A Large-Area Robotic Skin for Intelligent Tactile Interaction of Collaborative Robots

Tactile sensing plays a crucial role when the robot interacts with the environment. In order to detect various potential physical contacts, it is necessary to develop a large-area robotic skin deployed on the entire body to achieve distributed tactile perception. Electrical resistance tomography (ERT) technology has recently been introduced into continuous large-area tactile sensing. Although the ERT-based tactile sensor overcomes some limitations of traditional array-based tactile sensors in large-scale deployment, it still faces some challenges in practical applications. In this article, a large-area ERT-based tactile sensor using a piezoresistive sponge is proposed. Specifically, we fabricate a novel high-sensitivity piezoresistive sponge based on multiwalled carbon nanotubes and polyurethane sponge for pressure sensing. On this basis, combined with ERT technology, a flexible large-area tactile sensor is designed for distributed tactile detection. For the proposed tactile sensor, a data-driven imaging method is proposed to achieve high-quality tactile sensing. Experimental results show that the large-area tactile sensor using this method can achieve good spatial resolution, sensitivity, and positioning accuracy. In addition, in order to further evaluate the performance of the sensor in actual robot tasks, the proposed tactile sensor is integrated with a robot arm, and some tactile interaction experiments are conducted. The experimental results once again verify the effectiveness of the sensor.