## 3 Research and Development Methodology  
Models--WPF Applications with the Model-View-ViewModel (MVVM) Design Pattern for CNC Machine Interface  
Creating a CNC machine operator interface with Windows Presentation Foundation (WPF) [38] utilizing the Model-View-ViewModel (MVVM) design pattern offers a structured, scalable, and maintainable solution for desktop applications. WPF, as a UI framework designed for developing visually appealing desktop applications, when paired with the MVVM pattern, facilitates a clear separation between the user interface (View), business logic (Model), and data binding logic (ViewModel). This makes it a favored choice for industrial applications, including CNC machine monitoring. In the context of a CNC machine operator interface, MVVM and WPF provide a flexible and powerful platform for real-time monitoring, control, and diagnostics. * Real-Time Monitoring: The application can monitor critical CNC parameters such as spindle speed, feed rate, tool wear, and temperature. Using data binding, the View-Model updates the UI in real-time with the latest sensor data from the CNC machine. Example: a graph displaying spindle speed over time can be dynamically updated by binding the graph's data source to a collection in the ViewModel, which receives live updates from the machine's sensors. * Machine Control: The interface allows operators to control the CNC machine remotely. Buttons in the UI can be bound to commands in the ViewModel, enabling operations such as starting, pausing, or stopping the machine. The ViewModel would then translate these commands into machine-specific API calls or instructions. Example: a \"Start\" button would be bound to a StartMachineCommand in the ViewModel, which communicates with the machine's control system to initiate machining. * Data Visualization: Using WPF's data visualization libraries (like OxyPlot or LiveCharts), operators can view graphs, tool paths, and other CNC performance data. These can be customized to show historical trends or real-time machine data, providing insights into the CNC process. Example: a real-time plotting graph that displays tool wear progression during machining, enabling the operator to predict when maintenance is required. * Fault Detection and Alerts: The MVVM pattern allows for the seamless display of alerts and notifications when the machine encounters errors or operational anomalies. The Model layer would handle the logic for detecting faults, while the ViewModel would notify the View to display alerts. Example: when the CNC machine detects a tool failure, the ViewModel can trigger an alert in the UI, highlighting the issue and providing options for operator action. * Historical Data and Reporting: Operators can access historical machine data, such as previous jobs, tool paths, and machine performance, using the WPF interface. This allows operators to review past performance and adjust parameters for optimal efficiency. Example: an operator could pull up a report of machine performance over the last 24 h, presented as a set of graphs showing key metrics like spindle speed and tool wear. * CNC Machine Connectivity: The ViewModel acts as the mediator between the UI and the CNC machine's control system (e.g., via an API or communication protocol like OPC UA). This enables the application to send instructions to the machine and receive updates on its operational status. Example: using the CNC machine's API, the ViewModel can send toolpath data to the machine and receive feedback on the operation's progress. Key Components of a CNC Interface:  
* Data Binding: WPF's powerful data binding feature allows for real-time updates in the UI whenever the underlying data (Model) change. For a CNC machine, this couldinclude real-time updates of the machine's status (e.g., temperature, spindle speed, tool wear). * Commands: In MVVM, user interactions (e.g., button clicks) are handled through commands in the ViewModel, which executes business logic in the Model.