An Approach For The Design And Validation Of High Frequency Vibration Energy Harvesting Devices

The aim of this work is to explore a topology optimisation approach for the design of high frequency vibration energy harvesting devices capable of operating in the range of 1800-2600 Hz. The main objective of the approach is to develop an optimisation algorithm for tailoring the resonant behaviour of the cantilever energy harvesters to the dominant frequencies of the available vibrations present in a Bell 206B-1 Kiowa helicopter main rotor gearbox. Hence, the devices designed are to be operated in the high frequency, highly loaded, extreme environments commonly found on aircraft structures. A multi-physics model capable of predicting the performance of the developed cantilever energy harvesters is presented and the design optimisation problem is formulated and then solved with the bi-directional evolutionary structural optimisation method. Two designs were experimentally validated; one that is sensitive to a single mode in the range 1800-2600 Hz equipped with a single transducer having a 6.35 mm diameter and 0.5 mm thickness and the other sensitive to three modes in the same range equipped with two transducers. Output powers of 0.3-3.1 mW were measured, demonstrating the approach's potential to design harvesters capable of powering many useful sensor types.