assigned the portions

documentation/Ahmed/galign.tex

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+\section{Goal Alignment}
+\label{p sec goal align}
+
+After the approach, described in the section \ref{p sec approach}, is finished,
+the robot is facing the ball, and the ball is at a short distance. In the stage
+of goal alignment, the task is to ensure that from the robot's point of view
+the ball lies between the goalposts. This means, that when the robot is
+centered at the ball, the goalposts should lie on either side of the center of
+the camera image. So the robot will first detect the goal and determine if that
+is the case. If that is not the case, the robot will go around the ball in a
+circle in the appropriate direction, until the ball is indeed between the
+goalposts.
+
+The walk in circle was implemented in the following way: the robot will step
+several steps sideways, then will turn to ball, as described in the section
+\ref{j sec turning to ball}, and finally will adjust the distance to the ball
+by stepping forwards or backwards, so that the ball is neither too close nor
+too far. The distance to the ball, similarly to the stage of the direct
+approach, is not measured explicitly, but is approximated through the position
+of the ball image in the camera frame. After performing these steps, the check
+is performed, if the goal alignment is completed. Otherwise, the steps will be
+repeated until alignment is achieved. The figure \ref{p figure goal-alignment}
+depicts the successful completion of this stage.
+
+\begin{figure}[ht]
+  \includegraphics[width=\textwidth]{\fig goal-alignment}
+  \caption{Successful goal alignment}
+  \label{p figure goal-alignment}
+\end{figure}