apogee-orbit

Orbital propagation and attitude control for solar panel optimization.

Installation¶

uv sync --package apogee-orbit

CLI Usage¶

# Full simulation (launch + orbit)
uv run apogee-orbit --h-target-km 200 --payload-kg 5000

# With plots
uv run apogee-orbit --h-target-km 200 --payload-kg 5000 --plot

# Standalone (skip launch)
uv run apogee-orbit --r-m 6570000 --nu-initial-deg 15 --plot

Python API¶

from apogee_orbit import calculate_orbit_yaw

result = calculate_orbit_yaw(
    h_target_km=200,
    payload_kg=5000,
    sun_vector=(1, 0, 0),
)

print(f"Period: {result.orbit_params['period_s']:.0f} s")

Modules¶

Module	Purpose
core	EquatorialOrbit class
attitude	Yaw steering algorithm
simulator	Full orbit simulation
plotting	3D visualization

Key Concepts¶

Yaw Steering Law¶

Rotates satellite about nadir axis to keep sun in body X-Z plane:

\[ \psi = \arctan2(s_{y,\text{local}}, s_{x,\text{local}}) \]

LVLH Frame¶

Z (Nadir): Points to Earth center
X (Velocity): Along velocity vector
Y (Cross-track): Completes right-hand system