Angled Laser Line Inspection for Conveyor Shadow Zones
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conveyance systems face challenges in accurately detecting and characterizing objects on conveyor belts, particularly for small, thin, or low-contrast items, due to issues like shadow zones and false detection errors, especially when items have varying heights or shapes.
Innovation Solution
The implementation of an image detecting apparatus combined with an angled laser source to create a diagonal laser line, allowing for the detection of object presence and height by analyzing shifts in the laser line, independent of contrast with the conveyor surface, and enabling three-dimensional representation of items.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional image detection methods are used to detect objects on conveyor belts, then the system is simple to operate, but detection accuracy deteriorates for small, thin, or low-contrast items due to shadow zones and false detection errors
Solution Approach 1:
The patent introduces a laser line as an intermediary element between the light source and the object being detected. The laser line projects a reference pattern onto the conveyor surface, and deviations in this pattern caused by objects provide detection information. This intermediary approach enables accurate detection of small, thin, or low-contrast items without requiring complex multi-camera systems.
Solution Approach 2:
The patent transitions from traditional two-dimensional image analysis to three-dimensional detection by projecting a laser line at an angle to create a diagonal pattern. This diagonal laser line approach adds a height dimension to the detection, allowing the system to detect object presence and characteristics based on laser line displacement rather than relying solely on contrast in the vertical image plane.
2Measurement precision
If angled laser line projection is used to detect object height and presence, then detection accuracy for small and low-contrast items is improved, but device complexity increases due to additional laser source and coordination requirements
Solution Approach 1:
The patent makes the existing camera system multi-functional by having it serve both traditional image detection purposes and laser line analysis purposes. The same camera that captures conventional images is also used to detect deviations in the projected laser line pattern, eliminating the need for separate detection devices and reducing overall system complexity despite the added laser component.
Solution Approach 2:
The patent combines the laser line projection system with the existing image detection apparatus into a unified detection system. The laser line serves as an additional reference layer that is analyzed by the same image processing algorithms, merging height detection capabilities with conventional presence detection without requiring separate processing systems.
3Ease of operation
If vertical camera orientation is used for overhead inspection, then the camera positioning is simple, but shadow zones are created that reduce detection capability for three-dimensional objects
Solution Approach 1:
The patent addresses the shadow zone problem by projecting the laser line at an angle rather than vertically downward. This diagonal projection creates a detection pattern that is sensitive to height variations and can detect objects in areas where vertical lighting would create shadows. The angled laser line approach adds dimensional sensitivity without requiring physical repositioning of the overhead camera.
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 solution effectively detects and determines the presence, position, and height of objects on conveyor belts, including small or low-contrast items, reducing shadow zones and false detection errors, and allows for relocation of objects, while maintaining operational efficiency across different conveyor speeds and item shapes.
Implementation Method 1
an image detecting apparatus positioned directly above and centered above the conveyor with respect to a direction perpendicular to a conveyance path of the conveyor... detecting presence of an item located fully or partially in the zone... based on a characteristic of an angled laser beam detected
Implementation Method 2
determining a physical characteristic or a position of an object, whose presence was detected during the inspection by the camera, based on signals received from the camera regarding one or more breaks in the laser path
Data Source
AI summary
Systems, apparatuses, methods, and computer program products for inspection of objects or items in a conveyance system. Presence (or absence) of an object/item or objects/items is detected sensed and also one or more characteristics of the object/item can be determined based image detection of characteristics of one or more laser lines projected on a conveyance surface of the conveyance system.