Add inkscape directory

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Thomas Dehaeze 2025-04-18 17:49:05 +02:00
parent 1f82647b2d
commit 54bc6d8403
9 changed files with 29 additions and 76 deletions

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#!/bin/bash
# Directory containing SVG files
INPUT_DIR="."
# Loop through all SVG files in the directory
for svg_file in "$INPUT_DIR"/*.svg; do
# Check if there are SVG files in the directory
if [ -f "$svg_file" ]; then
# Output PDF file name
pdf_file="../${svg_file%.svg}.pdf"
png_file="../${svg_file%.svg}"
# Convert SVG to PDF using Inkscape
inkscape "$svg_file" --export-filename="$pdf_file" && \
pdftocairo -png -singlefile -cropbox "$pdf_file" "$png_file"
fi
done

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@ -266,7 +266,7 @@ end
data2orgtable(1e6*apa_d', {'APA 1', 'APA 2', 'APA 3', 'APA 4', 'APA 5', 'APA 6', 'APA 7'}, {'*Flatness* $[\mu m]$'}, ' %.1f '); data2orgtable(1e6*apa_d', {'APA 1', 'APA 2', 'APA 3', 'APA 4', 'APA 5', 'APA 6', 'APA 7'}, {'*Flatness* $[\mu m]$'}, ' %.1f ');
#+end_src #+end_src
#+attr_latex: :options [b]{0.49\linewidth} #+attr_latex: :options [b]{0.48\linewidth}
#+begin_minipage #+begin_minipage
#+name: fig:test_apa_flatness_setup #+name: fig:test_apa_flatness_setup
#+attr_latex: :width 0.7\linewidth :float nil #+attr_latex: :width 0.7\linewidth :float nil
@ -274,7 +274,7 @@ data2orgtable(1e6*apa_d', {'APA 1', 'APA 2', 'APA 3', 'APA 4', 'APA 5', 'APA 6',
[[file:figs/test_apa_flatness_setup.png]] [[file:figs/test_apa_flatness_setup.png]]
#+end_minipage #+end_minipage
\hfill \hfill
#+attr_latex: :options [b]{0.49\linewidth} #+attr_latex: :options [b]{0.48\linewidth}
#+begin_minipage #+begin_minipage
#+name: tab:test_apa_flatness_meas #+name: tab:test_apa_flatness_meas
#+attr_latex: :environment tabularx :width 0.6\linewidth :align Xc #+attr_latex: :environment tabularx :width 0.6\linewidth :align Xc

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@ -1,4 +1,4 @@
% Created 2025-02-12 Wed 09:53 % Created 2025-04-03 Thu 22:11
% Intended LaTeX compiler: pdflatex % Intended LaTeX compiler: pdflatex
\documentclass[a4paper, 10pt, DIV=12, parskip=full, bibliography=totoc]{scrreprt} \documentclass[a4paper, 10pt, DIV=12, parskip=full, bibliography=totoc]{scrreprt}
@ -27,13 +27,6 @@
\author{Dehaeze Thomas} \author{Dehaeze Thomas}
\date{\today} \date{\today}
\title{Test Bench - Amplified Piezoelectric Actuator} \title{Test Bench - Amplified Piezoelectric Actuator}
\hypersetup{
pdfauthor={Dehaeze Thomas},
pdftitle={Test Bench - Amplified Piezoelectric Actuator},
pdfkeywords={},
pdfsubject={},
pdfcreator={Emacs 29.4 (Org mode 9.6)},
pdflang={English}}
\usepackage{biblatex} \usepackage{biblatex}
\begin{document} \begin{document}
@ -42,7 +35,6 @@
\tableofcontents \tableofcontents
\clearpage \clearpage
In this chapter, the goal is to ensure that the received APA300ML (shown in Figure \ref{fig:test_apa_received}) are complying with the requirements and that the dynamical models of the actuator accurately represent its dynamics. In this chapter, the goal is to ensure that the received APA300ML (shown in Figure \ref{fig:test_apa_received}) are complying with the requirements and that the dynamical models of the actuator accurately represent its dynamics.
