Measurement/control of sheet material using at least one sensor array

A method for measuring at least one physical property of sheet material comprising the steps of:

• receiving electromagnetic radiation representative of said sheet material therefrom at a location substantially adjacent to initial processing of said sheet material;
• generating a signal representing said electromagnetic radiation received from said sheet material;
• converting said signal into digital signals having magnitudes representing the intensity of electromagnetic radiation received from corresponding points on said sheet material;
• addressing a reference memory in synchronism with said corresponding points on said sheet material to access point specific information for said corresponding points;
• and
• addressing a lookup table with said digital signals and said point specific information to retrieve physical property information for said sheet material corresponding to said digital signals from said lookup table.

A system for controlling a machine making a product in the form of a moving web of sheet material, said control system comprising:

• a first stationary web sensor extending across the entire width of said web of sheet material for monitoring individual elements which extend continuously across the entire width of said web of sheet material and generating first web signals representative of said individual elements of said web of sheet material;
• a second stationary web sensor for measuring a given characteristic of said web of sheet material and generating second web signals representative of said web of sheet material;
• and
• a controller responsive to said first and second web signals for controlling said machine to maintain uniformity and an absolute value of said given characteristic in said web of sheet material.

A method for controlling a machine making a product in the form of a web of sheet material, said method comprising the steps of:

• initializing said machine to produce a web of sheet material having known characteristics satisfying requirements of a given product produced by said machine;
• monitoring said web of sheet material at a location substantially adjacent to initial processing of said web of sheet material;
• controlling said machine in response to said web signals to establish uniformity in said web of sheet material regardless of the absolute requirements of said given product;
• monitoring said product at a location substantially adjacent to final processing of said web of sheet material to generate product signals representative of the weight of said product by performing the step of measuring the weight of a reel accumulating said product;
• and
• controlling said machine in response to said product signals to further control the absolute requirements of said given product.

A method for controlling at least one physical property of sheet material as said sheet material is being manufactured comprising the steps of:

• positioning a first stationary sheet material sensor at a first location along said sheet material substantially adjacent to initial processing of said sheet material;
• operating said first stationary sheet material sensor to generate first sensor signals representative of at least a first characteristic of discrete elements of said sheet material at said first location;
• converting said first sensor signals into first digital signals having magnitudes representing said at least first characteristic of said discrete elements of said sheet material at said first location;
• addressing a reference memory in synchronism with said discrete elements of said sheet material to access element specific information for said discrete elements;
• addressing a lookup table with said first digital signals and said element specific information to retrieve from said lookup table physical property information for the sheet material corresponding to said first sensor signals;
• and
• controlling the manufacture of said sheet material in response to said physical property information to maintain uniformity of said at least one physical property of said sheet material.

A system for controlling a machine making a product in the form of a moving web of sheet material, said control system comprising:

• a first stationary web sensor extending across the entire width of said web of sheet material for receiving light therefrom and generating first web signals representative of said web of sheet material;
• a second stationary web sensor for measuring a given characteristic of said web of sheet material and generating second web signals representative of said web of sheet material;
• and
• a controller responsive to said first and second web signals for controlling said machine to maintain uniformity and an absolute value of said given characteristic in said web of sheet material.

A method for controlling a machine making a product in the form of a web of sheet material, said method comprising the steps of:

• initializing said machine to produce a web of sheet material having known characteristics satisfying requirements of a given product produced by said machine;
• receiving light representative of said product from said web of sheet material at a location substantially adjacent to initial processing of said web of sheet material;
• generating web signals in response to said light received from said web of sheet material;
• controlling said machine in response to said web signals to establish uniformity in said web of sheet material regardless of the absolute requirements of said given product;
• monitoring said product at a location substantially adjacent to final processing of said web of sheet material to generate product signals representative of the weight of said product by performing the step of measuring the weight of a reel accumulating said product;
• and
• controlling said machine in response to said product signals to further control the absolute requirements of said given product.