Antennas play a crucial role in wireless communications, navigation, radar, and scientific research, typically functioning as rigid and inflexible structures. However, a groundbreaking initiative by researchers at the Johns Hopkins Applied Physics Laboratory (APL) aims to revolutionize this concept. Since 2019, the project has focused on developing 3D printed antennas made from shape-memory alloys that can deform according to temperature changes. These innovative antennas hold promise for military and space research applications.
This new type of antenna is designed to adapt dynamically to a variety of radio frequencies, offering greater flexibility than traditional antennas. Jennifer Hollenbeck, the project lead, drew inspiration from the science fiction series The Expanse, which features organic technology capable of changing shape. "I have spent my career working with antennas and wrestling with the constraints imposed by their fixed shape. I knew APL had the expertise to create something different,” Hollenbeck remarked.
The antenna is constructed from Nitinol, an alloy of nickel and titanium known for its shape-memory properties, allowing it to return to its original form after being deformed by heat. However, 3D printing this alloy posed challenges, particularly in maintaining the integrity of complex designs during fabrication. Hollenbeck noted, “It turned out to be a really complicated design, and it didn’t work as well as I would have liked.”
Through persistent experimentation and optimization, the team successfully created a planar spiral antenna that transforms into a conical shape upon heating. They also developed a new conductor to heat the antenna effectively, without compromising performance. “We have a lot of experience optimizing processing parameters and designs for alloys, but this was a step beyond,” stated additive manufacturing engineer Samuel Gonzalez. He further explained the trials of working with the material: “We made shrapnel in the printer a few times because the antenna is trying to change shape as you’re printing it, due to the heat.”
The flexible antenna holds significant potential for military applications, enabling more dynamic communication in combat situations. It is also anticipated that the antenna’s adaptability will enhance telecommunications and industrial operations, allowing for seamless switching between short-range and long-range communication modes. Furthermore, it could serve as an adaptable solution for future space exploration missions.
To learn more about this innovative technology, you can find additional details here.