Design, Modeling, and Simulation of Two-Piece Trapezoidal Piezoelectric Devices for Sensing and Energy Harvesting

Table 2

Resonance frequency when the widths of the bimorph change.

Width W1	Width W2	Thickness 2 Tp + Ts	Resonance fr
2 mm	40 mm	0.65 mm	14.5 Hz
6 mm	40 mm	0.65 mm	17.4 Hz
10 mm	40 mm	0.65 mm	18.7 Hz
14 mm	40 mm	0.65 mm	19.5 Hz
18 mm	40 mm	0.65 mm	20.0 Hz
2 mm	44 mm	0.65 mm	14.3 Hz
6 mm	44 mm	0.65 mm	17.1 Hz
10 mm	44 mm	0.65 mm	18.5 Hz
14 mm	44 mm	0.65 mm	19.4 Hz
18 mm…	44 mm…	0.65 mm…	19.9 Hz…

Note: the length of the beam is 60 mm (the first trapezoidal design). The variable widths, thickness, and the first real resonance frequency of the two-piece trapezoidal composite beams with no tip mass (two out of six iterations of W₁ and W₂ incremental pattern, the total of ten permutations of W₁ and W₂ out of 30 geometry permutations). The imaginary part of the resonance f_r is ignored as the imaginary part indicates the damping of the structure.