115] Optionally, in another possible implementation manner of the second aspect, the first preset duration is determined according to a difference between the first voltage value and the second voltage value and a hardware parameter of the SiPM.

[0116] Optionally, in another possible implementation of the second aspect, the apparatus 40 further includes:

[0117] The first maintaining module is used to maintain the driving voltage of the SiPM at a first voltage value.

[0118] Optionally, in yet another possible implementation of the second aspect, the apparatus 40 further includes:

[0119] A first transmitting module is used to control a laser transmitter in the laser radar to transmit a laser beam into a detection area;

[0120] The second voltage adjustment module is used to reduce the driving voltage of the SiPM from the first voltage value to the second voltage value, and increase it to the first voltage value after a second preset time period.

[0121] Optionally, in another possible implementation of the second aspect, the second preset duration is determined based on the difference between the first voltage value and the second voltage value, the hardware parameters of the SiPM, and the propagation time of the laser beam inside the lidar.

[0122] Optionally, in another possible implementation of the second aspect, the apparatus 40 further includes:

[0123] The second transmitting module is used to control the laser transmitter in the laser radar to emit a laser beam into the detection area.

[0124] It should be noted that the information interaction, execution process, etc. between the above-mentioned devices / units are based on the same concept as the method embodiment of the present application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0125] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0126] In order to implement the above embodiments, the present application also proposes a terminal device.

[0127] Figure 5 A schematic diagram of the structure of a terminal device according to an embodiment of the present application.

[0128] like Figure 5 As shown, the terminal device 200 includes:

[0129] A memory 210 and at least one processor 220, a bus 230 connecting different components (including the memory 210 and the processor 220), the memory 210 stores a computer program, and when the processor 220 executes the program, the laser radar denoising method described in the embodiment of the present application is implemented.

[0130] Bus 230 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor or a local bus using any of a variety of bus architectures. For example, these architectures include but are not limited to Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MAC) bus, Enhanced ISA bus, Video Electronics Standards Association (VESA) local bus and Peripheral Component Interconnect (PCI) bus.

[0131] The terminal device 200 typically includes a variety of electronic device readable media, which can be any available media that can be accessed by the terminal device 200, including volatile and non-volatile media, removable and non-removable media.

[0132] The memory 210 may also include computer system readable media in the form of volatile memory, such as random access memory (RAM) 240 and / or cache memory 250. The terminal device 200 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 260 may be used to read and write non-removable, non-volatile magnetic media ( Figure 5 not shown, usually called a "hard drive"). Although Figure 5 Not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk"), and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical medium) may be provided. In these cases, each drive may be connected to bus 230 via one or more data medium interfaces. Memory 210 may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of the various embodiments of the present application.

[0133] A program / utility 280 having a set (at least one) of program modules 270 may be stored, for example, in the memory 210, such program modules 270 including, but not limited to, an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment. The program modules 270 generally perform the functions and / or methods of the embodiments described herein.

[0134] The terminal device 200 can also communicate with one or more external devices 290 (e.g., keyboard, pointing device, display 291, etc.), and can also communicate with one or more devices that enable users to interact with the terminal device 200, and / or communicate with any device that enables the terminal device 200 to communicate with one or more other computing devices (e.g., network card, modem, etc.). This communication can be carried out through an input / output (I / O) interface 292. In addition, the terminal device 200 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN) and / or public network, such as the Internet) through a network adapter 293. As shown in the figure, the network adapter 293 communicates with other modules of the terminal device 200 through a bus 230. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the terminal device 200, including but not limited to: microcode, device driver, redundant processing unit, external disk drive array, RAID system, tape drive, and data backup storage system, etc.

[0135] The processor 220 executes various functional applications and data processing by running the programs stored in the memory 210 .

[0136] It should be noted that the implementation process and technical principles of the terminal device of this embodiment refer to the aforementioned explanation of the denoising method of the laser radar in the embodiment of the present application, and will not be repeated here.

[0137] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

[0138] An embodiment of the present application provides a computer program product. When the computer program product is run on a terminal device, the terminal device can implement the steps in the above-mentioned method embodiments when executing the computer program product.

[0139] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the camera / terminal device, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk or an optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.

[0140] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0141] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0142] In the embodiments provided in the present application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0143] 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 distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0144] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A laser radar denoising method, characterized in that: include: When sunlight noise exists in the current detection environment, a first threshold voltage is used to detect a first echo reflected from a detection area corresponding to the laser radar; When there is no sunlight noise in the current detection environment, a second threshold voltage is used to detect the first echo, wherein the second threshold voltage is smaller than the first threshold voltage.

2. The method according to claim 1, characterized in that Before the first echo reflected by the detection area corresponding to the laser radar is detected by using the first threshold voltage when sunlight noise exists in the current detection environment, the method further includes: The driving voltage of the silicon photomultiplier tube SiPM in the laser radar is reduced from a first voltage value to a second voltage value, and the driving voltage of the SiPM is increased to the first voltage value after a first preset time period; using the second threshold voltage to detect a second echo reflected from the detection area; If the second echo is detected, it is determined that sunlight noise exists in the current detection environment; If the second echo is not detected, it is determined that there is no sunlight noise in the current detection environment.

3. The method according to claim 2, characterized in that The first preset duration is determined according to a difference between the first voltage value and the second voltage value and a hardware parameter of the SiPM.

4. The method according to claim 2, characterized in that Before using the first threshold voltage to detect the first echo reflected by the detection area corresponding to the laser radar, the method further includes: The driving voltage of the SiPM is maintained at the first voltage value.

5. The method according to claim 2, characterized in that Before the second threshold voltage is used to detect the first echo, the method further includes: Controlling the laser transmitter in the laser radar to emit a laser beam into the detection area; The driving voltage of the SiPM is reduced from the first voltage value to the second voltage value, and then increased to the first voltage value after a second preset time period.

6. The method according to claim 5, characterized in that The second preset duration is determined based on the difference between the first voltage value and the second voltage value, the hardware parameters of the SiPM, and the propagation time of the laser beam inside the laser radar.

7. The method according to any one of claims 1 to 6, characterized in that: Before using the first threshold voltage to detect the first echo reflected by the detection area corresponding to the laser radar, the method further includes: The laser transmitter in the laser radar is controlled to emit a laser beam into the detection area.

8. A laser radar denoising device, characterized in that: include: A first detection module, used for detecting a first echo reflected from a detection area corresponding to the laser radar using a first threshold voltage when sunlight noise exists in a current detection environment; The second detection module is used to detect the first echo using a second threshold voltage when there is no sunlight noise in the current detection environment, wherein the second threshold voltage is smaller than the first threshold voltage.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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