## 3 Results
### Architecture of the EPM Control Unit  
To facilitate the functional connections of the direct-current motor that drives the EPM with the microcontroller contained in the development board, an L298N module with a double \"H\" bridge was utilized. As illustrated in Figure 6, the module integrates an L298 circuit and a 78M05 voltage regulator to 5 V.  
A selection of technical features of interest for the driver controlling the DC motor is detailed in Table 2.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Technical Specifications** \\ \hline Torque & Max. 5 kg\(\cdot\)cm \\ \hline Commutation & Brush \\ \hline Diameter & 25 mm \\ \hline Shaft length & 8 mm \\ \hline Weight & 100 g \\ \hline Supply voltage & 12 V DC \\ \hline RPM & 15 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Selection of key technical parameters of the CHR-GM25-370-12 V DC motor [24; 34].  
Figure 6: Schematic diagram of the L298N module with a double H bridge [35].  
To manage the control of the EPM, an ATmega328P microcontroller was utilized and integrated into the Arduino Nano development board, a cost-effective platform yet sufficiently performant to manage the control of the prosthetic module. The technical specifications pertinent to this board are enumerated in Table 3.  
These electrical components were integrated into the prototype of the control unit (CU) of the EPM (see Figure 7). The prototype has the capacity to establish a connection with a PC interface via a USB connection. The following presentation will outline the primary electronic components of the system: the development board, which integrates the microcontroller; the motor driver, which is responsible for controlling the EPM; and the LED feedback module, which is used for visual feedback during operation.  
Communication with the EPM is facilitated by a dedicated connection, ensuring synchronization and precise control of the prosthetic module. The device's power supply is derived from a 12 V source, which is connected through a stabilized power circuit. The configuration of this circuit was meticulously designed to satisfy the energy requirements of the system, thereby facilitating uninterrupted operational continuity. The on/off power control is facilitated by a dedicated switch.  
\begin{table}
\begin{tabular}{c c} \hline
**Parameters** & **Technical Specifications** \\ \hline Power supply & 5–35 V \\ \hline Peak current & 2 Amp \\ \hline Operating current range & 0–36 mA \\ \hline Control signal input voltage range & Low: \(-\)0.3 V \(\leq\) Vin \(\leq\) 1.5 V \\  & High: 2.3 V \(\leq\) Vin \(\leq\) Vss \\ \hline aMaximum power consumption & 20 W \\ \hline Input Voltage & 3.2 V–40 V DC \\ \hline Driver & L298N Dual H Bridge DC Motor Driver \\ \hline \end{tabular}
\end{table}
Table 2: Main technical characteristics of the L298N motor driver [35; 36].  
\begin{table}
\begin{tabular}{c c} \hline
**Parameters** & **Technical Specifications** \\ \hline Microcontroller & ATmega328P \\ \hline Input voltage & 7–12 V \\ \hline Operating voltage & 5 V \\ \hline Weight & 7 g \\ \hline Digital I/O Pins & 22 (6 of which are PWM) \\ \hline Analog IN Pins & 8 \\ \hline Power consumption & 19 mA \\ \hline Flash memory & 32 KB (ATmega328P) \\ \hline SRAM & 2 KB \\ \hline EEPROM & 1 KB \\ \hline Clock speed & 16 MHz \\ \hline \end{tabular}
\end{table}
Table 3: Technical parameters of the development board used [37].