Machine condition based monitoring plays an important role in securing the stealth of the submarine, as any vibration related tone passed through the hull to the outside world could betray the vessel. All onboard equipment must be meticulously monitored and maintained.
Read MoreAnyone who has lived or worked at or near a construction site is familiar with the sound of pile driving, or the mechanical driving of specialized poles into the earth to provide foundational support for buildings. The noise and vibrations of the work may continue at high decibels over a prolonged period of time.
Read MoreIn the new flick The Martian, vibration testing becomes a matter of life and death, survival or starvation, when a supply probe bound for Mars and loaded with nourishment for our lonely red planet hero (Matt Damon) fails mid-launch.
Read MoreFatigue Damage Spectrum (FDS) allows users to compare the potential damage caused by different Random profiles, swept Sine profiles or a combination of both.
Read MoreIt is not easy for human eyes to see the modal shape at various frequencies. If we can freeze the motion at the desired frequency, we can capture the modal shape created. A stroboscope is a device which flashes light at a resonance frequency of an object to make the object appear stationary.
Read MoreThe new Engineering Data Management software release from Crystal Instruments, EDM 5.1, improves ease of use, performance, and scalability of the associated hardware. The updated software version, introduced approximately 7 months from the previous 5.0 release, features enhancements to the high channel count configuration, as well as Multi-Sine control, Multi-exciter single-control for Sine, Fatigue Damage Spectrum (FDS) in Random, and Transient Random control. The release also supports the brand-new handheld dynamic signal analyzer, Spider-20.
Read MoreThe Spider series of dynamic signal analyzers by Crystal Instruments welcomes its newest product, the Spider-20, which at 5 x 4 inches and 18 ounces is the most compact instrument in the product line.
Read MoreCrystal Instruments continued to achieve relevance in wider global markets when the Spider-80X dynamic measurement system received certification from the Russian State Register of Measuring Instruments. The certification was obtained in partnership with Dipaul, Crystal Instruments' Spider-80X Russian distributor, and allows the highly scalable vibration controller and dynamic signal analyzer to be sold in Russia.
Read MoreCrystal Instruments shipped over fifty CoCo-80 handheld vibration monitoring devices in the month of June 2015. Used for preventative maintenance, vibration testing, and machine monitoring, the flexible software of the CoCo-80 allows technicians to easily take data through customized applications.
Read MoreModal testing is a common method to determine the characteristics of an object through exciting the structure to a certain vibration level and obtaining its resonance frequencies. It is important for a brake system to keep vibration under control during operation because excessive vibration while braking could cause driver discomfort, premature and irregular tire wear, and stress on steering and suspension components.
Read MoreNano-satellite developer Aquila Space has formed a strategic partnership with Crystal Instruments and Sentek Dynamics to test a prototype of its three-spectral-band imager, the primary payload of a 6U CubeSat scheduled to launch at the end of 2015.
The imager, comprised of three cameras which capture pictures of the earth from space, was subjected to vibration tests including a Resonance Survey, Sine Sweep, and Random Vibration affixed to Sentek Dynamics' 50 kN shaker controlled by Crystal Instruments’ Spider-80X Vibration Test Controller.
Read MoreThe Shaped Random function, which is capable of producing a carefully tailored random spectrum, is available in all of Crystal Instrument’s dynamic signal analyzers. The various constructions of the profiles can produce types of noise such as white noise, pink noise, and more. The Shaped Random function allows a tailored signal generation.
Read MoreIf an experimental measurement matches the Gaussian PDF model, the Gaussian model can then be used to draw many important inferences about the measurement. Many statistical curve-matching tests are available to establish if a measurement is Gaussian. These include the Kolmogorov-Smirnov (KS), Shapiro-Wilk and Anderson-Darling tests. For practical purposes, most well-fixtured and well-conducted random shake tests will produce data that pass any of these model-matching statistical tests for Gaussian behavior.
Read MoreThe mean and variance dominate statistical measurements in both the time and frequency domains. They are also reflected by so-called amplitude domain measurements. The most basic of these is called a histogram. To measure a histogram, break a signal’s potential amplitude range into a contiguous series of N amplitude categories (i.e. x is between a and b) and associate a counter with each category.
Read MoreOne statistical description measured during a random shake test is the Control Spectrum. Specifically, this variable is often the output of an accelerometer mounted to the shaker table. The sensor’s voltage output is scaled to engineering units of acceleration, typically gravitational units (g’s) sampled at a fixed interval, Δt. This time-sampled history is transformed to the frequency domain using the Fast Fourier Transform (FFT). In this process, a series of “snapshots” from the continuous time waveform are taken and dealt with sequentially.
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