An intelligent approach to design three-dimensional aircraft sheet metal part model for manufacture

Aircraft sheet metal part manufacturing is a knowledge-intensive process, and the manufacturability and manufacturing information are required to be considered in three-dimensional (3D) model by knowledge reuse. This paper presents a 3D model structure of the aircraft sheet metal part and an intelligent approach to design the model for manufacture combining intelligent manufacturability analysis with manufacturing information definition. Processability of part, formability of material and cost of fabrication are proposed to analyse the manufacturability of the part. Knowledge base for manufacturability analysis is established, and knowledge is reused to evaluate the part’s manufacturability intelligently to meet the constraints of manufacturing conditions. Non-geometric information is defined in the 3D model to meet the needs of digital manufacturing and inspection using model-based technology. An example is given to describe the process of design for manufacture, which shows that the approach can realize the concurrent design and digital manufacturing of aircraft sheet metal

The implementation of uncertainty evaluation model in manufacturability analysis system for miniature machine tool

The development of Manufacturability Analysis System for micro-machining domain (MicroMAS) is intended to address the need of the 4-axis Miniature Machine Tool (MMT) that require such system to assist the user in generating micro-component through manufacturability evaluation. One of the manufacturability aspects being assessed is the impacts from Uncertainty Evaluation Model (UEM) analysis that analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made MMT to be predicted and to further understand the origin of the errors on the machined micro-part. This paper reports on the implementation of UEM in the development of MicroMAS. Therefore, the results from uncertainty evaluation towards the MMT were integrated in the database which are interactively searched based on IF-THEN clauses in order to determine which rules satisfy the requirements expressed via inputs

A knowledge based expert system for moulded part design

In today's competitive market many consumer products are designed with complex curved shapes to meet customers' demands for styling and ergonomics. These styled products are commonly manufactured using moulding processes because they can produce a wide range of freeform shapes at relatively low cost. However, although injection moulding and metal casting allow a great deal of design freedom they also make significant demands on the designer to ensure that parts are designed with due regard for manufacturability. This paper describes a knowledge based moulding advisor that has been developed to provide design for moulding advice to designers during the design process. The main contributions of the research are the development of a hierarchical knowledge representation to allow moulding advice to be generated at different levels of detail and the integration of the expert system with a geometric part description extracted from a Computer Aided Design (CAD) solid model. A demonstrator for the manufacturing advisor has been implemented using the expert system shell CLIPS and integrated with CAD using feature recognition. The moulding advisor is able to generate tailored design for moulding advice for a range of manufacturing processes and materials and evaluate the manufacturability of a designed part at the feature level. The paper provides a case study for a simple moulded test part

A Student-Centered Learning Approach to Design for Manufacturability: Meeting the Needs of an Often- Forgotten Customer

A hands-on learning module was implemented at Marquette University in 2012 to teach biomedical engineering students about basic manufacturing processes, lean manufacturing principles, and design for manufacturability. It incorporates active and student-centered learning as part of in-class assembly line simulations. Since then, it has evolved from three class periods to five. The module begins with two classroom presentations on manufacturing operations and electronics design, assembly, and testing. Students then participate in an in-class assembly line simulation exercise where they build and test an actual product per written work instructions. They reflect on this experience and suggest design and process changes to improve the assembly line process and quality, save time, and reduce cost and waste. At the end of the module students implement their suggested design and process improvements and repeat the exercise to determine the impact of their improvements. They learn of the importance of Design for Manufacturability, well-written work instructions, process design, and designing a product not only for the end user, but also for the assemblers and inspectors. Details of the module, and its implementation and assessment are presented along with student feedback and faculty observations

A Hands-On, Active Learning Approach to Increasing Manufacturing Knowledge in Engineering Students

This paper describes a new learning module implemented as part of the senior capstone design course at Marquette University to teach engineering students about basic manufacturing processes, lean manufacturing principles, and design for manufacturability. The module includes several examples of active and student centered learning as part of an in-class assembly line simulation exercise. Students reflected on this experience, and suggested process improvements to save time, reduce cost and waste, and improve the assembly line process. They learned of the importance of manufacturing documentation, process design, and design for assembly. At the end of the module, students understood the importance of designing a product not only for the end user, but also for the assemblers and inspectors. Details of the module design and implementation will be presented along with comments from students

Under-the-cell routing to improve manufacturability

The progressive miniaturization of technology and the unequal scalability of the BEOL and FEOL layers aggravate the routing congestion problem and have a negative impact on manufacturability. Standard cells are designed in a way that they can be treated as black boxes during physical design. However, this abstraction often prevents an efficient use of its internal free resources. This paper proposes an effective approach for using internal routing resources without sacrificing modularity. By using cell generation tools for regular layouts, libraries are enriched with cell instances that have lateral pins and allow under-the-cell connections between adjacent cells, thus reducing pin count, via count and routing congestion. An approach to generate cells with regular layouts and lateral pins is proposed. Additionally, algorithms to maximize the impact of under-the-cell routing are presented. The proposed techniques are integrated in an industrial design flow. Experimental results show a significant reduction of design rule check violations with negligible impact on timing.Peer ReviewedPostprint (author's final draft

O-Band Subwavelength Grating Filters in a Monolithic Photonics Technology

The data communications industry has begun transitioning from electrical to optical interconnects in datacenters in order to overcome performance bottlenecks and meet consumer needs. To mitigate the costs associated with this change and achieve performance for 5G and beyond, it is crucial to explore advanced photonic devices that can enable high-bandwidth interconnects via wavelength-division multiplexing (WDM) in photonic integrated circuits. Subwavelength grating (SWG) filters have shown great promise for WDM applications. However, the small feature sizes necessary to implement these structures have prohibited them from penetrating into industrial applications. To explore the manufacturability and performance of SWG filters in an industrial setting, we fabricate and characterize O-band subwavelength grating filters using the monolithic photonics technology at GLOBALFOUNDRIES (GF). We demonstrate a low drop channel loss of -1.2 dB with a flat-top response, a high extinction ratio of -30 dB, a 3 dB channel width of 5 nm and single-source thermal tunability without shape distortion. This filter structure was designed using elements from the product design kit provided by GF and functions in a compact footprint of 0.002 mm2 with a minimum feature size of 150 nm.Comment: 4 pages, 3 figure