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Studying Passive Dust Mitigation on Anisotropic Structured Surface
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By NASA
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Regolith Adherence Characterization, or RAC, is one of 10 science and technology instruments flying on NASA’s next Commercial Lunar Payload Services (CLPS) flight as part of the Blue Ghost Misison-1. Developed by Aegis Aerospace of Webster, Texas, RAC is designed to study how lunar dust reacts to more than a dozen different types of material samples, located on the payload’s wheels. Photo courtesy Firefly Aerospace The Moon may look like barren rock, but it’s actually covered in a layer of gravel, pebbles, and dust collectively known as “lunar regolith.” During the Apollo Moon missions, astronauts learned firsthand that the fine, powdery dust – electromagnetically charged due to constant bombardment by solar and cosmic particles – is extremely abrasive and clings to everything: gloves, boots, vehicles, and mechanical equipment. What challenges does that dust pose to future Artemis-era missions to establish long-term outposts on the lunar surface?
That’s the task of an innovative science instrument called RAC-1 (Regolith Adherence Characterization), one of 10 NASA payloads flying aboard the next delivery for the agency’s CLPS (Commercial Lunar Payload Services) initiative and set to be carried to the surface by Firefly Aerospace’s Blue Ghost 1 lunar lander.
Developed by Aegis Aerospace of Webster, Texas, RAC will expose 15 sample materials – fabrics, paint coatings, optical systems, sensors, solar cells, and more – to the lunar environment to determine how tenaciously the lunar dust sticks to each one. The instrument will measure accumulation rates during landing and subsequent routine lander operations, aiding identification of those materials which best repel or shed dust. The data will help NASA and its industry partners more effectively test, upgrade, and protect spacecraft, spacesuits, habitats, and equipment in preparation for continued exploration of the Moon under the Artemis campaign.
“Lunar regolith is a sticky challenge for long-duration expeditions to the surface,” said Dennis Harris, who manages the RAC payload for NASA’s CLPS initiative at the agency’s Marshall Space Flight Center in Huntsville, Alabama. “Dust gets into gears, sticks to spacesuits, and can block optical properties. RAC will help determine the best materials and fabrics with which to build, delivering more robust, durable hardware, products, and equipment.”
Under the CLPS model, NASA is investing in commercial delivery services to the Moon to enable industry growth and support long-term lunar exploration. As a primary customer for CLPS deliveries, NASA aims to be one of many customers on future flights. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the development of seven of the 10 CLPS payloads carried on Firefly’s Blue Ghost lunar lander.
Learn more about. CLPS and Artemis at:
https://www.nasa.gov/clps
Alise Fisher
Headquarters, Washington
202-358-2546
Alise.m.fisher@nasa.gov
Headquarters, Washington
202-358-2546
Alise.m.fisher@nasa.gov
Corinne Beckinger
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034
corinne.m.beckinger@nasa.gov
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Last Updated Dec 20, 2024 EditorBeth RidgewayContactCorinne M. Beckingercorinne.m.beckinger@nasa.govLocationMarshall Space Flight Center Related Terms
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By NASA
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
The six SCALPSS cameras mounted around the base of Blue Ghost will collect imagery during and after descent and touchdown. Using a technique called stereo photogrammetry, researchers at Langley will use the overlapping images to produce a 3D view of the surface. Image courtesy of Firefly. Say cheese again, Moon. We’re coming in for another close-up.
For the second time in less than a year, a NASA technology designed to collect data on the interaction between a Moon lander’s rocket plume and the lunar surface is set to make the long journey to Earth’s nearest celestial neighbor for the benefit of humanity.
Developed at NASA’s Langley Research Center in Hampton, Virginia, Stereo Cameras for Lunar Plume-Surface Studies (SCALPSS) is an array of cameras placed around the base of a lunar lander to collect imagery during and after descent and touchdown. Using a technique called stereo photogrammetry, researchers at Langley will use the overlapping images from the version of SCALPSS on Firefly’s Blue Ghost — SCALPSS 1.1 — to produce a 3D view of the surface. An earlier version, SCALPSS 1.0, was on Intuitive Machines’ Odysseus spacecraft that landed on the Moon last February. Due to mission contingencies that arose during the landing, SCALPSS 1.0 was unable to collect imagery of the plume-surface interaction. The team was, however, able to operate the payload in transit and on the lunar surface following landing, which gives them confidence in the hardware for 1.1.
