CN209842416U

CN209842416U - Sun position tracking device based on image processing

Info

Publication number: CN209842416U
Application number: CN201920571895.2U
Authority: CN
Inventors: 陈宇迪; 李春彪; 陆续
Original assignee: Nanjing University of Information Science and Technology
Current assignee: Nanjing University of Information Science and Technology
Priority date: 2019-04-25
Filing date: 2019-04-25
Publication date: 2019-12-24
Anticipated expiration: 2029-04-25

Abstract

The utility model discloses a sun position tracking device based on image processing, which comprises an energy supply device, a sunlight projection device, an image acquisition device, an image processing and operation device and a data output interface; the sunlight projection device comprises a horizontal curtain and a shading rod vertically erected in the center of the horizontal curtain, the image acquisition device is a camera module arranged below the horizontal curtain, under illumination, the shading rod forms a shadow on the horizontal curtain, the camera module captures image information formed by the shadow and brightness on the back of the horizontal curtain, and the image processing and operation device calculates the sun azimuth angle and the altitude angle through the image information. This device borrows for reference the design of sundial, adds the camera module again, has constituted main measuring part, but the altitude angle and the azimuth of accurate measurement sun, and simple structure is reliable.

Description

Sun position tracking device based on image processing

Technical Field

The utility model belongs to the technical field of the sun position tracking technique and specifically relates to a sun position tracking means based on image processing is related to.

Background

Currently, the solar azimuth refers to an angle between the projection of the solar ray on the ground plane and the local meridian (0 degree in the north direction), or an angle between the shadow of a straight line standing on the ground in the sun and the north direction. The solar altitude angle is the angle between the incident direction of sunlight and the ground plane, or the angle between the sunlight of a certain place and the surface tangent plane connected with the center of the earth through the place.

Solar azimuth and elevation have important practical implications, such as analyzing solar radiation, for solar applications, and the like. Both of these can be formulated to calculate theoretical values, but in some cases, actual values must be measured with instrumentation.

Most of the existing products or patents with similar functions use motors, encoders and the like. This design has significant disadvantages: 1. the structure is complex, a plurality of movable parts are easy to break down, so that the equipment cannot normally work, the maintenance cost is high, the equipment needs to work in an outdoor complex and severe environment and inevitably experiences wind, wind and sunlight, and the possibility of mechanical failure is greatly increased; 2. the power consumed by these devices is typically relatively high and requires an external continuous supply of power; 3. the measurement of the elevation and azimuth angles often requires two separate units, adding to the complexity and manufacturing cost of the device.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: in order to overcome the not enough of background art, the utility model discloses a sun position tracking means based on image processing.

The technical scheme is as follows: the utility model discloses a sun position tracking device based on image processing, which comprises an energy supply device, a sunlight projection device, an image acquisition device, an image processing arithmetic device and a data output interface; the sunlight projection device comprises a horizontal curtain and a shading rod vertically erected in the center of the horizontal curtain, the image acquisition device is a camera module arranged below the horizontal curtain, under illumination, the shading rod forms a shadow on the horizontal curtain, the camera module captures image information formed by the shadow and brightness on the back of the horizontal curtain, and the image processing and operation device calculates the sun azimuth angle and the altitude angle through the image information.

Furthermore, the energy supply device supplies power to the photovoltaic power generation device, the piezoelectric energy harvesting device and the external power supply. The piezoelectric energy harvesting device can convert weak energy such as air flow into electric energy to supplement photovoltaic power generation, and effectively cope with the condition of insufficient illumination. In addition, the DC power supply is externally connected to deal with other unpredictable special conditions.

Furthermore, the projection surface of the horizontal curtain is made of transparent white materials. To ensure that the bright and shaded areas above are clearly visible from below the horizontal screen for receiving the projection of the shaded rod.

Further, the image processing operation device calculates an azimuth angle according to the angle information of the shade of the shading rod, and calculates an altitude angle according to the length information of the shade of the shading rod.

Furthermore, the data output interface is connected with an LCD screen and a USB interface, and the LCD screen can visually display a calculation result; the USB interface may output the results to a computer or other device.

Has the advantages that: compared with the prior art, the utility model has the advantages that: this device borrows for reference the design of sundial, adds the camera module again, has constituted main measurement part, but the altitude angle and the azimuth of accurate measurement sun, and simple structure is reliable, and simultaneously, the measurement of altitude angle and azimuth is accomplished by same device, only relies on two kinds of different algorithms, just can obtain two data. The device has low power consumption, only the low-power consumption singlechip consumes power actually, and the device fully utilizes the energy in the nature to supply power without accessing a power supply under the normal condition.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a flow chart of the present invention;

fig. 3 is an image processing process diagram of the present invention.

Detailed Description

The technical solution of the present invention will be further explained with reference to the accompanying drawings and examples.

The sun position tracking device based on image processing shown in fig. 1 comprises an energy supply device, a sunlight projection device, an image acquisition device, an image processing and calculating device and a data output interface.

