Digital Twin & Digital Engineering FAQ

How does Agile MBSE relate to Digital Engineering?

FAQ Variant(s): How does MBSE relate to Digital Twins?

Agile MBSE™ is a hybrid Systems Engineering process that combines the strengths and avoids the weaknesses of both "heavyweight" (a.k.a. "high ceremony" or "obese") Model-Based Systems Engineering (MBSE) processes and "lighweight" (a.k.a. "low ceremony" or "anorexic") Agile processes (e.g., Agile Software Development, Agile Engineering). The resultant "middleweight" Agile MBSE process is inherently more resilient (i.e., robust yet flexible) than either of its constituent processes, and consequently supports highly scaleable and simulatable system architectures. For more information about Agile MBSE, see PivotPoint FAQ: What is Agile MBSE™??

So how does MBSE in general, or Agile MBSE in particular, relate to architecting and designing Digital Twins?

Agile MBSE technologies provide the architecture infrastructure necessary for recursively scaling and simulating Digital Twins. Agile MBSE technologies are the distillation of a quarter century of lessons-learned from Model-Driven Development (MDD), Model-Based Systems Engineering (MBSE), and Agile/Lean Development technologies, and can provide the recursive architecture and design patterns needed to address the fractal Digital Twin System-of-System challenge.

How are massive Modeling & Simulation (ModSim) and Digital Twins related?

FAQ Variant(s): How does Parametric ModSim relate to Digital Twins?; How does Behavioral ModSim relate to Digital Twins?

Computer Modeling & Simulation (ModSim) of a system can be divided into two broad categories:

• Dynamic ModSim (a.k.a. Dynamic ModSim, Dynamic System Simulation, System Behavioral Simulation) refers to the capability of a computer program to execute the time-varying behavior of a system of interest. In general, with the exception of Use Case diagrams, SysML and UML 2 Behavior diagrams are potentially capable of Dynamic System Simulation.
• Mathematical ModSim (a.k.a. Mathematical ModSim, Parametric Simulation) refers to the capability of a computer program to execute a mathematical behavioral model of a system of interest, where the model is defined as a set of mathematical equations. When properly defined and applied, Parametric diagrams are capable of Mathematical ModSim; no other SysML or UML 2 diagrams are capable of this. The natural evolution of Mathematical M&S is Digital Physics, which is capable of modeling complex Systems-of-Systems using both deterministic and non-deterministic mathematics (the former are useful for Newtonial Mechanics with General Relativity extensions; the latter are useful for modeling Quantum Mechanics and Chaos Theory). For more information about Digital Physics, see the DT FAQ: What is Digital Physics? How does Digital Physics relate to Digital Engineering?.

So how do Mathematical ModSim and Behavioral ModSim relate to architecting and designing Digital Twins?

Massive Mathematical & Dynamic ModSim technologies provide the large-scale ModSim infrastructure for recursively simulating Physical Twins as Digital Twins. It is essential that mathematical (parametric) and dynamic (behavioral) simulations for Digital Twins are fully integrated and applied on a massive scale. Compare and contrast how massive data sets" and big data* fuel Machine Learning (ML) technology. Stated otherwise, if a Physical Twin is a "System-of-Systems", then a Digital Twin is a "Simulation-of-Simulations" for a "System-of-Systems".

What is Digital Physics? How does Digital Physics relate to Digital Engineering?

FAQ Variant(s): What is Digital Ontology?

In the context of physics, cosmology, and Digital Engineering, Digital Physics is a kind of digital ontology in which the physical universe is described by information. The first cogent expression of this "it from bit" idea may be attributed to the distinguished physicist John Archibald Wheeler in his seminal paper Information, Physics, Quantum: The Search for Links [Wheeler 1989], the Abstract of which is reproduced below:

This report reviews what quantum physics and information theory have to tell us about the age-old question, How come existence? No escape is evident from four conclusions: (1) The world cannot be a giant machine, ruled by any preestablished continuum physical law. (2) There is no such thing at the microscopic level as space or time or spacetime continuum. (3) The familiar probability function or functional, and wave equation or functional wave equation, of standard quantum theory provide mere continuum idealizations and by reason of this circumstance conceal the information-theoretic source from which they derive. (4) No element in the description of physics shows itself as closer to primordial than the elementary quantum phenomenon, that is, the elementary device-intermediated act of posing a yes-no physical question and eliciting an answer or, in brief, the elementary act of observer-participancy. Otherwise stated, every physical quantity, every it, derives its ultimate significance from bits, binary yes-or-no indications, a conclusion which we epitomize in the phrase, it from bit [italics added for emphasis].
— Information, Physics, Quantum: The Search for Links [Wheeler 1989]:

According to the Digital Physics theoretical approach, the physical universe can be considered to be the output of a deterministic or probabilistic computational device. Although many notable physicists and philosophers have contributed to the evolution of the Digital Physics concept, the most popular comprehensive expression of this approach to date is Stephen Wolfram's self-published and self-aggrandizing treatise: A New Kind of Science [Wolfram 2002].

