## 4 Experimental Examples
2 support leg. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Angles** & & **x Direction** & **y Direction** & **z Direction** \\ \hline \multirow{4}{*}{**55\({}^{\lx@sectionsign}\)**} & \(u^{act}\) & 2.29 mm & 17.10 mm & \(-\)0.73 mm \\  & \(u^{FEM}\) & \(-\)0.18 mm & 15.77 mm & \(-\)0.84 mm \\  & \(u^{cal}\) & 2.22 mm & 16.89 mm & \(-\)0.72 mm \\  & \(\delta(\%)\) & 3.06\% & 1.23\% & 1.37\% \\  & \(u^{act}\) & 1.90 mm & 14.25 mm & \(-\)0.61 mm \\
**40\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.25 mm & 12.79 mm & \(-\)0.69 mm \\  & \(u^{cal}\) & 1.88 mm & 14.26 mm & \(-\)0.60 mm \\  & \(\delta(\%)\) & 1.05\% & 0.07\% & 1.64\% \\  & \(u^{act}\) & 1.48 mm & 11.42 mm & \(-\)0.48 mm \\
**30\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.34 mm & 9.70 mm & \(-\)0.53 mm \\  & \(u^{cal}\) & 1.51 mm & 11.39 mm & \(-\)0.47 mm \\  & \(\delta(\%)\) & 2.03\% & 0.26\% & 2.08\% \\  & \(u^{act}\) & 0.78 mm & 5.99 mm & \(-\)0.25 mm \\
**15\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.29 mm & 4.65 mm & \(-\)0.26 mm \\  & \(u^{cal}\) & 0.81 mm & 5.92 mm & \(-\)0.24 mm \\  & \(\delta(\%)\) & 3.85\% & 1.17\% & 4.0\% \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Displacement and calibration error for No. 3 support leg. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Angles** & & **55\({}^{\lx@sectionsign}\)** & **40\({}^{\lx@sectionsign}\)** & **30\({}^{\lx@sectionsign}\)** & **15\({}^{\lx@sectionsign}\)** \\ \hline \multirow{4}{*}{**FBG strain/\(\mu\varepsilon\)**} & \(\varepsilon_{1}\) & \(-\)16 & \(-\)32 & \(-\)50 & \(-\)74 \\  & \(\varepsilon_{2}\) & \(-\)369 & \(-\)335 & \(-\)295 & \(-\)212 \\  & \(\varepsilon_{3}\) & 30 & 4 & \(-\)21 & \(-\)61 \\  & \(\varepsilon_{4}\) & \(-\)187 & \(-\)180 & \(-\)165 & \(-\)138 \\  & \(\varepsilon_{5}\) & 328 & 240 & 164 & 25 \\  & \(\varepsilon_{6}\) & \(-\)359 & \(-\)309 & \(-\)261 & \(-\)173 \\  & \(\varepsilon_{1}\) & 14 & 22 & 28 & 28 \\  & \(\varepsilon_{2}\) & 17 & 20 & 26 & 29 \\
**FBG temperature** & \(\varepsilon_{3}\) & 27 & 30 & 38 & 34 \\
**compensation/\(\mu\varepsilon\)** & \(\varepsilon_{4}\) & 9 & 18 & 24 & 27 \\  & \(\varepsilon_{5}\) & 35 & 36 & 38 & 36 \\  & \(\varepsilon_{6}\) & 12 & 21 & 25 & 29 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: FBG strains and temperature compensation for No. 3 support leg. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Angles** & & **x Direction** & **y Direction** & **z Direction** \\ \hline \multirow{4}{*}{**55\({}^{\lx@sectionsign}\)**} & \(u^{act}\) & 1.93 mm & 16.90 mm & \(-\)1.52 mm \\  & \(u^{FEM}\) & \(-\)0.22 mm & 18.91 mm & \(-\)1.39 mm \\  & \(u^{cal}\) & 1.88 mm & 16.70 mm & \(-\)1.50 mm \\  & \(\delta(\%)\) & 2.59\% & 1.18\% & 1.32\% \\  & \(u^{act}\) & 1.60 mm & 14.12 mm & \(-\)1.27 mm \\
**40\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.27 mm & 15.57 mm & \(-\)1.13 mm \\  & \(u^{cal}\) & 1.58 mm & 14.11 mm & \(-\)1.26 mm \\  & \(\delta(\%)\) & 1.25\% & 0.07\% & 0.79\% \\  & \(u^{act}\) & 1.25 mm & 11.47 mm & \(-\)1.03 mm \\
**30\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.33 mm & 12.07 mm & \(-\)0.86 mm \\  & \(u^{cal}\) & 1.26 mm & 11.39 mm & \(-\)1.02 mm \\  & \(\delta(\%)\) & 0.80\% & 0.70\% & 0.97\% \\  & \(u^{act}\) & 0.66 mm & 6.17 mm & \(-\)0.55 mm \\
**15\({}^{\lx@sectionsign}\)** & \(u^{FEM}\) & \(-\)0.27 mm & 6.02 mm & \(-\)0.41 mm \\  & \(u^{cal}\) & 0.67 mm & 6.07 mm & \(-\)0.54 mm \\  & \(\delta(\%)\) & 1.52\% & 1.62\% & 1.82\% \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Displacement and calibration error for No. 4 support leg. In order to further verify the effectiveness of the temperature compensation device designed in this paper, the strain data under the elevation of \(55^{\circ}\) at noon and from the No. 1 support leg was used. In this case, the strain value \(\epsilon^{comp}(x_{i},\theta_{i},\beta_{i})\) was obtained by Equation (10). It can be seen from Table 10 that the temperature has a great influence on strain measurement. However, when the measured strains, \(\epsilon\), are compensated, \(\epsilon^{comp}\) becomes stable.