Abstract We present here a method and some tools developed to build linear models of multi-body systems for space applications (typically satellites). The multi-body system is composed of a main body (hub) fitted with rigid and flexible appendages (solar panels, antennas, propellant tanks, …etc). Each appendage can be connected to the hub by a cantilever joint or a pivot joint. More generally, our method can be applied to any open mechanical chain. In our approach, the rigid six degrees of freedom (d.o.f) (three translational and three rotational) are treated all together. That is very convenient to build linear models of complex multi-body systems. Then, the dynamics model used to design AOCS, i.e. the model between forces and torques (applied on the hub) and angular and linear position and velocity of the hub, can be derived very easily. This model can be interpreted using block diagram representation.
[1]
Anneli Folkesson,et al.
Numerical methods for engineers
,
2007
.
[2]
Dare A. Wells,et al.
Schaum's outline of theory and problems of Lagrangian dynamics : with a treatment of Euler's equations of motion, Hamilton's equations and Hamilton's principle
,
1967
.
[3]
Naresh K. Sinha,et al.
Modern Control Systems
,
1981,
IEEE Transactions on Systems, Man, and Cybernetics.
[4]
C. Manceaux-Cume.
Minimal LFT form of a spacecraft built up from two bodies
,
2001
.
[5]
J.-F. Magni.
Extensions of the linear fractional representation toolbox (LFRT)
,
2004,
2004 IEEE International Conference on Robotics and Automation (IEEE Cat. No.04CH37508).
[6]
P. N. Paraskevopoulos,et al.
Modern Control Engineering
,
2001
.