# Augmented Reality-Based Interface for Bimanual Robot Teleoperation
## 4 Results
In particular, it can be appreciated that the trajectory described by the workpiece corresponds closely to the user reference values, except obviously when the 3D boundary constraint is active; see the bottom graph in Figure 15. In fact, the maximum  
Figure 14: The 3D trajectory performance for the third experiment, showing the 3D boundary and the WR reference hologram (see the video at [[https://media.upv.es/player/?id=17d88200-8f0b-11](https://media.upv.es/player/?id=17d88200-8f0b-11) ec-be2-d786 eca82090]([https://media.upv.es/player/?id=17d88200-8f0b-11](https://media.upv.es/player/?id=17d88200-8f0b-11) ec-be2-d786 eca82090) (accessed on 26 April 2022) [83]): 3D allowed region in green; trajectory followed by the user reference in thin red line; and trajectory followed by the WR end-effector in thick blue line. Figure 13: Third experiment: frames of the video showing the performance of the 3D boundary and the WR reference hologram. See the video at [[https://media.upv.es/player/?id=17d88200-8f0b-11](https://media.upv.es/player/?id=17d88200-8f0b-11) ec-be22-d786 eca82090]([https://media.upv.es/player/?id=17d88200-8f0b-11](https://media.upv.es/player/?id=17d88200-8f0b-11) ec-be22-d786 eca82090) (accessed on 26 April 2022) [83]. **(a)** Video: 0 m 22 s. **(b)** Video: 0 m 24 s. **(c)** Video: 1 m 04 s. **(d)** Video: 1 m 46 s.  
deviation of the actual workpiece position values compared to the user reference values, when the 3D boundary constraint was not active, was around 1.2 cm, with a standard deviation of around 0.4 cm; see Table 3. Moreover, the maximum deviation of the actual workpiece orientation values compared to the user reference values was around 1.7\({}^{\circ}\), with a standard deviation of around 0.3\({}^{\circ}\); see Table 3. Note that these teleoperation error values include all the potential sources of error: communication delays, high-level and low-level robot control, teleoperation system, etc. Therefore, it can be concluded that the accuracy of the proposed AR-based teleoperation of the WR is sufficient for the task at hand. Figure 17 depicts several frames of the _fourth experiment_, which shows the performance of the overall system when the user commands simultaneously both robots using the proposed AR-based interface; see the video at [[https://media.upv.es/player/?id=29330720](https://media.upv.es/player/?id=29330720)]([https://media.upv.es/player/?id=29330720](https://media.upv.es/player/?id=29330720)) \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Position (cm)**} & \multicolumn{3}{c}{**Orientation (deg)**} \\  & \(\mathbf{x}\) & \(\mathbf{y}\) & \(\mathbf{z}\) & \(\mathbf{\alpha}\) & \(\mathbf{\beta}\) & \(\mathbf{\gamma}\) \\ \hline Maximum deviation & 1.2 & 0.9 & 0.1 & 1.7 & 1.5 & 1.7 \\ \hline Standard deviation & 0.4 & 0.3 & 0.03 & 0.3 & 0.2 & 0.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Teleoperation errors for the pose \(\mathbf{p}_{w}\) (i.e., position and orientation) of the WR. Figure 15: Performance of the WR position teleoperation for the third experiment. First three graphs: user position references in thin red line, actual position values of the workpiece in thick blue line, and position limits given by the 3D boundary constraint in dashed lines. Bottom graph: activation of the 3D boundary constraint for the workpiece position. -8a8b-11 ec-97 cd-ab744f931636 (accessed on 26 April 2022) [84]. Figure 17a-d show how the user modifies the orientation of the WR while, at the same time, commanding the STR tool towards one side of the workpiece. Note that, in this situation, when the WR end-effector is close to one side of the 3D boundary, it is partially shown by the corresponding blue hologram. Furthermore, Figure 17e shows how the user simultaneously commands both robots to reach both 2D and 3D boundaries, which are partially shown by the red and blue holograms, respectively. It is worth noting that, in addition to the mentioned holograms, the user hears different warning sounds.