Three-Dimensional Sewing Using Conical Rollers with Biaxial Anisotropic Friction

In this paper, we propose a novel, fixture-free, three-dimensional (3D) sewing system. In 3D sewing, the fabric parts are sewn together along seams that are defined separately for the upper and lower fabrics. To sew the fabrics along their respective seams, the upper and lower fabrics must be manipulated independently. Our proposed mechanism uses a conical roller with "conchospiral" ridges to manipulate each fabric around the sewing needle, generating biaxial anisotropic friction between the roller and the fabric. First, we discuss the design of the conical roller with the conchospiral ridges. Then, we evaluate the biaxial anisotropic friction characteristics of the proposed rollers with different design parameters. The experimental results demonstrate how the traction of the roller with different fabrics is affected by the offset angle of the roller. Finally, we conduct sewing experiments using an automated 3D sewing system with the proposed mechanism. These experiments demonstrate the effectiveness of using the conical roller with conchospiral ridges for 3D sewing, achieving a level of sewing accuracy that is sufficiently high compared to that observed in real car seats.