Aerospace and Electronic Systems Magazine April 2018 - 26

Model-Based Systems Engineering in Small Satellite Conceptual Design
phasizes the formal capture, description, and communication of
systems specifications. Diagrams can be constructed to describe
various systems based on structure and behavior.

SYSML DIAGRAMS
Systems engineers use common drawing tools for diagrams in
which precise meanings are not associated with each type of arrows and blocks. The purpose of the diagram is to support a paragraph or a document. The information model distinguishes SysML
from conventional drawing and simulation tools in the following
ways:
C

C

C

Figure 1.

C

Satellite design project activities and MBSE artifacts.

various circumstances and scopes. Certain testing activities during the assembly integration and testing phase are supported by
SysML diagrams, enabling test-case design and tracing them back
toward the requirements for conformance.

MODELING APPROACH
The promoters of MBSE advocate the benefits of using SysML
and similar modeling paradigms. However, in practice, we have
found that the aerospace industry is less familiar with the inherent advantages and usefulness of the MBSE approach. Aerospace
system engineers mostly have electrical and mechanical engineering backgrounds. They are inherently less familiar with software
engineering and object-oriented programming (OOP) model.
Aerospace system engineers usually prefer conventional ways
of doing SE through the tools they are most familiar with, such as
the Microsoft Office tool chain (Excel, Word, and Visio), STK, and
MATLAB. Enabling our system engineers to adopt SysML is the
foremost challenge for us. To fill the gap between the traditional
document-based approach and the model-based approach, we devised a two-step modeling approach for current and future projects
in the Pakistan National Student Satellite Program (PNSSP) as
shown Figure 2. In the first stage, the NSS-1 model repository is
developed, in which we partially incorporate the model-based approach, along with integration of existing SE resources (documents
and tools). Meanwhile, the system engineers are being taught about
MBSE methodologies, modeling languages, and tools. In the next
stage, NSS-2 will fully incorporate the MBSE approach.

A formal information model is given for underlying diagrams.
The SysML model of a system can be tested to ensure that
the models are complete and consistent.
The SysML diagrams have robust semantics and details captured for formal specifications.
The SysML model can be used to interface and interoperate
with other tools and data sources. This also assists the integrated product development process [9].

ASSOCIATED CHALLENGES
Although MBSE has a long history [11], it has not yet fully taken
hold within satellite SE. One of the reason is that MBSE needs
some other disciplines' knowledge, particularly from modeling
and software engineering, which is usually absent among conventional system engineers belonging to core engineering disciplines
(electrical and mechanical). Conventional system engineers are
inherently uncomfortable with SysML diagrams and follow conventional ways of writing design documents.

OMG SYSML
OMG SysML is a unified modeling language (UML)-based standard graphical language for modeling systems. SysML is composed of graphical notations and an information model that em26

Figure 2.

Modeling approach adopted for PNSSP.

IEEE A&E SYSTEMS MAGAZINE

APRIL 2018



Table of Contents for the Digital Edition of Aerospace and Electronic Systems Magazine April 2018

