CN-122018174-A - All-weather self-adaptive aerial volume imaging and calibrating system and method

CN122018174ACN 122018174 ACN122018174 ACN 122018174ACN-122018174-A

Abstract

The invention provides an all-weather self-adaptive aerial volume imaging and calibrating system and method, comprising a self-adaptive projection subsystem for projecting an imaging beam forming an ideal geometric calibration pattern to an imaging medium area, wherein a feedback monitoring subsystem comprises an unmanned aerial vehicle carrying an optical acquisition device, a lens of the optical acquisition device is provided with a narrowband filter element in front, the passband center wavelength of the narrowband filter element is matched with the light source wavelength of the self-adaptive projection subsystem, a central control unit receives a feedback image acquired by the optical acquisition device in real time and analyzes the distortion deviation of an actual geometric calibration pattern relative to the ideal geometric calibration pattern, and generates an anti-distortion compensation parameter or an adjustment instruction according to the distortion deviation and sends the anti-distortion compensation parameter or the adjustment instruction to the self-adaptive projection subsystem so as to update the projection state of the self-adaptive projection subsystem. According to the invention, a physical calibration plate is replaced by virtual calibration, and strong ambient light interference is restrained by a narrow-band filtering technology, so that stable and accurate imaging of a dynamic medium under a complex atmospheric environment and all-weather conditions is realized.

Inventors

ZHANG XIAOHU
YUAN GUIXIN
CUI JIANNAN
LI JIAYI
XU XIANGPENG

Assignees

中山大学

Dates

Publication Date: 20260512
Application Date: 20260204

Claims (10)

