Laser radar scanning method and scanning device

Abstract

A laser radar scanning method and scanning device thereof relate to the field of laser radar technology. The laser radar scanning method includes: controlling the laser radar to scan in a first mode and acquiring point cloud data; determining key areas and non-key areas based on the point cloud data; controlling the laser radar to continue scanning in the first mode and determining whether the area currently scanned by the laser radar is in a key area; if so, switching the laser radar's operating mode from the first mode to a second mode, the second mode corresponding to a resolution greater than the resolution corresponding to the first mode; if not, returning to the step of controlling the laser radar to scan in the first mode and acquiring point cloud data. The laser radar scanning method can scan a wider field of view while simultaneously performing high-resolution tracking scanning of key targets within a small range, thereby achieving a balance between satisfying a wide field of view and effective high resolution.

Description

Technical Field

[0001] The present invention relates to the field of laser radar technology, and in particular to a laser radar scanning method and a scanning device thereof. Background Art

[0002] When LiDAR is applied in the field of autonomous driving, it can be used to detect pedestrians, vehicles, and other obstacles. However, LiDAR generally has a contradiction between its field of view width and angular resolution. That is, when hardware resources are limited, increasing the field of view angle will inevitably reduce the angular resolution, and increasing the angular resolution will inevitably cause the scanning field of view to shrink. You cannot have both.

[0003] In the existing technology, two types of measures are generally used to ensure high resolution within a wide field of view: one is to increase the density of radar scan lines and the laser emission frequency in order to emit more light pulses per unit time and generate more pixels per square degree of field of view; the other is to enhance the resolution of the receiving end and use a sensor array to decompose an echo spot into multiple pixels. However, both of these existing methods have high requirements for hardware resources. The first method will lead to problems such as increased laser power consumption and increased heat generation of the entire device; the second method will consume a large amount of hardware resources due to sampling of multiple units. Therefore, how to solve the above problems has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0004] The object of the present invention is to provide a laser radar scanning method and a scanning device thereof, which can scan a wider field of view while performing high-resolution tracking scanning of key targets in a small range, thereby achieving a balance between satisfying a large field of view width and effective high resolution.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows:

[0006] In a first aspect, an embodiment of the present invention provides a laser radar scanning method, which includes: controlling the laser radar to scan in a first mode and obtain point cloud data; determining key areas and non-key areas based on the point cloud data; controlling the laser radar to continue scanning in the first mode, and determining whether the area currently scanned by the laser radar is in a key area; if so, switching the operating mode of the laser radar from the first mode to the second mode, the resolution corresponding to the second mode being greater than the resolution corresponding to the first mode; if not, returning to the step of controlling the laser radar to scan in the first mode and obtain point cloud data. This laser radar scanning method can scan a wider field of view while performing high-resolution tracking scanning of key targets within a small range, thereby achieving a balance between satisfying a wide field of view and effective high resolution.

[0007] Optionally, a laser radar is installed on a target vehicle to scan the external environment of the target vehicle and determine key areas and non-key areas based on the point cloud data, including: determining the ground plane area where the target vehicle is located based on the point cloud data, and filtering out obstacles above the ground plane area based on the ground plane area; determining a target to be selected from the obstacles based on at least two consecutive frames of point cloud data, the target to be selected being an obstacle in which the number of point clouds in at least two consecutive frames of point cloud data is greater than a preset number; determining a key target based on the movement direction of the target to be selected and the movement direction of the target vehicle, and the area where the key target is located is the key area.

[0008] Optionally, the key target is determined based on the movement direction of the target to be selected and the movement direction of the target car, including: obtaining the movement direction of the target to be selected and the movement direction of the target car; analyzing whether the movement direction of the target to be selected and the movement direction of the target car intersect; if so, determining that the target to be selected is the key target; if not, determining that the target to be selected is a non-key target.

[0009] Optionally, obtaining the movement direction of the target to be selected and the movement direction of the target car includes: calculating the movement direction of the target to be selected based on at least two consecutive frames of point cloud data; and determining the movement direction of the target car based on the direction of the central axis of the field of view of the laser radar.

