Path: SCPro/DynamicalModels
% Spacecraft attitude and orbit dynamics with time-varying mass.
This is a rigid body with an external force and torque input.
The position is in km. The gravity model is for a point mass.
The force and torque area constant across the integration time step.
The body has time varying mass but not inertia.
In this function d.mass is the dry mass. The fuel mass is in the state
vector x. If m is less than zero mDot is set to zero.
The function fDist (which should be a handle) is of the form
[force, torque] = MyFun( x, t, d )
You can add additional fields to d. force must be in N in the body
frame and torque in Nm in the body frame. This function allows you
to add forces and torques within the integration loop. This is
required for forces and torques that are functions of time or the
state vector.
--------------------------------------------------------------------------
Form:
d = RHSRigidBodyMass
[xDot, force, torque] = RHSRigidBodyMass( x, t, d )
--------------------------------------------------------------------------
-------
Inputs
-------
x (14,1) State vector [r;v;q;w;m] (km,km/s,,rad/s,kg)
t (1,1) Time (unused) (s)
d (1,1) Data structure for the simulation
.torque (3,1) External torque (Nm)
.force (3,1) External force (N)
.inertia (3,3) Vehicle inertia (kg-m^2)
.mass (1,1) Vehicle dry mass (kg)
.mu (1,1) Gravitational parameter (km^3/s^2)
.fDist (1,:) Disturbance function handle
.fDistData (1,1) Data structure for the disturbance
function
.mDot (1,1) Mass rate (kg/s)
-------
Outputs
-------
xDot (14,1) d[r;v;q;w;m]/ (km/s,km/s^2,,rad/s^2,kg/s)
force (3,1) Disturbance force (N)
torque (3,1) Disturbance torque (Nm)
--------------------------------------------------------------------------
AC: ACData/ACTConstants AerospaceUtils: Coord/QIToBDot SC: SCData/sCTConstants Common: CommonData/Constants Common: CommonData/xSplashSmall Common: Control/C2DZOH Common: Database/Constant Common: General/DeleteCell Common: Quaternion/QTForm Math: Linear/Mag Math: Linear/Skew Math: Linear/SkewSymm
Back to the SCPro Module page