Double-axis scanning type laser radar device

Abstract

The invention provides a double-axis scanning type laser radar device, and relates to the technical field of laser radars. The laser radar device comprises a laser emitting unit, a reflecting unit, a receiving unit and a data processing unit, the laser emitting unit is used for generating and emitting a laser beam; the reflection unit is used for realizing independent deflection of the laser beam in the horizontal and vertical directions; and the receiving unit is used for receiving the echo signal and the reference signal which are reflected by the target object, performing coherent superposition on the reference signal and the echo signal and then transmitting the reference signal and the echo signal to the data processing unit for demodulation and analysis, thereby extracting the distance, shape and motion information of the target object. The laser radar device has the advantages of being high in scanning precision, wide in detection range, high in environmental adaptability and the like, and can keep high measurement precision and data processing efficiency under various complex environmental conditions.

Description

Technical Field

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

[0002] As industrial measurement places greater demands on the size and shape of workpieces, LiDAR, as a sensing device that can obtain high-resolution three-dimensional spatial information, has gradually become a core component in various applications. Traditional LiDARs mostly use single-axis rotation or fixed field of view scanning mode. This design has problems such as limited field of view, low scanning efficiency, and insufficient measurement accuracy when detecting target objects. At the same time, in order to solve complex scene recognition in multi-target environments, existing LiDARs often face challenges such as complex signal processing and reduced scanning accuracy when improving detection resolution and increasing detection distance. Therefore, how to improve scanning speed and accuracy while ensuring high-resolution detection has become a difficult problem that needs to be solved in LiDAR design.

[0003] The single-axis rotation scanning mode adopted by traditional LiDAR scans the light beam in a single direction, which limits the detection range and is prone to scanning blind spots or reduced resolution in complex target environments. In order to achieve full-field three-dimensional detection, current multi-beam LiDARs usually use multiple laser sources and receiving units, but this not only increases the complexity of the system, but also leads to increased costs, and the signal demodulation process is complex and susceptible to interference from environmental noise. In addition, traditional LiDAR systems are prone to reduced measurement accuracy in environments where the movement of objects changes greatly. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a dual-axis scanning laser radar device in response to the above-mentioned deficiencies in the prior art, so as to solve the technical problems of traditional laser radar in target object identification and measurement in complex environments, such as insufficient accuracy, limited detection range, low scanning efficiency and poor environmental adaptability.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: a dual-axis scanning laser radar device, including a laser emitting unit, a reflecting unit, a receiving unit and a data processing unit; the laser emitting unit is used to generate and emit a laser beam; the reflecting unit is used to realize independent deflection of the laser beam in the horizontal and vertical directions; the receiving unit is used to receive the echo signal and the reference signal reflected back by the target object, and coherently superimpose the reference signal and the echo signal and transmit them to the data processing unit for demodulation and analysis, so as to extract the distance, shape and motion information of the target object.

[0006] Preferably, the laser emitting unit comprises a laser light source, a beam splitter, a collimator and a zoom lens; the laser source is used to generate a stable continuous laser signal, and the laser light beam is divided into a signal light and a reference light by the beam splitter; after the signal light is collimated into a parallel light beam by the collimator, the focal length and diameter of the light beam are adjusted by the zoom lens, so as to control the divergence angle and focus point position of the laser light beam according to the distance condition of the target object; the reference light is used as the local oscillator light in the subsequent signal demodulation process.

[0007] Preferably, the reflection unit includes two independently arranged wedge-shaped reflectors, which are respectively used to realize independent deflection of the laser beam in the horizontal and vertical directions; the two wedge-shaped reflectors are respectively driven to rotate by a horizontal motor and a vertical motor, so as to control the deflection of the laser beam in the horizontal and vertical directions, forming a dual-axis scanning mode; the scanning angle and scanning speed of the two wedge-shaped reflectors are dynamically adjusted according to a preset path; the wedge-shaped reflector in the horizontal direction can realize omnidirectional scanning from 0 to 360 degrees, and the wedge-shaped reflector in the vertical direction can realize precise adjustment of ±15 degrees.