The SCALPSS 1.1 payload has two additional cameras — six total, compared to the four on SCALPSS 1.0 — and will begin taking images at a higher altitude, prior to the expected onset of plume-surface interaction, to provide a more accurate before-and-after comparison.
These images of the Moon’s surface won’t just be a technological novelty. As trips to the Moon increase and the number of payloads touching down in proximity to one another grows, scientists and engineers need to be able to accurately predict the effects of landings.
How much will the surface change? As a lander comes down, what happens to the lunar soil, or regolith, it ejects? With limited data collected during descent and landing to date, SCALPSS will be the first dedicated instrument to measure the effects of plume-surface interaction on the Moon in real time and help to answer these questions.
“If we’re placing things – landers, habitats, etc. – near each other, we could be sand blasting what’s next to us, so that’s going to drive requirements on protecting those other assets on the surface, which could add mass, and that mass ripples through the architecture,” said Michelle Munk, principal investigator for SCALPSS and acting chief architect for NASA’s Space Technology Mission Directorate at NASA Headquarters in Washington. “It’s all part of an integrated engineering problem.”
Under the Artemis campaign, the agency’s current lunar exploration approach, NASA is collaborating with commercial and international partners to establish the first long-term presence on the Moon. On this CLPS (Commercial Lunar Payload Services) initiative delivery carrying over 200 pounds of NASA science experiments and technology demonstrations, SCALPSS 1.1 will begin capturing imagery from before the time the lander’s plume begins interacting with the surface until after the landing is complete.
The final images will be gathered on a small onboard data storage unit before being sent to the lander for downlink back to Earth. The team will likely need at least a couple of months to
process the images, verify the data, and generate the 3D digital elevation maps of the surface. The expected lander-induced erosion they reveal probably won’t be very deep — not this time, anyway.
One of the SCALPSS cameras is visible here mounted to the Blue Ghost lander.Image courtesy of Firefly. “Even if you look at the old Apollo images — and the Apollo crewed landers were larger than these new robotic landers — you have to look really closely to see where the erosion took place,” said Rob Maddock, SCALPSS project manager at Langley. “We’re anticipating something on the order of centimeters deep — maybe an inch. It really depends on the landing site and how deep the regolith is and where the bedrock is.”
But this is a chance for researchers to see how well SCALPSS will work as the U.S. advances human landing systems as part of NASA’s plans to explore more of the lunar surface.
“Those are going to be much larger than even Apollo. Those are large engines, and they could conceivably dig some good-sized holes,” said Maddock. “So that’s what we’re doing. We’re collecting data we can use to validate the models that are predicting what will happen.”
The SCALPSS 1.1 project is funded by the Space Technology Mission Directorate’s Game Changing Development Program.
NASA is working with several American companies to deliver science and technology to the lunar surface under the CLPS initiative. Through this opportunity, various companies from a select group of vendors bid on delivering payloads for NASA including everything from payload integration and operations, to launching from Earth and landing on the surface of the Moon.
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Last Updated Dec 19, 2024 EditorAngelique HerringLocationNASA Langley Research Center Related Terms
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By NASA
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
Seen at the center of this image, NASA’s retired InSight Mars lander was captured by the agency’s Mars Reconnaissance Orbiter using its High-Resolution Imagine Science Experiment (HiRISE) camera on Oct. 23, 2024.NASA/JPL-Caltech/University of Arizona New images taken from space show how dust on and around InSight is changing over time — information that can help scientists learn more about the Red Planet.
