OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Computing and Software The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. OBJECTIVE: The objective of this topic is to develop and demonstrate an innovative digital geometry and analysis framework to support holistic aerospace system synthesis in conceptual and preliminary multidisciplinary design. A key element of such a framework is a parametric, attributable, design-oriented geometry system with a flexible application programming interface (API). The API allows the mathematical geometry description and prescribed model attributes to be richly and bidirectionally connected to a wide variety of multidisciplinary, multi-fidelity engineering tools that require different representations of the same design configuration. Currently, different design disciplines must manually produce their own analysis geometry from a disconnected, non-attributed computer-aided design (CAD) model. The objective unified system represents a significant step beyond the current state-of-the-art industry aerospace processes and will result in a multiple order-of-magnitude increase in the number of design alternatives (within the same timeframe and cost) that can be evaluated with multidisciplinary physics-based modeling and simulation during early aerospace system design exploration. DESCRIPTION: A new era of digital engineering offers unprecedented opportunities to leverage computational modeling and simulation, vehicle-level multidisciplinary-design optimization (MDO), and operations analysis to identify aerospace system concepts with maximum performance and military utility. To achieve high confidence in performance and effectiveness predictions for novel system configurations in early conceptual/preliminary design stages, it is desirable to integrate multi-fidelity, physics-based analysis tools from the many engineering design disciplines that traditionally contribute to an aircraft integrated product team (IPT). These include design disciplines such as aerodynamics, structures, flight dynamics, propulsion, power and thermal management, payload/subsystem integration, and manufacturing. A significant barrier to achieving a streamlined, multidisciplinary digital integration is the disconnect between a primary/central geometry or CAD model and the geometric needs of different engineering disciplines. In practice, disciplinary analysts reference the central geometry to manually create one or more new geometry models and attribute them based on the needs of their discipline's analysis and design tools at different fidelity levels. This effectively leads to the production of the same number of geometry models as there are participating design disciplines, which is time consuming and labor intensive. Further, when the central geometry is parameterized to support MDO and automated conceptual design exploration, it is challenging to parameterize each individual disciplinary representation, automatically attribute them, and maintain consistent design intent. To overcome these challenges the framework in this effort shall include a parametric, attributable, design-oriented geometry system with a flexible application programming interface (API). The API must expose the mathematical geometry description and prescribed model attributes to enable bidirectional data transfer to/from multidisciplinary, multi-fidelity engineering tools. This facilitates the direct connection of engineering tools to the primary design parameterization and attribution, which enables more efficient automation of disciplinary geometry generation. To represent complex aerospace system configurations of real-world interest and support anticipated MDO-based design workflows, the underlying geometry system must have several key capabilities and fundamental features: Ability to handle all types of air vehicle and aerospace system geometry including water-tight outer mold line (OML), non-manifold inner mold line (IML), and internal subsystem/component geometry simultaneously and independently. Capable of representing geometric objects of all dimensional levels: 0D, 1D, 2D, 3D, and combinations thereof. Support both bottoms up (e.g., sketch curve and extrude) and top down (Boolean operations on primitives) construction of arbitrarily complex geometric models. Differentiated (analytically to the extent possible) such that the sensitivities of the geometry can be computed with respect to prescribed parametric design variables. Attribution system wherein arbitrary descriptive model attributes are assignable to the geometry as it is procedurally constructed. Scriptable geometry definition and attribution using well documented, flexible scripting language. Application programming interface (API) exposure of both mathematical geometry representation and model attribution. Beyond the fundamental attributes above, there are a number of advanced geometry system and analysis/design framework capabilities that are of interest in this development effort: Ability to generate many different variations of parametric, attributed, geometry consistent with the needs of different disciplines or analysis fidelity-levels from a single model definition containing design variable parameterization, attributes, and design intent. High-quality, robust body/surface intersections with user-specified continuity and dimensional extent of transition surfaces. Multi-fidelity design variable parameterization or hierarchical/linked global/local design variables to support cases where increasing analysis fidelity level requires enriched design parameterization