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At least 1,081 records · Page 60

What is the Role of Usability and Trust in Autonomy?

Usability encompasses learnability, efficiency, memorability, effectiveness, and satisfaction. NASA’s standards for usability acceptance criteria focus on interfaces that help operators achieve their tasks efficiently, effectively, and with satisfaction. However, discussions on usability, especially regarding future highly automated and autonomous systems, rarely include trust. As NASA plans for long-duration exploration missions, it envisions astronauts operating more independently from Mission Control on Earth. This independence will drive the development of these highly automated and autonomous systems that astronauts will use daily. To prepare for this future, our team has developed a scheduling and execution software tool that facilitates self-scheduling, allowing astronauts to independently manage their own schedule without Mission Control’s involvement. Over many years, we have developed, matured, and evaluated our software tool in extreme environments, prioritizing user-centered design and high usability. These evaluations have included multiple campaigns in NASA analogs, including NEEMO, BASALT, and HERA, as well as technology demonstrations onboard the International Space Station. Our recent research on software interfaces for future astronaut autonomy revealed a strong correlation between usability and trust measures. In a controlled lab experiment, we asked novice users to perform a complex scheduling task, during which the software immediately validated the schedule’s constraints and checked for violations. We collected usability (User Experience Questionnaire, UEQ) and trust (Trust in Automated Systems scale, TAS) measures; significant, strong, and moderate correlations emerged between several of the UEQ metrics and TAS. These results support the argument for investing in usability early to enable and sustain trust in highly automated and autonomous systems.

usability↗

Fuzzy set approach to quality function deployment: An investigation

The final report of the 1992 NASA/ASEE Summer Faculty Fellowship at the Space Exploration Initiative Office (SEIO) in Langley Research Center is presented. Quality Function Deployment (QFD) is a process, focused on facilitating the integration of the customer's voice in the design and development of a product or service. Various input, in the form of judgements and evaluations, are required during the QFD analyses. All the input variables in these analyses are treated as numeric variables. The purpose of the research was to investigate how QFD analyses can be performed when some or all of the input variables are treated as linguistic variables with values expressed as fuzzy numbers. The reason for this consideration is that human judgement, perception, and cognition are often ambiguous and are better represented as fuzzy numbers. Two approaches for using fuzzy sets in QFD have been proposed. In both cases, all the input variables are considered as linguistic variables with values indicated as linguistic expressions. These expressions are then converted to fuzzy numbers. The difference between the two approaches is due to how the QFD computations are performed with these fuzzy numbers. In Approach 1, the fuzzy numbers are first converted to their equivalent crisp scores and then the QFD computations are performed using these crisp scores. As a result, the output of this approach are crisp numbers, similar to those in traditional QFD. In Approach 2, all the QFD computations are performed with the fuzzy numbers and the output are fuzzy numbers also. Both the approaches have been explained with the help of illustrative examples of QFD application. Approach 2 has also been applied in a QFD application exercise in SEIO, involving a 'mini moon rover' design. The mini moon rover is a proposed tele-operated vehicle that will traverse and perform various tasks, including autonomous operations, on the moon surface. The output of the moon rover application exercise is a ranking of the rover functions so that a subset of these functions can be targeted for design improvement. The illustrative examples and the mini rover application exercise confirm that the proposed approaches for using fuzzy sets in QFD are viable. However, further research is needed to study the various issues involved and to verify/validate the methods proposed.

Masud, Abu S. M.↗

A Dive into Underwater Solar Cells

Our oceans are vast, mostly unexplored and difficult to monitor. Large-scale implementation of a fully autonomous 'Internet of Underwater Things' would transform how we collect and share data from this domain; however, deployment is prohibited by the lack of persistent power sources. In principle, underwater solar-energy generation can complement the use of batteries and provide a solution, although dedicated research is needed since traditional silicon solar cells do not perform well underwater due to water's strong absorption of near-infrared light. In this Perspective we present examples of solar-powered underwater applications and discuss which types of solar-harvesting materials could be appropriate, including GaInP variants, CdTe, organic semiconductors, and perovskite semiconductors. We also discuss challenges that need to be addressed, such as the development of effective antifouling coatings and new certification standards given that underwater conditions are starkly different from those in terrestrial environments.

