Micron-sized high-precision automatic three-dimensional positioning device and positioning method based on frequency interference and binocular vision

Abstract

The invention discloses a micron-sized high-precision automatic three-dimensional positioning device and method based on frequency interference and binocular vision, and the device comprises a horizontal and pitching rotary table, a distance measurement module, a binocular vision positioning module, and a multi-station networking control system. Calculating relative orientation parameters between hosts; a frequency scanning interference ranging module of the host is driven by the rotary table to align with the same target ball to obtain high-precision ranging data; and based on the relative orientation parameters and the multi-station distance measurement data, calculating three-dimensional space coordinates of the target ball through a forward intersection adjustment algorithm. According to the invention, through adjusting contrast light and shade information, target ball image information with high reflection brightness is obtained, according to binocular vision positioning information, a horizontal angle and a pitching angle of a point location relative to a current distance measurement module are calculated, angle information is transmitted to a rotary table, the distance measurement module is guided to align a corresponding target ball, and automatic target searching and align functions are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of laser precision three-dimensional measurement, and specifically relates to a micron-level high-precision automatic three-dimensional positioning device and a positioning method based on frequency interference and binocular vision. Background Art

[0002] Frequency Scanning Interferometry (FSI) technology has become one of the key technologies in the field of precision industrial measurement due to its excellent ranging accuracy, compact design, ability to measure without cooperative targets, and strong adaptability to complex environments. This technology relies on tunable lasers to achieve high-precision measurement of absolute distance. Compared with traditional laser interferometry methods, FSI uses lasers with adjustable wavelengths as light sources, which not only improves the measurement accuracy, but also enhances the ability to measure diffuse reflections on non-cooperative targets, thereby maintaining high measurement accuracy and reliability in a wider range of environments.

[0003] In FSI systems, semiconductor tunable lasers are currently the most commonly used type of light source. These lasers vary according to their tuning range, bandwidth, and linewidth, so users can choose the most suitable laser model according to specific application requirements. However, despite the many advantages of FSI technology, it also has certain limitations. For example, FSI can only provide absolute distance information to the target that is currently being precisely aimed at, which means that in scenarios where multi-point measurements are being made or multiple FSI devices are required to work together, the laser beams of each device must be manually adjusted to ensure that they are correctly aligned with their respective measurement targets, which undoubtedly increases the complexity and time cost of the operation. In order to overcome this limitation, technicians in this field are exploring new methods and technologies to improve the flexibility and efficiency of FSI systems and make them more suitable for a variety of industrial applications. Summary of the invention

[0004] The main purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art, and to provide a micron-level high-precision automatic three-dimensional positioning device and positioning method based on frequency interference and binocular vision, based on the high-precision ranging information obtained by frequency scanning interference technology, using multi-position ranging networking forward intersection technology, and adding an automatic target search algorithm to realize batch high-precision coordinate information collection of multiple points in space.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision, comprising two or more hosts, each of which comprises:

[0007] A horizontal and tilting turntable having a horizontal rotation axis and a tilting rotation axis;

[0008] The distance measuring module is fixedly mounted on the rotating mechanism of the horizontal and pitch turntable, and is used to emit frequency modulated laser to the target sphere and receive the reflected signal, and obtain the absolute distance value to the target sphere by solving the interference fringes;

[0009] A binocular vision positioning module is fixedly mounted on the rotating mechanism of the horizontal and pitch turntable, and includes two calibrated image sensors for identifying the pixel position of the target sphere and outputting the horizontal angle and the pitch angle to the horizontal and pitch turntable;

[0010] The multi-station networking control system is used to calculate the horizontal angle and pitch angle of the point relative to the current distance measurement module according to the binocular vision positioning information obtained by the binocular vision positioning module, and transmit the angle information to the horizontal and pitch turntables to guide the distance measurement module to aim at the corresponding target ball, thus realizing the automatic target search and aiming function;

[0011] The two or more hosts work together in the following ways:

[0012] The binocular vision positioning module of each host synchronously observes the common target ball and solves the relative orientation parameters between the hosts;

[0013] The frequency scanning interferometric ranging modules of each host are aimed at the same target ball under the drive of the turntable to obtain high-precision ranging data;

[0014] Based on the relative orientation parameters and multi-station ranging data, the three-dimensional spatial coordinates of the target sphere are solved by a forward intersection adjustment algorithm.