In section \ref{sec:test_apa_basic_meas}, the mechanical tolerances of the APA300ML interfaces are checked together with the electrical properties of the piezoelectric stacks and the achievable stroke. In section \ref{sec:test_apa_basic_meas}, the mechanical tolerances of the APA300ML interfaces are checked together with the electrical properties of the piezoelectric stacks and the achievable stroke.
@ -64,16 +56,14 @@ This more complex model also captures well capture the axial dynamics of the APA
\includegraphics[scale=1,width=0.7\linewidth]{figs/test_apa_received.jpg} \includegraphics[scale=1,width=0.7\linewidth]{figs/test_apa_received.jpg}
\caption{\label{fig:test_apa_received}Picture of 5 out of the 7 received APA300ML} \caption{\label{fig:test_apa_received}Picture of 5 out of the 7 received APA300ML}
\end{figure} \end{figure}
\chapter{First Basic Measurements} \chapter{First Basic Measurements}
\label{sec:test_apa_basic_meas} \label{sec:test_apa_basic_meas}
Before measuring the dynamical characteristics of the APA300ML, simple measurements are performed. Before measuring the dynamical characteristics of the APA300ML, simple measurements are performed.
First, the tolerances (especially flatness) of the mechanical interfaces are checked in Section \ref{ssec:test_apa_geometrical_measurements}. First, the tolerances (especially flatness) of the mechanical interfaces are checked in Section \ref{ssec:test_apa_geometrical_measurements}.
Then, the capacitance of the piezoelectric stacks is measured in Section \ref{ssec:test_apa_electrical_measurements}. Then, the capacitance of the piezoelectric stacks is measured in Section \ref{ssec:test_apa_electrical_measurements}.
The achievable stroke of the APA300ML is measured using a displacement probe in Section \ref{ssec:test_apa_stroke_measurements}. The achievable stroke of the APA300ML is measured using a displacement probe in Section \ref{ssec:test_apa_stroke_measurements}.
Finally, in Section \ref{ssec:test_apa_spurious_resonances}, the flexible modes of the APA are measured and compared with a finite element model. Finally, in Section \ref{ssec:test_apa_spurious_resonances}, the flexible modes of the APA are measured and compared with a finite element model.
\section{Geometrical Measurements} \section{Geometrical Measurements}
\label{ssec:test_apa_geometrical_measurements} \label{ssec:test_apa_geometrical_measurements}
@ -82,14 +72,14 @@ As shown in Figure \ref{fig:test_apa_flatness_setup}, the APA is fixed to a clam
From the X-Y-Z coordinates of the measured eight points, the flatness is estimated by best fitting\footnote{The Matlab \texttt{fminsearch} command is used to fit the plane} a plane through all the points. From the X-Y-Z coordinates of the measured eight points, the flatness is estimated by best fitting\footnote{The Matlab \texttt{fminsearch} command is used to fit the plane} a plane through all the points.
The measured flatness values, summarized in Table \ref{tab:test_apa_flatness_meas}, are within the specifications. The measured flatness values, summarized in Table \ref{tab:test_apa_flatness_meas}, are within the specifications.
\begin{minipage}[b]{0.49\linewidth} \begin{minipage}[b]{0.48\linewidth}
\begin{center} \begin{center}
\includegraphics[scale=1,width=0.7\linewidth]{figs/test_apa_flatness_setup.png} \includegraphics[scale=1,width=0.7\linewidth]{figs/test_apa_flatness_setup.png}
\captionof{figure}{\label{fig:test_apa_flatness_setup}Measurement setup for flatness estimation} \captionof{figure}{\label{fig:test_apa_flatness_setup}Measurement setup for flatness estimation}
\end{center} \end{center}
\end{minipage} \end{minipage}
\hfill \hfill
\begin{minipage}[b]{0.49\linewidth} \begin{minipage}[b]{0.48\linewidth}