[0010] Optionally, the laser radar scanning method further includes: re-determining the key target after each frame of the laser radar scan is completed.

[0011] Optionally, the laser radar includes a receiving circuit, which includes: a sensor array having at least two sensor units; at least two amplifiers, respectively connected one-to-one with the at least two sensor units; at least two sampling circuits, respectively connected one-to-one with the at least two amplifiers; and switching between the first mode and the second mode is achieved by adding a switching circuit between the at least two amplifiers and the at least two sampling circuits.

[0012] Optionally, the switching circuit includes: a switching circuit, connected between the amplifier and the sampling circuit, used to allow the amplified signals of at least two amplifiers to be combined through the switching circuit and connected to any one of the sampling circuits, or to allow the amplified signals of at least two amplifiers to be connected one-to-one with at least two sampling circuits through the switching circuit; a controller, electrically connected to the switching circuit, used to control the switching circuit to turn on one of the sampling circuits or turn on each of the sampling circuits.

[0013] Optionally, the switching circuit includes: at least two first single-pole double-throw switches, the common end of each first single-pole double-throw switch is connected to each amplifier one-to-one, and the normally open end of each first single-pole double-throw switch is connected to each sampling circuit; a second single-pole double-throw switch, the normally open end of the second single-pole double-throw switch is connected to the normally open end of any first single-pole double-throw switch, the common end of the second single-pole double-throw switch is connected to any sampling circuit, and the normally closed end of the second single-pole double-throw switch is connected to the normally closed end of each first single-pole double-throw switch after being combined.

[0014] Optionally, when the laser radar includes at least two fields of view, each field of view corresponds to a receiving circuit and a switching circuit electrically connected to the receiving circuit, wherein the sampling circuit portion in the receiving circuits corresponding to at least two fields of view is shared.

[0015] Optionally, the number of sampling circuits corresponding to at least two fields of view is equal to the number of sensor units corresponding to each field of view.

[0016] In the second aspect, an embodiment of the present invention also provides a laser radar scanning device, including: a first scanning module, used to control the laser radar to scan in a first mode and obtain point cloud data; a first determination module, used to determine key areas and non-key areas based on the point cloud data; a judgment module, used to control the laser radar to continue scanning in the first mode, and judge whether the area currently scanned by the laser radar is in the key area; if so, switch the working mode of the laser radar from the first mode to the second mode, and the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode; if not, return to the step of controlling the laser radar to scan in the first mode and obtain point cloud data.

[0017] In a third aspect, an embodiment of the present invention further provides a computer device comprising a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the instruction processing device is running, the processor and the storage medium communicate via the bus, and the processor executes the machine-readable instructions to perform the above method.

[0018] The beneficial effects of the present invention include:

[0019] The laser radar scanning method provided by the present application includes: controlling the laser radar to scan in a first mode and obtain point cloud data; determining key areas and non-key areas based on the point cloud data; controlling the laser radar to continue scanning in the first mode, and judging whether the area currently scanned by the laser radar is in the key area; if so, switching the working mode of the laser radar from the first mode to the second mode, the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode; if not, returning to the step of controlling the laser radar to scan in the first mode and obtain point cloud data. The present application first uses a low-resolution mode (i.e., the resolution corresponding to the first mode) to scan to determine the key area and the non-key area; then, during normal driving, the laser radar is used to continue scanning at a low resolution and judge whether the currently scanned area enters the key area. When entering the key area, the high-resolution (i.e., the resolution corresponding to the second mode) is used for scanning. When not entering the key area (i.e., in the non-key area), the low-resolution scanning is resumed. In this way, a laser radar can scan a wider field of view while performing high-resolution scanning and tracking of obstacles in a small key area, and low-resolution tracking of obstacles in non-key areas. In this way, on the one hand, this application can ensure high-resolution tracking of obstacles that affect driving safety; on the other hand, compared with the existing technology, this application has low requirements for hardware resources, will not cause an increase in the power consumption of the lidar, and does not require complex calculations and processing, thereby achieving a balance between meeting the requirements of a large field of view width and effective high resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 One of the flowcharts of the laser radar scanning method provided in an embodiment of the present invention;

