Variable field of view laser radar scanning system, method, apparatus, and storage medium

Abstract

This application provides a variable field-of-view lidar scanning system, method, device, and storage medium. The system includes a laser transceiver, a first scanning element, and a second scanning element. The first scanning element is disposed downstream of the optical path of the laser transceiver and is used to reflect the detection beam emitted by the laser transceiver in a first preset direction to obtain a reflected beam. Every preset time interval, the deflection angle of the first scanning element changes so that the detection beam is reflected to different angles. The second scanning element is disposed downstream of the reflected optical path of the first scanning element and is used to expand the reflected beam in a second preset direction to scan the target object. This application achieves two-dimensional deflection and large field-of-view scanning of the detection beam through the coordinated operation of the first and second scanning elements, and gives the scanning trajectory a high degree of controllability. By adjusting the preset deflection angle, it flexibly adapts to diverse detection needs, improving the system's environmental adaptability and detection accuracy.

Description

Technical Field

[0001] This application belongs to the field of lidar scanning technology, and relates to a variable field-of-view lidar scanning system, method, device and storage medium. Background Technology

[0002] LiDAR, as an active photoelectric detection system, accurately calculates distance by emitting laser pulses and detecting the backscattered echoes of targets. Scanning LiDAR typically uses linear array detectors in conjunction with scanning mechanisms to achieve wide-area horizontal scanning. With its wide field of view, high precision, excellent resolution, and strong anti-interference capabilities, it is widely used in autonomous driving and intelligent sensing fields. However, existing solutions have limitations: the vertical field of view of traditional two-dimensional scanning is fixed by optical components and cannot be dynamically adjusted according to the environment, leading to missed detections or data redundancy in complex scenarios; moreover, the vertical angular resolution is limited by hardware parameters, making flexible optimization difficult. Therefore, how to maintain a wide horizontal field of view while achieving flexible expansion and adjustment of the vertical field of view, and also enabling long-range detection, is a key challenge in current technological development. Summary of the Invention

[0003] This application provides a variable field-of-view lidar scanning system, method, apparatus, and storage medium for flexibly expanding the scanning field of view while maintaining a horizontally wide field of view.

[0004] In a first aspect, this application provides a variable field-of-view lidar scanning system, the system comprising: a laser transceiver, a first scanning element, and a second scanning element, wherein the first scanning element is disposed downstream of the optical path of the laser transceiver and is used to reflect the detection beam emitted by the laser transceiver in a first preset direction to obtain a reflected beam, wherein the deflection angle of the first scanning element changes every preset time interval so that the detection beam is reflected to different angles; the second scanning element is disposed downstream of the reflected optical path of the first scanning element and is used to spread the reflected beam in a second preset direction to scan the target object.

[0005] In this application, the cooperation of the first scanning element and the second scanning element enables the deflection and scanning of the detection beam in two dimensions (the first preset direction and the second preset direction), effectively expanding the scanning field of view of a single laser beam and realizing a large-scale, two-dimensional coverage scan of the target object. The cooperation of the first scanning element and the second scanning element makes the scanning trajectory of the detection beam controllable. By adjusting the deflection angle and time interval of the first scanning element, different scanning requirements can be flexibly adapted, thereby improving the scanning system's adaptability to complex environments and detection accuracy.

[0006] In one implementation of the first aspect, the first scanning element includes: a swing shaft and a swing mirror that reciprocates around the swing shaft, wherein the detection beam is reflected in the first preset direction by the swing mirror which is fixed at a preset deflection angle.

[0007] In one implementation of the first aspect, the second scanning element includes a rotation axis and a polyhedral mirror that rotates continuously around the rotation axis. The polyhedral mirror is used to expand the reflected light beam in the second preset direction to scan the target object. The polyhedral mirror includes multiple reflecting surfaces, each of which is parallel to the rotation axis.

[0008] In one implementation of the first aspect, the number of preset deflection angles of the inner mirror of the first scanning element is less than or equal to the number of inner reflective surfaces of the second scanning element.

[0009] In one implementation of the first aspect, the laser transceiver includes a transmitter and a receiver, wherein the transmitter is used to emit the probe beam, and the receiver is used to receive the echo signal reflected from the probe beam projected onto the target object.

[0010] In one implementation of the first aspect, the transmitting end employs a laser emitter arranged in a linear array, and the receiving end employs a receiving detector arranged in a linear array.

[0011] In one implementation of the first aspect, the system further includes: a collimating lens disposed between the transmitting end and the first scanning element, for converting the probe beam emitted by the transmitting end from a diverging beam into a parallel beam before emitting it to the first scanning element.