[0008] Preferably, the receiving unit includes a beam expander, a mixer and a photodetector; the beam expander contains a meniscus lens, which is arranged on the optical path of the echo signal reflected by the target object, and is used to receive the reflected echo signal on the optical path of the echo signal and amplify the receiving diameter of the reflected light beam of the target object, so as to increase the effective aperture of the receiving light beam, thereby improving the receiving efficiency of the echo signal and the signal-to-noise ratio of the mixing signal; the mixer is arranged at the intersection of the reference light and the echo signal beam, and under the protection of the selection protection shell, the local oscillator light and the echo signal are simultaneously received through the nonlinear element and the local oscillator, and the reference light and the echo signal are coherently superimposed through the coherent demodulation technology in the frequency selection loop, so as to obtain the distance, speed and direction information of the target object; the photodetector is used to convert the coherently demodulated optical signal into an electrical signal, and transmit it to the data processing unit.

[0009] Preferably, the data processing unit performs signal demodulation based on the signal received by the mixer, and includes a signal filtering module, a data classification module and a three-dimensional imaging module; the signal filtering module is used to remove background noise and interference signals in the electrical signal transmitted by the receiving unit, and extract effective target signals according to preset threshold conditions; the data classification module analyzes and identifies the distance information of multiple target objects based on the received echo signal intensity and phase information of the target objects; the three-dimensional imaging module generates high-precision three-dimensional point cloud data based on the distance and angle information of the target objects, and can perform dynamic tracking and trajectory prediction according to the movement characteristics of the target objects.

[0010] Preferably, the laser radar device also includes a control module, which is used to dynamically adjust the rotation speed and angle of the wedge-shaped reflector in the horizontal and vertical directions according to a predetermined scanning path and environmental information of the target area; the control module can pre-set the scanning path and automatically adjust the scanning speed and angle according to real-time environmental information, thereby ensuring that the laser radar can flexibly respond to complex and changeable detection scenes.

[0011] Preferably, the laser radar device also includes a wireless communication module, which is connected to the data processing unit and is used to transmit the processed target object data to an external device to achieve remote monitoring and data analysis.

[0012] Preferably, the laser radar device further comprises an extended function module, the extended function module comprises a plurality of laser processing units; the laser emitted by the laser emitting unit passes through the laser processing units before reaching the reflecting unit; the laser processing unit comprises a beam expander, a light guide column, a focusing mirror and a beam shaper connected in sequence;

[0013] The beam expander is used to expand the diameter of the laser beam and increase the effective detection area; the light guide plays a role in guiding and transmitting light in the optical path to ensure that the optical signal can propagate along a predetermined path; the focusing mirror allows the light emitted by the laser emitting unit to be smoothly and continuously converged to one point; the beam shaper forms a multi-channel laser beam detection mode to improve the detection speed and resolution. Preferably, the laser radar device also includes a housing, and the laser emitting unit, the reflection unit, the receiving unit and the data processing unit are positioned and fixed inside the housing by a clamp and a nut, and the housing is tightly combined with the laser emitting unit, the reflection unit, the receiving unit and the data processing unit by a snap-on connection.

[0014] Preferably, the laser radar device also includes a GNSS module and an IMU module connected to the control module to achieve precise measurement.

[0015] The beneficial effects of adopting the above technical solution are: a dual-axis scanning laser radar device provided by the present invention can achieve:

[0016] (1) Large-range high-resolution scanning: The present invention realizes independent adjustment of the laser beam in the horizontal and vertical directions through the dual-axis scanning design of the double wedge reflector, effectively improving the scanning range and angular resolution of the laser radar, and can complete large-range high-precision three-dimensional detection in a shorter scanning time.

[0017] (2) High-precision signal demodulation: By adopting mixing demodulation technology and beam expansion design, the signal-to-noise ratio of the received echo signal is significantly improved, which can achieve high-precision target recognition and measurement in complex environments and effectively reduce the impact of environmental noise on the signal demodulation process.

[0018] (3) Multi-target recognition and dynamic tracking: The data processing unit can realize real-time recognition and dynamic tracking of multiple target objects based on the echo signals and motion characteristics of the target objects, which is particularly suitable for workpiece detection scenarios in complex environments.

[0019] (4) Compact structure and wide application: The present invention adopts a highly integrated design with a compact overall structure and is easy to install. It can be widely used in various application scenarios such as industrial measurement and precision mapping.