[0022] Figure 2 A second flow chart of the laser radar scanning method provided in an embodiment of the present invention;

[0023] Figure 3 The third flowchart of the laser radar scanning method provided by an embodiment of the present invention;

[0024] Figure 4 A point cloud image obtained by a laser radar scanning method in the prior art;

[0025] Figure 5 A point cloud image obtained by the laser radar scanning method provided in an embodiment of the present invention;

[0026] Figure 6 A schematic diagram of the optical path of a laser radar provided in an embodiment of the present invention;

[0027] Figure 7 A schematic structural diagram of a switching circuit provided in an embodiment of the present invention;

[0028] Figure 8 A schematic structural diagram of a shared sampling circuit provided in an embodiment of the present invention;

[0029] Figure 9 A schematic diagram of the structure of a computer device provided in an embodiment of the present invention.

[0030] Icons: 11-optical fiber; 12-collimating mirror; 13-reflector; 14-perforated reflector; 15-scanning unit; 16-receiving lens; 17-sensor array; 171-sensor unit; 18-receiving board; 21-controller; 22-amplifier; 23-first single-pole double-throw switch; 24-second single-pole double-throw switch; 25-sampling circuit; 510-processor; 520-storage medium; 530-bus. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0034] First embodiment

[0035] Please refer to Figure 1 This embodiment provides a laser radar scanning method, which includes the following steps:

[0036] S100: Control the laser radar to scan in a first mode and obtain point cloud data.

[0037] It should be noted that, in this embodiment, the above-mentioned first mode is a mode corresponding to low resolution, that is, step S100 is to first perform a lidar scan in a low-resolution mode and obtain point cloud data. It should be noted that the lidar provided in this application can be installed on a target car to scan the external environment of the target car to assist driving. Of course, in addition to this, the lidar can also be applied to other devices. Specifically, this application does not limit this, but for the sake of ease of explanation and understanding, in this embodiment, the lidar is mainly used on a target car as an example for illustration.

[0038] The point cloud data obtained by the laser radar scanning may include two consecutive frames, so that it is convenient to compare the point cloud data of different frames in the subsequent steps to determine the key areas and non-key areas.

[0039] S200: Determine key areas and non-key areas based on point cloud data.

[0040] Among them, in this embodiment, when the laser radar is applied to the target car, the above-mentioned key areas correspond to areas that have an impact on the driving safety of the target car, for example, the area where vehicles traveling around the target car are located, the area where pedestrians are located around the target car, and the area where objects are located around the target car. These can be collectively referred to as areas where obstacles are located during the driving of the target car. Specifically, non-key areas are other areas outside the key areas. The specific division of key areas and non-key areas can be determined by those skilled in the art according to actual needs, and this application does not impose specific restrictions.

[0041] For example, please refer to Figure 2 When the laser radar is installed on the target vehicle and is used to scan the external environment of the target vehicle, the above step S200, determining the key area and the non-key area based on the point cloud data, can be achieved by the following methods:

[0042] S210 : Determine the ground plane area where the target vehicle is located based on the point cloud data, and filter out obstacles located above the ground plane area based on the ground plane area.

[0043] That is, the ground plane and obstacles above the ground plane are obtained based on the point cloud data. Obstacles above the ground plane can be screened out through object echoes (that is, obtained based on the echo data scanned by the lidar radar).

[0044] S220 . Determine a target to be selected from obstacles based on at least two consecutive frames of point cloud data. The target to be selected is an obstacle whose number of point clouds in at least two consecutive frames of point cloud data is greater than a preset number.

[0045] The at least two frames of point cloud data are for the convenience of comparison. For example, three frames of point cloud data or more than three frames of point cloud data may also be selected.

