Re-entry and terminal guidance for vertical-landing TSTO (Two-Stage To Orbit)

Abstract

There are several concepts of RLV(Reusable Launch Vehicles), which are most efficient to reduce transportation cost. We selected a VTVL(Vertical Takeoff and Vertical Landing) and TSTO(Two-Stage to Orbit) type as simulation models because such types were not investigated in the past research. The most critical problem about the vertical-landing TSTO is landing of the first stage within a limited area. This paper describes the model and a proposed new re-entry and terminal guidance for the first stage of TSTO and shows the results of total guidance simulations. The guidance includes the estimation of the remainder of downrange(range-to-go) using numerical integration of equations of motion. The accuracy of the guidance law was improved compared with a traditional drag deceleration guidance which is commonly adopted for winged re-entry vehicles. The robustness of the total guidance law was confirmed by the results of error analyses.