# Design and Experimental Study of a Down-Drive Piezoelectric High-Frequency Fatigue Testing Machine
## 4 Trial Tests
### Test System Construction and Test Methods
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Part Number** & **Part Name** & **Dimensional Parameters** &
\begin{tabular}{c} **Parameter Value** \\ **(mm)** \\ \end{tabular} \\ \hline
6 & Backbone & \
\begin{tabular}{c} Length \\ Width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 200 \\ 35 \\ 20 \\ \end{tabular} \\ \hline
7 & Screw & Large diameter & M10 \\ \hline
8 & Load handle & Outer diameter & \(\phi\)8 \\ \hline
9 & Sensor fixing plate & \
\begin{tabular}{c} Length \\ Width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 60 \\ 30 \\ 15 \\ \end{tabular} \\ \hline
10 & Transducers & \
\begin{tabular}{c} Middle diameter \\ Diameter on both sides \\ High degree \\ \end{tabular} &
\begin{tabular}{c} \(\phi\)20 \\ \(\phi\)16 \\ 22 \\ \end{tabular} \\ \hline
11 & \begin{tabular}{c} Transducer lower \\ connection plate \\ \end{tabular} & \
\begin{tabular}{c} Length \\ Width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 35 \\ 30 \\ 15 \\ \end{tabular} \\ \hline
12 & \begin{tabular}{c} Fixture fixing plate \\ \end{tabular} & \
\begin{tabular}{c} Length \\ Width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 35 \\ 30 \\ 15 \\ \end{tabular} \\ \hline
13 & Fixture & \
\begin{tabular}{c} Width \\ Specimen clamping range \\ \end{tabular} &
\begin{tabular}{c} 15 \\ \(\leq\)4 \\ \end{tabular} \\ \hline
14 & Specimen & \
\begin{tabular}{c} Length \\ Width on both sides \\ Middle width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 55 \\ 10 \\ 0.8 \\ 0.5 \\ \end{tabular} \\ \hline
15 & Vibration plate & \
\begin{tabular}{c} Length \\ Width \\ Thickness on both sides \\ Thickness in the middle \\ \end{tabular} &
\begin{tabular}{c} 53 \\ 30 \\ 7 \\ 13 \\ \end{tabular} \\ \hline
16 & Elastic ring & \
\begin{tabular}{c} Length \\ Width \\ Thickness \\ \end{tabular} &
\begin{tabular}{c} 94 \\ 8 \\ 5 \\ \end{tabular} \\ \hline
17 & Telegraph rod & \
\begin{tabular}{c} Length \\ Calibre \\ Head diameter \\ \end{tabular} &
\begin{tabular}{c} 94 \\ 8 \\ 5 \\ \end{tabular} \\ \hline
18 & \begin{tabular}{c} Mass of \\ counterweights \\ \end{tabular} & \
\begin{tabular}{c} Outer diameter \\ Inside diameter \\ Inside diameter \\ Thickness on all sides \\ Thickness in the middle \\ \end{tabular} &
\begin{tabular}{c} \(\phi\)90 \\ 570 \\ 8 \\ \end{tabular} \\ \hline
20 & Piezoelectric & \
\begin{tabular}{c} Outer diameter \\ Inside diameter \\ Thickness on all sides \\ Thickness in the middle \\ \end{tabular} &
\begin{tabular}{c} \(\phi\)90 \\ 8 \\ \end{tabular} \\ \hline
21 & \begin{tabular}{c} Circle in midstream \\ \end{tabular} & \
\begin{tabular}{c} Outer diameter \\ Inside diameter \\ Thickness on all sides \\ Thickness at centre \\ \end{tabular} &
\begin{tabular}{c} \(\phi\)90 \\ 570 \\ 10 \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: _Cont._Prior to the start of the test, the specimen is clamped between the upper and lower fixtures, a suitable initial static load is applied to the specimen using the preset load adjustment mechanism, and the static load is maintained using the upper locking bolt. A precision impedance analyser is used to determine the intrinsic frequency of the system at this point, and an alternating voltage is applied to the piezoelectric vibrator at the intrinsic frequency. After continuously increasing the RMS value of the driving voltage, the transducer is utilized to determine the alternating load applied to the specimen at different voltages and recorded in real time using the VI acquisition software; The characteristics and output performance of the fatigue testing machine system are investigated by means of specimens of different stiffness.