A Computer Aided Design System for Product Oriented Manufacturing Systems Reconfiguration

S. Carmo-Silva, A.C. Alves, M. Costa

University of Minho, Portugal

Outline

Motivation

Generic alternative configurations - Definitions

POMS – Product Oriented Manufacturing Systems

    • are systems dynamically reconfigured to best suit the manufacture of a single type of product or a family of similar products at a time

    • in variable product demand markets.

FOMS – Function Oriented Manufacturing Systems

    • referred also as process organization are statically configured systems to suit a large product variety

    • where work flows between functional departments according processing requirements.

    • Usually a number of different jobs, are concurrently manufactured in a complex network of workflows. High interference and production interdependence between jobs exist.

Generic alternative configurations - Attributes

POMS – Product Oriented Manufacturing Systems

    • Fast manufacturing response    Yes

    • High quality of production       Yes

    • High manufacturing resources utilization (Equip.&People)    Yes

    • High throughput rates    Yes 

    • Varying manufacturing capabilities   ?

FOMS – Function Oriented Manufacturing Systems

    • Fast manufacturing response    ?

    • High quality of production    ?

    • High manufacturing resources (Equip&People) utilization    ?

    • High throughput rates    ?

    • Varying manufacturing capabilities   Yes / ?

The generic confıguratıon choice - POMS

POMS - Varying manufacturing requirements ?

    • Fast POMS design-reconfiguration

      • Flexible reusable manufacturing resources (Equip.&People)

      • Movable manufacturing resources (Equip.&People)

      • Easier access to manufacturing resources

        • Internal

        • External

      • Virtual reconfiguration

      • ...

POMS - Varying manufacturing requirements  Yes

 
POMS Design and reconfiguration

 

How to get there fast and well?

    • Computer Aıded Design Systems (CADS) are needed 

CADS for Manufacturing Systems Design 

Existing CADS include one or some of the following restrictions:

    • Unable to deal with overall POMS design

    • Design technique based (ex.: PFA Simplification Tool)

    • Use of generic design tools (TRIZ, Axiomatic Design)

    • Oriented to wide spectrum of manufacturing Systems

    • Not directly addressing POMS design needs

    • ...

A POMS design System

First a methodology

    • The proposed CADS_POMS is based on the GCD methodology

The GCD methodology is structured in three main design stages:

      • Generic Design

      • Conceptual Design

      • Detailed Design

A POMS design system

Second: A computer aided implementation of the design methodology

    • The CADS_POMS -  Computer Aided Design System for Product Oriented Manufacturing Systems

Generic Design

Generic Design
 
 

Conceptual and Detailed Design

CD1_NPG

Main components of CADS_POMS

Main components of CADS_POMS

CADS_POMS data sets and structure

 

  • Fundamental data sets in POMS design

  • Input data windows

  • Structure and relationships between fundamental data sets

  • Machine set selection

Fundamental data sets in POMS design

    • Product data

      • product description

      • Product Structure definition

      • Definition of product operations

      • product operation plan definition (precedence between operations)

    • Generic Operations

    • Processing characteristics for operations

    • Manufacturing Resources data

      • Machines

      • Operators

      • ...

Input data windows

    • Product data input:

        • product description

        • product structure definition

        • definition of product operations

        • product operation plan definition (precedence between operations)

    • Processing characteristics or attributes for operations

    • Machines data input:

      • machines description

      • processing characteristics or attributes allocation

    • Product operations processing characteristics or attributes allocation

  Product data input: product description  

product description

Product data input: Product structure definition

product structure definition

Product data input: Definition of product operations

Definition of product operations

Product data input: product operation plan definition (precedence between operations)

product operation plan definition (precedence between operations)

Product data input: product operation plan graphical representation

product operation plan graphical representation

Definition of Processing attributes

 Processing characteristics or attributes for operations

Machines data input: Machines description

Machines description

Machines data input: processing characteristics or attributes allocation

processing characteristics or attributes allocation

Product operations processing characteristics or attributes allocation

Product operations processing characteristics or attributes allocation

Structure and relationships between fundamental data sets

Fundamental data sets in POMS design and interrelationships

Schematic representation of Machine selection for operations processing

Schematic representation of Machine selection for operations processing

Matching process: Automatic Machine Set Selection for each product operation

Automatic Machine Set Selection for each product operation

Conclusions

  • POMS Design is complex
  • Needs Computer Aid
  • A framework for POMS Design based on the GCD methodology was described
  • The first stage of the CADS_POMS design system development was presented
  • High interaction with a knowledge base implementing methods for system design and evaluation is required in the design process
  • Algorithms, Heuristics, Rules, Mechanisms, Evaluation procedures are used through user interaction and intervention
  • High user interaction is necessary to carryou the design process

Further work is needed

    • To enhance the CADS_POMS for fully implementing the design methodology

    • To fully develop a useful knowledge base for system design

    • To explore the advantages of a Knowledge distributed base

    • To evaluate the viability of

      • independent implementations of CADS_POMS in different companies sharing the same distributed Knowledge base

      • remote or local insertion and availability of new methods in network of computing peers and servers