Abstract:

Flexible tactile sensors have attracted much attention since they can imitate the sensory function of human hand skin, showing a conceivable application in humanoid robot, human-machine interaction and so on. Unfortunately, the practical performance of these sensors is restricted by the drawback of inconvenient-multifunctional response, such as force and temperature-derived bimodal signals with high coupling that need to be decoupled via complex algorithms. Herein, in this study, a novel IL/SWCNTs/PEDOT:PSS nanocomposite film was fabricated and shows the Seebeck coefficient of 29.1 µV·K^-1 and electrical conductivity of 8448 S·m^-1, in which PEDOT:PSS forms a stable flexible matrix, SWCNTs provides a continuous conductive network, and the incorporation of IL plays the dual roles in promoting the dispersion uniformity of SWCNTs and the phase separation of PEDOT:PSS. Further, via the piezoresistive mechanism and thermoelectric output principle, this nanocomposite film derived dual-modal flexible tactile sensor was endowed with the comprehensive feature of pressure and temperature response behaviors without any mutual coupling manner, manifesting the skin-like functions of selective sensing capability. Finally, this flexible device is integrated into a humanoid hand for accurately distinguishing the materials and shapes of objects, demonstrating a recognition accuracy of over 98% via the aid of a machine-learning strategy. It can be believed that this study will inspire the development of next-generation biomimetic robots with tactile perception.