A 6-DOF 3-D-Printed Intelligent Robotic Manipulator for Automated Material Sorting

This study presents the development of an advanced six-degrees-of-freedom (6-DOF) robotic manipulator tailored for automated material sorting applications. The system builds upon a previously published five-degrees-of-freedom (5-DOF) three-dimensionally (3D) printed robotic arm, originally designed for simple sample-transfer tasks. In this study, the manipulator was significantly enhanced to operate as a fully automated and intelligent sorting platform that emulates industrial-grade environments. The improved system incorporates a conveyor belt for automated sample feeding, ultrasonic sensor for object detection, and infrared (IR) sensor for material classification based on pre-calibrated reflection thresholds. An additional degree of freedom (DOF) was introduced to increase the arm’s vertical-axis flexibility, and a liquid crystal display (LCD) interface was added to deliver real-time operational feedback. Furthermore, a comprehensive control algorithm was developed to autonomously coordinate the sensing, classification, and sorting operations. The experimental results demonstrated a high accuracy in material recognition, stable and consistent motion performance, and efficient energy utilization. These outcomes establish the proposed manipulator as a promising prototype for smart manufacturing applications, as well as an effective platform for educational robotics.