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At least 1,009 records · Page 56
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Incorporating AEGIS Autonomous Science into Mars Science Laboratory Rover Mission Operations

The AEGIS (Autonomous Exploration for Gathering Increased Science) intelligent targeting software system has been in use on the Mars Science Laboratory (MSL) mission since 2016. The system allows on-board autonomous selection of targets for the ChemCam remote geochemistry instrument based on analysis of images taken by the rover. This paper describes the deployment of AEGIS to MSL and the operational use of the system since rollout to science operations in May of 2016.

Deflores, Lauren↗
NASA NTRS2020

Is a Linear or a Walkabout Protocol More Efficient When Using a Rover to Choose Biologically Relevant Samples in a Small Region of Interest?

We conducted a field test at a potential Mars analog site to provide insight into planning for future robotic missions such as Mars 2020, where science operations must facilitate efficient choice of biologically relevant sampling locations. We compared two data acquisition and decision-making protocols currently used by Mars Science Laboratory: (1) a linear approach, where sites are examined as they are encountered and (2) a walkabout approach, in which the field site is first examined with remote rover instruments to gain an understanding of regional context followed by deployment of time- and power-intensive contact and sampling instruments on a smaller subset of locations. The walkabout method was advantageous in terms of both the time required to execute and a greater confidence in results and interpretations, leading to enhanced ability to tailor follow-on observations to better address key science and sampling goals. This advantage is directly linked to the walkabout method's ability to provide broad geological context earlier in the science analysis process. For Mars 2020, and specifically for small regions to be explored (e.g., <1 sq. km), we recommend that the walkabout approach be considered where possible, to provide early context and time for the science team to develop a coherent suite of hypotheses and robust ways to test them.

R. Aileen Yingst↗
NASA NTRSDate not supplied

Martian Dust Abrasion Damage on Solar Arrays: HALT Experimental Investigation and Opportunity Rover Performance Analysis

We explored the utility of ground-based highly accelerated life testing (HALT) on epitaxial lift-off (ELO) triple-junction coverglass interconnected cells (CICs) after exposure to simulated Martian dust storms. Dust storm impingement was replicated by sandblasting CICs with Mars dust simulant replicating conditions similar to the weather conditions reported by the Viking landers. We observed that even in cases when there are no observable open circuit voltage (VOC) losses, the minority carrier lifetime is reduced. Short circuit current (JSC) losses can be recovered upon cleaning, suggesting JSC losses are not linked to permanent damage, like cell cracking. This suggests a permanent degradation could be determined by quantifying the difference between recoverable and non-recoverable power loss. We mined field data from the Mars Exploration Rover, Opportunity and extracted a degradation rate to compare to our experimental data. We found exceptional agreement between 4.9 Martian years of mined field data (9.4%) and the irreversible damage observed in our HALT experiment (9.7%). We demonstrate that the laboratory method for exposing CICs to Martian dust storm conditions well represents the physical reality of long duration CIC operation on Mars.

Lyndsey McMillon-Brown↗
NASA NTRSDate not supplied

AEROKATS and ROVER Education Network (AREN) – Exploring Through Teamwork

Exploring our home planet and other venues, requires a broad range of talents and contributions. The NASA SciAct AEROKATS and ROVER Education Network (AREN) project aims to bring an array of roles and responsibilities to a project-based learning environment focused on exploring the world around us. Teamwork is critical, and activities range from artistic, fabrication, technical design, data analysis, project planning, communications, and structured field activities. The objective is to create these teams highlighting individual skills and interests combined to form unique and productive environments.

Geoffrey L Bland↗
NASA NTRS2022

Sampling of Jezero Crater Máaz Formation By Mars 2020 Perseverance Rover

Collection of samples that could be returned to Earth from the floor of Jezero crater is a major goal of the Mars 2020 mission. Laboratory analyses of these will expand exploration of Jezero, a Noachian crater on Mars characterized by a delta–lake system with high potential for habitability. The samples will also be used to test current ideas about the early planetary evolution of Mars. The Perseverance rover has collected samples from two members of the Máaz formation, mapped in orbital images as the Crater floor fractured rough unit by [1]. Type localities of the Roubion and Rochette members have been targeted and abraded prior to sample collection. Here we summarize these sampling activities and the potential of sampling the Chal member of Máaz. A similar summary for samples collected from the Séítah formation is described in Hickman-Lewis et al. (this meeting).