No label
Aerospace and Electronic Systems Magazine April 2018 - No label
Aerospace and Electronic Systems Magazine April 2018 - Cover2
Aerospace and Electronic Systems Magazine April 2018 - 1
Aerospace and Electronic Systems Magazine April 2018 - 2
Aerospace and Electronic Systems Magazine April 2018 - 3
Aerospace and Electronic Systems Magazine April 2018 - 4
Aerospace and Electronic Systems Magazine April 2018 - 5
Aerospace and Electronic Systems Magazine April 2018 - 6
Aerospace and Electronic Systems Magazine April 2018 - 7
Aerospace and Electronic Systems Magazine April 2018 - 8
Aerospace and Electronic Systems Magazine April 2018 - 9
Aerospace and Electronic Systems Magazine April 2018 - 10
Aerospace and Electronic Systems Magazine April 2018 - 11
Aerospace and Electronic Systems Magazine April 2018 - 12
Aerospace and Electronic Systems Magazine April 2018 - 13
Aerospace and Electronic Systems Magazine April 2018 - 14
Aerospace and Electronic Systems Magazine April 2018 - 15
Aerospace and Electronic Systems Magazine April 2018 - 16
Aerospace and Electronic Systems Magazine April 2018 - 17
Aerospace and Electronic Systems Magazine April 2018 - 18
Aerospace and Electronic Systems Magazine April 2018 - 19
Aerospace and Electronic Systems Magazine April 2018 - 20
Aerospace and Electronic Systems Magazine April 2018 - 21
Aerospace and Electronic Systems Magazine April 2018 - 22
Aerospace and Electronic Systems Magazine April 2018 - 23
Aerospace and Electronic Systems Magazine April 2018 - 24
Aerospace and Electronic Systems Magazine April 2018 - 25
Aerospace and Electronic Systems Magazine April 2018 - 26
Aerospace and Electronic Systems Magazine April 2018 - 27
Aerospace and Electronic Systems Magazine April 2018 - 28
Aerospace and Electronic Systems Magazine April 2018 - 29
Aerospace and Electronic Systems Magazine April 2018 - 30
Aerospace and Electronic Systems Magazine April 2018 - 31
Aerospace and Electronic Systems Magazine April 2018 - 32
Aerospace and Electronic Systems Magazine April 2018 - 33
Aerospace and Electronic Systems Magazine April 2018 - 34
Aerospace and Electronic Systems Magazine April 2018 - 35
Aerospace and Electronic Systems Magazine April 2018 - 36
Aerospace and Electronic Systems Magazine April 2018 - 37
Aerospace and Electronic Systems Magazine April 2018 - 38
Aerospace and Electronic Systems Magazine April 2018 - 39
Aerospace and Electronic Systems Magazine April 2018 - 40
Aerospace and Electronic Systems Magazine April 2018 - 41
Aerospace and Electronic Systems Magazine April 2018 - 42
Aerospace and Electronic Systems Magazine April 2018 - 43
Aerospace and Electronic Systems Magazine April 2018 - 44
Aerospace and Electronic Systems Magazine April 2018 - 45
Aerospace and Electronic Systems Magazine April 2018 - 46
Aerospace and Electronic Systems Magazine April 2018 - 47
Aerospace and Electronic Systems Magazine April 2018 - 48
Aerospace and Electronic Systems Magazine April 2018 - 49
Aerospace and Electronic Systems Magazine April 2018 - 50
Aerospace and Electronic Systems Magazine April 2018 - 51
Aerospace and Electronic Systems Magazine April 2018 - 52
Aerospace and Electronic Systems Magazine April 2018 - 53
Aerospace and Electronic Systems Magazine April 2018 - 54
Aerospace and Electronic Systems Magazine April 2018 - 55
Aerospace and Electronic Systems Magazine April 2018 - 56
Aerospace and Electronic Systems Magazine April 2018 - 57
Aerospace and Electronic Systems Magazine April 2018 - 58
Aerospace and Electronic Systems Magazine April 2018 - 59
Aerospace and Electronic Systems Magazine April 2018 - 60
Aerospace and Electronic Systems Magazine April 2018 - Cover3
Aerospace and Electronic Systems Magazine April 2018 - Cover4
http://www.brightcopy.net/allen/aesm/34-2s
http://www.brightcopy.net/allen/aesm/34-2
http://www.brightcopy.net/allen/aesm/34-1
http://www.brightcopy.net/allen/aesm/33-12
http://www.brightcopy.net/allen/aesm/33-11
http://www.brightcopy.net/allen/aesm/33-10
http://www.brightcopy.net/allen/aesm/33-09
http://www.brightcopy.net/allen/aesm/33-8
http://www.brightcopy.net/allen/aesm/33-7
http://www.brightcopy.net/allen/aesm/33-5
http://www.brightcopy.net/allen/aesm/33-4
http://www.brightcopy.net/allen/aesm/33-3
http://www.brightcopy.net/allen/aesm/33-2
http://www.brightcopy.net/allen/aesm/33-1
http://www.brightcopy.net/allen/aesm/32-10
http://www.brightcopy.net/allen/aesm/32-12
http://www.brightcopy.net/allen/aesm/32-9
http://www.brightcopy.net/allen/aesm/32-11
http://www.brightcopy.net/allen/aesm/32-8
http://www.brightcopy.net/allen/aesm/32-7s
http://www.brightcopy.net/allen/aesm/32-7
http://www.brightcopy.net/allen/aesm/32-6
http://www.brightcopy.net/allen/aesm/32-5
http://www.brightcopy.net/allen/aesm/32-4
http://www.brightcopy.net/allen/aesm/32-3
http://www.brightcopy.net/allen/aesm/32-2
http://www.brightcopy.net/allen/aesm/32-1
http://www.brightcopy.net/allen/aesm/31-12
http://www.brightcopy.net/allen/aesm/31-11s
http://www.brightcopy.net/allen/aesm/31-11
http://www.brightcopy.net/allen/aesm/31-10
http://www.brightcopy.net/allen/aesm/31-9
http://www.brightcopy.net/allen/aesm/31-8
http://www.brightcopy.net/allen/aesm/31-7
https://www.nxtbookmedia.com