NASA’s Mars Reconnaissance Orbiter (MRO) caught a glimpse of the agency’s retired InSight lander recently, documenting the accumulation of dust on the spacecraft’s solar panels. In the new image taken Oct. 23 by MRO’s High-Resolution Imaging Science Experiment (HiRISE) camera, InSight’s solar panels have acquired the same reddish-brown hue as the rest of the planet.
After touching down in November 2018, the lander was the first to detect the Red Planet’s marsquakes, revealing details of the crust, mantle, and core in the process. Over the four years that the spacecraft collected science, engineers at NASA’s Jet Propulsion Laboratory in Southern California, which led the mission, used images from InSight’s cameras and MRO’s HiRISE to estimate how much dust was settling on the stationary lander’s solar panels, since dust affected its ability to generate power.
NASA retired InSight in December 2022, after the lander ran out of power and stopped communicating with Earth during its extended mission. But engineers continued listening for radio signals from the lander in case wind cleared enough dust from the spacecraft’s solar panels for its batteries to recharge. Having detected no changes over the past two years, NASA will stop listening for InSight at the end of this year.
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NASA’s InSight Mars lander acquires the same reddish-brown hue as the rest of the planet in a set of images from 2018 to 2024 that were captured by the agency’s Mars Reconnaissance Orbiter using its High-Resolution Imagine Science Experiment (HiRISE) camera.NASA/JPL-Caltech/University of Arizona Scientists requested the recent HiRISE image as a farewell to InSight, as well as to monitor how its landing site has changed over time.
“Even though we’re no longer hearing from InSight, it’s still teaching us about Mars,” said science team member Ingrid Daubar of Brown University in Providence, Rhode Island. “By monitoring how much dust collects on the surface — and how much gets vacuumed away by wind and dust devils — we learn more about the wind, dust cycle, and other processes that shape the planet.”
Dust Devils and Craters
Dust is a driving force across Mars, shaping both the atmosphere and landscape. Studying it helps scientists understand the planet and engineers prepare for future missions (solar-powered and otherwise), since dust can get into sensitive mechanical parts.
When InSight was still active, scientists matched MRO images of dust devil tracks winding across the landscape with data from the lander’s wind sensors, finding these whirling weather phenomena subside in the winter and pick up again in the summer.
The imagery also helped with the study of meteoroid impacts on the Martian surface. The more craters a region has, the older the surface there is. (This isn’t the case with Earth’s surface, which is constantly recycled as tectonic plates slide over one another.) The marks around these craters fade with time. Understanding how fast dust covers them helps to ascertain a crater’s age.
Another way to estimate how quickly craters fade has been studying the ring of blast marks left by InSight’s retrorocket thrusters during landing. Much more prominent in 2018, those dark marks are now returning to the red-brown color of the surrounding terrain.
HiRISE has captured many other spacecraft images, including those of NASA’s Perseverance and Curiosity rovers, which are still exploring Mars, as well as inactive missions, like the Spirit and Opportunity rovers and the Phoenix lander.
“It feels a little bittersweet to look at InSight now. It was a successful mission that produced lots of great science. Of course, it would have been nice if it kept going forever, but we knew that wouldn’t happen,” Daubar said.
More About MRO and InSight
The University of Arizona, in Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., in Boulder, Colorado. A division of Caltech in Pasadena, California, JPL manages the MRO project and managed InSight for NASA’s Science Mission Directorate, Washington.
The InSight mission was part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supported spacecraft operations for the mission.
A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), supported the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the temperature and wind sensors.
For more about the missions:
https://science.nasa.gov/mission/insight
science.nasa.gov/mission/mars-reconnaissance-orbiter
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NASA Headquarters, Washington
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Last Updated Dec 16, 2024 Related Terms
InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) Jet Propulsion Laboratory Mars Mars Reconnaissance Orbiter (MRO) Radioisotope Power Systems (RPS) Explore More
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By NASA
5 Min Read NASA Technologies Aim to Solve Housekeeping’s Biggest Issue – Dust
This artist rendering of Electrostatic Dust Lofting (EDL) examines the lofting of lunar dust when electrostatic charging occurs after exposure to ultraviolet light. If you thought the dust bunnies under your sofa were an issue, imagine trying to combat dust on the Moon. Dust is a significant challenge for astronauts living and working on the lunar surface. So, NASA is developing technologies that mitigate dust buildup enabling a safer, sustainable presence on the Moon.