\begin{center} \begin{center}
\begin{tabularx}{0.6\linewidth}{Xc} \begin{tabularx}{0.6\linewidth}{Xc}
\toprule \toprule
@ -108,7 +98,6 @@ APA 7 & 18.7\\
\end{center} \end{center}
\end{minipage} \end{minipage}
\section{Electrical Measurements} \section{Electrical Measurements}
\label{ssec:test_apa_electrical_measurements} \label{ssec:test_apa_electrical_measurements}
@ -149,7 +138,6 @@ APA 7 & 4.85 & 9.85\\
\end{center} \end{center}
\end{minipage} \end{minipage}
\section{Stroke and Hysteresis Measurement} \section{Stroke and Hysteresis Measurement}
\label{ssec:test_apa_stroke_measurements} \label{ssec:test_apa_stroke_measurements}
@ -190,7 +178,6 @@ From now on, only the six remaining amplified piezoelectric actuators that behav
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_stroke}Generated voltage across the two piezoelectric stack actuators to estimate the stroke of the APA300ML (\subref{fig:test_apa_stroke_voltage}). Measured displacement as a function of applied voltage (\subref{fig:test_apa_stroke_hysteresis})} \caption{\label{fig:test_apa_stroke}Generated voltage across the two piezoelectric stack actuators to estimate the stroke of the APA300ML (\subref{fig:test_apa_stroke_voltage}). Measured displacement as a function of applied voltage (\subref{fig:test_apa_stroke_hysteresis})}
\end{figure} \end{figure}
\section{Flexible Mode Measurement} \section{Flexible Mode Measurement}
\label{ssec:test_apa_spurious_resonances} \label{ssec:test_apa_spurious_resonances}
@ -251,7 +238,6 @@ Another explanation is the shape difference between the manufactured APA300ML an
\includegraphics[scale=1]{figs/test_apa_meas_freq_compare.png} \includegraphics[scale=1]{figs/test_apa_meas_freq_compare.png}
\caption{\label{fig:test_apa_meas_freq_compare}Frequency response functions for the two tests using the instrumented hammer and the laser vibrometer. The Y-bending mode is measured at \(280\,\text{Hz}\) and the X-bending mode at \(412\,\text{Hz}\)} \caption{\label{fig:test_apa_meas_freq_compare}Frequency response functions for the two tests using the instrumented hammer and the laser vibrometer. The Y-bending mode is measured at \(280\,\text{Hz}\) and the X-bending mode at \(412\,\text{Hz}\)}
\end{figure} \end{figure}
\chapter{Dynamical measurements} \chapter{Dynamical measurements}
\label{sec:test_apa_dynamics} \label{sec:test_apa_dynamics}
After the measurements on the APA were performed in Section \ref{sec:test_apa_basic_meas}, a new test bench was used to better characterize the dynamics of the APA300ML. After the measurements on the APA were performed in Section \ref{sec:test_apa_basic_meas}, a new test bench was used to better characterize the dynamics of the APA300ML.
@ -300,7 +286,6 @@ This is the typical behavior expected from a PZT stack actuator, where the hyste
\includegraphics[scale=1]{figs/test_apa_meas_hysteresis.png} \includegraphics[scale=1]{figs/test_apa_meas_hysteresis.png}
\caption{\label{fig:test_apa_meas_hysteresis}Displacement as a function of applied voltage for multiple excitation amplitudes} \caption{\label{fig:test_apa_meas_hysteresis}Displacement as a function of applied voltage for multiple excitation amplitudes}
\end{figure} \end{figure}
\section{Axial stiffness} \section{Axial stiffness}
\label{ssec:test_apa_stiffness} \label{ssec:test_apa_stiffness}
@ -362,7 +347,6 @@ To estimate this effect for the APA300ML, its stiffness is estimated using the `
\end{itemize} \end{itemize}
The open-circuit stiffness is estimated at \(k_{\text{oc}} \approx 2.3\,N/\mu m\) while the closed-circuit stiffness \(k_{\text{sc}} \approx 1.7\,N/\mu m\). The open-circuit stiffness is estimated at \(k_{\text{oc}} \approx 2.3\,N/\mu m\) while the closed-circuit stiffness \(k_{\text{sc}} \approx 1.7\,N/\mu m\).