[0046] In this embodiment, the target to be selected is an obstacle whose point cloud count in at least two consecutive frames of point cloud data is greater than a preset number. For example, when the preset number is 3, the target to be selected is an obstacle whose point cloud count in two consecutive frames of point cloud data is greater than 3. Of course, the preset number of 3 is only an example given in this application. In other embodiments, the preset number can also be 4, 5, 7, etc., and this application does not impose any specific limitations.

[0047] S230: Determine a key target according to the moving direction of the candidate target and the moving direction of the target vehicle, and the area where the key target is located is the key area.

[0048] For example, in this embodiment, please refer to Figure 3 The above step S230, determining the key target according to the movement direction of the target to be selected and the movement direction of the target car, can be achieved by the following methods:

[0049] S231: Obtain the moving direction of the target to be selected and the moving direction of the target car.

[0050] The above step S231, obtaining the movement direction of the target to be selected and the movement direction of the target vehicle, can be implemented in the following manner:

[0051] The moving direction of the target to be selected is calculated based on at least two consecutive frames of point cloud data; and the moving direction of the target car is determined based on the direction of the central axis of the field of view of the laser radar.

[0052] It should be noted that the direction of the central axis of the laser radar's field of view is the direction of movement of the target vehicle.

[0053] S232: Analyze whether the moving direction of the target to be selected intersects with the moving direction of the target vehicle.

[0054] If so, the target to be selected is determined to be a key target;

[0055] If not, the target to be selected is determined to be a non-key target.

[0056] When the moving direction of the target to be selected intersects with the moving direction of the target car, the target to be selected may affect the driving safety of the target car, so it is determined to be a key target; similarly, when the moving direction of the target to be selected does not intersect with the moving direction of the target car (that is, they are on parallel trajectories), it is highly likely that the target to be selected will not affect the driving safety of the target car, so it can be determined as a non-key target.

[0057] S300: Control the laser radar to continue scanning in the first mode, and determine whether the area currently scanned by the laser radar is in the key area.

[0058] If yes, switch the operating mode of the laser radar from the first mode to the second mode, where the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode;

[0059] If not, the process returns to the step of controlling the laser radar to scan in the first mode and acquire point cloud data, that is, continuing to execute step S100.

[0060] It should be noted that in autonomous driving, the amount of point cloud data of LiDAR is huge, and the higher the resolution, the larger the amount of point cloud data. Current high-resolution LiDARs can usually reach 1M to several M points per second. However, most point cloud data is actually low-value background information, and the target data that really affects driving safety accounts for a very low proportion. For example: the vertical field of view of current on-board LiDARs is generally greater than 20 degrees, but during driving, only a few degrees of viewing angle in the center of the field of view can observe pedestrians, vehicles, and obstacles related to driving safety. Most of the light beams are directed into the air and the ground, and most of the point clouds generated are irrelevant to driving safety. Taking a 120-degree × 25-degree radar as an example, the field of view is 3000 degrees. 2 A car-like target occupies about 25 degrees of field of view. 2 , 20 vehicle targets are only 500 degrees 2 , accounting for 16.7% of the total field of view. Therefore, it is not necessary for the laser radar to maintain a high resolution throughout the entire field of view. Therefore, the laser radar scanning method provided in this application first uses a low-resolution mode (i.e., the resolution corresponding to the first mode) to scan and determine the key areas and non-key areas; then, during normal driving, it is determined whether the currently scanned area is in the key area, and when the currently scanned area enters the key area, it uses a high-resolution (i.e., the resolution corresponding to the second mode) scan, and continues to resume low-resolution scanning when it does not enter the key area (i.e., when it is in the non-key area). This can greatly save power consumption and computing power, and can ensure high-resolution scanning of areas that affect driving safety, thereby ensuring driving safety. Please refer to Figure 4 and Figure 5 , Figure 4 The point cloud corresponding to the normal scan (all point cloud data are kept at low resolution). Figure 5 The point cloud map obtained by the laser radar scanning provided in this application (the point cloud resolution in the key area is high, and the point cloud resolution in the non-key area is low).

