Appendix C
Current Engineering Design Tools

Tools for simulating manufacturing encompass various levels of CAD, CAM, CAE, PDM, and PLM tools. Solutions are usually tightly integrated vertically within the vendor's own environment, with different levels of "openness" within their architectures allowing integration or interoperability with other vendors' products. Some of the first-tier vendors for these types of product suites include the following:

  • EDS: Unigraphics/TeamCenter/I-deas/Vis-Mockup

  • Dassault Systemes: CATIA/ENOVIA/DELMIA

  • PTC: Pro-Engineer/Windchill/Product Vision

There are other vendors that also supply integrated solutions that do not encompass the full product life cycle. An example of one of these second-tier vendors is MSC Software, which provides an engineering analysis focused suite of products (including NASTRAN and PATRAN).

Many engineering tools for modeling and simulation of particular aspects of the performance of engineered devices and systems are in common use but are usually not well linked to other tools. These engineering design and analysis tools are grouped below by several of the categories shown in Figure 3-1. Each software tool is described briefly in terms of the design or analysis function it performs, and in some cases the underlying technology or technical assumptions.

ENGINEERING MODELING—SIMULATION AND VISUALIZATION

Multidisciplinary Optimization

Product (or vehicle) synthesis tools typically are used to explore a product's design space by bringing together multiple design and analysis disciplines (e.g., structural, electrical, performance) and trying to understand how a product will best meet the design requirements. The input used to support these synthesis tools typically comes from simplified physics models or from trend analyses sourced from detailed design and analysis tools. The earlier and better the design team understands the product's design space—including the interplay of variables, constraints, and requirements—the better the resulting product design will meet the customer's needs. The result is not only a product design but also analysis to show why one design is



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Retooling Manufacturing: Bridging Design, Materials, and Production Appendix C Current Engineering Design Tools Tools for simulating manufacturing encompass various levels of CAD, CAM, CAE, PDM, and PLM tools. Solutions are usually tightly integrated vertically within the vendor's own environment, with different levels of "openness" within their architectures allowing integration or interoperability with other vendors' products. Some of the first-tier vendors for these types of product suites include the following: EDS: Unigraphics/TeamCenter/I-deas/Vis-Mockup Dassault Systemes: CATIA/ENOVIA/DELMIA PTC: Pro-Engineer/Windchill/Product Vision There are other vendors that also supply integrated solutions that do not encompass the full product life cycle. An example of one of these second-tier vendors is MSC Software, which provides an engineering analysis focused suite of products (including NASTRAN and PATRAN). Many engineering tools for modeling and simulation of particular aspects of the performance of engineered devices and systems are in common use but are usually not well linked to other tools. These engineering design and analysis tools are grouped below by several of the categories shown in Figure 3-1. Each software tool is described briefly in terms of the design or analysis function it performs, and in some cases the underlying technology or technical assumptions. ENGINEERING MODELING—SIMULATION AND VISUALIZATION Multidisciplinary Optimization Product (or vehicle) synthesis tools typically are used to explore a product's design space by bringing together multiple design and analysis disciplines (e.g., structural, electrical, performance) and trying to understand how a product will best meet the design requirements. The input used to support these synthesis tools typically comes from simplified physics models or from trend analyses sourced from detailed design and analysis tools. The earlier and better the design team understands the product's design space—including the interplay of variables, constraints, and requirements—the better the resulting product design will meet the customer's needs. The result is not only a product design but also analysis to show why one design is

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Retooling Manufacturing: Bridging Design, Materials, and Production preferred over another and how the designs could be improved by changing variable limits, constraints, and requirements. COMPUTER-AIDED ENGINEERING Aerodynamics / Fluid Dynamics CFD (computational fluid dynamics) tools are generally used to evaluate the performance of a product in gas or fluid atmospheres (e.g., aircraft wing design). CFD provides an understanding of key fluid dynamic interactions with a three-dimensional description of flow. Various methodologies are available, including partial Navier-Stokes, full Navier-Stokes, and hybrid approaches. Panel methods solve a linear partial differential equation numerically by approximating the configuration surface by a set of panels. Various methodologies are available to the analyst. Propulsion CFD (computational fluid dynamics) tools—see "Aerodynamics / Fluid Dynamics" section. Thermal Modeling Aeroheating analysis tools are typically used to define the thermal environments that a product's structure will be exposed to and in which it must perform its function. Various technologies are employed, including finite difference, finite element, and CFD. EMP (electromagnetic pulse) / lightning strike analysis tools are used to assess the survivability of a product to these phenomena—whether natural or human-induced. Environmental analysis tools are used to describe the environments to which a product is subjected, including temperature, pressure, humidity, and others. Reentry analysis tools are used to analyze the aerothermal environments specific to vehicle reentry. TPS (thermal protection system) analysis tools are used to design and analyze the performance of the systems that are used to protect or insulate a product from the thermal environments to which it is exposed. Structural Analysis Ballistics damage tools are used to assess the effect of load path loss on dynamic response and aeroelastic margins. Local damage can be predicted with high-fidelity nonlinear finite element tools. The overall changes to dynamic response and aeroelastic margins are then evaluated relative to their effect on aircraft performance. Damage tolerance tools are used to predict residual strength in the presence of flaws and the remaining service life given crack growth arising from such flaws. The flaws could be inherent material discontinuities or a result of fatigue, corrosion, or accidental damage. Various methods

