overleaf-AHEPaM/cau-ath-pla-0008_i1-0/margin.tex

\section{Margin Philosophy}
\label{sec:margin}
For all space mission related instruments developed by the \acs{ETPH} and throughout the design process, certain margins are applied to the various elements, which the planned instrument will later consist of. The process of applying margins is generally being performed in order to define the  maximum fluctuation range certain material or parts' parameters can take. Working with these maximum or minimum thresholds makes it possible to create the interacting components of an instrument, although it just being in a conceptual state. \newline

In the following section the term \textit{ECSS} refers to \textit{Table 5-1: Product categories according to heritage} of the
\textit{ECSS/ Space Engineering Verification document}\cite{ecss-e-st-10-02c}.

\subsection{Mass Margins}
\label{sec:mass-margins}

The following margins are applied to mass estimations, derived from EIDA-2656\cite{solo-eida}: The PI shall apply the following contingency factors due to uncertainty and/or
design maturity: 

\begin{itemize}
    \item $<=$5\% for “Off-The-Shelf” items \(ECSS   Category: A / B\) \newline OR \newline for manufatured/ machined parts which have successfully passed a relevant verifiction test.
    \item $<=$10\% for “Off-The-Shelf” items requiring minor modifications \(ECSS   Category: C\) \newline OR \newline in case of manufactured/ machined parts which have successfully been manufactured/ machined and where all related processes have been proven to deliver good repeated manufacturing accuracy. 
    \begin{itemize}
        \item Example: Chassis parts, which have been machined according to manufacturing specifications and can reliably be built again.
    \end{itemize}
    \item $<=$20\% for newly designed / developed items, or items requiring major modifications or re-design \(ECSS Category: D\) \newline OR \newline to all to be manufactured/ machined parts which are under design process and have not yet proven a reliable process workflow.
    \begin{itemize}
        \item Example: All chassis parts which are part of a CAD model, but have not yet been machined.
    \end{itemize}
\end{itemize}

Furthermore we implement EIDA-1906\cite{solo-eida} in our mass estimations: The PI shall ensure that the following margin philosophy for mass, power and
data rate nominal values vs. allocated values, are met:
\begin{itemize}
    \item 20\% margin at PDR
    \item 10\% margin at CDR 
\end{itemize}