As a pivotal component in human-machine interface and autonomous robot, tactile sensors are imperative to own extra capability of perceiving transient mechanical stimuli, rather than remaining in the static sensing regime. In this work, a hybrid tactile sensor is proposed, which integrates a porous polydimethylsiloxane (PDMS) based triboelectric nanogenerator active sensing unit and a conductive carbon black (CB)/thermoplastic polyurethane (TPU) composites based piezoresistive sensing unit. This hybrid sensor responds well to both static and transient mechanical excitations, such that the entire process of "approach-contact-press-release-separation" in a tactile stimulus can be precisely distinguished. In addition, this sensor can detect the approaching and separating speed up to 100 mm?s-1, with a good linearity between the contact or separation speed and the triboelectric voltage output. The two signals from the hybrid sensor can be combined to generate comprehensive and insightful information about a mechanical stimulus and differentiate nuances among similar stimuli. We demonstrate the application of the hybrid sensor as part of a smart boxing-training glove, which is capable of identifying different boxing punches and revealing detailed information about the impact of each punch.
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