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M&S-BASED SPACE REMOTE SENSOR DESIGN & ANALYSIS 
YANG Lei 
College of Astronautics & Material Technology, National University of Defence Technology, Changsha 410073, China 
- craftyang@163.com 
KEY WORDS: MBSE; Virtual Prototype; Modelling and Simulation; Performance Aanalysis; MTF; Zemike Polynomial 
ABSTRACT: 
Space Remote Sensor (SRS) is a complicated system involving optics, mechanism, electric and thermal. Utilizing Modelling and 
Simulation (M&S) in the development of SRS can expedite the design process, reduce costs and minish risks. This article first 
introduces the concept of Model Based System Engineering (MBSE), then expatiates the characteristics of VP. MBSE provides a 
methodology for complicated and large scale systems. VP can act as the connection between design, analysis and manufacture. After 
that, the article gives an example to illustrate how to utilize M&S in the development of SRS. The author first builds a simple virtual 
prototype (VP) of SRS. Then the performance change of SRS under sun radiation is analyzed by the VP. The simulation results show 
that the performance of SRS is not sensitive to radial temperature gradient 
1. INTRODUCTION 
SRS is a complicated system involving optics, mechanism, 
electric and thermal. The development of SRS is a process of 
high costs and risks because of the special working environment 
of SRS. Once the SRS is launched, it is very difficult to repair 
or update it. Constrain by time, finance, technical conditions 
and other factors, it is very difficult to use physical prototype to 
forecast the performance of SRS in space environment. Under 
such circumstances, simulation is a good choice. M&S can 
support the whole lifecycle of SRS from design to analysis and 
to manufacture. NASA’s Next Generation Space Telescope 
(NGST) project is a good paradigm of utilizing M&S in the 
development of SRS (Gary Mosier, 2000; Olivier L. de Week, 
2000) and shows the merit of M&S. 
The development of SRS can be considered as an flow of 
information between different departments. M&S can act as the 
connection between different development stages. In this article, 
MBSE (Jeff A. Estefan, 2007) and VP are introduced first. 
After that, the method to design and analysis SRS using VP is 
introduced by an example. 
2. MBSE 
MBSE is a new methodology based on modelling and 
simulation. The core idea of MBSE is to let model play the key 
role in the analysis, function decomposition, design, and 
development of systems. The main elements of MBSE are 
process, method and tool. MBSE is the combination of M&S 
and system engineering. MBSE represents the transition from 
the development pattern which focuses on documents to the one 
focus on models (Figure 1). 
Figure 1. MBSE causes the change of development pattern 
M&S can give support to the whole lifecycle of system 
development: 
1) Model is the best media to record knowledge. In any 
organization, the most valuable thing is the accumulated 
knowledge. Model is the best media to record these knowledge 
with accurate syntax and semantics. 
2) Models can foster intercommunions between stuffs. Every 
research domain has it’s own working language. Most of the 
languages are native languages and informal. Thus lead to the 
comprehension difficulty between different domain stuffs. 
Models are represented by some formal, accurate, universal 
modelling languages and are the best communication tools 
between people of different research domains. 
3) M&S can be used to compare different design plans. Before 
the system is developed, even the users may not very clear 
about the detail of the system. Using M&S, developers can 
provide users a VP to help them realize the structures, 
behaviours and appearances of the system. 
4) M&S can help to choose systemic parameters. The 
descriptions of systems are not complete at the beginning of 
design. Some systemic parameters can hardly be decided. M&S 
can help designers reduce the design space. 
5) M&S is the core technology in the integration of design, 
analysis and manufacture. With the development of CAx, DFx 
and numeric manufacture, the integration of design, analysis 
and production is possible. 
3. VIRTUAL PROTOTYPE 
VP technology is an important part of M&S. VP model is an 
integration of different domain digital models. VP model 
contains the all primary characteristics of the real product. 
Compared with other simulation model, VP has the following 
specialties: 
1) VP model targets certain product. There are strong 
heterogeneity and coupling between different sub-system 
models of different domains. Usually, these models are 
modeling with different tools.