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Bionic electronic skin with human sensory capabilities has attracted extensive research interest, which has been applied in the fields of medical health diagnosis, wearable electronics, human–computer interaction, and bionic prosthetics. Electronic skin tactile pressure sensing required high sensitivity, good resolution and fast response for sensing different pressure stimuli. In particular, there were still great challenges in the detection of wide pressure and the preparation of sensitive unit microstructures. Here, the direct-write printing of Weissenberg principle to fabricate GNPs/MWCNT filled conductive composite flexible pressure sensors on PDMS substrates was proposed. The effects of platform moving speed, microneedle rotation speed and the number of direct-write times on the line width of the pressure sensitive structure were investigated based on orthogonal experiments, and the optimal direct-write printing parameters were obtained. The performance of the S-shaped polyline pressure sensor was tested, in which the sensitivity could reached 0.164 kPa−1, and the response/recovery time was 100 ms and 100 ms respectively. The capture cases of objects of different quality and objects with flat/curved surfaces were successively demonstrated to exhibit its excellent sensitivity, stability and fast response performance. This work may paved the road for future integration of high-performance electronic skin in smart robotics and prosthetic solutions.

Tactile sensors with high flexibility have attracted great interest because of their huge potential in various applications including smart robots, smart prostheses, human-machine interfaces, and biological monitoring electronic devices. However, it remains a critical challenge to develop tactile sensors with both high sensitivity and flexibility. In this work, a flexible 8 × 8 array pressure sensors with GNPs/MWCNT filled conductive composite material on PDMS substrates was proposed using direct-write printing. The printing technology based on the Weissenberg effect had the advantages of rapid supply of fluid and avoiding needle clogging in the printing process, which was suitable for large-area manufacturing of sensor sensitive units. The sensitivity of PDMS-based flexible array pressure sensors in the pressure range of 0–25 kPa and 25–75 kPa reached ∼5.09 MPa−1 and ∼0.0209 kPa−1, respectively. Response/recovery time reached ∼150 ms and ∼200 ms, respectively. When 1000 cycles were performed in the 0–75 kPa pressure range, the PDMS substrate flexible array pressure sensor had high stability and repeatability. These superior properties are indicative of their great potential in applications such as intelligent robotics, artificial palpation, prosthetics, and wearable devices.