Design Problem Solving: A Task Analysis

Design problem solving is a complex activity involving a number of subtasks and a number of alternative methods potentially available for each subtask. The structure of tasks has been a key concern of recent research in task-oriented methodologies for knowledge-based systems (Chandrasekaran 1986; Clancey 1985; Steels 1990; McDermott 1988). One way to conduct a task analysis is to develop a task structure (Chandrasekaran 1989) that lays out the relation between a task, applicable methods for it, the knowledge requirements for the methods, and the subtasks set up by them. I propose a task structure for design by analyzing a general class of methods that I call proposecritique-modify methods. The task structure is constructed by identifying a range of methods for each task.