[0020] In summary, the present invention provides a high-resolution laser radar device based on a dual-axis scanning design, which has the advantages of high scanning accuracy, wide detection range, and strong environmental adaptability, and can maintain high measurement accuracy and data processing efficiency under a variety of complex environmental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic structural diagram of a dual-axis scanning laser radar device provided by an embodiment of the present invention;

[0022] Figure 2 A schematic diagram of the internal structure of a dual-axis scanning laser radar device after disassembly provided by an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of two independently arranged wedge-shaped reflectors provided in an embodiment of the present invention;

[0024] Figure 4 A schematic diagram of the structure of a receiving unit provided in an embodiment of the present invention;

[0025] Figure 5 A schematic diagram of the extended function module structure provided in an embodiment of the present invention.

[0026] In the figure: 1. laser emitting unit; 2. reflecting unit; 3. receiving unit; 4. data processing unit; 5. extended function module; 11. laser light source; 12. beam splitter; 13. collimator; 14. zoom lens; 21. wedge-shaped reflector; 22. horizontal motor and vertical motor; 211. first wedge-shaped reflector; 212. second wedge-shaped reflector; 31. beam expander; 32. mixer; 33. photodetector; 311. meniscus lens; 321. nonlinear element; 322. local oscillator; 324. protective shell; 323. frequency selection circuit; 41. signal filtering module; 42. data classification module; 43. three-dimensional imaging module; 51. laser processing unit; 511. beam expander; 512. light guide column; 513 focusing mirror; 514. beam shaper; 61. clamp; 62. nut; 63. shell. DETAILED DESCRIPTION

[0027] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0028] In this embodiment, a dual-axis scanning laser radar device, such as Figure 1 , 2 As shown, it includes a laser emitting unit 1, a reflecting unit 2, a receiving unit 3, a data processing unit 4 and a wireless communication module; the laser emitting unit 1 is used to generate and emit a laser beam; the reflecting unit 2 is used to realize the independent deflection of the laser beam in the horizontal and vertical directions; the receiving unit 3 is used to receive the echo signal and the reference signal reflected back by the target object, and transmit the reference signal and the echo signal to the data processing unit 4 for demodulation and analysis after coherent superposition, so as to extract the distance, shape and motion information of the target object. The wireless communication module is connected to the data processing unit 4, and is used to transmit the processed target object data to an external device to realize remote monitoring and data analysis. The wireless communication module enables the laser radar device to communicate with an external control system or monitoring platform in real time, and transmits the detected target object data to the remote device in a high-speed and stable manner, so as to realize remote monitoring and real-time decision support for the target. This module is particularly suitable for industrial optical detection and optical ranging systems.

[0029] In this embodiment, the laser emitting unit 1 includes a laser light source 11, a beam splitter 12, a collimator 13 and a zoom lens 14; the laser source 11 is used to generate a stable continuous laser signal, and the laser beam is divided into a signal light and a reference light through the beam splitter 12; after the signal light is collimated into a parallel light beam by the collimator 13, the focal length and diameter of the light beam are adjusted by the zoom lens 14, so as to flexibly control the divergence angle and the focus position of the laser beam according to the distance condition of the target object; the reference light is used as the local oscillator light in the subsequent signal demodulation process. The design of the laser emitting unit 1 can provide a stable laser beam. The design of the beam splitter 12 can effectively divide the light beam into a signal light for detection and a reference light for the subsequent demodulation process, so as to ensure that the distance and speed information of the target object can be accurately interpreted. The collimator 13 ensures that the laser beam maintains sufficient collimation within different distance ranges by adjusting the divergence angle of the light beam, thereby improving the detection accuracy.

[0030] The zoom lens 14 is arranged in the signal light path, and is used to dynamically adjust the emission diameter and focal length of the signal light beam according to the distance of the target object. The zoom lens 14 can flexibly adjust the focus and spot diameter of the laser beam to adapt to different target objects at different distances. For long-distance targets, the lens will be adjusted to a smaller divergence angle to achieve more accurate detection, while for short-distance targets, the lens will expand the beam diameter to cover a wider range. In this way, the device can achieve rapid switching and measurement of long and short targets according to actual detection needs.

[0031] In this embodiment, the laser light source 11 is used to generate a continuous laser beam with a central wavelength of 1550nm, and the laser beam is divided into two parts, signal light and reference light, by a beam splitter 12. Among them, the signal light is used for spatial detection of the target object, and the reference light is used as a local oscillator signal for subsequent mixing demodulation. In this embodiment, the zoom lens 14 is a liquid zoom lens, and its lens focal length can be quickly adjusted by voltage drive, so that precise focusing can be achieved at different target distances during the scanning process. The focal length range of the zoom lens 14 can be continuously adjusted between 50mm and 300mm, so as to adapt to the detection requirements from short distance (within 1 meter) to long distance (tens of meters or even hundreds of meters).

