Session: 10-05-01: Applied Mechanics, Dynamic Systems, Experimental and Computational Methods, Modeling and Virtual Simulations of Dynamic Structures, Advanced Materials and Testing

Paper Number: 167474

Analysis of a Carbon Fiber Reinforced Aluminum Control Arm for a Baja SAE Suspension 

The Baja Society of Automotive Engineers (SAE) competition is an event where colleges across the world are tasked with designing an off-road vehicle that can traverse any obstacle the competition judges can design and fabricate. One of the primary rules of the competition is that all cars must be powered with a restricted 10hp engine that cannot be modified. For this reason, designing a lightweight vehicle is of significant focus to produce a faster, agile, and overall, more competitive car. More so, decreasing the weight of unsprung mass, or mass not supported by the coilovers, is of most concern because it has the greatest effect on the handling of the vehicle. One example of a part that has a significant effect on the unsprung mass of a vehicle is a control arm.  In a double wishbone or independent system, per corner of the vehicle, a control arm is one of the two A-shaped parts that controls the motion of the wheel during suspension movements. The control arm must be sufficiently stiff to ensure the motion of the wheel matches the intended design motion.  However, adding additional weight to achieve this stiffness will have a negative impact on vehicle perform.  Therefore, it is proposed an aluminum control arm that is reinforced with carbon fiber will achieve a control arm that is sufficiently stiff while decreasing the weight of the control arm in comparison to a standard control arm manufactured using steel tubing. The objective of this paper is to present a design of a carbon fiber-reinforced aluminum control arm that has equivalent performance to steel tube control arm but reduces the weight. Coupled with the presentation of the design, a computational analysis to ensure satisfactory bending and torsional stiffness will be presented.  To ensure the analysis is sufficient, equivalent computational modeling of a test specimen will be presented and compared to experimental testing. In this paper, performance is defined by the bending and torsional stiffness of the control arm. Following the design, a stress and deformation analysis of a carbon fiber-reinforced aluminum control arm is presented along with analysis of a baseline steel tube control arm. Subsequently, the manufacturing of a test specimen is covered along with the presentation and discussion of results from experimental testing of the test specimen. The computational and experimental bending and torsional stiffness of both designs are compared. Lastly, concluding remarks and future work on how a more refined design can be achieved are presented.

Presenting Author: Craig Altmann Virginia Military Institute

Presenting Author Biography: Craig Altmann is an Assistant Professor in the Mechanical Engineering department at the Virginia Military Institute where he teaches courses in the following areas: Dynamics, Dynamics of Machinery, Machine Design, FEA, and Automotive Engineering. He also serves as the Baja SAE advisor. Prior to VMI, Craig received his PhD from Virginia Tech for his research in identification of damaging road events and vehicle durability research. Craig’s current research interests are: Dynamics modeling and simulations, durability and fatigue modeling, composite material manufacturing and material testing, high fidelity measurement of off-road surfaces, and use of virtual reality to improve spatial visualization.

Authors:

Craig Altmann Virginia Military Institute
Diego Markie Virginia Military Institute