A flight test aboard a suborbital rocket system that will simulate lunar gravity is the next step in understanding how dust mitigation technologies can successfully address this challenge. During the flight test with Blue Origin, seven technologies developed by NASA’s Game Changing Development program within the agency’s Space Technology Mission Directorate will study regolith mechanics and lunar dust transport in a simulated lunar gravity environment.
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The technologies featured in this animation are Electrostatic Dust Lofting (EDL), Electrodynamic Regolith Conveyor (ERC), Hermes Lunar-G, ISRU Pilot Excavator (IPEx), Clothbot, Duneflow, and Vertical Lunar Regolith Conveyor (VLRC). Each of these technology payloads will advance our understanding of regolith mechanics and lunar dust transport through flight testing in space with simulated lunar gravity.NASA / Advanced Concepts Lab Why Is Lunar Dust a Problem?
With essentially no atmosphere, dust gets lofted, or lifted by the surface, by a spacecraft’s plumes as it lands on the lunar surface. But it can also be lofted through electrostatic charges. Lunar dust is electrostatic and ferromagnetic, meaning it adheres to anything that carries a charge.
Kristen John, NASA’s Lunar Surface Innovation Initiative technical integration lead at Johnson Space Center said, “The fine grain nature of dust contains particles that are smaller than the human eye can see, which can make a contaminated surface appear to look clean.”
Although lunar dust can appear smooth with a powder like finish, its particles actually have a jagged shape. Lunar dust can scratch everything from a spacesuit to human lungs. Dust can also prevent hardware from surviving the lunar night when it accumulates on solar panels causing a reduction in available power. A buildup of dust coats thermal radiators, increasing the temperature of the equipment. Lunar dust can also accumulate on windows, camera lenses, and visors leading to obscured vision.
Dirty Moon? Clean It Up.
The projects being tested on the lunar gravity flight with Blue Origin include ClothBot, Electrostatic Dust Lofting (EDL), and Hermes Lunar-G.
ClothBot
When future astronauts perform extra-vehicular activities on the lunar surface they could bring dust into pressurized, habitable areas. The goal of the ClothBot experiment is to mimic and measure the transport of lunar dust as releases from a small patch of spacesuit fabric. When agitated by pre-programmed motions, the compact robot can simulate “doffing,” the movement that occurs when removing a spacesuit. A laser-illuminated imaging system will capture the dust flow in real-time, while sensors record the size and number of particles traveling through the space. This data will be used to understand dust generation rates inside a lander or airlock from extra-vehicular activity and refine models of lunar dust transport for future lunar and potential Martian missions.
Electrostatic Dust Lofting
This technology will examine the lofting of lunar dust when electrostatic charging occurs after exposure to ultraviolet light. The EDL’s camera with associated lights will record and illuminate for the duration of the flight. During the lunar gravity phase of the flight, a vacuum door containing the dust sample will release and the ultraviolet light source will illuminate the substance, charging the grains until they electrostatically repel one another and become lofted. The lofted dust will pass through a sheet laser as it rises up from the surface. When the lunar gravity phase ends, the ultraviolet light source disables, and the camera will continue recording until the end of the flight. This data will inform dust mitigation modeling efforts for future Moon missions.
Hermes Lunar-G
NASA partnered with Texas A&M and Texas Space Technology Applications and Research (T STAR) to develop Hermes Lunar-G, technology that utilizes flight-proven hardware to conduct experiments with regolith simulants. Hermes was previously a facility on the International Space Station. Hermes Lunar-G repurposed Hermes hardware to study lunar regolith simulants. The Hermes Lunar-G technology uses four canisters to compress the simulants during flight, takeoff, and landing. When the technology is in lunar gravity, it will decompress the contents of the canisters while high-speed imagery and sensors capture data. Results of this experiment will provide information on regolith mechanics that can be used in a variety of computational models. The results of Hermes Lunar-G will be compared to microgravity data from the space station as well as similar data acquired from parabolic flights for lunar and microgravity flight profiles.
