Integral performance optimization for the two-stage-to-orbit RBCC-RKT launch vehicle based on GPM

Abstract

The takeoff-mass of a two-stage-to-orbit Rocket-Based Combined Cycle Engine-Rocket (RBCC-RKT) launch vehicle is a crucial factor in its comprehensive performance. This paper optimizes the takeoff-mass together with the trajectory by reformulating it to a nonlinear optimal control problem. The range of the second stage rocket mass is considered as a process constraint. When the scopes of initial and terminal states are specified, the problem can be solved by using the Gauss pseudo-spectral method (GPM). In order to reduce the convergent difficulty caused by using table data, the data in different stages are utilized by employing an integrated interpolation strategy through the optimization. Simulation results show that the mass can be effectively optimized to meet the inertia mass ratio constraint of the first-stage, and the separation of Mach number and altitude can be optimized at the same time.

Time-varying Formation Dynamics Modeling and Constrained Trajectory Optimization of Multi-quadrotor UAVs

“…( 16), process constraints Eqs. (18)(19)(20)(21), ( 23), ( 24), (29). Now, the problem we faced are:…”

“…At present, Gauss pseudospectral method (GPM) has many applications in trajectory optimization. To optimize the takeoff-mass for a two-stage-to-orbit RBCC-RKT launch vehicle, which is a crucial factor of integral performance, Zhang et al [18] combined it with the trajectory optimization simultaneously by treating them as a nonlinear control problem, when the scopes of initial and terminal qualities as well as speeds are specified, the problem is solved by using the Gauss pseudospectral method. In literature [19], in order to optimize the trajectory of a general supersonic vehicle driven by a hydrocarbon fueled ramjet in the ascent phase, an optimization method based on GPM was proposed based on the characteristics of the propulsion system.…”