Search NASA⌕ Search

SEARCH · Search NASA

Results for “landing navigation”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8

Flight performance of a navigation, guidance, and control system concept for automatic approach and landing of space shuttle orbiter

Unpowered automatic approaches and landings were conducted to study navigation, guidance, and control problems associated with terminal area approach and landing for the space shuttle vehicle. The flight tests were performed in a Convair 990 aircraft equipped with a digital flight control computer connected to the aircraft control system and displays. The tests were designed to evaluate the performance of a navigation and guidance concept that utilized blended radio/inertial navigation with VOR, DME, and ILS as the ground navigation aids. Results from 36 automatic approaches and landings from 11,300 m (37,000 ft) to touchdown are presented. Preliminary results indicate that this concept may provide sufficient accuracy to accomplish automatic landing of the shuttle orbiter without air-breathing engines.

Edwards, F. G.↗

Guidance, Navigation and Control for the Entry, Descent, and Landing of the Mars 2020 Mission

This paper presents an overview of the Guidance, Navigation and Control (GNC) system for the Entry, Descent, and Landing (EDL) phases of the Mars 2020 Mission. The EDL GNC system adds Terrain Relative Navigation to the MSL EDL GNC system1 to enable landing on landing sites with landing hazards within the landing ellipse. This paper describes the GNC architecture, including sensors, actuators and algorithms, for the entry, parachute descent, and powered flight phases of the mission.

Brugarolas, Paul↗

Terminal area automatic navigation, guidance, and control research using the Microwave Landing System (MLS). Part 2: RNAV/MLS transition problems for aircraft

The problems in navigation and guidance encountered by aircraft in the initial transition period in changing from distance measuring equipment, VORTAC, and barometric instruments to the more precise microwave landing system data type navaids in the terminal area are investigated. The effects of the resulting discontinuities on the estimates of position and velocity for both optimal (Kalman type navigation schemes) and fixed gain (complementary type) navigation filters, and the effects of the errors in cross track, track angle, and altitude on the guidance equation and control commands during the critical landing phase are discussed. A method is presented to remove the discontinuities from the navigation loop and to reconstruct an RNAV path designed to land the aircraft with minimal turns and altitude changes.

Pines, S.↗

Navigating Low-Energy Trajectories to Land on the Surface of Europa

The current interest in sending a probe to the surface of Europa in search of life demands not only efficient strategies in mission design, but also requires the capability of knowing the navigability of such types of trajectories. An initial search to find low-energy approach trajectories with a variety of topologies that are challenging to navigate is initially performed in the circular restricted three-body problem. These trajectories are subsequently converted to the ephemeris model and used for detailed navigation analysis. We explore several maneuver strategies and assess spacecraft state uncertainties at Europa arrival as well as fuel consumption.

McElrath, Tim↗

Mars Reconnaissance Orbiter Navigation Strategy for Mars Science Laboratory Entry, Descent and Landing Telecommunication Relay Support

The Mars Reconnaissance Orbiter (MRO) is an orbiting asset that performs remote sensing observations in order to characterize the surface, subsurface and atmosphere of Mars. To support upcoming NASA Mars Exploration Program Office objectives, MRO will be used as a relay communication link for the Mars Science Laboratory (MSL) mission during the MSL Entry, Descent and Landing sequence. To do so, MRO Navigation must synchronize the MRO Primary Science Orbit (PSO) with a set of target conditions requested by the MSL Navigation Team; this may be accomplished via propulsive maneuvers. This paper describes the MRO Navigation strategy for and operational performance of MSL EDL relay telecommunication support.

Mars Reconnaissance Orbiter (MRO)↗

Development of a Compact Lidar Sensor for Terrain Relative Navigation and Terrain Hazard Avoidance

A Lidar sensor utilizing linear-mode flash lidar technology and a novel Super-Resolution technique has been developed for providing Terrain Relative Navigation and Hazard Avoidance capabilities onboard landing vehicles. Processing algorithms for precision navigation and safe landing location identification take advantage of the uniform fixed pixels property of generated high resolution Digital Elevation Maps to achieve high reliability operation in near real-time. This paper describes the results of drone and helicopter flight tests of a breadboard system, explains the design and capabilities of a recently built compact prototype unit, and proposes a concepts of operation for future landing missions.

