Increasing Multi-Axis Testing Confidence Through Finite Element and Input Control Modeling

Testing devices multi-axially can be a better approximation of a device’s operational conditions compared to single-axis testing. However, multi-axis environmental tests involve a more complicated test setup that is often determined by a test engineer’s judgment. Some of the complexities the engineer must determine include where to locate shakers on intricate geometries, how much input is required to excite the structure, how many control channels are necessary, and how well the environmental test boundary conditions replicate the operational environment. Any one of these things can lead to the device under test’s (DUT) response differing greatly from the desired response. Often there is no indication of whether the environmental test setup appropriately replicates field conditions prior to the start of the test. The ability to simulate a test on a finite element model (FEM) would allow the engineer to have insight into the predicted response of the DUT prior to performing an environmental test. This study uses Sandia National Laboratories Rattlesnake control software to conduct virtual tests on an FEM of the base section from a Box Assembly with Removable Component (BARC) and aims to determine if virtual testing can be used to predict optimal environmental test setup accurately and achieve the desired response from the DUT. Including a virtual test as a step in the procedure for multi-axis vibration testing could provide test engineers with the necessary information for a reliable test such as input controls and locations, equipment requirements, and sensor placement prior to performing a test, reducing the time required in the lab, and improving test results.