A team led by scientists at the University of California, San Diego has developed a soft and elastic electronic device. When worn on the skin, this device can simulate the pressure or vibration felt on the skin. The latest research has laid the foundation for the development of advanced tactile devices for applications such as virtual reality, medical prosthetics, and wearable technology. The relevant paper was published in the new issue of Science Robotics. The latest device consists of a soft and stretchable electrode connected to a silicone patch. The electrode is made of a new type of polymer material. Polymer materials are composed of two types of polymer building blocks: one is a conductive rigid polymer PEDOT: PSS, and the other is a soft elastic polymer PPEGMEA. By optimizing the proportion of these polymer building blocks, they designed an electrode that is both conductive and stretchable. This device can be attached to fingertips or forearms like stickers, with electrodes in direct contact with the skin connected to an external power source through wires. By sending a gentle current to the skin, it can generate a sense of pressure or vibration based on the frequency of the signal. Researchers explain that existing technologies that reconstruct tactile sensation through electrical stimulation often cause pain due to the use of rigid metal electrodes that are not very close to the skin. To solve these problems, they developed this soft and elastic electrode that can seamlessly fit the skin and provide a wide tactile experience using electrical signals without causing pain to the wearer. In addition, the new device enhances electrode stretchability, ensuring that the current is directed towards specific positions on the skin. In the test, 10 participants wore the device on their forearms. Researchers collaborated with scientists and psychologists from the University of Amsterdam in the Netherlands to determine the minimum detectable current level. Then, they adjusted the frequency of electrical stimulation to allow participants to feel a sense of pressure or vibration. (Lai Xin She)