PREDICTOR-CORRECTOR GUIDANCE ALGORITHM FOR USE IN HIGH-ENERGY AEROBRAKING SYSTEM STUDIES

A three-degree-of-freedom predictor-corrector guidance algorithm is developed specifically for use in high energy aerobraking performance evaluations. This paper presents both the development and capabilities of this guidance algorithm as applied to the design of manned Mars aerobraking vehicles. Atmospheric simulations are performed to demonstrate the applicability of this algorithm and to evaluate the effects of off-nominal conditions upon the mission. The off-nominal conditions simulated result from atmospheric density and aerodynamic characteristic mispredictions. The guidance algorithm also provides relief from the high deceleration levels typically encountered in a high-energy aerobraking mission profile. Through this analysis, bank-angle modulation is shown to be an effective means of providing deceleration relief. Furthermore, the capability of the guidance algorithm to manage off-nominal vehicle aerodynamic and atmospheric density variations is demonstrated.