The use of printed electronics for sensors has been growing for a variety of reasons. The ability to design a flexible sensor that can be used in hard-to-place environments is one key benefit.
 
Giovanni Nino, director, Composites R&D for Qi2, a $4 billion leader in industrial tool development for a variety of industries, including aviation and energy, described some of his company’s uses of printed electronics and additive manufacturing recently during Printed Electronics USA 2015.
 
“To advance manufacturing, you need to introduce functionality, by fabricating smart things for dumb things,” Nino said. “We want to print functional systems to increase functionality of structures while reducing weight, manufacturing complexity and costs.”
 
Qi2 has printed a wide range of sensors, including health monitoring, flex touch screens, coils and antennas, corrosion sensors and strain gages. The company has successfully developed printed electronic sensors for a range of detection activities, including corrosion testing for the F15 trailing edge wing.
 
“Damage can occur at multiple points on aircraft, usually on zones with difficult or not access at all with drastic consequences,” Nino noted. “Permanent installed sensors can monitor structural health. A way to reduce structural risks is by replacing conventional inspections with permanent installed sensors on the structure.
 
“In the case of the F15 TE wing section, there are some areas inside the wing where the only option to inspect them is by performing an expensive disassembly operation that removes the wing skins,” Nino told the audience. “Qi2 created a flexible circuit for the trailing edge section on the F15 wing to test for corrosion.” He added that the flexible circuit contained four to six layers, and was bonded to the aircraft.
 
Another area where Qi2 has had success is in anti-ice/de-ice protection. Qi2 has developed 3D printed sensors as well as electrothermal heaters for aircraft wings and sensors for helicopter rotor blades.
 
Nino said that the intersection between 3D, PE is ideal for R&D, rapid prototyping and manufacturing applications for UAVs and small aircraft structures, and the possibilities are virtually limitless.
 
“The integration between PE and 3D printing will accelerate design, fabrication and testing of smart systems as well novel flying vehicles,” Nino concluded. “We are combining PE with 3D printing to achieve fully integrated solutions. The levels and sizes of functional features are limited only by the designer’s imagination.”