A single pendulum mirror scanning structure for wind finding lidar

Abstract

The utility model provides a single pendulum mirror scanning structure for wind measuring laser radar, include: azimuth motor and pitch axis assembly, azimuth motor is hollow structure for making the laser beam of wind measuring laser radar pass through, pitch axis assembly is fixedly connected with the rotor of azimuth motor, and pitch axis assembly at least includes: pitch motor and single pendulum mirror, and single pendulum mirror is used to reflect the laser beam of passing through azimuth motor, azimuth motor is used for driving pitch axis assembly rotates around azimuth motor own axis, still be used for driving single pendulum mirror synchronous rotation through pitch axis assembly rotation to adjust the azimuth direction of reflected light beam, pitch motor is used for driving single pendulum mirror swings around preset pitch axis line to adjust the pitch direction of reflected light beam, the utility model discloses through the cooperation of azimuth motor and pitch axis assembly, drives single pendulum mirror to realize azimuth and pitch bidirectional accurate regulation, and then can drive the detection laser beam of wind measuring laser radar to realize arbitrary direction regulation.

Description

Technical Field

[0001] This utility model relates to the field of optoelectronic technology, specifically to a single-pendulum mirror scanning structure for wind-measuring lidar. Background Technology

[0002] A 3D scanning wind lidar is a coherent Doppler wind lidar that uses a scanning head to adjust the beam direction to achieve scanning at any direction and position. The coherent light generated by the laser is emitted to the telescope through a circulator. After the telescope expands and collimates the beam, the beam is deflected by a mirror in the scanner and directed in a specific direction in space. After measuring the radial wind speed information in that direction, the scanner direction is adjusted according to the scanning requirements to measure the radial wind speed at the next pointing angle. In this way, various scanning methods can be achieved, such as PPI constant elevation angle plane scanning, RHI profile scanning, DBS wind profile scanning, CAPPI volume scanning, and programmed fixed-point or trajectory scanning.

[0003] Currently, there are two types of scanners used in 3D wind measurement lidar on the market: periscope type and theodolite type (or photoelectric sphere type). Periscope type... Figures 1-2 As shown, the system consists of two rotatable planar reflectors (reflector 1 and reflector 2 in the figure). The laser beam output from the lidar body enters this scanning mechanism and is reflected by the two reflectors to adjust its direction. The first reflector (reflector 1) is called the azimuth axis reflector, and its rotation causes a change in azimuth angle. The second reflector (reflector 2) is called the elevation axis reflector, and its rotation causes a change in elevation angle. Its advantages include a large scanning range, covering 360° on the azimuth axis and -20° to 200° on the elevation axis, achieving coverage of the entire hemisphere above the radar. Its rotational inertia is moderate. Disadvantages include a large motion envelope; because the laser beam needs to pass through its hollow structure, the system's optical aperture is strongly correlated with the overall diameter of the scanning head, resulting in a large overall volume and weight, making it unsuitable for excessively large apertures; the azimuth and elevation axes are eccentric structures, requiring special structural reinforcement to prevent eccentricity; and the laser beam experiences some loss after reflection by the two reflectors.

[0004] The latitude and longitude scanning mechanism is also known as a universal scanning mechanism. When the whole thing is made into a spherical shape, it is also called a photoelectric sphere, such as... Figure 3As shown, the main body of the lidar is placed on the entire scanning mechanism. The laser beam is expanded by the telescope inside the lidar and then emitted directly. The scanning mechanism achieves pointing adjustment by driving the entire lidar to rotate. Its advantages are a large scanning range, covering 360° on the azimuth axis and -20 to 200° on the elevation axis, which can cover the entire hemisphere above the lidar. Since the entire lidar rotates, its spatial optical path is simple, without reflectors, and it is also convenient to install other active detection or passive measurement optical devices on its laser output side. The increase in optical aperture is not related to the scanning mechanism, so large-aperture telescopes (≥150mm) generally use this type of scanning mechanism. Its disadvantages are that the overall size and weight of the scanning mechanism are relatively large, and the moment of inertia is large, which leads to inflexible scanning, low speed, long settling time, long scanning time, and high peak power consumption. Utility Model Content

