# A Drone-Enabled Approach for Gas Leak Detection Using Optical Flow Analysis +
## 4 Experiments
### Experiment C: Drone-Based Inspection  
In this experiment, the main objective is to investigate the use of aerial platforms for gas leak detection and visually-enhancement of the gas emanation. Moreover, the experiment is used for the comparative analysis of candidate stabilization techniques. It is conducted in two sessions recorded by thermal and digital cameras as shown in Figure 5, providing a total of four sets of data, covering various scenarios that can be used in the analysis. The experimental setup involves a fire pit containing ignited dried trunks and woodchips. The ignited woods make smoke which simulates a scenario for further analysis. The details of the experiment are listed in Table 3. Four scenarios were provided to investigate the behavior of stabilization techniques explained in Table 4. In addition, Figure 6 demonstrates some samples of the camera motion paths for the four scenarios in Experiment C.  
\begin{table}
\begin{tabular}{l l} \hline \hline Camera & FLIR GF320 operating in the normal mode \\ \hline Distance & The distance varies between 4.6–15.6 m \\ \hline Gas & Methane \\ \hline Location & Methane Emissions Technology Evaluation Center (METEC) at Colorado State University \\ \hline Date & July 2017 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Details of the Experiment B.  
Figure 4: Sample photos of the GasVid dataset.  
\begin{table}
\begin{tabular}{l l l} \hline \hline  & **Session 1** & **Session 2** \\ \hline Acquisition Setup & DJI Mavic 2 Pro & Handheld camera, simulated camera movement \\ \hline Camera & Drone’s camera & FLIR GF309 cooled camera \\ \hline Location & TORGANTS, Quebec, Canada \\ \hline Date & November 2020 \\ \hline Sections & 6 & 9 \\ \hline Total Duration & 9 min & 17 min \\ \hline \hline \end{tabular}
\end{table}
Table 3: The details of Experiment C: the experiment includes two sessions recorded using a drone and a handheld thermal camera.  
\begin{table}
\begin{tabular}{l l l l l} \hline \hline  & **Datatype** & **Motion *** & **Sections** & **Description** \\ \hline Scenario 1 & Visible & Normal & 4 sections & Drones hovering during data collection. \\ \hline Scenario 2 & Thermal & Normal & 6 sections & Handheld camera simulating hovering motion with limited motions. \\ \hline Scenario 3 & Visible & Medium & 3 sections & Constant shaking motions and moving objects in the scene. \\ \hline Scenario 4 & Visible & Medium & 2 sections & Constant shaking motions. \\ \hline \hline \end{tabular}
\end{table}
Table 4: Details of scenarios in the Experiment C. * the motions are set to normal and medium. The medium motions are constantly shaking to investigate the resistance of stabilization methods.  
Figure 5: Sample photos of the drone-based experiment. The (**top left**) photo is a thermal image of the gas emission, the (**top right**) photo is a visible image collected by drone; the (**bottom left**) is a photo of the drone during the experiment and the (**bottom right**) is another photo sample of collected imagery data by drone.  
Figure 6: The sample of camera motion paths for the four scenarios in Experiment C.