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Full-Text Articles in Aerospace Engineering
Hierarchical Optimal Force-Position-Contour Control Of Machining Processes. Part I. Controller Methodology, Yan Tang, Robert G. Landers, S. N. Balakrishnan
Hierarchical Optimal Force-Position-Contour Control Of Machining Processes. Part I. Controller Methodology, Yan Tang, Robert G. Landers, S. N. Balakrishnan
Mechanical and Aerospace Engineering Faculty Research & Creative Works
There has been a tremendous amount of research in machine tool servomechanism control, contour control, and machining force control; however, to date these technologies have not been tightly integrated. This paper develops a hierarchical optimal control methodology for the simultaneous regulation of servomechanism positions, contour error, and machining forces. The contour error and machining force process reside in the top level of the hierarchy where the goals are to 1) drive the contour error to zero to maximize quality and 2) maintain a constant cutting force to maximize productivity. These goals are systematically propagated to the bottom level, via aggregation …
Hierarchical Optimal Force-Position-Contour Control Of Machining Processes. Part Ii. Illustrative Example, Yan Tang, Robert G. Landers, S. N. Balakrishnan
Hierarchical Optimal Force-Position-Contour Control Of Machining Processes. Part Ii. Illustrative Example, Yan Tang, Robert G. Landers, S. N. Balakrishnan
Mechanical and Aerospace Engineering Faculty Research & Creative Works
There has been a tremendous amount of research in machine tool servomechanism control, contour control, and machining force control; however, to date these technologies have not been tightly integrated. This paper develops a hierarchical optimal control methodology for the simultaneous regulation of servomechanism positions, contour error, and machining forces. The contour error and machining force process reside in the top level of the hierarchy where the goals are to 1) drive the contour error to zero to maximize quality and 2) maintain a constant cutting force to maximize productivity. These goals are systematically propagated to the bottom level, via aggregation …
Output Feedback Force Control For A Parallel Turning Operation, Raghusimha Sudhakara, Robert G. Landers
Output Feedback Force Control For A Parallel Turning Operation, Raghusimha Sudhakara, Robert G. Landers
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Parallel machine tools (i.e., machine tools capable of cutting a part with multiple tools simultaneously but independently) are being utilized more and more to increase operation productivity, decrease setups, and reduce floor space. Process control is the utilization of real-time process sensor information to automatically adjust process parameters (e.g., feed, spindle speed) to increase operation productivity and quality. To date, however, these two technologies have not been combined. This paper describes the design of an output feedback controller for a parallel turning operation that accounts for the inherent nonlinearities in the force process. An analysis of the process equilibriums explains …
Lifecycle Analysis For Environmentally Conscious Solid Freeform Manufacturing, Yanchun Luo, Ji Zhiming, Ming-Chuan Leu, R. J. Caudill
Lifecycle Analysis For Environmentally Conscious Solid Freeform Manufacturing, Yanchun Luo, Ji Zhiming, Ming-Chuan Leu, R. J. Caudill
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A lifecycle based process model for analyzing the environmental performance of SFM processes and SFM based rapid tooling processes is presented in this paper. The process environmental performance assessment model considers material, energy and disposal scenarios. The material use, process parameters (e.g. scanning speed) and power use can affect the environmental consequence of a process when material resource, energy, human health and environmental damage are taken into account. The presented method is applied to the SLA process and two SLA based rapid tooling processes. The method can be used to compare different rapid prototyping (RP) and RT processes in terms …