William Edward Wolf

On-line Inspection For Nonwoven Fabrics

An automatic inspector and product data system was developed by Du Pont specifically for the needs of nonwoven fabrics. The system detects defects, classifies them into five categories at high web speeds, and generates roll logs and 24-hour production summaries to assist in production record keeping and improved product flow through the finishing area. Techniques based on multiple feature-extraction and pattern-classification theory permit detection and classification of defects in the presence of product noise.

Inspection and sorting of particulate materials with low optical loss characteristics

Many commercial materials sold in bulk form occur as particulates or pellets at some intermediate stage in their production. Detection of defects and foreign particles at this stage is a useful quality control function. This paper describes a concept and implementation for measuring contaminant count and removing undesirable material from a product stream. The system in its present form is restricted to materials that exhibit low optical loss. Many polymers and other particulates fall into this category or are sufficiently close that the system functions effectively. An optical scanner and material transport system are integrated with a computer system to perform the detection and sorting functions. Throughputs of 60 lbs/hour have been demonstrated and higher rates are possible.

Laser Scanning Techniques For Automatic Inspection Of Heat-Sealed Film Packages

Many products in the food and drug industry are sold in heat-sealed translucent film packages. Automatic inspection of these packages before shipment to the customer is an important step in assuring quality. This paper describes a laser scanner and associated electro-optical and electronic system for inspecting blister packages which also serve as reaction vessels, identifying and classifying defects for process control in an on-line situation. This system is a practical application of a coherent light scanner which utilizes spatial filtering and a transform plane array of optical sensors for performing some of the signal processing necessary for defect detection and classification. Automatic registration in 2 dimensions is incorporated, thus relaxing the positional accuracy requirements of the product handling system.