It is important to note that Digital Physics is not restricted to deterministic mathematics; it can also be used to apply probabilistic (statistical), stochastic, and other non-determistic mathematics to physical models of Systems-of-Systems. Consequently, Digital Physics can use deterministic mathematics to specify classic Newtonian Mechanics and its General Relativity (spacetime) extensions; it can also use probabilistic and other non-determistic mathematics to specify Quantum Mechanics and Chaos Theory phenomena.

So how does Digital Physics relate to architecting and designing Digital Twins?

The vigorous usage of Digital Physics math libraries for Mathematical (Parametric) ModSim greatly increases the rigor and efficacy of Digital Engineering's massive ModSim approach for architecting and designing Digital Twins. Applying mathematical analysis techniques early and throughout the Digital Engineering System Development Life Cycle (SDLC) forces errors early in the SDLC, when they are exponentially more cost-effective to fix. For example, the International Space Station (ISS) could apply Digital Physics to Model & Simulate the 4D (spacetime) complexity of a space rendezvous mission. As a more ambitious example, the Space Force could apply Digital Physics to Model & Simulate the combinatorial explosion of hypothetical 4D space warfare scenarios.

How are Artificial Intelligence (AI), Machine Learning (ML) & Digital Engineering related?

FAQ Variant(s): How does Artificial Intelligence (AI) relate to Digital Twins?; How does Machine Learning (ML) relate to Digital Twins?

Machine Learning (ML) is the branch of Artificial Intelligence that studies computer algorithms that improve automatically (i.e., "learn") through experience. ML algorithms build mathematical model-based masive data sets, known as training data, in order to make predictions or decisions without having been explicitly programmed to do so. ML algorithms are used in a wide range of applications (e.g., computer vision, autonomous vehicles, cybersecurity) where it is difficult or impractical to develop conventional algorithms for the required work tasks. Data Mining is related to ML, and focuses on exploratory data analysis of massive data sets ("big data").

So how does AI in general, and Machine Learning in particular, relate to architecting and designing Digital Twins?

Artificial Intelligence (AI) & Machine Learning (ML) technologies provide the software infrastructure necessary for constructing intelligent ("smart") Physical Twins, and by extension their Digital Twin counterparts. Since AI & ML technologies are rapidly transforming how software-intensive Systems-of-Systems interact with humans, these complementary technologies will play a critical role in the evolution of Digital Twin technology.

DE FAQ: How are 3D CAD, 3D Printing & Digital Engineering related?

FAQ Variant(s): How does 3D CAD relate to Digital Twins?; How does 3D Printing relate to Digital Twins?

3D CAD (3D Computer Aided Design), 3D CAE (Computer Aided Engineering) and 3D CAM (Computer Aided Manufacturing) technologies are used to specify precise 3D models or mechanical, electrical, and electro-mechanical products for manufacturing. 3D Printing (a.k.a., Additive Manufacturing) technologies are capable of taking 3D CAD specifications and automatically construcing ("printing") them directly, with neither human intervention nor a separate traditional human-intensive manufacturing process (a.k.a., Subtractive Manufacturing).

So how do 3D CAD and 3D Printing relate to architecting and designing Digital Twins?

3D CAD & 3D Printing technologies provide the electro-mechanical infrastructure for the physical construction of Physical Twins, and by extension their Digital Twin counterparts. Since the [3D CAD] Design = Implementation [3D Printed Product] principle is rapidly transforming how we design and manufacture Systems-of-Systems, these complementary technologies will play a vital role in the evolution of Digital Twin technology.

How are Virtual Reality (VR) & Augmented Reality (AR) related to Digital Engineering?

FAQ Variant(s): How does Virtual Reality (VR) relate to Digital Twins?; How does Augmented Reality (AR) relate to Digital Twins?

In a Virtual Reality (VR) environment, the user's perception of reality is completely based upon digital ("virtual") information, rather than physical ("real") information. In an Augmented Reality (AR) environment, the user is provided with a physical information baseline, upon which is added a digital information layer that enhances their overall perception of reality. Stated otherwise, AR - VR = Physical Reality.

So how does VR in general, or AR in particular, relate to the architecting and designing of Digital Twins?

Virtual Reality (VR) & Augmented Reality (AR) technologies provide the simulation infrastructure for the massive simulations (Simulations-of-Simulations) required by Digital Twins to be indistinguishable from their Physical Twin counterparts. Since VR/AR technologies are rapidly transforming how we interact with Systems-of-Systems, they will play a critical role in the evolution of Digital Twin technology.