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Retooling Manufacturing: Bridging Design, Materials, and Production are used to calculate the stress intensity and crack growth retardation and acceleration. Durability analysis tools are used to predict the economic life of a structure based on the expected usage, material, and stress concentrations. Local stress and strain excursions are calculated using a variety of methods, and life predictions are based on stress-displacement curves. Fatigue analysis tools (see Durability analysis tools) FEA (finite element analysis) tools use numerical methods to idealize a structure and then solve for the displacements and internal loads due to a general loading condition. The types of analysis can vary from simple linear-static to complex nonlinear geometry and material. FEM (finite element modeling) tools typically have a graphical user interface (GUI) to rapidly create the finite element models for the finite element analysis (FEA) code of choice. The FEM tool, typically with a GUI, is then used to process the FEA results. Fracture mechanics analysis tools (see Damage tolerance tools) Subsystems Design and Analysis Environmental control design and analysis tools are used to define onboard environmental control systems and simulate their performance. This covers the total design process from a logical, functional, and physical viewpoint. Examples include onboard oxygen generation systems. Fluid flow design and analysis tools are used to design and analyze fluid systems for platforms. Included in these analyses are fault generation and failure scenarios. Fuels design and analysis tools are used to define onboard fuel systems and simulate their performance. This covers the total design process from a logical, functional, and physical viewpoint. Hydraulic systems design and analysis tools are used to define onboard hydraulic systems and simulate their performance. This covers the total design process from a logical, functional, and physical viewpoint. ELECTRONIC DESIGN AUTOMATION Electrical System Design / Analysis Circuit design tools provide the layout design for circuit boards and electronics. E/CAD (electrical and electronics computer-aided design) tools are utilized to perform circuit design, systems and wiring design, and analysis. Electrical installations design tools orient the electrical components (equipment and wiring) in three-dimensional (3D) geometric space. Deliverables generally include installation drawings, manufacturing plans for equipment and wiring, support provisions, protection mechanisms, and support structure. Generally, this environment is utilized to integrate the systems and wiring

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Retooling Manufacturing: Bridging Design, Materials, and Production requirements (functional and logical requirements) with the physical requirements (3D structure and manufacturing and supportability requirements). EMI (electromagnetic interference) analysis tools evaluate an electrical system to determine if any electromagnetic disturbance, phenomenon, signal, or emission could cause undesired response, malfunction, degradation, or performance of electrical and electronic equipment. Analysis tools utilize information from the 3D physical design or the circuit board layout and the signal requirements / systems operation to conduct the analysis / modeling activities. Logical design and analysis tools are typically employed after the definition of the level-three wiring schematic. The pin-to-pin signal requirements between the components in a system are finalized via inputs from analysis activities such as wiring length requirements received from the physical 3D CAD tools and electrical load analysis tools (which assist in finalizing the wiring gage required) and an analysis of electromagnetic compatibility/interference, which assists the designer in the grouping of compatible signals into wire bundles/harnesses and the definition of separation requirements for dissimilar and incompatible signals. Wiring schematic design and analysis tools are used to generate the design and analyze the performance of schematic diagrams. Schematic diagrams are utilized to describe the functionality of a system. A level-one schematic describes the top-level systems-to-system interactions. A level-two schematic is a block diagram for component- and function-level interactions. A level-three schematic, sometimes called a wiring schematic, is a detailed view of all equipment, connectors, wiring, and pins. During the design process, feedback from the logical design and manufacturing analysis process results in an update of the level-three schematic to include production disconnects or inline connectors that facilitate the manufacturing process. COMPUTER-AIDED GEOMETRIC DESIGN Mechanical Design and Analysis Kinematics and dynamics tools are used to analyze or simulate mechanical systems in motion based on the Newtonian physics of rigid bodies. M/CAD (mechanical computer-aided design) tools are typically used to generate the three-dimensional geometric representations of products and their constituent component parts and pieces. These geometric representations are often the starting point for other engineering design and analysis tools. Technologies that are often applied to these CAD systems include Boolean process, 3D wire-frame processes, 3D surfaced representations, 3D solid models, parametric design processes, relational design processes, and knowledge-driven (or intelligent) design processes. Manufacturing Modeling—Simulation and Visualization 3D factory definition and analysis (factory analysis and simulation) consists of modeling the physical layout and the assembly of defined processes in an existing, new, or reconfigured facility. This process is used to analyze and validate work flow, space requirements, tooling concepts, methods of part and assembly movement, staging requirements, and supplier flow, and to identify resource requirements. This process is also used to validate new lean initiatives prior to incorporation. Product teams use this process to determine factory design viability and

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Retooling Manufacturing: Bridging Design, Materials, and Production to explore and validate new facility concepts. 3D PFA (process flow analysis, or discrete event analysis and simulation and fabrication and assembly flow) is the process of determining the performance of the build plan, given a limited set of resources. This analysis helps to determine the resource levels and cycle times needed to produce a given configuration of a product. PFA can be performed on an individual control station or groups of control stations within the build plan for a single cycle or several years. PFA is one of many enablers that allow us to predict cost and cycle times without having to produce a single unit. Assembly analyses describe, visualize, analyze, and communicate the proposed build process as it matures during a program. Assembly simulations are created using an iterative process that enables them to be concurrently developed as the product, process, and resources mature. Simulation provides a three-dimensional graphical visualization of the assembly process that includes engineering parts, design tools, hand tools, human models, and other resources. Assembly simulations are used to perform analysis of engineering data to determine interference checks and assembly variations to create an efficient repeatable process. Casting and molding analysis consists of modeling and simulation of the flow of molten materials into molds, as well as the thermal aspects of cooling and solidification. Machining and forming analysis consists of modeling of material removal by cutting operations and forming of metals by forging and sheet-metal forming. PROCESS PLANNING Classes of engineering design and analysis tools are grouped by discipline, skill, or function: Avionics design / analysis Guidance, navigation, and control design and analysis Mass properties analysis Affordability and cost-estimating analysis Physics-based performance models