Engineering breakthrough: “It could be the branching off point for an entirely new field of designs with exciting applications we haven’t dreamed of yet.”
Future communication network technologies, such as 6G, rely heavily on reconfigurable antennas, which may remotely adjust features such as frequency or radiation beams.
But many of the current designs for reconfigurable antennas have problems: they don’t work well at high or low temperatures, have limited power, or need to be serviced often.
To get around these problems, electrical engineers at Penn State College of Engineering combined electromagnets with a “compliant mechanism,” which is the same mechanical engineering idea behind binder clips or a bow and arrow.
They released the proof-of-concept version of their reconfigurable compliance mechanism-enabled patch antenna in Nature Communications today.
According to Galestan Mackertich-Sengerdy, who serves as a doctoral student and researcher at the School of Electrical Engineering and Computer Science in the college, compliant mechanisms are a unique type of engineering design. Unlike traditional rigid body mechanisms, which rely on hinges for motion, compliant mechanisms utilize the properties of the materials themselves to produce movement when force is applied. These compliant mechanism-enabled objects are specifically designed to bend repeatedly in a predetermined direction and to withstand harsh conditions.
When this method is used on a reconfigurable antenna, its arms bend in a predictable way because of a complaint mechanism. This changes the antenna’s operating frequencies without the use of hinges or bearings.
“Just like a chameleon triggers the tiny bumps on its skin to move,”adds co-author Sawyer Campbell, “which changes its color, a reconfigurable antenna can change its frequency from low to high and back, just by configuring its mechanical properties, enabled by the compliant mechanism.”
The compliant mechanism-enabled designs surpass the existing origami design technologies, named after the Japanese art of paper folding. While origami designs are reconfigurable, they do not possess the same level of robustness, long-term reliability, and high-power handling capabilities as the compliant mechanism designs.
According to Mackertich-Sengerdy, origami antenna designs are celebrated for their ability to fold and store compactly, ready for deployment in an application. However, when these origami folded structures are deployed, they often require a complex stiffening structure to prevent warping or bending. If not designed properly, these devices may face environmental and operational limitations that shorten their lifespan when used in the field.
Using industry-standard electromagnetic modeling tools, the team visualized and created a prototype of a circular, iris-shaped patch antenna.
Then, in the anechoic laboratory at Penn State, a room lined with electromagnetic wave-absorbing material that prevents signals from interfering with antenna testing, they used a 3D printer to create it and tested it for fatigue failures as well as frequency and radiation pattern fidelity.
Researchers say that the technology can be scaled up to the level of an integrated circuit for higher frequencies or made bigger for lower frequency applications. The prototype, which was made to demonstrate a specific frequency, is only slightly bigger than a human palm.
Researchers say that the rise of 3D printing has made compliant mechanism research more popular because it makes it possible to make an infinite number of different designs. Mackertich-experience Sengerdy’s in mechanical engineering gave him the idea to use this type of flexible mechanisms in electromagnetics.
“The paper introduces compliant mechanisms as a new design paradigm for the entire electromagnetics community, and we anticipate it growing,” adds co-author Douglas Werner. “It could be the branching off point for an entirely new field of designs with exciting applications we haven’t dreamed of yet.”
Source: 10.1038/s41467-023-36143-6
Image Credit: Jeff Xu/Penn State