\section{Dynamics} \section{Dynamics}
\label{ssec:test_apa_meas_dynamics} \label{ssec:test_apa_meas_dynamics}
@ -408,7 +392,6 @@ All the identified dynamics of the six APA300ML (both when looking at the encode
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_frf_dynamics}Measured frequency response function from generated voltage \(u\) to the encoder displacement \(d_e\) (\subref{fig:test_apa_frf_encoder}) and to the force sensor voltage \(V_s\) (\subref{fig:test_apa_frf_force}) for the six APA300ML} \caption{\label{fig:test_apa_frf_dynamics}Measured frequency response function from generated voltage \(u\) to the encoder displacement \(d_e\) (\subref{fig:test_apa_frf_encoder}) and to the force sensor voltage \(V_s\) (\subref{fig:test_apa_frf_force}) for the six APA300ML}
\end{figure} \end{figure}
\section{Non Minimum Phase Zero?} \section{Non Minimum Phase Zero?}
\label{ssec:test_apa_non_minimum_phase} \label{ssec:test_apa_non_minimum_phase}
@ -437,8 +420,6 @@ However, this is not so important here because the zero is lightly damped (i.e.
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_non_minimum_phase}Measurement of the anti-resonance found in the transfer function from \(u\) to \(V_s\). The coherence (\subref{fig:test_apa_non_minimum_phase_coherence}) is quite good around the anti-resonance frequency. The phase (\subref{fig:test_apa_non_minimum_phase_zoom}) shoes a non-minimum phase behavior.} \caption{\label{fig:test_apa_non_minimum_phase}Measurement of the anti-resonance found in the transfer function from \(u\) to \(V_s\). The coherence (\subref{fig:test_apa_non_minimum_phase_coherence}) is quite good around the anti-resonance frequency. The phase (\subref{fig:test_apa_non_minimum_phase_zoom}) shoes a non-minimum phase behavior.}
\end{figure} \end{figure}
\section{Effect of the resistor on the IFF Plant} \section{Effect of the resistor on the IFF Plant}
\label{ssec:test_apa_resistance_sensor_stack} \label{ssec:test_apa_resistance_sensor_stack}
@ -454,7 +435,6 @@ It is confirmed that the added resistor has the effect of adding a high-pass fil
\includegraphics[scale=1]{figs/test_apa_effect_resistance.png} \includegraphics[scale=1]{figs/test_apa_effect_resistance.png}
\caption{\label{fig:test_apa_effect_resistance}Transfer function from \(u\) to \(V_s\) with and without the resistor \(R\) in parallel with the piezoelectric stack used as the force sensor} \caption{\label{fig:test_apa_effect_resistance}Transfer function from \(u\) to \(V_s\) with and without the resistor \(R\) in parallel with the piezoelectric stack used as the force sensor}
\end{figure} \end{figure}
\section{Integral Force Feedback} \section{Integral Force Feedback}
\label{ssec:test_apa_iff_locus} \label{ssec:test_apa_iff_locus}
@ -513,10 +493,9 @@ The two obtained root loci are compared in Figure \ref{fig:test_apa_iff_root_loc
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_iff}Experimental results of applying Integral Force Feedback to the APA300ML. Obtained damped plant (\subref{fig:test_apa_identified_damped_plants}) and Root Locus (\subref{fig:test_apa_iff_root_locus}) corresponding to the implemented IFF controller \eqref{eq:test_apa_Kiff_formula}} \caption{\label{fig:test_apa_iff}Experimental results of applying Integral Force Feedback to the APA300ML. Obtained damped plant (\subref{fig:test_apa_identified_damped_plants}) and Root Locus (\subref{fig:test_apa_iff_root_locus}) corresponding to the implemented IFF controller \eqref{eq:test_apa_Kiff_formula}}
\end{figure} \end{figure}
\chapter{APA300ML - 2 degrees-of-freedom Model} \chapter{APA300ML - 2 degrees-of-freedom Model}
\label{sec:test_apa_model_2dof} \label{sec:test_apa_model_2dof}
In this section, a multi-body model (Figure \ref{fig:test_apa_bench_model}) of the measurement bench is used to tune the two degrees-of-freedom model of the APA using the measured frequency response functions. In this section, a multi-body model (Figure \ref{fig:test_apa_bench_model}) of the measurement bench is used to tune the two degrees-of-freedom model of the APA using the measured frequency response functions.
This two degrees-of-freedom model is developed to accurately represent the APA300ML dynamics while having low complexity and a low number of associated states. This two degrees-of-freedom model is developed to accurately represent the APA300ML dynamics while having low complexity and a low number of associated states.
