Some Considerations in the Test Bogey Development for Automotive Components

Test bogeys are valuable tools in providing guidance in design iterations as well as serving as gatekeepers in laboratory endurance tests for product certification. In addition, test bogeys have been used to screen manufacturing process-induced performance variations. Typically, the endurance test specification consists of descriptions of parts to be included in a test setup, the minimum number of test samples of the target component, the load, and the number of cycles, block cycle repeats, or test time to exceed without failure. To define these test bogeys, however, is a special challenge for heavy and medium duty vehicle applications. Oftentimes, neither a representative field duty nor a well-developed proving ground test cycle is available. Furthermore, there are numerous vehicle configurations and broad variations of application. A test bogey that is adequate for one case might not be suitable for a seemingly similar case. Ideally, what we need is a flexible and reliable methodology for test bogey development that can be used routinely and cost effectively. One method suggested by this paper is to conduct the integrated simulation and modeling in which vehicle dynamics simulation, component FEA (Finite Element Analysis), and fatigue life calculation are conducted along with test measurements. For illustration, scenario studies of a test bogey development exercise for a heavy vehicle integrated axle/suspension system is provided.