Cartesian Coordinates¶

Functions for working with Cartesian state vectors and conversions.

State Conversions¶

state_koe_to_eci `builtin` ¶

state_koe_to_eci(x_oe: Union[ndarray, List], angle_format: AngleFormat) -> ndarray

Convert osculating orbital elements to Cartesian state.

Transforms a state vector from osculating Keplerian orbital elements to Cartesian position and velocity coordinates.

Parameters:

Name	Type	Description	Default
`x_oe`	`ndarray or list`	Osculating orbital elements `[a, e, i, RAAN, omega, M]` where `a` is semi-major axis (meters), `e` is eccentricity (dimensionless), `i` is inclination (radians or degrees), `RAAN` is right ascension of ascending node (radians or degrees), `omega` is argument of periapsis (radians or degrees), and `M` is mean anomaly (radians or degrees).	required
`angle_format`	`AngleFormat`	Angle format for angular elements (`RADIANS` or `DEGREES`).	required

Returns:

Type	Description
`ndarray`	numpy.ndarray: Cartesian state `[x, y, z, vx, vy, vz]` where position is in meters and velocity is in meters per second.

Example

import brahe as bh
import numpy as np

# Orbital elements for a circular orbit
oe = np.array([7000000.0, 0.0, 0.0, 0.0, 0.0, 0.0])  # a, e, i, RAAN, omega, M
x_cart = bh.state_koe_to_eci(oe, bh.AngleFormat.RADIANS)
print(f"Cartesian state: {x_cart}")

state_eci_to_koe `builtin` ¶

state_eci_to_koe(x_cart: Union[ndarray, List], angle_format: AngleFormat) -> ndarray

Convert Cartesian state to osculating orbital elements.

Transforms a state vector from Cartesian position and velocity coordinates to osculating Keplerian orbital elements.