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At least 217 records · Page 12

Utilization of the NASA Robonaut as a Surgical Avatar in Telemedicine

The concept of teleoperated robotic surgery is not new; however, most of the work to date has utilized specialized robots designed for specific set of surgeries. This activity explores the use of a humanoid robot to perform surgical procedures using the same hand held instruments that a human surgeon employs. For this effort, the tele-operated Robonaut (R2) was selected due to its dexterity, its ability to perform a wide range of tasks, and its adaptability to changing environments. To evaluate this concept, a series of challenges was designed with the goal of assessing the feasibility of utilizing Robonaut as a telemedicine based surgical avatar.

Dean, Marc↗

Anthropomorphic dual-arm space telemanipulation system

Dexterous dual-arm manipulations are feasible with the system described and illustrated in the paper. The structure is based on an extensible host arm that carries the dual-arm robot which comprises two 7-DOF arms each of which includes a hand with a thumb and three fingers with 4 DOF each. Joint compliance can be stiffened to any level, and the operator uses arm harnesses and gloves to utilize the robotics in an anthropomorphic fashion. The configuration eliminates coordinate-transformation computations, and the system is found to achieve a control-frequency rate of 1000 Hz for its direct man/machine interfaces based on fiber-optic cables. The electronics control for the system utilizes a sensory system consisting of force, position, and compliance sensors. The robotics system is expected to be a user-friendly device that permits assembly, repair, tethering, and other complex mechanical operations.

Jau, Bruno M.↗

Manipulator arm design for the Extravehicular Teleoperator Assist Robot (ETAR): Applications on the space station

The preliminary conceptual design of a new teleoperator robot manipulator system for space station maintenance missions has been completed. The system consists of a unique pair of arms that is part of a master-slave, force-reflecting servomanipulator. This design allows greater dexterity and greater volume coverage than that available in current designs and concepts. The teleoperator manipulator is specifically designed for space applications and is a valuable extension of the current state-of-the-art earthbound manipulators marketed today. The manipulator and its potential application on the space station are described.

Clarke, Margaret M.↗

An inverse kinematics algorithm for a highly redundant variable-geometry-truss manipulator

A new class of robotic arm consists of a periodic sequence of truss substructures, each of which has several variable-length members. Such variable-geometry-truss manipulator (VGTMs) are inherently highly redundant and promise a significant increase in dexterity over conventional anthropomorphic manipulators. This dexterity may be exploited for both obstacle avoidance and controlled deployment in complex workspaces. The inverse kinematics problem for such unorthodox manipulators, however, becomes complex because of the large number of degrees of freedom, and conventional solutions to the inverse kinematics problem become inefficient because of the high degree of redundancy. A solution is presented to this problem based on a spline-like reference curve for the manipulator's shape. Such an approach has a number of advantages: (1) direct, intuitive manipulation of shape; (2) reduced calculation time; and (3) direct control over the effective degree of redundancy of the manipulator. Furthermore, although the algorithm was developed primarily for variable-geometry-truss manipulators, it is general enough for application to a number of manipulator designs.

Naccarato, Frank↗

Assembling, maintaining and servicing Space Station

The assembly, maintenance, and servicing of the Space Station and its facilities are discussed. The tools and facilities required for the assembly, maintenance, and servicing of the Station are described; the ground and transportation infrastructures needed for the Space Station are examined. The roles of automation and robotics in reducing the EVAs of the crew, minimizing disturbances to the Space Station environment, and enhancing user friendliness are investigated. Servicing/maintenance tasks are categorized based on: (1) urgency, (2) location of servicing/maintenance, (3) environmental control, (4) dexterity, (5) transportation, (6) crew interactions, (7) equipment interactions, and (8) Space Station servicing architecture. An example of a servicing mission by the Space Station for the Hubble Space Telescope is presented.

Doetsch, K. H.↗

Robonaut 2 (R2) Overview

This slide presentation reviews the development and uses of the second robot designed to work in space. The presentation reviews the motivation for developing Robonaut, the cooperative commercial relationship with General Motors, the evolution design of Robonaut Robonaut 2 improvements over the first robonaut (R1), Robonaut 2's hand dexterity, finger impedance control, tactile system, finger haptics, arm control, strength, neck movement and head sensors, human interaction, and the controller. Also the plans for use on board the International Space Station are reviewed. The patent for the Phalange Tactile Load Cell is included.