The Future of Dust Mitigation
As a primary challenge of lunar exploration, dust mitigation influences several NASA technology developments. Capabilities from In-Situ Resource Utilization to surface power and mobility, rely on some form of dust mitigation, making it a cross-cutting area.
Learning some of the fundamental properties of how lunar dust behaves and how lunar dust impacts systems has implications far beyond dust mitigation and environments. Advancing our understanding of the behavior of lunar dust and advancing our dust mitigation technologies benefits most capabilities planned for use on the lunar surface."
Kristen John
NASA’s Lunar Surface Innovation Initiative Technical Integration Lead
Engineering teams perform a variety of tests to mitigate dust, ensuring it doesn’t cause damage to hardware that goes to the Moon. NASA’s Game Changing Development program, created a reference guide for lunar dust mitigation to help engineers build hardware destined for the lunar surface.
NASA’s Flight Opportunities program funded the Blue Origin flight test as well as the vehicle capability enhancements to enable the simulation of lunar gravity during suborbital rocket flight for the first time. The payloads are managed under NASA’s Game Changing Development program within the agency’s Space Technology Mission Directorate.
To learn more visit: https://www.nasa.gov/stmd-game-changing-development/
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Last Updated Dec 13, 2024 Related Terms
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By NASA
9 Min Read Towards Autonomous Surface Missions on Ocean Worlds
Artist’s concept image of a spacecraft lander with a robot arm on the surface of Europa. Credits:
NASA/JPL – Caltech Through advanced autonomy testbed programs, NASA is setting the groundwork for one of its top priorities—the search for signs of life and potentially habitable bodies in our solar system and beyond. The prime destinations for such exploration are bodies containing liquid water, such as Jupiter’s moon Europa and Saturn’s moon Enceladus. Initial missions to the surfaces of these “ocean worlds” will be robotic and require a high degree of onboard autonomy due to long Earth-communication lags and blackouts, harsh surface environments, and limited battery life.
Technologies that can enable spacecraft autonomy generally fall under the umbrella of Artificial Intelligence (AI) and have been evolving rapidly in recent years. Many such technologies, including machine learning, causal reasoning, and generative AI, are being advanced at non-NASA institutions.
NASA started a program in 2018 to take advantage of these advancements to enable future icy world missions. It sponsored the development of the physical Ocean Worlds Lander Autonomy Testbed (OWLAT) at NASA’s Jet Propulsion Laboratory in Southern California and the virtual Ocean Worlds Autonomy Testbed for Exploration, Research, and Simulation (OceanWATERS) at NASA’s Ames Research Center in Silicon Valley, California.
NASA solicited applications for its Autonomous Robotics Research for Ocean Worlds (ARROW) program in 2020, and for the Concepts for Ocean worlds Life Detection Technology (COLDTech) program in 2021. Six research teams, based at universities and companies throughout the United States, were chosen to develop and demonstrate autonomy solutions on OWLAT and OceanWATERS. These two- to three-year projects are now complete and have addressed a wide variety of autonomy challenges faced by potential ocean world surface missions.
OWLAT
OWLAT is designed to simulate a spacecraft lander with a robotic arm for science operations on an ocean world body. The overall OWLAT architecture including hardware and software components is shown in Figure 1. Each of the OWLAT components is detailed below.
Figure 1. The software and hardware components of the Ocean Worlds Lander Autonomy Testbed and the relationships between them. NASA/JPL – Caltech The hardware version of OWLAT (shown in Figure 2) is designed to physically simulate motions of a lander as operations are performed in a low-gravity environment using a six degrees-of-freedom (DOF) Stewart platform. A seven DOF robot arm is mounted on the lander to perform sampling and other science operations that interact with the environment. A camera mounted on a pan-and-tilt unit is used for perception. The testbed also has a suite of onboard force/torque sensors to measure motion and reaction forces as the lander interacts with the environment. Control algorithms implemented on the testbed enable it to exhibit dynamics behavior as if it were a lightweight arm on a lander operating in different gravitational environments.
