Sistem Monitoring Dan Kontrol Terdistribusi Berbasis Smart HMI Dan Mikrokontroler Bare-Metal Pada Purwarupa Simulator Iradiator Gamma Tipe 4

Distributed Monitoring and Control System Based on Smart HMI and Bare-Metal Microcontroller in Type 4 Gamma Irradiator Simulator Prototype

Abstract

The development of automation technology in Type 4 gamma irradiator facilities requires reliable monitoring and control systems to ensure operational efficiency and safety from potential radiation exposure hazards. This study aims to design and implement an automated monitoring and control system on an irradiator simulator prototype based on a distributed Human-Machine Interface (HMI). The system adopts a bare-metal control architecture using the Arduino Mega 2560 microcontroller as the deterministic logic processing center, integrated with a 10.1-inch Nextion Intelligent Smart Display as an independent visual interface unit. This workload isolation is designed to relieve the microcontroller from graphical rendering tasks and logarithmic decay floating-point computations by implementing a static dose rate approach (5.203 Gy/sec), thereby allowing processor capacity to focus entirely on mechanical actuator synchronization and emergency response (safety interlock). Data communication between devices is executed using a hexadecimal instruction protocol via UART serial communication. Test results indicate that the HMI interface can present mechanical status updates, accumulated dose calculations, and operational percentages in real-time without latency or packet loss at 9600 bps. The irradiation time distribution algorithm proved precise in executing conveyor and source rack stepper motor actuators with a duration deviation of less than 2%, supported by a passive rotary table mechanism with an 8.8-second 360° rotation period that guarantees dose uniformity (DUR close to 1). In emergency testing scenarios, the safety interlock mechanism responded deterministically by cutting off current to the solenoid (fail-safe) and activating an automatic safeguarding routine (emergency overdrive) in less than 7 seconds to return the simulator to a safe position. Overall, the developed system proved stable, responsive, and highly feasible as an educational automation demonstration tool for nuclear facilities based on safety culture.