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Engineers and managers involved with product development are continually challenged to reduce time to market, minimize warranty costs, and increase product quality. This results in less time for testing, which means the need for effective accelerated test procedures has never been greater. Accelerating your testing program sounds great, but how do you begin? This course starts by taking a look at statistical models for reliability testing. It looks specifically at how sample size and testing timeframe affect what you’re able to do versus what you'd ideally do with more time and money.

Using individual accelerated failure mode tests (such as HALT and FMVT®) has provided useful information to practitioners in the past. However, the combining of two or more techniques has shown significant improvement at providing fast failure mode information combined with life expectancy and field failure rate information. This paper will give examples of combining accelerated failure mode tests with two or more life prediction techniques to leverage the information gained from the testing. A rationale for how to choose and combine tests will also be discussed.

Failure mode identification test such as Failure Mode Verification Testing® (FMVT), Highly Accelerated Life Testing (HALT) and Multiple Environment Over Stress Test (MEOST) have provided a solid means of identifying failure modes quickly. Many experts in these different methods have asserted that making life predictions from these tests will eventually be possible. This paper will explore the current state of making those correlations and detail several methods that have been successful in providing correlation between failure mode testing results and field life data. The short-term and long-term potential for life prediction and population synthesis will be discussed.

Given the myriad of testing options available and the reams of testing specifications that exist today, how do you know what testing process should be used for a given component or system? What information is needed and what is the most efficient means of getting the desired results. This paper compares two accelerated testing methods with more traditional validation tools and examines the relationship between the information goals, the process used, the anticipated failure modes, and the equipment needed. A decision making algorithm will be proposed.

By using the DFMEA to design an accelerated test that will take one or two days the design engineer and the validation engineer can determine quickly whether the design has successfully avoided key failure modes and unanticipated failure modes or if redesign is needed. This provides better continuity in the design iteration process. Once the design has been proven to be free of design related failure modes the validation can be conducted.

HALT to FMVT details Entela, Inc.'s initial contact with Highly Accelerated Life Testing and this companies efforts to apply the technique to mechanical systems. Technical problems encountered are explored and some solutions noted. The technical and market forces moving the automotive industry toward Highly Accelerated Life Testing and Failure Mode Verification Testing are out-lined. Several successful examples of FMVT are given with comparison to the traditional testing technique. Some results of a Finite Element Analysis of how HALT and FMVT works are also presented. Highly Accelerated Life Testing has been used in the electronics and aerospace industry for many years. Applying the techniques of HALT to mechanical systems in the automotive industry required investigating how and why the technique worked and providing for the differences in products under test.

Failure Mode Verification Testing (FMVT) is a highly accelerated test method that uncovers design weaknesses in mechanical products. The goal of the technique is to uncover design inherent failure modes in a very short amount of time by applying a broad range of stress patterns at elevated levels. The FMVT technique is an application of the Highly Accelerated Life Test (HALT) methodology. HALT has been used in aerospace and electronics industry for many years.3 FMVT provides for a measure of the design's maturity but does not determine the life expectancy or reliability of a product. FMVT has been used on mechanical systems by adapting the traditional HALT frequency ranges, and other stress sources to mechanical systems. FMVT has been successfully applied to several automotive mechanical products.