Point Measurement Without Targets Using Triangulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring points on artifacts, especially those with no distinct features or located in challenging areas like bores, face difficulties in accurately determining the location without target features or optical patterns.
Innovation Solution
A method using predetermined knowledge of the point's location to deduce its position in images, involving the determination of a search line based on the plane containing the perspective centers and nominal location, and identifying where along this line the image meets specific criteria, such as threshold rate of change in contrast or intensity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If target features or optical patterns are placed or projected on the artefact to enable measurement, then the identifiability of points in multiple images is improved, but the complexity of the measurement setup and the practicality for certain artefacts deteriorates
Solution Approach 1:
The invention extracts and removes the requirement for target features or optical patterns from the measurement setup. Instead of adding external markers to the artefact, the method uses the artefact's own geometric information and predetermined knowledge of point locations to enable measurement, thereby simplifying the measurement setup while maintaining measurement precision
Solution Approach 2:
The artefact itself serves as the measurement reference by using its own predetermined geometric information and nominal point locations. The method enables the artefact to self-identify measurement points through image analysis based on expected locations, eliminating the need for external target features and making the artefact self-sufficient for measurement purposes
2Adaptability or versatility
If traditional image matching methods are used without predetermined knowledge, then the method works for artefacts with distinct features, but it fails for points in challenging areas like bores or edges without distinct features
Solution Approach 1:
The invention performs preliminary action by incorporating predetermined knowledge of point locations into the measurement process. Before actual measurement, the system is provided with expected locations of measurement points on the artefact, which are then used to guide the image analysis process and accurately locate points even in challenging areas without distinct visual features
Solution Approach 2:
The invention introduces an intermediary element - the predetermined knowledge of point locations - that mediates between the images and the measurement process. This intermediary information serves as a bridge to accurately identify points in challenging areas where traditional feature-based matching would fail, thereby improving both adaptability and precision
3Measurement precision
If multiple images from different perspectives are obtained to enable triangulation, then the three-dimensional position determination is improved, but the time and complexity of the measurement process increases
Solution Approach 1:
The invention applies partial action by using predetermined knowledge to focus the image analysis on specific regions of interest. Instead of analyzing entire images or performing exhaustive feature matching, the method concentrates computational effort on locating points at predetermined positions, thereby reducing measurement time while maintaining three-dimensional position accuracy through multi-perspective triangulation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables accurate measurement of points on artifacts without the need for target features, improving precision and applicability to areas like small holes, by triangulating the actual location using image perspectives and nominal direction vectors.
Implementation Method 1
obtaining at least two images of an artefact to be inspected from different perspectives
Implementation Method 2
finding said predetermined point in said at least two images... determining the location of said predetermined point in an image comprises determining a search line along which to search within the image
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of measuring at least one point on an artefact to be inspected that is located within a positioning apparatus' measurement volume, the method comprising, obtaining at least two images of the artefact obtained from different perspectives and, based on a given nominal location of a predetermined point to be measured within said positioning apparatus' measurement volume,determine the location of said predetermined point in each of the at least two images.