Orbital Coordinate System
Author: Tianjiang Shuo
Website: https://cislunarspace.cn
Definition
A local reference frame centered at the spacecraft's center of mass, used to describe thrust direction. The paper defines the Ay1 axis as pointing from the Moon's center to the spacecraft, the Ax1 axis as perpendicular to Ay1 in the direction of motion, and Az1 by the right-hand rule. Thrust direction is described by two angles: vartheta as the angle between the thrust vector and the Ay1 axis (in-plane angle), and psi as the angle between the thrust projection on the x1Az1 plane and the negative Ax1 axis (out-of-plane angle). A coordinate transformation matrix projects thrust components into the inertial frame to establish the three-dimensional dynamics.
Application Value
This concept provides fundamental support in cislunar space research and mission design. In practical applications, the appropriate analysis method should be selected based on specific mission scenarios and constraints.
Related Concepts
- On-Board Software
- Barycentric Coordinate Time, TCB
- Horizontal Coordinate System
References
- 周净扬和周荻 - 2007 - 月球探测器软着陆精确建模及最优轨道设计