[0012] Secondly, this application provides a variable field-of-view lidar scanning method, the method comprising: S1, acquiring a detection beam; S2, sending the detection beam to a first scanning element fixed at a preset deflection angle, the first scanning element reflecting the detection beam in a first preset direction to obtain a reflected beam; S3, reflecting the reflected beam to a second scanning element, the second scanning element expanding the reflected beam in a second preset direction to scan a target object; S4, determining the point cloud field of view corresponding to the preset deflection angle based on the echo signal after scanning the target object; S5, adjusting the preset deflection angle of the first scanning element to obtain an adjusted preset deflection angle; S6, repeating steps S1 to S4 to obtain the point cloud field of view corresponding to the adjusted preset deflection angle; S7, stitching together the point cloud fields of view corresponding to multiple preset deflection angles to obtain a target point cloud field of view.

[0013] Thirdly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the variable field-of-view lidar scanning method described in the second aspect of embodiments of this application.

[0014] Fourthly, embodiments of this application provide an electronic device, the electronic device comprising: a memory storing a computer program; and a processor communicatively connected to the memory, which executes the variable field-of-view lidar scanning method described in the second aspect of embodiments of this application when the computer program is invoked.

[0015] As described above, the variable field-of-view lidar scanning system, method, device, and storage medium of this application have the following beneficial effects:

[0016] 1) In this application, the deflection and scanning of the detection beam in two dimensions (first preset direction and second preset direction) are realized through the cooperation of the first scanning element and the second scanning element, thereby effectively expanding the scanning field of view of the single laser beam and realizing a large-scale, two-dimensional coverage scan of the target object; the cooperation of the first scanning element and the second scanning element makes the scanning trajectory of the detection beam controllable, and can flexibly adapt to different scanning requirements by adjusting the deflection angle and time interval of the first scanning element, thereby improving the adaptability of the scanning system to complex environments and the detection accuracy.

[0017] 2) In this embodiment, when the number of preset deflection angles is less than the number of reflective surfaces, it means that the same preset deflection angle will be reused by multiple reflective surfaces. This increases the number of times the reflected beam scans a specific angle area per unit time, significantly improving the point cloud refresh rate without changing the device rotation speed. This is suitable for scenarios requiring high-frequency monitoring and rapid response in specific key areas. When the number of preset deflection angles equals the number of reflective surfaces, each reflective surface corresponds to a unique preset deflection angle. This fully utilizes the rotation cycle of the rotating mirror, enabling the stitching of more different angle fields of view at once, greatly expanding the scanning field of view, and increasing the coverage density of the field of view point cloud. This is suitable for scenarios requiring large-scale detection and acquisition of richer environmental information. This embodiment breaks the limitations of the traditional single scanning mode. Through a simple quantity matching relationship, the scanning performance (field size vs. refresh rate) can be flexibly reconstructed, enabling the lidar to adapt to more diverse application scenario requirements.

[0018] 3) In this application, the divergent detection beam emitted from the transmitting end is collimated and shaped by a collimating lens, and then converted into a parallel beam before being incident on the first scanning element, thereby achieving precise control of the angle characteristics of the incident beam; by collimating, the direction consistency of the incident beam is ensured, which can ensure that the detection beam is incident at a certain angle, so that the reflected beam can be deflected and scanned strictly according to the preset angle, thereby ensuring the accuracy and consistency of the scanning angle and effectively avoiding problems such as field distortion or scanning overlap caused by beam divergence. Attached Figure Description

[0019] Figure 1 The diagram shown is a structural diagram of a variable field-of-view lidar scanning system provided in an embodiment of this application.

[0020] Figure 2 The diagram shown is a structural diagram of the first scanning element provided in an embodiment of this application.

[0021] Figure 3 The diagram shown is a structural diagram of the second scanning element provided in an embodiment of this application.

[0022] Figure 4 The diagram shown is a structural diagram of a laser transceiver device provided in an embodiment of this application.

[0023] Figure 5 The diagram shown is a structural diagram of a laser transceiver device based on beam collimation processing provided in an embodiment of this application.

[0024] Figure 6 The diagram shown is an overall structural diagram of the variable field-of-view lidar scanning system provided in an embodiment of this application.

[0025] Figure 7 The diagram shown is an optical path diagram of a variable field-of-view lidar scanning system provided in an embodiment of this application.

[0026] Figure 8 The diagram shown illustrates the formation of a variable field of view as provided in an embodiment of this application.

[0027] Figure 9 The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed first deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror rotates to the first scanning position point.

[0028] Figure 10 The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed first deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror is rotated to the second scanning position point.