[0005] To address the problems of large motion envelope, size and weight limitations due to optical aperture, the need for additional reinforcement of the eccentric structure, and laser reflection loss in existing periscope-type scanning mechanisms for 3D wind measurement lidar, and the issues of large size and weight, high rotational inertia leading to low scanning efficiency and high peak power consumption in latitude and longitude scanning mechanisms, this invention proposes a single-pendulum mirror scanning structure for wind measurement lidar, comprising:

[0006] The azimuth motor has a hollow structure, which is used to allow the laser beam of the wind-measuring lidar to pass through;

[0007] The pitch axis assembly is fixedly connected to the rotor of the azimuth motor. The pitch axis assembly includes at least: a pitch motor and a pendulum mirror. The pendulum mirror is used to reflect the laser beam passing through the azimuth motor.

[0008] The azimuth motor is used to drive the pitch axis assembly to rotate around its own axis; it is also used to drive the pendulum mirror to rotate synchronously through the rotation of the pitch axis assembly, so as to adjust the azimuth direction of the reflected beam.

[0009] The pitch motor is used to drive the pendulum mirror to swing around a preset pitch axis to adjust the pitch direction of the reflected beam.

[0010] Optionally, the pitch axis assembly further includes: a reflector mount, wherein the pendulum mirror is fixedly connected to the output shaft of the pitch motor via the reflector mount;

[0011] The reflector mounting bracket is used for the pitch motor to drive the pendulum mirror.

[0012] Optionally, the pitch axis assembly further includes: a pitch axis support;

[0013] The pitch motor is fixed on the pitch axis support, and the pitch axis support is used to support the pitch motor.

[0014] Optionally, the end of the pitch axis support away from the pitch motor is fixedly connected to the rotor of the azimuth motor for a stable connection between the pitch axis assembly and the azimuth motor.

[0015] Optionally, the pitch motor includes: an encoder and a bearing;

[0016] The encoder is connected to the output shaft of the pitch motor for real-time detection of the rotation angle of the output shaft and feeding back the detected angle signal to the control unit of the wind-measuring lidar.

[0017] The bearing is sleeved on the outside of the output shaft of the pitch motor to reduce the frictional resistance when the output shaft rotates.

[0018] Optionally, the pendulum mirror is a plane mirror;

[0019] The shape of the pendulum mirror is selected from any one of ellipse, rectangle, or polygon.

[0020] Optionally, the aperture of the single pendulum mirror is not smaller than the laser beam aperture of the wind-measuring lidar.

[0021] Optionally, the reflective surface of the pendulum mirror is coated with a high-reflectivity film, and the reflection wavelength of the high-reflectivity film matches the laser beam wavelength of the wind-measuring lidar.

[0022] Optionally, the azimuth motor itself is arranged along the vertical direction, so that the pitch axis assembly rotates 360° along the horizontal plane under the drive of the azimuth motor.

[0023] Optionally, the output shaft of the pitch motor is connected to the pendulum mirror via a transmission mechanism;

[0024] The transmission mechanism is selected from any one of a reduction mechanism, a gear transmission mechanism, or a belt transmission mechanism, and is used to adjust the speed and torque output by the pitch motor to the pendulum mirror.