[0061] To summarize, the laser radar scanning method provided in the present application includes: controlling the laser radar to scan in a first mode and obtaining point cloud data; determining key areas and non-key areas based on the point cloud data; controlling the laser radar to continue scanning in the first mode, and determining whether the area currently scanned by the laser radar is in a key area; if so, switching the working mode of the laser radar from the first mode to the second mode, the resolution corresponding to the second mode being greater than the resolution corresponding to the first mode; if not, returning to the step of controlling the laser radar to scan in the first mode and obtaining point cloud data. This application first uses a low-resolution mode (i.e., the resolution corresponding to the first mode) to scan and determine the key areas and non-key areas; then, in a normal laser radar scan, it is determined whether the currently scanned area is within the key area, and when the currently scanned area is within the key area, it is scanned using a high-resolution mode (i.e., the resolution corresponding to the second mode); when it does not enter the key area (i.e., when it is in the non-key area), it returns to resume the low-resolution scan and reacquire the point cloud data, and determines the key areas and non-key areas. In this way, a laser radar can scan a wider field of view while performing high-resolution scanning and tracking of obstacles in key areas within a small range, and low-resolution tracking of obstacles in non-key areas. In this way, on the one hand, this application can ensure high-resolution tracking of obstacles that affect driving safety; on the other hand, compared with the existing technology, this application has low requirements for hardware resources, will not increase the power consumption of the laser radar, and does not require complex calculations and processing, thereby achieving a balance between meeting the requirements of a large field of view width and effective high resolution.

[0062] Optionally, the laser radar scanning method provided in this application further includes:

[0063] After each frame of the laser radar scan is completed, the key target is re-determined.

[0064] That is, after each frame scan of the laser radar is completed, the application needs to update the key areas and non-key areas in real time, so that the key areas and non-key areas in step S200 can be updated. In this way, new key areas can be added and unqualified key areas can be removed, that is, dynamic updating can be achieved, so that the accuracy of key areas and non-key areas can be improved.

[0065] For example, the laser radar scanning method provided in this application is implemented based on laser radar, please refer to Figure 6As shown, the light beam emitted by the laser is injected into the collimating mirror 12 by the optical fiber 11, and reaches the scanning unit 15 after passing through the reflector 13 and the perforated reflector 14. The scanning unit 15 reflects the laser beam to the obstacle, and then the reflected echo of the obstacle returns to the scanning unit 15 along the original path, and then returns to the reflecting surface of the perforated reflector 14 through the scanning unit 15. Most of the reflected light is deflected by the perforated reflector 14 to the receiving lens 16 on one side, and the light spot focused by the receiving lens 16 falls on the sensor array 17 located on the receiving plate 18.

[0066] The laser radar receives an echo spot, which is focused on the photosensitive surface of the sensor array 17 through the receiving lens 16. It should be noted that the light sensor of existing laser radars is a single-point sensor, so it receives only one signal. However, the laser radar provided in this embodiment uses a sensor array 17. Therefore, when the laser radar receives an echo spot, if the spot is larger than or equal to the photosensitive surface, the number of signals obtained is equal to the number of elements in the sensor array 17. For example, if the sensor array 17 has four sensor elements 171, it can obtain four signals.

[0067] This application uses point cloud image recognition to rationally allocate pixel resources, giving high-impact obstacles related to driving safety high pixels (high resolution, i.e., second resolution) and giving low-impact obstacles such as the field of view background and low-impact obstacles low pixels (low resolution, i.e., first resolution). For example, by adding a receiving circuit and a switching circuit to the sensor array 17, the lidar can quickly switch between high-resolution and low-resolution operating states.

[0068] For example, Figure 7 As shown, the laser radar includes a receiving circuit, which includes: a sensor array 17, the sensor array 17 has at least two sensor units 171; at least two amplifiers 22, respectively connected to the at least two sensor units 171 in a one-to-one correspondence; at least two sampling circuits 25, respectively connected to the at least two amplifiers 22 in a one-to-one correspondence; and switching between the first mode and the second mode is achieved by adding a switching circuit between the at least two amplifiers 22 and the at least two sampling circuits 25.

