Human‐machine interfaces (HMIs) play important role in the communication between humans and robots. Touchless HMIs with high hand dexterity and hygiene hold great promise in medical applications, especially during the pandemic of coronavirus disease 2019 (COVID‐19) to reduce the spread of virus. However, current touchless HMIs are mainly restricted by limited types of gesture recognition, the requirement of wearing accessories, complex sensing platforms, light conditions, and low recognition accuracy, obstructing their practical applications. Here, an intelligent noncontact gesture‐recognition system is presented through the integration of a triboelectric touchless sensor (TTS) and deep learning technology. Combined with a deep‐learning‐based multilayer perceptron neural network, the TTS can recognize 16 different types of gestures with a high average accuracy of 96.5%. The intelligent noncontact gesture‐recognition system is further applied to control a robot for collecting throat swabs in a noncontact mode. Compared with present touchless HMIs, the proposed system can recognize diverse complex gestures by utilizing charges naturally carried on human fingers without the need of wearing accessories, complicated device structures, adequate light conditions, and achieves high recognition accuracy. This system could provide exciting opportunities to develop a new generation of touchless medical equipment, as well as touchless public facilities, smart robots, virtual reality, metaverse, etc.

Hydraulics provide a unique and widely existed mechanical energy source around us, such as in water or oil pipes, and sewers. Here, a non-contact cylindrical rotating triboelectric nanogenerator (TENG) was developed to harvest the mechanical energy from water flows. Operation of the TENG was based on the non-contact free-rotating between a curved Cu foil and a flexible nanostructured fluorinated ethylene propylene (FEP) polymer film. The free-standing distance between two rotating interfaces avoided abrading of electrode materials. The TENG was able to effectively convert mechanical energy of the water flow into electricity. When driven by water flow, the output voltage and current of the TENG reached 1,670 V and 13.4 μA, respectively. Without any energy storage component, the produced electricity could instantaneously power 12 white light emitting diodes (LEDs) bulbs and a digital timer. This non-contact rotating TENG would provide new opportunities for harvesting energy from many types of hydraulics as a self-sustainable power source for sensing, detection, and protection.

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