[0015] As a preferred technical solution, the distance measurement module includes a tunable injection laser, a dual beam splitter and a sensor; the tunable laser outputs a wavelength-adjustable laser, which is divided into a measurement optical path and a reference optical path by the beam splitter;

[0016] The measuring optical path illuminates the target sphere through the circulator and the collimator, and the reflected signal forms interference fringes with the reference optical path in the optical sensor after returning; the optical sensor calculates the absolute distance value by solving the phase change of the interference fringes, and the formula is:

[0017]

[0018] Where Δ is the laser sweep rate and F is the interference fringe frequency.

[0019] As a preferred technical solution, the binocular vision positioning module includes two image sensors, which are calibrated to obtain the relative position relationship and the orientation elements in each camera, obtain the position of the target ball in the current field of view and the approximate value of the global reference coordinates, inversely calculate the relative horizontal angle and vertical angle relative to the binocular vision positioning module, and pass them to the turntable drive ranging module to aim at the target ball.

[0020] As a preferred technical solution, the target ball is used to reflect the laser beam of the ranging module; the target ball is a homogeneous glass ball, and an embedded spherical layer is made of glass microbeads inside to achieve high-contrast reflection under the binocular vision positioning field of view to facilitate determination of the pixel position of the target ball.

[0021] As a preferred technical solution, in the multi-station networking control system, the initial parameter values ​​are calculated through the binocular vision positioning module in combination with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle, horizontal angle and distance of the target sphere to obtain the approximate coordinates of the target point in the reference coordinate system.

[0022] As a preferred technical solution, the horizontal rotation range of the horizontal and pitch turntables is 360°, and the pitch rotation range is not less than 270°.

[0023] In a second aspect, the present invention provides a positioning method for a micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision, comprising the following steps:

[0024] S1. The injected tunable laser is divided into a measuring beam and a local oscillator beam after passing through a beam splitter. The local oscillator beam enters the detector through a delayed optical fiber with a fixed optical path. The measuring beam irradiates the target after passing through a circulator and a collimator. After the return signal, it re-enters the collimator and the circulator to reach the detector and merges with the local oscillator beam to generate interference. The absolute distance measurement value is calculated based on the tunable laser center frequency, line width, light speed, optical path, interference fringe phase and instantaneous frequency;

[0025] S2, obtain the image of the measurement area under the current field of view, and obtain the image information of the target ball with high reflective brightness by adjusting the contrast and brightness information. According to the binocular vision positioning information obtained by the binocular vision positioning module, calculate the horizontal angle and pitch angle of the point relative to the current ranging module, and transmit the angle information to the horizontal and pitch turntables to guide the ranging module to aim at the corresponding target ball, so as to realize the automatic target search and aiming function;

[0026] S3. After obtaining the absolute distance information from the spatial multi-points to each measurement module, the coordinates of the spatial multi-points in the current reference system are calculated through forward intersection adjustment.

[0027] As a preferred technical solution, in step S1, the absolute distance measurement information is calculated as follows:

[0028] The interference fringe phase φ(t) and instantaneous frequency f(t) are obtained by phase differentiation as follows:

[0029] φ(t)=2πL(t)v(t) / c;

[0030]

[0031] Where v(t) is the laser center frequency, w is the line width, c is the speed of light, and L(t) is the optical path;

[0032] The optical path difference is twice the actual measured distance x.

[0033]

[0034] Assume the fixed sweep rate is Δv(t)=v 0 Substitute +Δ·t into the instantaneous frequency calculation formula to obtain the absolute distance information x:

[0035]

[0036] As a preferred technical solution, step S2 is specifically as follows:

[0037] In a binocular vision system, the depth of an object is determined by calculating the disparity of homologous points in two camera images. The disparity d is calculated by the following formula:

[0038]

[0039] Where f is the focal length of the camera, X c and Z c are the coordinates in the camera coordinate system;

[0040]

[0041] The pixel position deviation of the same scene imaged by two cameras is the disparity. Through binocular correction, the depth estimation is converted into feature point matching and disparity calculation, where the relationship between disparity d and depth Z is:

[0042]

[0043] Therefore, the image of the target scene is captured through the binocular camera, and its internal and external parameters are given in combination with camera calibration. The distortion is eliminated in combination with stereo correction to complete the matching. Finally, the binocular vision system can extract the position and direction information of the object in three-dimensional space from the images of the two cameras.

