7.14 - CAM
Computer-aided manufacturing (CAM) is the use of computer software to control machine tools and related machinery to manufacture parts and components. CAM may also refer to the use of computers to assist in all operations of a manufacturing plant, including planning, management, transportation and storage. Its primary purpose is to create a more responsive production process with appropriate tooling to produce components with more precise dimensions and material consistency, using only the required amount of raw material (thus minimizing waste), while simultaneously reducing energy consumption.
CAM is a downstream process after computer-aided design (CAD) and sometimes computer-aided engineering (CAE). The model generated in CAD and validated in CAE can be input into CAM software, which then controls the machine tools for its manufacture.
Businesses are most effective and competitive when based upon natural groups in the office and in manufacturing. This will enable simple and integrated locally owned computer applications and associated databases to be designed, operated and maintained with significant productivity gains and competitive advantage.
Computer Aided Manufacture (CAM), in the sense of stand alone programming tasks and machine process control units has previously been employed often with little productivity benefit to the total business.
Design of flexible manufacturing systems in the form of cells based on natural groups with ownership of quality, materials handling and storage, together with appropriate planning and control systems (such as JIT/MRP), have eliminated non-value added activity associated with complex functional arrangements. These cells also focus those areas where CAM be used effectively to enhance the methodology already applied and also allow a total systems approach to their justification.
The be fully effective such stand alone applications must be capable of integration with design (CAD), process planning (CAPP) and JIT/MRP production management (CAPM) in an integrated environment as shown in the diagram below.
CAM – Effective integrated structure and systems solutions are now being achieved in many manufacturing businesses.
Today the market demands rapid response and high variety. This means that cells have to be designed for high flexibility, combining the necessary facilities to manufacture complete products to meet customer requirements in a cost effective way while handling the required product mix just in time.
The areas in which CAM can support this are process are specifically:-
- Machining – through direct feed of product data and the associated process control information.
- Maintenance – including expert system support for diagnostic output for quality (e.g. SPC support)
This is summarised in the following diagram:-
The operation and maintenance of such systems is clearly simplified through the application of a control systems strategy that includes rationalisation of controllers, distributed intelligence (particularly in the form of simple programmable logic controllers PLC’s) and carefully design levels of control with defined interfaces, to allow a phased approach to their design and implementation. This requires careful choice of:-
- Generic standards for hardware interfacing
- Generic standards for networks
- Generic standards for software interfacing
- The use of international standards for machine and communications control
Remember the need to integrate system architecture by input / output analysis across the levels – business control, production control, process control and material flow control.