[0032] The reflecting unit 2 includes: Figure 3 The two independently arranged wedge-shaped reflectors 21 shown are used to realize the independent deflection of the laser beam in the horizontal and vertical directions respectively; the two wedge-shaped reflectors are respectively driven by the horizontal motor and the vertical motor 22 to rotate, thereby controlling the horizontal and vertical deflection of the laser beam to form a dual-axis scanning mode; the scanning angle and scanning speed of the two wedge-shaped reflectors are dynamically adjusted according to the preset path, thereby realizing a wide range of high-resolution scanning; the wedge-shaped reflector in the horizontal direction can realize omnidirectional scanning from 0 to 360 degrees, and the wedge-shaped reflector in the vertical direction can realize accurate adjustment of ±15 degrees, and the detection coverage and angular resolution of the laser radar are effectively improved through the dual-axis scanning mode. The two wedge-shaped reflectors 21 in the reflection unit 2 realize independent control of the laser beam in two directions, so that the beam can be flexibly adjusted to cover the target area without moving the entire device.

[0033] In this embodiment, after the laser beam passes through the first wedge-shaped reflector 211, the horizontal direction of the signal beam is adjusted to a predetermined angle; then, through the second wedge-shaped reflector 212, the vertical angle is further adjusted. Through the combined control of the two reflectors, the laser beam can be flexibly scanned in a large range in both the horizontal and vertical directions, thereby covering the entire detection area. Compared with the traditional single-axis rotation scanning mode, the dual-axis reflector design of the present invention can effectively improve the scanning speed and angular resolution by independently controlling the beam deflection in the horizontal and vertical directions, and can accurately adjust the detection path of the beam to adapt to different target areas and application scenarios. In some cases, the rotation speed of the horizontal and vertical axes can be dynamically adjusted according to the target distance and movement speed to ensure efficient detection capabilities in complex environments.

[0034] In the present invention, the wedge-shaped reflector 21 is used to adjust the propagation path of the laser beam, control the scanning angle or optimize the performance of the optical system. The application of the wedge-shaped reflector in the laser radar is intended to improve beam control, reduce beam deformation and improve scanning accuracy. Two-axis scanning laser radars usually use two types of rotational motion. Horizontal axis rotation: The beam rotates around the horizontal axis to achieve a 360° horizontal scan of the surrounding environment. Vertical axis rotation: The beam rotates around the vertical axis to achieve up and down scanning of the environment. In order to achieve these scans, the laser radar system needs to accurately control the emission direction of the laser beam to ensure that the radar can cover a wide environmental area and collect high-quality three-dimensional point cloud data. In this process, the wedge-shaped reflector is often used to adjust the direction of the laser beam, especially in the scanning system, the wedge-shaped reflector can accurately control the deflection angle of the laser beam through its special geometric shape. This can help the radar system scan in different directions while reducing deviations and distortions in beam transmission. The wedge-shaped reflector is used in this laser radar device to accurately adjust the path of the laser beam in horizontal scanning. By adjusting the angle of the wedge-shaped reflector, the scanning angle of the laser beam can be controlled, so that the radar can cover a wider area. Similarly, wedge-shaped reflectors can also be used to optimize vertical scanning to ensure the stability and accuracy of laser beam propagation in the vertical direction. Especially at small vertical scanning angles, wedge-shaped reflectors can effectively avoid excessive scattering or distortion of laser beams. In some high-precision LiDAR systems, wedge-shaped reflectors can also be used to adjust the shape and size of the beam. When the laser beam passes through the wedge-shaped reflector, it will undergo a certain deformation, which can be designed as needed to help the radar system obtain specific beam characteristics when scanning. In some application scenarios, it may be necessary to expand or compress the diameter of the laser beam to adapt to a specific scanning range. The wedge-shaped reflector can adjust the propagation path of the beam by changing its thickness or angle, thereby achieving a predetermined beam adjustment. The design of the wedge-shaped reflector can also effectively reduce the scattering effect of the beam during the scanning process, ensuring that the LiDAR can maintain a high beam focus and transmission efficiency when scanning a large range of environments. The arrangement of optical components and the design of the optical path are very important in this LiDAR system. The wedge-shaped reflector can effectively reduce or eliminate the optical distortion caused by changes in the scanning angle. For example, when a laser beam passes through multiple optical elements, a wedge reflector can be used to adjust the optical path differences between different optical elements, thereby reducing distortion and ensuring the stability of the laser beam. The wedge reflector can change the propagation direction of the incident light through the special design of its wedge-shaped surface. In a dual-axis scanning LiDAR system, a wedge reflector is often used to precisely deflect the laser beam to a predetermined scanning angle. This function is critical to the accuracy and coverage of the scanning system, especially in application scenarios that require high-precision ranging and imaging. The direct role of the wedge reflector in this LiDAR is to precisely control the light beam through the wedge reflector, so that the LiDAR can scan the environment more accurately and improve the accuracy of the measurement.Wedge-shaped reflectors can also effectively reduce errors or distortions caused by angle changes or unstable beam shapes during scanning, ensuring the quality of point cloud data. The design of wedge-shaped reflectors can be flexibly adjusted according to different application requirements, such as changing the scanning angle, beam shape or size, thereby improving the adaptability and flexibility of the lidar. The role of wedge-shaped reflectors in dual-axis scanning lidar is indispensable. It not only helps to accurately adjust the propagation path of the laser beam, but also optimizes scanning accuracy, reduces optical distortion, and improves the overall performance of the radar system.

