Introducing Shaped Random and Burst Random Output Excitation in MIMO FRF Modal Analysis

Modal testing and analysis are important processes that improve the design of a product. Therefore, it is crucial to ensure testing is carried out with optimal settings. The Shaped Random and Burst Shaped Random output excitation introduced by Crystal Instruments provides unique advantages such as a better estimation of the quality factor, damping and FRF amplitude. This indicates that the obtained modal parameters are more accurate. A modal test is carried out to examine the data to see the improvement in the results with these newly introduced techniques when compared to the conventional shaker excitation signals. The green curve shows the FRF obtained using the Shaped Random excitation and the blue curve shows the FRF obtained using the white noise excitation. As illustrated, the advantages of shaped peaks using the newly introduced approach leads to more accurate estimations of the quality factor, damping and FRF amplitude as discussed in the forthcoming sections.

New Ultra-compact Spider-20H, Spider-20HE, & Spider-20i with 256 kHz Sampling Rate

Featuring the highest sampling rate provided in the industry at 256 kHz. Handheld battery powered system with wired & wireless network options and 20V input range. Sync between multiple devices. Choose the convenient portable model or industrial model for permanent mounting.

The Spider-20H, Spider-20HE, and Spider-20i received a hardware upgrade to support an impressive 256 kHz samping rate on all 4 input channels. It is the highest sampling rate offered in the market of compact analyzers. The high sampling rate is especially beneficial for measuring high orders and transient capture in blast tests, pyroshock events, drop shock tests, crash tests, etc.

In addition to the high samping rate, the input range is expanded to 20V to capture larger signals.

Spiders with 256 kHz Sampling Rate

Crystal Instruments EDM 9.0 release introduces new additions to the Spider product line featuring support for sampling rates up to 256 kHz.

The new Spider-80Hi and Spider-80Ci are scalable versions of the Spider system featuring the impressive new 256 kHz sampling rate. Recording can also be performed at sampling rates up to 256 kHz for all input channels, up to 512 channels per Spider system.

The compact, ultra-portable four channel version of the Spider has also been developed to support a 256 kHz sampling rate. Currently, three variations of the compact Spiders supporting the 256 kHz sampling rate are available: Spider-20H, Spider-20HE, Spider-20i.

EDM 9.0 Release

Crystal Instruments is pleased to announce our EDM 9.0 release, the most powerful and feature rich version of EDM software.

EDM 9.0 release supports the newly introduced hardware units (Spider-80Hi, Spider-80Ci, Spider-20i, Spider-20H, Spider-20HE) that support data acquisition and recording for up to 256 kHz.

In addition, the proprietary Multi-Resolution technology has been extended to benefit frequently used Vibration Control tests for Single-axis and MIMO tests. Several feature enhancements and bug fixes resulted in this more intuitive and user-friendly version.

NewsSandeep Mallela - Director of EngineeringJune 26, 2020Non-applications

Introducing Testing Plan in EDM Modal

With Modal Analysis software, all DOFs on the mesh of a structure under test needs be measured. The common practice is using the Input channel setting, with one incremental value to move on to the next batch of measurement points till all DOFs are measured.

Modal Testing & AnalysisJeff Zhao, Ph.D.June 25, 2020Structural Dynamics Testing

Modal Space - In Our Little World

Is there a difference between a roving hammer and roving accelerometer test? Well ... it depends. Let's explain what the differences could be.

NewsDr. Pete AvitabileJune 22, 2020

Modal Analysis of the Human Skull

Researchers at North Dakota State University have made great headway in understanding the behavior of the human skull under different strain rates. The study they carried out utilized a combination of computational and experimental modal analysis to compare the accuracy of different techniques used to model a human skull, and ultimately could increase the accuracy of dynamic simulations on the skull.

Comparison of Multi-Resolution Spectrum Technology and Regular FFT in Modal Analysis

Modal testing and analysis are crucial processes in the product development cycle. Sometimes the testing results are wrong by several magnitudes, especially in the low frequency bands where the frequency resolution is not sufficient. Crystal Instruments’ patented Multi-Resolution (MR) Spectrum technology helps overcome this issue with a unique solution.

Preview of Crystal Instruments 9.0 Release

Crystal Instruments is currently finalizing EDM 9.0, one of the most advanced versions EDM software.

With hardware introductions supporting an enormous 256 kHz sampling rate, the Spider hardware can now be deployed for a wide range of applications.

NewsSandeep MallelaMay 26, 2020Non-applications

Modal Space - In Our Own Little World

What are some of the major mistakes people make in modal tests so I don't make the same ones. Let's talk about some of them.

NewsDr. Pete AvitabileMay 5, 2020

Multi-Resolution Application in MIMO Sine Control

Multiple-Input Multiple-Output (MIMO) vibration testing has increased in popularity as a result of the development of multiple shaker table systems and the availability of MIMO vibration controllers. The readiness of standards such as Mil-STD 810G Method 527 and the IEST DTE 022 Working Group Recommendation have also contributed to the huge momentum MIMO testing has gained in the past decade.

MIMO Vibration TestingJeff Zhao, Ph.D.April 29, 2020Environmental Testing

Modal Analysis of Airplane Model Using EDM Modal

Analyzing the modal parameters of a structure is crucial in optimizing the mechanical properties of the test object. The natural frequencies, damping and mode shapes of the unit under test help in adjusting the design of the test structure which ultimately improves the structural behavior of the test unit.

Crystal Instruments April 2020 Webinar Series Summary

During the month of April, Crystal Instruments was proud to host two installments of our new webinar series. The first installment took place March 31st to April 2nd and focused on vibration basics, as well as vibration control testing for random vibration profiles. The second installment, which took place April 14th to April 16th, focused on modal analysis concepts and carrying out a modal test using Crystal Instruments Experimental Modal Analysis software.

NewsTrevor Ergas - Sales EngineerApril 24, 2020Non-applications

Strain Gage Connections

When designing and testing materials and products it is essential to understand its material properties and how it reacts to the forces and loads applied to it. The deformation a DUT experiences when a force is applied is called strain. Strain is the ratio of the change in length of a material to the original length. Strain can be positive (tensile) or negative (compressive).

Modal Space - In Our Own Little World

Is there any real advantage to MIMO testing?

Why not just use SISO and then move the shaker? Let's talk about the differences.

Multiple input multiple output (MIMO) testing has many advantages when compared to data collected from single input single output (SISO) testing. The energy from multiple shakers allows the structure to be more uniformly excited throughout the entire structure and thus allows for the development of better frequency response functions (FRF).

NewsDr. Pete AvitabileMarch 20, 2020