Original Press Release
U.S.-led International Standard Leads to Improved Shock Tests
Press release date: April 12, 2007
A new standard published by the International Organization for Standardization (ISO) can be used to determine how various high-tech systems-from computer components to aircraft frames to military vehicles-will respond to shock pulses associated with earthquakes, explosions, impacts and other mechanical shocks.
ISO 18431-4:2007, Mechanical vibration and shock-Signal processing-Part 4: Shock-response spectrum analysis, specifies methods for calculating a shock-response spectrum, or SRS, by digital means. An SRS graphically illustrates the relative strength of a shock pulse across frequencies.
First used by the U.S. Department of Defense, the SRS was developed in the early 1960's as a means of characterizing both the severity of shock events and the ability of mechanical or electronic systems to tolerate them. They have been widely used to test highly specialized items, including aerospace instrumentation systems and armored vehicles, as well as more broadly applied items, such as hard drives and shipping containers.
In the past, shock tests were generally based on a variety of analog and digital algorithms, which often led to significant variance in results. ISO 18431-4:2007 relies on standardized, well-defined digital techniques so that test results from different laboratories can be reliably compared.
The development of ISO 18431-4:2007 was led by ISO technical committee (TC) 108, Mechanical vibration, shock and condition monitoring, and its working group on signal processing (WG 26). The Acoustical Society of America serves as the secretariat for TC 108 on behalf of the American National Standards Institute (ANSI), the official U.S. representative to the ISO. The National Institute of Standards and Technology (NIST), as convener of WG 26, played an active role in encouraging U.S. industry participation in the technical discussions.
For more information on the work and scope of ISO TC 108, please click here.