@ -527,8 +506,7 @@ After the model is presented, the procedure for tuning the model is described, a
\includegraphics[scale=1,width=0.8\linewidth]{figs/test_apa_bench_model.png} \includegraphics[scale=1,width=0.8\linewidth]{figs/test_apa_bench_model.png}
\caption{\label{fig:test_apa_bench_model}Screenshot of the multi-body model} \caption{\label{fig:test_apa_bench_model}Screenshot of the multi-body model}
\end{figure} \end{figure}
\subsubsection{Two degrees-of-freedom APA Model}
\paragraph{Two degrees-of-freedom APA Model}
The model of the amplified piezoelectric actuator is shown in Figure \ref{fig:test_apa_2dof_model}. The model of the amplified piezoelectric actuator is shown in Figure \ref{fig:test_apa_2dof_model}.
It can be decomposed into three components: It can be decomposed into three components:
@ -553,7 +531,6 @@ Such a simple model has some limitations:
\includegraphics[scale=1]{figs/test_apa_2dof_model.png} \includegraphics[scale=1]{figs/test_apa_2dof_model.png}
\caption{\label{fig:test_apa_2dof_model}Schematic of the two degrees-of-freedom model of the APA300ML, adapted from \cite{souleille18_concep_activ_mount_space_applic}} \caption{\label{fig:test_apa_2dof_model}Schematic of the two degrees-of-freedom model of the APA300ML, adapted from \cite{souleille18_concep_activ_mount_space_applic}}
\end{figure} \end{figure}
9 parameters (\(m\), \(k_1\), \(c_1\), \(k_e\), \(c_e\), \(k_a\), \(c_a\), \(g_s\) and \(g_a\)) have to be tuned such that the dynamics of the model (Figure \ref{fig:test_apa_2dof_model_simscape}) well represents the identified dynamics in Section \ref{sec:test_apa_dynamics}. 9 parameters (\(m\), \(k_1\), \(c_1\), \(k_e\), \(c_e\), \(k_a\), \(c_a\), \(g_s\) and \(g_a\)) have to be tuned such that the dynamics of the model (Figure \ref{fig:test_apa_2dof_model_simscape}) well represents the identified dynamics in Section \ref{sec:test_apa_dynamics}.
\begin{figure}[htbp] \begin{figure}[htbp]
@ -609,7 +586,6 @@ The obtained parameters of the model shown in Figure \ref{fig:test_apa_2dof_mode
\caption{\label{tab:test_apa_2dof_parameters}Summary of the obtained parameters for the 2 DoF APA300ML model} \caption{\label{tab:test_apa_2dof_parameters}Summary of the obtained parameters for the 2 DoF APA300ML model}
\end{table} \end{table}
The dynamics of the two degrees-of-freedom model of the APA300ML are extracted using optimized parameters (listed in Table \ref{tab:test_apa_2dof_parameters}) from the multi-body model. The dynamics of the two degrees-of-freedom model of the APA300ML are extracted using optimized parameters (listed in Table \ref{tab:test_apa_2dof_parameters}) from the multi-body model.
This is compared with the experimental data in Figure \ref{fig:test_apa_2dof_comp_frf}. This is compared with the experimental data in Figure \ref{fig:test_apa_2dof_comp_frf}.
A good match can be observed between the model and the experimental data, both for the encoder (Figure \ref{fig:test_apa_2dof_comp_frf_enc}) and for the force sensor (Figure \ref{fig:test_apa_2dof_comp_frf_force}). A good match can be observed between the model and the experimental data, both for the encoder (Figure \ref{fig:test_apa_2dof_comp_frf_enc}) and for the force sensor (Figure \ref{fig:test_apa_2dof_comp_frf_force}).