[0025] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0026] This invention provides a single-pendulum mirror scanning structure for wind-measuring lidar, comprising: an azimuth motor and a pitch axis assembly; the azimuth motor is a hollow structure for allowing the laser beam from the wind-measuring lidar to pass through; the pitch axis assembly is fixedly connected to the rotor of the azimuth motor, and the pitch axis assembly includes at least: a pitch motor and a single-pendulum mirror, the single-pendulum mirror being used to reflect the laser beam passing through the azimuth motor; the azimuth motor is used to drive the pitch axis assembly to rotate around its own axis; it is also used to drive the single-pendulum mirror to rotate synchronously through the rotation of the pitch axis assembly, thereby adjusting the azimuth direction of the reflected beam; the pitch motor is used to drive the single-pendulum mirror to swing around a preset pitch axis, thereby adjusting the pitch direction of the reflected beam; this invention achieves beam steering through a single pendulum mirror and a single reflecting surface, eliminating the need for a complex layout of dual reflecting mirrors, and improving efficiency. The dynamic envelope is significantly reduced, avoiding the design redundancy of needing additional reinforcement for eccentric structures. Laser reflection loss is also greatly reduced due to single reflection. Furthermore, during wind measurement, there is no need to rotate the entire radar body; only the single pendulum mirror and small pitch axis assembly are driven, resulting in a significant reduction in overall weight and moment of inertia. This not only reduces the load and peak power consumption of the drive motor but also allows for easy adaptation to compact installation scenarios such as towers and building sides. Thus, while ensuring beam pointing accuracy, the scene adaptability, operational economy, and detection reliability of the wind measurement lidar scanning mechanism are comprehensively improved. Therefore, this utility model, through the synergistic effect of the azimuth motor and the pitch axis assembly, drives the single pendulum mirror to achieve precise bidirectional adjustment of azimuth and pitch, thereby enabling arbitrary pointing adjustment of the detection laser beam of the wind measurement lidar to meet the requirements of three-dimensional wind field all-round detection. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a periscope scanner in the prior art;

[0028] Figure 2 This is a schematic diagram illustrating the reflection principle of a periscope scanner in the prior art;

[0029] Figure 3 This is a schematic diagram of the structure of a latitude and longitude ritual scanner in the prior art;

[0030] Figure 4 A schematic diagram of the component composition of a single-pendulum mirror scanning structure for wind-measuring lidar provided by this utility model;

[0031] Figure 5 This is a schematic diagram of the wind measurement process using a 3D wind-measuring lidar.

[0032] Figure 6 A schematic diagram of the single-pendulum mirror reflection principle and beam pitch direction adjustment for a single-pendulum mirror scanning structure for wind-measuring lidar provided by this utility model;

[0033] Figure 7 A schematic diagram of the overall structure of the pitch axis assembly in a single-pendulum mirror scanning structure for wind-measuring lidar provided by this utility model;

[0034] Figure 8 A schematic diagram illustrating the beam reflection principle of a single-pendulum mirror scanning structure for wind-measuring lidar provided by this utility model;

[0035] Figure 9 This invention provides a schematic diagram of the structural composition of a single-pendulum mirror scanning structure for wind-measuring lidar. Detailed Implementation

[0036] Example 1:

[0037] This invention proposes a single-pendulum mirror scanning structure for wind-measuring lidar, and the component composition diagram is shown below. Figure 4 As shown, it includes:

[0038] The azimuth motor has a hollow structure, which is used to allow the laser beam of the wind-measuring lidar to pass through;

[0039] The pitch axis assembly is fixedly connected to the rotor of the azimuth motor. The pitch axis assembly may include at least: a pitch motor and a pendulum mirror, wherein the pendulum mirror is used to reflect the laser beam passing through the azimuth motor.

[0040] The azimuth motor is used to drive the pitch axis assembly to rotate around its own axis; it is also used to drive the pendulum mirror to rotate synchronously through the rotation of the pitch axis assembly, so as to adjust the azimuth direction of the reflected beam.

[0041] The pitch motor is used to drive the pendulum mirror to swing around a preset pitch axis to adjust the pitch direction of the reflected beam.

