latom.utils.spacecraft

@authors: Alberto FOSSA’ Giuliana Elena MICELI

Classes

ImpulsiveBurn(sc, dv)

ImpulsiveBurn class describes an impulsive burn.

Spacecraft(isp, twr[, throttle_min, m0, …])

Spacecraft class defines the spacecraft characteristics.
class latom.utils.spacecraft.Spacecraft(isp, twr, throttle_min=0.0, m0=1.0, m_dry=None, g=9.80665)[source]

Bases: object

Spacecraft class defines the spacecraft characteristics.

Parameters

  • isp (float) – Specific impulse [s]

  • twr (float) – Thrust over initial weight ratio [-]

  • throttle_min (float, optional) – Minimum throttle level [-]. Default is 0.0

  • m0 (float, optional) – Initial mass [kg]. Default is 1.0

  • m_dry (float or None, optional) – Dry mass [kg]. Default is None for which m_dry is set equal to m0/100

  • g (float, optional) – Central body surface gravity [m/s^2]. Default is g0

Variables

  • Isp (float) – Specific impulse [s]

  • twr (float) – Thrust over initial weight ratio [-]

  • m0 (float) – Initial mass [kg]

  • m_dry (float) – Dry mass [kg]

  • w (float) – Exhaust velocity [m/s]

  • T_max (float) – Maximum thrust [N]

  • T_min (float) – Minimum thrust [N]

update_twr(twr)[source]

Updates the boundaries value for the thrust throttle

Parameters

twr (float) – Thrust over initial weight ratio [-]

class latom.utils.spacecraft.ImpulsiveBurn(sc, dv)[source]

Bases: object

ImpulsiveBurn class describes an impulsive burn.

Parameters

  • sc (Spacecraft) – Instant of Spacecraft class

  • dv (float) – Change in velocity corresponding to the impulsive burn [m/s]

Variables

  • sc (Spacecraft) – Instant of Spacecraft class

  • dv (float) – Change in velocity corresponding to the impulsive burn [m/s]

  • mf (float) – Spacecraft final mass after the impulsive burn [kg]

  • dm (float) – Propellant mass required for the impulsive burn [kg]

static tsiolkovsky_mf(m0, dv, isp)[source]

Computes the final spacecraft mass for a given velocity change using the Tsiolkovsky rocket equation.

Parameters

  • m0 (float) – Initial spacecraft mass [kg]

  • dv (float) – Change in velocity [m/s]

  • isp (float) – Specific impulse of the spacecraft rocket engine [s]

Returns

mf – Final spacecraft mass [kg]

Return type

float

static tsiolkovsky_dv(m0, mf, isp)[source]

Computes the velocity change for a given initial and final spacecraft masses using the Tsiolkovsky rocket equation.

Parameters

  • m0 (float) – Initial spacecraft mass [kg]

  • mf (float) – Final spacecraft mass [kg]

  • isp (float) – Specific impulse of the spacecraft rocket engine [s]

Returns

dv – Change in velocity [m/s]

Return type

float