Design, Fabrication, and Testing of a CFRP Drive Shaft With Centering Structure

ABSTRACT

Transmission shafts in engineering systems are prone to misalignment, leading to vibration, noise, and reduced service life. Conventional diaphragm couplings can compensate for misalignment but increase structural complexity and system mass. To address this limitation, an integrated carbon fiber reinforced polymer (CFRP) transmission shaft with a centering compensation structure is proposed in this study. The effects of key geometric parameters, including the angle θ , axial length ( L ₂ ), and outer diameter ( d ₄ ), on torsional and bending stiffness are investigated using finite element analysis. A fabrication process based on autoclave molding is developed, and prototype specimens are manufactured for experimental validation. Results show that the angle has little influence on torsional stiffness but significantly affects bending stiffness and centering performance. Increasing axial length or reducing outer diameter decreases overall stiffness, thereby improving misalignment accommodation. Experimental results demonstrate that the proposed shaft maintains stable torque transmission under a 0.5° misalignment while sustaining a torque of 7500 N m. The proposed design provides an integrated lightweight solution for simultaneous torque transmission and misalignment compensation without additional coupling components.