[0029] Figure 11The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed second deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror rotates to the first scanning position point.

[0030] Figure 12 The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed second deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror rotates to the second scanning position point.

[0031] Figure 13 The diagram shown is an example of how different field of view angles are obtained by controlling the preset deflection angle of the oscillating mirror according to an embodiment of this application.

[0032] Figure 14 The flowchart shown is a variable field-of-view lidar scanning method provided in an embodiment of this application.

[0033] Figure 15 The diagram shown is a structural diagram of an electronic device provided in an embodiment of this application.

[0034] Component designation explanation

[0035] 100 Variable field of view lidar scanning system 131 Rotation axis 110 Laser transceiver devices 132 Polyhedral rotating mirror 111 transmitter S1~S7 step 112 receiver 20 electronic devices 113 collimating lens 21 processor 120 First scanning element 22 Non-volatile storage media 121 Swing axis 23 System bus 122 Mirror 24 Internal memory 130 Second scanning element 25 Network interface Detailed Implementation

[0036] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0037] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. Therefore, the drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0038] like Figure 1 As shown in the figure, this application provides a structural diagram of a variable field of view lidar scanning system. The variable field of view lidar scanning system 100 includes: a laser transceiver device 110, a first scanning element 120, and a second scanning element 130.

[0039] The first scanning element is disposed downstream of the optical path of the laser transceiver and is used to reflect the probe beam emitted by the laser transceiver in a first preset direction to obtain a reflected beam.

[0040] In this process, at preset time intervals, the deflection angle of the first scanning element changes so that the detection beam is reflected to different angles.

[0041] For example, the first scanning element is a vertical scanning element, and the first preset direction is a vertical direction, used to reflect the probe beam emitted by the laser transceiver in a vertical direction.

[0042] It should be noted that the first scanning element listed in the above example is a vertical scanning element, and the first preset direction is a vertical direction only for illustrative purposes. In actual applications, the first scanning element can be determined to be any other scanning element with any suitable scanning angle, and the first preset direction can be determined to be any other suitable direction, based on the specific application scenario. This application does not impose any restrictions on this.

[0043] The second scanning element is disposed downstream of the reflected light path of the first scanning element, and is used to spread the reflected light beam in a second preset direction to scan the target object.

[0044] For example, the second scanning element is a horizontal scanning element, and the second preset direction is a horizontal direction, used to spread the reflected beam in the horizontal direction to scan the target object.

[0045] For example, at preset time intervals, the deflection angle of the first scanning element is 30°, 50°, or 60°, etc.

[0046] The steps for determining the preset time interval are as follows:

[0047] In this application, it is assumed that the number of reflecting surfaces N of the second scanning element and the rotational angular velocity are... Horizontal scanning angle range corresponding to a single reflective surface And the preset angle number M and maximum swing amplitude of the first scanning element. Angle control accuracy These factors together determine the scanning field of view and resolution characteristics of the system.

[0048] Let the required horizontal field of view of the system be... Then, the horizontal scanning angle range that a single reflective surface needs to cover It should be no less than Because the mechanical rotation angle of the reflecting surface is twice the beam scanning angle when the beam is scanned by the reflecting surface, the effective mechanical scanning angle range of the reflecting surface is limited. Should meet .

[0049] Let the maximum vertical field of view required by the system be... The maximum mechanical oscillation amplitude of the vertical scanning element. Should meet When the system needs to implement When covering the vertical field of view, the first scanning element needs to traverse all M preset angles, and the total span of the M preset angles should be equal to... .

[0050] Assume the system requires the vertical point cloud layer height to not exceed a certain value at the maximum detection distance R. The angle control accuracy of the vertical scanning element. Should meet In engineering implementation, the resolution of the angle sensor used to provide feedback on the position of the vertical scanning element is crucial. It should at least meet , where K is the control margin coefficient, which is usually taken as 4 to 10.

[0051] Rotational angular velocity of the second scanning element Determines the system's frame rate For a horizontal scanning element with N reflective surfaces, scanning of all N reflective surfaces is completed in one rotation, hence the system frame rate... and satisfy: .

[0052] In this embodiment of the application, taking the first scanning element as a vertical scanning element and the second scanning element as a horizontal scanning element as an example, the optical path diagram and working process of the variable field of view lidar scanning system are described in detail.

[0053] In this embodiment, it is assumed that the system requires a horizontal field of view. The maximum vertical field of view is 120°. The vertical field of view of the incident scanning system light is 90°. The angle is 25°, the maximum detection distance R is 200m, and the allowable vertical point cloud layering height is... It is 17.5cm.

