An ionic pressure sensor array with digitizable sensitivity

Abstract Flexible pressure sensors play an indispensable role in electronic skin. A flexible pressure sensor array with a larger sensing area is an inevitable trend for further developing a single flexible pressure sensor. However, pressure sensor arrays suffer from a key challenge: each sensing unit in the array cannot be individually defined for its pressure sensing range and sensitivity. Here, we present an ionic pressure sensor array with digitizable sensitivity achieved through the synergistic cooperation of an ion gel shell interfacial capacitive sensing mechanism and a filler with digitally tunable mechanical stiffness. Through this design, the sensitivity of each sensing pixel unit in the array can be digitally defined in the range of 20 times, and the fabrication process is greatly simplified. We fabricated sensor arrays for object contour recognition and weight judgment, demonstrating their potential application in electronic skin. In addition, we proposed using a customized 3D printer of elastomer to simplify its fabrication process, which is beneficial for engineering applications.