Small satellites, more commonly known as CubeSats, have gained popularity because of their miniature size and their data acquisition techniques. These satellites are being launched at a record pace and have roped big players into this aerospace segment. Astro Digital is a company that risen to the challenge of land mapping and hazard detection using CubeSats.
Astro Digital has been creating APIs and CubeSats for geological mapping, natural disaster management, forest management, water cover sensing, etc. Sentek Dynamics is proud to have a hand in their projects.
Read moreDespite the storm-torn state of host town Jacksonville, Florida undergoing restorations, the 88th Shock and Vibration Exchange carried on with its usual vivacious atmosphere. Folks flew in from all around the world to share their groundbreaking ideas on shock and vibration measurement. HI-TEST Labs did the exemplary job of planning the entire event.
Read moreExperimental Modal Analysis (EMA) is an important tool that is applicable for many structural vibration analysis situations. Fundamental aspects of performing a successful modal analysis include preparation, FRF data acquisition, modal parameter identification, and modal model verification.
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.
Read moreCrystal Instruments (CI) is pleased to announce the opening (effective July 2017) of its first Russian office. Located in the city of St. Petersburg, Russia, Crystal Instruments chose this site due to its unique combination of both culture heritage and industrialized technology subdivisions.
Read moreCrystal Instruments was pleased to exhibit a the annual Automotive Testing Expo China in Shanghai, China from September 19 - 21, 2017. The international Automotive Testing Expos are ideal for previewing the latest developments in testing technologies used in the automotive production process.
Read moreCrystal Instruments and Sentek Dynamics partnered together in Tokyo, Japan at the Test 2017 show on September 13 - 15, 2017.
Crystal Instruments featured innovative new testing solutions:
- EDM Modal - Complete Modal Testing & Analysis Software Suite
- CoCo-80X - Handheld Touchscreen Dynamic Signal Analyzer
- Spider-80Xi - Compact & Modular Dynamic Measurement System (scales up to 512 channels)
Sentek Dynamics offered turn-key solutions and environmental testing systems:
- Electrodynamic Shakers - Low, medium, high, and extra high force shakers available. Three axis, permanent magnet, long stroke, and high performance shakers also available.
- THV Environmental Test Systems - combines three testing environments (temperature, humidity and vibration) in one chamber.
Read moreEngineering Data Management (EDM) is the software platform supporting all Crystal Instruments products. It is the center of testing and data management for carrying out daily operations. Crystal Instruments is expending relentless efforts to provide the best user experience possible.
Test configurations always involve a large quantity of parameters to setup. In addition, many signals and run logs are saved after each test run. To organize such a large quantity of information and to increase efficiency in the process, EDM is powered by a database structure supporting all types of libraries. EDM software keeps run histories of all tests, which can be searched in a single list. Signals are easily reviewed and compared.
Read moreCrystal instruments created the Data Transfer Tool to provide an easy method for transferring data between different PCs or databases. This standalone tool greatly simplifies the entire process by guiding the user through a simple interface. The setup wizard also provides an intuitive interface for monitoring the transfer process.
Read moreThe iconic London taxi; have you ever wondered where and how it was built? Just a hop, skip and three train rides away from London is the town of Coventry, a metropolitan borough in the West Midlands of England. Motor companies from Coventry have made significant contributions to the British auto industry since 1896. It was the home of companies like Rover, a direct ancestor of present day Land Rover and Jaguar. Triumph and Daimler motorcycles are included as well. The modest yet distinct black taxi cab manufactured by LTI in Coventry is a historic engineering marvel featured in trendy and contemporary London, charming locals and tourists alike.
Read moreExperimental Modal Analysis (EMA) has developed into a major technology for studying structural dynamics in the past several decades. Through Experimental Modal Analysis, complex structure phenomena in structural dynamics can be represented using decoupled modes consisting of natural frequency, damping, and mode shapes. The collection of these modal parameters is referred to as Modal Model. Experimental Modal Analysis is commonly referred to as Modal Analysis.
Read moreCrystal Instruments and Sentek Dynamics highlighted products and solutions for environmental vibration testing at the recent Small Satellite Conference 2017 in Logan, Utah.
The annual Small Satellite Conference provides a forum to review recent successes, explore new directions, and introduces emerging technologies. The conference creates an excellent environment for networking and offers the opportunity to launch new, innovative, and low-cost technologies.
Read moreSine tests are performed on a variety of modes to test the DUT. In a Swept Sine test, the DUT is subject to a range of frequencies, one frequency at a time. The response obtained is filtered using a tracking filter centered on the frequency of interest.
Once a transfer function is obtained, it is easy to identify the resonance and anti-resonant frequencies of the DUT. For fatigue testing, a Sine test is typically run in a different mode known as a Dwell Sine where the DUT is subject to its resonant frequency until the DUT experiences fatigue. While the DUT is being driven at their resonant frequencies, the resonant frequency of the DUT tends to shift. Due to this phenomenon, yet another variation of Sine test, RTD (Resonance Track and Dwell) is used. In this mode, the resonance frequency of the DUT is continuously checked using the Amplitude or Phase of the response. Through mathematical calculations, a change in the resonant frequency along with the direction of change is determined. The drive output frequency is then modified instantaneously to drive the DUT at its resonant frequency at all times.