[0054] Depend on = 120° gives the range of horizontal scanning angles that a single reflective surface needs to cover. °, then the effective mechanical scanning angle range of the reflecting surface °.

[0055] Depend on =90° gives the maximum mechanical oscillation amplitude of the vertical scanning element. °.

[0056] From R=200m, The angle control accuracy of the vertical scanning element can be obtained from 0.175m. This translates to an angle constraint of 0.05°. Taking a control margin coefficient K=5, the angle sensor resolution... It should be better than 0.01°.

[0057] In this embodiment, the horizontal scanning element uses a polyhedral rotating mirror with N = 4 reflective surfaces. Let the required frame rate of the system be... If the frequency is 10Hz, then the rotational angular velocity of the mirror is... The corresponding rotational speed is The time it takes for the rotating mirror to complete one revolution. The time window occupied by each reflective surface .

[0058] The total rotation angle between adjacent reflecting surfaces of the rotating mirror is 360° / N = 90°, of which the effective mechanical scanning angle is... ° corresponds to the imaging window, and the remaining 30° corresponds to the transition region between the reflecting surfaces. From this, the duty cycle of the imaging window can be obtained. ,

[0059] Imaging window duration Window switching duration .

[0060] Vertical scanning elements need to be in Within a certain time, the transition from the current preset deflection angle to the next preset angle is completed, with a transition amplitude of [value missing]. Where M is the number of preset angles. In this embodiment, M is 4, so the interval between adjacent preset deflection angles is 37.5° / 3 = 12.5°, and the full-amplitude response time of the vertical scanning element must be less than 8.3ms.

[0061] It should be noted that the deflection angle of 30° and the preset time interval listed in the above example are merely illustrative examples, and this application does not impose any restrictions on the specific values ​​of the deflection angle and the preset time interval.

[0062] This application provides a variable field-of-view lidar scanning system. By cooperating with a first scanning element (which changes the deflection angle) and a second scanning element (which expands the scanning), the detection beam is deflected and scanned in two dimensions (a first preset direction and a second preset direction), thereby effectively expanding the scanning field of view of a single laser beam and achieving large-area, two-dimensional coverage scanning of the target object. The cooperation between the first and second scanning elements makes the scanning trajectory of the detection beam controllable. By adjusting the deflection angle and time interval of the first scanning element, different scanning requirements can be flexibly adapted, thereby improving the scanning system's adaptability to complex environments and detection accuracy.

[0063] like Figure 2 As shown in the figure, this application provides a structural diagram of a first scanning element 120, which includes: a swing shaft 121 and a swing mirror 122 that reciprocates around the swing shaft.

[0064] The detection beam is reflected in the first preset direction by the pendulum mirror fixed at a preset deflection angle.

[0065] For example, the preset deflection angle of the pendulum mirror can be changed by rotating the pendulum axis.

[0066] like Figure 3 As shown in the figure, this application provides a structural diagram of a second scanning element 130, which includes a rotation axis 131 and a polyhedral rotating mirror 132 that rotates continuously around the rotation axis.

[0067] The polyhedral rotating mirror is used to expand the reflected beam in the second preset direction to scan the target object. The polyhedral rotating mirror includes multiple reflecting surfaces, each of which is parallel to the rotation axis.

[0068] For example, a polyhedral rotating mirror can be a cuboid, a hexagonal prism, or the like. If the polyhedral rotating mirror is a cuboid, it has 4 reflecting surfaces; if it is a hexagonal prism, it has 6 reflecting surfaces.

[0069] It should be noted that the polyhedral rotating mirrors listed above, which are cuboids and hexagonal prisms, are only used as examples. In practical applications, any other suitable polyhedral rotating mirror can be selected based on specific application requirements, and this application does not impose any restrictions on this.

[0070] In some embodiments, the number of preset deflection angles of the inner mirror of the first scanning element is less than or equal to the number of inner reflective surfaces of the second scanning element.

[0071] For example, when the number of preset deflection angles of the tilting mirror in the first scanning element is less than the number of reflecting surfaces in the second scanning element (assuming the preset deflection angles can be 30° or 40°), the polyhedral rotating mirror in the second scanning element has four reflecting surfaces. For instance, the tilting mirror fixed at 30° corresponds to the first and second reflecting surfaces of the tetrahedral rotating mirror, and the tilting mirror fixed at 40° corresponds to the third and fourth reflecting surfaces of the tetrahedral rotating mirror, enabling the stitching of two long strip-shaped fields of view. Furthermore, a higher refresh rate, under the condition that the driving frequency or rotation speed of the rotating mirror and the tilting mirror remains unchanged, can achieve a more flexible field of view and point cloud refresh rate.