@ -630,9 +606,9 @@ This indicates that this model represents well the axial dynamics of the APA300M
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_2dof_comp_frf}Comparison of the measured frequency response functions and the identified dynamics from the 2DoF model of the APA300ML. Both for the dynamics from \(u\) to \(d_e\) (\subref{fig:test_apa_2dof_comp_frf_enc}) (\subref{fig:test_apa_2dof_comp_frf_force}) and from \(u\) to \(V_s\) (\subref{fig:test_apa_2dof_comp_frf_force})} \caption{\label{fig:test_apa_2dof_comp_frf}Comparison of the measured frequency response functions and the identified dynamics from the 2DoF model of the APA300ML. Both for the dynamics from \(u\) to \(d_e\) (\subref{fig:test_apa_2dof_comp_frf_enc}) (\subref{fig:test_apa_2dof_comp_frf_force}) and from \(u\) to \(V_s\) (\subref{fig:test_apa_2dof_comp_frf_force})}
\end{figure} \end{figure}
\chapter{APA300ML - Super Element} \chapter{APA300ML - Super Element}
\label{sec:test_apa_model_flexible} \label{sec:test_apa_model_flexible}
In this section, a \emph{super element} of the APA300ML is computed using a finite element software\footnote{Ansys\textsuperscript{\textregistered} was used}. In this section, a \emph{super element} of the APA300ML is computed using a finite element software\footnote{Ansys\textsuperscript{\textregistered} was used}.
It is then imported into multi-body (in the form of a stiffness matrix and a mass matrix) and included in the same model that was used in \ref{sec:test_apa_model_2dof}. It is then imported into multi-body (in the form of a stiffness matrix and a mass matrix) and included in the same model that was used in \ref{sec:test_apa_model_2dof}.
This procedure is illustrated in Figure \ref{fig:test_apa_super_element_simscape}. This procedure is illustrated in Figure \ref{fig:test_apa_super_element_simscape}.
@ -648,50 +624,12 @@ Finally, two \emph{remote points} (\texttt{4} and \texttt{5}) are located across
\includegraphics[scale=1,width=1.0\linewidth]{figs/test_apa_super_element_simscape.png} \includegraphics[scale=1,width=1.0\linewidth]{figs/test_apa_super_element_simscape.png}
\caption{\label{fig:test_apa_super_element_simscape}Finite Element Model of the APA300ML with ``remotes points'' on the left. Simscape model with included ``Reduced Order Flexible Solid'' on the right.} \caption{\label{fig:test_apa_super_element_simscape}Finite Element Model of the APA300ML with ``remotes points'' on the left. Simscape model with included ``Reduced Order Flexible Solid'' on the right.}
\end{figure} \end{figure}
\subsubsection{Identification of the Actuator and Sensor constants}
\paragraph{Identification of the Actuator and Sensor constants}
Once the APA300ML \emph{super element} is included in the multi-body model, the transfer function from \(F_a\) to \(d_L\) and \(d_e\) can be extracted. Once the APA300ML \emph{super element} is included in the multi-body model, the transfer function from \(F_a\) to \(d_L\) and \(d_e\) can be extracted.
The gains \(g_a\) and \(g_s\) are then tuned such that the gains of the transfer functions match the identified ones. The gains \(g_a\) and \(g_s\) are then tuned such that the gains of the transfer functions match the identified ones.
By doing so, \(g_s = 4.9\,V/\mu m\) and \(g_a = 23.2\,N/V\) are obtained. By doing so, \(g_s = 4.9\,V/\mu m\) and \(g_a = 23.2\,N/V\) are obtained.
\subsubsection{Comparison of the obtained dynamics}
To ensure that the sensitivities \(g_a\) and \(g_s\) are physically valid, it is possible to estimate them from the physical properties of the piezoelectric stack material.
From \cite[p. 123]{fleming14_desig_model_contr_nanop_system}, the relation between relative displacement \(d_L\) of the sensor stack and generated voltage \(V_s\) is given by \eqref{eq:test_apa_piezo_strain_to_voltage} and from \cite{fleming10_integ_strain_force_feedb_high} the relation between the force \(F_a\) and the applied voltage \(V_a\) is given by \eqref{eq:test_apa_piezo_voltage_to_force}.
\begin{subequations}
\begin{align}
V_s &= \underbrace{\frac{d_{33}}{\epsilon^T s^D n}}_{g_s} d_L \label{eq:test_apa_piezo_strain_to_voltage} \\
F_a &= \underbrace{d_{33} n k_a}_{g_a} \cdot V_a, \quad k_a = \frac{c^{E} A}{L} \label{eq:test_apa_piezo_voltage_to_force}
\end{align}
\end{subequations}
Unfortunately, the manufacturer of the stack was not willing to share the piezoelectric material properties of the stack used in the APA300ML.