[0042] The typical wind measurement process of a 3D wind lidar is as follows: Figure 5As shown, an initial coherent laser signal is generated from a seed source within an all-fiber laser. After being distributed by a coupler, a laser pulse meeting the detection requirements is formed under the energy support provided by the driver and the signal modulation of the modulator. Subsequently, this laser pulse is amplified through a multi-stage fiber amplifier to obtain the emitted laser that meets the requirements for wind measurement distance and intensity. The emitted laser is transmitted to the telescope via a circulator (used to separate the emitted light from the echo light to avoid mutual interference). After the telescope expands and collimates the laser beam, it is sent to a scanner, which adjusts the laser's emission direction. Finally, the laser is projected into the atmosphere and dispersed with atmospheric aerosol particles. The scattered light is reflected back along the original optical path as an echo signal. It is then transmitted again to the circulator via the scanner and telescope. The circulator guides the echo signal to the coherent detection unit. The coupler in the coherent detection unit mixes the echo signal with the local oscillation light output from the all-fiber laser. The mixed signal is sent to the balanced detector for photoelectric conversion. The resulting electrical signal is then amplified by a low-noise amplifier to reduce noise interference before being transmitted to the signal processing unit. The analog-to-digital converter in the signal processing unit converts the analog electrical signal into a digital signal. The processor then analyzes and calculates the digital signal based on the coherent Doppler principle to obtain wind field information such as wind speed and direction in the atmosphere. In existing technologies, three-dimensional wind-measuring lidar typically employs periscope-type or theodolite scanning structures to adjust the laser emission direction. The periscope-type scanning structure requires two reflectors and has an eccentric structure, resulting in a large motion envelope, size and weight easily limited by the optical aperture, and laser reflection loss. Theodolite scanning structure, on the other hand, requires rotating the entire lidar body, leading to large size and weight, high rotational inertia, low scanning efficiency, and high peak power consumption, making it unsuitable for confined installation scenarios and rapid wind field detection requirements. To address these issues, this invention considers setting up an elevation axis assembly and an azimuth motor. The azimuth motor drives the elevation axis assembly to rotate, and the elevation axis assembly drives a single pendulum mirror (also called a reflector) to swing. A schematic diagram of the reflection principle is shown below. Figure 6 As shown, the multi-directional adjustment of the single pendulum mirror is achieved through the synergistic effect of the two, thereby optimizing the performance of the scanning structure.

[0043] In one implementation, the pitch axis assembly may further include: a reflector mount, wherein the pendulum mirror can be fixedly connected to the output shaft of the pitch motor via the reflector mount;

[0044] The reflector mounting bracket is used for the pitch motor to drive the pendulum mirror.

[0045] In this implementation, the pitch axis assembly may further include: a pitch axis support;

[0046] The pitch motor is fixed on the pitch axis support, and the pitch axis support is used to support the pitch motor.

[0047] In this implementation, the end of the pitch axis support away from the pitch motor is fixedly connected to the rotor of the azimuth motor for a stable connection between the pitch axis assembly and the azimuth motor.

[0048] The overall structural diagram of the pitch axis assembly corresponding to the above implementation method is as follows: Figure 7 As shown, the pitch axis assembly uses a pitch axis support as an integrated carrier, with the pitch motor securely mounted on the support to form a basic installation unit. Simultaneously, a direct, rigid connection between the pendulum mirror and the pitch motor output shaft is achieved through a reflector mount, constructing an integrated and compact structure of the pitch axis support, pitch motor, reflector mount, and pendulum mirror. Furthermore, the end of the pitch axis support furthest from the pitch motor is directly and fixedly connected to the rotor of the azimuth motor, making the entire pitch axis assembly and azimuth motor a rigid whole without any additional connection gaps. With this integrated structural design, the power of the pitch motor can be directly transmitted to the pendulum mirror via the reflector mount, reducing energy loss and accuracy errors in intermediate transmission links. At the same time, the stable bearing of the pitch motor and the indirect positioning of the pendulum mirror by the pitch axis support ensure the coaxiality of the pitch motor output shaft and the pendulum mirror's swing axis. This structurally avoids the redundancy problem of existing periscope-type scanning mechanisms requiring additional reinforcement structures due to the eccentric arrangement of dual reflectors, thus significantly improving efficiency. This invention simplifies structural complexity and overall volume. Compared to the large rotational inertia design of traditional latitude and longitude scanning mechanisms that require the entire radar body to rotate, the pitch axis assembly of this invention integrates only a single pendulum mirror, a pitch motor, and small connecting parts. This significantly reduces the overall weight and rotational inertia, greatly reducing the load on the azimuth motor driving its rotation and the pitch motor driving the single pendulum mirror's swing. This results in more flexible scanning adjustment, faster response speed, and lower peak power consumption. Furthermore, because all components are compactly integrated on the pitch axis support, there is no need to reserve redundant movement space for dual reflectors or the radar body. The motion envelope is significantly reduced, making it easily adaptable to narrow installation scenarios such as iron towers and building sides. In addition, the direct rigid connection between the pitch axis support and the azimuth motor rotor improves the operational stability of the entire scanning structure, avoiding assembly gaps or vibration offsets caused by indirect connections of multiple components in existing structures. This ensures beam pointing accuracy and creates technical advantages such as compact structure, precise transmission, no redundancy design, and low inertia and low power consumption.