Figure 2. The Ocean Worlds Lander Autonomy Testbed. A scoop is mounted to the end of the testbed robot arm. NASA/JPL – Caltech The team also developed a set of tools and instruments (shown in Figure 3) to enable the performance of science operations using the testbed. These various tools can be mounted to the end of the robot arm via a quick-connect-disconnect mechanism. The testbed workspace where sampling and other science operations are conducted incorporates an environment designed to represent the scene and surface simulant material potentially found on ocean worlds.
Figure 3. Tools and instruments designed to be used with the testbed. NASA/JPL – Caltech The software-only version of OWLAT models, visualizes, and provides telemetry from a high-fidelity dynamics simulator based on the Dynamics And Real-Time Simulation (DARTS) physics engine developed at JPL. It replicates the behavior of the physical testbed in response to commands and provides telemetry to the autonomy software. A visualization from the simulator is shown on Figure 4.
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Figure 7. Screenshot of OceanWATERS lander on a terrain modeled from the Atacama Desert. A scoop operation has just been completed. NASA/JPL – Caltech The autonomy software module shown at the top in Figure 1 interacts with the testbed through a Robot Operating System (ROS)-based interface to issue commands and receive telemetry. This interface is defined to be identical to the OceanWATERS interface. Commands received from the autonomy module are processed through the dispatcher/scheduler/controller module (blue box in Figure 1) and used to command either the physical hardware version of the testbed or the dynamics simulation (software version) of the testbed. Sensor information from the operation of either the software-only or physical testbed is reported back to the autonomy module using a defined telemetry interface. A safety and performance monitoring and evaluation software module (red box in Figure 1) ensures that the testbed is kept within its operating bounds. Any commands causing out of bounds behavior and anomalies are reported as faults to the autonomy software module.
Figure 5. Erica Tevere (at the operator’s station) and Ashish Goel (at the robot arm) setting up the OWLAT testbed for use. NASA/JPL – Caltech OceanWATERS
At the time of the OceanWATERS project’s inception, Jupiter’s moon Europa was planetary science’s first choice in searching for life. Based on ROS, OceanWATERS is a software tool that provides a visual and physical simulation of a robotic lander on the surface of Europa (see Figure 6). OceanWATERS realistically simulates Europa’s celestial sphere and sunlight, both direct and indirect. Because we don’t yet have detailed information about the surface of Europa, users can select from terrain models with a variety of surface and material properties. One of these models is a digital replication of a portion of the Atacama Desert in Chile, an area considered a potential Earth-analog for some extraterrestrial surfaces.
Figure 6. Screenshot of OceanWATERS. NASA/JPL – Caltech JPL’s Europa Lander Study of 2016, a guiding document for the development of OceanWATERS, describes a planetary lander whose purpose is collecting subsurface regolith/ice samples, analyzing them with onboard science instruments, and transmitting results of the analysis to Earth.
The simulated lander in OceanWATERS has an antenna mast that pans and tilts; attached to it are stereo cameras and spotlights. It has a 6 degree-of-freedom arm with two interchangeable end effectors—a grinder designed for digging trenches, and a scoop for collecting ground material. The lander is powered by a simulated non-rechargeable battery pack. Power consumption, the battery’s state, and its remaining life are regularly predicted with the Generic Software Architecture for Prognostics (GSAP) tool. To simulate degraded or broken subsystems, a variety of faults (e.g., a frozen arm joint or overheating battery) can be “injected” into the simulation by the user; some faults can also occur “naturally” as the simulation progresses, e.g., if components become over-stressed. All the operations and telemetry (data measurements) of the lander are accessible via an interface that external autonomy software modules can use to command the lander and understand its state. (OceanWATERS and OWLAT share a unified autonomy interface based on ROS.) The OceanWATERS package includes one basic autonomy module, a facility for executing plans (autonomy specifications) written in the PLan EXecution Interchange Language, or PLEXIL. PLEXIL and GSAP are both open-source software packages developed at Ames and available on GitHub, as is OceanWATERS.
