Techniques for developing approximate optimal advanced launch system guidanceAn extension to the authors' previous technique used to develop a real-time guidance scheme for the Advanced Launch System is presented. The approach is to construct an optimal guidance law based upon an asymptotic expansion associated with small physical parameters, epsilon. The trajectory of a rocket modeled as a point mass is considered with the flight restricted to an equatorial plane while reaching an orbital altitude at orbital injection speeds. The dynamics of this problem can be separated into primary effects due to thrust and gravitational forces, and perturbation effects which include the aerodynamic forces and the remaining inertial forces. An analytic solution to the reduced-order problem represented by the primary dynamics is possible. The Hamilton-Jacobi-Bellman or dynamic programming equation is expanded in an asymptotic series where the zeroth-order term (epsilon = 0) can be obtained in closed form.
Document ID
19920046676
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Feeley, Timothy S. (NASA Langley Research Center Hampton, VA, United States)
Speyer, Jason L. (California, University Los Angeles, United States)