[0044] As a preferred technical solution, step S3 is specifically as follows:

[0045] Using the high-precision ranging observations from the instrument to the target sphere, combined with redundant observations from multiple stations, a rigorous overall least squares adjustment is performed to obtain the three-dimensional spatial coordinates of the target sphere with high precision and reliability. The specific process is as follows:

[0046] From a point i in space to the measurement center q of the ranging module 0 Distance

[0047]

[0048] Among them, x i ,y i ,z i is the global three-dimensional coordinate of a point i in space, Measure the center q of the ranging module 0 The global three-dimensional coordinates of

[0049] Construct the observation equation:

[0050]

[0051] in, From a point i in space to the measurement center q of the ranging module 0 The absolute distance measurement observation value of

[0052] Nonlinear equations need to be linearized and then solved by least squares parameters:

[0053]

[0054] X=[δx i ,δy i ,δz i ] T ;

[0055]

[0056] Where V is the absolute range observation residual, is the approximate global three-dimensional coordinate of a point i in space, δx i ,δy i ,δz i is the correction number of the approximate global three-dimensional coordinates of a point i in space, is the least square adjustment constant term of the current observation equation, and P is the observation value weight matrix;

[0057] The weight matrix P is determined according to the distance from the point to the module:

[0058]

[0059] The initial value of the parameter is calculated by binocular vision positioning, combined with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle of the aiming target reflector ball. Horizontal angle θ and distance Get the approximate coordinates of the target point in the reference coordinates.

[0060] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0061] The present invention provides a micron-level high-precision automatic three-dimensional positioning device and positioning method based on frequency interference and binocular vision, which has significant advantages and effects compared with traditional interference ranging methods:

[0062] Improved efficiency: Abandoning the limitations of manually guided measurement, the work efficiency in the measurement process is greatly improved through automated target recognition and aiming technology, especially in scenarios where frequent repeated measurements are required, the advantages are more obvious.

[0063] Improved accuracy: High-contrast image processing technology is used to highlight the target sphere, and binocular vision positioning information is combined to accurately calculate the target's attitude angle relative to the ranging module, ensuring the accuracy of alignment, thereby improving the overall measurement accuracy.

[0064] Simplified operation: It realizes an integrated process from image acquisition, target recognition to angle calculation and automatic aiming, reduces human intervention, simplifies operation steps, and enables non-professionals to easily complete complex measurement tasks.

[0065] Strong adaptability: This method can adapt to the measurement needs in different environments. Through real-time processing of images in the field of view, it can stably and reliably identify and aim at the target even when the lighting conditions change.

[0066] High degree of automation: The entire system design is based on automation, which not only realizes the automatic target search and aiming functions, but also can transmit the calculated angle information to the turntable to achieve precise control of the ranging module, greatly improving the automation level of the measurement work.

[0067] In summary, the present invention provides an efficient, accurate and easy-to-operate multi-point distance measurement solution, which is suitable for various applications requiring fast and accurate distance measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0069] Figure 1 It is a schematic structural diagram of a micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to an embodiment of the present invention;

[0070] Figure 2 For the embodiment of the present invention Figure 1 Schematic diagram of the structure of a single host;

[0071] Figure 3 Schematic diagram of binocular vision positioning according to an embodiment of the present invention;

[0072] Figure 4 is a schematic diagram of a target ball according to an embodiment of the present invention;

[0073] Figure 5 It is a flow chart of a positioning method according to an embodiment of the present invention.

