CL_man_dvSmaEccv

Description

• Computes the maneuver that simultaneously changes the semi-major axis and the eccentricity vector (eccentricity and argument of periapsis).

  The orbits are defined by 3 parameters:

  sma: Semi major axis (positive),

  ecc: Excentricity,

  pom: Argument of periapsis = angle between some arbitrary direction in the orbit plane and the periapsis.

  There can be 0, 1 or 2 solutions.

  If the initial and final orbits don't intersect, no solution is returned.

  If res is equal to "opt", the solution returned is the one with the smallest deltav norm.

• Notes:

  - The orbits can be of any type (elliptical or hyperbolic).

  - If the number of intersections is infinite, no solution is returned (numsol == 0).

  - If there are no solutions, all the results are set to %nan (except numsol).

  - If there is 1 solution, the results for the second maneuver (solution "b") are set to %nan.

  - If there are 2 solutions, solution "a" is the one with the smallest |deltav|.

Parameters

smai:

Semi major axis of initial orbit [m] (1xN or 1x1)

ecci:

Excentricity of initial orbit (1xN or 1x1)

pomi:

Argument of periapsis of initial orbit [rad] (1xN or 1x1)

smaf:

Semi major axis of final orbit [m] (1xN or 1x1)

eccf:

Excentricity of final orbit (1xN or 1x1)

pomf:

Argument of periapsis of final orbit [rad] (1xN or 1x1)

res:

(string, optional) Type of output: "opt", "all" or "s"

mu :

(optional) Gravitational constant. [m^3/s^2] (default value is %CL_mu)

deltav:

Norm of velocity increment (minimum cost) [m/s] (1xN)

dv, dva:

Velocity increment (cartesian coordinates) in "qsw" local frame [m/s] - solution "a" (3xN)

pso, psoa:

True argument of latitude [rad] - solution "a" (1xN)

dvb:

Velocity increment (cartesian coordinates) in "qsw" local frame [m/s] - solution "b" (3xN)

psob:

True argument of latitude [rad] - solution b (1xN)

numsol:

Number of solutions: 0, 1, or 2 (1xN)

Authors

• CNES - DCT/SB

See also

• CL_gm_intersectCoplanOrb

Examples

// Define 2 elliptical orbits that intersect [smai, ecci] = CL_op_rarp2ae(7378.e3, 6878.e3); [smaf, eccf] = CL_op_rarp2ae(7378.e3, 6868.e3); pomi = 0; pomf = CL_deg2rad(1); // Compute maneuver (minimal cost) [deltav, dv, pso] = CL_man_dvSmaEccv(smai, ecci, pomi, smaf, eccf, pomf) // Check result [posi, veli] = CL_oe_kep2car([smai; ecci; 0; pomi; 0; CL_kp_v2M(ecci, pso-pomi)]); [posf, velf] = CL_oe_kep2car([smaf; eccf; 0; pomf; 0; CL_kp_v2M(eccf, pso-pomf)]); posf - posi // => 0 dv - (CL_fr_inertial2qsw(posi,veli,velf) - CL_fr_inertial2qsw(posi,veli,veli)) // => 0