Path: SC/Dynamics
% Right-hand-side for spacecraft attitude with reaction wheels.
The wheels can have damping and Coulomb friction and stiction.
If you call it without any arguments it will return the default data
structure.
The inertia of the body does not include the RWA polar inertia.
RWA stands for reaction wheel assembly.
The default data structure is for 3 orthogonal reaction wheels.
Uses ReactionWheelFriction.m
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Form:
d = RHSReactionWheel; % To get the data structure
[xDot,hECI] = RHSReactionWheel x, t, d )
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Inputs
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x (7+n,1) State vector [q;omega;omegaRWA]
t (1,1) Time (unused)
d (.) Data structure
.inr (3,3) Body inertia matrix
.torque (3,1) External torque in the body frame
.inrRWA (n,1) Polar inertia of each wheel
.torqueRWA (n,1) Torques on each wheel
.uRWA (3,n) Unit vectors for the RWA
.friction (.) Friction data structure
.useFriction (1,1) true means use friction
.states {:} State names (names for 3 wheels)
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Outputs
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xDot (7+n,1) State vector derivative d[q;omega;omegaRWA]/dt
hECI (3,1) Inertial angular momentum
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AerospaceUtils: Coord/QIToBDot SC: Actuator/ReactionWheelFriction Common: Quaternion/QTForm
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