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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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216 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Developing a 3-DOF Compliant Perching Arm for a Free-Flying Robot on the International Space Station

This paper presents the design and control of the 3-DOF compliant perching arm for the free-flying Astrobee robots that will operate inside the International Space Station (ISS). The robots are intended to serve as a flexible platform for future guest scientists to use for zero-gravity robotics research - thus, the arm is designed to support manipulation research. It provides a 1-DOF underactuated tendon-driven gripper capable of enveloping a range of objects of different shapes and sizes. Co-located RGB camera and LIDAR sensors provide perception. The Astrobee robots will be capable of grasping each other in flight, to simulate orbital capture scenarios. The arm's end-effector module is swappable on-orbit, allowing guest scientists to add upgraded grippers, or even additional arm degrees of freedom. The design of the arm balances research capabilities with Astrobee's operational need to perch on ISS handrails to reduce power consumption. Basic arm functioning and grip strength were evaluated using an integrated Astrobee prototype riding on a low-friction air bearing.

Park, In-Won↗
NASA NTRS2018

Robotics Platforms Incorporating Manipulators Having Common Joint Designs

Manipulators in accordance with various embodiments of the invention can be utilized to implement statically stable robots capable of both dexterous manipulation and versatile mobility. Manipulators in accordance with one embodiment of the invention include: an azimuth actuator; three elbow joints that each include two actuators that are offset to allow greater than 360 degree rotation of each joint; a first connecting structure that connects the azimuth actuator and a first of the three elbow joints; a second connecting structure that connects the first elbow joint and a second of the three elbow joints; a third connecting structure that connects the second elbow joint to a third of the three elbow joints; and an end-effector interface connected to the third of the three elbow joints.

Kennedy, Brett A.↗
NASA NTRS2016

Modeling of Active Tether System Concepts for Planetary Exploration

This paper summarizes an approach for modeling, simulation, and control of tethered systems in which the tether is actively controlled. Various aspects of the system model are described, including tether dynamics, end-effector dynamics, contact interaction and the model of the active tether material. We consider three scenarios: a tether made of an electrically switchable material for small body sampling, a tether for close-proximity operations such as capture and grappling, and a tether harpooning to a small body for sample capture or planetary fly-by.

Quadrelli, Marco B.↗
NASA NTRS1994

Technology for Robotic Surface Inspection in Space

This paper presents on-going esearch in robotic ispeciton of space platforms. Three main area of investigation are discussed: machine-vision inspection techniques, an integrated sensor end-effector, and an orbital environment laboratory simulation.

robotic↗
NASA NTRS1995

Mars Lander Robotics and Machine Vision Capabilities for in situ Planetary Science

We overview our recent progress in lander-based robotics for Mars planetary science. Utilizing a 1:1 scale laboratory replica of the NASA Mars Surveyor '98 mission, JPL engineers and Mars sciencce colleagues have demonstrated approaches to lander science functions such as robotic sample acquisiiton and deposition, end-effector based microscopic viewing, hand-carried science instrument data collection, and science instrument emplacement by a robot.

robotics↗
NASA NTRSDate not supplied

A Protoflight Lightweight Surface Manipulation System to Enable High-Load, Long-Reach Lunar Surface Operations

There is a current critical need under the Artemis program for a versatile, high-load, long reach manipulation system that can provide payload offloading and handling for lunar landers. The Lightweight Surface Manipulation System (LSMS) is a highly structurally efficient, long-reach robotic arm that can be sized for a wide range of missions and payload ranges. The LSMS has more than a decade of heritage and testing at NASA Langley Research Center (LaRC), including laboratory and field testing of multiple end-effector tools and operational scenarios. With the need for rapid development of a flight-proven offloading capability and the desire to have that device be reusable for future missions and services, a 4-year program was initiated this year under NASA’s Space Technology Mission Directorate, to develop and build a protoflight unit of the LSMS, capable of lifting 1,000 kg on the Moon at an 8-meter reach. The target mission is to fly on a large cargo lander as a technology demonstrator to validate self-leveling, deployment, and payload handling operations, with future flights adding additional tools and capabilities. This paper provides a summary of the prior decade of work on the LSMS, the current mission drivers and goals, and details the first year of development of the LSMS toward a protoflight unit.

