Given the strong drive to achieve a short time to market with strongly innovative products many companies face a structural dilemma with respect to product reliability. Due to the increasing complexity of products and the way they are applied, longer and increasingly complex tests are required to establish (and if necessary optimize) the reliability of these products. On the other hand, due to the strong pressure on "Time to Market" in many design processes, this time is simply not available. Therefore alternative strategies have to be developed. This paper addresses a strategy to replace reliability tests by reliability optimization based on computer simulations. Although the development of adequate models is, in a practical situation, quite complex and time consuming as well, once these models are available they can lead to considerable shorter product development cycles.
INTRODUCTIONReliability of consumer products has always been a big concern for manufacturers. Customers expect to use products over a certain period of time without any problems. This leads to the problem of addressing the risks involved in perceived quality and reliability levels and if possible control or reduce them at the design phase. In the early phases of the design development, actual field information of the product function will not be available. Therefore, predictive models for the product design must be developed in order to allow an assessment of its behavior in the field. It is only through this that it is possible to realize the early identification and resolution of potential quality and reliability problems. In this paper a new concept for designing for reliability will be presented and illustrated by a simulation example. First a brief discussion on the purpose of the paper will be presented, followed by the background of the research. In the next part a literature review of existing methods in reliability engineering will be discussed, followed by the problem discussion. The next section will describe the general line of research emphasizing on theory and the approach used. The theory developed is tested using simulation techniques. Then the results and conclusions are explained followed by a research discussion.2.0 PURPOSE OF RESEARCH Reliability theory deals with the interdisciplinary use of probability, statistics, and stochastic modeling, combined with engineering insights into the design and the scientific understanding of the failure mechanisms, to study the various aspects of reliability [BLI00]. This is also very true for the concept as will be discussed in this paper.The proposed concept basically tries to solve a reliability improvement-optimization problem through analysis and modeling of degradation of the critical designable parameters or design parameters (= physical product parameters that can be influenced by the designer) and associating it with the degradation of the performance characteristic under study, where performance characteristic can be defined as a measure expressing how good a product fulfils its...