Research on Self-Powered Coded Angle Sensor for Rock Climbing Training

Abstract

Rock climbing speed is an important indicator for coaches to evaluate athletes, so it is necessary to be monitored in real-time. Rock climbing speed is currently measured by an angle sensor, but an angle sensor with self-powered function will be more suitable for actual working conditions. Triboelectric nanogenerators originate from triboelectric and electrostatic induction phenomena, and if sensors are developed based on the triboelectric nanogenerators, they will have self-powered function. In this research, a self-powered coded angle sensor which can measure the rotation angle, rotation direction, and rotation speed is proposed based on a single-electrode triboelectric nanogenerator. The power generation test results show that the maximum output power is about <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$9.5\times 10$ </tex-math></inline-formula> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−7</sup> W with a load resistance of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{6} \Omega $ </tex-math></inline-formula> . The sensing test results show that the resolution of angle measurement is 22.5°, the measurement range of rotation speed is 0–900 r/min, the measurement error is less than 5%, and the working temperature and humidity range are 0 °C–160 °C and 0%–90%, respectively. Compared with the conventional rock climbing sensor, the sensor has the function of self-powered function. It can effectively avoid the potential safety hazard caused by the power cable of the traditional indoor rock climbing sensor entangled with athletes and can also extend the application range of the sensor to the wild climbing environment without a power supply.