However, based on the available properties of the APA300ML stacks in the data-sheet, the soft Lead Zirconate Titanate ``THP5H'' from Thorlabs seemed to match quite well the observed properties.
The properties of this ``THP5H'' material used to compute \(g_a\) and \(g_s\) are listed in Table \ref{tab:test_apa_piezo_properties}.
From these parameters, \(g_s = 5.1\,V/\mu m\) and \(g_a = 26\,N/V\) were obtained, which are close to the constants identified using the experimentally identified transfer functions.
\begin{table}[htbp]
\centering
\begin{tabularx}{1\linewidth}{ccX}
\toprule
\textbf{Parameter} & \textbf{Value} & \textbf{Description}\\
\midrule
\(d_{33}\) & \(680 \cdot 10^{-12}\,m/V\) & Piezoelectric constant\\
\(\epsilon^{T}\) & \(4.0 \cdot 10^{-8}\,F/m\) & Permittivity under constant stress\\
\(s^{D}\) & \(21 \cdot 10^{-12}\,m^2/N\) & Elastic compliance understand constant electric displacement\\
\(c^{E}\) & \(48 \cdot 10^{9}\,N/m^2\) & Young's modulus of elasticity\\
\(L\) & \(20\,mm\) per stack & Length of the stack\\
\(A\) & \(10^{-4}\,m^2\) & Area of the piezoelectric stack\\
\(n\) & \(160\) per stack & Number of layers in the piezoelectric stack\\
\bottomrule
\end{tabularx}
\caption{\label{tab:test_apa_piezo_properties}Piezoelectric properties used for the estimation of the sensor and actuators sensitivities}
\end{table}
\paragraph{Comparison of the obtained dynamics}
The obtained dynamics using the \emph{super element} with the tuned ``sensor sensitivity'' and ``actuator sensitivity'' are compared with the experimentally identified frequency response functions in Figure \ref{fig:test_apa_super_element_comp_frf}. The obtained dynamics using the \emph{super element} with the tuned ``sensor sensitivity'' and ``actuator sensitivity'' are compared with the experimentally identified frequency response functions in Figure \ref{fig:test_apa_super_element_comp_frf}.
A good match between the model and the experimental results was observed. A good match between the model and the experimental results was observed.
@ -714,7 +652,6 @@ Using this simple test bench, it can be concluded that the \emph{super element}
\end{subfigure} \end{subfigure}
\caption{\label{fig:test_apa_super_element_comp_frf}Comparison of the measured frequency response functions and the identified dynamics from the finite element model of the APA300ML. Both for the dynamics from \(u\) to \(d_e\) (\subref{fig:test_apa_super_element_comp_frf_enc}) and from \(u\) to \(V_s\) (\subref{fig:test_apa_super_element_comp_frf_force})} \caption{\label{fig:test_apa_super_element_comp_frf}Comparison of the measured frequency response functions and the identified dynamics from the finite element model of the APA300ML. Both for the dynamics from \(u\) to \(d_e\) (\subref{fig:test_apa_super_element_comp_frf_enc}) and from \(u\) to \(V_s\) (\subref{fig:test_apa_super_element_comp_frf_force})}
\end{figure} \end{figure}
\chapter{Conclusion} \chapter{Conclusion}
\label{sec:test_apa_conclusion} \label{sec:test_apa_conclusion}
@ -737,8 +674,6 @@ Here, the \emph{super element} represents the dynamics of the APA300ML in all di
However, only the axial dynamics could be compared with the experimental results, yielding a good match. However, only the axial dynamics could be compared with the experimental results, yielding a good match.
The benefit of employing this model over the two degrees-of-freedom model is not immediately apparent due to its increased complexity and the larger number of model states involved. The benefit of employing this model over the two degrees-of-freedom model is not immediately apparent due to its increased complexity and the larger number of model states involved.
Nonetheless, the \emph{super element} model's value will become clear in subsequent sections, when its capacity to accurately model the APA300ML's flexibility across various directions will be important. Nonetheless, the \emph{super element} model's value will become clear in subsequent sections, when its capacity to accurately model the APA300ML's flexibility across various directions will be important.
\printbibliography[heading=bibintoc,title={Bibliography}] \printbibliography[heading=bibintoc,title={Bibliography}]
\printglossaries \printglossaries
\end{document} \end{document}