Table 2.
Summary of 10-subject individual average values of RMSE, R2, C0, estimated CRT, the time to reach the stable blood volume, the ratio between the amplitudes A2 and A1; all these features were calculated from the fitting curves (in blue). Additionally shown are the PI and (P–P)ave interval values, which were calculated from the refilling signals (columns 8 and 9). Underfoot temperature and applied and released pressure were obtained from the data logger and the FBG sensor, respectively.
| No. | Average Values | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| RMSE | R2 | C0 | CRT (s) | Stable Blood Volume (s) | Ratio A2/A1 | PI (%) | (P-P)ave Interval (s) | Temp. (°C) | Pressure (kPa) | ||
| ON | OFF | ||||||||||
| P1 | 0.028 | 0.97 | −1.66 × 10−5 | 0.91 | 3.91 ± 1.19 | 9.70 ± 4.24 | 1.21 ± 0.29 | 0.66 ± 0.01 | 33.0 | 105.22 | 9.71 |
| P2 | 0.035 | 0.94 | −2.42 × 10−5 | 0.82 | 3.09 ± 0.36 | 7.90 ± 3.45 | 1.00 ± 0.33 | 0.66 ± 0.02 | 32.8 | 104.94 | 12.50 |
| P3 | 0.033 | 0.96 | −2.11 × 10−5 | 0.84 | 3.33 ± 0.32 | 9.40 ± 3.57 | 1.47 ± 0.52 | 0.70 ± 0.03 | 31.7 | 97.34 | 10.32 |
| P4 | 0.043 | 0.91 | −2.08 × 10−5 | 0.93 | 3.57 ± 1.14 | 20.11 ± 5.06 | 2.45 ± 0.21 | 0.69 ± 0.04 | 30.0 | 94.56 | 10.33 |
| P5 | 0.021 | 0.99 | 2.38 × 10−6 | 1.41 | 8.35 ± 0.49 | 38.50 ± 9.63 | 0.61 ± 0.11 | 0.76 ± 0.04 | 28.7 | 97.03 | 7.44 |
| P6 | 0.035 | 0.98 | 1.22 × 10−5 | 1.82 | 5.58 ± 0.94 | 17.63 ± 7.73 | 2.02 ± 0.16 | 0.77 ± 0.04 | 29.0 | 101.25 | 9.51 |
| P7 | 0.028 | 0.97 | 1.25 × 10−5 | 1.65 | 6.27 ± 2.45 | 24.00 ± 5.34 | 1.21 ± 0.12 | 0.74 ± 0.04 | 28.8 | 102.67 | 8.56 |
| P8 | 0.041 | 0.96 | 9.03 × 10−6 | 1.44 | 5.04 ± 0.49 | 13.50 ± 3.47 | 2.60 ± 0.32 | 0.67 ± 0.02 | 32.7 | 109.62 | 7.93 |
| P9 | 0.034 | 0.98 | 1.58 × 10−5 | 1.89 | 5.95 ± 0.49 | 12.70 ± 1.77 | 1.59 ± 0.20 | 0.70 ± 0.04 | 34.1 | 96.94 | 8.23 |
| P10 | 0.039 | 0.97 | 1.59 × 10−5 | 1.94 | 6.17 ± 0.88 | 14.20 ± 4.80 | 1.89 ± 0.17 | 0.69 ± 0.03 | 34.5 | 102.21 | 7.32 |