diff --git a/submission_thesis/CH4_FMMD/copy.tex b/submission_thesis/CH4_FMMD/copy.tex index 368fe8c..8129633 100644 --- a/submission_thesis/CH4_FMMD/copy.tex +++ b/submission_thesis/CH4_FMMD/copy.tex @@ -69,7 +69,7 @@ These {\dcs} are used to then build further {\fgs} until a hierarchy of {\fgs} and {\dcs} has been built, converging to a final {\dc} at the top of the hierarchy. % -Or in other words we take the traditional FMEA process, and modularise it. +Or in other words we take the traditional FMEA~\cite{sccs}[pp.34-38] process, and modularise it. We break down each stage of reasoning into small manageable groups, and use the results of those groups, as {\dcs} to build higher level groups. @@ -530,7 +530,7 @@ and determine how they affect the operation of the potential divider. %which is represented on the diagram, with an asterisk marking %which failure modes is modelling (see figure \ref{fig:fg1a}). % -For this example we look at single failure modes only. +%%For this example we look at single failure modes only. For each failure mode in our {\fg} `potential~divider', we can assign a {\fc} number (see table \ref{tbl:pdfmea}). Each {\fc} is analysed to determine the `symptom' @@ -540,7 +540,7 @@ voltage output from it would float high (+ve). This would mean the symptom of the failed potential divider would be voltage high output. % The failure symptom of a high potential divider output is termed `HighPD', and -for it outputing a low voltage `LowPD'. % Andrew asked for this to be defined before the table. ... +for it outputting a low voltage `LowPD'. % Andrew asked for this to be defined before the table. ... %We can now consider the {\fg} %as a component in its own right, and its symptoms as its failure modes. @@ -550,6 +550,12 @@ for it outputing a low voltage `LowPD'. % Andrew asked for this to be defined be \centering % used for centering table \begin{tabular}{||l|c|c|l||} \hline \hline +% FUCKING HATE HAVING TO REMOVE THE TERM FAILURE SCENARIO HERE.... +% GOOD ENOUGH FOR THE IET/IEEE, but then they live in the real +% world don't they.... + %\textbf{Failure} & \textbf{Pot.Div} & \textbf{Symptom} \\ + %\textbf{scenario} & \textbf{Effect} & \textbf{Description} \\ + \textbf{Fault} & \textbf{Pot.Div} & \textbf{Derived Component} \\ % \textbf{Symptom} \\ \textbf{Mode} & \textbf{Effect} & \textbf{Failure modes} \\ %\textbf{Description} \\ % R & wire & res + & res - & description @@ -632,19 +638,21 @@ we name this \textbf{PD}. This {\dc} will have two failure modes. We use the symbol $\derivec$ to represent the process of taking the analysed {\fg} and creating from it a {\dc}. -%The creation of the {\dc} \textbf{PD} isrepresented in figure~\ref{fig:dc1}. +The creation of the {\dc} \textbf{PD} is represented as a +hierarchy diagram in figure~\ref{fig:dc1}. We represent the {\dc} \textbf{PD}, as a DAG in figure \ref{fig:dc1dag}. %We could represent it algebraically thus: $ \derivec(PotDiv) = -% FUCKING HELL THIS IS REMOVED TOO : CUNTS -% \begin{figure}[h+] -% \centering -% \includegraphics[width=200pt,keepaspectratio=true]{./CH4_FMMD/dc1.png} %%% Where the f**king hell is this file ????? in an old paper even in the SYSSAFE2011 -% % dc1.jpg: 430x619 pixel, 72dpi, 15.17x21.84 cm, bb=0 0 430 619 -% \caption{From functional group to derived component} -% \label{fig:dc1} -% \end{figure} +% FUCKING HELL THIS IS to be REMOVED TOO : CUNTS +\begin{figure}[h+] + \centering + \includegraphics[width=200pt,keepaspectratio=true]{./CH4_FMMD/dc1.png} + % dc1.jpg: 430x619 pixel, 72dpi, 15.17x21.84 cm, bb=0 0 430 619 + \caption{From functional group to derived component, a hierarchical diagram showing how the {\fg} is analysed using the $\derivec$ + manual process and from this the {\dc} is created.} + \label{fig:dc1} +\end{figure} % We can now represent the potential divider as a {\dc}. @@ -674,14 +682,15 @@ We represent the {\dc} \textbf{PD}, as a DAG in figure \ref{fig:dc1dag}. % The derived component is defined by its failure modes and % the functional group used to derive it. % %We can consider this an an orthogonal WHAT???? Group ???? Collection ???? -% We now have a {\dc} model for a generic potential divider, and can use it -% as a building block for other {\fgs} in the same way as we used the base components $R1$ and $R2$. +We now have a {\dc} model for a generic potential divider, and can use it +as a building block for other {\fgs} in the same way as we used the base components $R1$ and $R2$. %\clearpage -%\paragraph{Failure Mode Analysis of the OP-AMP} +\paragraph{Failure Mode Analysis of a generic op-amp} -Let use now consider the