[0069] It should be noted that Figure 7 The sensor array 17 is shown as including four sensor units 171. Thus, there are four corresponding first amplifiers 22 and four sampling circuits 25. It should be understood that the four sensor units 171 are merely examples and are not intended to limit the sensor array 17 of the present application.

[0070] Exemplarily, the switching circuit includes: a switching circuit connected between the amplifier 22 and the sampling circuit 25, configured to combine the amplified signals of at least two amplifiers 22 through the switching circuit and connect them to any one of the sampling circuits 25, or to connect the amplified signals of at least two amplifiers 22 to at least two sampling circuits 25 in a one-to-one correspondence through the switching circuit; and a controller 21 electrically connected to the switching circuit, configured to control the switching circuit so that one of the sampling circuits is turned on or each of the sampling circuits is turned on.

[0071] That is, the controller 21 can control the switch circuit to operate so that the amplified signal of each amplifier 22 is connected to one of the sampling circuits 25 after being combined; or, so that the amplified signal of each amplifier 22 is first connected to each sampling circuit 25 accordingly.

[0072] In this embodiment, optionally, the switching circuit includes: at least two first single-pole double-throw switches 23, wherein the common end of each first single-pole double-throw switch 23 is connected to each amplifier 22 in a one-to-one correspondence, and the normally open end of each first single-pole double-throw switch 23 is connected to each sampling circuit 25; a second single-pole double-throw switch 24, wherein the normally open end of the second single-pole double-throw switch 24 is connected to the normally open end of any first single-pole double-throw switch 23, the common end of the second single-pole double-throw switch 24 is connected to any sampling circuit 25, and the normally closed end of the second single-pole double-throw switch 24 is connected to the normally closed end of each first single-pole double-throw switch 23 in a combined circuit.

[0073] In this way, the controller 21 can control the number of conducting circuits of the sampling circuit by controlling the state switching of the first single-pole double-throw switch 23 and the second single-pole double-throw switch 24 .

[0074] For ease of understanding and explanation, Figure 7 The sensor array 17 shown includes four sensor units 171, which are used as an example to explain the receiving circuit and switching circuit. The received signal of the 2×2 sensor array 17 in the figure above is amplified by four independent amplifiers 22 and then input into four first single-pole double-throw switches 23 (i.e., K1, K2, K3, and K4). The normally closed terminals of the four first single-pole double-throw switches 23 are short-circuited and connected to the normally closed terminal of a second single-pole double-throw switch 24. One of the normally open terminals of the four first single-pole double-throw switches 23 is connected to the normally open terminal of a second single-pole double-throw switch 24, and the common terminal of the second single-pole double-throw switch 24 is connected to the input terminal of one of the sampling circuits 25. The normally open terminals of the remaining three first single-pole double-throw switches 23 are respectively connected to the input terminals of the remaining three sampling circuits 25.

[0075] The four first single-pole double-throw switches 23 and the one second single-pole double-throw switch 24 are all controlled by the controller 21. When low resolution is required (the resolution corresponding to the first mode), the four first single-pole double-throw switches 23 are all placed in the normally closed position, and the second single-pole double-throw switch 24 is placed in the normally closed position. The signals from the four amplifiers 22 are combined and input to one of the sampling circuits 25 (i.e., ADC1) via the second single-pole double-throw switch 24 for reception. At this time, only ADC1 is working, and the laser radar only obtains one pixel point. When high resolution is required (i.e., the resolution corresponding to the second mode), the four first single-pole double-throw switches 23 are all placed in the normally open position, and the second single-pole double-throw switch 24 is placed in the normally open position. At this time, the amplified signals from the four amplifiers 22 enter the four sampling circuits 25 respectively (i.e., ADC1, ADC2, ADC3, and ADC4 are sampled simultaneously), and the laser radar can obtain four pixels.

[0076] The first single-pole double-throw switch 23 and the second single-pole double-throw switch 24 can both be fast electronic switches with an action response time of nanoseconds, which can achieve seamless switching within the laser pulse interval time.