[0049] After establishing the transmission connection between the pendulum mirror and the pitch motor via a reflector mount, and ensuring the pitch motor is supported and the pitch shaft assembly is securely assembled with the azimuth motor using a pitch shaft support, thus constructing the basic mechanical transmission structure of the pitch shaft assembly, to further improve the accuracy and long-term stability of the pendulum mirror driven by the pitch motor, targeted optimization design of the functional components of the pitch motor itself can be considered. This aims to compensate for the shortcomings of the existing scanning mechanism in terms of drive accuracy control and operating resistance. Specifically:

[0050] In one implementation, the pitch motor may include: an encoder and a bearing;

[0051] The encoder is connected to the output shaft of the pitch motor for real-time detection of the rotation angle of the output shaft and feeding back the detected angle signal to the control unit of the wind-measuring lidar.

[0052] The bearing is sleeved on the outside of the output shaft of the pitch motor to reduce the frictional resistance when the output shaft rotates.

[0053] In this implementation, the encoder is connected to the output shaft of the pitch motor and provides real-time feedback of the rotation angle to the control unit. This allows the control unit to accurately capture changes in the swing angle of the pendulum mirror, promptly correct any potential angle deviations, and prevent beam pointing deviations caused by inaccurate angle control. This improves the accuracy of the pendulum mirror's pitch adjustment, thereby ensuring the accuracy of the wind-measuring lidar in detecting wind fields in specific airspaces. It also overcomes the adjustment error problem that easily occurs in existing scanning mechanisms due to the lack of real-time angle feedback. Simultaneously, the bearing sleeve on the outside of the output shaft effectively reduces frictional resistance during rotation, minimizing mechanical wear during output shaft operation. This makes the pendulum mirror swing more smoothly and without jamming when driven by the pitch motor, reducing motor noise and energy consumption, and extending the service life of the pitch motor and output shaft. Therefore, this implementation, through the synergistic effect of the encoder's precise feedback and the bearing's low-resistance support, enables the entire pitch adjustment system to maintain high-precision pointing while possessing more stable long-term operating capabilities.

[0054] After achieving real-time detection and feedback of the pitch motor output shaft rotation angle through an encoder, reducing the rotational friction resistance of the output shaft with the help of bearings, and optimizing the driving accuracy and smooth operation of the pitch motor, the optical characteristics and structural adaptability of the single pendulum mirror, as the core component of laser beam reflection in the entire scanning structure, directly determine the laser reflection efficiency and beam pointing stability. Therefore, it is necessary to further clarify the specific design scheme of the single pendulum mirror to ensure that the laser beam can complete the reflection adjustment efficiently and stably. Specifically:

[0055] In one implementation, the single pendulum mirror can be a plane mirror; the single pendulum mirror adopts a plane mirror design, which can ensure that the incident laser beam propagates in accordance with a fixed reflection law and avoid beam divergence or direction shift caused by non-plane mirrors.