op-amp as a {\bc}. According to +\clearpage +Let us now consider the op-amp as a {\bc}. According to FMD-91~\cite{fmd91}[3-116] an op amp may have the following failure modes (with assigned probabilities): latch-up(12.5\%), latch-down(6\%), no-operation(31.3\%), low~slew~rate(50\%). \nocite{mil1991} @@ -745,6 +754,11 @@ The two components in this new {\fg} have failure modes. \centering % used for centering table \begin{tabular}{||l|c|c|l||} \hline \hline +%% FUCKING HATE HAVING TO REMOVE THE TERM FAILURE SCENARIO --- whats is this the fucking +%%childrens version +%\textbf{Failure} & \textbf{Amplifier} & \textbf{Derived component} \\ %Symptom} \\ +% \textbf{Scenario} & \textbf{Effect} & \textbf{Failure Modes} \\ %Description} \\ +%% \textbf{Fault} & \textbf{Amplifier} & \textbf{Derived component} \\ %Symptom} \\ \textbf{Mode} & \textbf{Effect} & \textbf{Failure Modes} \\ %Description} \\ % R & wire & res + & res - & description @@ -903,24 +917,25 @@ The two components in this new {\fg} have failure modes. %amplification characteristics from FS2 and FS6 can be considered as low output from the OPAMP for the application %in hand (say milli-volt signal amplification). -% For this amplifier configuration we have three {\dc} failure modes; {\em AMP\_High, AMP\_Low, LowPass}. % see figure~\ref{fig:fgampb}. -% This model now has two stages of analysis hierarchy, -% as represented in figure~\ref{fig:dc2}. -% +For this amplifier configuration we have three {\dc} failure modes; {\em AMP\_High, AMP\_Low, LowPass}. % see figure~\ref{fig:fgampb}. +This model now has two stages of analysis hierarchy, +as represented in figure~\ref{fig:dc2}. + From the analysis in table \ref{tbl:ampfmea1} we can create the {\dc} {\em NONINVAMP}, which represents the failure mode behaviour of the non-inverting amplifier. -% \begin{figure}[h] -% \centering -% \includegraphics[width=225pt]{./CH4_FMMD/dc2.png} -% % dc2.png: 635x778 pixel, 72dpi, 22.40x27.45 cm, bb=0 0 635 778 -% \caption{Hierarchy representing the two stage FMMD analysis of the non-inverting amplifier} -% \label{fig:dc2} -% \end{figure} +\begin{figure}[h] + \centering + \includegraphics[width=225pt]{./CH4_FMMD/dc2.png} + % dc2.png: 635x778 pixel, 72dpi, 22.40x27.45 cm, bb=0 0 635 778 + \caption{Hierarchy representing the two stage FMMD analysis + (i.e. two `$\derivec$' processes taking {\fgs} and creating {\dcs}) for the non-inverting amplifier} + \label{fig:dc2} +\end{figure} -We can represent the hierarchy as an Euler diagram as well, where the curves -define the components and {\dcs} used to form {\fgs}, see figure~\ref{fig:eulerfmmd}. +We can also represent the hierarchy as an Euler diagram, where the curves +define the components and {\dcs} used to form the INVAMP model, see figure~\ref{fig:eulerfmmd}. \begin{figure}[h] \centering @@ -1023,8 +1038,9 @@ Component & A building block, this may be a {\bc} or a {\dc}. \\%or manufacture %this would be both a {\em{\dc}} and a {\fg}. \\ %{\em Constraint} & This object must have a defined set of failure~modes. \\ \hline - -Failure mode & A way in which a component can fail. \\ \hline +%%A part failure mode is the way in which a component fails "functionally" on component level. Often a part has only a few failure modes. +Failure mode & A failure mode~\cite{sccs}[p.8] is the way in which a component may fail functionally (i.e. the way in which it can fail to perform +its intended function). A component will typically have few failure modes. \\ \hline Functional Grouping & A collection of components with a functional purpose. @@ -1039,10 +1055,12 @@ Derived Component & A theoretical component, created to represent the failure {\em Constraint} & This object must have a defined set of failure~modes. \\ \hline +% UNITARY STATE NOT DISCUSSED HERE NOW...... +% Unitary State & A component with `unitary~state' failure modes, means that it cannot fail +% with more than one of its failure modes at a time.\\ \hline -Unitary State & A component with `unitary~state' failure modes, means that it cannot fail -with more than one of its failure modes at a time.\\ \hline +%%%% TOLD TO REMOVE THIS BUT FUCKING HATE TO HAVE TO DO IT % Failure Scenario & A single failure mode (or a combination), used to % determine failure mode effects on a {\fg}. \\ @@ -1054,7 +1072,7 @@ with more than one of its failure modes at a time.\\ \hline \end{table} -\subsection{Parts, Components and Base Components.} +\paragraph{A discussion on the terms Parts, Components and Base Components.} A component is anything we use to build a %a product or system. It could be something quite complicated