Multi-source Harvesting Systems for Electric Energy Generation on Smart Hip Prostheses - Biomedical Engineering Systems and Technologies - page 67

Fig. 7. Experimental (dotted line) and simulated (dashed line) energy (in the left) and peak-to-
peak voltage (in the right) harvested from the TEEH transducer

Ta b l e 1 . TEEH generator — modulation error (W) of the average power

Amplitude Frequency (Hz)

(mm) 0.5 1 1.5 2 2.5 3 3.5 4

0 . 06 (1) 0 . 009 (2) 0 . 05 (2) 0 . 02 (3) 0 . 04 (3) 0 . 08 (3) 0 . 02 (4) 0 . 03 (4)

10

0 . 02 (1) 0 . 02 (2) 0 . 11 (2) 0 . 04 (3) 0 . 08 (3) 0 . 18 (3) 0 . 03 (4) 0 . 05 (4)

15

0 . 13 (1) 0 . 04 (2) 0 . 20 (2) 0 . 06 (3) 0 . 15 (3) 0 . 31 (3) 0 . 05 (4) 0 . 09 (4)

20

0 . 26 (1) 0 . 06 (2) 0 . 31 (2) 0 . 10 (3) 0 . 23 (3) 0 . 47 (3) 0 . 08 (4) 0 . 12 (4)

25

0 . 43 (1) 0 . 09 (2) 0 . 44 (2) 0 . 14 (3) 0 . 32 (3) 0 . 62 (3) 0 . 10 (4) 0 . 18 (4) 30

0 . 62 (1) 0 . 12 (2) 0 . 60 (2) 0 . 19 (3) 0 . 39 (3) 0 . 71 (3) 0 . 14 (4) 0 . 26 (4)

35

0 . 85 (1) 0 . 15 (2) 0 . 78 (2) 0 . 24 (3) 0 . 48 (3) 0 . 85 (3) 0 . 19 (4) 0 . 35 (4) 40

(1)

× 10 − 7 ; (2) × 10 − 5 ; (3) × 10 − 4 ; (4) × 10 − 3 .

Ta b l e 2 . TEEH generator — modulation error (W) of the maximum power

Amplitude Frequency (Hz)

(mm) 0.5 1 1.5 2 2.5 3 3.5 4

0 . 70 (1) 0 . 03 (2) 0 . 01 (2) 0 . 01 (3) 0 . 001 (4) 0 . 01 (4) 0 . 01 (4) 0 . 02 (4)

10

0 . 30 (1) 0 . 02 (2) 0 . 06 (2) 0 . 03 (3) 0 . 003 (4) 0 . 01 (4) 0 . 02 (4) 0 . 02 (4)

15

0 . 54 (1) 0 . 01 (2) 0 . 15 (2) 0 . 05 (3) 0 . 01 (4) 0 . 02 (4) 0 . 0002 (4) 0 . 08 (4)

20

0 . 53 (1) 0 . 0002 (2) 0 . 27 (2) 0 . 07 (3) 0 . 02 (4) 0 . 003 (4) 0 . 06 (4) 0 . 26 (4)

25

0 . 48 (1) 0 . 05 (2) 0 . 35 (2) 0 . 11 (3) 0 . 004 (4) 0 . 09 (4) 0 . 23 (4) 0 . 29 (4)

30

0 . 37 (1) 0 . 04 (2) 0 . 39 (2) 0 . 13 (3) 0 . 09 (4) 0 . 32 (4) 0 . 25 (4) 0 . 22 (4)

35

0 . 69 (1) 0 . 12 (2) 0 . 64 (2) 0 . 03 (3) 0 . 17 (4) 0 . 44 (4) 0 . 22 (4) 0 . 14 (4)

40

(1)

× 10 − 6 ; (2) × 10 − 5 ; (3) × 10 − 4 ; (4) × 10 − 3 .

the modulation errors. The maximum energy harvested was 0 . 77 μ J/s. The “plus” sign
refers to peak-to-peak amplitudes in the range

− 10 ◦ to 60 ◦ , − 10 ◦ to 50 ◦ and − 10 ◦

to 40 ◦ ; the “square” sign refers to peak-to-peak amplitudes in the range

− 20 ◦ to 50 ◦ ,

− 20 ◦ to 40 ◦ and − 20 ◦ to 30 ◦ .