Trajectory Design and Analysis for the IMAP Mission about the Sun-Earth L1 Libration Point

2022 ◽  
Author(s):  
Dawn P. Moessner ◽  
Brain W. Lathrop
Keyword(s):  
Libration Point ◽  
Trajectory Design ◽  
The Sun

Trajectory Design in the Sun-Earth-Moon System Using Lunar Gravity Assists

1998 ◽  
Vol 35 (2) ◽  
pp. 191-198 ◽  
Author(s):  
Roby S. Wilson ◽  
Kathleen C. Howell
Keyword(s):  
Trajectory Design ◽  
The Sun ◽  
Lunar Gravity ◽  
Moon System ◽  
Gravity Assists

Calculating the periods of radio signal transmission between two spacecrafts through the Venus atmosphere in the problem of studying its composition

2019 ◽  
Author(s):  
K.S. Fedyaev ◽  
V.V. Koryanov ◽  
S.A. Bober ◽  
V.A. Zubko ◽  
A.A. Belyaev
Keyword(s):  
Radio Signal ◽  
Initial Conditions ◽  
Libration Point ◽  
Signal Transmission ◽  
Energy Costs ◽  
The Sun ◽  
Initial State ◽  
Collinear Libration Point ◽  
Small Spacecraft ◽  
Atmosphere Of Venus

The paper considers calculating the periods of radio signal transmission through the atmosphere of Venus between a small spacecraft placed in a limited orbit in the vicinity of the collinear libration point of the Sun-Venus system and a Venus orbiter. The problem arises in the framework of the project under discussion to study the atmosphere of Venus. The possibility of transfers of these spacecrafts to the required orbits under various initial conditions is also studied. The impulses required for transferring to the specified orbits at the selected initial state vector, the most suitable for solving this problem are calculated. The duration and the number of transmission periods depending on the location of one of the spacecrafts in a limited orbit in the vicinity of the libration point L1 or L2 of the Sun-Venus system are analyzed. The influence of the shape of the orbiter near-Venusian orbit on the character and duration of the periods of transmission through the atmosphere of Venus is investigated. It is concluded that the location of a small spacecraft in a limited orbit in the vicinity of the L1 libration point of the Sun-Venus system is more advantageous compared to L2 both in terms of the duration and the number of the transmission periods as well as terms of the necessary energy costs.

scholarly journals Research on Control Method of Keeping Flight Formation by Using SDRE on the Sun-Earth Libration Points

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
He Zhenqi ◽  
Zhang Ke ◽  
Lv Meibai
Keyword(s):  
Control Method ◽  
Libration Point ◽  
Linear Quadratic Regulator ◽  
Transition Process ◽  
Continuous Control ◽  
The Sun ◽  
Nonlinear Dynamic Model ◽  
Linear Quadratic ◽  
State Dependent ◽  
Lqr Controller

Keeping the flying formation of spacecraft is a key problem which needs to be solved in deep space exploration missions. In this paper, the nonlinear dynamic model of formation flying is established and a series of transformations are carried out on this model equation. By using SDRE (State-Dependent Riccati Equation) algorithm, the optimal control of flying formation is realized. Compared with the traditional control method based on the average orbit elements and LQR (Linear Quadratic Regulator) control method, the SDRE control method has higher control precision and is more suitable for the advantages of continuous control in practical engineering. Finally, the parameter values of the sun-earth libration point L2 are substituted in the equation and simulation is performed. The simulation curves of SDRE controller are compared with LQR controller. The results show that the SDRE controllers time cost is less than the LQR controllers and the former’s fuel consumption is less than the latter’s in the system transition process.

scholarly journals Use of Libration-Point Orbits for Space Observatories

1990 ◽  
Vol 123 ◽  
pp. 391-395 ◽  
Author(s):  
Robert W. Farquhar ◽  
David W. Dunham
Keyword(s):  
Libration Point ◽  
Libration Points ◽  
Radiation Environment ◽  
The Sun ◽  
Halo Orbits ◽  
Libration Point Orbits ◽  
The Earth ◽  
Space Observatories

AbstractThe Sun-Earth libration points, L1 and L2, are located 1.5 million kilometers from the Earth towards and away from the Sun. Halo orbits about these points have significant advantages for space observatories in terms of viewing geometry, thermal and radiation environment, and delta-V expediture.

Sign in / Sign up

Export Citation Format

Share Document