TURN-KEY TEST SERVICES
Built to better serve the global aerospace industry, Acoustic Research Systems is the world’s leading full service provider of Direct Field Acoustic Testing services.
Designed with a wide range of customers in mind, ARS can provide a number of acoustic testing services that would typically require multiple vendors to accomplish. Furthermore, we can provide those services on a truly global basis.
Dedicated to Acoustic Research and Direct Field Acoustic Testing
Our passion for developing revolutionary technology is fundamental to all our work. Armed with this reason for existence, and knowing that we could vastly improve upon available technology, we founded ARS to support the advancement of the aerospace community as well as all industries and clients requiring uncompromised acoustic testing capabilities.
Our vision is clear: a steadfast commitment to innovation, rigorously guided by scientific method, and driven by an entrepreneurial approach to everything we do. Our systems break new ground for mission critical testing in the development and implementation of space missions and other fields of industrial and consumer development.
ARS is an extension of who we are as individuals, embodying our commitment to innovation and the absolute pursuit of precision. Fully grounded and clearly focused on how we operate, we have executed on our vision with the ARS NEUTRON acoustic test system, a groundbreaking accomplishment by a truly unparalleled team.
- Turn-Key Test Services, where ARS brings a properly sized and configured direct field acoustic testing system to your facility and our highly trained engineers perform the test in conjunction with your team. Since our solution is significantly simpler and more powerful than existing direct field acoustic testing systems, customers can expect shorter setup times, less shaping runs, and more accurate results at with better uniformity than previously thought possible.
- Full-Service Long-Term Leasing, where ARS can supply an appropriately sized turn-key direct field acoustic testing system, as well as on-site training and commissioning, for a given length of time in order to support a specific project or program.
- Installed System Sales, where ARS works with the customer to determine their needs for direct field acoustic testing capabilities, and then delivers a turn-key direct field acoustic testing solution for the customer to own and utilize at their facility. Our systems are designed to be intuitive to use and safe to operate, so that customers can feel confident they’ll get many years of optimal results from their investment.
- Reverberant Chamber Augmentation, where ARS can supply from our catalog of proprietary solutions to create, enhance, or even retrofit existing reverberant chambers with increased SPL output capabilities, as well as high-resolution control beyond the highest frequency most typical nitrogen-driven devices can produce.
WHAT IS DIRECT FIELD ACOUSTIC TESTING?
A scientific method using extremely high levels of sound waves1 (pressure) to simulate a harsh acoustic environment that an object must survive. Since sound waves are vibrations traveling through air, acoustic testing uses sound waves to vibrate an object and simulate the environment it might encounter during launch in the nose-cone of a rocket.
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Rocket launches are violent due to propulsion and aeroacoustic noise2 creating a lot of vibration.
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The payload or cargo being carried in the rocket is subject to these vibrations and needs to be tested to ensure that it will survive the trip.
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One way to simulate the sound and vibration of a launch is to use a system of very powerful purpose-built acoustic devices. Acoustic devices (NEUTRON3) very specifically and precisely around the test object. The number of NEUTRON’s will be determined by the size of the object.
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Microphones4 are precisely placed in the test circle to measure the accuracy of the sound field.
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The acoustic devices are then connected to amplification5 and a computer that functions as a control source6.
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Accelerometers7 are placed on the test object that will measure exactly how the test object responds to being stimulated by intense vibrations from the acoustic energy.
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Using specialized software8, the computer will generate noise signals that emulate the launch experience from a specification of the rocket the test object will ride on. The NEUTRON System will generate specific sound field tones9 at an increasing volume for a specified period. The sound waves will create sound pressure levels so high that it will vibrate the object very similarly to what would take place on the rocket.
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During the test, the control system will record all the measurements from the sensors matched with the sound pressure10 levels from the microphones, producing a set of data11 that the engineers can review and evaluate the test object.
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The engineers will be able to either certify that the object has cleared their test specification and moves to the next phase of testing or to manufacturing to make necessary adjustments, then test again. Once an object is certified for launch, it’s off to its intended use.
TECHNICAL INSIGHTS
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Sound wave - A sound wave is the pattern of disturbance caused by the movement of energy traveling through air, water, or any other liquid or solid as it propagates away from the source of the sound. The vibration disturbs the particles in the surrounding air; those particles disturb those next to them, and so on. The pattern of the disturbance creates outward movement in a wave pattern, like waves of seawater on the ocean. The wave carries the sound energy through the air, in all directions and less intensely as it moves farther from the source.
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Aeroacoustical noise - Aeroacoustics is a branch of acoustics that studies noise generation via either turbulent fluid motion or aerodynamic forces interacting with surfaces. A notable example of this phenomenon is the Aeolian tones produced by wind blowing over fixed objects. In this case the wind passing over the surface of a rocket. This noise will generate sound waves that will vibrate the items inside the rocket.
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NEUTRON Acoustic Testing System - The NEUTRON System is an ultra-high powered Loud Speaker System that was built from the ground up with the sole purpose of being used for acoustical testing. The NEUTRON’s produce extremely high acoustic output with exceptional field uniformity, to be far more accurate and efficient than typical concert speakers when attempted to be used for the same application.
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Test mics – Precision test microphones are placed within the test circle to measure that the acoustic field matches the specification provided by the customer.
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Amplification - A series of powerful amplifiers are connected to the speaker system to power each speaker. Since the NEUTRON system was designed from the ground up, we use one amplifier per speaker connected with a single cable to facilitate exceptionally efficient and accurate system connections.
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Control source - The control sources are individually sourced uncorellated noise outputs driven by the control hardware through application-specific hardware.
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Accelerometers - Are a sensing device used to measure the motion or vibration of the object that it is connected to. The sensor will transmit the recorded data back to the control computer in time sequence with the customers specification.
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Control software – The control software will run the specification sequence provided by the customer and send an audio signal to the loudspeakers that will emulate the sound pressure levels of a rocket launch.
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Tones / specifications – Non-repeating random noise with a Gaussian distribution. Shaped to meet the customer’s target specification by the manual setting of 1/3oct wide SPL target bands, and by the automatic equalization of the system in real-time by the controller during acoustic testing to ensure the output of the acoustic testing system meet’s the customers pre-set target SPL levels in each 1/3oct band.
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Sound pressure - Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone, and in water with a hydrophone.
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Report data – The control software will also receive and record the time-based microphone and accelerometer signals generated by the system, based on the customers specification. This data is plotted and is visible to the test engineers to review the initial performance of the test object during the test, and additional detailed post-processing is conducted following the test.
CONTACT US
If you are interested in learning more about our groundbreaking new designs, or would like to know how an ARS acoustic test system could work for you, please contact us.