The low-altitude transport has demonstrated significant growth potential driven by rapid advancements in unmanned aerial vehicles (UAVs) technology. Herein, rotor UAVs are increasingly favored by consumers due to their unique advantages. The UAVs motion is altered by adjusting propeller speed, which is governed by motor speed. Consequently, motor speed is a key factor influencing flight performance that is susceptible to environmental interference. Accurate and real-time monitoring of motor speed is essential. Conventional speed sensors are bulky, reliant on external power, and challenging to integration into compact UAVs systems. They also suffer from insufficient accuracy and unstable measurements, particularly with small motors. This article introduces a self-powered digital aircraft rotational speed sensor (SDARSS) utilizing a rotating triboelectric nanogenerators (TENGs) to address current challenges. This sensor is lightweight, energy-efficient, and self-powered, weighing only 2.185 g and measuring 3.43 mm in thickness, with an accuracy exceeding 99.94%. It measures speeds up to 10,000 revolutions per minute (rpm) with exceptional precision and stability. The sensor enables real-time monitoring of UAVs motor speeds, which is crucial for enhancing flight safety.

Existing nanogenerator technologies for harvesting high-power energy from wind encounter significant challenges due to limitations in current output. Here, we propose a rotating-switch triboelectric nanogenerator (RS-TENG) that uses mechanical triggering switches (on-off-on) to enhance the instantaneous current pulses during rotation. The rotating-switch in the proposed device addresses the issue of low instantaneous current output in triboelectric nanogenerators while maintaining voltage stability. At a constant rotational speed, the RS-TENG achieves an instantaneous current of 3.2 times that of its nonswitching counterpart, with an 89% reduction in response time. Furthermore, at a wind speed of 2 m·s⁻¹, the RS-TENG achieves a wind power density of 10.4 mW·m⁻²·m⁻¹·s. Additionally, by integrating the RS-TENG with energy management circuits, the nanogenerator can power wireless signal transmitters and temperature sensors, offering a self-sustaining power solution for remote wireless services. This research presents a promising technology for powering electronic devices in energy-scarce environments.