Reference Materials

(Materials provided courtesy of Crystal Instruments)

Vibration Control

What's Required to Bring Vibration Testing In House? (5 MB) Cover Story for March 2016 Sound and Vibration Magazine

History of Vibration Control Systems (Product Note #004, published in Sound & Vibration Magazine, 0.4MB) This article discusses the four generations of digital vibration control systems developed by US companies in the past 4 decades.

Understanding Random Vibration Testing Signals (Product Note #027, 6 pages, 2.43 MB)
Random vibration testing signals are explained and discussed for the testing professional.

Using Fatigue Damage Spectrum with Vibration Control (Product Note #028, 3 pages, 2.10 MB)
Fatigue Damage Spectrum (FDS) allows users to compare the potential damage caused by different Random profiles, swept Sine profiles or a combination of both.

Visualizing Mode Shapes with a Stroboscope and Cola Output (Product Note #029, 3 pages, 1.44 MB) Product application note discussing the use of a stroboscope to visualize mode shapes with Crystal Instruments' Spider systems.

Random Control Feature: Non-linear Control (Product Note #030, 3 pages, 756 KB) Crystal Instruments’ Random Control implements an advanced algorithm which compensates for the effect of non-linearity in the control loop, regardless of whether it is caused by the type of shaker system or the resonance of the device under test.

Sine - Resonance Search Track & Dwell Tracking (RSTD) (Product Note #31, 5 pages, 878 KB) This product note demonstrates the use of Crystal Instruments’ Spider 80X along with EDM (Engineering Data Management) software to determine the resonant frequency of a test object with a very high Q and dwell on the resonant frequency along with tracking the changes in the resonant frequency using the phase value.

Random Control Feature: Multi-Resolution Control (Product Note #32, 6 pages, 945 KB) The Multi-Resolution function perfectly fulfills the requirements of many Random profiles having details in the low frequency range and up to 2kHz. Adequate loop time, spectrum refresh rate, and storage are maintained without using high resolution (large block size) that is not needed in the high frequency.

Multiple Shaker Control in EDM Software (Product Note #34, 7 pages, 1043 KB) Multi-shaker control (MSC) is a unique feature offered by Crystal Instruments EDM Software versions 7.0 and above. The EDM MSC function enables users to view and monitor multiple shaker tests from one PC station. Users can observe testing status, view individual signals from different shaker systems, and send commands to each controller from one centralized application.

High Resolution Random Control at Low Frequencies (Multi-resolution) (Product Note #041, 3 pages, 588 KB) The trade-off between control performance at low frequencies and the whole system response is always difficult, but Crystal Instruments has the solution: Multi-Resolution Random Control.

MIMO Vibration Control vs. Single Shaker Vibration Control (Product Note #046, 3 pages, 561 KB) With the development of multiple shaker table systems, the availability of Multiple Input Multiple Output (MIMO) controllers and Multiple Input Multiple Output (MIMO) vibration control started emerging a couple of decades ago.

Multi Shaker Table Systems (Product Note #047, 3 pages, 461 KB) The Multiple Shaker Table System ranges from Multiple Exciter Single Axis (MESA) to Multiple Exciter Multiple Axis (MEMA) with 2 to 6 shakers involved (e.g., three axis translational shaker table, four-poster, 6 DOF Multi Axis Shaker Table (MAST), etc.)

Modal Testing and Analysis

Basics of Structural Vibration Testing and Analysis (Product Note #006, 14 pages, 2.69 MB) 
This application note provides an introduction to the basic concepts of structural vibration. It presents the fundamentals and definitions in terms of the basic concepts. It also discusses practical applications and provides real world examples.

Basics of Modal Testing and Analysis (Product Note #007, 12 pages, 4.15 MB) 
This paper discusses the concept of modal analysis, its applications where modal analysis is useful, data acquisition and visualization techniques.

Modal Data Acquisition Using the CoCo-80X/90 (Product Note #015, 8 pages, 953.85 KB)
Explains how the CoCo-80X interfaces to the modal analysis software in EDM Modal (Engineering Data Management software) and how the modal data is captured.

Modal Testing Preparation Considerations (Product Note #033, 3 pages, 881 KB)
In this technical note, the emphasis is to discuss the necessary technical details regarding the preparation of a successful modal test to acquire a set of FRF signals.

Experimental Modal Analysis Overview (Product Note #043, 4 pages, 470 KB)
Experimental Modal Analysis (EMA) has developed into a major technology for the study of structural dynamics in the past several decades.

Modal Shaker Testing Using Periodic Random Excitation (Product Note #040, 4 pages, 744 KB)
Modal shaker testing is widely used for experimental modal analysis and to acquire frequency response functions. Either single or multiple modal shakers can be used. The type of excitation used may influence the quality of the testing result and frequency response functions.