CN110836616A

CN110836616A - Image correction detection method for accurately positioning impact point of laser simulated shooting

Info

Publication number: CN110836616A
Application number: CN201810942836.1A
Authority: CN
Inventors: 曹立军
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-08-17
Filing date: 2018-08-17
Publication date: 2020-02-25
Anticipated expiration: 2038-08-17
Also published as: CN110836616B

Abstract

The invention belongs to the field of military laser simulated shooting training equipment, and particularly relates to a laser simulated shooting training device which integrates a double camera and a target, realizes accurate positioning detection of a laser impact point in laser simulated shooting training, and has the characteristics of simple structure, convenience in use and the like. The standard chest ring target is made into a closed target cavity, the target picture is arranged on the rear plate, the front plate is a transparent organic glass plate, two industrial cameras are obliquely arranged at two corners of the bottom or the upper part in the target cavity, and the optical axes of the cameras penetrate through the target center and are parallel to the target picture. The two industrial cameras shoot the target image and the emitted laser spots, the position coordinates of the target image hit by the laser spots are determined through inquiring the coordinates of the control points and approximation calculation according to the images detected by the cameras and the placement positions and angles of the cameras, and information is wirelessly transmitted to a shooting position display. The method and the device provided by the invention can provide support and help for laser simulated shooting training of troops or national defense education of various schools, and effectively improve the efficiency of the shooting training.

Description

Image correction detection method for accurately positioning impact point of laser simulated shooting

Technical Field

The invention relates to the field of military simulated shooting training equipment, belongs to the method and technical invention, and particularly provides a detection method and a detection device for positioning a shooting impact point with laser simulation precision.

Background

In military shooting training, the precision shooting training of light weapons is the most basic item of shooting training, is the skill that each soldier must master, and is the basic content of military subject training in national defense education of all levels of institutions. Because the requirements of the ball firing training on field conditions are high, and potential safety hazards exist, soldiers adopt a simulated aiming firing training mode in a large quantity. In the simulated shooting training, aiming and firing are mainly carried out in an empty gun mode, and trainees are difficult to know the mastering condition of training skills without knowing the state after firing. The simulated shooting mode of emitting laser can be adopted instead, and the simulated shooting training of the light arms based on the laser is an effective training mode, has the advantages of safety, low cost, low requirement on training fields and the like, and can be widely applied to the simulated shooting training of the light arms. However, the equipment requires good laser focusing performance, no light scattering at a distance of 100 meters, and positioning detection of laser spots is still a key technology and a difficult problem of automatic target reporting of laser simulated shooting, and the actual training requirements are difficult to meet by mainly adopting a manual mode, a photosensitive tube array or a mode of performing camera shooting at a distance from a target surface. The manual mode is that the shooting laser spot hitting position is determined by a person at the far-end target surface and the shooter is informed, so that the efficiency is low and the application is inconvenient; the photosensitive tube array can automatically detect the hitting position of a laser shooting light spot, but the detected target surface is large in size and inconvenient to use, and a large number of photosensitive tubes are adopted on the target surface of 500X500mm to ensure the detection precision, so that the cost is high, the detection circuit is complex, the positioning precision is poor, the equipment is heavy, and the popularization and the application are difficult. In order to ensure the accuracy and undistorted images of the target surface to be detected and the laser spot to be shot, a camera is required to be installed at a distance from the target or at a far-end shooting position, then an image identification method is adopted, the camera needs to be readjusted or fixedly installed and cannot be moved every time the camera is used, the camera is inconvenient to install and use, and the camera is difficult to train and apply in the field. Therefore, the laser simulated shooting training equipment does not have a detection scheme for detecting the position of the target surface hit by a laser spot, which is convenient, practical and high in precision, based on the factors of technology, cost, convenience in use and the like.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a novel detection method and a realization device for accurately positioning laser spots (impact points) in laser simulated shooting training.

