Canta, Maria Jeriah V. <br/><br/>
Petr:   automated polyethylene terephthalate (pet) recycler pultrusion machine with a diameter consistency pid control system using computer vision/ 
Maria Jeriah V. Canta, Jessie F. Logrono, Lieneth A. Maylas, Cherie Ann C. Nelmida, and Vince Elrey O. Tolledo.-- 
 - Manila:	  Technological University of the Philippines,	  2025. 
 - xi, 168pages:  29cm. 
<br/><br/> Bachelor's thesis<br/> 
<br/><br/>College Of Engineering.--<br/> 
<br/><br/>Includes bibliographic references and index. 
<br/><br/> The rapid rise in plastic production poses a serious threat to aquatic ecosystems, with an<br/>estimated 13 to 19 million metric tons of plastic entering water bodies each year. Asia<br/>alone contributes approximately 82 million tons of plastic waste, making it the largest<br/>source of global plastic pollution. As the demand for sustainable materials in 3D printing<br/>continues to grow, there is an urgent need to develop methods for converting plastic<br/>waste into alternative filament sources. This study addresses that need by designing and<br/>building a 3D printer filament pultrusion machine that features automation and real-time<br/>monitoring. The system uses PID control through an Arduino Uno R4 microcontroller to<br/>regulate the stepper motor, heating nozzle, and spooling mechanism, which all work<br/>together to produce consistently wound PET filament. In addition, a computer vision<br/>system using machine learning was set up on a Raspberry Pi 5 to monitor filament<br/>diameter in real time. The goal was to maintain a consistent 1.75 mm diameter, with an<br/>acceptable 5% margin of error (1.66mm to 1.84mm). YOLOv8 was used instead of Mask<br/>R-CNN because it worked faster and more efficiently on the Raspberry Pi. To measure<br/>the filament, OpenCV was used, offering a more affordable method compared to laser<br/>systems. The tests used Nature Spring 1-liter PET bottles, cut into strips with widths<br/>between 9.0 mm to 9.6 mm and a thickness of 0.2 mm. It was found that the width and<br/>thickness of the strip had an effect on whether the filament could consistently reach the<br/>target diameter. Consequently, to check the quality of the filament, a pendulum impact<br/>test was done, along with test prints using a 3D printer. Measurements from the computer<br/>vision system were compared with results from a caliper, and had an accuracy of 98.73%.<br/>This project shows how waste PET bottles can be turned into usable 3D printing filament. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Plastic production<br/>Aquatic ecosystems<br/>Filament machine
<br/><br/><label>LC Class. No.: </label>BTH TK 870  / C38 2025