阅读说明：本技术 一种基于图像处理的自动天文定向系统 (Automatic astronomical orientation system based on image processing ) 是由 冯冰砚 刘慧� 王冕 盛永鑫 李燕 包金平 刘莎莎 陈正平 吴孝迎 于 2021-07-28 设计创作，主要内容包括：本发明公开了一种基于图像处理的自动天文定向系统,属于天文导航技术领域,包括计算机、全站仪、工业相机、十轴惯性导航姿态传感器、通信连接盒,所述工业相机、十轴惯性导航姿态传感器设置在所述全站仪纵轴的粗瞄镜上。本发明利用十轴惯性导航姿态传感器输出磁角给全站仪水平方位角概略定向,同时输出时间和经纬度,通过天文算法计算出太阳在地平坐标系下的方位角和天顶距,控制全站仪自动指向太阳,使太阳出现在相机的视场范围内,拍摄太阳图像,通过图像处理提取太阳质心坐标,得到待测目标真北方位角,采用了基于图像处理自动定向的方法,减少了人工干预,操作简单,实现了定向的自动化和快速化。(The invention discloses an automatic astronomical orientation system based on image processing, which belongs to the technical field of astronomical navigation and comprises a computer, a total station, an industrial camera, a ten-axis inertial navigation attitude sensor and a communication connection box, wherein the industrial camera and the ten-axis inertial navigation attitude sensor are arranged on a coarse sighting telescope of a longitudinal axis of the total station. The invention utilizes a ten-axis inertial navigation attitude sensor to output a magnetic angle to roughly orient a horizontal azimuth angle of a total station, and simultaneously outputs time and longitude and latitude, calculates an azimuth angle and zenith distance of the sun under a horizon coordinate system through an astronomical algorithm, controls the total station to automatically point to the sun, enables the sun to appear in a field range of a camera, shoots a sun image, extracts a sun centroid coordinate through image processing, and obtains a true north azimuth angle of a target to be measured.)

1. An automatic astronomical orientation system based on image processing, characterized in that: the system comprises a computer, a total station, an industrial camera, a ten-axis inertial navigation attitude sensor and a communication connection box, wherein the industrial camera and the ten-axis inertial navigation attitude sensor are arranged on a coarse sighting telescope of a longitudinal axis of the total station, the industrial camera and the ten-axis inertial navigation attitude are in communication connection with the computer through the communication connection box, and the total station is in communication connection with the computer.

2. An automatic astronomical orientation system based on image processing according to claim 1, wherein: the computer is communicated with the total station through a serial port, and the computer is communicated with the communication connection box through a network.

3. An automatic astronomical orientation system based on image processing according to claim 1, wherein: the communication connection box comprises a power supply module and a serial server, the power supply module is used for supplying power to the serial server and the ten-axis inertial navigation attitude sensor, and the serial server is used for converting a serial port into a network interface, serving as a network switch and supplying PoE power to the industrial camera.

4. An automatic astronomical orientation system based on image processing according to claim 1, wherein: the total station is provided with a motor driving assembly, and the total station is controlled to rotate along the horizontal direction and the vertical direction through the motor driving assembly.

5. An automatic astronomical orientation system based on image processing according to claim 3, wherein: the ten-axis inertial navigation attitude sensor is powered by the 5VDC converted by the power supply module, is used for receiving BDS, GPS and GLONASS signals and outputting time, longitude and latitude and magnetic angle data.

6. An automatic astronomical orientation system based on image processing according to claim 1, wherein: the industrial camera and the ten-axis inertial navigation attitude sensor are connected with the communication connection box through a one-to-two communication cable.

