FLEXIBLE MANUFACTURING SYSTEMS

By

SUDHIR REDDY S. V.R

M. Tech (CAD/CAM)

09311D0412

SOFTWARE SPECIFICATION AND SELECTION

For software to be effective, it must meet the requirements that are defined based on its purpose and how well it does its intended job. The requirements can be expressed in the form of absolute and functional specifications. These specifications provide a basis for detailing requirements for the software and can be used as a checklist against which various alternatives can be evaluated.

I. ABSOLUTE SPECIFICATIONS:

1. Detailed Specification:-

a) FMS Characteristicsb) Program Codec) Computer Hardwared) Production Capacity

2. Effective User Interface:-

a) Minimal Training Requirementsb) Multi User Capabilityc) Fast Execution / Response Time

3. Software Design:-

a) Modular Structureb) Design for Growthc) Interface to Other Software

4. Effective Verification & Test

5. Effective Documentation:-

a) Training Manual / Tutorialb) User-interfacec) Programmer Reference

II. FUNCTIONAL SPECIFICATIONS:

1. Deliverables versus Cost:-

a) Purchase Package

b) Tech Support & Software Service

c) Availability of Source Code

d) Documentation

e) Training

f) Hardware & Support Equipment etc.

2. Quality:-

a) Vendor Credibility (Including on-time delivery)b) Reliability

3. Programming:-

a) Programming Languageb) Structure of Programc) Error Recoveryd) Securitye) Diagnostic aidsf) Access to Databaseg) Interface to Other Applicationsh) Graphics Display

4. Controlled Applications:-

a) CNC Part Programb) Traffic Controlc) Shuttle Controld) Tool Controle) Quality Control

5. Management Applications:-

a) Schedulingb) Production Controlc) System Monitoring

6. Reports:-

a) Management

b) Operational

FMS TRENDS & CONCLUSIONS

Flexibility in FMS provides an opportunity to capitalize on basic strengths of a company to ensure long term leadership in manufacturing cost, products and service to customers.

Implementation of FMS involves development of various manufacturing concepts from which a few specific alternatives are selected and then evaluated so that a single alternative can be selected and implemented.

In FMS, the cost of capital equipment and its supporting software will be a major driving factor as well as limiting factor in the ability of a company to remain competitive in the world market.

In addition to a very detailed business analysis, a comprehensive technical analysis of the system must be made. For example, the expanded manufacturing systems will incorporate new techniques and processes. In machining and spindle probes and spindle load monitoring are now common. Adaptive controls, tool life monitoring, broken tool detection, improved pallet positioning techniques and spare tool selection, all will come into common use in these large systems (FMS). Each technology brings with, it the need for software to monitor and control the processes and operations.

The sensitivity of various alternatives to change business conditions must be carefully evaluated. What if the forecast for a particular product materialize faster or slower than anticipated?

Finally, since manufacturing systems will be provided by vendors with varying degrees of experience and capability, it is important to find and develop intelligent ways of working with vendors to develop basic concepts and turn basic needs, goals and strategies of the business to equipment and/or software suppliers in such a way that concepts directed towards the particular needs of company can be developed

APPLICATIONS OF SIMULATION SOFTWARE

In numerous studies, Simulation is used a technique for analyzing and evaluating an existing or proposed manufacturing systems.

Earlier, Simulation studies design phase of a manufacturing system implementation which tends to focus on equipment and material handling requirements.

Caruso & Dessouky (1987) developed a Simulation Model of a proposed FMS system which is used in assembly of Instrument Panels.

Simulation models of existing systems frequently are used to test different control and dispatching strategies.

Godziela (1986) uses Simulation to evaluate performance of proposed system to support certain levels of production activity. Falker and Garlid (1987) use Simulation to justify implementation of an FMS.