LSMS↗
NASA NTRSDate not supplied

A Protoflight Lightweight Surface Manipulation System to Enable High-Load, Long-Reach Lunar Surface Operations

There is a current critical need under the Artemis program for a versatile, high-load, long reach manipulation system that can provide payload offloading and handling for lunar landers. The Lightweight Surface Manipulation System (LSMS) is a highly structurally efficient, long-reach robotic arm that can be sized for a wide range of missions and payload ranges. The LSMS has more than a decade of heritage and testing at NASA Langley Research Center (LaRC), including laboratory and field testing of multiple end-effector tools and operational scenarios. With the need for rapid development of a flight-proven offloading capability and the desire to have that device be reusable for future missions and services, a 4-year program was initiated this year under NASA’s Space Technology Mission Directorate, to develop and build a protoflight unit of the LSMS, capable of lifting 1,000 kg on the Moon at an 8-meter reach. The target mission is to fly on a large cargo lander as a technology demonstrator to validate self-leveling, deployment, and payload handling operations, with future flights adding additional tools and capabilities. This paper provides a summary of the prior decade of work on the LSMS, the current mission drivers and goals, and details the first year of development of the LSMS toward a protoflight unit.

lunar surface↗
NASA NTRS2022

Cable Decoupling and Cable-Based Stiffening of Continuum Robots

Cable-driven continuum robots, which are robots with a continuously flexible backbone and no identifiable joints that are actuated by cables, have shown great potential for many applications in unstructured, uncertain environments. However, the standard design for a cable-driven continuum robot segment, which bends a continuous backbone along a circular arc, has many compliant modes of deformation which are uncontrolled, and which may result in buckling or other undesirable behaviors if not ameliorated. In this paper, we detail an approach for using additional cables to selectively stiffen planar cable-driven robots with-out substantial coupling to the actuating cables. A mechanics-based model based on the planar Cosserat equations is used to find the design conditions under which additional cables can be routed without coupling of the cable lengths for small deformations. Simulations show that even for relatively large deformations, coupling remains small. A prototype is evaluated, and it is demonstrated that the compliance of the robot is substantially modified relative to the same robot without stiffening cables. Additional stiffening cables are shown to increase the end-effector output stiffness by a factor of approximately 10 over a typical design with actuating cables.

Tendon/wire mechanism↗
NASA NTRSDate not supplied

LSMS–L35, Miniature Crane for Payload Offloading and Manipulation: Development, and Application

The Lightweight Surface Manipulation System (LSMS) is a robotic agent for autonomous surface construction activities on planetary surfaces, that was designed at NASA Langley Research Center and has over a decade of research and development. The LSMS is a key component to achieving many goals of the NASA Artemis program. The LSMS is lightweight, structurally efficient system that can be easily packaged for launch and deployment on-surface, capable of a suite of surface activities enabled by modular end-effectors at the wrist. The focus of recent development work has been on using the LSMS for payload offloading and handling from lunar landers. Discussed in the paper is the development of the LSMS-L35 hardware (35 kg wrist lifting capacity on the lunar surface), designed to integrate with a Commercial Lunar Payload Services (CLPS) lander to offload payloads to the surface. The LSMS-L35 hardware development is part of a larger effort to enable autonomous payload handling and manipulation.

Iok M. Wong↗
NASA NTRSDate not supplied

Uncertainty in Servicing and Assembly Tasks for Space Robotic Manipulators

This presentation will discuss a subset of the sources of uncertainty that impact autonomous in-space servicing, assembly, and manufacturing missions. These include robotic manipulator modeling uncertainties in both kinematics and dynamics, perception error associated machine learning models for pose estimation, and sensor noise. Mitigation strategies will be discussed including the incorporation of capture envelopes in the design of robotic tools and selection of robot goal poses to minimize end-effector sensitivity in manipulators with redundant degrees of freedom.