7. An automatic astronomical orientation method based on image processing, which is characterized in that an automatic astronomical orientation system according to any one of claims 1-6 is adopted to carry out orientation work on an object to be measured, and comprises the following steps:

s1: the ten-axis inertial navigation attitude sensor outputs time, longitude and latitude and a magnetic angle, the output magnetic angle is utilized to roughly orient the horizontal azimuth of the total station, and meanwhile, the computer acquires the horizontal azimuth of the total station;

s2: calculating a horizontal azimuth angle and a zenith distance of the sun under a horizon coordinate system at this time through an astronomical algorithm, driving a motor driving component on the total station to control the total station to aim at the sun, shooting a sun image, and simultaneously recording shooting time;

s3: and calculating the true north azimuth angle of the sun at the moment by using an astronomical algorithm, obtaining the horizontal azimuth angle of the solar centroid in the total station through the conversion relation between the pixel coordinates (u, v) of the industrial camera and the coordinates (x1, y1, z1) of the total station, and simultaneously measuring the horizontal azimuth angle of the target to be measured by using the total station, thereby obtaining the horizontal azimuth angle difference value of the target to be measured and the solar centroid in the coordinate system of the total station and further obtaining the true north azimuth angle of the target to be measured.

8. The automatic astronomical orientation method based on image processing of claim 7, wherein: in said step S3, the industrial camera pixel coordinates (u, v) and the total station coordinates (x)₁,y₁,z₁) The conversion of (a) is shown as follows:

in the formula (u)₀,v₀) Pixel coordinates representing the center of the image, dx dy representing the physical size of the picture elements in the photosensitive element of the industrial camera, R₁、T₁Representing a rotation and translation matrix from a total station longitudinal axis coordinate system to a total station coordinate system, R2 and T2 representing rotation and translation matrices from a camera coordinate system to the total station longitudinal axis coordinate system, Z_CRepresenting the object distance and f the focal length of the camera.

9. The automatic astronomical orientation method based on image processing of claim 7, wherein: in step S3, the process of extracting the solar centroid specifically includes:

s31: carrying out gray processing on a color image shot by an industrial camera;

s32: filtering clutter interference by using a Gaussian low-pass filter;

s33: image segmentation is carried out by adopting a method of automatically calculating a threshold value;

s34: after the gray level of the image is binarized, a circular structural element with the radius of 5 pixels is created for opening operation;

s35: and (5) carrying out edge detection and extracting the center of mass of the sun.

Technical Field

The invention relates to the technical field of astronomical navigation, in particular to an automatic astronomical orientation system based on image processing.

Background

When the existing astronomical orientation system based on image processing uses a camera to shoot a solar target, the sun needs to be in a view field range of the camera through human eye observation or other sun is observed to give a total station horizontal azimuth angle rough orientation, the systems can not leave the operation of personnel, a real automatic astronomical orientation system can not be calculated, a differential GPS is arranged on the total station to give the total station horizontal azimuth angle rough orientation, and the total station is provided with the GPS with large mass and volume and a complex structure. To this end, an automatic astronomical orientation system based on image processing is proposed.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: how to solve the problems that the existing astronomical orientation device has a complex structure and needs to be operated by personnel and the like, and provides an automatic astronomical orientation system based on image processing.

The invention solves the technical problems through the following technical scheme, and the system comprises a computer, a total station, an industrial camera, a ten-axis inertial navigation attitude sensor and a communication connection box, wherein the industrial camera and the ten-axis inertial navigation attitude sensor are arranged on a coarse sight lens of a longitudinal axis of the total station, the industrial camera and the ten-axis inertial navigation attitude sensor are in communication connection with the computer through the communication connection box, and the total station is in communication connection with the computer.

Further, the computer is communicated with the total station through a serial port, and the computer is communicated with the communication connection box through a network.

Furthermore, the communication connection box comprises a power supply module and a serial server, wherein the power supply module is used for supplying power to the serial server and the ten-axis inertial navigation attitude sensor, and the serial server is used for converting a serial port into a network interface, serving as a network switch and supplying PoE power to the industrial camera.

Furthermore, a motor driving assembly is arranged on the total station, and the total station is controlled to rotate in the horizontal and vertical directions through the motor driving assembly.

Furthermore, the ten-axis inertial navigation attitude sensor is powered by the 5VDC converted by the power supply module, and is used for receiving BDS, GPS and GLONASS signals and outputting time, longitude and latitude and magnetic angle data.

