IEEE Trans Ultrason Ferroelectr Freq Control. 2020 Apr;67(4):840-849. doi: 10.1109/TUFFC.2019.2956773. Epub 2019 Nov 29.
This article presents the design and testing of a novel two-directional (2-D) piezoelectric stack-based energy harvester for capturing the mechanical energy from the human footstep. The uniqueness of the harvester lies in the fact that the energy of 2-D excitation is scavenged by a single piezoelectric stack transducer, which can reduce the loss of harvestable energy. The harvester is constructed by the integration of permanent magnets, position protection plates, and multistage force amplification frame. The input force and input displacement are restricted to guarantee the device's safety. The reported multistage force amplification frame with leverage mechanism and bridge-type amplifier enlarges the force acting on the piezoelectric stack, which further improves the power output. A linear guiding mechanism based on leaf flexure is applied to minimize the impact of input forces in other than moving directions. Through analytical modeling, the main architectural parameters of the device are determined. Simulation study with finite-element analysis is conducted to optimize the device parameters for achieving the largest force amplification ratio with a high safety factor. A prototype harvester is fabricated for experimental study. Results demonstrate the feasibility of the developed 2-D piezoelectric stack-based energy harvester.
本文提出了一种新颖的基于双向（2-D）压电堆叠的能量收集器的设计和测试，用于从人脚步中捕获机械能。该收集器的独特之处在于，2-D 激励的能量可以被单个压电堆叠换能器收集，从而减少可收集能量的损失。该收集器通过集成永磁体、位置保护板和多级力放大框架构建而成。输入力和输入位移受到限制，以保证设备的安全。所报道的具有杠杆机构和桥式放大器的多级力放大框架放大了作用在压电堆叠上的力，从而进一步提高了功率输出。基于叶片挠曲的线性导向机构用于最小化非移动方向上输入力的影响。通过解析建模，确定了设备的主要结构参数。通过有限元分析进行仿真研究，以优化设备参数，实现最大的力放大比和高安全系数。制造了一个原型收集器进行实验研究。结果表明，所开发的基于 2-D 压电堆叠的能量收集器是可行的。
