scenarioExtendingBoom

Overview

This scenario demonstrates the capabilities of Module: linearTranslationNDOFStateEffector, which represents an effector with up to \(N\) axis. The N-degree-of-freedom formulation allows the simulation of a component with any number of links with any number of degrees of freedom. The displacement axis and mass distribution of the rigid bodies are arbitrary.

The spacecraft comprises a rigid hub with a four-link appendage. The scenario starts with the links stowed at their nominal position and the spacecraft rotating in space. Then, each link extends, deploying the effector to full extension. The goal is to show the impact of the change in inertia due to the appendage deployment on the system’s angular velocity.

The script is found in the folder basilisk/examples and executed by using:

python3 scenarioExtendingBoom.py

The scenario outputs four plots: one for the time history of the displacements, another for displacement rates, one for the time history of the spacecraft’s attitude and another for the angular velocity. The scenario also creates a comprehensive Vizard simulation which creates appropriate to-scale models.

Illustration of Simulation Results

The simulation results are shown below. Each link extends with constant acceleration and deceleration until the end of the simulation. The key takeaway is how the magnitude of the spacecraft’s angular velocity diminishes as the inertia of the spacecraft increases with the extension of the effector.