antifouling coatings↗

X-34 Vehicle Aerodynamic Characteristics

The X-34, being designed and built by the Orbital Sciences Corporation, is an unmanned sub-orbital vehicle designed to be used as a flying test bed to demonstrate key vehicle and operational technologies applicable to future reusable launch vehicles. The X-34 will be air-launched from an L-1011 carrier aircraft at approximately Mach 0.7 and 38,000 feet altitude, where an onboard engine will accelerate the vehicle to speeds above Mach 7 and altitudes to 250,000 feet. An unpowered entry will follow, including an autonomous landing. The X-34 will demonstrate the ability to fly through inclement weather, land horizontally at a designated site, and have a rapid turn-around capability. A series of wind tunnel tests on scaled models was conducted in four facilities at the NASA Langley Research Center to determine the aerodynamic characteristics of the X-34. Analysis of these test results revealed that longitudinal trim could be achieved throughout the design trajectory. The maximum elevon deflection required to trim was only half of that available, leaving a margin for gust alleviation and aerodynamic coefficient uncertainty. Directional control can be achieved aerodynamically except at combined high Mach numbers and high angles of attack, where reaction control jets must be used. The X-34 landing speed, between 184 and 206 knots, is within the capabilities of the gear and tires, and the vehicle has sufficient rudder authority to control the required 30-knot crosswind.

Brauckmann, Gregory J.↗

Autonomous aircraft initiative study

The results of a consulting effort to aid NASA Ames-Dryden in defining a new initiative in aircraft automation are described. The initiative described is a multi-year, multi-center technology development and flight demonstration program. The initiative features the further development of technologies in aircraft automation already being pursued at multiple NASA centers and Department of Defense (DoD) research and Development (R and D) facilities. The proposed initiative involves the development of technologies in intelligent systems, guidance, control, software development, airborne computing, navigation, communications, sensors, unmanned vehicles, and air traffic control. It involves the integration and implementation of these technologies to the extent necessary to conduct selected and incremental flight demonstrations.

Hewett, Marle D.↗

Basic Research Needs Workshop on Synthesis Science for Energy Relevant Technology

The technology that lies at our fingertips becomes more powerful each day. Smartphones connect us instantly to family, friends, and co-workers around the globe; give us access to a limitless stream of information; control the heating in our homes; and serve as our cameras, calculators, flashlights, music players, boarding passes and, on occasion, our phones. Cars are ever more fuel-efficient, safer, semi-autonomous, and have more computing power than the systems that guided humankind to the moon. LED lighting and solar panels are becoming commonplace, replacing less efficient technologies and expanding the energy options available worldwide. Novel polymers and nanoparticles are playing a crucial role in enhanced oil recovery. None of these advances would have been possible without the discovery and development of, and ability to create, new materials and chemical processes. Now imagine what our world would be like if we could accelerate those discoveries a thousandfold. What if the only limit to synthesizing new forms of matter were the imagination? We could build complex assemblies of atoms and molecules with architectures and capabilities far exceeding those of materials found in nature—for example, develop catalysts that turn garbage into fuels, design solar cells to power our homes directly from sunlight, make batteries with the energy density of gasoline, and create one- and two-dimensional solids that transport charge hundreds of times faster than silicon or allow us to build quantum bits based on the spins of electrons or photons to realize the promise of “beyond Moore’s law” computing. Advances in synthesis science are required to bring about this future—we not only must know how to design new molecules and materials with desired functions and properties through theory and computational techniques; we also must be able to make the materials we envision. New approaches to discovering as yet unimagined matter require a sea change in the way we think about the science of synthesis. Chemical and materials sciences have traditionally focused on understanding structure–function relationships with the goal of predicting where the atoms should be placed to achieve a targeted property or process. Much less effort has been directed toward a predictive science of synthesis—understanding how to get the atoms where they need to go to achieve the desired structure. This report, which is the result of the Basic Energy Sciences Workshop on Basic Research Needs for Synthesis Science for Energy Technologies, lays out the scientific challenges and opportunities in synthesis science. The workshop was attended by more than 100 leading national and international scientific experts. Its five topical and two crosscutting panels identified four priority research directions (PRDs) for realizing the vision of predictive, science-directed synthesis.