[0074] Explanation of the accompanying figures: 1. Horizontal and elevation turntable; 2. Distance measurement module; 3. Binocular vision positioning module; 4. Target ball; 401. Homogeneous glass ball; 402. Embedded spherical layer. DETAILED DESCRIPTION

[0075] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0076] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0077] like Figure 1 , Figure 2 As shown, this embodiment provides a micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision, including two or more hosts, each host has a horizontal and pitch turntable 1, a ranging module 2, a binocular vision positioning module 3 and a multi-station networking control system; the present invention uses the high-precision ranging information obtained by the ranging module based on the frequency scanning interference technology, adopts the multi-position ranging networking forward intersection technology, and adds an automatic target search method to realize batch high-precision coordinate information collection of multiple points in space.

[0078] Furthermore, the horizontal and tilt turntable 1 has a horizontal rotation axis and a tilt rotation axis; its horizontal rotation range is 360°, and its tilt rotation range is not less than 270°.

[0079] In a specific example, the horizontal and pitch turntable includes a base and a bracket, the bracket is arranged on the base, a turntable is provided between the base and the bracket, and the bracket can achieve 360° rotation within the horizontal range with the turntable; the bracket is provided with a ranging module 2 and a binocular vision positioning module 3, which are arranged on the bracket in an articulated manner through a carrier, thereby achieving a rotation of not less than 270° within the vertical range.

[0080] Furthermore, the distance measuring module 2 is fixedly mounted on the rotating mechanism of the horizontal and pitch turntable 1, and is used to emit frequency modulated laser to the target sphere 4 and receive the reflected signal, and obtain the absolute distance value to the target sphere by solving the interference fringes.

[0081] Furthermore, the distance measurement module 2 includes a tunable injection laser, a dual beam splitter and a sensor; after the measurement light path and the reference light path are transmitted, interference is formed in the sensor and the absolute distance measurement information between the module and the target ball 4 is obtained by calculation, such as Figure 3 As shown, the details are as follows:

[0082] The tunable laser outputs wavelength-tunable laser light, which is divided into a measurement light path and a reference light path by a beam splitter;

[0083] The measuring light path illuminates the target sphere 4 through the circulator and the collimator, and the reflected signal forms interference fringes with the reference light path in the optical sensor after returning; the optical sensor calculates the absolute distance value by solving the phase change of the interference fringes, and the formula is:

[0084]

[0085] Where Δ is the laser sweep rate and F is the interference fringe frequency.

[0086] Furthermore, the binocular vision positioning module 3 includes two image sensors, which are calibrated to obtain the relative position relationship and the orientation elements in each camera, obtain the position of the target ball in the current field of view and the approximate value of the global reference coordinates, inversely calculate the relative horizontal angle and vertical angle relative to the binocular vision positioning module, and pass them to the turntable drive ranging module to aim at the target ball.

[0087] Further, such as Figure 4As shown in parts (a) and (b), the target ball 4 is characterized by a homogeneous glass ball 401, which can reflect the laser beam of the frequency scanning interference ranging module 1 with high intensity; the embedded spherical layer 402 is made of glass microbeads inside to achieve high-contrast reflection under the binocular vision positioning field of view, which is convenient for determining the pixel position of the target ball.

[0088] It is understandable that glass beads are currently widely used raw materials in the field of industrial manufacturing. The size of glass beads is from a few microns to tens of microns. They have good reflective properties and can reflect parallel light along the original light path. At present, all kinds of reflective products are made of glass beads as coating materials. By coating the glass beads inside the glass balls, the glass beads can reflect parallel incident light along the original direction, achieving high reflectivity of interference lasers and brightness differences for binocular vision target search.

[0089] Furthermore, the multi-station networking control system is used to calculate the horizontal angle and pitch angle of the point relative to the current ranging module based on the binocular vision positioning information obtained by the binocular vision positioning module, and transmit the angle information to the horizontal and pitch turntables to guide the ranging module to aim at the corresponding target ball, thereby realizing automatic target search and aiming functions.

[0090] The method comprises the following steps: a multi-lateral forward intersection measurement network is constructed by using a multi-frequency scanning interferometer ranging module 2, a binocular vision positioning module 3 and a horizontal and pitch turntable 1 to form an integrated ranging positioning module; after batch automatic acquisition of absolute ranging information of multi-point target balls relative to each integrated module and their approximate coordinates in a reference coordinate system, based on a least squares adjustment criterion, relative distance weighting is used to perform adjustment calculation to obtain the adjusted coordinates of the multi-points in the reference coordinate system, thereby completing multi-point three-dimensional high-precision and high-efficiency acquisition.

