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Air-breathing hypersonic vehicle guidance and control studies: an integrated trajectory/control analysis methodology, phase 2
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Hattis, Philip D. Malchow, Harvey L. |
| Copyright Year | 1992 |
| Description | An integrated trajectory/control analysis algorithm has been used to generate trajectories and desired control strategies for two different hypersonic air-breathing vehicle models and orbit targets. Both models used cubic spline curve fit tabulated winged-cone accelerator vehicle representations. Near-fuel-optimal, horizontal takeoff trajectories, imposing a dynamic pressure limit of 1000 psf, were developed. The first model analysis case involved a polar orbit and included the dynamic effects of using elevons to maintain longitudinal trim. Analysis results indicated problems with the adequacy of the propulsion model and highlighted dynamic pressure/altitude instabilities when using vehicle angle of attack as a control variable. Also, the magnitude of computed elevon deflections to maintain trim suggested a need for alternative pitch moment management strategies. The second analysis case was reformulated to use vehicle pitch attitude relative to the local vertical as the control variable. A new, more realistic, air-breathing propulsion model was incorporated. Pitch trim calculations were dropped and an equatorial orbit was specified. Changes in flight characteristics due to the new propulsion model have been identified. Flight regimes demanding rapid attitude changes have been noted. Also, some issues that would affect design of closed-loop controllers were ascertained. |
| File Size | 2695637 |
| Page Count | 88 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19930003225 |
| Archival Resource Key | ark:/13960/t74v1hr7d |
| Language | English |
| Publisher Date | 1992-10-01 |
| Access Restriction | Open |
| Subject Keyword | Aircraft Stability And Control Elevons Trajectory Control Control Systems Design Single Stage To Orbit Vehicles Spacecraft Guidance Feedback Control Takeoff Hypersonic Vehicles Flight Characteristics Algorithms Spacecraft Trajectories Cubes Mathematics Spline Functions Spacecraft Control Air Breathing Engines Polynomials Trajectory Analysis Curve Fitting Spacecraft Design Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