99 GENERAL AND MISCELLANEOUS↗

Novel Ways to use the International Spacer Station as an Exploration Analog: International Progress in Planning "ISS4Mars"

In October 2020, International Space Station (ISS) Partner Agencies held a set of international workshops to solicit and develop creative and forward-looking ideas for using the ISS as an analog for preparation for Mars missions during its 3rd decade of operations. The workshops brought together participants from nine international space agencies or organizations, with stakeholders consisting of research managers, discipline experts, technology developers, flight physicians, flight operators, and astronauts. Breakout meetings and brainstorming sessions were conducted focusing on the following topics: Critical hazards and countermeasures for the transit to Mars; gravity transitions and early surface operations; environmental control and life support systems; food systems; human microbiome, microbial monitoring, and planetary protection; medical operations for Mars missions; isolation and confinement; autonomous systems and crew-centered autonomy; and communications delay effects on operations. In many cases the scenarios and approaches identified were compelling but challenging to implement under the current utilization structure used to manage the ISS for experiments. Following the series of workshops, a team of utilization leaders across the ISS partnership worked to compile the workshop recommendations and extract a set of use-cases with their prerequisites and constraints. The work considered the following aspects: what can be effectively done on ISS; which new technologies, approaches and scenarios are feasible; what alternatives could be considered; and what steps should be taken to enable integrated testing and future use of ISS as an analog for Mars missions. The final report will be published so that the use cases can be considered in each agency’s strategic planning processes. This paper will cover the process of international assessment in detail and how this process has influenced and broadened the vision of ISS utilization beyond single experiments to integrated studies and testing for future Mars missions. This approach to international collaboration informs both the next decade of international exploration research on the ISS and advancement of its utilization as an analog for deep space missions. For many of the participating partners, it also helps to frame the strategy for human research in Artemis as we begin planning for human missions to the moon. We conclude with a summary of the progress on the actions in the report and the additional implementation discussions that have occurred across the partnership.

Julie A Robinson↗

Automated Rendezvous and Capture System Development and Simulation for NASA

The United States does not have an Automated Rendezvous and Capture/Docking (AR and C) capability and is reliant on manned control for rendezvous and docking of orbiting spacecraft. This reliance on the labor intensive manned interface for control of rendezvous and docking vehicles has a significant impact on the cost of the operation of the International Space Station (ISS) and precludes the use of any U.S. expendable launch capabilities for Space Station resupply. The Soviets have the capability to autonomously dock in space, but their system produces a hard docking with excessive force and contact velocity. Automated Rendezvous and Capture/Docking has been identified as a key enabling technology for the Space Launch Initiative (SLI) Program, DARPA Orbital Express and other DOD Programs. The development and implementation of an AR&C capability can significantly enhance system flexibility, improve safety, and lower the cost of maintaining, supplying, and operating the International Space Station. The Marshall Space Flight Center (MSFC) has conducted pioneering research in the development of an automated rendezvous and capture (or docking) (AR and C) system for U.S. space vehicles. This AR&C system was tested extensively using hardware-in-the-loop simulations in the Flight Robotics Laboratory, and a rendezvous sensor, the Video Guidance Sensor was developed and successfully flown on the Space Shuttle on flights STS-87 and STS-95, proving the concept of a video- based sensor. Further developments in sensor technology and vehicle and target configuration have lead to continued improvements and changes in AR&C system development and simulation. A new Advanced Video Guidance Sensor (AVGS) with target will be utilized on the Demonstration of Autonomous Rendezvous Technologies (DART) flight experiment in 2004.

Roe, Fred D.↗

Space Missions for Automation and Robotics Technologies (SMART) Program

NASA is currently considering the establishment of a Space Mission for Automation and Robotics Technologies (SMART) Program to define, develop, integrate, test, and operate a spaceborne national research facility for the validation of advanced automation and robotics technologies. Initially, the concept is envisioned to be implemented through a series of shuttle based flight experiments which will utilize telepresence technologies and real time operation concepts. However, eventually the facility will be capable of a more autonomous role and will be supported by either the shuttle or the space station. To ensure incorporation of leading edge technology in the facility, performance capability will periodically and systematically be upgraded by the solicitation of recommendations from a user advisory group. The facility will be managed by NASA, but will be available to all potential investigators. Experiments for each flight will be selected by a peer review group. Detailed definition and design is proposed to take place during FY 86, with the first SMART flight projected for FY 89.

