Two-Dimensional Trajectory Optimization for Soft Lunar Landing Considering a Landing Site

  • Park, Bong-Gyun (Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology) ;
  • Ahn, Jong-Sun (Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology) ;
  • Tahk, Min-Jea (Department of Aerospace Engineering, Korea Advanced Institute of Science and Technology)
  • Received : 2010.03.27
  • Accepted : 2011.09.16
  • Published : 2011.09.30


This paper addresses minimum-fuel, two-dimensional trajectory optimization for a soft lunar landing from a parking orbit to a desired landing site. The landing site is usually not considered when performing trajectory optimization so that the landing problem can be handled. However, for precise trajectories for landing at a desired site to be designed, the landing site has to be considered as the terminal constraint. To convert the trajectory optimization problem into a parameter optimization problem, a pseudospectral method was used, and C code for feasible sequential quadratic programming was used as a numerical solver. To check the reliability of the results obtained, a feasibility check was performed.


Supported by : Korea Science and Engineering Foundation


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