# Infrared Thermographic Signal Analysis of Bioactive Edible Oils Using CNNs for Quality Assessment
## 3 Materials and Methods: Thermographic Signal Acquisition System  
A really important part of the study involves acquiring the information to be processed, which is specifically carried out by an electronic device used to acquire the thermographic signal and a processor that stores and sends the data to a cloud platform. The implementation of artificial intelligence techniques allows for the analysis and implementation of the acquired data. For the design and implementation of the system, tools for signal acquisition and processing are used. In particular, a thermographic sensor (MLX90640, 32 \(\times\) 24 resolution), an acquisition board based on an ATMEGA328P microcontroller with 10-bit ADC, a variable linear power supply (\(\pm\)12 V, 1 A max), and a Raspberry Pi acting as a digital converter and control processor. The study and processing of the signal occur thanks to the electronic measurement system, whose purpose is to record and process the measurements of the emitted signal. After the conversion from analogue to digital form, the signal is sent to an integrated circuit composed of a Raspberry processor, which is responsible for taking the information acquired from the circuit and sending it to a cloud platform [70]. The acquired images undergo feature extraction and subsequent implementation with AI techniques. The hardware design of a thermographic signal acquisition system requires the careful evaluation of various components and functionalities to ensure the device's effectiveness, safety, and reliability. For this reason, targeted, constant, and intensive monitoring of thermal parameters was carried out. Monitoring was performed by a central unit composed of an acquisition board and a processor, responsible for storing and processing signals from the thermographic sensor connected to the acquisition circuit. The acquired signals are managed by an intelligent system, On Module (SOM), which is an independent electronic device capable of managing a Linux operating system and performing complex numerical calculations [71; 72]. The acquired signals are then saved in a database, which stores them and makes them available for management and processing (Figure 1). Specific details may vary depending on the intended use and the technology used. The acquisition circuit proposed in this study was designed according to the diagram shown in Figure 2. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Component** & **Per 100 g** & **\% RDA/AI** \\ \hline Energy & 814 kcal & 40.7\% \\ Total Fat & 90 g & 138.5\% \\ Saturated Fat & 18 g & 90\% \\ Monounsaturated Fats & 30 g & - \\ Polyunsaturated Fats & 42 g & - \\ Phytosterols & 230 mg & - \\ Vitamin E & 10 mg & 66.7\% \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Nutritional composition of pumpkin seed oil. Figure 1 shows the thermographic monitoring system where oil samples are enclosed within a thermally insulated polystyrene container subjected to controlled heating and cooling cycles. Figure 2: Schematic of the electronic system for real-time thermographic monitoring of oil samples, featuring a Raspberry Pi, ATMEGA328P, wireless module, and thermal camera interface. Figure 1: Schematic representation of the thermographic monitoring setup for oil samples. The system (Figure 1) shows the thermographic monitoring of oil samples contained within a thermally insulated polystyrene box, subjected to controlled heating and cooling cycles using a Peltier element. The system has a Raspberry Pi as the main control and data acquisition unit connected to an acquisition board, which is responsible for interfacing the thermal imaging components and managing the heating and cooling process with the Peltier cell. The Raspberry Pi provides both 5 V and 3.3 V power lines through its GPIO header, which are used to power the microcontroller unit and peripheral protection circuits. The system detail, represented in Figure 2, highlights the presence of a resettable fuse rated at 500 mA, capable of ensuring stable and safe operation.