Cliffone, D. L.↗

Space Medicine: A Surgeon's Perspective

For the first four decades of human space flight NASA's priorities in life sciences and medical programs have been preventative medicine (astronaut selection and training); assessment of the physiologic effects of microgravity and other unique aspects of space flight, implementation of countermeasures to protect against adverse effects, and amelioration of these adverse effects. Because most of the U.S. space flight experience has been on short duration missions, the need for medical and diagnostic treatment capabilities have been limited.The first long-term crews will arrive on the International Space Station (ISS) in early 2000. This will usher in a new era, an era of sustained human presence in Low Earth Orbit. One of the principal purposes of the ISS program is to increase the knowledge of the effects of long duration space flight on humans, a pre-requisite to future exploration class missions beyond Low Earth Orbit (e.g., a return to the Moon or an exploration of Mars). Areas of particular interest include protection from radiation, muscle atrophy, bone loss, cardiovascular alterations, immune dysfunction, adverse psychological response to hazards and confinement, and neurovestibular alterations. In addition, long duration space flight requires the development of autonomous medical care capabilities, as the distances involved eliminate the possibility of real-time telemedicine or robotic intervention, and prevent a mission abort and a rapid return to Earth. The objectives of this presentation include: 1. A description of the International Space Station project, including its research facilities and on-orbit medical capabilities; 2. An overview of the physiological and medical problems associated with microgravity in space flight; 3. A review of NASA's biomedical research priorities and ongoing work to develop clinical care capabilities for space flight crews (including surgical interventions) and; 4. An overview of current and proposed research priorities for NASA Research Announcements, NASA Space Biomedical Research Institute, Small Business Innovation Research Grant, and other funding sources.

Dawson, David L.↗

SPHERES as Formation Flight Algorithm Development and Validation Testbed: Current Progress and Beyond

The MIT-SSL SPHERES testbed provides a facility for the development of algorithms necessary for the success of Distributed Satellite Systems (DSS). The initial development contemplated formation flight and docking control algorithms; SPHERES now supports the study of metrology, control, autonomy, artificial intelligence, and communications algorithms and their effects on DSS projects. To support this wide range of topics, the SPHERES design contemplated the need to support multiple researchers, as echoed from both the hardware and software designs. The SPHERES operational plan further facilitates the development of algorithms by multiple researchers, while the operational locations incrementally increase the ability of the tests to operate in a representative environment. In this paper, an overview of the SPHERES testbed is first presented. The SPHERES testbed serves as a model of the design philosophies that allow for the various researches being carried out on such a facility. The implementation of these philosophies are further highlighted in the three different programs that are currently scheduled for testing onboard the International Space Station (ISS) and three that are proposed for a re-flight mission: Mass Property Identification, Autonomous Rendezvous and Docking, TPF Multiple Spacecraft Formation Flight in the first flight and Precision Optical Pointing, Tethered Formation Flight and Mars Orbit Sample Retrieval for the re-flight mission.

Kong, Edmund M.↗

Recent Stirling Conversion Technology Developments and Operational Measurements

Under contract to the Department of Energy (DOE), Lockheed Martin Space Systems Company (LMSSC) has been developing the Advanced Stirling Radioisotope Generator (ASRG). The use of Stirling technology introduces a four-fold increase in conversion efficiency over Radioisotope Thermoelectric Generators (RTGs), and thus the ASRG in an attractive power system option for future science missions. In August of 2008, the ASRG engineering unit (EU) was delivered to NASA Glenn Research Center (GRC). The engineering unit design resembles that of a flight unit, with the exception of electrical heating in place of a radioisotope source. Prior to delivery, GRC personnel prepared a test station continuous, unattended operation of the engineering unit. This test station is capable of autonomously monitoring the unit's safe operation and recording. , .. , .... performance data. Generator parameters recorded include temperatures, electrical power output, and thelmal power input. Convertor specific parameters are also recorded such as alternator voltage, current, piston amplitude, and frequency. Since November 2008, the ASRG EU has accumulated over 4,000 hours of operation. Initial operation was conducted using the AC bus control method in lieu of the LMSSC active power factor connecting controller. Operation on the LMSSC controller began in February 2009. This paper discusses the entirety of ASRG EU operation thus far, as well as baseline performance data at GRC and LMSSC, and comparison of performance using each control method.