[0035] The receiving unit 3 is as follows Figure 4 As shown, it includes a beam expander 31, a mixer 32 and a photodetector 33; the beam expander 31 contains a meniscus lens 311, which is arranged on the optical path of the echo signal reflected by the target object, and is used to amplify the receiving diameter of the reflected light beam of the target object on the optical path of the reflected echo signal, so as to improve the effective aperture of the received light beam, thereby improving the receiving efficiency of the echo signal and the signal-to-noise ratio of the mixing signal, and increasing the receiving efficiency of the echo signal; the mixer 32 is arranged at the intersection of the reference light and the echo signal beam, and receives the intrinsic light and the echo signal at the same time through the nonlinear element 321 and the local oscillator 322 under the protection of the selection protection shell 324, and coherently superimposes the reference light and the echo signal in the frequency selection loop 323 through the coherent demodulation technology, and accumulates and superimposes the return signals of multiple laser pulses by using the coherent accumulation technology. Through the superposition processing, the intensity of the target signal can be enhanced and the signal-to-noise ratio can be improved. In this way, even if the target signal is very weak, a signal of sufficient strength can be obtained through coherent accumulation technology, thereby improving the ranging accuracy of the radar system and obtaining the distance, speed and direction information of the target object; the photodetector 33 is used to convert the coherently demodulated optical signal into an electrical signal and transmit it to the data processing unit for further processing.

[0036] The design of the beam expander 31 can expand the diameter of the echo signal beam to a sufficiently large range to ensure that the receiving unit can efficiently capture the reflected light signal and maintain a high signal-to-noise ratio in the case of weak signals. In this way, the receiving unit 3 can more accurately detect and identify the echo signal of the target object, thereby improving the overall detection performance of the laser radar system.

[0037] Through mixing and demodulation, the device can accurately extract motion parameters in the case of high-speed moving targets and output the real-time position information of the target in a timely manner. This design is particularly suitable for high-precision target tracking in dynamic scenes such as autonomous driving and robot navigation.

[0038] In this embodiment, the beam expander 31 is designed as an aspherical lens made of birefringent material, which can effectively reduce the optical distortion in the receiving optical path, and effectively improve the mixing efficiency through the large aperture receiving design after beam expansion. The mixer 32 is based on the principle of optical coherent detection, and performs coherent demodulation of the signal through the phase difference between the local oscillator signal and the echo signal. The demodulated optical signal is converted into an electrical signal through a photodetector and transmitted to the data processing unit for analysis.

[0039] The data processing unit 4 performs signal demodulation based on the signal received by the mixer 32, and includes a signal filtering module 41, a data classification module 42 and a three-dimensional imaging module 43; the signal filtering module 41 is used to remove background noise and interference signals in the electrical signal transmitted by the receiving unit, and extract valid target signals according to preset threshold conditions, to ensure that the data processing unit 4 only processes valid target signals, thereby improving the accuracy of target detection; the data classification module 42 analyzes and identifies the distance information of multiple target objects based on the received echo signal intensity and phase information of the target object; the three-dimensional imaging module 43 generates high-precision three-dimensional point cloud data based on the distance and angle information of the target object, and can perform dynamic tracking and trajectory prediction according to the movement characteristics of the target object.

