Aerospace & Defense Technology - December 2021 - 8

CubeSat Technology
Controller
MissionComm
SystemResource
" ASIM "
ASIM_Plotter
Insights on the Cubesat
Architecture
MSV_Scheduler
Use Case, Orbit Definition and Earth-based Commands
Cmplt
ASIM
Setup
Mapper
" ASI...
Process_Task
*
/*
Process_Tas
Process_T
Battery_40_P
SubSystem
Mapper
Mapper2
*Sub
Mapper3
ASIM
" ASI
Plot_and_Display
Plot and Display
Figure 3. Architecture Model of the CubeSat in VisualSim Architect
daily observations. First, simulations
should be performed to foresee the
exact time when the CubeSat appears
over the horizon for every observation
event. Further, to store the results of
every incident, a template has to be
made for the operation report. The report
so generated can be used in the fu/*
Satellite Orbit Setup */
ID Satellite Orbit_ Sec Start_Orbit Incr_Orbit
 My_Sat_1
 My_Sat_1
 My_Sat_1
 My_Sat_1








Figure 4. Tasks scheduled to MSV scheduler

/* Text Template or File Path. First row = Field Names.
Satellite Time_on_Orbit Task_ID Task
My_Sat_1
My_Sat_1
My_Sat_1
My_Sat_1
My_Sat_1
My_Sat_1
My_Sat_1
Figure 5. Task ID table

/* Text Template or File Path. First row = Field Names. */
SubSystem_Arr
1
2
3
4
5
6
7
8
IMAGE
PROCESS
TACTICAL
SLEW
SUN_PT
SURVIVE
{ " Payload " , " CDH " , " ACS " , " EPS " , " TTC " , " Mission " }
{ " Payload " , " CDH " , " ACS " , " EPS " , " TTC " , " Mission " }
{ " Payload " , " ACS " , " EPS " , " Thermal " , " TTC " , " Mission " }
{ " Payload " , " CDH " , " EPS " , " Thermal " , " TTC " , " Mission " }
{ " Payload " , " CDH " , " ACS " , " EPS " , " Thermal " , " Mission " }
{ " Payload " , " CDH " , " ACS " , " EPS " , " Thermal " , " TTC " }
{ " Payload " , " CDH " , " ACS " , " Thermal " , " TTC " , " Mission " }
{ " CDH " , " ACS " , " EPS " , " Thermal " , " TTC " , " Mission " }
Figure 6. List of subsystems associated with each task
8
Intro
Cov














TTC
IMAGE
PROCESS
TTC
IMAGE
PROCESS
SUN_PT







*/
Priority Deadline ;
 
 
 
 
 
 
 




End_Orbit Task_ID_Arr




;
       
  
 

       

Working of the Subsystems
There are multiple subsystems such as
telemetry, tracking and command (TTC),
thermal, electrical power system (EPS),
altitude control system (ACS), command
and data handling (CDH), payload, and
mission communication. Each subsystem
is allocated a task to process.
The TTC and mission communication
subsystem observes and controls
the spacecraft's functions and communication
to and from the satellite. The
thermal subsystem controls and monitors
the temperature of all hardware
within the satellite. The EPS subsystem
manages peak, pulse and transient
power demands and the battery
charge/discharge cycles. It eliminates
spacecraft instability and performance
degradation.
ID Task
MEU
TTC
ACS measures orbit position, absolute
attitude, spacecraft rates and can also
control the orientation of the satellite.
CDH handles all the real-time operations
of the satellite and provide data
interfaces to all other systems. Payload
acquires scientific data and monitors
the health and progress of various subsystems.
As the satellite revolves around
the earth, it is expected to perform tasks
at specific times that need to be completed
within a time deadline.
www.aerodefensetech.com Aerospace & Defense Technology, December 2021
ToC
+
-
A
µ
ture for keeping track of the work performed,
as well as analyzing the data in
case of some operation failure. The status
of the satellite is summarized in the
housekeeping telemetry data. Housekeeping
telemetry consists of the parameters
and event messages. They are
processed and converted into the engiFigure
3 depicts the model of a CubeSat
developed using a modeling and
simulation software called VisualSim
Architect from Mirabilis Design Inc. The
designer can perform various experimentations,
conduct a variety of tradeoffs
for optimization and functional
studies to meet the specified requirements
before actual implementation in
real time. The designer gets a clear picture
of the performance and power optimization
to determine the trade-offs,
for instance the failure and functional
analysis, security, and a variety of other
attributes. It helps in exploration of the
architecture and to rectify faults at a
very early stage.
Mission
Comm
TTC
TT&C
Thermal
SubSystems
EPS
Thermal
EPS
ACS
ACS
CDH
CDH
Payload
Payload
neering or functional parameter values
needed to monitor the status of the
spacecraft platform, payload, and to recover
in case of anomalies.
È
http://www.aerodefensetech.com http://info.hotims.com/79420-922
Aerospace & Defense Technology - December 2021

Table of Contents for the Digital Edition of Aerospace & Defense Technology - December 2021
