17 September 2013

Contactless Excitation to Study Composite Panel Vibration Response

Leuven, Belgium, 17 September 2013 – LMS Engineering Services investigates an alternative methodology to obtain higher accuracy transfer function data of composite panels: through contactless excitation. Excitation without any mechanical contact does not influence the structural dynamics of the panel by mass or stiffness loading. This method results in more accurate data that can be used for correlation of a CAE model or to perform modal analysis.

Weight is an important design factor for the automotive industry. The use of more lightweight materials increases the need to understand the noise these new materials generate. Apart from the excitation mechanism, the dynamic characteristics of components are relevant for noise generation. The modal behavior of panels is traditionally obtained by structural FRF measurements with accelerometers and a hammer or shaker. However, conventional dynamic testing of composite materials influences the structural dynamics by mass or stiffness loading. To obtain higher accuracy transfer function data of composite panels in isolated conditions, LMS engineers used a high frequency source to excite a panel without any mechanical contact.

Soft springs dynamically decouple the panel from a supporting structure. The source excites the panel at a specific location. The high noise level of the source easily makes the panel vibrate. A laser vibrometer scans a set of discrete points on the panel to obtain the vibration response of the structure. The result is an FRF set which can be used for correlation of a CAE model or to perform modal analysis.

LMS Qsources – advanced excitation hardware

Covering a wide range of advanced excitation hardware, LMS Qsources seamlessly matches hardware with LMS software. This unique combination highly exceeds current market standards with regard to productivity and data accuracy, and, hence, customer’s expectations.

LMS shakers introduce dynamic excitation and are highly efficient for modal analysis and structural analysis. They benefit from their exceptionally small design without compromising on accuracy, functionality and reliability. The portfolio ranges from miniature shakers so compact that they can be mounted where conventional shakers have no access, to integral shakers that significantly improve the efficiency of testing by eliminating all of the support and alignment work associated with conventional shaker testing, to an inertia shaker designed for the very low frequency range.

LMS volume sources are sophisticated acoustic excitation devices that have been developed to acquire acoustic FRFs at low, mid and high frequencies without disturbing the acoustic sound field with its presence. The integrated volume acceleration sensors give a real-time feedback of the emitted source strength and can directly be used as a reference for FRF measurements without any post-processing.

LMS Qsources excitation hardware is used worldwide by OEMs and suppliers, aeronautics, chemical industries and on large structures such as ships and windmills to improve the acoustic performance on complete system level.

You’ll find more information on the LMS Website on

  • Transfer Path Analysis
  • Qsources portfolio
  • Or contact LMS Engineering Services at qsources@lmsintl.com

About LMS, A Siemens Business

LMS is a leading provider of test and mechatronic simulation software and engineering services in the automotive, aerospace and other advanced manufacturing industries. As a business segment within Siemens PLM Software, LMS provides a unique portfolio of products and services for manufacturing companies to manage the complexities of tomorrow’s product development by incorporating model-based mechatronic simulation and advanced testing in the product development process. LMS tunes into mission-critical engineering attributes, ranging from system dynamics, structural integrity and sound quality to durability, safety and power consumption. With multi-domain and mechatronic simulation solutions, LMS addresses the complex engineering challenges associated with intelligent system design and model-based systems engineering. Thanks to its technology and more than 1250 dedicated people, LMS has become the partner of choice of more than 5000 manufacturing companies worldwide. LMS operates in more than 30 key locations around the world.

About Siemens PLM Software

Siemens PLM Software, a business unit of the Siemens Industry Automation Division, is a leading global provider of product lifecycle management (PLM) software and services with seven million licensed seats and more than 71,000 customers worldwide. Headquartered in Plano, Texas, Siemens PLM Software works collaboratively with companies, delivering open solutions to help them make smarter decisions that result in better products. For more information on Siemens PLM Software products and services, visit www.siemens.com/plm.

Note: LMS Virtual.Lab, LMS Imagine.Lab and SAMCEF are registered trademarks of LMS International or any of its affiliates. Siemens and the Siemens logo are registered trademarks of Siemens AG. All other trademarks, registered trademarks or service marks belong to their respective holders.

This press release was published by LMS International prior to Siemens PLM Software acquiring the company on January 3, 2013.

Główny kontakt

Peter De Clerck
+32 16 384 200