[0040] In this embodiment, during the three-dimensional imaging process, the three-dimensional imaging module can convert the demodulated signal data into three-dimensional point cloud data of the target object, and filter and optimize the point cloud data through a high-precision algorithm. Finally, the data processing unit 4 can generate a three-dimensional image of the target object and output the motion trajectory and speed information of the target.

[0041] The laser radar device also includes a control module (DSP digital signal processor), which is used to dynamically adjust the rotation speed and angle of the wedge-shaped reflector in the horizontal and vertical directions according to the predetermined scanning path and the characteristics of the target area; the control module can pre-set the scanning path and automatically adjust the scanning speed and angle according to real-time environmental information, thereby ensuring that the laser radar can flexibly respond to complex and changeable detection scenarios. For example, in industrial measurement, the control module can adjust the scanning angle and range according to the size of the workpiece, the surface roughness and the distribution of surrounding objects to obtain the best detection effect.

[0042] In this embodiment, the laser radar device also includes: Figure 5 The extended function module 5 shown in the figure comprises a plurality of laser processing units 51; the laser emitted by the laser emitting unit is processed by these units before reaching the reflecting unit; the laser processing unit comprises a beam expander 511, a light guide column 512, a focusing mirror 513 and a beam shaper 514 connected in sequence;

[0043] The beam expander 511 is used to expand the diameter of the laser beam and increase the effective detection area without losing too much energy. Although the specific working principle of the light guide column 512 may vary depending on the design of different laser radars, it usually guides and transmits light in the optical path to ensure that the optical signal can propagate along the predetermined path; the focusing mirror 513 allows the light emitted by the laser emitting unit to be smoothly and continuously converged to one point, with good light spot convergence effect and less light energy loss; the beam shaper 514 forms a multi-channel laser beam detection mode, thereby significantly improving the detection speed and resolution. These components share data and work together with other modules in the laser radar system through switches or routers, etc., to achieve real-time, high-precision ranging.

[0044] In this embodiment, the laser radar device also includes a shell 63, and the laser emitting unit, the reflecting unit, the receiving unit and the data processing unit are positioned and fixed inside the shell by a clamp 61 and a nut 62. The shell is tightly combined with the laser emitting unit, the reflecting unit, the receiving unit and the data processing unit through a snap-on connection.

[0045] The key units in the laser radar device, namely the laser emitting unit 1, the reflecting unit 2, the receiving unit 3 and the data processing unit 4, are firmly connected into a whole through a series of precise components; specifically, these units are first preliminarily positioned and fixed by the clamp 61; the design of the clamp 61 not only ensures the accurate relative position between the units, but also provides preliminary mechanical support. Subsequently, the nut 62 is used to further tighten these units. The nut 62 cooperates with the clamp 61 to firmly lock the units together through a threaded connection to prevent loosening under vibration or impact conditions. This connection method not only provides additional stability, but also ensures the reliability of the laser radar device in long-term use. The housing 63 serves as the outer protective layer of the entire laser radar device, and is tightly combined with the internal components through a snap-on connection. The housing 63 not only provides protection for the internal units to prevent interference and damage from the external environment, but also enhances the stability and durability of the entire device through its sturdy structure. In summary, the clamp 61, nut 62 and housing 63 play a vital role in the laser radar device. Their close connection with other components together ensures the reliability and stability of the implementation of the dual-axis scanning laser radar device.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the claims of the present invention.

Claims

1. A dual-axis scanning laser radar device, characterized in that: It includes a laser emitting unit, a reflecting unit, a receiving unit and a data processing unit; the laser emitting unit is used to generate and emit a laser beam; the reflecting unit is used to realize independent deflection of the laser beam in the horizontal and vertical directions; the receiving unit is used to receive the echo signal and the reference signal reflected back by the target object, and transmit the reference signal and the echo signal to the data processing unit for demodulation and analysis after coherent superposition, so as to extract the distance, shape and motion information of the target object.

2. A dual-axis scanning laser radar device according to claim 1, characterized in that: The laser emitting unit includes a laser light source, a beam splitter, a collimator and a zoom lens; the laser source is used to generate a stable continuous laser signal, and the laser light beam is divided into a signal light and a reference light through the beam splitter; after the signal light is collimated into a parallel light beam by the collimator, the focal length and diameter of the light beam are adjusted by the zoom lens, so as to control the divergence angle and focus point position of the laser light beam according to the distance condition of the target object; the reference light is used as the local oscillator light in the subsequent signal demodulation process.

