Date of Award
Electrical and Computer Engineering
CC BY-NC-ND 4.0
Programmable Logic Controllers (PLCs), traditionally used for process control and automation, have certain limitations. Firstly, they operate by running the ladder logic in a scan cycle that has three steps: inputs scanning, program execution, outputs updating. This sequential execution affects the response time of the PLC for critical events, as they will keep waiting until they are read in an inputs scanning step. Secondly, PLCs are expensive, available only in standard configurations and need to be mounted on special panels. Finally, using PLC adds to wiring complexity of the system and reduces scalability. As a solution to these limitations, this thesis proposes using an MCU based embedded control system with event driven software architecture. For the implementation, an ATMEGA-2560 MCU is selected and used in X-Ray measurement system automation board. The controller is designed and implemented for Proto Manufacturing iXRD stress measurement system to replace the existing PLC-based system. All iXRD machine inputs are configured to generate interrupts at Atmega microcontroller to ensure faster response times based on the priority of the system events. The hardware and the firmware designs implemented in the thesis allow quick and easy expansion of the system by adding new inputs or outputs with a minimal wiring and smaller number of new components. The new design minimizes the system number of components, integration time and complexity, thereby reducing the overall system setup and maintenance costs.
Wehbe, Hussein, "Reducing Complexity Increasing Scalability on X-Ray stress system" (2017). Electronic Theses and Dissertations. 5956.