robotics↗
NASA NTRSDate not supplied

Test Results for Autonomous Assembly of Modular Space Structures

This paper presents test results for autonomous assembly of a modular space structure. A Universal Robots UR10e manipulator with a custom end-effector, known as the Grapple Tool, was used to join TriTruss structural modules. The TriTrusses and their assembly configuration were developed for an in-space assembled telescope conceptual design. The tests presented here were performed with a 1:2.8 dimensionally scaled version of the Tri-Trusses. Robot trajectories were generated autonomously using a sample-based motion planner and an a-priori worksite model. The test results verify the assembly concept of operations as well as the software requirements for the Grapple Tool. While the Grapple Tool used in the tests was designed for the 1:2.8 scale Tri-Trusses, it has the same actuators, software, and computation architecture as the version designed for the full scale structure. The test operations consist of picking up two TriTrusses from their stowed locations and joining them to a third TriTruss mounted on a test stand and joining them to each other. This constitutes the first three modules of the in-space assembled telescope conceptual design. The paper presents the robot behavioral architecture, the generated trajectories commanded, the actual trajectories of the robot, and actuator performance of the Grapple Tool.

test↗
NASA NTRSDate not supplied

Test Results for Autonomous Assembly of Modular Space Structures

This paper presents test results for autonomous assembly of a modular space structure. A Universal Robots UR10e manipulator with a custom end-effector, known as the Grapple Tool, was used to join TriTruss structural modules. The TriTrusses and their assembly configuration were developed for an in-space assembled telescope conceptual design. The tests presented here were performed with a 1:2.8 dimensionally scaled version of the Tri-Trusses. Robot trajectories were generated autonomously using a sample-based motion planner and an a-priori worksite model. The test results verify the assembly concept of operations as well as the software requirements for the Grapple Tool. While the Grapple Tool used in the tests was designed for the 1:2.8 scale Tri-Trusses, it has the same actuators, software, and computation architecture as the version designed for the full scale structure. The test operations consist of picking up two TriTrusses from their stowed locations and joining them to a third TriTruss mounted on a test stand and joining them to each other. This constitutes the first three modules of the in-space assembled telescope conceptual design. The paper presents the robot behavioral architecture, the generated trajectories commanded, the actual trajectories of the robot, and actuator performance of the Grapple Tool.

test↗
NASA NTRS2024

Tall Lunar Tower Ground Demonstration

Time lapse of the Tall Lunar Tower (TLT) Ground EDU Demonstration performed at the Langley Research Center. The demonstration focused on using commercial off-the-shelf robotic manipulator arms with specialized end-effectors to place and join components in a jigging and lifting frame. The frame allows the assembly of a tower by the 6 degree-of-freedom manipulator arms in a work cell configuration by lifting the completed tower segments upward to allow new tower segments to be appended to the bottom of the structure. The demonstration took place from September 28th to 30th 2023.

Tall Lunar Tower↗
DOE OSTI2021

Large-scale continuous carbon/glass fiber additive-compression molded composites

Additive Manufacturing (AM) or 3-D printing has advanced from small-scale desktop printers to large-scale printers. Most of the present large-scale printers utilize feedstock materials in the form of pellets to create composite structures. To create structurally robust composite parts, reinforcements in the form of short fibers (carbon or glass) are often used to impart mechanical properties to the printed parts. However, poor mechanical properties in Z-direction and high porosity of pellets-based printed composites compared to composite manufactured using traditional methods are serious concerns. The authors report a combined approach in the present work, where fiber reinforced composites are printed with a high-throughput continuous fiber deposition method followed by a secondary compression molding process. A specially designed end-effector mounted on a robotic arm is used to print composite preforms. Continuous comingled fibers (Thermofiber 12K CF-PA12, Thermofiber 12K S2-PA12, and Hybrid Thermofiber 12K CF-PA12+PEEK PA6) embedded in the thermoplastic nylon matrix are printed to create composite preform plaques. The printed preforms were further compression molded (CM) using a hydraulic hot-press to create highly consolidated composite parts. The mechanical properties of the continuous fiber composites produced by this combined approach are improved significantly due to the highly aligned continuous fibers and reduced porosity. Flexural strength, flexural modulus, and tensile modulus of AM-CM Thermofiber 12K CF-PA12 UD sample were 615.37 MPa, 75.65 GPa, and 122.23 GPa, respectively.