1. An all-weather adaptive aerial volume imaging and calibration system, comprising: The system comprises an imaging medium area, a feedback monitoring subsystem, a central control unit and an adaptive projection subsystem, wherein the adaptive projection subsystem is used for projecting imaging light beams for forming an ideal geometric calibration pattern to the imaging medium area, the adaptive projection subsystem is provided with a dynamic zooming optical module for adjusting a light spot focusing surface in real time according to an imaging distance, the imaging medium area is a space area where the light beams are scattered or excited, the feedback monitoring subsystem comprises at least one unmanned aircraft carrying an optical acquisition device, a narrow-band filter element is arranged in front of a lens of the optical acquisition device, the passband center wavelength of the narrow-band filter element is matched with the light source wavelength of the adaptive projection subsystem and is used for acquiring a feedback image containing an actual geometric calibration pattern, and the central control unit is in communication connection with the adaptive projection subsystem and the feedback monitoring subsystem and is used for receiving the feedback image acquired by the optical acquisition device in real time and analyzing the distortion deviation of the actual geometric calibration pattern relative to the ideal geometric calibration pattern, and generating anti-distortion compensation parameters or adjustment instructions according to the distortion deviation and sending the anti-distortion compensation parameters to the adaptive projection subsystem so as to update the projection state.
2. The all-weather adaptive air volume imaging and calibration system of claim 1, wherein the imaging medium in the imaging medium area is a cloud layer at the bottom of a troposphere, an atmospheric sol layer, or a dry ice smoke curtain wall released by a matched device, and the light beam is diffusely reflected on the surface of the imaging medium to form a pattern, and the adaptive projection subsystem comprises: a monochromatic solid-state laser for generating continuous wave or high frequency pulsed laser light; the beam expanding and collimating lens is used for expanding and collimating the laser output by the monochromatic solid-state laser; the dynamic zooming module is used for dynamically adjusting the beam convergence point in the optical axis direction; A two-dimensional galvanometer scanning system for deflecting the beam in a two-dimensional plane to form a desired geometric calibration pattern; And the F-theta field lens is used for correcting geometric distortion of the scanning field.
3. The all-weather adaptive aerial volume imaging and calibration system of claim 2 wherein the feedback monitoring subsystem is a single frame unmanned aerial vehicle with an optical acquisition device mounted thereon for acquiring as a feedback image an actual geometric calibration pattern of the imaging medium surface reflection.
4. An all-weather adaptive air volume imaging and calibration system according to claim 3, wherein the central control unit is configured to: Processing the feedback image, and extracting edge contour features of the actual geometric calibration pattern; calculating a homography transformation matrix from the adaptive projection subsystem to the surface of the imaging medium based on a preset geometric topology constraint model; singular value decomposition is performed on the homography transformation matrix, the projection angle deviation of the optical axis of the light beam projected to the surface of the imaging medium by the self-adaptive projection subsystem relative to the ideal vertical projection direction is calculated as distortion deviation, And generating an anti-distortion mapping function for driving the adaptive projection subsystem according to the distortion deviation and outputting the anti-distortion mapping function to the adaptive projection subsystem, and adjusting the projection angle of a light beam projected to the surface of an imaging medium by the adaptive projection subsystem so as to form an ideal geometric calibration pattern and realize compensation control.
5. The all-weather adaptive air volume imaging and calibration system of claim 1, wherein the imaging medium in the imaging medium region is air molecules broken down by a high energy density at the focal point of the ultra-short pulse laser, the light beam producing plasmon luminescence by exciting the air molecules to form a pattern of spots, the adaptive projection subsystem comprising: a femtosecond or nanosecond pulse laser for generating ultra-short pulse laser with peak power sufficient to break down air molecules; The 3D dynamic focusing scanning system is used for controlling the space position of the laser focus in the three-dimensional space so that the light spot pattern formed by exciting air molecules to generate plasma luminescence by the light beam is a required geometric calibration pattern.
6. The all-weather adaptive aerial volume imaging and calibration system of claim 5, wherein the feedback monitoring subsystem comprises at least two unmanned aerial vehicles or unmanned aerial vehicles carrying binocular vision systems for capturing as feedback images a pattern of spots formed by plasma lighting from different angles.
7. The all-weather adaptive air volume imaging and calibration system according to claim 6, wherein the central control unit is configured to extract actual three-dimensional coordinates of a light spot formed by plasma luminescence in the feedback image; Calculating a three-dimensional space deviation vector of the light spot based on the theoretical three-dimensional coordinate and the actual three-dimensional coordinate of the light spot, and taking the three-dimensional space deviation vector as distortion deviation; and establishing a space mapping error table based on the three-dimensional space deviation vector of the light spot, correcting the control voltage of the 3D dynamic focusing scanning system, and adjusting the space position of the laser focus in the three-dimensional space so as to enable the light spot pattern formed by exciting air molecules to generate plasma luminescence to be a required geometric calibration pattern.
8. The all-weather adaptive aerial volume imaging and calibration system of any one of claims 1 to 7, wherein the adaptive projection subsystem is deployed on the ground to form a ground-to-air projection array or on an unmanned aerial vehicle to form an air-to-air dynamic projection platform.
9. An all-weather adaptive air volume imaging and calibration method, characterized in that it is implemented based on the all-weather adaptive air volume imaging and calibration system according to any one of claims 1 to 7, comprising the steps of: s1, controlling an adaptive projection subsystem to project an imaging beam for forming a geometric calibration pattern to an imaging medium area; S2, controlling the feedback monitoring subsystem to move to an observation position, and acquiring an image of an actual geometric calibration pattern formed on an imaging medium area by utilizing an optical acquisition device and a narrow-band filter element; S3, the central control unit processes the acquired image, extracts characteristic information of the actual geometric calibration pattern, and calculates distortion deviation of the actual geometric calibration pattern relative to the ideal geometric calibration pattern; And S4, generating an anti-distortion compensation parameter or an adjustment instruction according to the distortion deviation, and sending the anti-distortion compensation parameter or the adjustment instruction to the adaptive projection subsystem so as to update the projection state of the adaptive projection subsystem.
10. The method according to claim 6, wherein in step S1, the geometric calibration pattern comprises a ring, a grid or an array of feature points.