Mars 2020↗
NASA NTRS2021

Calibration of the SHERLOC Deep Ultraviolet Fluorescence–Raman Spectrometer on the Perseverance Rover

We describe the wavelength calibration of the spectrometer for the scanning of habitable environments with Raman and luminescence for organics and chemicals (SHERLOC) instrument onboard NASA’s Perseverance Rover. SHERLOC utilizes deep ultraviolet Raman and fluorescence (DUV R/F) spectroscopy to enable analysis of samples from the Martian surface. SHERLOC employs a 248.6 nm deep ultraviolet laser to generate Raman-scattered photons and native fluorescence emission photons from near-surface material to detect and classify chemical and mineralogical compositions. The collected photons are focused on a charge-coupled device and the data are returned to Earth for analysis. The compact DUV R/F spectrometer has a spectral range from 249.9 nm to 353.6 nm (200 cm1 to 12, 000 cm1) (with a spectral resolution of 0.296 nm (40 cm1)). The compact spectrometer uses a custom design to project a high-resolution Raman spectrum and a low-resolution fluorescence spectrum on a single charge-coupled device. The natural spectral separation enabled by deep ultraviolet excitation enables wavelength separation of the Raman/fluorescence spectra. The SHERLOC spectrometer was designed to optimize the resolution of the Raman spectral region and the wavelength range of the fluorescence region. The resulting illumination on the charge-coupled device is curved, requiring a segmented, nonlinear wavelength calibration in order to understand the mineralogy and chemistry of Martian materials.

Kyle Uckert↗
NASA NTRSDate not supplied

The first 300 sols of the SHERLOC investigation on the Mars 2020 rover

The Mars2020 mission is NASA’s latest flagship mission to Mars. The spacecraft launched in July 2020, and landed in Jezero crater on February 18, 2021 at the Octavia Butler Landing site. The rocks and sediments of Jezero crater have been argued to have preserved records of past, potentially habitable environments. The mission is characterizing the field site by analyzing chemistry, looking for organics and searching for potential biosignatures. The Scanning Habitable Environments with Ra-man and Luminescence for Organics and Chemicals (SHERLOC) is a robotic arm mounted instrument. SHERLOC combines imaging with UV resonance Raman and native deep UV fluorescence spectroscopy to identify potential biosignatures and understand the aqueous history of the Jezero Region. WATSON (Wide Angle Topographic Sensor for Operations and eNgineering), a refight of the Mars Hand Lens Imager (MAHLI) on the Curiosity rover is capable of color imaging over a wide range of resolutions (from infinity to 13.1 micron/pixel) and is used for both science and engineering. A second imager, the Autofocusing Con-textual Imager (ACI), produces gray scale images at 10.1 micron/pixel resolution at a 48 mm range.

A. E. Murphy↗
NASA NTRSDate not supplied

Exploring the Jezero Crater Floor: Overview of Results from the Mars 2020 Perseverance Rover’s First Science Campaign

The Perseverance rover embarked on its first science campaign after landing in Jezero crater on February 18, 2021 and completing ~90 days of commissioning and Ingenuity helicopter activities. During this first campaign, Perseverance explored a large swath of Jezero’s crater floor, investigating and sampling several of the topographically lowest, and potentially oldest, rocks within the crater. Crater floor units: Perseverance explored the Máaz and Séítah formations (previously mapped as the Crater Floor Fractured Rough; Cf-fr and Crater Floor Fractured 1; Cf-f-1 units[1]). These are both widespread units in the crater that potentially correlate with units outside Jezero [2-4]. The Máaz fm. was distinguished from orbit by its mafic composition and densely cratered surface, and has various hypothesized origins, including lava flows[2] and volcaniclastic airfall [3]. The Máaz fm. is important for providing age/stratigraphic constraints on the Jezero western delta. If igneous, returned Máaz fm. samples may aid in calibrating the Mars crater chronology [2,5]and understanding Mars paleomagnetism and early igneous processes(see [6]). The Séítah fm. is olivine-bearing and has been interpreted to be related to a regional unit exposed along the inner rim of Jezero crater walls and occurs more broadly in the Nili Planum and Nili Fossae region. The olivine-bearing unit and its possible correlatives has a wide range of hypothesized origins including volcaniclastic airfall, impact melt, or aeolian and fluvial deposits [2-4,7,8]. The Séítahfm.is likely the oldest unit accessible to Perseverance and represents an important part of Jezero’s pre-delta-lacustrine history. As in the Máaz fm., the lithochemistry of the samples will help studies of early Mars igneous processes. The olivine-and carbonate-bearing components of this unit may also signify habitable conditions early in Jezero’s history, samples of which would be of high geochemical and astrobiological significance, as well as for understanding the martian carbon cycle(see [9]).

Mars 2020↗
NASA NTRS2020

Mars 2020 Rover Adaptive Caching Assembly: Caching Martian Samples for Potential Earth Return

The Adaptive Caching Assembly, part of the Sampling and Caching System on the Mars 2020 Rover, consists of multiple stations that together process sample tubes containing collected Martian material, either rock cores or soil samples, and prepares hermetically-sealed sample tubes for caching on the surface of Mars. There are 7 active degrees-of-freedom, as well as a large number of passive mechanisms within the Adaptive Caching Assembly that must operate in extreme Mars conditions (i.e., temperature and pressure). Hardware cleanliness requirements significantly drove design, assembly, and test operations of the Adaptive Caching Assembly, and were found to adversely affect hardware in some cases such that late design changes and revised cleanliness operations had to be implemented. While Adaptive Caching Assembly hardware was designed to accommodate dust, testing in a representative environment is important to validate functionality is not compromised.

