Investigation of Composite Stepped Splined Shaft for a Terrain Vehicle Application

Abstract

Producing a light structure with relatively affordable cost without sacrificing strength and torsion effect has always been a challenging task for designers. Using a composite material approach provides an expanded methodology to combine materials having different costs and properties. Hence, a comparative approach is useful for the evaluation of design solutions in terms of weight and thickness of a ply. Substituting composite structure for a conventional metallic structure has many advantages because of a higher specific stiffness and strength of composite material. In this study a methodology of combining analytical design and numerical validation of composite stepped splined shaft for the replacement of conventional shaft with Eglass/Epoxy shaft, High strength-carbon/Epoxy shaft and High modulus-Carbon/Epoxy shaft for a terrain vehicle application is presented. The criteria’s in which the design and modeling of both conventional steel shaft and composite shaft are Torsional transmission capability, Torsional Strength, buckling torque capability and bending natural frequency. The composite laminate face sheets considered consisted of thin composite face sheets, symmetric with respect to the mid-plane of the composite plates. The face sheets considered consisted of E-Glass/Epoxy, High strength-Carbon/Epoxy, and High modulus-Carbon/Epoxy fiber-reinforced polymer. The layup of the fibers of the face sheets was restricted to some discrete sets of plies layup having orientation angles of 0, ±45 and 90. Autodesk Inventor Professional 2018 is used to model stepped splined shaft with specific dimensions and Ansys Composite Prepost(ACP) student version is used to analyze a composite uniform equivalent shaft with specific thickness and number of plies according to the optimization result taken from the MATLAB code and Interior point algorithm used to perform single objective optimization subjected to required equality constraint and inequality constraints based on the thickness and number of plies. The design optimization and optimum design of the composite shaft for the criteria mentioned above showed significant potential improvement in the performance of stepped splined shafts.