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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.

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At least 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

Explorations of Quantum-Classical Approaches to Scheduling a Mars Lander Activity Problem

An effective approach to solving problems involving mixed (continuous and discrete) variables and constraints, such as hybrid systems, is to decompose them into subproblems and integrate dedicated solvers geared toward those subproblems. Here, we introduce a new framework based on a tree search algorithm to solve hybrid discrete-continuous problems that incorporates: (1) a quantum annealer that samples from the configuration space for the discrete portion and provides information about the quality of the samples, and (2) a classical computer that makes use of information from the quantum annealer to prune and focus the search as well as check a continuous constraint. We consider four variants of our algorithm, each with progressively more guidance from the results provided by the quantum annealer. We empirically test our algorithm and compare the variants on a simplified Mars Lander task scheduling problem. Variants with more guidance from the quantum annealer have better performance.

scheduling↗
NASA NTRS2019

Long-Duration Venus Lander Development

One of the most intriguing planets in our solar system for both solar system and extra-solar system science is Venus. Venus is the planet most similar to Earth in several key ways and many believe Venus-like planets are more common around other suns than are Earth-like planets. Therefore scientific understanding of our sister planet is a high priority. However, the hostile environmental conditions at the surface coupled with thick acid clouds and dense atmosphere have made understanding this planet very challenging. Remote sensing of surface features and near surface environments is very limited. The hostile environment has also limited the ability of landers to survive, in fact the longest living asset survived just over two hours. Even after over 50 years of attempts to explore Venus, many key measurements, especially near the surface, are still in the future. NASA has begun to undertake steps to overcome the technical challenges and is developing the capability for sustained operations and science return from this important body. For example, recent technology advances in high temperature sensors, electronics, power, and other systems have been funded and this, combined with the new capabilities to replicate Venus conditions on Earth, are changing the outlook for Venus surface exploration.

Kremic, Tibor↗
NASA NTRS2019

Defining Navigation Requirements for Future Precision Lander Missions

Human mission concepts for both the Moon and Mars require landing precision capabilities beyond the current state of art. The Safe and Precise Landing Integrated Capabilities Evolution (SPLICE) project leverages previous work at NASA to develop multimission precision landing and hazard avoidance (PL&HA) technologies to meet the advanced landing requirements. SPLICE aims to develop guidance, navigation and control (GN&C) capabilities for both Moon and Mars lander missions. The approach the project is using to identify a standard suite begins with developing a PL&HA requirements matrix to inform technology investments. The approach to develop a multi-mission navigation requirements matrix includes identifying representative concepts of operations for both robotic and human missions. It also identifies navigation sensor options with estimated performance parameters. This paper summarizes the concepts of operations and sensors considered to develop the SPLICE PL&HA requirements matrix. A description of the analysis used to determine candidate optimal sensor suites and initial results are provided.

Dwyer Cianciolo, Alicia↗
NASA NTRSDate not supplied

How the Allocation of Lander Functions Impacts Human Lunar Exploration Architecture Propellant Demands

As NASA looks to the moon as a proving ground for the technologies required to conduct the first human exploration campaign of Mars, this study assesses the potential propellant demands that a sustained human lunar presence would require. In particular, this study evaluates how the allocation and distribution of vehicle functions to a different number of vehicles can impact the propellant required to conduct a human lunar exploration mission. Four different transportation architectures for human lunar exploration and three different refueling assumptions were defined. The impact on the propellant required for a mission was assessed for all architectures and refueling assumptions for ranges of crew payload mass, vehicle inert mass fraction, and a sensitivity to the mission maneuver velocity magnitudes. The results of this analysis show that aggregating vehicle functions to a single-stage lander vehicle can have a positive impact on the architecture's level of vehicle reusability and that an increase in the number of refueling opportunities reduces the mass of the vehicles and of the propellant required per mission.