Silverman, Milo↗
NASA NTRS2021

Integration of an Arm Kinematics Hot Patch onboard the Curiosity Rover

NASA's Mars Science Laboratory (MSL) mission has updated the Curiosity rover's flight software multiple times since landing on Mars on August 6, 2012. The most common patching method has been a hot patch, in which running flight software is modified after being copied into RAM from its persistent storage. The latest hot patch to be installed on Curiosity fixed an issue in the robotic arm software that computes generalized inverse kinematics. Additional unit testing performed since the start of the surface mission revealed that this software can sometimes produce erroneous solutions.The cause was identified as numerical instability in a quartic root finder. When the inputs to that solver are not well conditioned, floating-point numerical issuescan cause erroneous roots to be reported. In theory, this could result in the robotic arm turret instruments being commanded to unintended positions, for example, below the terrain surface. Out of approximately 3.7 million unit test cases, 97.2\% of the position errors were below 5 mm. However, there were 16 test cases where theposition error was greater than 20 cm, and the maximum position error was 1.2 meters.The patch was uploaded to Curiosity on sol 2642 (January 11, 2020) after the solution was developed, re-implemented as a hot patch, and validated and verified using Earth-based Curiosity testbeds. A checkout test of the patch was performed on Curiosity on sol 2657, and nominal use of the patch began on sol 2658. In this paper, we describe the steps that led to integrating the arm kinematic hot patch into Curiosity's flight software, from the discovery of the bug to the nominal use of the patch in flight.

Maimone, Mark↗
NASA NTRS2021

Practical Operational Readiness Gambits: Operations Training Simulations for the Curiosity Rover

The Mars Science Laboratory team had been puttingin effort to make a Training Venue to allow for parallel shadowtactical operations for trainees to actively work alongside theprime tactical operations personnel without affecting operations,since staffing constraints and shortened operations timelineswere straining the tactical process in supporting operationstrainees in the traditional way. The COVID- 19 Pandemic presentedfurther challenges in continuing on-console training forMSL operations trainees. The MSL operations team switched tofully remote operations, thus hampering the direct mentorshipa trainee would normally receive while on site at JPL. TheMars 2020 training team had developed a concept for roveroperations training simulations based on Johnson Space Center’sextensive simulations training program for astronauts andflight controllers. The MSL team borrowed this idea, and implementedthese training simulations which are called PracticalOperational Readiness Gambits (PORGs). The PORGs so farhave focused on the Science Planner and Rover Planner roles,which are two crucial roles in tactical operations that engagein key interactions throughout a shift. PORGs are based onactual sol scenarios that have occurred on Mars and follow thetactical operations process and timeline as closely as possible.However, unlike an operations shift, PORGs can slow down orpause to allow for more mentoring time. PORGs can focus onparticular skills to test the trainees on their understanding ofa concept. PORGs increase in complexity with each scenario toease the trainees into more typical tactical operations workloads.As more trainees join the MSL operations team, more roles arebeing incorporated into PORGs. There are plans to incorporatecertified operations personnel into PORGs to practice anomalyresponse situations. PORGs have become an essential part of theMSL operations training program and will continue even afterthe return to on-site operations at JPL.

Gajeway, Jocelyn↗
NASA NTRS2021

Dynamics associated with the Corer on M2020 Perseverance Rover

This paper will report on the development of the Dynamics specifications for the Corer on Mars 2020. The corer is a critical piece of the M2020 mission, leading into the Mars Sample Return campaign. However, the configuration of the rover places it on the turret of the Robotic Arm assembly, and near to several science sensors (PIXL, SHERLOC) which are also mounted to the Turret. This paper will provide some similarities and differences to the MSL drill. Details in the development, evolution, and verification of the Dynamics specifications will be described in detail, including the hardware which had to meet these challenging specifications. In addition, the special testing venues used throughout the development & verification of M2020 (EDU corer, EM actuators, HALT testing [simulation of coring dynamics], and QMDT) will be described.

Chrystal, Kyle↗
NASA NTRS2023

An MBSE Approach for Developing an Autonomous Rover Platform

The proliferation of increasingly autonomous systems calls for new ways to address how safety is assured. As these systems become more advanced and complex, it becomes more important to model and prototype autonomous functions at the systems level and the functions that assure they are operating safely and as expected. To that effect, researchers at the National Aeronautics and Space Administration (NASA) 's Robust Software Engineering (RSE) group are working on prototyping a Research Autonomous Vehicle, commonly referred to as R-RAV. The R-RAV is an autonomous rover platform designed to act as a case study for assured autonomy research. Moreover, an overarching goal is for the R-RAV to serve as a training ground for other mission projects. In this paper, we will detail how we have used a Model-Based Systems Engineering (MBSE) approach to model a prototype of the R-RAV and test and verify its different functionalities.

