# Virtual Reality-Based Interface for Advanced Assisted Mobile Robot Teleoperation
## 3 Results
### Usability Analysis Results
\begin{table}
\begin{tabular}{c l} \hline \hline PQ1 & How much were you able to control events? \\ \hline PQ2 & How responsive was the environment to actions that you initiated (or performed)? \\ \hline PQ3 & How natural did your interactions with the environment seem? \\ \hline PQ4 & How much did the visual aspects of the environment involve you? \\ \hline PQ5 & How natural was the mechanism which controlled movement through the environment? \\ \hline PQ6 & How compelling was your sense of objects moving through space? \\ \hline PQ7 & How much did your experiences in the virtual environment seem consistent with your \\  & real world experiences? \\ \hline PQ8 & How compelling was your sense of moving around inside the virtual environment? \\ \hline PQ9 & How completely were you able to actively survey or search the environment using vision? \\ \hline PQ11 & How well could you move or manipulate objects in the virtual environment? \\ \hline PQ12 & How closely were you able to examine objects? \\ \hline PQ13 & How well could you examine objects from multiple viewpoints? \\ \hline PQ14 & How much did the auditory aspects of the environment involve you? \\ \hline PQ15 & How well could you identify sounds? \\ \hline PQ16 & How well could you localize sounds? \\ \hline PQ17 & Were you able to anticipate what would happen next in response to the actions that \\  & you performed? \\ \hline PQ18 & How quickly did you adjust to the virtual environment experience? \\ \hline PQ19 & How proficient in moving and interacting with the virtual environment did you feel at \\  & the end of the experience? \\ \hline PQ20 & How well could you concentrate on the assigned tasks or required activities rather \\  & than on the mechanisms used to perform those tasks or activities? \\ \hline PQ21 & How much delay did you experience between your actions and expected outcomes? \\ \hline PQ22 & How much did the visual display quality interfere or distract you from performing \\  & assigned tasks or required activities? \\ \hline PQ23 & How much did the control devices interfere with the performance of assigned tasks or \\  & with other activities \\ \hline PQ24 & How much did the control devices interfere with the performance of assigned tasks or \\  & with other activities \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Questions of the PQ questionnaire [75; 76]. _fidelity_ score was 99.13% with a standard deviation of 2.26, which means that the users could observe from multiple views and interact with all objects present in the VE easily and without problems. The _immersion_ score was 94.48% with a standard deviation of 6.05, which means that users could adapt themselves quickly and easily to the VE, and could perform the task without distractions. Finally, the _interface quality_ score was 97.40% with a standard deviation of 3.92, which means that users did not perceive failures or malfunctions in the virtual reality interface during the tasks. On the other hand, the IPQ was conducted in order to measure the sense of presence experienced by users in the proposed VE [77]. The IPQ is composed of 14 questions used to evaluate three subscales: _spatial presence_, i.e., the sense of being physically present in the VE; _involvement_, i.e., measuring the attention devoted to the VE and the involvement experience; and _experienced realism_, i.e., measuring the subjective experience of realism in the VE. In addition to this, the IPQ has an additional general item that assesses the general \"sense of being there\", and has high loadings on all three factors, especially on spatial presence. The IPQ questions are shown in Table 2.  
Figure 11 shows the results of the IPQ. Concretely, Figure 11 shows the mean, and standard deviation for each question of the IPQ, whilst Figure 11 shows the mean, standard deviation and total percentage for each PQ subscale. In particular, the _general presence_ score was 94.81% with a standard deviation of 6.87, which indicates that users felt like they were inside the VE.