Supervisor:
Southwest Ordnance Industry Bureau
Organizer:
Chongqing Ordnance Industry Society
Chongqing University of Technology
Chongqing University of Technology
Research on rocket landing phase guidance based on improved convex optimization method
| DOI: | 10.11809/bqzbgcxb2024.04.004 |
| Keywords: | reusable launch vehicle; thrust adjustment; convex optimization; polynomial guidance; switching strategy |
| Abstract: | The ideal state for rocket vertical landing is to maintain thrust close to the gravitational force during the descent and equal to the gravitational force at the moment of landing. Currently, the widely used convex optimization guidance method generates a thrust adjustment curve in the form of Bang Bang, where the engine adjusts the thrust between maximum and minimum values according to the current and target states. The use of convex optimization guidance results in excessive acceleration during the rocket’s descent, and its stability cannot be guaranteed. Therefore, this paper proposes an improved convex optimization based rocket landing guidance law. With fuel optimization as the goal, a trajectory planning method based on convex optimization guidance is used to generate the initial trajectory. Suitable discrete points are selected on the initial planned control curve, and the slope value of the control quantity based on convex optimization guidance between two adjacent discrete points is calculated. The calculated point of sudden increase in slope is taken as the algorithm switching point, and the guidance law based on the fourth order polynomial is switched when the rocket adjusts the thrust value to reach the point of sudden increase until landing. Simulation results show that compared with the existing single guidance method, the proposed method solves the problem of excessive deceleration in the traditional convex optimization method and minimizes fuel consumption to the greatest extent. |
| Published: | 2024-04-30 |