Advanced laser-based dimensional metrology for inprocess automation of rubberized cord production for high performance tires manufacturing

Abstract

Steel and textile cord coating is one of the key rubber processing technologies in tiremaking industry. Specifications are very demanding. In particular, thickness variation across the sheet profile and downstream is very difficult to fulfill. For in-process thickness measurement the most common are systems based on non-contact beta or gamma radiation sensors. Regardless of their wide use, non-contact radiation sensors possess serious drawbacks: they are measuring thickness in indirect way only, they are highly sensitive to variations of material properties, and probably the most critical one, they are potentially dangerous for both, personnel and environment. Recent advances in optoelectronics have founded new alternative method for non-contact thickness measurement based on laser triangulation. Extremely delicate optical properties of fresh calendered rubber end severe environmental conditions create serious problems in implementation of this technology. This paper presents general conceptual framework for in-process laser-based thickness measurement, and proposes a new method for processing acquired sensory data based on statistical surface characterization. Proposed method is experimentally verified, and based on these results the new measuring systems are developed and implemented in industry.