3. A dual-axis scanning laser radar device according to claim 2, characterized in that: The reflection unit includes two independently arranged wedge-shaped reflectors, which are respectively used to realize independent deflection of the laser beam in the horizontal and vertical directions; the two wedge-shaped reflectors are respectively driven to rotate by a horizontal motor and a vertical motor, so as to control the deflection of the laser beam in the horizontal and vertical directions, forming a dual-axis scanning mode; the scanning angle and scanning speed of the two wedge-shaped reflectors are dynamically adjusted according to a preset path; the wedge-shaped reflector in the horizontal direction can realize omnidirectional scanning from 0 to 360 degrees, and the wedge-shaped reflector in the vertical direction can realize precise adjustment of ±15 degrees.

4. A dual-axis scanning laser radar device according to claim 3, characterized in that: The receiving unit includes a beam expander, a mixer and a photodetector; the beam expander contains a meniscus lens, which is arranged on the optical path of the echo signal reflected by the target object, and is used to receive the reflected echo signal on the optical path of the echo signal and amplify the receiving diameter of the reflected light beam of the target object, so as to increase the effective aperture of the receiving light beam, thereby improving the receiving efficiency of the echo signal and the signal-to-noise ratio of the mixing signal; the mixer is arranged at the intersection of the reference light and the echo signal light beam, and under the protection of the selection protection shell, the local oscillator light and the echo signal are simultaneously received through the nonlinear element and the local oscillator, and the reference light and the echo signal are coherently superimposed through the coherent demodulation technology in the frequency selection loop, so as to obtain the distance, speed and direction information of the target object; the photodetector is used to convert the coherently demodulated optical signal into an electrical signal, and transmit it to the data processing unit.

5. A dual-axis scanning laser radar device according to claim 4, characterized in that: The data processing unit performs signal demodulation based on the signal received by the mixer, and includes a signal filtering module, a data classification module and a three-dimensional imaging module; the signal filtering module is used to remove background noise and interference signals in the electrical signal transmitted by the receiving unit, and extract effective target signals according to preset threshold conditions; the data classification module analyzes and identifies the distance information of multiple target objects according to the received echo signal strength and phase information of the target objects; The three-dimensional imaging module generates high-precision three-dimensional point cloud data based on the distance and angle information of the target object, and can perform dynamic tracking and trajectory prediction according to the movement characteristics of the target object.

6. A dual-axis scanning laser radar device according to claim 5, characterized in that: The laser radar device also includes a control module, which is used to dynamically adjust the rotation speed and angle of the wedge-shaped reflector in the horizontal and vertical directions according to a predetermined scanning path and environmental information of the target area; the control module can pre-set the scanning path and automatically adjust the scanning speed and angle according to real-time environmental information, thereby ensuring that the laser radar can flexibly respond to complex and changeable detection scenarios.

7. The dual-axis scanning laser radar device according to claim 1, characterized in that: The laser radar device also includes a wireless communication module, which is connected to the data processing unit and is used to transmit processed target object data to an external device to achieve remote monitoring and data analysis.

8. The dual-axis scanning laser radar device according to claim 1, characterized in that: The laser radar device also includes an extended function module, which includes a plurality of laser processing units; the laser emitted by the laser emitting unit passes through the laser processing units and then reaches the reflection unit; the laser processing unit includes a beam expander, a light guide column, a focusing mirror and a beam shaper connected in sequence; The beam expander is used to expand the diameter of the laser beam and increase the effective detection area; the light guide column guides and transmits light in the optical path to ensure that the optical signal can propagate along a predetermined path; the focusing mirror enables the light emitted by the laser emitting unit to be smoothly and continuously converged to one point; the beam shaper forms a multi-channel laser beam detection mode to improve the detection speed and resolution.

9. The dual-axis scanning laser radar device according to claim 1, characterized in that: The laser radar device also includes a shell, and the laser emitting unit, the reflecting unit, the receiving unit and the data processing unit are positioned and fixed inside the shell by means of clamps and nuts, and the shell is tightly combined with the laser emitting unit, the reflecting unit, the receiving unit and the data processing unit by means of a snap-on connection.

10. The dual-axis scanning laser radar device according to claim 1, characterized in that: The laser radar device also includes a GNSS module and an IMU module connected to the control module to achieve precise measurement.

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