Matteo A. Clark↗
NASA NTRS2021

The Mercury Lander Mission Concept Study: Enabling Transformative Science from the Surface of the Inner-Most Planet

As an end-member of rockyplanet formation, Mercury holds unique clues about the original distribution of elements in the earliest stages of Solar System development,as well as how planets form and evolve in close proximity to their host starsgenerally. This Mercury Lander mission concept enables in situ surface measurements that address several fundamental science questions raised by MESSENGER’s pioneering exploration of Mercury. Such measurements are needed to understand Mercury’s unique mineralogy and geo-chemistry; to characterize the structure of the planet’s proportionally massive core’s structure; to measure the planet’s active and ancient magnetic fields at the surface; to investigate the processes that alter the surface and produce the exosphere; and to provide groundtruth for current and future remote datasets

C M Ernst↗
NASA NTRS2000

Internet Based Operations for the Mars Polar Lander Mission

The Mars Polar Lander (MPL) mission is the first planetary mission to use Internet-based distributed ground operations where scientists and engineers collaborate in daily mission operations from multiple geographically distributed locations via the Internet.

Mission↗
NASA NTRS2019

Maneuver design overview of the 2018 InSight Mars lander mission

Launched on May 5, 2018, the Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport (InSight) spacecraft landed safely on Mars on November 26, 2018. To deliver the lander accurately to the landing site, six trajectory correction maneuvers (TCMs) were planned along the reference trajectory from Earth launch to Mars entry. For the last two TCMs, there were two corresponding contingency TCMs planned that could be executed in the event that the corresponding nominal one failed. There were also twenty pre-designed menu TCMs available for execution at the time of the last contingency TCM, about 8 hours before the Mars entry, descent, and landing. This navigation paper overviews the maneuver design of each TCM, as well as how each one actually performed during operations.

Wallace, Mark↗
NASA NTRS2019

Orbiters, CubeSats, and radio telescopes, oh my; entry, descent, and landing communications for the 2018 InSight Mars lander mission

The Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport (InSight) Mars lander mission was launched on May 5th, 2018 and its November 26, 2018 entry, descent, and landing sequence was observed by no less than five separate assets. The Mars Reconnaissance Orbiter (MRO) in orbit about Mars, the two Mars Cube One (MarCO) probes flying by, and two radio telescopes back on Earth were all used for this critical event communication coverage. These many paths of communication were enabled via the InSight launch/arrival strategy design, MRO orbital phasing selection, and MarCO trajectory design

Wagner, Sean↗
NASA NTRS2020

The Mars 2020 lander vision system field test

The Mars 2020 Lander Vision System estimates position relative to a map and provides this information to the spacecraft so that large hazards can be avoided during landing. The LVS is a new mission critical sensor and as such requires extensive validation. A field test conducted in May 2019 was the primary means to prove that the LVS will operate as designed. During this test over 600 independent real-time runs on engineering model LVS hardware and software were executed and clearly showed that it could meet a 40m position estimation requirement over a wide operational envelope. This paper will describe the test approach, operations and results. Specific examples as well as aggregate performance will be discussed along with off-nominal testing and fault recovery.

Montgomery, J.↗
NASA NTRS2017

Mars Reconnaissance Orbiter Navigation Strategy for the ExoMars Schiaparelli EDM Lander Mission

The Mars Reconnaissance Orbiter (MRO) had planned to provide surface relay support for the brief mission of the ExoMars Schiaparelli EDM lander on Mars in October 2016. Launched with the Trace Gas Orbiter (TGO) in March 2016, Schiaparelli and TGO composed the first part of the ExoMars program. To place MRO directly overhead on its third overflight of the Schiaparelli landing site, two propulsive maneuvers were performed starting three months prior to Shiaparelli’s arrival at Mars. This paper documents the maneuver strategy employed by the MRO Navigation Team to support the Schiaparelli overflight campaign.

Schulze, William B.↗
NASA NTRS2018

Propulsion System Options for a Potential Sample Return Lander (SRL) for Mars

A potential Mars Sample Return (MSR) campaign would be very unique challenge and has been the focus of technology development and planning efforts at JPL for several decades. The latest mission concept study focuses on a potential Sample Return Lander (SRL). The potential SRL examined several propulsion system approaches using monopropellant and bi-propellants for the terminal descent phase. A ranking was developed based on a mathematical optimization program. This paper focuses on the evaluations conducted for these system options. Historically, monopropellant and bi-propellant propulsion systems are usually considered for this application; this study took a fresh look at both conventional State of the Art (SOA) pressure fed monopropellant and bi-propellant propulsion system and augmenting the system using small Electrically Driven Pumps (EDP) for both these propulsion systems.

