Evolutionary Design of a Customer Activated Terminal: A Case Study

Abstract

The process of designing a customer activated terminal (CAT) is described. A CAT is a self-service computer system that enables people to order food or merchandise, request information, complete banking transactions, etc. The specific application that this paper considers is a quick service restaurant lunch menu. Designers of CATs must assume that many users of such systems have no prior computer experience. One of the goals of this paper is to identify some specific interface design principles that seem to be appropriate for other CAT applications. A second goal is to illustrate how an iterative design process that focuses on user, task, and environmental characteristics can result in a successful product. The paper describes a four phase iterative development approach: data collection, initial design, testing and redesign, and implementation. Activities in each phase emphasize understanding user, task, and environmental characteristics. Several examples of the interface design at various stages of development are presented, and reasons for why design features were altered are discussed. The paper concludes by articulating several principles that apply to the design of CATs.