SITUATION: Leidos Inc was performing work for the Air Force who was interested in maturing the technical readiness of a hypersonic weapon to meet the threat posed from overseas. Though hypersonic technology had been around for several decades its use in a weapon was unknown and much uncertainty lay in its use. There were two types of vehicles being considering: a boost then glide vehicle and a scramjet powered vehicle.
TASK: Develop guidance algorithms that demonstrated the capability of the vehicle to meet mission objectives with in certain contraints and boundaries.
ACTION: Guidance system requirements were gathered and consolidated and if they were not available they were generated. Requirements consisted of midcourse and terminal phases of flight, timeline and schedule of events and end game constraints such as terminal flight path angle and vehicle speed. Guidance system models were developed and research was performed on which guidance laws could best meet objects. Mathematical models were constructed and implemented into government furnished 6-DOF simulations.
RESULT: Using a state-dependent Ricatti equation (SDRE) approach was found to be advantageous to provide for shaping of the trajectory to meet mission requirements. Additionally a Kappa trajectory shaping guidance law was also implemented for comparison purposes which required less tuning and was more robust to providing an acceptable solution. Monte Carlo simulations showed that ground targets were able to be engaged within a specified circular error of probability (CEP).