## 4 Experimental Verification and Results Analysis
### Experimental Results and Analysis  
The following figure shows the effect graphs after the cooperative target is mounted on the rotary table, with the rotary table rotating in the azimuth range of 50\({}^{\circ}\) and the pitch  
Figure 11: Experimental verification platform of attitude dynamic measurement system based on rotary table. angle rotating in the range of 55\({}^{\circ}\), using the IMU alone measurement, the vision alone measurement, and the fusion based on the backpropagation algorithm, respectively. From Figure 12, we can see that the fused measurements have a higher data update rate and have a certain suppression effect on the error accumulation of the IMU. The absolute values of the errors of repeated multiple measurements at different distances and angles were statistically analyzed to obtain their average absolute value of error and maximum absolute value of error, as shown in Tables 2 and 3. From the measurement results in Tables 2 and 3, we can see that the absolute value of the fused error shows an upward trend with the increase in the measured angle, and the error becomes larger with the increase in the measurement distance. For the azimuth angle, the average absolute value of the error at 4 m is 0.057\({}^{\circ}\), the maximum absolute value of the error is 0.120\({}^{\circ}\), the average absolute value of the error at 8 m is 0.101\({}^{\circ}\), and the \begin{table}
\begin{tabular}{c c c c c} \hline
**Distance** & \multicolumn{2}{c}{**4 m**} & \multicolumn{2}{c}{**8 m**} \\ \hline
**Azimuth** & **Average Error** & **Max Error** & **Average Error** & **Max Error** \\ \hline
15\({}^{\circ}\) & 0.037\({}^{\circ}\) & 0.120\({}^{\circ}\) & 0.046\({}^{\circ}\) & 0.105\({}^{\circ}\) \\
25\({}^{\circ}\) & 0.039\({}^{\circ}\) & 0.042\({}^{\circ}\) & 0.042\({}^{\circ}\) & 0.093\({}^{\circ}\) \\
35\({}^{\circ}\) & 0.057\({}^{\circ}\) & 0.114\({}^{\circ}\) & 0.065\({}^{\circ}\) & 0.136\({}^{\circ}\) \\
45\({}^{\circ}\) & 0.031\({}^{\circ}\) & 0.059\({}^{\circ}\) & 0.053\({}^{\circ}\) & 0.092\({}^{\circ}\) \\
55\({}^{\circ}\) & 0.027\({}^{\circ}\) & 0.060\({}^{\circ}\) & 0.101\({}^{\circ}\) & 0.147\({}^{\circ}\) \\ \hline \end{tabular}
\end{table} 
Table 2: Standard deviation of azimuth measurement results at different distances and angles. Figure 12: Comparison of fusion effect and single measurement unit results at 4 m.  
\begin{table}
\begin{tabular}{c c c c c} \hline
**Distance** & \multicolumn{2}{c}{**4 m**} & \multicolumn{2}{c}{**8 m**} \\ \hline
**Pitch** & **Average Error** & **Max Error** & **Average Error** & **Max Error** \\ \hline
10\({}^{\circ}\) & 0.094\({}^{\circ}\) & 0.129\({}^{\circ}\) & 0.114\({}^{\circ}\) & 0.201\({}^{\circ}\) \\
20\({}^{\circ}\) & 0.143\({}^{\circ}\) & 0.189\({}^{\circ}\) & 0.174\({}^{\circ}\) & 0.231\({}^{\circ}\) \\
30\({}^{\circ}\)maximum absolute value of the error is 0.147\({}^{\circ}\). For pitch angle, the maximum absolute value of the mean error is 0.168\({}^{\circ}\), the maximum absolute value of the error is 0.250\({}^{\circ}\) at 4 m, the maximum absolute value of the error is 0.317\({}^{\circ}\) and 0.393\({}^{\circ}\) at 8 m.  
Figure 13 shows the comparative analysis chart between the results of the IMU-integrated solution and the data fusion solution. The horizontal axis of the chart represents the rotation angles of azimuth and pitch, with azimuth rotation angles at 15\({}^{\circ}\), 25\({}^{\circ}\), 35\({}^{\circ}\), 45\({}^{\circ}\), 55\({}^{\circ}\), and pitch rotation angles at 10\({}^{\circ}\), 20\({}^{\circ}\), 30\({}^{\circ}\), 40\({}^{\circ}\), 50\({}^{\circ}\). The vertical axis indicates the angular error between the IMU-integrated solution and the data fusion solution relative to the rotation values of a precision turntable. This angular error is calculated based on the mean error obtained from 10 independent experiments.