The composites industry will benefit as manufacturing robots become more intelligent, flexible and versatile.
Aerospace and automotive companies appreciate the strength and light weight of composite parts, but currently use them only in relatively limited ways. One reason is because composite part producers can’t currently deliver enough product at the speed and quantities required for large-scale production. But the increasing use of automation and robotics in composites manufacturing could remove those obstacles.
Composites manufacturers began experimenting with robotics for both thermoset and thermoplastic production about 30 years ago, with companies concentrating their efforts on automated tape laying (ATL) and automated fiber placement (AFP). Manufacturers gradually overcame the initial hurdles – the need to develop a targeted heat source for structure consolidation, software and materials suitable for testing – and today many use AFP and ATL to make parts. But limitations remain. The throughput rate is relatively slow, and AFP is restricted by the type and shape of structures it can produce.
The recent introduction of lasers as a heat source is helping to speed production, especially with thermoplastics, according to Ralph Marcario, vice president of sales and marketing for Automated Dynamics, a supplier of automation equipment. With laser heating systems, manufacturers can make products about four or five times faster without sacrificing any quality of consolidation, he says.
“In the automotive model, where generally there’s going to be some kind of secondary operation such as thermoforming or stamping and they don’t need to worry about consolidating on the fly, a laser heat source will enable extremely fast lay-up of preforms,” says Marcario. “That has garnered some particular interest lately from the automotive community, where high-volume production has historically ruled out AFP.”
But automotive and aerospace manufacturers are now most interested in automated inspection. “Although AFP has found more widespread use in production environments, one of the factors that limits its use is the need to still manually inspect the quality of the lay-up between every ply,” says Marcario. He adds that AFP machines actively perform lay-up only 25 to 35 percent of the time a tool is in the machine. The balance of cycle time is spent inspecting the lay-up, reworking tapes as needed, resupplying material and performing both scheduled and unscheduled maintenance. “Usually manual ply inspection takes the most time, often exceeding the machine lay-up time,” says Marcario.