The 3-hour Webinar course will start with the basics, defining such terms as “G”, “g”, “GRMS” and “G-Force”.  We will explain the physics of shock and vibration in understandable terms. At the end of this course the student will be able to clearly understand shock and vibration, its terms, how tests are specified, and have the capability to apply software as a test aid. This course provides excel based software to aid the student in quickly learning shock and vibration fundamentals.  With the DfRSoft Shock and Vibration Software, the student will be able to specify shock tests and perform a number of analyses. Every section below will have many examples to aid the student.

Shock Test and Analysis

The course will overview the different types of mechanical shock and test methods, including drop shock and electro-dynamic shock pulse and Shock Response Spectrum (SRS) testing (and how these tests are specified). The software will help the user specify drop height, Gs, pulse durations and the need to calibrate the equipment.

Constant Acceleration

We will overview constant acceleration physics and testing. The student will understand the basics terms (RPN, Gs, and equipment radius) and how to specify this test and what key elements are needed to perform a successful constant acceleration test.

Sine Vibration

Sine vibration fundamental and physics will be explained in understandable terms, including natural and forcing frequency, damping, Q, and resonances. We will detail a vibration test system’s set up. The student will be able to use the software to understand vibration testing and the interrelationships between sine amplitude, frequency, velocity and acceleration. We will discuss circuit board and equipment sine search resonance track and dwell testing, definition of an octave, sweep rate, graphical sine estimation of Q from the data and how to estimate if the resonance is too large and requires damping. How best to track a resonance using the phase shift method during a resonance scan. The software will help the student understand the proper octave sweep rate for resonance searching and key locations to place an accelerometer. We will introduce S-N fatigue curves and the use of Minor’s rule.  A discussion on time compression will follow for the vibration acceleration model and how to use it for fatigue life testing. Numerous examples, problems and solutions are provided.

Random Vibration

Here we will introduce why we do random vibration, how to understand the frequency domain and the test specification, including common tests that are specified. The student will be able to estimate from the G2/Hz Power Spectral Density (PSD), the G-level content for both simple and complex spectra.  An overview of basic random as well as sine on random, random on random, tri-axial and angular vibration testing (along with angular fixture use) will be discussed. How to use random vibration to estimate Qs observed in the PSD spectra will be explained. As well, the random vibration acceleration model for time compression will be exemplified using the software and how it differs for sine vibration and its use for fatigue life estimation in X, Y, and Z directions. Accelerometer use will be overviewed for random vibration.  Repetitive shock will be overviewed which is used in HALT testing and how this spectrum differs from random vibration. What are the strengths and weakness of repetitive shock? When to use HALT versus electro-dynamic (ED) random vibration testing?

Target Audience – Supervisors, test engineers and technicians.

Required Tool from DfRSoft.com

DfRSoft.com software module requires Excel 2003 or higher.  This will be supplied for free.

Instructor

Dr. Feinberg has a Ph.D. in Physics and is the author of the book, Design for Reliability.  Alec has provided reliability engineering services in all areas of reliability and on numerous products in diverse industries that include solar, thin film power electronics, defense, microelectronics, aerospace, wireless electronics, and automotive electrical systems.  He has provided training classes in Design for Reliability, Shock and Vibration, HALT, Reliability Growth, Electrostatic Discharge, Dielectric Breakdown, DFMEA and Thermodynamic Reliability Engineering.  Alec has presented numerous technical papers and won the 2003 RAMS Alan O. Plait best tutorial award for the topic, “Thermodynamic Reliability Engineering.”