[0091] It can be understood that in the multi-station network control system, the initial parameter values ​​are calculated through the binocular vision positioning module in combination with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle, horizontal angle and distance of the target sphere to obtain the approximate coordinates of the target point in the reference coordinate system.

[0092] like Figure 5 As shown, in another embodiment of the present application, a positioning method of a micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision is also provided, which specifically includes the following steps:

[0093] Step S1, the injected tunable laser is divided into a measuring beam and a local oscillator beam after passing through a spectrometer, the local oscillator beam enters the detector through a delayed optical fiber with a fixed optical path, the measuring beam irradiates the target after passing through a circulator and a collimator, and the return signal re-enters the collimator and the circulator to reach the detector and merges with the local oscillator beam to generate interference, and the absolute distance measurement information is calculated based on the tunable laser center frequency, line width, light speed, optical path, interference fringe phase and instantaneous frequency.

[0094] Furthermore, the absolute distance information is calculated as follows:

[0095] The interference fringe phase φ(t) and instantaneous frequency f(t) are obtained by phase differentiation as follows:

[0096] φ(t)=2πL(t)v(t) / c;

[0097]

[0098] Where v(t) is the laser center frequency, w is the line width, c is the speed of light, and L(t) is the optical path;

[0099] The optical path difference is twice the actual measured distance x.

[0100]

[0101] Assume the fixed sweep rate is Δv(t)=v 0 Substitute +Δ·t into the instantaneous frequency calculation formula to obtain the absolute distance information x:

[0102]

[0103] In practical applications, based on this principle and combined with the influence of factors such as the actual laser measurement environment, it is necessary to adopt a specific method of adding a reference optical path to eliminate the nonlinear error of light source tuning.

[0104] Step S2, automatically searching for a target and aiming;

[0105] In the actual measurement process of multi-point ranging, the efficiency of traditional interferometric ranging and other methods is mainly affected by manual guided measurement. Automatic target search can greatly improve efficiency and has more efficiency advantages in repeated measurement. The image of the measurement area under the current field of view is obtained, and the image information of the target ball with high reflective brightness is obtained by adjusting the contrast and brightness information. According to the binocular vision positioning information obtained by the binocular vision positioning module, the horizontal angle and pitch angle of the point relative to the current ranging module are calculated, and the angle information is passed to the horizontal and pitch turntables to guide the ranging module to aim at the corresponding target ball, realizing the automatic target search and aiming function.

[0106] Furthermore, step S2 is specifically as follows:

[0107] In a binocular vision system, the depth of an object is determined by calculating the disparity of homologous points in two camera images. The disparity d is calculated by the following formula:

[0108]

[0109] Where f is the focal length of the camera, X c and Z c are the coordinates in the camera coordinate system;

[0110]

[0111] The pixel position deviation of the same scene imaged by two cameras is the disparity. Through binocular correction, the depth estimation is converted into feature point matching and disparity calculation, where the relationship between disparity d and depth Z is:

[0112]

[0113] Therefore, the image of the target scene is captured through the binocular camera, and its internal and external parameters are given in combination with camera calibration. The distortion is eliminated in combination with stereo correction to complete the matching. Finally, the binocular vision system can extract the position and direction information of the object in three-dimensional space from the images of the two cameras.

[0114] With the above steps and formulas, the binocular vision system can extract the position and direction information of the object in three-dimensional space from the images of two cameras.

