Computer Integrated Manufacturing: Principles and Systems
1. Define Computer Integrated Manufacturing (CIM)
Computer Integrated Manufacturing (CIM) is a manufacturing approach that uses computers to integrate and control major activities in product development and production. It connects design, planning, material handling, quality control, and management through a common information system.
Elements of CIM
The major elements include Computer-Aided Design (CAD), Computer-Aided Manufacturing (CAM), Computer-Aided Process Planning (CAPP), Computer Numerical Control (CNC), robotics, automated material handling, production planning, and manufacturing databases.
The CIM Wheel
The CIM wheel represents the integration of manufacturing functions around a central database. Product design informs process planning, which supports manufacturing. Production planning, inventory control, and quality control are interconnected, while management information systems provide business data.
2. Evolution, Need, and Benefits of CIM
CIM evolved from manual operations to NC machines, followed by CNC and DNC systems, and eventually the integration of CAD, CAM, and CAPP.
Need for CIM
Modern manufacturing requires high productivity, improved quality, reduced production time, and rapid response to customer requirements. Traditional siloed departments often cause data duplication and delays.
Benefits of CIM
- Reduced product development time
- Lower manufacturing costs
- Improved product quality
- Better resource utilization
- Increased flexibility
3. Concurrent Engineering (CE)
Concurrent Engineering (CE) is a systematic approach where life-cycle activities—design, manufacturing, assembly, testing, and disposal—are considered simultaneously.
Comparison: Sequential vs. Concurrent
In Sequential Engineering, activities occur one after another, often leading to late-stage design changes. In Concurrent Engineering, teams work in parallel, considering manufacturing requirements during the design stage.
4. Life-Cycle Integration in CE
The framework for integration in CE involves sharing information across market analysis, design, process planning, manufacturing, assembly, and maintenance. Key techniques include Design for Manufacturability (DFM), Design for Assembly (DFA), and Quality Function Deployment (QFD).
5. PLM, IPD, and Collaborative Development
Product Life Cycle Management (PLM) manages product information from concept to disposal. Integrated Product Development (IPD) aligns functional teams, while Collaborative Product Development uses digital tools to connect distributed teams. These systems reduce data redundancy and improve cross-functional cooperation.
6. Database Management Systems (DBMS)
A DBMS is software used to store, organize, and control manufacturing data. Its architecture includes three levels: external (user views), conceptual (logical structure), and internal (physical storage).
7. SQL in Manufacturing
Structured Query Language (SQL) manages relational databases. Data Definition Language (DDL) commands like CREATE and DROP define structures, while Data Manipulation Language (DML) commands like SELECT and UPDATE manage records.
8. Manufacturing Data and Databases
Manufacturing data includes product, process, production, quality, and resource data. Databases must ensure accuracy, consistency, security, and fast retrieval to support CIM integration.
9. Product Data Management (PDM)
PDM organizes and controls product-related information, such as CAD drawings and bills of materials. It provides version control, workflow management, and access control to ensure teams use the latest data.
10. Relationship Between DBMS and PDM
While a DBMS provides the infrastructure for data storage, PDM adds specialized functions like revision control and engineering change management. Together, they form the backbone of integrated product development.
11. Design for Manufacturability (DFM)
DFM ensures products are designed for easy and economical manufacturing. Principles include simplifying designs, reducing component counts, and standardizing parts to lower costs and improve quality.
12. Computer-Aided Process Planning (CAPP)
CAPP converts design information into manufacturing operations. Variant CAPP retrieves and modifies existing plans, while Generative CAPP automatically creates plans using decision logic and manufacturing rules.
13. Material Requirements Planning (MRP)
MRP determines material needs based on the Master Production Schedule (MPS), Bill of Materials (BOM), and inventory records. It ensures the right materials are available at the right time.
14. Cellular Manufacturing
Cellular Manufacturing groups machines into cells to process similar components. This reduces material handling and setup times. Techniques include Machine-Component Group Analysis and Similarity Coefficient-Based Methods.
15. Flexible Manufacturing Systems (FMS)
An FMS is an automated system of CNC machines and material-handling equipment. It offers high flexibility in routing, product variety, and volume, making it ideal for medium-volume production.
16. Computer Networks in CIM
Networks are classified by coverage: LAN (local), MAN (metropolitan), and WAN (wide). These networks enable the exchange of data between CAD systems, CNC machines, and enterprise servers.
17. OSI and TCP/IP Models
The OSI model provides a seven-layer framework for network communication. TCP/IP is the standard protocol suite, where TCP ensures reliable delivery and IP handles routing.
18. Network Interconnection Devices
Devices like repeaters, bridges, routers, and gateways connect network segments. They are essential for integrating heterogeneous manufacturing systems and ensuring efficient data flow.
19. Lean Manufacturing Principles
Lean Manufacturing focuses on maximizing customer value by eliminating waste. Key principles include identifying value, creating continuous flow, and implementing pull-based production.
20. Waste in Lean Production
Lean identifies seven wastes: overproduction, waiting, transportation, unnecessary processing, inventory, motion, and defects. Eliminating these improves flow and reduces costs.
21. Kaizen: Continuous Improvement
Kaizen involves small, frequent improvements by all employees. It uses the PDCA cycle (Plan, Do, Check, Act) to solve problems and standardize processes.
22. Agile and Web-Based Manufacturing
Agile Manufacturing emphasizes responsiveness to market changes. Web-Based Manufacturing uses internet technologies to enable remote collaboration and real-time information sharing across global supply chains.