Design and simulation of the helix maneuvering program for moving centroid reentry vehicles

The subject investigated in this paper is a moving centroid reentry vehicle which is stable in three channels. Based on Newton's multi-rigid body dynamics, a two-dimensional vehicle mathematical model is formulated, which can be used to simulate the reentry vehicle helix maneuvering in the reentry flight when the moving masses are added sine and cosine command, along the y and z axes in the body frame. The influence relation between helix ballistic trajectory's maximum maneuvering radius of the moving centroid reentry vehicle and the commands with frequency and amplitude variation is established and analyzed. The simulation results indicate that the reentry vehicle has the capacity to avoid ground intercept system effectively if the moving mass unidirection shift motion is 200 mm with angular frequency 0.1 Hz or the unidirection shift motion is 100 mm with angular frequency 0.2 Hz under the condition that the mass of moving centroid mechanism is 10% of the total mass. It is the first time that the relation between helix maneuvering ballistic trajectory and the command signals is studied. The conclusions can be used to design helix maneuvering commands.