[0115] S3, after obtaining the absolute distance information from the spatial multi-points to each measurement module, the coordinates of the spatial multi-points in the current reference system are calculated by forward intersection adjustment; specifically:

[0116] Using the high-precision ranging observations from the instrument to the target sphere, combined with redundant observations from multiple stations, a rigorous overall least squares adjustment is performed to obtain the three-dimensional spatial coordinates of the target sphere with high accuracy and reliability. The specific process is as follows:

[0117] From a point i in space to the measurement center q of the ranging module 0 Distance

[0118]

[0119] Among them, x i ,y i ,z i is the global three-dimensional coordinate of a point i in space, Measure the center q of the ranging module 0 The global three-dimensional coordinates of

[0120] Construct the observation equation:

[0121]

[0122] in, From a point i in space to the measurement center q of the ranging module 0 The absolute distance measurement observation value of

[0123] Nonlinear equations need to be linearized and then solved by least squares parameters:

[0124]

[0125] X=[δx i ,δy i ,δz i ] T ;

[0126]

[0127]

[0128] Where V is the absolute range observation residual, is the approximate global three-dimensional coordinate of a point i in space, δx i ,δy i ,δz i is the correction number of the approximate global three-dimensional coordinates of a point i in space, is the least square adjustment constant term of the current observation equation, and P is the observation value weight matrix;

[0129] The weight matrix P is determined according to the distance from the point to the module:

[0130]

[0131] The initial value of the parameter is calculated by binocular vision positioning, combined with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle of the aiming target reflector ball. Horizontal angle θ and distance Get the approximate coordinates of the target point in the reference coordinates.

[0132] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0133] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision, characterized in that: Includes two or more hosts, each of which includes: A horizontal and tilting turntable having a horizontal rotation axis and a tilting rotation axis; The distance measuring module is fixedly mounted on the rotating mechanism of the horizontal and pitch turntable, and is used to emit frequency modulated laser to the target sphere and receive the reflected signal, and obtain the absolute distance value to the target sphere by solving the interference fringes; A binocular vision positioning module is fixedly mounted on the rotating mechanism of the horizontal and pitch turntable, and includes two calibrated image sensors for identifying the pixel position of the target sphere and outputting the horizontal angle and the pitch angle to the horizontal and pitch turntable; The multi-station networking control system is used to calculate the horizontal angle and pitch angle of the point relative to the current distance measurement module according to the binocular vision positioning information obtained by the binocular vision positioning module, and transmit the angle information to the horizontal and pitch turntables to guide the distance measurement module to aim at the corresponding target ball, thus realizing the automatic target search and aiming function; The two or more hosts work together in the following ways: The binocular vision positioning module of each host synchronously observes the common target ball and solves the relative orientation parameters between the hosts; The frequency scanning interferometric ranging modules of each host are aimed at the same target ball under the drive of the turntable to obtain high-precision ranging data; Based on the relative orientation parameters and multi-station ranging data, the three-dimensional spatial coordinates of the target sphere are solved by a forward intersection adjustment algorithm.

2. According to claim 1, the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision is characterized in that: The distance measurement module includes a tunable injection laser, a dual beam splitter and a sensor; the tunable laser outputs a wavelength-adjustable laser, which is divided into a measurement optical path and a reference optical path by the beam splitter; The measuring optical path illuminates the target sphere through the circulator and the collimator, and the reflected signal forms interference fringes with the reference optical path in the optical sensor after returning; the optical sensor calculates the absolute distance value by solving the phase change of the interference fringes, and the formula is: Where Δ is the laser sweep rate and F is the interference fringe frequency.

3. According to claim 1, the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision is characterized in that: The binocular vision positioning module includes two image sensors, which are calibrated to obtain the relative position relationship and the orientation elements in each camera, obtain the position of the target ball in the current field of view and the approximate value of the global reference coordinates, inversely calculate the relative horizontal angle and vertical angle relative to the binocular vision positioning module, and transmit them to the turntable drive ranging module to aim at the target ball.

4. According to claim 1, the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision is characterized in that: The target ball is used to reflect the laser beam of the ranging module; the target ball is a homogeneous glass ball, and the internal glass microbeads are used to make an embedded spherical layer to achieve high-contrast reflection under the binocular vision positioning field of view, so as to facilitate the determination of the pixel position of the target ball.

5. According to claim 1, the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision is characterized in that: In the multi-station networking control system, the initial parameter values ​​are calculated by the binocular vision positioning module in combination with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle, horizontal angle and distance of the sighting target sphere to obtain the approximate coordinates of the target point in the reference coordinate system.

