## 3 Materials and Methods
### Blackbox Devices' Concept and Development
The compact and modular design supports portable operation in clinical and home environments, facilitating edge-level signal processing and secure data transmission to cloud infrastructure. Figure 2: The final model of the EMG Blackbox. The final assembled prototype of the EMG Blackbox, showcasing its compact design for portable biomedical monitoring applications. The image highlights key components, including the embedded microcontroller board (Arduino Mega), Li-Po battery pack (7.4 V, 2500 mAh), wireless communication module (NodeMCU ESP8266), and integrated EMG signal acquisition sensors. Internal wiring and modular connectors are organized to support reliable signal acquisition and efficient power distribution. This configuration allows for real-time data processing and wireless transmission to edge computing nodes, ensuring robust operation in laboratory and home-care settings. * _Custom interface openings_: Strategically placed cutouts for sensors, power, and data ports, minimizing interference. * _Fastering and accessibility_: Predefined mounting holes and alignment guides facilitate secure assembly and maintenance. * _Manufacturing readiness_: Optimized for 3D printing, ensuring precision, repeatability, and material efficiency. Key design considerations
* _Dimensional accuracy_: Defined length/width parameters for precise fit and structural integrity. * _Feature placement_: Central cutout for connectors, sensors, or ventilation. * _Alignment and constraints_: Geometric symmetry ensures parametric adaptability. * _Manufacturing preparation_: Sketch optimized for extrusion, fileting, and fastening integration. Figure 4 presents the fully developed 3D model of the Medical Blackbox cover, designed for seamless integration with the enclosure. The model incorporates precisely positioned cutouts, fastening points, and structural reinforcements to enhance functionality and system performance. * _Component-specific cutouts_: Geometrically optimized openings for sensor exposure, display integration, and thermal dissipation. * _Precision fastening_: Predefined corner mounting holes ensure secure, vibration-resistant attachment while maintaining accessibility. * _Multi-plane design_: Slanted and recessed surfaces enhance ergonomics, esthetics, and mechanical robustness. * _Manufacturing and assembly readiness_: Optimized for additive/subtractive manufacturing, ensuring tight tolerance and reliable interlocking with system components. Data Transmission Framework  
Through the use of BLE and Wi-Fi protocols, which both enable Transport Layer Security (TLS) 1.2/1.3 and Secure Socket Layer (SSL) for encrypted communication, ensuring authentication and integrity, the Monit4 Healthy system enables secure information  
Figure 4: The finished model of the Medical Blackbox’s lid. The finalized model of the Medical Blackbox’s external casing, specifically its custom-designed lid. The enclosure was designed to ensure physical protection for internal electronic components, including the microcontroller, sensors, and communication modules, while maintaining accessibility for maintenance and upgrades. The lid incorporates ventilation slots for thermal management and designated ports for sensor connections, power input, and wireless communication interfaces, ensuring reliable and safe operation during portable health monitoring activities. exchange. TLS guarantees all external data transmissions to cloud services, whereas BLE is employed for local, short-range biomedical data communication. In particular, the system uploads data to the ICIPRO cloud infrastructure--which is designed for the secure processing and storage of sensitive data--using TLS-encrypted communication. The ICIPRO infrastructure provides certified secure settings for digital health solutions. As part of its compliance to national cybersecurity regulations, ICIPRO uses TLS protocols to establish server-side encryption and enforces data isolation, access control constraints, and encrypted backups.