Flight Test Results Of An Adaptive Guidance System For Reusable Launch Vehicles

To enable autonomous operations in future Reusable Launch Vehicles (RLVs), reconfigurable control and adaptive guidance will often be required to facilitate recovery of the mission following a major anomalous event such as an effector failure. An adaptive guidance system that works in conjunction with a reconfigurable controller and an autonomous trajectory command reshaping algorithm is presented. The guidance law utilizes a backstepping architecture to generate pitch rate commands that drive the inner-loop control system. Under extreme failure conditions the control surfaces can saturate in an attempt to meet commanded moments. In these cases, the guidance feedback gains are reduced to preserve stability margins in the guidance loops. A case study is presented that shows the benefits of the guidance gain adaptation. Without adjusting the gains, the guidance loops go unstable, whereas stability is maintained with gain reduction.