6. The micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to claim 1 is characterized in that: The horizontal rotation range of the horizontal and elevation turntables is 360°, and the elevation rotation range is not less than 270°.

7. The positioning method of the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to any one of claims 1 to 6, characterized in that: The steps include: S1. The injected tunable laser is divided into a measuring beam and a local oscillator beam after passing through a beam splitter. The local oscillator beam enters the detector through a delayed optical fiber with a fixed optical path. The measuring beam irradiates the target after passing through a circulator and a collimator. After the return signal, it re-enters the collimator and the circulator to reach the detector and merges with the local oscillator beam to generate interference. The absolute distance measurement value is calculated based on the tunable laser center frequency, line width, light speed, optical path, interference fringe phase and instantaneous frequency; S2, obtain the image of the measurement area under the current field of view, and obtain the image information of the target ball with high reflective brightness by adjusting the contrast and brightness information. According to the binocular vision positioning information obtained by the binocular vision positioning module, calculate the horizontal angle and pitch angle of the point relative to the current ranging module, and transmit the angle information to the horizontal and pitch turntables to guide the ranging module to aim at the corresponding target ball, so as to realize the automatic target search and aiming function; S3. After obtaining the absolute distance information from the spatial multi-points to each measurement module, the coordinates of the spatial multi-points in the current reference system are calculated through forward intersection adjustment.

8. The positioning method of the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to claim 7 is characterized in that: In step S1, the absolute distance information is calculated as follows: The interference fringe phase φ(t) and instantaneous frequency f(t) are obtained by phase differentiation as follows: φ(t)=2πL(t)v(t) / c; Where v(t) is the laser center frequency, w is the line width, c is the speed of light, and L(t) is the optical path; The optical path difference is twice the actual measured distance x. Assume that the fixed frequency sweep rate is Δv(t)=v0+Δ·t and substitute it into the instantaneous frequency calculation formula to obtain the absolute distance information x:

9. The positioning method of the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to claim 7, characterized in that: Step S2 is specifically as follows: In a binocular vision system, the depth of an object is determined by calculating the disparity of homologous points in two camera images. The disparity d is calculated by the following formula: Where f is the focal length of the camera, X c and Z c are the coordinates in the camera coordinate system; The pixel position deviation of the same scene imaged by two cameras is the disparity. Through binocular correction, the depth estimation is converted into feature point matching and disparity calculation, where the relationship between disparity d and depth Z is: Therefore, the image of the target scene is captured through the binocular camera, and its internal and external parameters are given in combination with camera calibration. The distortion is eliminated in combination with stereo correction to complete the matching. Finally, the binocular vision system can extract the position and direction information of the object in three-dimensional space from the images of the two cameras.

10. The positioning method of the micron-level high-precision automatic three-dimensional positioning device based on frequency interference and binocular vision according to claim 7, characterized in that: The step S3 is specifically as follows: Using the high-precision ranging observations from the instrument to the target sphere, combined with redundant observations from multiple stations, a rigorous overall least squares adjustment is performed to obtain the three-dimensional spatial coordinates of the target sphere with high precision and reliability. The specific process is as follows: The distance from a point i in space to the measurement center q0 of the ranging module Among them, x i ,y i ,z i is the global three-dimensional coordinate of a point i in space, The global three-dimensional coordinates of the measurement center q0 of the ranging module; Construct the observation equation: in, is the absolute distance measurement observation value from a certain point i in space to the measurement center q0 of the ranging module; Nonlinear equations need to be linearized and then solved by least squares parameters: X=[δx i ,δy i ,δz i ] T ; Where V is the absolute range observation residual, is the approximate global three-dimensional coordinate of a point i in space, δx i ,δy i ,δz i is the correction number of the approximate global three-dimensional coordinates of a point i in space, is the least square adjustment constant term of the current observation equation, and P is the observation value weight matrix; The weight matrix P is determined according to the distance from the point to the module: The initial value of the parameter is calculated by binocular vision positioning, combined with the known points in space to obtain the coordinates and posture of each ranging module in the current reference coordinate system, and then combined with the vertical angle of the aiming target reflector ball. Horizontal angle θ and distance Get the approximate coordinates of the target point in the reference coordinates.

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