Kumar, Vipin↗
DOE OSTI2024

Robotics for Systems Integration in Buildings - Pilot Study of Viable Approaches to Install Hygrothermal and Rigid Electrical Systems: Preprint

The Industrialized Construction Innovation (ICI) team at the National Renewable Energy Laboratory (NREL) has been exploring the use of robotics to integrate hygrothermal, mechanical, electrical, and plumbing systems in prefabricated building assemblies (offsite construction) and 3D Printed buildings (onsite construction). Such multi-system integration tasks often require specialized robots and custom end-effectors for handling a range of rigid and non-rigid building components. This paper begins with a brief overview of the current state of robotics in construction, followed by a pilot study exploring the use of robotics to integrate a simple prototype multi-trade wall assembly composed of structural studs, hygrothermal layer, wall finishing, and electrical fixtures. The study was funded by the Department of Energy's (DOE) Advanced Materials and Manufacturing Technologies Office (AMMTO). Insights about the implementation of design for manufacturing and assembly (DfMA) principles in designing the prototype wall for robotic assembly, and selection of appropriate robotic end effector hardware for handling these components are included. Detailed comparison of computational toolpath simulations of the robotic assembly process and real-life demonstration of the same is presented. Finally, limitations and lessons learned from this study along with future research recommendations for robotic assembly of more complex multi-trade assemblies, including potential scenarios such as robotic outfitting of facilities in extra-terrestrial environments is included.

advanced manufacturing↗
DOE OSTI2024

Robotics for Systems Integration in Buildings: Pilot Study of Viable Approaches to Install Hygrothermal and Rigid Electrical Systems

The Industrialized Construction Innovation (ICI) team at the National Renewable Energy Laboratory (NREL) has been exploring the use of robotics to integrate hygrothermal, mechanical, electrical, and plumbing systems in prefabricated building assemblies (off-site construction) and 3D-printed buildings (on-site construction). Such multisystem integration tasks often require specialized robots and custom end effectors to handle a range of rigid and nonrigid building components. This paper begins with a brief overview of the current state of robotics in construction, followed by a pilot study exploring the use of robotics to integrate a simple prototype multitrade wall assembly composed of structural studs, hygrothermal layer, wall finishing, and electrical fixtures. The study was funded by the US Department of Energy's (DOE's) Advanced Materials and Manufacturing Technologies Office (AMMTO). Insights about the implementation of design for manufacturing and assembly (DfMA) principles in designing the prototype wall for robotic assembly, and selection of appropriate robotic end-effector hardware to handle these components are included. Detailed comparison of computational toolpath simulations of the robotic assembly process and real-life demonstration of the same are presented. Finally, limitations and lessons learned from this study are included, along with future research recommendations for robotic assembly of more complex multitrade assemblies, including potential scenarios such as robotic outfitting of facilities in extraterrestrial environments.

advanced manufacturing↗
DOE OSTI2026

Autonomous Coupler Alignment Using Position-Based Visual Servoing in a ROS 2 Framework

As robotic arms are becoming increasingly common alongside humans as collaborative robots, their high precision in motion enables tasks to be performed at significantly higher speeds with reduced disruption in the environment. The Fermi National Accelerator Laboratory is exploring this application by incorporating a UR16e from Universal Robots in a cleanroom setting during assembly of couplers to superconducting radio frequency cavities as part of the PIP-II project. The goal of the robotic assembly process is to precisely position the UR16e robot so that the coupler flange, mounted on the robot’s end-effector, is accurately aligned with and pressed against the cavity flange, requiring only final fastening by a lab technician. This thesis builds upon an initial system in which the robotic process was limited to the alignment phase using position-based visual servoing with an eye-in-hand camera to only align the coupler to the cavity with an offset distance. The objective of this thesis is to further advance autonomous robotic assembly by extending the process. To this end, the entire software framework was reconstructed, as the previous development environment posed significant challenges in modifying the software and adapting to hardware changes. The main contributions of this thesis are as follows: (i) a modular and scalable software framework based on ROS~2 was developed to facilitate performance expansion and interchangeability of software and hardware components; (ii) the desired alignment position for position-based visual servoing was parameterized to enable flexible configuration; and (iii) a methodology was developed to close the offset distance between the coupler and cavity utilizing the internal force-torque sensing capability of the UR16e, as visual feedback is not available during the offset-closing phase. The proposed autonomous robotic assembly reduces assembly time and technician involvement, thereby minimizing the risk of airborne particulate contamination, which is essential in the cleanroom setting. Moreover, the ROS~2-based framework provides a foundation for further expansion and continued advancement of robotic automation in Fermilab.

Giffen, Nickolas [Northern Illinois U.]↗