[0072] For example, when the number of preset deflection angles of the tilting mirrors in the first scanning element is equal to the number of reflecting surfaces in the second scanning element, assuming the preset deflection angles can be 15°, 30°, 40°, and 60°, the polyhedral rotating mirror in the second scanning element has four reflecting surfaces. For instance, the tilting mirror fixed at 15° corresponds to the first reflecting surface of the tetrahedral rotating mirror; the tilting mirror fixed at 30° corresponds to the second reflecting surface of the tetrahedral rotating mirror; the tilting mirror fixed at 40° corresponds to the third reflecting surface of the tetrahedral rotating mirror; and the tilting mirror fixed at 60° corresponds to the fourth reflecting surface of the tetrahedral rotating mirror, thus enabling the stitching of four long strip-shaped fields of view.

[0073] In this embodiment, when the number of preset deflection angles is less than the number of reflective surfaces, it means that the same preset deflection angle will be reused by multiple reflective surfaces. This multiplies the number of times the reflected beam scans a specific angle region per unit time, significantly improving the point cloud refresh rate without changing the device rotation speed. This is suitable for scenarios requiring high-frequency monitoring and rapid response in specific key areas. When the number of preset deflection angles equals the number of reflective surfaces, each reflective surface corresponds to a unique preset deflection angle. This fully utilizes the rotation cycle of the rotating mirror, enabling the stitching of more different angle fields of view at once, greatly expanding the scanning field of view, and increasing the coverage density of the field of view point cloud. This is suitable for scenarios requiring large-scale detection and acquisition of richer environmental information. This embodiment breaks the limitations of the traditional single scanning mode. Through a simple quantity matching relationship, the scanning performance (field size vs. refresh rate) can be flexibly reconstructed, enabling the lidar to adapt to more diverse application scenario requirements.

[0074] like Figure 4 As shown in the figure, this application provides a structural diagram of a laser transceiver device, which includes a transmitter 111 and a receiver 112.

[0075] The transmitting end is used to emit the detection beam.

[0076] The receiving end is used to receive the echo signal reflected from the detection beam projected onto the target object.

[0077] In some embodiments, the transmitting end employs a laser emitter arranged in a linear array, and the receiving end employs a receiving detector arranged in a linear array.

[0078] This application employs a linear array of laser transmitters and receiver detectors. Compared to single-point scanning (detecting only one point at a time), the linear array allows the system to process information from multiple points in a column (or row) simultaneously during a single transmission and reception, achieving a "line-for-point" detection method. This allows for the acquisition of more field-of-view point cloud data within the same timeframe. Combined with a multi-faceted rotating mirror that continuously rotates around a rotation axis within the second scanning element, the linear array scheme can fill the entire field of view extremely quickly, making it easier to achieve high frame rate real-time scanning.

[0079] like Figure 5 As shown in the figure, this application embodiment provides a structural diagram of a laser transceiver device based on beam collimation processing. The system further includes a collimating lens 113.

[0080] The collimating lens is disposed between the transmitting end and the first scanning element, and is used to convert the probe beam emitted by the transmitting end from a divergent beam into a parallel beam before emitting it to the first scanning element.

[0081] In this embodiment, a collimating lens is placed between the transmitting end and the first scanning element. The probe beam emitted by the transmitting end naturally has a certain divergence angle. As the transmission distance increases, the spot size expands rapidly, leading to a sharp decrease in energy density. The collimating lens compresses the divergent beam into a parallel beam, which can greatly reduce the divergence of the beam during transmission. The collimating lens collimates and shapes the divergent probe beam emitted by the transmitting end, converting it into a parallel beam before it is incident on the first scanning element, thereby achieving precise control of the angle characteristics of the incident beam. By ensuring the direction consistency of the incident beam through collimation processing, it can be ensured that the probe beam is incident at a certain angle, so that the reflected beam can be deflected and scanned strictly according to the preset angle, thereby ensuring the accuracy and consistency of the scanning angle and effectively avoiding problems such as field distortion or scanning overlap caused by beam divergence.

[0082] like Figure 6 As shown in the figure, this application provides an overall structural diagram of a variable field-of-view lidar scanning system.

[0083] It should be noted that, Figure 6 The various components or structures in the above Figures 1 to 5 The above has already been explained in detail, and this application will not repeat it here.