[0077] Wide-field-of-view lidars typically consist of multiple smaller fields of view spliced ​​together to create a wider horizontal field of view. The receiving and signal processing channels for each field of view are typically independent. By leveraging the aforementioned mode switching concept, sampling circuit resources can be shared across multiple fields of view. Optionally, when the lidar includes at least two fields of view, each field of view corresponds to a receiving circuit and a switching circuit electrically connected to the receiving circuit. The sampling circuitry within the receiving circuits corresponding to at least two fields of view is partially shared.

[0078] The following is an example of a dual field of view (such as Figure 8 As shown, Figure 8 The left and right fields of view are shown. Each of the two fields of view has a receiving circuit and a switching circuit. The structures of the receiving circuit and the switching circuit are the same as those described above and will not be repeated here. For example, the sensor array 17 also includes four sensor units 171 and the sampling circuit 25 includes four. Then, three of the sampling circuits 25 corresponding to the two fields of view can be shared (corresponding to Figure 8 The three sampling circuits 25 are outlined in dashed lines. That is, the shared portion can be allocated to any field of view as needed. Thus, the receiving circuit that receives the shared resource allocation can obtain high-pixel information (the principle is the same as the switching circuit principle and will not be repeated in this application), while the receiving circuit that does not receive the shared resource allocation maintains the original single-channel ADC sampling and outputs low-pixel information.

[0079] This application sets up a shared part so that as long as the key areas of the two fields of view do not appear at the same time, the two fields of view can share ADC resources. Similarly, three fields of view, or even more fields of view, LiDAR can also use this solution to share ADC, thereby saving hardware overhead and power consumption. It should be noted that two fields of view are only examples given for the convenience of explanation in this application. In other embodiments, the LiDAR can also include three fields of view or more.

[0080] Second embodiment

[0081] An embodiment of the present invention further provides a laser radar scanning device, comprising:

[0082] A first scanning module, used to control the laser radar to scan in a first mode and obtain point cloud data;

[0083] The first determining module is used to determine the key area and the non-key area according to the point cloud data.

[0084] The judgment module is used to control the laser radar to continue scanning in the first mode and to judge whether the area currently scanned by the laser radar is in the key area.

[0085] If so, the operating mode of the laser radar is switched from the first mode to the second mode, and the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode.

[0086] If not, return to the step of controlling the laser radar to scan in the first mode and acquiring point cloud data.

[0087] Among them, the above-mentioned device is used to execute the laser radar scanning method provided by the aforementioned first embodiment. Its implementation principle and technical effects are similar, and this application will not repeat them here.

[0088] The above modules can be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASICs), one or more digital singnal processors (DSPs), or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented by scheduling program code through a processing element, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0089] Third embodiment

[0090] Please refer to Figure 9 This embodiment further provides a computer device including a processor 510, a storage medium 520, and a bus 530. The storage medium 520 stores machine-readable instructions executable by the processor 510. When the instruction processing device is running, the processor 510 communicates with the storage medium 520 via the bus 530, and the processor 510 executes the machine-readable instructions to perform the steps of the above-mentioned method embodiment. The specific implementation methods and technical effects are similar and will not be repeated here.

[0091] Optionally, the storage medium 520 may be a USB flash drive, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0092] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, 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.

[0093] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0094] In addition, the functional units in various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or hardware plus software functional units.

[0095] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) or a processor (English: processor) to perform some steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: a USB flash drive, a mobile hard disk, a read-only memory (English: Read-Only Memory, abbreviated: ROM), a random access memory (English: Random Access Memory, abbreviated: RAM), a magnetic disk or an optical disk, and other media that can store program code.

