New methodologies for onboard generation of Terminal Area Energy Management trajectories for autonomous reusable launch vehicles

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2001.Includes bibliographical references (p. 144-145).Onboard trajectory generation capability greatly increases an autonomous reusable launch vehicle's capacity for recovering from unexpected disturbances or anomalous conditions. Such capability dispenses with the routine of pre-defined, mission specific trajectories and contingencies, which has been in use since the early days of the Shuttle. Newer guidance techniques, employing modem computing power and faster algorithms, can therefore provide savings in both operational cost and design time, while enhancing both mission robustness and efficiency. Weaknesses in the current Terminal Area Energy Management phase guidance scheme are identified and shown to be remedied with an onboard trajectory generator. Subsequently, new methodologies are presented as well as an approach to attaining onboard trajectory generation capability using the NASA/Orbital X-34 gliding reentry vehicle as the representative testbed model. The approach utilizes the full nonlinear equations of motion to rapidly generate 3- degrees-of-freedom descent trajectories for a low lift over drag, gliding reusable launch vehicle from any portion of the Terminal Area Energy Management flight regime to the AutoLanding Interface. Full coupling of the longitudinal and lateral aspects, as well as actual vehicle dynamic capabilities and constraints, will result in guidance outputs that are both realistic and flyable. Key technology components are identified and preliminary results and comparisons are presented.by Andrew C. Grubler.S.M

Space Transportation Materials and Structures Technology Workshop

The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems

Paper Session I-A - Creating Space Mobility: A Vision for Our Twenty-first Century Spacelift Architecture

The current national spacelift architecture remains largely unchanged from the 60’s, consisting mainly of expendable boosters, a small number of operating ranges populated with vehicle specific launch complexes, and ground-based tracking, telemetry and command (lT&C) -- one more akin to the experimental than the operational world. Today, however, we stand at a turning point in space-related technologies that will enable a whole new\u3c class of systems promising to dramatically lower the cost of space access, while increasing operability, responsiveness and reliability to levels approaching those of air and sealift. The key components of this future architecture -- an Evolved Expendable Launch Vehicle (EELV); Single-Stage-to-Orbit (SSTO) Reusable Launch Vehicles (RLV); an Orbital Transfer Vehicle; and a Space Based Range -- will offer synergistic benefits over our current architecture that finally lead to the true aircraft-like access envisioned since before Sputnik. Only when such a system is in place, either nationally or internationally, can we truly consider ourselves to be spacefaring, fully exploiting the opportunities that occupying the high ground entails. This paper outlines this future vision for a fully functional space architecture, reviewing the current state of development and key technologies necessary to field the key components. It will outline how their operational interaction maximizes spacelift capability for minimum cost, thus expanding the space transportation market and providing new capabilities for the civil, commercial and military sectors. The resulting document serves as an important concept of operations definition, usable by planning, RD&A and operations communities during this period of transition

SSTAC/ARTS review of the draft Integrated Technology Plan (ITP). Volume 6: Controls and guidance

Viewgraphs of briefings from the Space Systems and Technology Advisory Committee (SSTAC)/ARTS review of the draft Integrated Technology Plan (ITP) on controls and guidance are included. Topics covered include: strategic avionics technology planning and bridging programs; avionics technology plan; vehicle health management; spacecraft guidance research; autonomous rendezvous and docking; autonomous landing; computational control; fiberoptic rotation sensors; precision instrument and telescope pointing; microsensors and microinstruments; micro guidance and control initiative; and earth-orbiting platforms controls-structures interaction