3-D Imaging↗

Development of a Compact Lidar Sensor for Terrain Relative Navigation and Terrain Hazard Avoidance

A Flash Lidar utilizing a novel Super-Resolution (SR) technique has been developed for providing Terrain Relative Navigation and Hazard Avoidance capabilities onboard landing vehicles. Processing algorithms for precision navigation and safe landing location identification take advantage of the uniform fixed pixels property of generated high resolution Digital Elevation Maps (DEMs) to achieve high reliability operation in near real-time. This paper describes the current and next generation breadboard units, report the results of recent dynamic tests, and explain the operational concept as envisioned for future landing missions.

3-D Imaging↗

Final Approach Navigation to Europa: Setting Up for a Successful Landing

Jupiter's moon Europa has been a prime target in the search for extraterrestrial life since the Galileo orbiter indicated that a saltwater ocean may exist beneath its icy crust. The proposed Europa Lander mission targets revolutionary science investigations on the surface of Europa with the main objective to search for evidence of life. Europa presents unique challenges to a landing mission because of its hostile radiation environment and the lack of information about its terrain. This paper provides an overview of Europa Lander Navigation-Deorbit, Descent, and Landing (DDL) technology development study, which is focused on the interface between ground navigation operations and onboard DDL behavior and the challenges associated with landing a probe on Europa.

McElrath, Tim↗

Architecture Options for Navigation in Cislunar Space for Human Landing System Vehicles

As part of architecture studies and insight analysis focused on requirements development into Human Landing System lunar architecture designs, multiple studies are underway to understand the sensitivities and options for achieving high precision landing on the lunar surface. The baseline approach utilizes a combination of multiple sensors to capture autonomous state observations of the lander with respect to the lunar surface. These systems are typically constrained in terms of operational altitudes by parameters such as onboard map size, camera focus, or sensor transmitted power (for altimeter observations). While these sensor suites do enable high precision landing, they are typically very complex and expensive. For a human-rated vehicle, fault detection algorithms are needed in addition to redundant sensors drive additional design complexity. Conversely, for these early missions, mass performance is key, so extended analysis is required to identify numbers of sensors, their ideal placement, and integration algorithms. A key part of this analysis is to help identify key sensor suites and options to help alleviate this design tension. An alternate approach is to take advantage and build out in-situ assets to allow for GPS-like navigation within the lunar regime through the use of navigation references or beacons. This can be achieved through the integration of navigation services into potential relays and pre-placed lunar surface assets. This research focuses on the capability of this infrastructure to support navigation in all areas of cislunar space such as: approach to the moon, in orbit around the moon, and ascent/descent operations to the surface. An augmented state linear covariance analysis (LinCov) and navigation state covariance analysis (NavCov) tools were used to assess a variety of navigation reference locations and how they can support vehicle operations through both understanding of state uncertainties and trajectory dispersions. This research helps to supplement existing studies focused on communication link analysis by providing additional insight into specific vehicle operational scenarios that are tied closely to potential Human Landing System scenarios. Key aspect of this analysis focus on the sensitivity to state knowledge of the references, the accuracy of inter-asset measurements, and placement in support of the various scenarios.

Evan J Anzalone↗

Space shuttle navigation analysis

A detailed analysis of space shuttle navigation for each of the major mission phases is presented. A covariance analysis program for prelaunch IMU calibration and alignment for the orbital flight tests (OFT) is described, and a partial error budget is presented. The ascent, orbital operations and deorbit maneuver study considered GPS-aided inertial navigation in the Phase III GPS (1984+) time frame. The entry and landing study evaluated navigation performance for the OFT baseline system. Detailed error budgets and sensitivity analyses are provided for both the ascent and entry studies.

Jones, H. L.↗

Architecture Options for Navigation in Cislunar Space for Human Landing System Vehicles

Initial vehicles destined for the moon as part of the Human Landing Systems have tight requirements in terms of autonomous precision landing. This results in complex multi-element sensor suites and complex onboard fault redundancy approach. As additional infrastructure is placed into cislunar space, these requirements for onboard systems can be relaxed by relying on system-level observations. This paper provides results of studies supporting Human Landing Risk assessments identifying sensitivities to onboard sensor performance and describes options to support the architectural using a variety of infrastructure approaches. The results are applied to lunar cruise, ascent, and descent scenarios.

Evan Anzalone↗