U.S. Navy Replaces Obsolete Part With 3D Printing
A "scan-to-CAD-to-fab" method fabricated a new cover for the AN/TRC-194 antenna.
When neither the original parts nor the original cast were available to repair the U.S. Air Force’s AN/TRC-194 antenna, experts from Space and Naval Warfare Systems Command (SPAWAR) stepped in with their 3D printing technology.
The azimuth antenna drive, failing because of rainwater intrusion, needed a robust and agile new cover. To develop a solution, SPAWAR Systems Center Pacific’s lab, called RESTORE—Reverse Engineering, Science and Technology for Obsolescence, Repair and Evaluation—paired with the Undersea Communications and Integration Program Office, which falls under the U.S. Navy’s Program Executive Office Command, Control, Communications, Computers and Intelligence (PEO C4I).
Several antenna designs were created and tested within a CAD model developed using a 3D laser scanner. “Scanning the entire system allows us to create a blueprint that our engineers can reference when fabricating a solution,” explains Stephen Cox, the RESTORE Lab’s chief engineer.
A two-piece nested shell design described as “armadillolike” was selected and manufactured on a 3D printer, according to a Navy release. The entire process, from scanning to printing a prototype, took about six months. Cox coined the phrase “scan-to-CAD-to-fab” to characterize the method.
The method “lowers the cost and increases the speed at which a unique product can be made,” Cox explains. “It also facilitates rapid changes, and the product becomes better, faster with each engineering cycle.”
RESTORE is a reverse-engineering laboratory that “uses a process that identifies a target obsolescence issue in a legacy system—usually a single point-of-failure component or assembly—and creates a modern form, fit and function replacement to support life-cycle extension programs,” he says.