On the integration of Cid’s radial intermediary (original) (raw)

Integration of Deprit's radial intermediary

Acta Astronautica, 2020

In Artificial Satellite Theory, for the so called main problem (the two-body problem is only perturbed by the equatorial planet's bulge) Deprit's intermediary plays an important role because of its simplicity and integrability while maintaining a similar structure to the original Hamiltonian. To integrate it, we prove that there is no need to introduce a generalizad Kepler's equation, but the classical Kepler's equation, which has been extensively studied for more than three centuries.

Universal formulation of quasi-Keplerian motion, and its applications

New Astronomy, 2009

We derive the universal solution to the Kepler-Coulomb problem with an additional inverse-square potential, valid for any type of orbit, and describe three prominent applications in astrodynamics: the relativistic precession of the apsides, the numerical integration of perturbed Kepler-Coulomb problems with a generalized leapfrog, and the averaged motion of earth-orbiting satellites with the J 2 perturbation. The modified orbital elements and Delaunay variables are presented as well.

On the radial intermediaries and the time transformation in satellite theory

Celestial Mechanics, 1986

Taking advantage of the radial intermediaries and the regularization and linearization methods, the zonal Earth satellite theory is studied in the polar nodal canonical set of variables (r, 0, v, R, | N). The variable 0 is eliminated in the first order of the Hamiltonian by applying Deprit's method. Then, the elimination of the perigee is carried out by another canonical transformation. As a consequence, a new radial intermediary, which contains all the J2,(n >~ 1) harmonics, is given. A comparison with the previous radial intermediaries of Cid and Lahulla, Deprit and Alfriend and Coffey is made. Finally, a regularizing transformation which allows us to linearize part of the radial intermediary is proposed, and an analytical study of this process is presented.

Orbit determination with the two-body integrals. II

Celestial Mechanics and Dynamical Astronomy, 2011

The first integrals of the Kepler problem are used to compute preliminary orbits starting from two short observed arcs of a celestial body, which may be obtained either by optical or radar observations. We write polynomial equations for this problem, that we can solve using the powerful tools of computational Algebra. An algorithm to decide if the linkage of two short arcs is successful, i.e. if they belong to the same observed body, is proposed and tested numerically. In this paper we continue the research started in , where the angular momentum and the energy integrals were used. A suitable component of the Laplace-Lenz vector in place of the energy turns out to be convenient, in fact the degree of the resulting system is reduced to less than half.

Analytical solutions of the relative orbital motion in unperturbed and in J 2 - perturbed elliptic orbits

Applied Mathematics and Nonlinear Sciences, 2017

This paper introduces a different approach to obtain the exact solution of the relative equations of motion of a deputy (follower) satellite with respect to a chief (leader) satellite that both rotate about central body (Earth) in elliptic orbits by using Laplace transformation. Moreover, the paper will take the perturbation due to the oblateness of the Earth into consideration and simulate this problem with numerical example showing the effect of the perturbation on the Keplerian motion. The solution of such equations in this work is represented in terms of the eccentricity of the chief orbit and its true anomaly as the independent variable.

Comment on ‘Conservative discretizations of the Kepler motion’

Journal of Physics A: Mathematical and Theoretical, 2010

We show that the exact integrator for the classical Kepler motion, recently found by Kozlov (J. Phys. A: Math. Theor. 40 4529-4539), can be derived in a simple natural way (using well known exact discretization of the harmonic oscillator). We also turn attention on important earlier references, where the exact discretization of the 4-dimensional isotropic harmonic oscillator has been applied to the perturbed Kepler problem.

Extended analytical formulae for the perturbed Keplerian motion under low-thrust acceleration and orbital perturbations

2021

This paper presents a collection of analytical formulae that can be used in the long-term propagation of the motion of a spacecraft subject to low-thrust acceleration and orbital perturbations. The paper considers accelerations due to: a low-thrust profile following an inverse square law, gravity perturbations due to the central body gravity field and the third-body gravitational perturbation. The analytical formulae are expressed in terms of non-singular equinoctial elements. The formulae for the third-body gravitational perturbation have been obtained starting from equations for the third-body potential already available in the literature. However, the final analytical formulae for the variation of the equinoctial orbital elements are a novel derivation. The results are validated, for different orbital regimes, using high-precision numerical orbit propagators.

A Note on the Use of Generalized Sundman Anomalies in the Numerical Integration of the Elliptical Orbital Motion

Abstract and Applied Analysis, 2014

The orbital motion around a central body is an interesting problem that involves the theory of artificial satellites and the planetary theories in the solar system. Nevertheless some difficult situations appear while studying this apparently simple problem, depending on each particular case. The real problem consists of searching the perturbed solution from a basic two-body motion problem. In addition, the perturbed problem must be solved using a numerical method and its efficiency depends on the selected coordinate system and the corresponding time. In fact, local and global errors are not necessarily homogeneously distributed over the orbit. In other words, there is a strong relationship between the spatial distribution of the selected points and the temporal independent variable. This is particularly dramatic in specially difficult cases. This issue leads us to consider different anomalies as temporal variables, searching for both precision and efficiency. Therefore, we are inter...

Computation of analytical solutions of the relative motion about a Keplerian elliptic orbit

Acta Astronautica, 2012

The purpose of this paper is to obtain a third-order expression, for the in-plane and outof-plane amplitudes, of the solutions of the elliptic Hill-Clohessy-Wiltshire non-linear equations. The resulting third-order solution is explicit in terms of true anomaly. The coefficients of the expansions are given as functions of the eccentricity e of the orbit of the leader (i.e., are valid for all values of e). For e ¼0 we recover the solution given by Richardson and Mitchell for the circular case; for ea0 the linear terms of the solution recover the solution found by Lawden for the linearised elliptic HCW equations, also known as the Tschauner-Hempel equations. In the last part of the paper we explain how a formal series solution of the elliptic HCW non-linear equations (in powers of the two amplitudes and the eccentricity) can be obtained, using the Lindstedt-Poincaré procedure.