The Orion spacecraft will be capable of returning astronauts to a landing within 10 km of the intended landing target from low Earth orbit. The onboard entry displays will be used by the crew to monitor entry, descent, and landing. The entry displays are driven by the entry display feeder, part of the Entry Monitor System (EMS). The entry re-targeting module, also part of the EMS, provides all the data required to generate the capability footprint of the vehicle at any point in the trajectory, which is shown on the Primary Flight Display (PFD). It also recommends the safest possible re-designated landing site when the nominal landing is no longer within the capability of the vehicle, and it calculates the energy bucket, which is shown on the entry trajectory displays. These displays will allow the crew to fly like entry guidance flies throughout the entry trajectory while having the flexibility to manually steer the vehicle to best satisfy the priorities of the crew. The entry display feeder provides data from the EMS and other components of the GNC flight software to the displays at the proper rate and in the proper units. It also performs calculations that are specific to the entry displays and which are not made in any other module of the flight software. These functions and the interactions between the entry display feeder and the other components of the EMS are described, and snapshots of salient data on the entry displays are discussed.
[1]
Zachary R. Putnam,et al.
PredGuid entry guidance for Orion return from low Earth orbit
,
2010,
2010 IEEE Aerospace Conference.
[2]
Arthur E. Bryson,et al.
Applied Optimal Control
,
1969
.
[3]
George M. Siouris,et al.
Applied Optimal Control: Optimization, Estimation, and Control
,
1979,
IEEE Transactions on Systems, Man, and Cybernetics.