2006 NASA Range Safety Annual Report

Throughout 2006, Range Safety was involved in a number of exciting and challenging activities and events, from developing, implementing, and supporting Range Safety policies and procedures-such as the Space Shuttle Launch and Landing Plans, the Range Safety Variance Process, and the Expendable Launch Vehicle Safety Program procedures-to evaluating new technologies. Range Safety training development is almost complete with the last course scheduled to go on line in mid-2007. Range Safety representatives took part in a number of panels and councils, including the newly formed Launch Constellation Range Safety Panel, the Range Commanders Council and its subgroups, the Space Shuttle Range Safety Panel, and the unmanned aircraft systems working group. Space based range safety demonstration and certification (formerly STARS) and the autonomous flight safety system were successfully tested. The enhanced flight termination system will be tested in early 2007 and the joint advanced range safety system mission analysis software tool is nearing operational status. New technologies being evaluated included a processor for real-time compensation in long range imaging, automated range surveillance using radio interferometry, and a space based range command and telemetry processor. Next year holds great promise as we continue ensuring safety while pursuing our quest beyond the Moon to Mars

Project Morpheus: Morpheus 1.5A Lander Failure Investigation Results

On August 9, 2012 the Morpheus 1.5A vehicle crashed shortly after lift off from the Kennedy Space Center. The loss was limited to the vehicle itself which was pre-declared to be a test failure and not a mishap. The Morpheus project is demonstrating advanced technologies for in space and planetary surface vehicles including: autonomous flight control, landing site hazard identification and safe site selection, relative surface and hazard navigation, precision landing, modular reusable flight software, and high performance, non-toxic, cryogenic liquid Oxygen and liquid Methane integrated main engine and attitude control propulsion system. A comprehensive failure investigation isolated the fault to the Inertial Measurement Unit (IMU) data path to the flight computer. Several improvements have been identified and implemented for the 1.5B and 1.5C vehicles

Dynamic Inversion and Backstepping Controller Robustness Analysis for a Reusable Launch Vehicle

The Air Force has been working towards developing technology for operationally responsive space (ORS), which is the ability to launch military assets into space without the long set up time currently required. Part of the solution to ORS is to develop a reusable booster vehicle capable of sending any vehicle into orbit, then descending back to the atmosphere and landing unpowered so that it may take another vehicle into orbit with a 48 hour turnaround time. Currently classical gain tuning techniques are used to design a controller for a specific mission, which may hinder the vehicle’s ability to perform multiple missions if gains have to be re-tuned. Advanced nonlinear control methods like dynamic inversion and backstepping may eliminate the need to use classical gain tuning techniques that may increase quick turnaround time, reliability, and performance. Both methods consider the dynamics of the vehicle allowing the controller to be applied to the whole flight envelope. However, they are model-based methods that require knowledge of plant aerodynamics. The objective was to develop a backstepping outer loop and dynamic inversion inner loop controller for a reusable launch vehicle configuration and evaluate its robustness characteristics by inserting aerodynamic uncertainties into the static and control surface aerodynamic data separately and together. Both dynamic inversion and backstepping were susceptible to control surface aerodynamic uncertainties more than static aerodynamics. The benefit of using dynamic inversion and backstepping was that it was formulated so that it decouples the system of equations as long as the dynamics were modeled accurately. The control variable became a bank of decoupled integrators. However, when uncertainties were introduced into the plant model, the controller was unable to accurately model the dynamics, which re-introduced axes coupling inherent in the plant. The coupling caused performance in one axis to degrade if another axis degraded

Systems integration and demonstration of advanced reusable structure for ALS

The objective was to investigate the potential of advanced material to achieve life cycle cost (LCC) benefits for reusable structure on the advanced launch system. Three structural elements were investigated - all components of an Advanced Launch System reusable propulsion/avionics module. Leading aeroshell configurations included sandwich structure using titanium, graphite/polyimide (Gr/PI), or high-temperature aluminum (HTA) face sheets. Thrust structure truss concepts used titanium, graphite/epoxy, or silicon carbide/aluminum struts. Leading aft bulkhead concepts employed graphite epoxy and aluminum. The technical effort focused on the aeroshell because the greatest benefits were expected there. Thermal analyses show the structural temperature profiles during operation. Finite element analyses show stresses during splash-down. Weight statements and manufacturing cost estimates were prepared for calculation of LCC for each design. The Gr/PI aeroshell showed the lowest potential LCC, but the HTA aeroshell was judged to be lower risk. A technology development plan was prepared to validate the applicable structural technology