Coefficients of the Equivalent Velocity Increment Estimator

These are the coefficients of the equivalent velocity increment estimator for minimum-time low-thrust transfers from an arbitrary elliptical orbit to the geostationary orbit. The estimator is a multivariate eleventh-degree polynomial regression model. The features (inputs) are the semi-major axis, eccentricity, inclination, and argument of periapsis of the initial orbit, i.e., a_0, e_0, i_0, and ω_0.

This estimator is suitable for the following ranges of the initial orbit (satisfy simultaneously):

• perigee altitude > 200 km
• a_0 < the radius of the geostationary orbit
• i_0 < 30.5 deg
• 165 deg < ω < 195 deg

In the estimation, the unit of a_0 is the radius of the geostationary orbit, the units of i_0 and ω_0 are both rad, and e_0 is dimensionless. The unit of the estimated equivalent velocity increment is m/s.

The format of the coefficient file is:

1. Column 1 is the power of a_0.
2. Column 2 is the power of e_0.
3. Column 3 is the power of i_0.
4. Column 4 is the power of ω_0.
5. Column 5 is the coefficient of this term.