Web Defect Marking Using Fiducial Tracking After Slitting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing automated inspection systems for moving webs face challenges in accurately identifying and marking defects, especially in wide webs with small defects, and when the web is slit into smaller rolls, leading to inefficiencies in material utilization and rapid product changeovers required by 'just-in-time' manufacturing.
Innovation Solution
A system that separates the identification of anomalous regions from the web at one location and time, and the localization and marking of defects at another, using imaging, digital processing, fiducial marks, and subsequent algorithms to determine and mark only actual defects relevant to the intended end-use, allowing for deferred marking and reduced material waste.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If edge marking is used to identify defective regions, then the marking process is simple and quick, but the defect cannot be accurately located when the web is slit into smaller rolls or when defects are small and wide
Solution Approach 1:
The system divides the web into segments by placing fiducial marks at regular intervals, then independently tracks and marks defects within each segment. This segmentation allows accurate defect localization even when the web is slit into smaller rolls, as each segment maintains its defect information separately.
Solution Approach 2:
Fiducial marks serve as intermediary reference points between the inspection system and the marking system. These marks enable precise correlation between detected defects and their physical locations on the web, allowing accurate marking even after the web undergoes processing or slitting operations.
2Reliability
If all anomalies are marked immediately upon inspection, then defect identification is comprehensive, but material waste increases because defects relevant to specific end-uses are not distinguished
Solution Approach 1:
The system dynamically adjusts marking decisions based on end-use criteria. Instead of statically marking all anomalies, the system allows users to specify different defect thresholds for different end-uses, and only marks anomalies that exceed the relevant threshold for the intended application, thereby reducing unnecessary material waste.
Solution Approach 2:
The system changes the parameter of defect severity thresholds based on the specified end-use. By allowing users to input different quality requirements for different applications, the system adapts its marking behavior to match the actual needs, marking only those defects that would genuinely impact the specific end-use.
3Productivity
If inspection and marking are performed at the same location and time, then the process is efficient, but the system cannot adapt to different end-uses that may be determined later
Solution Approach 1:
The system performs preliminary inspection and records all anomalies with their precise locations relative to fiducial marks, but delays the final marking decision. This allows end-use criteria to be determined later without requiring re-inspection, as all defect information is already captured and stored for subsequent marking operations.
Solution Approach 2:
The system extracts and stores defect information separately from the marking action. By recording anomaly locations, types, and characteristics in a database associated with fiducial mark positions, the system decouples inspection from marking, enabling flexible adaptation to different end-uses while maintaining complete defect records.
Data Source
AI summary
A system for the characterization of webs that permits the identification of anomalous regions on the web to be performed at a first time and place, and permits the localization and marking of actual defects to be performed at a second time and place.