Monocular Videogrammetry for Dynamic Platform Displacement Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Challenges in achieving uniform illumination and accurate displacement measurements on dynamic platforms due to non-uniform illumination, overexposure, and camera motion, which degrade imaging quality and compromise geometric center estimation.
Innovation Solution
Adaptive local contrast adjustment and wide-baseline dynamic calibration are employed to enhance illumination uniformity and camera pose calibration, followed by 3D structural reconstruction for precise displacement data derivation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If fill lights are used to illuminate artificial target points, then illumination is provided, but uniform illumination is not achieved and imaging quality degrades
Solution Approach 1:
The patent applies local quality by dividing the image into multiple image blocks and processing each block independently with adaptive brightness compensation. Different regions of the image receive customized illumination adjustment based on their specific lighting conditions, rather than applying uniform illumination across the entire field of view. This resolves the contradiction by providing localized illumination quality improvement while maintaining overall measurement precision.
Solution Approach 2:
The patent segments the image into multiple image blocks and processes each block separately through adaptive brightness compensation. This segmentation allows different regions with different illumination conditions to be handled independently, preventing the degradation of imaging quality in any single region while maintaining overall illumination coverage.
2Productivity
If the camera moves to track dynamic platform, then dynamic monitoring is enabled, but spurious components are introduced in measured target displacement
Solution Approach 1:
The patent implements feedback through camera pose calibration using control points with known positions. The system continuously monitors and adjusts for camera motion by calculating pose parameters from control points and using these to compensate for spurious displacement components. This feedback mechanism enables dynamic monitoring while maintaining displacement measurement precision.
Solution Approach 2:
The patent introduces control points as intermediaries between the camera and the measurement targets. These control points with known positions serve as reference markers that mediate the relationship between camera motion and target displacement measurement, allowing the system to separate true target motion from camera-induced artifacts.
3Measurement precision
If precise camera pose calibration is performed for each frame, then displacement accuracy is improved, but computational complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-calibrating control points with known positions before the dynamic measurement process. This preliminary calibration establishes reference data that simplifies subsequent frame-by-frame pose calculations, reducing the computational complexity of real-time calibration while maintaining precision.
Solution Approach 2:
The patent uses control points with known positions as copies or references of the actual measurement targets. These reference control points enable the system to calculate camera pose without requiring complex calibration procedures for every frame, thereby reducing computational complexity while maintaining measurement accuracy.
Data Source
AI summary
A monocular high-speed videogrammetry method based on a dynamic platform includes the following steps: collecting a monocular high-frame-rate image sequence of the dynamic platform and performing preprocessing; conducting dynamic image-block data processing on the image sequence based on adaptive brightness compensation and least-squares fitting (LSF) to obtain adjusted images; performing camera-pose calibration on the adjusted images based on sliding-window constraints to obtain calibrated images; and acquiring three-dimensional (3D) coordinates and estimated displacements of tracking points from the calibrated images, and outputting measurement results based on the 3D coordinates and the estimated displacements. Through optimization of the measurement process, the method supports real-time adaptive compensation, dynamic image-block processing, and camera-pose calibration, thereby providing significant application value. Correspondingly, the present disclosure also provides a monocular high-speed videogrammetry system based on a dynamic platform, which includes modules configured to implement the above steps.