Existing electronic skins reduce sensing accuracy as the material stretches. Researchers at the University of Texas at Austin have developed a new type of stretchable electronic skin that addresses one of the main challenges of this emerging technology. The electronic skin is flexible, providing robots and other devices with human skin-like softness and touch sensitivity, helping them perform tasks that require extreme precision and control. The research paper is published in the latest issue of the journal Matter.
The researchers say the e-skin can stretch and bend like human skin to accommodate people’s movements. The pressure response of the newly developed e-skin remains constant no matter how far it is stretched. This is a major achievement of the technology.
Electronic skin technology can sense the pressure from contact and let connected machines know how much force to use, for example when gripping a cup or making contact with a person. However, when conventional e-skin is stretched, the readings are affected and create errors that affect the sensor’s ability to sense pressure, which can lead to robots exerting too much force.
The key to this research is an innovative hybrid response pressure sensor. While traditional e-skins are either capacitive or resistive, hybrid response e-skins use both pressure responses. The researchers perfected these sensors and combined them with stretchable insulating and electrode materials to innovate e-skin.
In the demonstration, the researchers used the stretchability of the e-skin to build inflatable probes and grippers that could change shape and perform a variety of sensitive, touch-based tasks. For example, a probe wrapped in inflatable skin can accurately capture the body’s pulse waves, and a deflated gripper can securely hold a tumbler without falling. The device can also be pressed with the right amount of force on a crispy taco without crushing it.
The stretchable electronic skin is expected to be a key component of a robotic hand that can be as soft and sensitive as a human hand, the researchers said. It could be used in healthcare, where, for example, a robot equipped with the skin could check a patient’s pulse, wipe a patient’s body, or perform a body massage. It could also be used in disaster relief, allowing such robots to search for the injured and trapped at the scene of disasters such as earthquakes or building collapses.
