On-line approach/landing trajectory generation with input deviation bound uncertainty for reusable launch vehicles

2008 IEEE International Conference on Control Applications

2008

When a reusable launch vehicle (RLV) experiences a failure, it is crucial to recover the vehicle from such failure in real time. Our previous works proposed a scheme of motion primitives (MPs) and neighboring optimal control (NOC) to deal with on-line trajectory reshaping on approach and landing (A&L). Furthermore, a robustifying term was introduced to robustify NOC when the failures are severe. Wind speed especially wind shear has been shown to be a greater hazard than had been appreciated, however, the flight safety during A&L has to be treated more seriously when wind effect is included. In this paper, wind effects on robust A&L trajectory generation for RLVs are discussed based on our prior works, namely, neighboring feasible trajectory existence theorem (NFTET) and trajectory robustness theorem (TRT). A straightforward wind effect theorem (WET) will then be investigated. According to WET, the modifications to the NOC approach and robustification can on-line recover those vehicles in winds from some failures even if they are severe. The simulation results verified the conclusions.

Robust approach and landing trajectory generation for reusable launch vehicles in winds

2008 IEEE International Conference on Control Applications

2008

Disturbance Rejection in Approach and Landing Trajectory Generation for RLVs

2008 IEEE National Aerospace and Electronics Conference

2008

Safety, reliability and operational costs play important roles plane of symmetry is then defined by the following point mass in reusable launch vehicle (RLV) program. Our previous works proposed equations [2]-[5] a scheme of motion primitives and neighboring optimal control to deal with on-board failure recovery for a RLV. In this paper, disturbance D( -siny)g(1) rejection for system parameters and winds is discussed. Robustification W is mostly needed. l -CosTh) 9(2)

Extension of motion primitives and neighboring optimal control used in trajectory generation for RLVs

Proceedings of the IEEE 2009 National Aerospace &Amp; Electronics Conference (NAECON)

2009

In recent years, the Department of Defense and NASA have imposed significant resources on developing advanced launch technologies. Reusable launch vehicle (RLV) program is one of such efforts to take the place of space shuttles for RLVs. Our previous research proposed a scheme of motion primitives (MPs) and neighboring optimal control (NOC) to deal with online failure recovery for an RLV during approach and landing (A&L). In this paper, more general system dynamics is employed and the extension of MPs and NOC used in the trajectory generation during both terminal area energy management (TAEM) and A&L is discussed.