[0056] The shape of the pendulum mirror is selected from any one of ellipse, rectangle or polygon;

[0057] In this implementation, the aperture of the single pendulum mirror is not smaller than the laser beam aperture of the wind-measuring lidar.

[0058] In this implementation, the reflective surface of the single pendulum mirror is coated with a high-reflectivity film, and the reflection wavelength of the high-reflectivity film matches the laser beam wavelength of the wind-measuring lidar.

[0059] In this implementation, the schematic diagram of the beam reflection principle of the single pendulum mirror scanning structure is as follows: Figure 8 As shown, the angular relationship between the incident laser beam, the pendulum mirror, and the reflected laser beam is clearly illustrated. Here, α represents the angle between the incident laser beam and the initial normal of the pendulum mirror's reflecting surface (i.e., the incident angle), θ represents the swing angle of the pendulum mirror around the preset pitch axis (i.e., the angle by which the pendulum mirror deflects from its initial position towards the target direction), and φ represents the final deflection angle of the reflected laser beam relative to the initial reference direction of the incident laser beam after reflection by the pendulum mirror (i.e., the actual pitch pointing angle of the reflected beam). According to the law of reflection, when the pitch motor drives the pendulum mirror to swing around the preset pitch axis by an angle θ, the normal of the pendulum mirror's reflecting surface deflects synchronously by an angle θ. The angle between the incident beam and the normal of the deflected reflecting surface... The angle changes to α±θ (depending on the swing direction), thus establishing a fixed relationship between the deflection angle φ of the reflected beam and the swing angle θ of the single pendulum mirror (usually satisfying φ=2θ, but specifically needs to be combined with the initial setting of the incident angle α). This angular correspondence allows the control unit to precisely adjust the pitch pointing angle φ of the reflected beam by precisely controlling the rotation angle of the output shaft of the pitch motor (i.e., the swing angle θ of the single pendulum mirror). This provides clear principle support for wind-measuring lidar to project the laser beam to the target airspace as needed and obtain wind field information at a specific pitch angle. It also intuitively demonstrates the simplicity and controllability of the single pendulum mirror single reflective surface design in terms of beam pointing adjustment logic.

[0060] In the above implementation, the single pendulum mirror adopts a planar reflector design, which ensures that the incident laser beam propagates according to a fixed reflection law, avoiding beam divergence or direction deviation caused by non-planar mirrors. The choice of elliptical, rectangular, or polygonal shapes can flexibly adapt to the internal installation space and surrounding component layout of different wind-measuring lidars, breaking the limitation of single shape on equipment compatibility and improving the scene adaptability of the scanning structure. At the same time, the design of the single pendulum mirror's light-transmitting aperture being no smaller than the laser beam aperture can completely cover the incident laser beam cross section, avoiding beam incompleteness and energy loss caused by edge obstruction, and ensuring that the laser beam is completely projected into the atmosphere. The reflective surface is coated with a high-reflectivity film that matches the wavelength of the laser beam, which can significantly reduce the energy attenuation of the reflection link, thereby extending the effective detection range of the radar and enhancing the echo signal strength.

[0061] After determining that the pendulum mirror is a plane reflector, clarifying its shape selection range, aperture adaptation requirements, and high-reflectivity film wavelength matching design, and ensuring that the laser beam has efficient reflection conditions, in order to meet the requirements of wind-measuring lidar for full-airspace wind field detection, and to adapt to the differentiated requirements for scanning speed and torque in different scenarios, it is possible to consider optimizing the overall mechanism's motion range and power transmission method to expand the functional coverage and scenario adaptability of the scanning structure. Specifically:

[0062] In one implementation, the azimuth motor's own axis can be arranged vertically, allowing the pitch axis assembly to rotate 360° along the horizontal plane under the drive of the azimuth motor. In this implementation, the vertical arrangement of the azimuth motor's own axis drives the pitch axis assembly to rotate the single pendulum mirror 360° without dead angles along the horizontal plane, covering all horizontal airspace. This meets the requirements of wind-measuring lidar for omnidirectional wind field detection without requiring additional adjustment of the motor's installation angle. It effectively avoids the azimuth detection dead angle problem caused by unreasonable axis arrangement in existing scanning mechanisms, providing stable directional drive support for detection modes requiring large-area horizontal coverage, such as PPI fixed-pitch-angle plane scanning. Furthermore, the vertical axis arrangement of the azimuth motor not only ensures the smoothness of horizontal rotation but also reduces eccentric torque during rotation, lowering wear on the mechanism.

[0063] In one implementation, the output shaft of the pitch motor can be connected to the pendulum mirror via a transmission mechanism;

[0064] The transmission mechanism can be selected from any one of a reduction mechanism, a gear transmission mechanism, or a belt transmission mechanism, and is used to adjust the speed and torque output by the pitch motor to the pendulum mirror;

[0065] In this implementation, the output shaft of the pitch motor is connected to the pendulum mirror via a reduction mechanism, gear transmission mechanism, or belt transmission mechanism. The transmission type can be flexibly selected according to the actual detection requirements. For example, the reduction mechanism can reduce the speed and increase the torque, which is suitable for scenarios where the pendulum mirror needs to swing slowly and accurately (such as fine detection of a specific height layer in RHI profile scanning). The gear transmission mechanism can ensure high rigidity and high precision of power transmission, meeting the scanning requirements for rapid response. The belt transmission mechanism has buffering and shock absorption characteristics, which is suitable for scenarios with high requirements for operational stability. This diversified transmission selection can improve the compatibility of the scanning structure with different models of wind measurement lidar, so that the pitch adjustment of the pendulum mirror can accurately match the speed and torque requirements of different scanning modes.

[0066] In summary, this invention addresses the technical problems of existing periscope-type scanning mechanisms for 3D wind measurement lidar, such as large motion envelope, size and weight limitations due to optical aperture, the need for additional reinforcement of the eccentric structure, and laser reflection loss. It also addresses the problems of the theodolite-type scanning mechanisms, such as large size and weight, large moment of inertia leading to low scanning efficiency and high peak power consumption. Therefore, this invention proposes a single-pendulum mirror scanning structure for wind measurement lidar. A schematic diagram of the overall structure is shown below. Figure 9 As shown, the laser, as the core component of laser emission, provides a laser signal conforming to the coherent Doppler principle for the wind measurement process. The telescope is connected to the laser's optical path and is used to expand and collimate the laser output from the laser, ensuring that the laser has a stable propagation direction and detection intensity. The azimuth motor consists of a motor rotor and a motor stator. The motor stator provides fixed support to ensure the overall stability of the mechanism, and the motor rotor can rotate around its own axis and is directly fixed to the pitch axis assembly, forming the horizontal drive foundation. The pitch motor is integrated into the pitch axis assembly and serves as the power source for the pitch motion of the pendulum mirror, directly driving the pendulum mirror to swing around a preset axis. The pendulum mirror, as the core component of beam reflection, receives the laser beam after it has been expanded and collimated by the telescope and passes through the hollow structure of the azimuth motor. It adjusts the laser beam pointing by adjusting its own azimuth and pitch attitude. The main controller, as the control center, establishes signal connections with the laser, azimuth motor, and pitch motor respectively, and is used to output control commands to regulate the operating status of each component, ultimately forming a complete working link of laser emission, beam expansion, attitude adjustment, and pointing control. Therefore, through the synergistic design of the above-mentioned structures, this utility model replaces the periscope-style double reflector with a single pendulum mirror and single reflector, eliminating the redundant space and eccentric reinforcement structure of the double mirror layout. At the same time, it only drives small components such as the single pendulum mirror and the pitch motor, without having to support the entire radar body like the latitude and longitude mechanism, thus significantly reducing the overall size and weight and shrinking the motion envelope. The azimuth motor achieves 360° rotation in the horizontal plane without dead angles through the rigid connection between the motor rotor and the pitch shaft assembly. Combined with the precise drive of the single pendulum mirror by the pitch motor and the real-time control of the main controller, it can significantly reduce the moment of inertia, improve the scanning response speed and pointing accuracy, and comprehensively improve the scene adaptability, detection efficiency and operating economy of the wind-measuring lidar, providing reliable scanning structure support for all-round, high-precision detection of three-dimensional wind fields.

