News | Nov 14, 2019

Navy engineer 3D prints ‘smart parts’ with built-in sensors, strain gauges

News Article Image of Navy engineer 3D prints ‘smart parts’ with built-in sensors, strain gauges

Stephen Cox, a chief engineer at Naval Information Warfare Center–Pacific, uses a laser scanner while working in the Reverse Engineering–Science and Technology for Obsolescence, Restoration and Evaluation Lab.

Alan Antczak/Navy

An engineer leveraging the capabilities of 3D printing to enhance maintenance aboard U.S. Navy ships has invented a new way to let tools, structures, or machines tell us when they’re stressed out.

Stephen Cox, a chief engineer at the Naval Information Warfare Center–Pacific in California, came up with the idea for “smart parts,” which was first made public on Thursday in a pair of U.S. patent applications (linked below).

Cox’s idea is to use conductive inks to create strain gauges and temperature sensors within 3D printed structures like pressurized fuel tanks, hand tools, or mechanical linkages. The embedded sensors are connected to passive RFID tags, which allow the sensors to communicate their data wirelessly, allowing users to test, monitor, repair, or replace the equipment.

An illustration of a mechanical linkage that was 3D printed to include a “smart part” strain gauge sensor that can be monitored wirelessly.

The patent application includes other uses:

  • The smart part solves the part-qualification and file-security problem that has plagued the field of additive manufacturing parts.
  • The smart part also is capable of providing real-time information regarding the performance of the part, which information would provide options to an operator to, for example, run a machine hard, knowing that failure is imminent to complete a critical goal.
  • Another option enabled by the smart part includes idling a machine while maintaining minimum capability until a repair or replacement is available.
  • Another option enabled by information from the smart part includes justifying shut down or replacement of a machine.
  • The smart part also enables real-time statistical process control; knowing exactly when the smart part will go off-line, what is wrong, the cost of the repair, and time to repair and restore.

In some applications, Cox has also invented a quality assurance test by printing a flexible diaphragm into the smart parts that can be depressed and audibly “pops” back.

Through technology transfer, private businesses can leverage the U.S. military’s research and development work to integrate this and other military inventions into their own products and services.

A patent license agreement with the Navy would allow U.S. companies to integrate the smart parts technology into their products sold in military or commercial markets. A cooperative research and development agreement may also be appropriate to further the technical readiness level.

Dr. Brian Metzger, senior technology manager at TechLink, is an expert in invention licensing and is assisting the Navy with its technology transfer efforts.

Metzger has already begun working with Cox on helping companies license another technology he invented that involves LiDAR imaging.

Metzger also said he’s been briefed on related work at the Air Force Research Laboratory, where Dr. Emily Heckman, a senior electronics engineer, has invented a way to fabricate strain gauges directly on 3D printed substrates.

“Commercial strain gauge technology has limitations including surface prep, special adhesives that can delaminate, et cetera,” Metzger said. “There are clear applications for this in DOD and non-military fabrication that make the patents valuable.”

Businesses interested in evaluating Navy inventions for commercialization can contact Dr. Brian Metzger at or 406-994-7782.