[0084] like Figure 7As shown in the figure, this application provides an optical path diagram of a variable field-of-view lidar scanning system, including: a laser transceiver module, a vertical scanning element (a tilting mirror, rotating along the z-axis in the figure, the rotation direction is marked), and a horizontal scanning element (a rotating mirror, rotating along the y-axis in the figure, the rotation direction is marked). The laser transceiver includes a linear array of laser emitters and corresponding receiver detectors, used to generate a probe beam and receive echo signals. The vertical scanning element is located downstream of the optical path of the laser transceiver module and is a tilting mirror that can reciprocate around a tilting axis, used to deflect the probe beam vertically. The horizontal scanning element is located downstream of the reflected optical path of the vertical scanning element and is a polyhedral rotating mirror that can continuously rotate around a rotation axis, used to expand and scan the vertically deflected reflected beam in the horizontal direction.

[0085] The scanning system, which consists of a swing mirror and a polyhedral rotating mirror, scans the horizontal field of view by rotating the mirror and changes the position of the scanning plane in the vertical field of view by changing the preset deflection angle of the swing mirror, thus stitching together the complete target field of view.

[0086] For example, the horizontal scanning element has four reflective surfaces, each of which is arranged parallel to the rotation axis of the horizontal scanning element. During the rotation of the horizontal scanning element, each reflective surface corresponds to a fixed time window, within which the incident light beam is reflected into the target space and the target object in the target space is scanned to form a horizontal scanning trajectory.

[0087] For example, the vertical scanning element has four preset angular positions. The vertical scanning element remains stationary at one of these preset angular positions within each time window, allowing the probe beam to be reflected onto a specific reflective surface of the horizontal scanning element within that time window, and subsequently projected onto a specific vertical angular partition in the target space. By sequentially assigning the four time windows corresponding to the four reflective surfaces to the four preset angular positions, temporal coverage of multiple angular partitions in the vertical direction is achieved.

[0088] Depend on Figure 7 It is known that the probe beam originates from the laser transceiver and, after passing through the collimating lens, is reflected successively by the vertical and horizontal scanning elements to complete the scanning of the entire field of view. The horizontal scanning element (polyhedral rotating mirror) has N=4 reflecting surfaces, and correspondingly, the vertical scanning element (oscillating mirror) has M=4 preset angles. The reflecting surfaces numbered 1234 of the horizontal scanning element and the 1234 preset angles of the vertical scanning element correspond to the 1234 scanning fields of view at the scanning plane position.

[0089] like Figure 8 As shown in the figure, this application embodiment provides a schematic diagram of the formation of a variable field of view. Figure 8The demonstration shows how a single-line point cloud formed by a linear array is scanned into a rectangular field of view (taking a 120° x 25° field of view angle as an example) 1234 by the probe beam emitted by the laser transceiver device, the oscillation of the vertical scanning element, and the rotation of the horizontal scanning element. Finally, the field of view is stitched together to form a complete field of view (when stitching the 1234 field of view, there is partial overlap in the vertical direction to achieve a 120° x 90° field of view angle as an example).

[0090] exist Figure 8 In the left-hand image, the rotating mirror can scan a 2x° horizontal field of view for every x° rotation. The scanning method is linear array exposure per angle. The black vertical column of dots in the image represents the point cloud of the current time slot exposure. The light gray dots in the image represent the point cloud of the historical time slot exposure. As the rotating mirror rotates, it scans the entire horizontal field of view, and the point cloud is gradually exposed, accumulating into a complete 120°x25° field of view.

[0091] like Figure 8 In the image on the right, after obtaining a 120°x25° field of view, the tilting mirror changes the deflection angle to change the vertical position of the next 120°x25° field of view (e.g., from 1 to 2); by stitching together four 120°x25° fields of view, a complete frame is obtained.

[0092] like Figure 9 and Figure 10 As shown, Figure 9 The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed first deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror rotates to the first scanning position point. Figure 10 The diagram shows the change in the position of the scanning point cloud when the tilting mirror is at a fixed first deflection angle during the scanning process provided in the embodiment of this application, and the rotating mirror is rotated to the second scanning position point.

[0093] Specifically, the horizontal coordinates of the point cloud scan lines on the reflecting surface (See top view) and vertical coordinates (See main view) Rotation angle of the horizontal scanning element Rotation angle of vertical scanning element The vertical field of view of the incident light (symmetrically distributed along the y-axis). The distance Z between the object being measured and the reflecting surface of the horizontal scanning element determines the optical path distance a from the reflecting surface of the rotating mirror to the reflecting surface of the tilting mirror, satisfying the following:

[0094]

[0095]

[0096] Among them, Figure 9 and Figure 10 In the middle, the rotation angle of the vertical scanning element is .and Figure 9 The rotation angle of the transfer mirror is less than Figure 10 The angle of rotation of the transfer mirror.

