The Morpheus prototype lander is a vertical testbed developed by NASA Johnson Space Center to assess advanced technologies. Between December 2013 and May 2014, Morpheus completed a series of flight tests at Kennedy Space Center (KSC) to demonstrate autonomous landing and hazard avoidance for future exploration missions. The vehicle is fueled with liquid oxygen and liquid methane, a clean and non-toxic propellant. As a prototype vehicle being tested in Earth's atmosphere, Morpheus requires a robust roll control system (RCS) to counteract aerodynamic forces. This paper describes the control algorithm designed that requests firing and delay times based on roll orientation. Design, analysis, and testing are supported using a high-fidelity simulation of vehicle dynamics. This paper also details the wind profiles generated using historical wind data, which are necessary to validate the RCS in the simulation environment. In preparation for Morpheus testing, the wind model was expanded to create day-of-flight (DOF) wind profiles based on data delivered by the KSC meteorology group.The Morpheus RCS consists of four thrusters fueled by the main engine propulsion tanks. Two thrusters in both the positive and negative roll direction maintain vehicle pointing during flight. The thrusters are oriented on the vehicle as shown in Figure 1. +Roll +Roll -Roll -Roll

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Spacecraft control algorithms must know the expected spacecraft response to any command to the available control effectors, such as reaction thrusters or torque devices. Spacecraft control system design approaches have traditionally relied on the estimated vehicle mass properties to determine the desired force and moment, as well as knowledge of the effector performance to efficiently control the spacecraft. A pattern recognition approach can be used to investigate the relationship between the control effector commands and the spacecraft responses. Instead of supplying the approximated vehicle properties and the effector performance characteristics, a database of information relating the effector commands and the desired vehicle response can be used for closed-loop control. A Monte Carlo simulation data set of the spacecraft dynamic response to effector commands can be analyzed to establish the influence a command has on the behavior of the spacecraft. A tool developed at NASA Johnson Space Center (Ref. 1) to analyze flight dynamics Monte Carlo data sets through pattern recognition methods can be used to perform this analysis. Once a comprehensive data set relating spacecraft responses with commands is established, it can be used in place of traditional control laws and gains set. This pattern recognition approach can be compared with traditional control algorithms to determine the potential benefits and uses.