Oriti, Salvatore↗

International Space Station Data Collection for Disaster Response

Remotely sensed data acquired by orbital sensor systems has emerged as a vital tool to identify the extent of damage resulting from a natural disaster, as well as providing near-real time mapping support to response efforts on the ground and humanitarian aid efforts. The International Space Station (ISS) is a unique terrestrial remote sensing platform for acquiring disaster response imagery. Unlike automated remote-sensing platforms it has a human crew; is equipped with both internal and externally-mounted remote sensing instruments; and has an inclined, low-Earth orbit that provides variable views and lighting (day and night) over 95 percent of the inhabited surface of the Earth. As such, it provides a useful complement to autonomous sensor systems in higher altitude polar orbits. NASA remote sensing assets on the station began collecting International Disaster Charter (IDC) response data in May 2012. The initial NASA ISS sensor systems responding to IDC activations included the ISS Agricultural Camera (ISSAC), mounted in the Window Observational Research Facility (WORF); the Crew Earth Observations (CEO) Facility, where the crew collects imagery using off-the-shelf handheld digital cameras; and the Hyperspectral Imager for the Coastal Ocean (HICO), a visible to near-infrared system mounted externally on the Japan Experiment Module Exposed Facility. The ISSAC completed its primary mission in January 2013. It was replaced by the very high resolution ISS SERVIR Environmental Research and Visualization System (ISERV) Pathfinder, a visible-wavelength digital camera, telescope, and pointing system. Since the start of IDC response in 2012 there have been 108 IDC activations; NASA sensor systems have collected data for thirty-two of these events. Of the successful data collections, eight involved two or more ISS sensor systems responding to the same event. Data has also been collected by International Partners in response to natural disasters, most notably JAXA and Roscosmos/Energia through the Urugan program.

Stefanov, William L.↗

Blue Carbon Stocks Along the Pacific Coast of North America Are Mainly Driven by Local Rather Than Regional Factors

Coastal wetlands, including seagrass meadows, emergent marshes, mangroves, and temperate tidal swamps, can efficiently sequester and store large quantities of sediment organic carbon (SOC). However, SOC stocks may vary by ecosystem type and along environmental or climate gradients at different scales. Quantifying such variability is needed to improve blue carbon accounting, conservation effectiveness, and restoration planning. We analyzed SOC stocks in 1,284 sediment cores along >6,500 km of the Pacific coast of North America that included large environmental gradients and multiple ecosystem types. Tidal wetlands with woody vegetation (mangroves and swamps) had the highest mean stocks to 1 m depth (357 and 355 Mg ha −1 , respectively), 45% higher than marshes (245 Mg ha −1 ), and more than 500% higher than seagrass (68 Mg ha −1 ). Unvegetated tideflats, though not often considered a blue carbon ecosystem, had noteworthy stocks (148 Mg ha −1 ). Stocks increased with tidal elevation and with fine (<63 μm) sediment content in several ecosystems. Stocks also varied by dominant plant species within individual ecosystem types. At larger scales, marsh stocks were lowest in the Sonoran Desert region of Mexico, and swamp stocks differed among climate zones; otherwise stocks showed little correlation with ecoregion or latitude. More variability in SOC occurred among ecosystem types, and at smaller spatial scales (such as individual estuaries), than across regional climate gradients. These patterns can inform coastal conservation and restoration priorities across scales where preserving stored carbon and enhancing sequestration helps avert greenhouse gas emissions and maintains other vital ecosystem services.

emergent marsh↗

Edge ML for CAN bus intrusion detection in AVs

Autonomous Vehicles (AVs) are revolutionizing transportation, but their reliance on interconnected cyber-physical systems exposes them to unprecedented cybersecurity risks. This study addresses the critical challenge of detecting real-time cyber intrusions in self-driving vehicles by leveraging a dataset from the Udacity self-driving car project. We simulate four high-impact attack vectors, Denial of Service (DoS), spoofing, replay, and fuzzy attacks, by injecting noise into spatial features (e.g., bounding box coordinates) to replicate adversarial scenarios. We develop and evaluate two lightweight neural network architectures (NN-1 and NN-2) alongside a logistic regression baseline (LG-1) for intrusion detection. The models achieve exceptional performance, with NN-2 attaining an AUC score of 93.15% and 93.15% accuracy, demonstrating their suitability for edge deployment in AV environments. Through explainable AI techniques, we uncover unique forensic fingerprints of each attack type, such as spatial corruption in fuzzy attacks and temporal anomalies in replay attacks, offering actionable insights for feature engineering and proactive defense. Visual analytics, including confusion matrices, ROC curves, and feature importance plots, validate the models' robustness and interpretability. This research sets a new benchmark for AV cybersecurity, delivering a scalable, field-ready toolkit for Original Equipment Manufacturers (OEMs) and policymakers. By aligning intrusion fingerprints with SAE J3061 automotive security standards, we provide a pathway for integrating machine learning into safety-critical AV systems. Our findings underscore the urgent need for security-by-design AI, ensuring that AVs not only drive autonomously but also defend autonomously. This work bridges the gap between theoretical cybersecurity and life-preserving engineering, offering a leap toward safer, more secure autonomous transportation.

