Commercial launch vehicle design and predictive guidance development / Matthew R. Tetlow.

Abstract

Investigates alternative reusable launch vehicle design concepts and develops a robust guidance strategy for use on the ascent and flyback phases of flight. The first concept vehicle uses air breathing engines to perform a powered return flight to the launch site; the second employs only aerodynamic forces to achieve flyback, returning unpowered. Software simulation shows that a powered return flight delivers more payload than an unpowered return flight. The guidance strategy developed is a numerical guidance system robust enough for use in real time and works by integrating the current state, along the trajectory, to the final state of the vehicle. It then compares the achieved final state to the required target state and calculates the target condition error. A parameterised non-linear optimisation technique is then used to determine the new values of the optimisation parameters required to steer the vehicle from its current position and velocity to the desired position and velocity.