# Development of a Drone's Vibration, Shock, and Atmospheric Profiles
## 3 Results and Discussion
### Shock  
For DJI Matrice 600 Pro, there was a total of 39 shock events recorded by the top data logger in the Y direction during the flight, with an averaged G-value of 5.57 \(\pm\) 0.9. The intensity of a given shock is characterized by its acceleration level (amplitude), and the length of time (duration) over which the shock takes place [27]. Shock events are either positive or negative because of the orientation of the impact event. No shock events were recorded in the X and Z directions. The Y direction is in line with the axis of the two arms (Figure 2). On the other hand, three shock events were detected by the data logger on the platform above the payload in the Z direction, its averaged G-value recorded was 6.40 \(\pm\) 0.9. No shocks were recorded in the X and Y directions by this data logger. The buffer between the motor and platform is effective in filtering out most shock events in the horizontal level caused by motors.  
For DJI Matrice 100, a total of 128 shock events in the Y direction were recorded by the data logger installed on the frame during the flight (Bottom data logger). The average shock value was 7.80 \(\pm\) 1.6. The top data logger recorded eight shock events in the Z direction. The averaged G-value was 6.16 \(\pm\) 0.5. There were no big major shocks recorded during the takeoff and landing for both drones in all three directions.  
Table 6 revealed some of the major shocks above the average and their SRS frequencies. The shock frequencies corresponding to the peak values for both drones are between 171.85 Hz to 182.67 Hz, indicating the same shock response frequencies related to the two-propeller rotations across the two drones.  
Figure 9: Vibration G\({}_{\text{rms}}\) histogram for DJI 100.  
Figure 10 shows continuous shocks in the Y direction recorded by the bottom data logger on the DJI Matrice 100. Figure 11 illustrates the SRS spectrum of the number 9 event in Figure 10. The 12.8 G in the Y direction occurred at 182.01 Hz, which could be the effect of the 2-blade propeller's structure frequency (Motor RPM)/30 Hz, originating from the motor shaft frequency 91 Hz, (Motor RPM)/60. These values suggest that the aforementioned shocks are likely caused by the throttle jumps of the drone operator pilot. The quadcopter frame where the bottom data logger was located, connects all four arms of the propellers and directly receives the shock from the propellers when the throttle jumps occurred, whereas the top data logger had relative minimal shocks due to its location in the center of the drone, furthest from the propellers.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{5}{c}{**DJI Matrice 600 Pro Shock Values above the Average**} \\ \hline
**Max. X** & **Max. Y** & **Max. Z** & **Location of Data Logger** & **SRS Frequency (Hz)** \\ \hline \(-\)3.20 & \(-\)7.04 & 3.84 & Top data logger & 171.85 \\ \(-\)3.20 & \(-\)6.40 & 3.20 & Top data logger & 171.85 \\ \(-\)3.20 & \(-\)7.04 & 3.84 & Top data logger & 182.01 \\ \(-\)3.20 & \(-\)6.40 & 3.84 & Top data logger & 182.01 \\ \hline \multicolumn{5}{c}{**DJI Matrice 100 Pro shock values above the average**} \\ \hline \(-\)2.56 & \(-\)12.80 & \(-\)3.20 & Bottom data logger & 182.67 \\ \(-\)2.56 & \(-\)12.16 & 3.20 & Bottom data logger & 182.01 \\ \(-\)4.48 & \(-\)14.08 & 3.84 & Bottom data logger & 171.85 \\ \(-\)4.48 & \(-\)10.88 & 3.84 & Bottom data logger & 182.01 \\ \(-\)3.20 & \(-\)10.88 & 3.84 & Bottom data logger & 182.01 \\ \(-\)3.84 & \(-\)10.24 & 3.84 & Bottom data logger & 182.01 \\ \(-\)3.20 & \(-\)11.52 & 3.84 & Bottom data logger & 171.85 \\ \(-\)3.20 & \(-\)10.24 & 3.84 & Bottom data logger & 182.01 \\ \(-\)3.84 & \(-\)10.24 & 3.84 & Bottom data logger & 136.61 \\ \hline \hline \end{tabular}
\end{table}
Table 6: Major shocks and their SRS frequencies.  
Figure 10: Exemplary shock data collected by the bottom data logger on the DJI Matrice 100.