Research and design of an embedded controller and GUI for the automation of the armature Volt-Drop test.

Abstract

In a rapidly evolving technological and industrialised society, automation is a current and growing trend. The concept is typically applied to uneconomical processes and extends from the automation of highly complex processes to those that are less complex. This dissertation discusses the automation of a previously mundane, manual, time-consuming and inefficient task using an embedded controller with dual enhanced microcontrollers as its core. Spoornet recognised the need to automate this and other processes hence a drive was initiated by Spoornet’s Engineering and Technology department into the study of automation principles and techniques that can be used as a basis for the automation of workshops and test centers. This research stems from the above mentioned drive. The Volt-Drop Test was the process that was used as a model to investigate the considerations, boundaries, design concepts and the hardware and software development that is inherent in the automation of a process. The design of the controller that facilitates the automation of the Volt-Drop Test was completed after research into embedded systems, embedded microcontrollers, programming languages and techniques, digital electronics, analogue electronics, digital system design concepts and techniques, analogue system design concepts and techniques, and the latest available electronic components. A Graphic User Interface (GUI) was developed to interface with the controller to set up test parameters, display the present test status, perform calculations on the data received from the controller and display faults in the armature under test. Further, the GUI has the functionality to save all test data in a predefined and secure location to be retrieved and viewed as historical data or used for trending. A Remote Graphic User Interface (RGUI) was also developed. This interface is used solely to view test data (retrieved from the saved history files), from any geographic location provided that the user has been granted access to the secure location in which this data is saved.

In the testing phase, all tests were carried out using high quality, high accuracy and recently calibrated instrumentation. The test results obtained largely reflected what was expected from the system when compared to simulations that were carried out on the controller and the GUI during their development. With regard to the automation process, the system follows the procedure as it was designed with respect to correct switching sequences, response to system errors, timing of events and correct and efficient communication between the controller and the GUI. In terms of the data acquisition aspects the system captures, converts, calculates, analyses and logs data, within the expected input range with a level of accuracy that is considered to be high (a maximum percentage error of 0.75% - expressed as a percentage of the injected test supply) for this type of application when compared to the accuracy of present test methods.