# scenarioFormationMeanOEFeedback¶

## Overview¶

This script sets up a formation flying scenario with two spacecraft. The deputy spacecraft keeps a given mean orbital element difference based on Lyapunov control theory.

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

python3 scenarioFormationMeanOEFeedback.py


The simulation layout is shown in the following illustration. Two spacecraft are orbiting the earth at close distance. Only $$J_2$$ gravity perturbation is included. Each spacecraft sends a Module: simpleNav output message of type NavAttMsgPayload message at a certain period to Module: meanOEFeedback, where mean orbital element difference is calculated and necessary control force is output to extForceTorque module.

## Illustration of Simulation Results¶

show_plots = True, useClassicElem = True


In this case, target orbital element difference is set based on classical orbital element. This resulting feedback control error is shown below.

show_plots = True, useClassicElem = False


In this case, target orbital element difference is set based on equinoctial orbital element. This resulting feedback control error is shown below.

scenarioFormationMeanOEFeedback.run(show_plots, useClassicElem, numOrbits)[source]

At the end of the python script you can specify the following example parameters.

Parameters
• show_plots (bool) – Determines if the script should display plots

• useClassicElem (bool) – Determines if classic orbital element is used