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• The sensor achieves favorable trade-off between sensitivity (S max > 450 kPa−1) and sensing range (250 kPa). • The sensor shows an excellent self-cleaning attribute. • Flexible circuit board was successfully integrated with the sensor to transmit the force signal. A wearable integrated tactile sensory system consisting of self-cleaning flexible pressure sensors with ultrahigh sensitivity (S max > 450 kPa−1) and flexible circuit board can wirelessly transmit the force signals. [Display omitted] Flexible tactile sensors (FTS), which have been extensively used in force sensing devices, are gaining tremendous attentions in various application fields, such as robots, electronic skin (E-Skin), human-machine interaction (HMI), and many other rapidly developing frontier technologies. However, fabricating FTS achieving both high sensitivity and broad sensing range remains a great challenge. Moreover, the integration of FTS with flexible circuit boards has long been a hot topic due to its potential applications in flexible hybrid electronics (FHEs). Here, we report a novel flexible tactile sensor with ultrahigh sensitivity and wide sensing range and its application in a self-cleaning and fully integrated wearable tactile sensing system for real-time analysis. Benefiting from the conductive sensing materials composed of fine inverted pyramid arrays and double-covered sensing layers, the sensor exhibits a superior sensitivity of 451.292 kPa−1, a wide working range up to 250 kPa, and a fast response time of 31 ms, as well as long-term durability. Furthermore, the sensor system can accurately monitor the grasped force in real-time and easily be fixed on a flexible clamping jaw or human hands. Our design concept and experimental approach, either for the flexible sensor or the whole system, potentially push further the wearable electronics toward practical applications. [ABSTRACT FROM AUTHOR]

Remarkable research efforts have been devoted to replicate the tactile sensitivity of human skin. Unfortunately, so far flexible pressure sensors reported barely fit the tactile requirements for fingertips, which could endure a pressure over 100 kPa and also can sense a gentle touch. It is vital to develop flexible pressure sensors which can ensure high sensitivity and wide operation range simultaneously, to satisfy the demands of mimicking the pressure sensing function of fingertips. In this work, a mini-size, light-weight but high-performance graphene film based pressure sensor is presented. Owing to the advanced structure with fluctuations on surface and fluffy-layered structure in cross-section of the graphene film, this pressure sensor shows an extraordinary performance of high sensitivity of 10.39 kPa-1 (0–2 kPa), ultra-wide operation range up to 200 kPa, impressively stable repeatability, high working frequency, rapid response and recovery time. Moreover, the demonstrated results of the detection of traditional Chinese medicine wrist-pulse waveform and the bionic fingertip tactile sensors, suggest the great application potential of the obtain device in biomedical field and bionic skins field. • Free-standing graphene film as active material of pressure sensors. • Widest operation range among flexible piezoresistive pressure sensors. • High sensitivity of 10.39 kPa-1 in 0–2 kPa. • Practicable applications for whist pulse detection and bionic fingertips. [ABSTRACT FROM AUTHOR]