97 MATHEMATICS AND COMPUTING↗

Autonomous Anomaly Detection for MPC Forecasts of HVAC Systems in Residential Communities

The use of residential heating, ventilation, and air conditioning (HVAC) to shift peak demand or provide ancillary services is a potential solution in the presence of older grids and distributed renewables. However, to ensure the efficient use of devices, utilities need to accurately forecast the load and adopt error correction schemes when necessary. While significant theoretical research exists in the area of predictive control of HVAC, little experimental evidence exists. The lack of experimental data in turn causes researchers to be unprepared for unsystematic errors which emerge due to the higher complexity of the data generating process. This study offers an anomaly detection methodology that uses unsupervised machine learning algorithms to detect and isolate these errors with different forecast error ranges. The results of anomaly detection procedure can then be used for error correction and would eventually help develop better predictive controllers. The methodology is tested using real world data from a smart neighborhood that currently operates in Atlanta. GA.

Lebakula, Viswadeep↗

Workshop on the Role of Design Assurance in System-Wide Safety’s Safety Demonstrator Series

This report summarizes a three-hour hybrid in-person/online workshop on June 7, 2024 on the topic of design assurance and the Safety Demonstrator Series (SDS), which was held at NASA Ames Research Center. The SDS provides an operational demonstration of, and recommendations for, requirements and standards necessary to monitor, assess, and mitigate risks to assure safety in disaster-oriented operations. Over sixty NASA personnel participated in the workshop. Four main topics were discussed: (1) assurance needs for the Safety Demonstrator Series, (2) assurance and the In-Time Aviation Safety Management System (IASMS), (3) in-time assurance: existing efforts and future opportunities, and (4) demonstrating assurance tools in the Safety Demonstrators. Key takeaways are as follows: 1. Design assurance tools can be used to assure an In-Time Aviation Safety Management System, the systems that comprise it, and other systems or missions. Assurance must consider both systems and components and include the interactions between elements in both a systems/aircraft context and a systems-of-systems/airspace context. 2. Design-time assurance activities can support the identification of monitors needed for operational assurance activities (i.e., the “monitor” function in the monitor-assess-mitigate paradigm at the heart of the IASMS concept). 3. A major opportunity for design-time assurance tools to contribute to the IASMS concept is to support rapid re-validation of systems. This will be particularly important for (1) supporting novel operations in the IASMS, where operational data may disprove design-time assumptions (motivating re-analysis of system safety) and (2) adapting technologies (e.g., AI/ML for autonomous operations) to new operational domains, where there may be new or different safety considerations not included in the initial scope of operations. 4. There are several design assurance tools under development in the System-Wide Safety project that can support assurance of Services, Functions, and Capabilities (SFCs) in the Safety Demonstrators. Transitioning these tools from one-off research projects into a functioning part of IASMS assurance will require closer integration between these tools. 5. It is not clear whether the role of design assurance tools is primarily as a part of IASMS architecture or as an external check on IASMS. The workshop consisted of four discussion topics initiated via four lightning talks by System-Wide Safety researchers. Discussions utilized Mural to engage both in-person and online participants in the hybrid format. Polls and surveys were also utilized to gather participant input. The workshop closed with a reflection activity for participants, as well as new ideas for collaboration and coordination of ongoing System-Wide Safety research.

design assurance↗

Uncovering multiscale structure-property correlations via active learning in scanning tunneling microscopy

Atomic arrangements and local sub-structures fundamentally influence emergent material functionalities. These structures are conventionally probed using spatially resolved studies and the property correlations are deciphered by a researcher based on sequential explorations, thereby limiting the efficiency and scope. Here we demonstrate a multi-scale Bayesian deep-learning based framework that automatically correlates material structure with its electronic properties using scanning tunneling microscopy (STM) measurements in real-time. Its predictions are used to autonomously direct exploration toward regions of the sample that optimize a given material property. This method is deployed on a low-temperature ultra-high vacuum STM to understand the structure-property relationship in a europium-based semimetal, EuZn 2 As 2 , a promising candidate relevant to magnetism-driven topological phenomena. The framework employs a sparse-sampling approach to efficiently construct the scalar-property space using minimal measurements, about 1–10% of the data required in standard hyperspectral methods. Moreover, we formulate the problem hierarchically across length scales, implementing autonomous workflow to locate mesoscopic and atomic structures that correspond to a target material property. This framework offers the choice to design scalar-property from the spectroscopic data to steer sample exploration. Our findings reveal correlations of the electronic properties unique to surface terminations, local defect density, and point defects.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