Robust Flight Control Law Design for Automatic Landing Flight Experiment

Abstract Automatic Landing FLight EXperiment, ALFLEX, is conducted by National Aerospace Laboratory (NAL) and National Space Development Agency of Japan (NASDA) in order to develop the automatic landing technology for future unmanned reentry space vehicle, HOPE(H- II Orbiting PlanE). Total of 13 flight experiments were conducted at Woomera Australia in 1996, and all flight experiments were perfectly completed. Because ALFLEX vehicle, which is dynamically similar sub-scaled model(37%) of HOPE, is the unmanned and autonomous vehicle which has tip-fin wings, the flight control law has to achieve high-response-performance and robustness simultaneously. In this paper, the design method, which connects the MDM/MDP(Multiple Delay Model/Multiple Design Point) and the H∞ control design method combined with Exact Model Matching to achieve the objectives, is presented. And the results of flight experiment about the performance and the robustness are also presented.