Abstract

The global trend of replacing plastic straws with environmentally friendly alternatives has significantly increased the demand for biodegradable straws such as those made from Lepironia grass. However, the current production process still heavily relies on manual labor, particularly in the stage of cleaning the inner velvet layer of the grass stem—an essential step for ensuring product quality. This study focuses on the mechanical design and development of a core removal and inner-cleaning system capable of processing 100 straws per minute. The proposed system consists of three main units: the cleaning unit, positioning unit, and clamping unit, supported by auxiliary mechanisms including a feeding system and product discharge module. A spatial cam mechanism is employed to generate both translational and rotational motion for the cleaning probe, enabling efficient removal of the inner velvet layer while allowing flexible adaptation to different straw diameters. In addition, the system utilizes an elastic belt-based positioning mechanism and a synchronized rotary structure to ensure smooth operation, minimize error, and prevent straw breakage. This modular mechanical design not only enhances productivity and precision but also contributes significantly to the mechanization of the Lepironia straw production process. It promotes sustainable development by reducing labor dependency, improving product consistency, and supporting the local raw material industry. The study represents a crucial step toward automation and localization of straw production equipment, addressing the need for cost-effective and environmentally responsible manufacturing while leveraging the native Lepironia grass resource found abundantly in the Mekong Delta region of Vietnam.