GT-PKU Joint PhD Proposal – Qingshen Jing

Date: Friday, November 28, 2014

Time: 4:00 PM

Location: Peking University

Committee:

Dr. Pingchou P.S. Han, co-advisor (PKU)

Dr. Zhong Lin Wang, co-advisor (GT)

Dr. Shulin Bai (PKU)

Dr. Ching-Ping Wong (GT)

Dr. Anyuan Cao (PKU)

Title:

Harvesting Triboelectric Energy for a Self-Powered Rectified Linear / Rotary Motion Sensor

Abstract:

Harnessing triboelectric energy is not only green but also, enables self-powered sensors and devices to be realized. In my research, I have fabricated a self-powered velocity sensor for either rectified linear or rotary motion by sourcing the energy from a triboelectric generator. Employing alternating Kapton-copper strips arranged in a spiral configuration wrapped on the inner and outer surfaces of two concentric cylinders, voltage assays for linear and rotary motions can be measured without the need for an external power source. The triboelectric generated output signals when integrated with a digital circuit and a microcontroller unit can be directly processed into remarkably stable, macro-scale output signals for measurements of (0.1-0.6) ms-1 ± 0.5% for linear velocities and (300-700) rpm ± 0.9% for rotary velocities. I have also fabricated a self-powered, thin-film motion direction sensor by harvesting the operational energy from a close-proximity triboelectrification of two surfaces in relative reciprocation. The mover made by coating a thin polytetrafluoroethylene film with a 2-column, specially arranged array of copper electrodes and the stator is made by coating the top and bottom surfaces of a thin polyimide film with a 2-column aligned array of copper electrodes placed in an alternating pattern. As the mover traverses over the stator, the electrodes in the mover actively generate electric signals of ±5 V to attain a peak power density of ≥ 65 mW/m2 at speeds of 0.3 ms-1. The highly pliable sensor can be easily bent to spread over curved and uneven surfaces. My work represents the first successful attempt in integrating a triboelectric generator into a commercial digital circuit for the dual-mode speed and direction sensing and I believe that my pioneering demonstration of the applied triboelectric technology will have a huge impact in the industrial commercialization of self-powered devices and sensors.