Architected gripper fingers: design, additive manufacturing, and experimental characterization

Abstract

Soft robotic manipulators provide an approach to manipulate delicate and fragile objects. Their performance depends mostly on its material flexibility and finger design. This study explores architected gripper fingers designs featuring sinusoidal structures manufactured via fused filament fabrication using thermoplastic polyurethane. The deformation behavior was experimentally characterized through image analysis of geometry conformity to assess adaptability and load-deformation test using a stepper motor and analog dynamometer. Performance was analyzed implementing robotic manipulation trials using an Xarm. The results showed that distance between curved ribs demonstrated higher flexibility, with greater deformations per load step. Withing the designs, models with increased number of waves achieved better adaptability, while those with ribs spacing variations exhibited higher stiffness. Robotic manipulation experiments confirmed that architected fingers improved grasping performance and reduced damage when handling delicate objects. This study provides a foundation for developing robotic applications, demonstrating that the proposed configurations are capable of safe manipulation. The combination of design parameters and additive manufacturing techniques enables the creation of customized and functional fingers that can adapt to various delicate objects.