Networked Assembly of Affine Physical System Models

Abstract

Engineering design is evolving into a global strategy that distributes model information through computer networks. This strategy requires companies to provide dynamic models of supplied components. Component models must be assembled to obtain the product dynamic model. Four characteristics are needed. Specifically, models require a unique standard format, the exchange of model information must be executed in a single-query transmission, the models must describe only external behavior, and the assembly process must be recursive. The Modular Modeling Method (MMM) [1], is a model assembly algorithm that satisfies these requirements. The MMM algorithm assembles linear physical systems models with dynamic stiffness matrices. This paper will extend MMM to nonlinear affine behavior. In an affine system, deviations in the inputs and outputs exhibit a proportional relationship, but the outputs of the system are not zero at zero input [2]. The main reason for developing a process to assemble affine systems is the possibility of using this method to assemble general differentiable nonlinear physical system models performing around a constant operating point.