Theme III: Process Planning and Validation Theme Objective: To develop advanced geometric computing algorithms and novel closed-loop machining platforms to generate and validate process plans for producing quality machined parts. Sub-Themes: IIIA. Cutter-Part Engagement Geometry Determination IIIB. On-line Process Re-planning IIIC. Off-line Process/Part Validation

Theme IV Modular Machine Tool Controls & Sensors Theme II Machine Tool Error Models Role of Theme III in Overall Network IIIA Cutter-Part Engagement Geometry Determination IIIC Off-line Process/Part Validation Theme V Virtual Machining System Process Plan Machined Part IIIB On-line Process Re-planning Theme I Materials & Machining Models

Theme III Projects Theme Researchers: H.Y. Feng (UBC), P.H. Gu (Calgary), A.D. Spence (McMaster) Collaborating Network Researchers: Y. Altintas (UBC), P. Koshy (McMaster) Academic Collaborators: R. Fleisig (McMaster), D.Y. Xue (Calgary) Industrial Collaborators: F.-É. Delorme, S. Engin (Pratt & Whitney Canada), M. Desnoyer (Origin International), D. McPhail (Memex Automation) Four Master’s and four Ph.D. students

IIIA.1: Analytical Formulation of Cutter-Part Engagement from Z-Buffer Images Benefits: closed-form solutions  accuracy & efficiency Proposed Methodology: – Identify the boundary points – Reconstruct the desired piecewise smooth analytical curve Current Progress: one MASc to start in September 2011

IIIA.2: Rough / Semi-Finish Machining Optimization The originally proposed B-rep (boundary representation) scheme – not robust enough. Mesh-based scheme is being explored.

IIIB.1: CNC and Inspection Hardware Integration To develop integrated inspection and GD&T decision making at the CNC machine tool GD&T processing with Origin software converted to embedded system Integration and feedback using Memex CNC control interface

IIIB.2: Modeling and Robust Localization of Free- Form Surfaces To develop new modeling techniques & localization methods for precision inspection of free-form surfaces. Main feature: considering both the reconstructed curve/surface and its uncertainty at different locations.

IIIB.3: Measurement Compensated Finish Machining To use inspection data to optimize heat treated / cast part finish machining tool paths. Tool path generation for compressor blade fillet.

IIIB.4: Surface Comparison and Tool Path Re- planning To determine the geometric errors, analyze the errors and develop compensation methods for tool path re-planning. – Determine magnitude and distribution of errors. – Re-program the tool paths to compensate the errors.

IIIC.3: Comprehensive Geometric Error Evaluation of Complex-Shaped Parts To fully automate the geometric error evaluation task of complex-shaped machined parts such as compressor, impeller, or turbine blades.

IIIC.4: Section-Specific Geometric Error Evaluation via Surface Scanning To enable accurate evaluation of geometric errors at specific sections of the machined free-form parts from complete surface scans. Current work: scanned noise reduction