Description

All-weather self-adaptive aerial volume imaging and calibrating system and method Technical Field The invention relates to the technical fields of air display technology, unmanned aerial vehicle application and photoelectric engineering, in particular to an all-weather self-adaptive air volume imaging and calibrating system and method. Background With the rapid development of technologies such as Augmented Reality (AR), large-scale landscape lighting and air performance, huge visual presentation with sky as a medium has become an emerging industrial hotspot. At present, common aerial imaging technologies mainly comprise two types, namely a landmark type light column or pattern formed by irradiating atmospheric aerosol based on a ground high-power laser, and an aerial curtain wall formed by forming and mounting a smoke generator through unmanned aerial vehicle formation and matching with projection to realize image display. However, in practical engineering applications, the above-mentioned techniques still face a series of serious challenges: (1) The existing scheme is mainly a simple fixed ground projection and air passive viewing mode, the active regulation and control capability of dynamic space relation between a light source and an imaging medium is lacking, and particularly a mature air-to-air movement projection scheme is lacking, so that flexible and multi-angle air 3D display is difficult to realize. (2) The air imaging medium such as smoke, cloud layer, aerosol and the like has extremely strong instability, and can drift, diffuse and change shape under the influence of wind power, temperature, humidity and other environmental factors, so that the preset image has serious and time-varying geometric distortion and brightness attenuation. Most of the existing systems are open loop control systems, and cannot sense the state change of the medium in real time and perform dynamic compensation to correct the errors. (3) The all-weather operation difficulty is that the traditional vision calibration system is almost ineffective in the strong light environment in daytime, solar radiation floods the imaging light beam, so that the system cannot be installed and debugged or performed in daytime, and the all-weather application scene is limited. (4) The calibration means is lacking, and the traditional optical calibration depends on a high-precision physical checkerboard calibration plate. At the high altitude of hundreds of meters, a huge physical calibration plate cannot be hung, so that the spatial pose relation among the internal parameters, the external parameters and the dynamic medium of the projection system is difficult to accurately calibrate, and the imaging geometric precision is affected. In view of the foregoing, there is a need for an air volume imaging system that integrates projection, media sensing and feedback correction, does not rely on a physical calibration plate, and adapts to all-weather environments. Disclosure of Invention Aiming at the problems existing in the prior art, the invention provides an all-weather self-adaptive aerial volume imaging and calibrating system and method, which are used for carrying an optical sensing device by using an unmanned aerial vehicle in an unstructured space without a fixed physical screen to perform all-weather geometric calibration, distortion correction and closed-loop control on a volume imaging system based on scattering media such as aerosol, water mist, natural atmosphere or ionized plasma. The invention provides the following technical scheme for realizing the purpose: in one aspect, an all-weather adaptive aerial volume imaging and calibration system is provided, comprising: The system comprises an imaging medium area, a feedback monitoring subsystem, a central control unit and an adaptive projection subsystem, wherein the adaptive projection subsystem is used for projecting imaging light beams for forming an ideal geometric calibration pattern to the imaging medium area, the adaptive projection subsystem is provided with a dynamic zooming optical module for adjusting a light spot focusing surface in real time according to an imaging distance, the imaging medium area is a space area where the light beams are scattered or excited, the feedback monitoring subsystem comprises at least one unmanned aircraft carrying an optical acquisition device, a narrow-band filter element is arranged in front of a lens of the optical acquisition device, the passband center wavelength of the narrow-band filter element is matched with the light source wavelength of the adaptive projection subsystem and is used for acquiring a feedback image containing an actual geometric calibration pattern, and the central control unit is in communication connection with the adaptive projection subsystem and the feedback monitoring subsystem and is used for receiving the feedback image acquired by the optical acquisition device in real time and analyzing the distortion deviat