mar/content/case_experiment_test_protocol.tex

%&tex
\subsection{Test Protocol}
    The last step of the preparation phase is to design tests.
    The tests are designed to validate if the system meets the specifications.
    Defining the tests highlighted some shortcomings in the specifications.
    The specifications were made before the initial design and the feature definition, and were therefore not taken into account.
    Making it impossible to create simple concrete tests.
    To improve the specifications, an order of operation and additional specifications are determined.

    \subsubsection{Defining the Order of Operation}
    There are two modes of operation: writing and wiping.
    Defining the order of operation also distributes the responsibility between the different components.
    The writing operation can be split in the following steps:
    \begin{order}{Writing}
        \emph{Precondition:} Marker as end-effector.
        \begin{enumerate}
            \item Move cable driven carriage to position of characters.
            \item Write three characters with the SCARA.
            \item Repeat step 1 and 2 till the Tweet is on the board.
            \item Move carriage away from the text on the board.
        \end{enumerate}
    \end{order}

    The other operation is wiping.
    This is similar to the operation of writing with the following steps:
    \begin{order}{Wiping}
        \emph{Precondition:} Wiper as end-effector.
        \begin{enumerate}
            \item Move cable driven carriage to position of characters.
            \item Clear the area in reach of the SCARA.
            \item Repeat step 1 and 2 till the Tweet is removed from on the board.
        \end{enumerate}
    \end{order}
    Furthermore, switching between the states requires the tool to be switched.
    However, at this point, it is not known how tools will be switched.
    Therefore, the order of operation is determined during the development of the end-effector.
    Additionally, the missing order of operation for the end-effector did not result in difficulty while defining the tests.

    \subsubsection{Improving Specifications}
    Based on the order of operation, the following specifications were added to the list in \autoref{sec:specifications}:
    \begin{enumerate}
        \setcounter{enumi}{11}
        \item While writing, the SCARA shall have a writing speed of at least 1.5 characters per second.
        \item When the Carriage/base of the SCARA is at a static position, the SCARA shall be able to write at least 3 characters at that position.
        \item When the SCARA finished writing at their current position, the Carriage shall move the SCARA to it's next position where it can write the subsequent characters.
        \item When the SCARA has to be moved to a new position, the Carriage shall perform this movement within 1 second.
    \end{enumerate}
    These additional specifications are also based on the combined system decission that was made in section \autoref{sec:initialdesign}.
    These specifications distribute responsibility between sub-components.

    With the updated specifications it was possible to create a number of test cases.
    In total there are five small test cases and four large test cases.
    The small tests cover a sub-system and the large tests apply on the complete systems.
    Each tests has a list of specifications that are covered with the test and for smaller tests the subsystem under test is also determined.
    With a short description it is described how the test should be performed.

    One of the small tests is performed by drawing a square:
    \begin{test}{Box}
        \begin{description}
            \item[Coverage] SCARA
            \item[Specifications] 3, 7, 11, 13
            \item[Description]
                The SCARA must draw a square of at least \SI{50}{\milli\meter} high and \SI{70}{\milli\meter} wide.
                This box is large enough to draw at least 3 characters.
                This square should be drawn within one second.
                If it is slower than that, it is not able to achieve specification 7.
        \end{description}
    \end{test}
    Repeatability is tested in one of the large system wide tests:
    \begin{test}{Repeatability}
        \begin{description}
            \item[Coverage] All features
            \item[Specifications] 3, 4, 9, 11
            \item[Description]
                To test the repeatability of the system must do four things:
                \begin{itemize}
                    \item The system will be reset.
                    \item Draw multiple squares (\SI{60}{\milli\meter} x \SI{60}{\milli\meter}) at a random position within the drawing range (\SI{1000}{\milli\meter} x \SI{300}{\milli\meter}).
                    \item The system will be reset again.
                    \item Then in a random order, at least different from the order of squares, a circle with a \SI{55}{\milli\meter} diameter must to be drawn inside the squares.
                \end{itemize}
                The test is successful if the circles are not drawn outside of the squares.
        \end{description}
    \end{test}

    \subsubsection{Evaluation}
        This step was completed with not many difficulties.
        The specific order of operation and extra specifications should not be part of this step.
        It was already concluded that the steps in the preliminary design were not as expected.
        The fact that this step resulted in an additional changes only adds to that conclusion.

        The design of the test cases resulted in valuable information about the system.
        This information would be very useful in an earlier stage of the preliminary design.