[0067] Those skilled in the art will understand that embodiments of this invention can be provided as methods, systems, or computer program products. Therefore, this invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0068] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0069] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0070] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit its protection scope. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this utility model, they can still make various changes, modifications or equivalent substitutions to the specific implementation of the application, but these changes, modifications or equivalent substitutions are all within the protection scope of the claims pending approval.

Claims

1. A single-pendulum mirror scanning structure for wind-measuring lidar, characterized in that, include: Azimuth motor and pitch axis assembly; The azimuth motor has a hollow structure, which is used to allow the laser beam of the wind-measuring lidar to pass through; The pitch axis assembly is fixedly connected to the rotor of the azimuth motor. The pitch axis assembly includes at least: a pitch motor and a pendulum mirror. The pendulum mirror is used to reflect the laser beam passing through the azimuth motor. The azimuth motor is used to drive the pitch axis assembly to rotate around its own axis; it is also used to drive the pendulum mirror to rotate synchronously through the rotation of the pitch axis assembly, so as to adjust the azimuth direction of the reflected beam. The pitch motor is used to drive the pendulum mirror to swing around a preset pitch axis to adjust the pitch direction of the reflected beam.

2. The scanning structure as described in claim 1, characterized in that, The pitch axis assembly further includes: a reflector mounting base, wherein the pendulum mirror is fixedly connected to the output shaft of the pitch motor via the reflector mounting base; The reflector mounting bracket is used for the pitch motor to drive the pendulum mirror.

3. The scanning structure as described in claim 1, characterized in that, The pitch axis assembly also includes: a pitch axis support; The pitch motor is fixed on the pitch axis support, and the pitch axis support is used to support the pitch motor.

4. The scanning structure as described in claim 3, characterized in that, The end of the pitch axis support away from the pitch motor is fixedly connected to the rotor of the azimuth motor, which is used for a stable connection between the pitch axis assembly and the azimuth motor.

5. The scanning structure as described in claim 1, characterized in that, The pitch motor includes: an encoder and a bearing; The encoder is connected to the output shaft of the pitch motor for real-time detection of the rotation angle of the output shaft and feeding back the detected angle signal to the control unit of the wind-measuring lidar. The bearing is sleeved on the outside of the output shaft of the pitch motor to reduce the frictional resistance when the output shaft rotates.

6. The scanning structure as described in claim 1, characterized in that, The pendulum mirror is a plane reflecting mirror; The shape of the pendulum mirror is selected from any one of ellipse, rectangle, or polygon.

7. The scanning structure as described in claim 6, characterized in that, The aperture of the single pendulum mirror is not less than the laser beam aperture of the wind-measuring lidar.

8. The scanning structure according to any one of claims 1-7, characterized in that, The reflective surface of the pendulum mirror is coated with a high-reflectivity film, and the reflection wavelength of the high-reflectivity film matches the laser beam wavelength of the wind-measuring lidar.

9. The scanning structure as described in claim 1, characterized in that, The azimuth motor's own axis is arranged in a vertical direction, so that the pitch axis assembly rotates 360° along the horizontal plane under the drive of the azimuth motor.

10. The scanning structure as described in claim 1, characterized in that, The output shaft of the pitch motor is connected to the pendulum mirror via a transmission mechanism; The transmission mechanism is selected from any one of a reduction mechanism, a gear transmission mechanism, or a belt transmission mechanism, and is used to adjust the speed and torque output by the pitch motor to the pendulum mirror.

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