\subsection{Obstacle Avoidance Tasks}\label{oaTasks}

\begin{figure}[t]
\centering
\includegraphics[width=0.49\textwidth]{oamap1}
\vspace{2mm}
\includegraphics[width=0.49\textwidth]{oamap2}
\caption[Training course map]{Two views of the Training Course Virtual Environment map captured from diagonally opposite corners of the environment}
\label{fig:oamap}
\end{figure}

\begin{figure}[h!]
\centering
\includegraphics[width=0.49\textwidth]{wall1}
\vspace{2mm}
\includegraphics[width=0.49\textwidth]{wall2}
\caption[Wall Following in Empty Hall map]{\textit{Left} - A view of the Empty Hall VE. \textit{Right} - Wheelchair following a wall in the Empty Hall VE keeping an arm's distance (approximately 65cm) from the wall, i.e., keeping within a zone of 6 tiles marked in red}
\label{fig:wfmap}
\end{figure}

The obstacle avoidance tasks were conducted in the Training Course Virtual Environment (VE) shown in \hyperref[fig:oamap]{Figure 5.2}. A well-defined path within this environment was pointed out to the volunteer. The first half of the path contained widely spaced obstacles, while the latter half contained very narrow spaces such as those explained in \hyperref[chairBehaviour]{Section 4.2}. The volunteers were told they were in control in both manual and shared modes, and had to guide the wheelchair through the path. However, shared control would step in if they were too close to an obstacle. It would also not allow them to proceed in certain directions if bound by obstacles, in which case, they were told to use the \textquoteleft{Reverse}' command to reverse the wheelchair, alter its direction to find a clearing and then proceed.

