Desenvolvimento de um dispositivo de secagem e monitoramento do filamento PLA utilizado para impressões 3D

Abstract

This work aimed to develop a microcontroller-based system for the drying and weighing of 3D printing filaments, seeking to mitigate material degradation caused by moisture, which compromises the mechanical strength and structural integrity of printed parts. The proposed system was implemented with the STM32F103C8T6 microcontroller and utilizes the DHT22 sensor to monitor temperature and humidity, and the HX711 module with a load cell for filament weight measurement, allowing for the tracking of remaining material. The human-machine interface (HMI) was developed with a ST7735 TFT display and a rotary encoder (KY-040) for navigation and adjustment of drying parameters, namely temperature and time. Thermal control is based on the On-Off method with hysteresis to optimize stability. Experimental validation, focused on PLA filament, included mechanical tensile and flexural tests. The results demonstrated that the humidified filament suffered a significant reduction in stiffness and mechanical strength. Following the drying process in the prototype, the mechanical properties were significantly restored, proving the device's effectiveness in partially reversing moisture-induced damage and recovering the material's quality for additive manufacturing.