Table 2.

Output voltages with different mass ratios.

Group	θ	Resonant Frequency/Hz	Output Voltage/V
1	2.5 g:2.5 g	52	24.27
2	2.5 g:5 g	43	20.31
3	5 g:2.5 g	41	20.10
4	5 g:5 g	40	41.48
5	10 g:6 g	34	32.60
6	6 g:10 g	37	34.96
7	10 g:10 g	31	45.90