Illustrates how to add a Module: GravityGradientEffector to the spacecraft while a Hill-frame pointing control solution is active. This script expands on scenarioAttitudeGuidance sets up a 6-DOF spacecraft which is orbiting the Earth. More illustrations on using the gravity gradient torque effector can be found in the modules _UnitTest folder.
The script is found in the folder
basilisk/examples and executed by using:
The simulation layout is shown in the following illustration. The Module: GravityGradientEffector is added to the spacecraft to create a position depended external torque. This
Illustration of Simulation Results¶
In this simulation the reference frame is not aligned with the Hill frame, but rather it has a fixed angular offset along the 2nd body axis. As the Body frame inertia tensor is diagonal, this reference orientation represents a non-equilibrium gravity gradient torque orientation. Thie simulation results are shown in the following figures:
Where in scenarioAttitudeGuidance the attitude error asymptotically converged to zero, with the gravity gradient torque the closed loop dynamics is now only Lagrange stable or bounded.
The scenarios can be run with the followings setups parameters:
show_plots (bool) – Determines if the script should display plots