with more variables for meaningful optimization. Strategies should address bidirectional traversal of parameterization hierarchy (low-to-high and high-to-low). Unsteady/transient geometry definition to support specified shape or configuration changes over time (morphing, articulation, store release, etc.). This includes computing the sensitivity of the geometry shape with respect to the unsteady/time parameters. Utilities for automated internal airframe packaging, modification of bodies with internal geometry, and layout of internal subsystems/geometry with constraints (e.g., location/proximity, center-of-gravity, volumetric fit). Packaging strategies should consider interaction with disciplinary physics (e.g., aerodynamics, structures, etc.) in addition to purely geometric considerations. PHASE I: To demonstrate that the technology is ready for a D2P2, the applicant(s) should substantiate that their basic geometry system possesses the majority of the key capabilities and fundamental features highlighted in the topic description including: (i) generating simultaneous water-tight outer mold line (OML), non-manifold inner mold line (IML), and internal subsystem/component geometry, (ii) representing objects of all dimension levels (0D, 1D, 2D, 3D, and combinations thereof), (iii) demonstration of differentiated geometry, (iv) scriptable geometry definition and attribution, and (v) API exposure of both mathematical geometry representation and model attribution. In addition, proposers should clearly identify potential technical limitations and areas that require additional development to achieve these basic capabilities. The emphasis of the D2P2 effort should be implementing advanced features of the geometry system and new framework capabilities identified in the topic description. Finally, proposers should illustrate any prior use of their geometry system within an automated or multidisciplinary design exploration process and highlight the degree of coupling and API features. PHASE II: Phase II will develop and deliver a mature prototype framework implementing the advanced capabilities and features described above and demonstrate its usage in multiple air vehicle analysis and design workflows on relevant applications of Air Force interest. A sustainable ecosystem for software documentation and ongoing maintenance should be considered part of a mature prototype. The prototype demonstrations should represent workflows and processes that are characteristic of early conceptual/preliminary design such as aerospace system multidisciplinary design optimization (MDO) studies, multi-fidelity analyses, parametric sweeps to evaluate performance, or others. The Air Force will work with successful offerors to define relevant applications at a sufficient complexity level; however, proposals should clearly communicate which capability/feature of the framework will be demonstrated by different cases. Due to the potential distribution limits on relevant applications, the offerors must be able to accommodate processing, communication, and storage of Controlled Unclassified Information (CUI) and Controlled Technical Information (CTI). PHASE III DUAL USE APPLICATIONS: The proposed technology is applicable to a wide variety of customers throughout the Department of Defense (DoD) and other government agencies (NASA, DOE, etc.). It is also a pervasive need throughout many engineering industries (aerospace/defense, automotive, marine, consumer products, etc.) that are employing simulation-driven, multidisciplinary computational design processes, and digital engineering to accelerated product development, which offers many dual-use commercialization opportunities. Within AFRL, future efforts utilizing core project/program funding (non-SBIR) will be considered to expand the framework technologies to additional application areas. REFERENCES: 1. Bryson, Dean, Haimes, Robert, and Dannenhoffer, John, Toward the Realization of a Highly Integrated, Multidisciplinary, Multifidelity Design Environment, AIAA SciTech 2019, 2019. 2. Haimes, Robert, and Dannenhoffer, John, The engineering sketch pad: A solid-modeling, feature-based, web-enabled system for building parametric geometry, 21st AIAA Computational Fluid Dynamics Conference, 2013. 3. Dannenhoffer, John, and Haimes, Robert, Generation of Multi-fidelity, Multi-discipline Air Vehicle Models with the Engineering Sketch Pad, 54th AIAA Aerospace Sciences Meeting, 2016. 4. Dannenhoffer, John, and Haimes, Robert, Design sensitivity calculations directly on CAD-based geometry, 53rd AIAA Aerospace Sciences Meeting, 2015. 5. McDonald, Robert A., and Gloudemans, James R., Open vehicle sketch pad: An open source parametric geometry and analysis tool for conceptual aircraft design, AIAA SciTech 2022, 2022. 6. Camba, Jorge D., Contero, Manuel, and Company, Pedro, Parametric CAD modeling: An analysis of strategies for design reusability, Computer-Aided Design 74 (2016): 18-31. 7. Riesenfeld, Richard F., Haimes, Robert , and Cohen, Elaine, Initiating a CAD renaissance: Multidisciplinary analysis driven design: Framework for a new generation of advanced computational design, engineering and manufacturing environments, Computer Methods in Applied Mechanics and Engineering 284 (2015): 1054-1072. 8. Robinson, Trevor T., et al., Optimizing parameterized CAD geometries using sensitivities based on adjoint functions, Computer-Aided Design and Applications 9.3 (2012): 253-268. KEYWORDS: geometry; air vehicle design; multidisciplinary design optimization; MDO; CAD; simulation; computational; simulation; conceptual design
