Tech 149: Unit 3

Computer Integrated Manufacturing Technology: (CAD & CAM)

Data Communication Processes in CAD/CAM

In CAD/CAM:• Data is created• Data is generated• Data is simulated• Data is transformed• Data is translated• Data is cleaned

• Data is stored• Data is communicated• Data is manipulated• Data is managed• Data is analyzed• Data is retrieved• Data is interpreted

Chapter 4: Design Automation: CAD

• CAD is the application of computers and graphics software to aid or enhance the product design from conceptualization to documentation.

• Computer-aided drafting (CAD) automates the drawing or product documentation process.

• Computer-aided design (CAD) is used to increase the productivity of the product designers.

CAD System Capabilities Include:

• Stand-alone PC and RISC-based CAD workstations at each engineering and design drafting location

• The ability to share part data and product information with every station in the system

CAD System Capabilities Include:

• Access to part data files from the mainframe computers on the network

• Shared peripheral resources such as printers and plotters

• Concurrent work on the same project from multiple workstations, one of the reasons our team project needs a web site or data base.

Basic CAD System Includes:

• Keyboard• Input devices• Output devices

Application of CAD to Manufacturing Systems

• Concept and repetitive design (product, fixtures, gauges, pallets, mold, etc.)

• Drafting• New product development management

(PDM) and the Internet

Chapter 5: Design Automation: Computer-Aided Engineering Computer-aided engineering (CAE) is the

analysis of the engineering design using computer-based techniques to calculate product operational, functional, and manufacturing parameters too complex for classical methods.

  CAE also provides productivity tools to aid production engineering area by providing software to support group technology (GT), computer-aided process planning (CAPP), and computer-aided manufacturing (CAM)

Design for Manufacture and Assembly (DFMA)

   DFMA is any procedure or design process that considers the production factors from the beginning of the product design.

   Originated from producibility engineering (DFM) and design for assembly (DFA)

DFM

DFA

Computer-Aided Engineering Analysis

       Finite-element analysis (most frequently used)

       Mass property analysis

Computer-Aided Engineering Evaluation

        PrototypingRapid prototyping techniques:1) Stereolithography2) Solid ground curing3) Selective laser sintering4) Three-dimensional printing5) Fused-deposition modeling6) Laminated object manufacturing

Group Technology (GT)

   GT is a manufacturing philosophy that justifies small and medium-sized batch production by capitalizing on design and/or manufacturing similarities among component parts.

Group Technology

Prismatic and round parts

D

D D

D

D

D B

B B

B

B

B

T

T T

T

T

T M

M M

M

M

M

Group Technology (GT)

Coding and classification:1)Coding is a systematic process of establishing an alphanumeric value for parts based on selected part features.2)Classification is the grouping of parts based on code values3)Coding and classification in GT are highly interactive because the coding system must be designed to produce classified groups with the correct combination of common features.

Group Technology (GT)

In GT production cells, groups of different machines are identified based on their ability to produce families of parts.

Computer-Aided Process Planning (CAPP)

• Consistent and correct process planning requires both knowledge of the manufacturing processes and experience.

• Two automation techniques are called variant and generative process planning.

Computer-Aided Process Planning (CAPP)

  The CAPP variant approach uses a library of manually prepared process plans in the database and a retrieval system to match components on new parts to existing process pans of similar components.

  The CAPP generative approach utilizes a process information knowledge base that includes the decision logic used by expert human planners.

Computer-Aided Manufacturing (CAM)

  CAM is the effective use of computer technology in the planning, management, and control of production for the enterprise.

  One of the major applications of CAM is in CAD/CAM where the part geometry created with CAD in the design engineering is used with CAM software to create machine code (NC/CNC) capable of machining the part.

  Production and process modeling.  Production and process simulation.  Production cost analysis.

Design and Production Engineering Network

Demands:  A common database for enterprise information

flow  Easy, accurate and instantaneous movement of

part geometry files and product data between departments

  An enterprise network is a communications system that supports communications and the exchange of information and data among various devices connected to the network over distances from several feet to thousands of miles

Group Technology (GT)

Reasons for adopting GT• Benefits of GT

– Benefits in product design– Standardization of tooling and setup– More efficient material handling– Increased economies of batch-type production– Easier scheduling– Reduced work-in-process and lead time– Faster and more rational process planning

Distributive Numerical Control (DNC)

• Conventional system• CNC “behind the reader” system• DNC minicomputer system