Historically, the primary role of simulation has been in optimization and validation—things that tend to be done late in the product development process. It’s been generally recognized, for quite a long time, that there is real value to be gained in moving simulation up earlier in the process, to the detail design phase. Many commerical simulation software vendors now offer products designed just for this purpose. But, the success of those products suggests a question: Is there value in moving simulation up even further?
Three very differerent projects attempt to answer that question. The European CRESCENDO project, the DARPA Adaptive Vehicle Make program, and Dassault Systèmes Working Model are each ambitious attempts to tame the increasing complexity of aerospace and defense programs. And each relies heavily upon moving simulation up in the process. All the way up.
The European Commission’s CRESCENDO project includes a consortium of aeronautic manufacturers, research centers, universities, and software/solution/service companies. 59 partners from 13 different countries are participating.
The stated ambition of the consortium is “to make a step change in the way that modeling and simulation activities are carried out, by multi-disciplinary teams working as part of a collaborative enterprise, in order to develop new aeronautical products in a more cost and time efficient manner.”
It’s a big ambition. The path they’re taking to get there is through the development of what is referred to as the Behavioral Digital Aircraft (BDA). The BDA is what you think it is: a massively large functional model of the entire aircraft, created early, and refined throughout the development process.
The BDA consists of two parts: The BDA Dataset is a federated multipartner, multilevel, multidiscipline, multiquality behavioral digital representation of an Aircraft and all its constituent systems and subsystems. It includes both models and simulation data. BDA Platforms, of which there are many instances, implement collaborative and multiphysics simulation capabilities to manage, manipulate, preserve, reuse and enrich the BDA Dataset.
The BDA architecture is based on open standards, such as BPMN (Business Process Model and Notation), UML, SysML, STEP AP233 Systems Engineering, and STEP AP239 Product Life Cycle Support, among others.
While the initial BDA implementation focuses on a handful of use cases, it can ultimately grow to comprise all of the modeling and simulation capabilities and services required to represent all of the behavioral, functional and operational aspects of an aircraft and its constituent systems. It’s not about just modeling and simulating parts; it’s about simulating the complete aircraft and its overall behavior.
Adaptive Vehicle Make
The Defense Advanced Research Projects Agency (DARPA) Adaptive Vehicle Make (AVM) is a portfolio of programs aimed at developing a new approach to design, verification, and manufacturing of complex defense systems and vehicles.
The status quo approach, based on the MIL-STD-499A (1969) systems engineering process, is to decompose the system based on arbitrary cleavage lines, then have separate teams work on building and optimizing each subsystem for size, weight, and performance. Once all the subsystems are sufficiently mature, they are integrated into a complete system. The system is then tested against requirements. As a rule, multiple fix/retest iterations are required, until the system meets its requirements, or the DoD gets tired of shoveling money into the project.
META, a program under AVM, has the goal of developing a framework and tool chain supporting model-based design optimization and verification, usable early in the design process.
DARPA’s big goal is to apply the META framework and toolchain to design, manufacture, integrate, and verify a complex aerospace system 5X faster than with a conventional design/build/test approach. Whether that goal is achievable may be shown soon, in the DARPA FANG design challenge.
FANG (Fast, Adaptable, Next-Generation Ground Vehicle) is competition, to design an amphibious personnel carrier using the META tools. It is open to U.S. individuals and companies, and is being hosted on the www.vehicleforge.org site, which was developed as part of the META program.
As part of the design challenge, DARPA is providing a component model library. Each component model includes a CAD-based representation (in STEP and PTC Creo format), a multi-domain physics model representing component behavior, inputs, outputs, and limitations (in the Modelica language), component instance data (in XML), and reference data with notes on data sources. Competitors can also create their own component models, to extend this library.
DARPA is providing two different META tool chains, which competitors may use at no cost. The first, called CyPhy, was developed by Vanderbilt University in collaboration with MIT, PARC, SRI, and several other partners, in a free, open-source implementation. The second, called CyDesign Studio, was developed by CyDesign Labs, Silicon Valley startup founded to commercialize earlier R&D efforts on the META program.
CyDesign may be representative of the next-generation of simulation software. It is web-based, and licensed under a usage based model (DARPA FANG competitors will use it for free.) It provides integrated requirements management, physics-model-based design, and supports cloud-based parallel simulation, for running stochastic optimizations. And, compared to traditional workstation-based tools, it may be quite a bit easier to learn and use, for people who are great engineers, but who don’t spend their entire worklife using simulation software.
A third META-compatible tool chain is available, commercially, from Dassault Systèmes. It’s based on their existing V6/3DEXPERIENCE products, with the addition of probabalistic, simulation-based verification capabilities across multiple physical domains, which were developed by DS under a DARPA META award.
If you happen to be a drive-train engineer, and might be interested in competing in the FANG Design Challenge, the first phase starts in mid-January, and has a prize of up to $1 million.
Dassault Systèmes Winning Program
Dassault Systèmes (DS) is used to working with large aerospace and defense companies, and they’ve seen many winning and losing programs. Winning Program is “Industry Experience” optimized to help companies better conceive, manage, and deliver complex development programs.
Industry Experience is the term DS uses to describe a bundled solution of software, services, best practices, processes, and essentially everything that a customer might need (and DS might be able to provide) to solve a particular industry-centric business problem. In the case of Winning Program, business problem is obvious: Companies want winning programs, not losing programs.
Winning program includes five major functional areas:
Proposal Development includes the necessary elements for planning and managing programs. It includes a variety of DS technologies, including ENOVIA, EXALEAD, and 3DSWYM.
Configuration Definition provides tools to create something similar in concept to the Behavioural Digital Aircraft from the CRESCENDO project. It is an ENOVIA based master digital mock-up (DMU) representing the behavior of the entire system.
System Trade Studies use multi-disciple analysis and optimization to explore design alternatives, using CATIA and SIMULIA (Abaqus, Fiper, and Isight) technology.
Production Trade Studies simulate production, sourcing, and support, using DELMIA.
Reason to Believe uses 3DVIA to create realistic contextual 3D presentations, based on the master DMU.
A major emphasis in Winning Program is connecting requirements with formal models, and using simulation to explore design alternatives during the conceptual phase.
Winning Program is a big thing, using a lot of DS technology and expertise. You won’t find a detailed spec sheet on the web for it, because any instance of it will be tuned to a customer’s (and a program’s) requirements. While DS strives to be a one-stop shop for technology, they have had quite a bit of success, particularly in the last few years, integrating competitive CAD and CAE software into their ENOVIA based solutions. It’s entirely reasonable to believe that companies that are not pure CATIA/ENOVIA shops might be able to work with DS to implement a custom Winning Program using a combination of their existing tools, and new DS tools.
Filed Under: Aerospace + defense, Design World articles, Simulation