Preudhomme, Michael↗
NASA NTRS2019

Global search of resonant trasfers for a Europa Lander to Clipper data relay

Following its prime mission Europa Clipper becomes a potential asset to relay data from a proposed Europa Lander back to Earth. To this end, we describe an efficient method to globally search for trajectories that repeatedly fly over the same location of Europa. Different families of trajectories emerge with different flyby geometries that satisfy a convoluted set of landing constraints. Here, the landing location and local solar time must match a limited set derived from expected Clipper observations, while providing multiple opportunities to land in a given season. We include estimates for data volume and radiation dose associated with these resonant trajectories.

Campagnola, Stefano↗
NASA NTRS2019

All-metal dual frequency RHCP high gain antenna for the extreme environments of a potential Europa Lander

A new all-metal dual-frequency RHCP high gain antenna is under development at NASA’s Jet Propulsion Laboratory for a potential Europa Lander. The antenna is mainly made of metal so it could survive the harsh environment conditions of Europa (i.e. very low temperature and high radiation and ESD levels). The antenna is flat to meet drastic volume constraints and has efficiencies higher than 80% at both the uplink and downlink X-band Deep Space frequency bands. This antenna is a key component for the potential mission enabling Direct Link to Earth (DTE) without any relying on an Orbiter to relay the data.

Chahat, Nacer↗
NASA NTRS2020

The Dual-Rasp Sampling System for an Enceladus Lander

The Dual-Rasp sampling system has been developed for the unique sampling environment of a lander mission to the surface of Saturn’s moon Enceladus. Plume material from the subsurface ocean that has fallen to the surface is desired resulting in an objective to sample the topmost layer of icy material. The low gravity and potential large range of surface properties are challenges for the sampling system. The Dual-Rasp sampling system has two counter-rotating rasp cutters with teeth that remove material that is thrown up between the cutters. Two prototypes of the Dual-Rasp sampling system were built and tested, one with a carousel and one that uses pneumatics for sample transfer.

Ubellacker, Samuel↗
NASA NTRSDate not supplied

Integrated Precision Landing Performance and Technology Assessments of a Human-Scale Mars Lander Using a Generalized Simulation Framework

Human-scale missions to Mars will likely require multiple landers delivered precisely to designated locations. The current NASA human Mars reference architecture assumes delivery of three 25 t payloads from a 1- or 5-Sol orbit to the surface with a landing precision of 50 m to ensure logistics are located near the habitat. While initial navigation estimates improve with on-orbit ground tracking, errors increase during post-deorbit coast. Likewise, Mars atmospheric variability and forecasting uncertainty means that the entry vehicle guidance, navigation, and control systems must be robust to accommodate landing during any time of day or Mars year, including during dust storms. Precision landing technologies are currently being assessed to determine if onboard navigation sensors are sufficient to enable the landing accuracy required or if additional navigation aids such as surface or orbiting beacons will be needed. This study evaluates the system performance requirements to meet the desired landing accuracy for the reference vehicle design and entry, descent, and landing concept of operations. A detailed six degree-of-freedom integrated performance simulation framework is used to perform the assessment and demonstrate that under current assumptions, onboard navigation sensors are sufficient to support precision landing.

spacecraft navigation↗
NASA NTRS2020

The Dual-Rasp Sampling System for an Enceladus Lander

The Dual-Rasp sampling system has been developed for the unique sampling environment of a lander mission to the surface of Saturn’s moon Enceladus. Plume material from the subsurface ocean that has fallen to the surface is desired resulting in an objective to sample the topmost layer of icy material. The low gravity and potential large range of surface properties are challenges for the sampling system. The Dual-Rasp sampling system has two counter-rotating rasp cutters with teeth that remove material that is thrown up between the cutters. Two prototypes of the Dual-Rasp sampling system were built and tested, one with a carousel and one that uses pneumatics for sample transfer.

Backes, Paul↗