Method and system for in-process monitoring of a compaction roller of a composite layup machine

A method for in-process monitoring of a compaction roller of a composite layup machine, the method comprising the steps of:

• directing one or more infrared cameras at a back side of the compaction roller of a composite laying head of the composite layup machine, wherein the one or more infrared cameras are mounted aft of the compaction roller, and the one or more infrared cameras have a field of view of a back side portion of the back side of the compaction roller;
• applying heat to a substrate by a heater, wherein the heater is mounted forward of the compaction roller;
• monitoring the back side of the compaction roller, by using the one or more infrared cameras, to obtain one or more infrared images of the back side of the compaction roller, during laying down of one or more composite tows of a composite layup onto the substrate by the compaction roller, the one or more infrared images comprising thermal imprints of the one or more composite tows that the compaction roller has made contact with at a point of compaction, to allow for a temperature change or a thermal change in the one or more composite tows to be imprinted on the back side portion of the back side of the compaction roller;
• identifying, based on the one or more infrared images, one or more temperature profiles of the back side portion of the compaction roller, to obtain one or more identified temperature profiles, wherein the one or more composite tows are in contact with the compaction roller;
• and
• analyzing the one or more identified temperature profiles, to determine a layup quality of the composite layup.

A system for in-process monitoring of a compaction roller of a composite layup machine, the system comprising:

• the composite layup machine comprising:
• (i) a composite laying head with the compaction roller coupled to the composite laying head;
• (ii) a heater mounted forward of the compaction roller, the heater configured to apply heat to a substrate;
• and
• (iii) one or more infrared cameras, mounted aft of the compaction roller, to monitor a back side of the compaction roller, wherein the one or more infrared cameras are configured to each capture one or more infrared images of the compaction roller, during laying down of one or more composite tows of a composite layup onto the substrate by the compaction roller, and the one or more infrared cameras having a field of view of a back side portion of the back side of the compaction roller, and the one or more infrared images comprising thermal imprints of the one or more composite tows that the compaction roller has made contact with at a point of compaction, to allow for a temperature change or a thermal change in the one or more composite tows to be imprinted on the back side portion of the back side of the compaction roller;
• a control system configured to control the composite layup machine;
• and
• a computer system having a composite analyzer, the composite analyzer configured to identify, based on the one or more infrared images, one or more temperature profiles of the compaction roller, to obtain one or more identified temperature profiles, and to enable analyzing the one or more identified temperature profiles, to determine a layup quality of the composite layup, and to determine at least one layup condition of the composite layup, the layup condition comprising a layup defect comprising a tow twist, a misaligned tow end, a missing tow, a tow fold, a fuzzball, a gap, or an overlap.