X-ray CT Boundary Surface Correction Using Spherical Calibration Jig
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The boundary surface of an object is difficult to detect accurately in X-ray CT measurements due to the characteristics of the X-ray source and detector, affecting measurement accuracy.
Innovation Solution
A spherical calibration jig with known dimensions is used in contact with the object to generate volume data, allowing for precise detection of the boundary surface by determining the center coordinates and applying correction values based on profile gradients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional X-ray CT measurement is performed without calibration, then the measurement process is simple, but the boundary surface detection accuracy deteriorates
Solution Approach 1:
A spherical calibration object is introduced as an intermediary between the X-ray CT system and the measurement process. This calibration object with known dimensions serves as a reference standard to detect and correct systematic errors in boundary surface detection, thereby improving measurement precision without requiring modifications to the X-ray CT apparatus itself
Solution Approach 2:
The calibration process is performed preliminarily before actual measurements. By pre-determining correction values using the spherical calibration object, the system establishes a reference framework that compensates for detection errors in subsequent measurements, improving accuracy without adding complexity to the actual measurement workflow
2Measurement precision
If a spherical calibration object is used for correction, then boundary surface detection accuracy is improved, but the measurement process time increases
Solution Approach 1:
The calibration object uses a sphere with known dimensional parameters, transforming the complex problem of boundary surface detection into a simpler parameter matching problem. By comparing detected spherical parameters with known values, correction values are efficiently determined without requiring complex calibration procedures
Solution Approach 2:
The spherical calibration object creates a reference model of expected detection results. By copying the known geometric properties of the sphere into the measurement system as a reference, the system can automatically determine correction values through comparison, reducing the time required for calibration while maintaining high precision
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
This method enhances the precision of X-ray CT measurements without requiring special instruments, enabling high-precision detection of object surfaces.
Implementation Method 1
The X-rays 13 emitted from the X-ray source 12 are transmitted through the object W on the rotating table 16 and reach the X-ray detector 14
Implementation Method 2
The X-ray detector 14 obtains transmission images (projection images) of the object W in all directions
Data Source
AI summary
Volume data is generated by performing a CT scan with a spherical calibration jig having known dimensions in contact with an object. A profile of the surface shape of the object in the volume data is obtained, and a boundary surface of the spherical calibration jig is calculated from the center coordinates of the spherical calibration jig. A correction value for adjusting a boundary surface of the object determined from the gradient of the profile to the boundary surface of the spherical calibration jig is determined, and the boundary surface of the object is corrected by using the correction value. The shape of the object is determined by using the corrected boundary surface. The precision of measurement X-ray CT can thus be increased by accurately detecting the boundary surface of the object.