Furthermore, the industrial camera and the ten-axis inertial navigation attitude sensor are connected with the communication connection box through a two-in-one communication cable connection.

The invention also provides an automatic astronomical orientation method based on image processing, which adopts the automatic astronomical orientation system to orient an object to be measured and comprises the following steps:

s1: the ten-axis inertial navigation attitude sensor outputs time, longitude and latitude and a magnetic angle, the output magnetic angle is utilized to roughly orient the horizontal azimuth of the total station, and meanwhile, the computer acquires the horizontal azimuth of the total station;

s2: calculating a horizontal azimuth angle and a zenith distance of the sun under a horizon coordinate system at this time through an astronomical algorithm, driving a motor driving component on the total station to control the total station to aim at the sun, shooting a sun image, and simultaneously recording shooting time;

s3: and calculating the true north azimuth angle of the sun at the moment by using an astronomical algorithm, obtaining the horizontal azimuth angle of the solar centroid in the total station through the conversion relation between the pixel coordinates (u, v) of the industrial camera and the coordinates (x1, y1, z1) of the total station, and simultaneously measuring the horizontal azimuth angle of the target to be measured by using the total station, thereby obtaining the horizontal azimuth angle difference value of the target to be measured and the solar centroid in the coordinate system of the total station and further obtaining the true north azimuth angle of the target to be measured.

Further, in the step S3, the industrial camera pixel coordinates (u, v) and the total station coordinates (x)₁,y₁,z₁) The conversion of (a) is shown as follows:

in the formula (u)₀,v₀) Pixel coordinates representing the center of the image, dx dy representing the physical size of the picture elements in the photosensitive element of the industrial camera, R₁、T₁Representing a rotation and translation matrix from a total station longitudinal axis coordinate system to a total station coordinate system, R2 and T2 representing rotation and translation matrices from a camera coordinate system to the total station longitudinal axis coordinate system, Z_CRepresenting the object distance and f the focal length of the camera.

Further, in the step S3, the process of extracting the solar centroid specifically includes:

s31: carrying out gray processing on a color image shot by an industrial camera;

s32: filtering clutter interference by using a Gaussian low-pass filter;

s33: image segmentation is carried out by adopting a method of automatically calculating a threshold value;

s34: after the gray level of the image is binarized, a circular structural element with the radius of 5 pixels is created for opening operation;

s35: and (5) carrying out edge detection and extracting the center of mass of the sun.

Compared with the prior art, the invention has the following advantages: the automatic astronomical orientation system based on image processing utilizes a ten-axis inertial navigation attitude sensor to output a magnetic angle to a horizontal azimuth angle of a total station for approximate orientation, simultaneously outputs time and longitude and latitude, calculates an azimuth angle and zenith distance of the sun in a horizontal coordinate system through an astronomical algorithm, controls the total station to automatically point to the sun, enables the sun to appear in a view field range of a camera, shoots a sun image, extracts a sun centroid coordinate through image processing, and obtains a true north azimuth angle of a target to be detected.

Drawings

FIG. 1 is a schematic diagram of a system according to a second embodiment of the present invention;

FIG. 2 is a diagram of a system hardware architecture according to a second embodiment of the present invention;

fig. 3 is a flowchart of a solar image centroid extraction algorithm in the second embodiment of the present invention.

In the figure: 1. a total station; 2. a computer; 3. a total station longitudinal axis; 4. an adapter plate; 5. a one-to-two communication cable; 6. a communication connection box; 7. a serial communication cable; 8. the sun; 9. and (5) a target to be detected.

Detailed Description

The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.