Mission operations that can be simulated by OceanWATERS include visually surveying the landing site, poking at the ground to determine its hardness, digging a trench, and scooping ground material that can be discarded or deposited in a sample collection bin. Communication with Earth, sample analysis, and other operations of a real lander mission, are not presently modeled in OceanWATERS except for their estimated power consumption. Figure 7 is a video of OceanWATERS running a sample mission scenario using the Atacama-based terrain model.
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Figure 7. Screenshot of OceanWATERS lander on a terrain modeled from the Atacama Desert. A scoop operation has just been completed. NASA/JPL – Caltech Because of Earth’s distance from the ocean worlds and the resulting communication lag, a planetary lander should be programmed with at least enough information to begin its mission. But there will be situation-specific challenges that will require onboard intelligence, such as deciding exactly where and how to collect samples, dealing with unexpected issues and hardware faults, and prioritizing operations based on remaining power.
Results
All six of the research teams funded by the ARROW and COLDTech programs used OceanWATERS to develop ocean world lander autonomy technology and three of those teams also used OWLAT. The products of these efforts were published in technical papers, and resulted in development of software that may be used or adapted for actual ocean world lander missions in the future. The following table summarizes the ARROW and COLDTech efforts.
Principal Investigator (PI) PI Institution Project Testbed Used Purpose of Project ARROW Projects Jonathan Bohren Honeybee Robotics Stochastic PLEXIL (SPLEXIL) OceanWATERS Extended PLEXIL with stochastic decision-making capabilities by employing reinforcement learning techniques. Pooyan Jamshidi University of South Carolina Resource Adaptive Software Purpose-Built for Extraordinary Robotic Research Yields (RASPBERRY SI) OceanWATERS & OWLAT Developed software algorithms and tools for fault root cause identification, causal debugging, causal optimization, and causal-induced verification. COLDTech Projects Eric Dixon Lockheed Martin Causal And Reinforcement Learning (CARL) for COLDTech OceanWATERS Integrated a model of JPL’s mission-ready Cold Operable Lunar Deployable Arm (COLDarm) into OceanWATERS and applied image analysis, causal reasoning, and machine learning models to identify and mitigate the root causes of faults, such as ice buildup on the arm’s end effector. Jay McMahon University of Colorado Robust Exploration with Autonomous Science On-board, Ranked Evaluation of Contingent Opportunities for Uninterrupted Remote Science Exploration (REASON-RECOURSE) OceanWATERS Applied automated planning with formal methods to maximize science return of the lander while minimizing communication with ground team on Earth. Melkior Ornik U Illinois, Urbana-Champaign aDaptive, ResIlient Learning-enabLed oceAn World AutonomY (DRILLAWAY) OceanWATERS & OWLAT Developed autonomous adaptation to novel terrains and selecting scooping actions based on the available image data and limited experience by transferring the scooping procedure learned from a low-fidelity testbed to the high-fidelity OWLAT testbed. Joel Burdick Caltech Robust, Explainable Autonomy for Scientific Icy Moon Operations (REASIMO) OceanWATERS & OWLAT Developed autonomous 1) detection and identification of off-nominal conditions and procedures for recovery from those conditions, and 2) sample site selection Acknowledgements: The portion of the research carried out at the Jet Propulsion Laboratory, California Institute of Technology was performed under a contract with the National Aeronautics and Space Administration (80NM0018D0004). The portion of the research carried out by employees of KBR Wyle Services LLC at NASA Ames Research Center was performed under a contract with the National Aeronautics and Space Administration (80ARC020D0010). Both were funded by the Planetary Science Division ARROW and COLDTech programs.
Project Leads: Hari Nayar (NASA Jet Propulsion Laboratory, California Institute of Technology), K. Michael Dalal (KBR, Inc. at NASA Ames Research Center)
Sponsoring Organizations: NASA SMD PESTO
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