The technical scheme adopted by the invention for solving the technical problems is as follows: a laser emitter, a vibration motor and a sound simulator are additionally arranged on a small arms (such as an automatic rifle or a simulation gun), when aiming and firing, laser pulses are emitted, and sound and vibration are simultaneously generated to simulate the firing effect of a real shooting bullet. Laser simulation precision shooting chest ring target is arranged at the far end, a closed cavity is formed as shown in figure 1, the target surface is standard chest ring target paper and is positioned behind the closed cavity. A transparent acrylic plate which is the same as the target paper in size and 1-2 mm in thickness is placed in front of the closed cavity, so that a far-end shooting trainer can clearly see the chest ring target graph through the transparent acrylic plate. The camera is located within the enclosed cavity. The target is made into a closed cavity, mainly considering the dustproof, waterproof and other protective effects of electronic equipment such as a camera and the like under various field application environments, and ensuring the reliable application of the equipment under various environments. Two wide-angle industrial cameras are arranged on the bottom surface (or the upper surface) of the target closed cavity in a 45-degree oblique direction, such as 2 and 3 in the attached drawings. The shooting optical axis of the camera is parallel to the chest ring target, the distance is about 3cm (for convenient use, the thickness of the whole target is designed to be less than or equal to 7 cm), and the centers of the optical axes are respectively adjusted and aligned with the center of the target. Although the shooting of the industrial camera is parallel to the target image, the wide-angle plane lens is adopted, the whole target surface image can be shot in the plane direction of the target image, only the image can generate very large distortion, the barrel-shaped distortion is included, the shooting distance is 0-800 mm, the shooting optical axis and the shot object surface are seriously not perpendicular (which is equivalent to parallel), the deflection angle is very large (approximate 90 degrees), the image can generate serious deformation of nearly large and small size due to perspective, the shot target surface image can generate very large deviation with the actual image, the shape of the target image and the accurate laser spot position can be difficultly identified from the image shot by the camera, and therefore the traditional solution requires that the camera has a certain distance with the target surface so as to eliminate the deflection angle and barrel-shaped distortion.

The invention adopts two industrial cameras which are obliquely arranged, the center line of the optical axis of the camera is adjusted to the center of the detection target image, and a two-dimensional image is shot. After the camera positions are fixed, although the images shot by each camera are greatly deformed, the images are fixed, namely the images with large deformation are collected. In this way, firstly, according to the target surface structure, each camera respectively finds out the deformation coordinates (pixel coordinates) of the plane points of each control equal interval according to the picked deformation image, and establishes the target image deformation coordinate data table of each camera. The purpose of using two industrial cameras is that the distortion of the captured images is very large, i.e. the distortion size is different for each industrial camera in different target surface coordinate positions. 2 images are shot by the two cameras and mutually corrected, so that the detection and positioning precision can be effectively improved.

In practical application, when the shot laser spot hits the target surface, the two cameras can not only shoot the deformed target surface image, but also capture the shot laser spot. At the moment, the captured laser spot is on the deformed target surface image, the laser spot is calculated according to a centroid method, and the central pixel coordinate of the laser spot is determined. And determining the actual position of the spot according to the corresponding table look-up of the target deformation coordinate data table, and determining the actual coordinate value of the spot on the target surface by successive approximation calculation according to the position relation between the central pixel coordinate of the laser spot and the coordinate of the control point in the table.

More critically, such a distorted pattern is difficult to accurately determine the spot position due to the very large off-angle. The invention adopts two cameras to acquire images to obtain the position of a shot laser spot. According to the position of each camera on the target surface and the position of the image shot by the camera, the central pixel coordinates of the laser light spot are respectively determined, and then the middle point of the central pixel coordinates is taken as the actual coordinates of the light spot. By adopting the processing method, the image processing of the two cameras is adopted, which is equivalent to reducing the influence of deflection angle distortion and barrel distortion, so that the obtained measurement result is accurate, and the problems that the original image is difficult to recover from the large distortion figure and the position of the laser spot on the target surface is difficult to determine are solved.

The image processor 5 in the attached drawing 2 is a high-performance computer with strong computing power and high in computing speed, the coordinates of the center pixels of the laser spots of the laser hitting the target surface are determined by resolving the imaging graphs of the industrial camera 1 and the industrial camera 2 and are wirelessly transmitted to the target position computer 6 in the attached drawing 2, the coordinate positions of the actual shooting laser spots on the target surface are displayed through the display 7, and a shooter can know the shooting training condition of the shooter in real time.

The method is characterized in that: the method and the device for realizing accurate positioning of the laser spot (impact point) by utilizing two industrial cameras for redundant measurement and correction processing of large-deformation images in laser simulation shooting are provided, and the problem of accurate positioning of impact point detection in laser simulation shooting in field portable environment application is solved. Two wide-angle industrial cameras are placed at two adjacent angle positions of the target, and the optical axis is parallel to the target surface. The high-performance image processor is adopted to process the large-deformation two-dimensional images shot by the two industrial cameras, so that the detection and positioning precision is ensured. The structure can achieve the purpose that the thickness of the detection target is less than or equal to 10cm, the camera and the detection target are integrated, the integrity is good, the camera is portable, the camera can be installed and retracted randomly, and the camera is convenient to apply under various environments.

