795. The Impact of Computer Aided Design on Mass Property Engineering

Paper

Abstract

The rapid growth of Computer Aided Design (CAD) and its adaptation to the engineering process are producing a dramatic impact upon methods of design and are resulting in a breaking down of interdisciplinary boundaries. Formerly, computers have been used extensively by the engineer in the conventional role of performing mathematical operations (design analysis) on specified designs pertaining to his technology problems.
CAD is larger than mere design analysis, it is an approach wherein the computer is allowed to participate in the mainstream of the design process to provide useful engineering data to assist the engineer in his decision-making processes. CAD, in its operation, makes use of any or all of the available automatic processing equipment to provide varied and appropriate engineering information and data displays at any or all phases of the engineering process. Engineering, in this context, infers the total technical activity required to translate the customer’s system requirements (specifications and constraints) into a detailed technical description and analytical verification of the end item ready for transmittal to the customer. CAD is of itself a new technology, used in totally different fields of design activity.
The CAD process can be used to assist the engineer by performing repetitive calculations and re-analysis, providing retrieval and display of pertinent design information, performing tradeoffs at the system, subsystem and component levels, and evaluating the effects on design of modification and constraints due to changes of design criteria and environment, manufacturing limitations and constraints, and selection of concepts, materials, and production methods. An obvious advantage of the CAD process is in using the computer to provide a tool for the integration of subsystems designs to evaluate the total system and to integrate disciplinary efforts.
Design and manufacturing firms are using the computer-engineer link in efficiently performing design automation, generating programmed cutter paths for numerically controlled machines and in conducting automated synthesis. This last activity uses the computer to develop its own efficient design consistent with requirements and optimal with regard to weight, performance or costs.
Synthesis is being used for small structural and electronic components and even for the preliminary design of large aerospace systems. The automated system engineering approach has resulted in a crossing-over of the technology discipline boundaries. This new automated field is performing the system integration function which, in the past, was performed, in part, by the mass property engineer and his weight bookkeeping. Therefore, the mass property profession must be cognizant of the elements of CAD, its status in both government and industry, trends indicating future development, and the role that the Society can perform. These items, as well as the ensuing benefits, are discussed in this paper.