Engineers love a challenge, especially when they can conjure unique solutions. Researchers from the Penn State Department of Engineering Science and Mechanics leading an international team have developed a novel means to power wearables. Led by PSU Professor Larry Cheng, the scientists convert radio waves into electricity using a flexible patch. The researchers recently published their method in Materials Today Physics.The Penn State technology is reminiscent of but different from Georgia Tech’s 5G wireless network energy harvesting, The Penn State group developed the radio wave energy harvester to power the team’s sensor modules. The PSU team designed a stretchable wideband dipole antenna system to transmit data from sensors. This means that it can harvest energy from a range of radio frequencies from the surrounding environment. The engineers integrated the stretchable metal antennas into conductive graphene. The flexible system connects to a stretchable rectifying circuit that converts the radio waves into electricity. The system produces relatively small amounts of electricity, according to Cheng, but because it runs continuously the system can generate sufficient power for the sensor modules.Next steps for the PSU-led group include miniaturizing the circuits and improving the rectifier’s stretchability. Cheng believes the team’s earlier sensor modules can be retro-fitted with the radio wave energy harvesters. The group also intends to explore other applications that could benefit from energy-harvesting technology.