Technical evaluation of products or alternative designs is a frequent and central activity in engineering design. Conventional quantitative evaluation procedures typically involve some element of subjectivity on the part of the engineer. For example, they are likely to require assignment of weighting factors which define the importance of various design criteria. In this paper, an economic approach is proposed for product evaluation. The evaluation process is based on the whole-life cost/benefit of the design, as assessed from the perspective of the owner or operator of the product. It has the advantage of beeing more objective than conventional approaches, and providing a balanced set of 'weightings' to the various design criteria. The new method is used in this paper to compare four heavy vehicle suspensions. It is also compared with a conventional evaluation method, using weighting factors derived from a survey of vehicle operators. The aim is to investigate the difference in emphasis placed on various evaluation criteria, and the sensitivity of the two approaches to various assumptions in the analyses. The influence of some important factors of vehicle operation, such as service life, operating conditions and suspension parameters, are also investigated. Based on the links of most design issues to cost, it was suggested that cost is the most suitable common metric on which to base design evaluation. Economic weightings were found to be considerably more discriminating that subjective weightings obtained from a survey of transport fleet operators. The survey replies were found to overestimate the importance of capital cost and accident cost, and to underestimate the remaining criteria, such as, freight capacity, fuel consumption, etc. The whole life cost/benefit evaluation method is capable of demonstrating the effect of product life on the choice of suspension, while the tradition approach does not have this capability. The optimum point revealed in the sensitivity analysis to suspension damping could be used for the specification of suspensions by both designers and fleet operators.
Economic evaluation and the design of vehicle suspensions
Wirtschaftlichkeitsbewertung und der Entwurf von Fahrzeugfederungen
International Journal of Vehicle Design ; 31 , 2 ; 125-161
2003
37 Seiten, 14 Bilder, 5 Tabellen, 48 Quellen
Aufsatz (Zeitschrift)
Englisch
Kosten-Nutzen-Analyse , Wirtschaftlichkeit , wirtschaftliche Studie , Wartung , Wartungskosten , Ermüdung , Lebensdauer , Fahrzeugsicherheit , Fahrzeugfederung , Betriebsbedingung , technische Entwicklung , technische Beschreibung , Produktentwurf , Konstruktionsdaten , Bewertungsmethode , Bewertungsproblem , Nutzfahrzeug , Empfindlichkeitsanalyse , Schwingungsdämpfung
Economic evaluation and the design of vehicle suspensions
Kraftfahrwesen | 2003
|Economic evaluation and the design of vehicle suspensions
Online Contents | 2003
|Engineering Index Backfile | 1942
|Interactive Design of Off-Highway Vehicle Suspensions
SAE Technical Papers | 1987
|Interactive design of off-highway vehicle suspensions
Kraftfahrwesen | 1987
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