Diagnosis of Defects in Paper Manufacture

Exsys Corvid Demo

Flaws and holes in the paper making process can very quickly turn into a catastrophic situation. If they are not identified quickly they can cause damage as extensive as having the roll tear and having to shut down equipment. This can be very costly due to delays or damaged equipment, staff overtime and frustration, and it can cause a rescheduling and product fulfillment nightmare. These types of problems must be identified promptly.

This system was developed at a large paper manufacturing plant. It will diagnose the causes of various types of holes in the paper being produced. The system asks a variety of questions on the type and location of the hole, and about machine characteristics that can be easily seen by the operator. The system will present a list of the most likely sources of the problem that is producing the defective paper, arranged in order of likelihood.

This type of diagnostic problem is particularly complex because a diagnosis is probabilistic and based on considering many individual factors collectively. The diagnostic logic can not be diagrammed as a tree where the user works their way out to the end of a branch with the diagnosis. Instead many rules are used to rank and combine various factors that are each indicative of particular causes for the defect, to produce a list of the most likely causes. Being able to deliver this type of deep knowledge based on extensive experience with the machinery is particularly valuable. It is the type of knowledge that is difficult to teach and requires years of experience. The Exsys Corvid rule based expert system is ideally suited to this type of problem.

This system contains actual knowledge of the paper making machine, and many of the questions require some knowledge of the machine to answer in ways that are realistic. Answering in a "random" way can easily produce combinations of input that would not occur in the real-world may not produce any recommendation. When realistic input is provided, the system will do an excellent job in diagnosing the cause for the problem.

For more information on using Exsys Corvid for diagnostic expert systems, click here