[0097] like Figure 11 and Figure 12 As shown in the figure, this application embodiment provides a schematic diagram of the influence of the rotation of the rotating mirror and the angle switching of the tilting mirror on the position of the scanned point cloud during the scanning process.

[0098] Figure 11 and Figure 12 This indicates that after obtaining a 120° x 25° field of view, the tilting mirror changes its deflection angle, which is... Change the position of the next 120° x 25° field of view in the vertical direction (e.g., from 1 to 2), and stitch together 4 120° x 25° fields of view to obtain a complete frame.

[0099] During the scanning process of the second 120°x25° field of view, Figure 11 The rotation angle of the transfer mirror is less than Figure 12 The angle of rotation of the transfer mirror.

[0100] like Figure 13 As shown, Figure 13 This diagram illustrates how different field of view angles can be obtained by controlling the combination of preset deflection angles of the mirror.

[0101] in, Figure 13 The left figure shows the scanning fields of view corresponding to two preset deflection angles of the oscillating mirror. Scanning fields of view 1 and 4 are obtained at the same preset deflection angle of the oscillating mirror, while scanning fields of view 2 and 3 are obtained at another preset deflection angle of the oscillating mirror.

[0102] Figure 13 The right figure shows the scanning fields of view corresponding to the four preset deflection angles of the oscillating mirror. Due to the preset deflection angles of the oscillating mirror, there is overlap between the four scanning fields of view.

[0103] By controlling the preset deflection angle of the tilting mirror, different sizes of field of view can be achieved by stitching together, and different full field of view refresh rates can be achieved under the same mirror rotation speed or tilting mirror angle switching frequency.

[0104] like Figure 14 As shown, this application provides a flowchart of a variable field-of-view lidar scanning method. Figure 14 As shown, the variable field-of-view lidar scanning method provided in this application includes the following steps S1 to S7.

[0105] S1, acquire the probe beam.

[0106] S2, the detection beam is sent to a first scanning element fixed at a preset deflection angle, and the first scanning element reflects the detection beam in a first preset direction to obtain a reflected beam.

[0107] S3, the reflected beam is reflected to the second scanning element, and the second scanning element expands the reflected beam in a second preset direction to scan the target object.

[0108] S4, determine the point cloud field of view corresponding to the preset deflection angle based on the echo signal after scanning the target object.

[0109] S5, adjust the preset deflection angle of the first scanning element to obtain the adjusted preset deflection angle.

[0110] S6. Repeat steps S1 to S4 above to obtain the point cloud field of view corresponding to the adjusted preset deflection angle.

[0111] S7 stitches together the point cloud fields of view corresponding to multiple preset deflection angles to obtain the target point cloud field of view.

[0112] The scope of protection of the variable field-of-view lidar scanning method described in this application is not limited to the execution order of the steps listed in this embodiment. Any solution implemented by adding, subtracting, or replacing steps in the prior art based on the principles of this application is included within the scope of protection of this application.

[0113] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, or methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of modules / units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or units may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of apparatuses or modules or units may be electrical, mechanical, or other forms.

[0114] The modules / units described as separate components may or may not be physically separate. The components shown as modules / units may or may not be physical modules; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules / units can be selected to achieve the objectives of the embodiments of this application, depending on actual needs. For example, the functional modules / units in the various embodiments of this application may be integrated into one processing module, or each module / unit may exist physically separately, or two or more modules / units may be integrated into one module / unit.

[0115] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0116] This application also provides an electronic device. Figure 15 The diagram shown is a structural schematic of an electronic device 20 in one embodiment of this application. The variable field-of-view lidar scanning method provided in this embodiment can be applied to… Figure 15 The electronic device 20 shown is an example, but not limited to it. For example... Figure 15 As shown, the electronic device 20 includes a processor 21, a memory, a system bus 23, and a network interface 25. The memory may include a non-volatile storage medium 22 and internal memory 24.

[0117] The non-volatile storage medium 22 can store an operating system and a computer program. The computer program includes program instructions that, when executed, cause the processor to perform any of the variable field-of-view lidar scanning methods provided in the embodiments of this application.

[0118] The processor provides computing and control capabilities, supporting the operation of the entire computer device.

[0119] The internal memory 24 provides an environment for the execution of computer programs in non-volatile storage media. When the computer program is executed by the processor, it enables the processor to execute any of the variable field-of-view lidar scanning methods provided in the embodiments of this application.

[0120] The network interface 25 is used for network communication, such as sending assigned tasks. Those skilled in the art will understand that... Figure 2 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0121] It should be understood that processor 21 can be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among these, the general-purpose processor can be a microprocessor or any conventional processor.

