UBC Theses and Dissertations
Integration of manufacturing process control and optimization with a general purpose multi-processor controller Ardekani, Ramin
The objective of this thesis is to demonstrate the importance of control software and hardware design in economic optimization of a production process. It is proposed that the improvement in production economics depends on the system's ability to meet the needs of a process model formulated from a sound understanding of the process. To illustrate these concepts, an NC lathe machining language is created to exploit the UBC Controller's ability for reducing production cost, ensuring part quality and improving machining safety, all based on the guidelines from a practical process model. The language uses a feature based approach to part geometry definition which simplifies data entry and operation planning. The tool path is automatically generated for volume primitives and sent to the controller with process control information. Unlike other systems, which are restricted by the traditional NC code block format in communicating process information to the controller, the process data can be made to correspond with small motion increments and help the controller cope with the expected variations in cutting conditions due to the cut geometry. Experiments with a force monitoring scheme demonstrate how a simple algorithm can keep the force within the prescribed limits for machining safety and product quality. Implementation of a rudimentary process identification and optimization scheme shows the system's ability to reduce machining cost while observing the practical constraints. This low cost system is intended to allow smaller firms to benefit from the current level of process knowledge and production technology.
Item Citations and Data