Table 2.
Body worn sensor errors for estimating 3D body segment angles (peak and range of motion) during fast, medium, and slow speed movements.
Motion
Anterior-Posterior
Medial-lateral
Internal-external
Type of Error
Peak
Range
Peak
Range
Peak
Range
Abs
*
[°]
Re
**
[%]
Abs [°]
Re [%]
Abs [°]
Re [%]
Abs [°]
Re [%]
Abs [°]
Re [%]
Abs [°]
Re [%]
Fast Movement
Systematic
-1.37
-1.80
.51
.66
-.27
-.33
.07
.10
4.76
2.97
-2.07
-1.29
Random
1.90
2.47
3.70
4.80
.92
1.82
1.65
3.27
5.32
3.35
9.12
5.76
RMSE
†
2.21
2.88
3.35
4.35
1.42
2.84
1.50
2.98
6.81
4.26
8.43
5.32
Normal Movement
Systematic
-2.16
-2.55
.60
.71
-1.15
-2.46
.33
.70
2.56
1.83
-.83
-.59
Random
1.46
1.80
3.09
3.79
.76
1.73
1.48
3.32
2.09
1.47
3.85
2.72
RMSE
†
2.57
3.07
2.83
3.47
1.45
3.23
1.37
3.08
3.20
2.27
3.55
2.50
Slow Movement
Systematic
-.93
-1.16
.28
.36
-1.25
-2.77
.30
.67
-.99
-.66
.27
.20
Random
1.04
1.32
2.07
2.62
.71
1.67
1.52
3.54
1.34
.93
2.26
1.59
RMSE
†
1.41
1.78
1.88
2.37
1.45
3.27
1.40
3.25
1.58
1.07
2.05
1.43
* Absolute error value;
† Relative error value;
‡ Root mean square error