[0122] The electronic device 20 in this application embodiment may include terminal devices such as tablet computers, laptop computers, mobile phones, supercomputers, and smart wearable devices. It can also be applied to databases, servers, and service response systems based on terminal artificial intelligence. This application embodiment does not impose any restrictions on the specific type of electronic device.

[0123] For example, electronic devices can be stations (STAION, ST) in WLANs, cellular phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, handheld devices with wireless communication capabilities, computing devices or other processing devices connected to a wireless modem, computers, laptops, handheld communication devices, handheld computing devices, and / or other devices for communicating over wireless systems, as well as next-generation communication systems, such as mobile terminals in 5G networks, mobile terminals in future evolved Public Land Mobile Networks (PLMNs), or mobile terminals in future evolved Non-terrestrial Networks (NTNs).

[0124] This application also provides a computer-readable storage medium. Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing a processor. The program can be stored in a computer-readable storage medium, which is a non-transitory medium, such as random access memory, read-only memory, flash memory, hard disk, solid-state drive, magnetic tape, floppy disk, optical disk, and any combination thereof. The storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disc (DVD)), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0125] This application embodiment may also provide a computer program product comprising one or more computer instructions. When the computer instructions are loaded and executed on a computing device, all or part of the processes or functions described in this application embodiment are generated. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means.

[0126] When the computer program product is executed by a computer, the computer performs the method described in the foregoing method embodiments. The computer program product can be a software installation package; when the foregoing method is required, the computer program product can be downloaded and executed on the computer.

[0127] The descriptions of the processes or structures corresponding to the above figures each have their own emphasis. For parts of a process or structure that are not described in detail, please refer to the relevant descriptions of other processes or structures.

[0128] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A variable field-of-view lidar scanning system, characterized in that, The system includes: a laser transceiver, a first scanning element, and a second scanning element. The first scanning element is disposed downstream of the optical path of the laser transceiver and is used to reflect the probe beam emitted by the laser transceiver in a first preset direction to obtain a reflected beam. The deflection angle of the first scanning element changes every preset time interval so that the probe beam is reflected to different angles. The second scanning element is disposed downstream of the reflected light path of the first scanning element, and is used to spread the reflected light beam in a second preset direction to scan the target object.

2. The system according to claim 1, characterized in that, The first scanning element includes: a swing shaft and a swing mirror that reciprocates around the swing shaft, wherein the detection beam is reflected in the first preset direction by the swing mirror which is fixed at a preset deflection angle.

3. The system according to claim 1, characterized in that, The second scanning element includes a rotating shaft and a polyhedral rotating mirror that rotates continuously around the rotating shaft. The polyhedral rotating mirror is used to spread the reflected light beam in the second preset direction to scan the target object. The polyhedral rotating mirror includes multiple reflecting surfaces, each of which is parallel to the rotating shaft.

4. The system according to claim 1, characterized in that, The laser transceiver includes a transmitter and a receiver. The transmitting end is used to emit the detection beam; The receiving end is used to receive the echo signal reflected from the detection beam projected onto the target object.

5. The system according to claim 4, characterized in that, The transmitting end uses a laser emitter arranged in a linear array, and the receiving end uses a receiver detector arranged in a linear array.

6. The system according to claim 1, characterized in that, The number of preset deflection angles of the inner mirror of the first scanning element is less than or equal to the number of inner reflective surfaces of the second scanning element.

7. The system according to claim 4, characterized in that, The system further includes a collimating lens disposed between the transmitting end and the first scanning element, used to convert the probe beam emitted by the transmitting end from a diverging beam into a parallel beam before emitting it to the first scanning element.

8. A variable field-of-view lidar scanning method, applied to the variable field-of-view lidar scanning system according to any one of claims 1 to 7, characterized in that, The method includes: S1, acquire the probe beam; S2, the detection beam is sent to a first scanning element fixed at a preset deflection angle, and the first scanning element reflects the detection beam in a first preset direction to obtain a reflected beam; S3, the reflected beam is reflected to the second scanning element, and the second scanning element expands the reflected beam in a second preset direction to scan the target object; S4, determine the point cloud field of view corresponding to the preset deflection angle based on the echo signal after scanning the target object; S5, adjust the preset deflection angle of the first scanning element to obtain the adjusted preset deflection angle; S6. Repeat steps S1 to S4 above to obtain the point cloud field of view corresponding to the adjusted preset deflection angle. S7 stitches together the point cloud fields of view corresponding to multiple preset deflection angles to obtain the target point cloud field of view.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method of claim 8.

10. An electronic device, characterized in that, The electronic device includes: Processor and memory; The memory stores program instructions; The processor is configured to run the program instructions to perform the method as described in claim 8.

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