Visualizing the Orbit Trace of a Three-axis Shaker

This section describes the orbit plot feature in the vibration visualization function. In-depth details about the workflow of the vibration visualization process will be discussed in the later portion of the article. The orbit plot is not only used to understand the magnitude of the vibration during a vibration test but also to observe the phase relationship between the different channels used to acquire the response of the unit under test. This is understood more clearly using a test case.

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Operational Modal Analysis of Scaled Building Structure using EDM Modal

Operational Modal Analysis (OMA) is commonly used to monitor and evaluate the health of building structures to investigate for any damage [1]. Studying the modal parameters of the structure can assist in observing changes in the dynamic properties which can further help in predicting error in certain elements which might need some repair or modification.

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Modal Shaker Testing Using Periodic Random Excitation

Two somewhat arbitrary types of excitation signals are Pseudo Random and Periodic Random. The characteristics of these two signal types will be discussed in detail here. The results of using these excitation types will be compared to the more popular Pure Random and Burst Random types. It will be shown that the cost of additional testing time is well worth the superior estimation of MIMO FRF signals.

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Four Popular EV Battery Vibration Testing Profiles

Lithium-ion batteries are gaining popularity as the most common battery type used for electric vehicles. During their lifespan, these batteries undergo a variety of vibrations and temperature changes. Several common test standards have developed to simulate the long-term environmental effects on these batteries across different size levels (e.g. cell, module, pack).

Of the many test standards for EV batteries, this post will specifically focus on the vibration and temperature aspects of four well-known standards: SAE J2380, SAE J2464, IEC 62660-2, and UN 38.3.

Crystal Instruments Spider systems can provide solutions for random, sine, and shock vibration test, as well as temperature control.

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Modal Analysis of Airplane Model Using EDM Modal

In this case, the modal characteristics of an airplane model is acquired by performing experimental modal analysis. A SIMO FRF test is carried out using a single modal shaker and multiple sensors to obtain the vibration characteristics. Shaker excitation provides better consistency and repeatability than a modal hammer. It also produces a cleaner data set because of a greater average. The higher quality measurements lead to a better estimation of the modal parameters.

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