Example one

The embodiment provides a technical scheme: an automatic astronomical orientation system based on image processing comprises a computer, a total station, an industrial camera, a ten-axis inertial navigation attitude sensor and a communication connection box, wherein the computer is communicated with the total station through a serial port, the computer is communicated with the communication connection box through a network, the industrial camera can be powered by PoE (Power over Ethernet), the industrial camera adopts an adjustable shading mirror, the gray scale is adjusted according to the light intensity of the sun, the ten-axis inertial navigation attitude sensor can be powered by 3.3V-5V, can receive BDS (brain navigation System), GPS (Global positioning System) and GLONASS (global angle of arrival), can output time, longitude and latitude and magnetic angle (magnetic azimuth angle), the industrial camera and the ten-axis inertial navigation attitude sensor are respectively connected with the communication connection box through a network port and a serial port and are connected with the communication connection box through a one-in-two communication cable, the industrial camera and the ten-axis inertial navigation attitude sensor are arranged at the coarse aiming mirror position of the longitudinal axis of the total station through a switching board, the communication connection box comprises a power supply module and a serial server, wherein the power supply module converts 220VAC into 5VDC and 24VDC, the serial server can convert a serial port into a network interface, can be used as a network switch and provide PoE power supply, and calculates the conversion relation between the image pixel coordinate of the industrial camera and the scale coordinate of the total station. The system adopts an automatic orientation method based on image processing, reduces manual intervention, is simple to operate, and realizes automation and rapidness of orientation.

In this embodiment, the total station has a motor drive assembly by which it can be automatically rotated in horizontal and vertical directions.

In this embodiment, the computer and the total station are used to transmit data through serial port communication. Coordinate data measured by the total station are obtained through the serial port communication computer, the total station is automatically aligned to the sun through serial port communication, and a sun image is shot.

In this embodiment, the industrial camera may be powered by PoE, and communicate and power is supplied through a network interface. The industrial camera adopts an adjustable shading mirror to adjust the gray scale according to the light intensity of the sun. The ten-axis inertial navigation attitude sensor is powered by 3.3V-5V, can receive BDS, GPS and GLONASS signals and outputs time, longitude and latitude and magnetic angle. The industrial camera and the ten-axis inertial navigation attitude sensor are respectively connected with the communication connection box through a network port and a serial port.

In this embodiment, the industrial camera and the ten-axis inertial navigation attitude sensor are mounted on a coarse sighting telescope position of a longitudinal axis of the total station through an adapter plate, and are connected to the communication connection box through a one-to-two communication cable. The ten-axis inertial navigation attitude sensor outputs a magnetic angle to the total station to roughly orient the horizontal azimuth angle, the computer program simultaneously collects time and longitude and latitude, the azimuth angle and zenith distance of the sun under the horizontal coordinate system at the moment are calculated through an astronomical algorithm, the total station is controlled to automatically point to the sun, a camera can shoot a sun image, and the center of mass coordinate of the sun is extracted through image processing to obtain a target azimuth angle.

In the present embodiment, the industrial camera pixel coordinates (u, v) and the total station coordinates (x)₁,y₁,z₁) The conversion of (a) is shown as follows:

in the formula (u)₀,v₀) Pixel coordinates representing the center of the image, dx dy representing the physical size of the picture elements in the photosensitive element of the industrial camera, R₁、T₁Representing a rotation and translation matrix from a total station longitudinal axis coordinate system to a total station coordinate system, R2 and T2 representing rotation and translation matrices from a camera coordinate system to the total station longitudinal axis coordinate system, Z_CRepresenting the object distance and f the focal length of the camera.

Example two

As shown in fig. 1, which is a schematic structural diagram of the system of the present invention, an adapter plate 4 is installed at a coarse sighting telescope position of a total station longitudinal axis 3, an industrial camera and a ten-axis inertial navigation attitude sensor are installed on the adapter plate 4, and data is transmitted to a communication connection box 6 through a one-to-two communication cable 5 and then transmitted to a computer 2 through a network cable. The total station 1 and the computer 2 carry out serial port communication through a serial port communication cable 7, and the computer 2 obtains coordinate data and pictures measured by the total station 1 and controls the total station 1 to automatically align to the sun 8. The included angle between the sun 8 and the true north at this time is known through an astronomical algorithm, the data is measured through the total station 1, the position relation between the target 9 to be measured and the sun 8 is obtained through related calculation, the included angle between the target 9 to be measured and the true north is obtained, and the orientation of the target 9 to be measured is completed.

