PhD Fekete - SZIE version - 2.2 - Szent István Egyetem

Materials and Methods
All the functions and standard deviation have been summarized in Table 3.6.
FUNCTION OR CONSTANT C1 C2 SD r 2
λ 1 (α) [-] 0.492 0.0024 0.15 0.65
λ 3 (α) [-] 0.86 -0.0022 0.22 0.63
β(α) [°] 26.56 -0.3861 14 0.95
ø(α) [-] 0.567 -0.0026 0.081 0.735
λ t [-] 0.11 0 0.018 -
λ p [-] 0.1475 0 0.043 -
λ f [-] 0.164 0 0.028 -
Table 3.6. Functions* and constants of the analytical-kinetical model
* The following equation is used: f(α) = C1 + C2· α
Where r 2 is the linear correlation coefficient between the original and modelled data values
regarding the λ 1 (α), λ 3 (α), β(α) and ø(α) functions and SD denotes the standard deviation. The
standard deviation and the correlation coefficient are considered normal compared to other
biomechanical measurements [Abe et al., 2010, Eames et al., 1999, Fukagawa et al., 2012].
3.4.8. Experimental results
The λ 1 (α) or λ 3 (α) functions give a view about the horizontal movement of the center of gravity
line under squatting motion. By substituting any α into the λ functions, the intersection of the
center of gravity line with the femur and tibia is obtained (Figure 3.23 and Figure 3.24).
λ 1 [-]
1
0.8
0.6
0.4
0.2
Average λ1 function
Standard deviation
Experimental data of λ1
Flexion angle [°]
0
40 60 80 100 120 140 160
Figure 3.23. Dimensionless λ 1 functions
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