[0096] The foregoing description is merely an optional embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

[0097] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A laser radar scanning method, characterized in that: include: Controlling the laser radar to scan in a first mode and acquire point cloud data; determining key areas and non-key areas based on the point cloud data; Controlling the laser radar to continue scanning in the first mode, and determining whether the area currently scanned by the laser radar is within the key area; If yes, switching the operating mode of the laser radar from the first mode to the second mode, wherein the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode; If not, return to the step of controlling the laser radar to scan in the first mode and acquiring point cloud data; The laser radar includes a receiving circuit, which includes: a sensor array having at least two sensor units; at least two amplifiers, each connected to the at least two sensor units in a one-to-one correspondence; at least two sampling circuits, each connected to the at least two amplifiers in a one-to-one correspondence; and switching between the first mode and the second mode is achieved by adding a switching circuit between the at least two amplifiers and the at least two sampling circuits. The switching circuit includes: a switch circuit connected between the amplifier and the sampling circuit, configured to connect the amplified signals of the at least two amplifiers to any one of the sampling circuits after being combined through the switch circuit, or to connect the amplified signals of the at least two amplifiers to the at least two sampling circuits in a one-to-one correspondence through the switch circuit; a controller electrically connected to the switch circuit, configured to control the switch circuit to turn on one of the sampling circuits or all of the sampling circuits; The switch circuit includes: at least two first single-pole double-throw switches, the common end of each first single-pole double-throw switch is connected to each amplifier in a one-to-one correspondence, and the normally open end of each first single-pole double-throw switch is connected to each sampling circuit; a second single-pole double-throw switch, wherein the normally-open end of the second single-pole double-throw switch is connected to the normally-open end of any one of the first single-pole double-throw switches, the common end of the second single-pole double-throw switch is connected to any one of the sampling circuits, and the normally-closed end of the second single-pole double-throw switch is connected to the normally-closed end of each of the first single-pole double-throw switches after being combined.

2. The laser radar scanning method according to claim 1, characterized in that: The laser radar is installed on the target vehicle and is used to scan the external environment of the target vehicle. The determining of key areas and non-key areas based on the point cloud data includes: Determining a ground plane area where the target vehicle is located based on the point cloud data, and screening out obstacles located above the ground plane area based on the ground plane area; Determining a target to be selected from the obstacles based on at least two consecutive frames of point cloud data, wherein the target to be selected is an obstacle having a point cloud quantity greater than a preset quantity in at least two consecutive frames of point cloud data; A key target is determined according to the moving direction of the candidate target and the moving direction of the target car, and the area where the key target is located is the key area.

3. The laser radar scanning method according to claim 2, characterized in that: The determining of the key target according to the movement direction of the candidate target and the movement direction of the target vehicle includes: Obtaining the moving direction of the target to be selected and the moving direction of the target car; Analyzing whether the moving direction of the target to be selected and the moving direction of the target car intersect; If so, the target to be selected is determined to be a key target; If not, it is determined that the target to be selected is a non-key target.

4. The laser radar scanning method according to claim 3, characterized in that: The obtaining of the movement direction of the target to be selected and the movement direction of the target vehicle includes: Calculating the movement direction of the target to be selected based on at least two consecutive frames of point cloud data; The moving direction of the target vehicle is determined according to the direction of the central axis of the field of view of the laser radar.

5. The laser radar scanning method according to claim 3, characterized in that: The method further includes: re-determining the key target after each frame scan of the laser radar is completed.

6. The laser radar scanning method according to claim 1, characterized in that: When the laser radar includes at least two fields of view, each field of view corresponds to a receiving circuit and a switching circuit electrically connected to the receiving circuit, wherein the sampling circuit portion in the receiving circuits corresponding to the at least two fields of view is shared.

7. The laser radar scanning method according to claim 6, characterized in that: The number of the sampling circuits corresponding to the at least two fields of view is equal to the number of the sensor units corresponding to each field of view.

8. A laser radar scanning device, used to execute the laser radar scanning method according to any one of claims 1 to 7, characterized in that: include: A first scanning module, used to control the laser radar to scan in a first mode and obtain point cloud data; A first determining module is used to determine key areas and non-key areas based on the point cloud data; a judgment module, configured to control the laser radar to continue scanning in the first mode, and to judge whether the area currently scanned by the laser radar is within the key area; If yes, switching the operating mode of the laser radar from the first mode to the second mode, wherein the resolution corresponding to the second mode is greater than the resolution corresponding to the first mode; If not, return to the step of controlling the laser radar to scan in the first mode and acquiring point cloud data.

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