MBSE↗
NASA NTRS2022

Hexagonal Prisms Form in Water-ice Clouds on Mars, Producing Halo Displays Seen by Perseverance Rover

Observations by several cameras on the Perseverance rover showed a 22° scattering halo around the Sun over several hours during northern midsummer (solar longitude 142°). Such a halo has not previously been seen beyond Earth. The halo occurred during the aphelion cloud belt season and the cloudiest time yet observed from the Perseverance site. The halo required crystalline water-ice cloud particles in the form of hexagonal columns large enough for refraction to be significant, at least 11 μm in diameter and length. From a possible 40-50 km altitude, and over the 3.3-hour duration of the halo, particles could have fallen 3-12 km, causing downward transport of water and dust. Halo-forming clouds are likely rare due to the high supersaturation of water that is required but may be more common in northern subtropical regions during northern midsummer.

M.T. Lemmon↗
NASA NTRSDate not supplied

Effects of Mars Analogue Dust Deposition on DUV Raman Spectra: Implications for the Mars2020 Perserverance Rover SHERLOC Instrument

The Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC) instrument suite includes a deep ultraviolet (DUV) Raman and fluorescence instrument on the robotic arm of the Mars2020 (M2020) Perseverance rover [1]. When sufficiently thick dust coatings are present, substrate surfaces are not detected, and mineralogical information not obtained. For example, the effect of palagonitic dust coatings as a function of depth to various substrates on thermal emission, VNIR, and Mössbauer spectra are reported by [2, 3]. In this study, we use the same palagonitic dust to study the effect of dust coating thickness on DUV Raman spectra.

N. C. Haney↗
NASA NTRS2022

Mars 2020 Perseverance Rover Studies of the Martian Atmosphere Over Jezero From Pressure Measurements

The pressure sensors on Mars rover Perseverance measure the pressure field in the Jezero crater on regular hourly basis starting in sol 15 after landing. The present study extends up to sol 460 encompassing the range of solar longitudes from Ls ∼ 13°–241° (Martian Year (MY) 36). The data show the changing daily pressure cycle, the sol-to-sol seasonal evolution of the mean pressure field driven by the CO2 sublimation and deposition cycle at the poles, the characterization of up to six components of the atmospheric tides and their relationship to dust content in the atmosphere. They also show the presence of wave disturbances with periods 2–5 sols, exploring their baroclinic nature, short period oscillations (mainly at night-time) in the range 8–24 min that we interpret as internal gravity waves, transient pressure drops with duration ∼1–150 s produced by vortices, and rapid turbulent fluctuations. We also analyze the effects on pressure measurements produced by a regional dust storm over Jezero at Ls ∼ 155°.

A. Sánchez-Lavega↗
NASA NTRS2022

The Curiosity Rover’s Exploration of Glen Torridon, Gale Crater, Mars: An Overview of the Campaign and Scientific Results

The Mars Science Laboratory rover, Curiosity, explored the clay mineral-bearing Glen Torridon region for 1 Martian year between January 2019 and January 2021, including a short campaign onto the Greenheugh pediment. The Glen Torridon campaign sought to characterize the geology of the area, seek evidence of habitable environments, and document the onset of a potentially global climatic transition during the Hesperian era. Curiosity roved 5 km in total throughout Glen Torridon, from the Vera Rubin ridge to the northern margin of the Greenheugh pediment. Curiosity acquired samples from 11 drill holes during this campaign and conducted the first Martian thermochemolytic-based organics detection experiment with the Sample Analysis at Mars instrument suite. The lowest elevations within Glen Torridon represent a continuation of lacustrine Murray formation deposits, but overlying widespread cross bedded sandstones indicate an interval of more energetic fluvial environments and prompted the definition of a new stratigraphic formation in the Mount Sharp group called the Carolyn Shoemaker formation. Glen Torridon hosts abundant phyllosilicates yet remains compositionally and mineralogically comparable to the rest of the Mount Sharp group. Glen Torridon samples have a great diversity and abundance of sulfur-bearing organic molecules, which are consistent with the presence of ancient refractory organic matter. The Glen Torridon region experienced heterogeneous diagenesis, with the most striking alteration occurring just below the Siccar Point unconformity at the Greenheugh pediment. Results from the pediment campaign show that the capping sandstone formed within the Stimson Hesperian aeolian sand sea that experienced seasonal variations in wind direction.

Kristen A Bennett↗