The above-mentioned astronomical orientation algorithm that passes is the sphere positioning triangle formula, the formula is as follows:

cosV＝sinφsinδ+cosφcosδcost

wherein, delta, t and phi are respectively the solar declination, the solar time angle and the station latitude. And obtaining A and V as the true north azimuth angle and the zenith distance of the sun 8 respectively.

In this embodiment, the ten-axis inertial navigation attitude sensor has a size of 73mm 38mm 27mm and a weight of 60 g.

As shown in fig. 2, for the hardware architecture diagram of the system of the present invention, an industrial camera and a ten-axis inertial navigation attitude sensor are installed on a coarse sight lens of a longitudinal axis of a total station through an adapter plate, and are connected to a communication connection box through a one-to-two communication cable, the communication connection box includes a serial server and a power module, the power module supplies power to the serial server and the ten-axis inertial navigation attitude sensor, the serial server communicates with the ten-axis inertial navigation attitude sensor through a serial port, the ten-axis inertial navigation attitude sensor outputs time, longitude and latitude and magnetic azimuth, a computer collects a horizontal azimuth of the total station, and at this time, the magnetic azimuth output by the ten-axis inertial navigation attitude sensor roughly orients the horizontal azimuth of the total station. And calculating a horizontal azimuth angle and a zenith distance of the sun under the horizon coordinate system at this time through an astronomical algorithm, wherein the calculated horizontal azimuth angle and zenith distance of the sun are used as a horizontal azimuth angle and a vertical angle to which the total station needs to rotate, and the total station is driven through a total station control instruction, so that the sun appears in the field range of a camera at this time, a sun image is shot, and the shooting time is recorded at the same time. And calculating the true north azimuth angle of the sun by using the shooting time and the obtained longitude and latitude. The method comprises the steps of extracting a sun centroid through a shot sun image, obtaining a horizontal azimuth angle of the sun centroid in a total station by utilizing a conversion relation between an industrial camera pixel coordinate (u, v) and a total station coordinate (x1, y1, z1), and simultaneously measuring the horizontal azimuth angle of a target to be measured by utilizing the total station, so that a horizontal azimuth angle difference value of the target to be measured and the sun centroid in a total station coordinate system is obtained, and further a true north azimuth angle of the target to be measured is obtained.

As shown in fig. 3, the present invention is a flow chart of the solar image centroid extraction algorithm, which includes the steps of graying a color image, gaussian low-pass filtering, automatically calculating a threshold value, binarizing a grayscale image, performing an opening operation, extracting a solar centroid, etc. The captured solar image is a color image, and the color image is usually grayed out in order to reduce the amount of calculation. And filtering clutter interference by using a Gaussian low-pass filter after the image is grayed. In order to extract the center of mass of the sun, the sun needs to be segmented from the background image, so that the sun image needs to be subjected to threshold segmentation, which is a region segmentation technology and a common preprocessing step in a machine vision system, wherein the gray value of an interested region is higher or lower than that of other elements, and the image is segmented according to the gray value. The histogram of the solar image obtained by the system is a double-peak shape, and the image segmentation can be carried out by adopting a method of automatically calculating a threshold value. And after the image is subjected to gray level binarization, a circular structural element with the radius of 5 pixels is created for opening operation, and finally edge detection is carried out to extract the sun centroid.

To sum up, in the automatic astronomical orientation system based on image processing according to the embodiment, the ten-axis inertial navigation attitude sensor is used for outputting the magnetic angle to roughly orient the horizontal azimuth angle of the total station, and simultaneously outputting the time and the longitude and latitude, the azimuth angle and the zenith distance of the sun in the horizontal coordinate system are calculated through an astronomical algorithm, the total station is controlled to automatically point to the sun, so that the sun appears in the field of view of the camera, the sun image is shot, the centroid coordinate of the sun is extracted through image processing, and the true north azimuth angle of the target to be measured is obtained.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.