A SET-BASED APPROACH TO SYSTEMS DESIGN

Abstract

A set-based design (SBD) approach is proposed as an alternative to traditional point-based design (PBD) methodologies. SBD is compared to other common engineering, decision-making, and optimization methods to illustrate how conventional methods do not ordinarily embrace set-based thinking (SBT) or SBD methodologies. The predominant features of Toyota's approach are summarized, leading to seven characteristics and two principles required to identify a design approach as set-based. Several Latin hypercube (LHC) sampling strategies and the distinguishing characteristics of each are described for use in creating and refining sets. Methods of set reduction and elimination are introduced, and topics related to engineering reasoning in set reduction, expectations, SBT, when to use SBD, benefits, challenges, and metrics are discussed. Improved SBD process steps are proposed and demonstrated in an unmanned air system (UAS) example. A specific type of LHC is chosen to generate points in the design space, which are then used as inputs into a simulation tool. Approaching the UAS example problem in a set-based way results in more viable options with higher system-level performance for comparable cost than if a PBD approach were used.