Steering Rod Fatigue Test Bench Cam Loading Analysis

Steering rods are subject to variety kinds of loads which will eventually cause failure. Automobile manufacturers and engineers are seeking ways to test the fatigue life of the steering rods. Steering rods under periodic loads over millions of cycles will get fatigued. We here provide a fatigue test bench for steering rods which applies periodic loads to the rod with a cam loading system. Cycloid motion is chosen for the cam follower to achieve the smooth and stable kinematic performance in middle and high speed operation. The accuracy of the follower response is analyzed using dimensionless dynamic equation and the application of Matlab is introduced to solve elastodynamic equation and analyze the prime/residual vibration curve of the follower. The cam loading system is built in dynamic analysis software Adams to simulate its virtual operation performance. By calculating the velocity multiplied by acceleration of the follower over the operation period, the extent to which the inertia load from the follower affects the torque on the cam shaft will be obtained with the help of Adams/postprocessor. The force loads acting on the cam shaft can also be acquired using simulation tools. By virtual prototyping the cam loading system’s performance can be foreseen before a real prototype is built. Introducing cam loading method into fatigue test is an innovative application. © 2012 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved