The use of system dynamics in manufacturing systems engineering

Abstract

This paper considers the characteristic dynamic behaviour associated with basic manufacturing system designs. In studying such systems the focus will be on three fundamental flows: orders; materials; and information. Of specific interest is the influence of these flows on scheduling decision rules based on stock levels and/or product order rates, as well as how information is passed through the system. Thus it is the optimum combination of feedforward and/or feedback flow paths in a manufacturing-system design which is being sought. This paper will propose a 'middle ground' between two categories of technique used when considering dynamic behaviour - i e, building models using continuous computer simulation packages and alternatively using models capable of mathematical solution. It is proposed that mathematical models, of limited complexity, can provide the necessary insight to guide the design and appraisal of live system models built with a continuous computer package. The paper concludes by developing the idea that a generic application in the study of scheduling strategies for live manufacturing systems.

Controller Design for a Class of Delayed and Constrained Systems: Application to Supply Chains

“…Our concern focused on the use of the control theory methods, which provide an analytical and formal framework and allow a structural approach to handle the supply chain issues. Indeed, since the pioneering works of Simon [18], who was the first to use Laplace transform to analyze a supply line dynamics, numerous investigations followed, such that [6,24,5,22,15,26], in which the supply chain was modelled using block diagrams and controlled through feedback structures. These investigations lead to the well-known Automatic Pipeline Inventory and Order Based Production Control System (APIOBPCS) models and their variations [10].…”

“…Being given a system of the form (1), with a control law of the form (5) and suitable initial conditions, such that the conditions (12), (13) and (14) are verified, then the following holds true…”

Stability analysis of constrained inventory systems with transportation delay

“…Towill (1982) presented a model named Inventory and Order Based Production Control System (IOBPCS) in the form of a continuous time, Laplace Transform block diagram. Edghill and Towill (1989) introduced a variable inventory target to the basic IOBPCS model, creating the VIOBPCS (Variable Inventory and Order Based Production Control System) model. John et al (1994) proposed an Automatic Pipeline, Inventory and Order Based Production Control System, or APIOBPCS by adding work-in-process (pipeline inventory or supply line) information feedback into the production target decision process.…”

Assessing the impact of e-business on supply chain dynamics

“… Simulation and system dynamics; this approach was advocated by Forrester [20] as a method of investigating the dynamical effects in large non-linear systems without resorting to complicated mathematical control theory based models [21]. Simulation approaches alone suffer from being cumbersome, time consuming and only provide limited insight [22], but they do have the advantage of being able to model non-linearity's whilst avoiding complicated mathematics.…”