History of the Accelerometer: 1920s-1996 - Prologue and Epilogue, 2006, The

Sound and Vibration, Jan 2007 by Walter, Patrick L

Upon receiving his undergraduate degree from Penn State in 1965, Patrick Walter (right) began 30 years of employment at Sandia National Laboratories in Albuquerque, NM. While on roll, Sandia sponsored his M.S. degree at the University of New Mexico and his Ph.D. degree at Arizona State University.

Dr. Walter's first position at Sandia was as a test engineer in environmental testing, which encompassed shock and vibration. Subsequently, he worked on instrumentation development for flight, field, and laboratory testing. The majority of his tenure was spent managing various test activities. Many of these management assignments ran concurrently and included: experimental mechanics, test facility development, mass properties, transducer calibration, measurement consulting, telemetry component development, telemetry system packaging (including "bunker busters"), and inertial test system development. Later in his career he managed a rocket launch facility in Kauai, HI and also developed launch systems for flights from Sandia and NASA operated facilities. His last assignment involved establishing a program at Sandia under contract to the Federal Aviation Administration to enhance the structural inspection of aging transport and commuter aircraft.

In 1995, Dr. Walter joined the engineering department of Texas Christian University and subsequently served an interim period as Department Chair. At TCU, Dr. Walter has developed the solid and structural mechanics laboratories as well as the electro-mechanical design sequence. Included among the companies that have provided annual support for this design sequence are: Lockheed-Martin Aeronautics, Bell Helicopter Textron, Alcon Laboratories, U.S. Army Engineer and Development Center Waterways Experiment Station (WES), Aberdeen Proving Grounds (U. S. Army), and PCB Piezotronics. In 2001 TCU's Design Laboratory won first place nationally in a competition sponsored by Design News and ANSYS among all universities.

Through TCU Dr. Walter also teaches a continuing education program in Measurement Systems Engineering, which has been presented throughout the U.S., Canada, and overseas. In 1996 he established Test Measurements Engineering, a technical consulting firm in measurement system design focused on the aerospace and defense community. Since 2003, concurrent with his TCU responsibilities, he has been extensively associated with PCB Piezotronics, Inc. as their Measurement Specialist.

Dr. Walter has numerous publications and has served and chaired DoD and DOE committees. He is a member of ISA (25 years, Aerospace Systems and Test Measurements Divisions), Society of Experimental Mechanics (also 25 years), and American Society of Engineering Educators (Instrumentation Division). He is also a Contributing Editor on the masthead of Sound and Vibration. He is a licensed Professional Engineer in the state of New Mexico.

Prologue

Researching and writing the following article ten years ago (1996) was professionally very satisfying. The fact that its accuracy has not been challenged during that time period indicates that it should continue to withstand the test of time for validity. It is a pleasure to report that all eleven individuals in the photo of Figure 6 are still alive and healthy, and seven are at least still partially involved with accelerometer technology. The senior member of that group, Walter P. Kistler (age 88), is still actively involved in scientific endeavors. Mr. Abe Dranetz (age 84), who built the first practical, commercial, piezoelectric accelerometer in the United States, remains active in philanthropic affairs. Prof. Emeritus Peter K. Stein (Arizona State University) recently received the Shock and Vibration Information Analysis Committee's Lifetime Achievement Award. Mr. Jim Lally (C.E.O. of PCB Piezotronics, Inc.) recently received the D. J. DeMichele Award of the Society for Experimental Mechanics.

I have identified a few, minor, corrections or additions to the article that I wish to identify: (1) Dytran was described as a "PCB spin-off." More accurately, Mr. Nick Change, Dytran founder, began work at Kistler Instruments in 1965, held managerial positions at PCB from 1971-1978, rejoined Kistler for a year, and then initiated Dytran in September 1980. (2) The contributory work of both Mr. Verne Siegel and Mr. Bob Lally in integrating MOSFET technology into quartz sensors within Kistler Instruments in the mid-1960s should have been mentioned as it assisted the Kistler patent filing. While the genesis of this work may have been in an earlier U.S. patent 3,294,988, the work at Kistler Instruments in the 1960s clearly moved this technology into the piezoelectric transducer marketplace. (3) A 1967 paper by Mr. Bob Lally,18 PCB co-founder, is cited as it provides an early technical description of this MOSFET technology, as well as additional historical references. (4) Clevite Electronic Components division of Clevite, Inc., (previously Brush Development then Brush Electronics) Cleveland, OH, was a respected manufacturer of piezoelectric accelerometers in the late 1950s and early 1960s that subsequently vanished. (5) Prof. Wayne G. Brown, University California Berkley, performed the earliest documented work using a Hopkinson bar to calibrate accelerometers in the early 1960s.21 This work was transferred through Lawrence Livermore National Labs to Bob Sill, then at Endevco, now at PCB, who developed it into a commercial calibration standard.