The energy supply device supplies power to the photovoltaic power generation device, the piezoelectric energy harvesting device and the external power supply. The energy supply device supplies power to the whole system, wherein the photovoltaic power generation device supplies power to the whole device under illumination. The piezoelectric energy harvesting device can convert weak energy such as air flow into electric energy to supplement photovoltaic power generation, effectively deal with the condition of insufficient illumination, and is externally connected with a DC power supply to deal with other unpredictable special conditions.

Sunlight projection arrangement includes horizontal curtain 1 and erects perpendicularly at the shading pole 2 of horizontal curtain 1 central authorities, the plane of projection of horizontal curtain 1 is transparent white material, image acquisition device is for setting up camera module 3 in horizontal curtain 1 below, and has appropriate distance between the horizontal curtain 1, and central optical axis is perpendicular with horizontal curtain 1 plane, and the bright part and the shadow region of top can be seen clearly from horizontal curtain 1 below for receive the projection that hides the pole. Under the illumination, the light shading rod 2 forms a shadow on the horizontal curtain 1, the camera module 3 captures image information formed by the shadow and the blank on the back of the horizontal curtain 1, the image processing arithmetic device calculates an azimuth angle through the angle information of the shadow of the light shading rod 2, and calculates an elevation angle through the length information of the shadow of the light shading rod 2. The image processing arithmetic device is internally arranged in the singlechip, and the calculation is finished through the singlechip.

The data output interface is connected with the LCD screen and the USB interface.

The measuring process of the device is as follows:

the device is placed on an open and non-blocking horizontal plane, and the north indicator on the horizontal curtain is ensured to point to the north. When the program calculates, this direction is considered to be the 0 ° direction.

An image is acquired. Sunlight irradiates the device, the shading rod casts a shadow on the horizontal curtain, and the rest part of the curtain is relatively bright due to the direct sunlight. The camera below the curtain collects light and shade images on the curtain to obtain digital signals, and the digital signals are input into the single chip microcomputer to be calculated.

The image is analyzed. The single chip microcomputer calculates the azimuth angle and the elevation angle of the sun through a specific algorithm and an image.

And outputting the data. And outputting the result by using an LCD screen and a USB interface. The LCD screen can display the calculation result intuitively, and is convenient for reading out the value immediately, and the USB interface can output the result to a computer or other equipment, so that the computer or other equipment can work together with external equipment.

As shown in fig. 2 and 3, the algorithm for obtaining the position information from the image information:

(1) and (4) importing images. And inputting the image information acquired by the camera module into the singlechip. Since the color information has no meaning in calculating the azimuth and elevation angles, only the gray signal is acquired.

(2) And (5) binarizing the image. And (3) calculating a proper threshold value aiming at the image by using a maximum inter-class variance method, judging the gray value of each point on the image, regarding the pixel points with the gray values smaller than the threshold value as shadows and representing the pixel points as 0, and regarding the pixel points with the gray values larger than the threshold value as bright parts and representing the pixel points as 1. Thus, the image is clearly divided into two parts, shadow and bright.

(3) The shaded portion is found. That is, in the original coordinate system of the picture, the coordinates of all points having a value of 0 are recorded. The positions represented by these coordinates are the shadows.

(4) And (6) calculating the azimuth angle. A straight line is fitted with the coordinates of these points. The shaded portion is elongated and can be roughly viewed as a straight line. The fitting process is equivalent to finding the analytic expression of the straight line. The direction of the straight line is the direction of the shadow, i.e. the direction of the sun. The slope and the inclination angle can be obtained by a linear equation, and the azimuth angle can be further obtained.

(5) And (6) calculating the height angle. The distance between the two points farthest from each other, i.e. the length of the approximate straight line segment, is obtained, and the length of the projection can be obtained according to the specific size of the device. The height angle can be obtained according to the pythagorean theorem and the height of the light shielding rod.

(6) And continuously working. After a certain time interval, the above operations are repeated, and continuous data can be obtained.

Claims

1. A sun position tracking device based on image processing is characterized in that: the device comprises an energy supply device, a sunlight projection device, an image acquisition device, an image processing and operation device and a data output interface; the sunlight projection device comprises a horizontal curtain (1) and a shading rod (2) vertically erected in the center of the horizontal curtain (1), the image acquisition device is a camera module (3) arranged below the horizontal curtain (1), under illumination, the shading rod (2) forms a shadow on the horizontal curtain (1), the camera module (3) captures shadow and image information formed brightly on the back of the horizontal curtain (1), and the image processing arithmetic device obtains a solar azimuth angle and a solar altitude angle through image information calculation.

2. The image processing-based sun position tracking device of claim 1, wherein: the energy supply device supplies power to the photovoltaic power generation device, the piezoelectric energy harvesting device and the external power supply.

3. The image processing-based sun position tracking device of claim 1, wherein: the projection surface of the horizontal curtain (1) is made of transparent white materials.

4. The image processing-based sun position tracking device of claim 1, wherein: the image processing arithmetic device calculates the azimuth angle through the angle information of the shadow of the light shading rod (2), and calculates the altitude angle through the length information of the shadow of the light shading rod (2).

5. The image processing-based sun position tracking device of claim 1, wherein: the data output interface is connected with the LCD screen and the USB interface.