Table 1.
Turn onset detection using an orientation threshold and various IMU positions in within-subject and subject-independent crossvalidation. CD = correct detection, PLD = premature/late detection, FN = false negatives, FP = false positives, DIFF = mean difference between detected and reference onset.
| CD (%) | PLD (%) | FN (%) | FP (%) | DIFF (ms) | ||
|---|---|---|---|---|---|---|
| within-subject | head | 57.7 | 33.7 | 8.6 | 17.7 | −70 |
| upper back | 76.2 | 21.7 | 2.1 | 4.8 | 295 | |
| lower back | 73.8 | 24.3 | 1.8 | 12.9 | 233 | |
| thigh | 66.0 | 32.6 | 1.3 | 14.1 | 235 | |
| shank | 57.2 | 42.5 | 0.2 | 17.3 | 238 | |
| foot | 46.7 | 51.2 | 2.0 | 25.2 | −153 | |
|
| ||||||
| subject-independent | head | 58.1 | 31.3 | 10.7 | 8.3 | 179 |
| upper back | 74.3 | 24.9 | 0.8 | 11.0 | 156 | |
| lower back | 68.7 | 30.4 | 0.8 | 8.1 | 168 | |
| thigh | 54.5 | 44.6 | 0.0 | 9.7 | 213 | |
| shank | 47.1 | 52.4 | 0.0 | 14.5 | 199 | |
| foot | 36.7 | 56.8 | 6.5 | 35.7 | −118 | |