|7:30 am Registration
8:10 am Introduction
Tutorial Chair: Hadi Navid, The Johns Hopkins University - APL
Session 1 - Direct Field Acoustic Testing (DFAT)
Instructors: Dann Hayes & Wes Mayne
MSI DFAT Services
This course will present methodology and concepts necessary for the successful development and execution of a Direct Field Acoustic Test (DFAT). Material covered will include a review of the environmental characteristics, DFAT terms and definitions and some background and history of the development of the process and the current state of the art. Details on preparation and execution will include facility logistics and handling, configuration and layout, sound generation equipment, control and data processing procedures and a review of the results to be expected from a successful test. The session will conclude with a summary of recommendations and discussion of some special topics relating direct and reverberant testing as well as a hands-on demonstration.
Daniel Hayes is a graduate of Purdue University with a BS degree in Acoustical Engineering. He currently works at MSI-DFAT Services where he is involved in the design and support of the DFAT system. He also works on sound system/speaker design and engineering live shows.
Wes Mayne III has worked with test facility development and testing for over 30 years, including many high-intensity acoustic test facilities around the world. Wes currently works for MSI-DFAT Services supporting both actual DFAT tests and the development of vibroacoustic modeling for DFAT.
Session 2 - An Overview of Modal Analysis
Instructors: Dr. Peter Avitabile, PE
Director, Modal Analysis and Controls Laboratory
University of Massachusetts Lowell
Modal analysis is an extremely powerful tool used for identifying dynamic characteristics for a variety of different structures and systems. This tutorial session is intended to provide a very broad overview of the modal test process with simple illustrations of the process from test data acquired to reduction of data obtained. Some applications directed towards additional uses of the modal data are also presented.
Dr. Peter Avitabile received his D. Eng., from University of Massachusetts Lowell and has over 40 years experience in design, analysis, finite element modeling and experimental modal and structural dynamic testing. Main area of research is structural dynamics specializing in the areas of modeling, testing and correlation of analytical and experimental models and integration of analytical and experimental techniques. Research, testing and consulting performed for automotive, aerospace, defense and computer/consumer related areas. Written over 200 technical papers and given numerous seminars in the areas of experimental modal analysis, structural dynamics, vibration fixture design, and modeling and correlation.
Session 3 - Multi-component Force Measurement & Signal Conditioning
Instructors: Bill Zwolinski
Piezoelectric sensor technology provides robust dynamic measurement
capabilities as well as quasi-static measurement over a wide range of operational
conditions. At the heart of higher performance operation is innovative sensor design as
well as use of piezoelectric materials including quartz and a proprietary crystal
technology—Piezostar as well as signal conditioning with charge amplifiers. The goal is
to extend performance in areas such as sensitivity, frequency response, resolution and
accuracy. Practical considerations for instrumentation to measure reaction
forces/moments is discussed relative to applications such as Micro-vibration, Cryo-
Cooler Vibration, Thrust Stands, Reaction Wheels, Environmental considerations such
as Cryo/Vacuum/Flight, Impact, and Force Limited vibration. Instrumentation
considerations include, sensor geometry, preloading, bending moment, crosstalk,
sensor mounting/alignment, resonance, noise, rangability, scalability, cabling and
signal conditioning with extended filter capabilities and digital/analog output.
Bill has been Product Manager, General Manager-US Technology Center, Product Director, Head Test and Measurement at Kistler Instrument Corporation. He received his M.Sc.EE, from University of Connecticut and his MBA in Technology Management and Marketing, from University of Phoenix.
Session 4 - Vacuum Generation for Space Simulation Chambers
Instructor: Edward Ho
Pfeiffer Vacuum Inc.
This tutorial will provide an overview of pumping technologies used in vacuum generation for
space simulation. Generation of vacuum and the measurement of vacuum level encompasses
many topics which need consideration. Historically, large vacuum systems were dominated by
diffusion and cryogenic pumps, however, advances in technology have brought turbo pump and
dry rough pump technologies to the forefront. The benefits of turbo pump technology and
practical issues dealing with large space simulation chambers need to be understood.
During the tutorial we will compare the pros and cons of diffusion, cryopump, and turbo pump
technology in creating high vacuum for large chambers. In particular, there will be focus on
turbo pump technology and their operational requirements which includes properly sizing the
pumping system. We will also address how to properly maintain turbos and discuss possible
service issues such as long down times between pump operation. Finally, we will investigate the
area of modern vacuum measurement, analysis and leak detection.
Edward Ho received his Bachelor of Science degree from the University of California, Berkeley
from the Dept. of Chemistry in Chemical Engineering. Subsequently, he spent some years at
Ames Research Center working for NASA in the Regenerative Life Support Group developing
materials for CO2 adsorption. He has been with Pfeiffer Vacuum for 17 years with a focus on
Question-Answer Discussions to Follow Each Session