Multiple Gravity Assist Interplanetary Trajectories

OV Papkov

• Publisher: Routledge
• Year: 2017
• ISBN:
  9781351429702
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Physics
• Index: Physics

Reflecting the results of twenty years; experience in the field of multipurpose flights, this monograph includes the complex routes of the trajectories of a number of bodies (e.g., space vehicles, comets) in the solar system.
A general methodological approach to the research of flight schemes and the choice of optimal performances is developed. Additionally, a number of interconnected methods and algorithms used at sequential stages of such development are introduced, which allow the selection of a rational multipurpose route for a space vehicle, the design of multipurpose orbits, the determination of optimal space vehicle design, and ballistic performances for carrying out the routes chosen. Other topics include the practical results obtained from using these methods, navigation problems, near-to-planet orbits, and an overview of proven and new flight schemes.

1. DYNAMIC SCHEME, MODELS, AND METHODS OF ANALYSIS OF SPACECRAFT TRAJECTORIES USING GRAVITY ASSIST MANEUVERS

The motion of the spacecraft in the solar system is controlled by various physical forces. These are the gravitational forces exerted by the sun and natural celestial bodies in the solar system; environmental forces (atmospheric, electromagnetic, forces of solar pressure, etc.); and the jet power of the spacecraft’s engines.

Depending on the purpose of the mission, its path, and duration, different physical forces can become decisive in determining the spacecraft’s trajectory. In accordance with these circumstances, different models can be used to examine the spacecraft’s motion in space [1, 2, 3, 4, 7, 8, 9, 10, 12, 15, 26].

In the general case, determining the trajectory of spacecraft motion in the solar system under the effect of several attracting bodies is a very complicated computational problem which can be solved only by numerical integration. At the same time, a comprehensive analysis of interplanetary flight trajectories requires examination of a great number of options. This can only be achieved by using approximate models and methods, which result in an effective and clear analysis.

At the initial stage of examining the motion of a spacecraft with high-thrust engines in an interplanetary flight from the departure planet to the target celestial body (planet, comet, asteroid), a model accounting for the thrust and gravitational forces of planets is commonly used. In this model, the spacecraft is regarded as a “zero-mass” body (that is, it experiences the gravitation of other bodies, but does not attract them) [12].

The great distances between the attracting masses in the solar system, and the ratios between the masses of planets and the sun allow the gravity field in the solar system to be represented as the gravity field of the sun (heliosphere) and the gravity fields of the planets, each of which is restricted to the planetary gravisphere. Various methods are known to describe the boundaries of these gravispheres: the planets’ spheres of gravitational activity (or Laplace’s gravispheres), gravispheres of planet activity, Hill’s spheres, spheres of minimum deviations [1, 8, 30, 61].

In such models, the interplanetary trajectory of the spacecraft is represented by a series of segments of undisturbed Keplerian motion in the gravispheres of relevant celestial bodies, while on the boundaries of these segments, the trajectory passes from the gravisphere into the heliosphere and vice versa. In accordance with this division, the so-called “external” and “internal” problems of interplanetary flight are considered (that is, flights in the central fields of the sun and corresponding planets) [3, 12, 17, 18, 19, 20, 21, 22, 30].

Studies of interplanetary flight with gravity assist maneuvers are known to deal with cases where the spacecraft on its way from one celestial body to another approaches a third attracting body (e.g. a planet), which brings about a significant change in the spacecraft trajectory. Strictly speaking, in add...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Introduction
• 1. Dynamic scheme, models, and methods of analysis of spacecraft trajectories using gravity assist maneuvers
• 2. Methods and algorithms for the development of optimal multi-purpose missions
• 3. Ballistic methods in multi-purpose interplanetary spacecraft design
• 4. Analysis of multi-purpose schemes of interplanetary flight
• 5. Multi-purpose flights in planetary-satellite systems
• 6. Flights to small bodies in the solar system
• 7. Solution of navigational problems for multi-purpose missions at near-planet segments of the flight trajectory
• References
• Author index
• Subject index