Satellite Dynamics Toolbox (SDT)

 SIMULINK LIBRARY : SDTLIB_V1

This package contains the SIMULINK library of the SDT.

Documentation : download the SDTlib user guide (52 Mo) including the various tutorials and the on-line helps :

Demo : download the SDTlib demo (11.4 Mo, updated on October,21-th,2022) here.

Remark : all Matlab functions of the SDT V1.3 are included in this package (the reading of the SDT User Guide V1.4, available below, is recommended : )

Required configuration : SDTLIB_V1 was developed with MATLAB R2020b and requires the following toolboxes :

• control_toolbox
• robust_toolbox
• simulink
• simulink_control_design
• symbolic_toolbox

March, 22-th, 2021 :

• To download SDTLIB_V1_1_R2020b.zip, please send an email to daniel.alazard at isae-supaero.fr with the subject : Link to download SDTLIB_V1 (restrictions for non-academic and non-European partners may occur).

Refrences : if you publish work that uses these tools please refer to this web page and to the following papers :

• Alazard, Daniel and Sanfedino, Francesco. Satellite dynamics toolbox for preliminary design phase. (2020) In : 43rd Annual AAS Guidance and Control Conference, 30 January 2020 - 5 February 2020 (Breckenridge, United States).
• Sanfedino, Francesco and Alazard, Daniel and Pommier-Budinger, Valérie and Falcoz, Alexandre and Boquet, Fabrice.
  Finite element based N-Port model for preliminary design of multibody systems.
  (2018) Journal of Sound and Vibration, 415. 128-146. ISSN 0022-460X
• Chebbi, Jawhar and Dubanchet, Vincent and Perez Gonzalez, José Alvaro and Alazard, Daniel.
  Linear dynamics of flexible multibody systems : a system-based approach.
  (2017) Multibody System Dynamics, 41 (1). 75-100. ISSN 1384-5640
• Sanfedino, Francesco, Experimental validation of a high accuracy pointing system, PhD. Thesis, Université de Toulouse, ISAE-SUPAERO, 25 Avril 2019.

 MATLAB Toolbox : SDT v1.3

This package contains the SDT basic functions (MATLAB script file) to compute the (direct and indirect) linear dynamic model of spacecraft. This package is already included in the SIMULINK library SDTLIB_v0. This new version (V 1.3) allows parametric uncertainties to be taken into account (with full compatibility with the MATLAB Robust Control Toolbox). A user guide, some extra examples and a demo file are also included in the STDv1_3 package.

Download :

SDT_V1.3

STD V 1.3 : Matlab package

User Guide :

SDT User Guide V1.4

Reference :

ESA GNC 2008 (Tralee, Ireland)

PDF

If you publish work that uses this toolbox please refer to this web page and to the following paper :

• Alazard, D., Cumer, C., and Tantawi, K.,
  “Linear dynamic modeling of spacecraft with various flexible
  appendages and on-board angular momentums”.
  In Proceedings of the 7th International ESA Conference on Guidance,
  Navigation & Control Systems
  Tralee, Ireland, 1-5 June 2008

Description of main functions :

• main : is the main function,
• translate_dynamic_model : to translate a dynamic from one point to another,
• rotate_dynamic_model : to rotate a dynamic model,
• kinematic_model : to compute the kinematic model between 2 points of a body,
• antisym : to compute the antisymetric matrix associated with a vector.

This package contains also example data files :

• Spacecraft1.m is a data file relative to a spacecraft composed of a main body and two flexible appendage cantilevered on the main body,
• Spacecraft2.m is the same than Spacecraft1.m but the first appendage is connected to the main body through a pivot joint and tilted with a 10 degres angle,
• Spacecraft3.m is another data file describing the same spacecraft as Spacecraft2.m but using recursive call to MAIN function. Spacecraft3.m calls data file APPENDAGE1.m to describe the first flexible appendage.

Example :

>>mod1=main(’Spacecraft2’) ;

>>mod2=main(’Spacecraft3’) ;

>>figure,

>>sigma(mod1.DynamicModel-mod2.DynamicModel)

• Spacecraft5.m is the same than Spacecraft1.m but with 3 additionnal appendages corresponding to angular momentums along to X, Y and Z axes (to represent spinned RWA),
• FOUR_CMGs.m is a data file describing a platform fitting with four identical CMGs (Control Moment Gyros). The CMG is decribed by the data file dataCMG.m,
• SpaceRoboticArm.m is a date file describing a platform fitting a 6 d.o.f. rigid space robotic arm : the 6 links of the arm are described in the files Segment1.m, Segment2.m, ..., Segment6.m.

Example :

>> mod=main(’SpaceRoboticArm’) ;

>> mod.liste_IOs % To list and see the order of inputs and outputs of models

• Spacecraft1u.m is another data file describing the same structure than Spacecraft1.m but the main mechanical parameters are uncertain and defined by the function ureal. Then, the outputs of the toolbox main function are uncertain elements, matrices or models, compatible with the Robust Control Toolbox (LFT).

Example :

>> mod=main(’Spacecraft1u’) ;

>> sigma(mod.DynamicModel)

See also : README.m, demoSTD.m (inside the STD v1.3 package)