The beneficial results of the invention are: provides a convenient and accurate detection method and device for the light spot hit by the target surface in the laser simulation precision shooting training. A transparent acrylic plate with the thickness less than or equal to 2mm is placed in front of a standard chest ring target picture to make a target cavity transparent and closed (mainly dust-proof, waterproof and the like are applied to outdoor environment), two wide-angle industrial cameras are placed at two bottom corners in the closed target cavity, an optical axis is parallel to the target surface, the large-deformation target surface can be shot respectively, and shot laser spots can be captured. When the laser beam penetrates through the acrylic plate and hits the chest ring target image, the image processor corrects and calculates the image distortion according to the target image shot by the two wide-angle industrial cameras and the position of the laser spot, and the position of the laser spot hitting the chest ring target image can be determined, so that the position of the laser spot hitting the target surface during laser simulated shooting training is determined. Compared with the traditional method, the automatic target scoring device solves the problems of heaviness, inconvenience in use and the like of the automatic target scoring device for laser simulated gunnery training, has a simple target structure, is convenient, practical, safe, reliable and high in precision, can greatly improve the efficiency of gunnery training, and provides powerful guarantee for the simulated gunnery training of the army.

Drawings

FIG. 1 is a schematic view of the installation position and target frame structure of two wide-angle industrial cameras according to the present invention;

FIG. 2 is a schematic diagram of the composition of the target detection system of the present invention.

In the drawings, the reference numbers: 1. detecting the laser hitting the target map; 2. a wide-angle industrial camera 1; 3. a wide-angle industrial camera 2; 4. detecting the target frame; 5. an image processor; 6. a shooting position computer; 7. the hand position laser hits the display.

Detailed Description

The invention is further described with reference to the following examples:

the technical implementation of the method is as shown in fig. 1, two wide-angle

industrial cameras

1 and 2 are adopted, the number of pixels is 720P (1280 × 720=92 ten thousand pixels, increasing the number of pixels increases the measurement accuracy, but the amount of processed data increases), the optical axis of the camera is parallel to the target surface, the axis line is adjusted to be aligned to the center of the target surface, and the shooting inclination angle is 90 degrees, which is equivalent to the arrangement shown in the drawing. When the detection size of the target surface of the chest ring is 500X500mm, the diagonal size of the detection target surface of the wide-angle camera is 707mm, the wide-angle pixel is 1280, and the resolution of each pixel is less than or equal to 1mm (due to serious image deformation, the detection precision of different positions can be different). The laser irradiation target surface spot diameter is designed to be less than or equal to 50mm (100 m distance), and the resolution ratio is satisfied. In calculation, the spot center position coordinates are determined first.

Because the image is seriously deformed and the calculation data amount is large, in order to ensure the calculation speed and the calculation precision, the adopted algorithm is the combination of table look-up and successive approximation, the calculation time can be effectively reduced, and the positioning precision is improved. Firstly, according to the position of each camera, an original target surface image is shot, some fixed position control points are set, the corresponding relation between the deformation image positions and the actual positions of the control points is determined, and two data tables are respectively established. Specifically, when the shooting positioning detection is applied, the general actual position is calculated by table lookup according to the central position coordinates (which are pixel coordinates of a deformation image) of the shooting laser facula. And performing approximation calculation according to the relation between the coordinate of the control point in the original table and the coordinate of the control point, and respectively processing the images processed by the two industrial cameras to obtain the minimum error so as to determine the actual coordinate of the light spot center on the target surface. The algorithm combines table look-up calculation and multiple approximation calculation, and has the advantages of high calculation speed, high precision and small error.

Additional description:

1. the standard precision chest ring target area is 500mm, a 1280X720 pixel wide-angle industrial camera is selected according to an example, the shooting distance is 0-800 mm, and the image distortion is serious, including barrel distortion and inclination deformation. Two cameras are adopted for shooting at two angles, images are not required to be restored, only the position of the center point of a light spot is required to be determined, and the influence of deformation of a large inclination angle (approximate 90 degrees) can be effectively eliminated. More than two cameras may further improve the positioning accuracy, but may increase hardware costs and computational complexity.

2. The use of a camera having 1080p or more pixels can further improve the detection accuracy, but increases the computational effort and cost.

3. Because the laser beam is relatively large (the distance to the target surface is set to be less than or equal to 50 mm), the actual wide-angle industrial camera collects more laser beam pixel points, and the position of the central point of the laser beam is determined according to the centroid method.

4. The invention mainly solves the key problem of accurate positioning and detection of impact points in laser simulation precision shooting training. In order to realize the laser simulation precision shooting training, the whole system also comprises laser simulation shooting, detection signal processing, wireless transmission, target position real-time graphic and text display and the like.

Claims

1. A method for locating the impact point of laser simulative shooting training in different environments includes such steps as installing industrial cameras in target, collecting image information, and determining the position of laser spot on target map, and features that after the laser beam hits the target map by transparent organic glass, two industrial cameras are used to detect the image shot by the camera, the optical axis of camera is parallel to the target map and regulated to the center of target map, and the two industrial cameras are used to shoot the target map and laser spot image.

2. The method of claim 1, wherein the two industrial cameras can be placed at other corner or edge positions within the target cavity.