The fatigue testing can last anywhere from a few minutes to several hours. The instantaneous display of the time or frequency signals would be less useful under such test conditions and a synopsis of the entire test duration would be most helpful to draw testing conclusions on the DUT.
Crystal Instruments uses Spectrum history signals, a special type of signals plot to conveniently plot a user defined signal property vs. time or cycles on the X-axis. To ensure the best readability and analysis, the plot is enhanced to accommodate the entire test duration even when the test durations run into several days, weeks or months. With the PC memory as the limitation, test durations of several months or even years can be plotted and viewed simultaneously, thus eliminating any necessity to section the data plot.
Read moreToday’s engineering tools are the result of constant software development, but these developments aren’t always best for the end-user. Engineers who are heavily invested in their tools will be reluctant to switch to a new device. In a time where software is constantly changing, people don’t have the time to struggle with new software interfaces. Especially field technicians, whose job is to collect and analyze data, don’t like wasting time getting used to a new software interface. Their job is already complicated, and is only made worse with a complicated measurement device. If their tools are too complicated to use, engineers will look for a simpler solution.
Read moreIntroduction
Experimental Modal Analysis (EMA) has developed into a major technology for the study of structural dynamics in the past several decades. Through Experimental Modal Analysis, complex structure phenomena in structural dynamics can be represented using decoupled modes consisting of natural frequency, damping, and mode shapes. The collection of these modal parameters is referred to as Modal Model. Experimental Modal Analysis is commonly referred to as Modal Analysis.
Structural vibration has been a significant focus for the dynamic testing and analysis group. Whether the object is a turbine blade rotating at high speed, or a bridge sustaining traffic and strong winds, Modal Analysis can be applied to provide insightful solutions.
Comprehensive Modal Analysis includes both data acquisition and the subsequent parameter identifications. From its inception till now, Modal Analysis has been widely applied in mechanical and structural engineering for designing, optimizing, and validating purposes. It has been widely accepted for broad applications in automotive, civil engineering, aerospace, power generation, musical instruments, (etc.), industries.
Read moreMulti-Sine is a new type of Sine test which facilitates multiple sine tones sweeping simultaneously at once. In automotive testing, engine mounted components such as fuel lines, turbos, headers, sensors, heatshield… are all subjected to high vibration levels during their operational life cycle. High cycle fatigue testing of engine mounted components is often done with a standard Swept Sine test. By performing a Swept Sine test, all resonances within the frequency ranges are excited and measured. Since the greatest fatigue damage happens at the excitation frequency and is also potentially high near these resonances, it is important to measure the vibration level at these frequencies. The standard Swept Sine only sweeps one frequency at a time with a single tracking filter. To test for fatigue, multiple sweeps need to be carried out for the entire frequency range at multiple times during a multiple sweeping rate.
Read moreIn 2011, many of us read a startling news report of an experiment conducted by CERN claiming that neutrinos appeared to be traveling faster than the speed of light.
The collaboration of the experiment, called OPERA (Oscillation Project with Emulsion-tracking Apparatus), made headlines with its claim that a beam of neutrinos made the 730-kilometre journey from CERN, Europe's particle-physics lab near Geneva in Switzerland, to the Gran Sasso National Laboratory near L'Aquila, Italy, faster than the speed of light by about 60 nanoseconds. The result defied Albert Einstein’s special theory of relativity, which states this cannot happen.
Read moreDevelopers of driverless and driver assisted instrumentation have many situations requiring perfect hardware performance. One such situation that has become evident to both Crystal Instruments (CI) and Sentek Dynamics is the increased requirement for vibration and shock testing of sensing elements used in autonomous vehicles, including: lidar, video cameras, radio cameras, and GPS computers. CI and Sentek witnessed this trend first hand while working closely with autonomous vehicle designers to provide the very best in vibration testing equipment of autonomous driving instrumentation.
Read moreRandom control is a fundamental vibration testing for various industries and manufacturers of products. The FFT based control algorithm transforms time signals to the frequency domain where analysis, calculation, comparison…average, (etc.) are done. The performance of Random control is determined by how well the FFT describes the system characteristics. Proper spectrum resolution must be chosen in order to avoid missing any desirable observations and to meet the requirement of the control performance.
Read moreModal 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.
Although sinusoidal types of excitation signals are occasionally used for modal shaker testing, these tests are typically performed using broadband random type excitation signals. Among these common excitation types, Pure Random is widely used. The Hanning window is generally applied to alleviate leakage caused by the non-periodic signal.
Another popular excitation type is the Burst Random excitation signal. It gained so much popularity because no window function is required. The requirement is to have the burst length selected so that the response decays enough at the end of each time block data. With this constraint, there will not be any leakage in the measurement and a windowing function is not required.
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.
Read moreThe Vibration Institute’s Annual Training Conference is often referred to as offering ‘second to none’ education in vibration analytics and is considered the place to be for vibration and condition monitoring experts. As such, it has also become an excellent networking opportunity for industry elites, manufacturers, and incoming young professionals. With today’s ever accelerating changes in technology, beyond networking, it is also crucial to stay up to date on vibration analysis techniques with the most capable and usable equipment.
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