conclusion

This commit is contained in:
Robin Clark 2011-03-30 11:35:48 +01:00
parent 0e887bb0fc
commit 2fecdb0771
2 changed files with 40 additions and 13 deletions

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@ -329,14 +329,31 @@ any new problems.
First let us look at the new transistor and resistor and First let us look at the new transistor and resistor and
treat these as a functional group. treat these as a functional group.
In our analysis of the failure modes we have to consider
both states of the transistor, ON and OFF. \begin{figure}[h]
\centering
\includegraphics[width=200pt,keepaspectratio=true]{./fmmd_design_aide/test_circuit.png}
% test_circuit.png: 239x144 pixel, 72dpi, 8.43x5.08 cm, bb=0 0 239 144
\caption{Test circuit functional group}
\label{fig:test_circuit}
\end{figure}
In our analysis of the failure modes we have to consider the operational
states of this circuit, which are
the transistor being switched ON and OFF.
\begin{figure}[h] \begin{figure}[h]
\centering \centering
\includegraphics[width=200pt,keepaspectratio=true]{./fmmd_design_aide/mv_opamp_circuit2.png} \includegraphics[width=200pt,keepaspectratio=true]{./fmmd_design_aide/mv_opamp_circuit2.png}
% mv_opamp_circuit2.png: 577x479 pixel, 72dpi, 20.35x16.90 cm, bb=0 0 577 479 % mv_opamp_circuit2.png: 577x479 pixel, 72dpi, 20.35x16.90 cm, bb=0 0 577 479
\caption{Amplifier with check circuit} \caption{Amplifier with check circuit addition}
\label{fig:mvamp2} \label{fig:mvamp2}
\end{figure} \end{figure}
@ -392,6 +409,13 @@ $\overline{TEST\_LINE}$ OFF & TC:4 $TR1$ ALWAYS OFF & resistance always adde
\label{tab:testaddition} \label{tab:testaddition}
\end{table} \end{table}
\subsection{Test Cases Analysis in detail} \subsection{Test Cases Analysis in detail}
The purpose of this circuit is to switch a resistance in when we want to test the circuit The purpose of this circuit is to switch a resistance in when we want to test the circuit
@ -452,19 +476,21 @@ As a symptom for this circuit, it means that there would be no test effect.
\subsection{conclusion of FMMD analysis on safety addition} \subsection{conclusion of FMMD analysis on safety addition}
This test circuit has from its four component failure modes,
3 failure symptoms $\{ NO TEST EFFECT, NO SYMPTOM, OPEN CIRCUIT \}$
For the FMMD analysis in table \ref{tab:testaddition} we have two failure modes for its derived component For the FMMD analysis in table \ref{tab:testaddition} we have two failure modes for its derived component
`no~test~effect' or `open~circuit'. `no~test~effect' or `open~circuit'. There
%~out~of~range'. $NO SYMPTOM$ failure mode is dormant, but will be revealed when the test~line changes state.
The next stage is to combine the two derived components we have made into The next stage is to combine the two derived components we have made into
a functional group. a higher level functional group, see figure \ref{fig:testable_mvamp}.
\section{FMMD Hierarchy, with milli-volt amp and safety addition} \section{FMMD Hierarchy, with milli-volt amp and safety addition}
The next stage is to take the two derived components We have created two derived components, the amplifier, and the test~circuit, we
and place them into a functional group. now place them into a new functional group.
We can now analyse this functional We can now analyse this functional
group w.r.t the failure modes in the two derived compoennts. group w.r.t the failure modes of the two derived components.
\begin{figure}[h] \begin{figure}[h]
\centering \centering

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@ -874,9 +874,10 @@ to all base component failure modes.
% %
PLD's can be used to model Mechanical, Electrical and Software PLD's can be used to model Mechanical, Electrical and Software
failure modes. More importantly the interfaces between these disciplines can be modelled failure modes. More importantly the interfaces between these disciplines can be modelled
seamlessly. The bottom-up nature of its associated methodology, Failure Mode Modular De-Composition (FMMD) seamlessly.
ensures that complete coverage of all base~component failures modes %
can be ensured. The bottom-up nature of its associated methodology, Failure Mode Modular De-Composition (FMMD)
ensures complete coverage of all base~component failures modes is possible.
% Elevator Pitch % Elevator Pitch
%\pagebreak[4] %\pagebreak[4]