Design of Aerogravity Assist Transfer Trajectory for Ivar Asteroid Rendezvous Mission

Paper number

IAC-05-A3.4.03

Author

Mr. Qiao Dong, Harbin Institute of Technology, China

Coauthor

Mr. Cui Hutao, Harbin Institute of Technology, China

Coauthor

Mr. Pingyuan Cui, Harbin Institute of Technology, China

Year

2005

Abstract

In interplanetary exploration missions, the gravity assist is an available approach for reducing launch energy and total velocity increments. The gravity assist technique is limited, however, by the turn angle of hyperbolic excess velocity vector that can be affected by a flyby body. This turn angle depends on the size and mass of the planet and the magnitude of hyperbolic excess velocity vector. In recent years, a new concept in interplanetary exploration missions has been developed. This new concept, namely aerogravity assist (AGA), utilizes atmospheric flight in order to augment the gravitational bending of heliocentric velocity during a planetary encounter. In this paper, some characteristics of aerogravity assist transfer trajectory are analyzed and the trajectory profile to rendezvous with 1627 Ivar asteroid using aerogravity assist technique is designed.

   The maximum atmospheric turn angle and velocity increments for aerogravity assist are analyzed. Then the patching condition for designing aerogravity assist transfer trajectory is presented. This patching condition is the significant principle for aerogravity assist trajectory design and studies. It can be used to find potential trajectories to next target at an encounter. 

   Based on patched conic theory and patching condition of aerogravity assist transfer trajectory, the trajectory profile to rendezvous with Ivar is designed. Firstly, the admissible launch opportunities and potential aerogravity assist or gravity assist targets are found by plotting the “pork-chop plots” and using global optimal search algorithm. Then, several segments of transfer trajectory are patched by patching conditions. Some initial designing parameters of trajectory profile can be obtained. Finally, the optimal transfer trajectory profile to rendezvous with Ivar asteroid with aerogravity assist and gravity assist technique is found by SQP method. The calculation demonstrates that the trajectory profile with aerogravity assist, compared with 2:1 Delta-VEGA, can reduce total velocity increments from 5.389km/s to 4.564km/s and the launch energy C3 from 26.356 km2/s2 to 9.379 km2/s2.

Abstract document

IAC-05-A3.4.03.pdf

Manuscript document

IAC-05-A3.4.03.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.