Diftler, Myron↗

High-capacity ATHLETE Offloader Mobility Constructor Concept for Human Surface Exploration

Using cross-cabled, winch-tendon four-bar frames, a new Artemis-class ATHLETE system is a multi-limbed robotic mobility platform that is designed for surface traverse, precision placement, and offloading of heavy habitats and other large human exploration payloads from high-decked landers. Building upon lessons learned from the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) robotic mobility system developed for Constellation Lunar Surface Systems and Evolvable Mars Campaign, a high-capacity articulated crane / lift vehicle concept has been devised that would be equipped with multi-limb six-degree-of-freedom dexterity for a variety of tasks supporting planetary surface human exploration missions and outposts. The Artemis-class ATHLETE vehicle would use any combination of three to six wheel-onlimb combinations to provide a wide “outrigger” stance to transfer loads from a high center-of-gravity on sloped terrain to low stable carry configurations for long-distance traverses, and be capable of precision docking of payloads to previously positioned elements. The new vehicle concept improves upon previous Constellation-class ATHLETE versions by allowing modular hot-swapping of individual limbs to improve maintenance and flexibility. The extreme-capacity independent limbs can individually function as single cranes, and can be delivered separately via multiple lander manifests for later congregation into self-driving “Tri-ATHLETE” vehicles after delivery to the surface. This paper provides mission architecture targets and vehicle masses for stepped payload capacity values in Earth, Mars, and Lunar gravity environments, and discusses a variety of swappable tools, including wheeled mobility attachments, grippers, excavation tools, repair fixtures, ISRU extraction, winches, block & tackle rigging combinations, 3D printheads, and construction aids.

Wilcox, Brian↗

Control algorithm implementation for a redundant degree of freedom manipulator

This project's purpose is to develop and implement control algorithms for a kinematically redundant robotic manipulator. The manipulator is being developed concurrently by Odetics Inc., under internal research and development funding. This SBIR contract supports algorithm conception, development, and simulation, as well as software implementation and integration with the manipulator hardware. The Odetics Dexterous Manipulator is a lightweight, high strength, modular manipulator being developed for space and commercial applications. It has seven fully active degrees of freedom, is electrically powered, and is fully operational in 1 G. The manipulator consists of five self-contained modules. These modules join via simple quick-disconnect couplings and self-mating connectors which allow rapid assembly/disassembly for reconfiguration, transport, or servicing. Each joint incorporates a unique drive train design which provides zero backlash operation, is insensitive to wear, and is single fault tolerant to motor or servo amplifier failure. The sensing system is also designed to be single fault tolerant. Although the initial prototype is not space qualified, the design is well-suited to meeting space qualification requirements. The control algorithm design approach is to develop a hierarchical system with well defined access and interfaces at each level. The high level endpoint/configuration control algorithm transforms manipulator endpoint position/orientation commands to joint angle commands, providing task space motion. At the same time, the kinematic redundancy is resolved by controlling the configuration (pose) of the manipulator, using several different optimizing criteria. The center level of the hierarchy servos the joints to their commanded trajectories using both linear feedback and model-based nonlinear control techniques. The lowest control level uses sensed joint torque to close torque servo loops, with the goal of improving the manipulator dynamic behavior. The control algorithms are subjected to a dynamic simulation before implementation.

Cohan, Steve↗

Active Compliance And Damping In Telemanipulator Control

Experimental telemanipulator system of force-reflecting-hand-controller type provides for active compliance and damping in remote, robotic manipulator hand. Distributed-computing and -control system for research in various combinations of force-reflecting and active-compliance control regimes. Shared compliance control implemented by low-pass-filtered force/torque feedback. Variable simulated springs and shock absorbers soften collisions and increase dexterity.

Kim, Won S.↗

A prototype supervised intelligent robot for helping astronauts

The development status is described of a prototype supervised intelligent robot for space application for purposes of (1) helping the crew of a spacecraft such as the Space Station with various tasks such as holding objects and retrieving/replacing tools and other objects from/into storage, and for purposes of (2) retrieving detached objects, such as equipment or crew, that have become separated from their spacecraft. In addition to this set of tasks in this low Earth orbiting spacecraft environment, it is argued that certain aspects of the technology can be viewed as generic in approach, thereby offering insight into intelligent robots for other tasks and environments. Also described are characterization results on the usable reduced gravity environment in an aircraft flying parabolas (to simulate weightlessness) and results on hardware performance there. These results show it is feasible to use that environment for evaluative testing of dexterous grasping based on real-time visual sensing of freely rotating and translating objects.

Erickson, J. D.↗

Human-Robot Control Strategies for the NASA/DARPA Robonaut

The Robotic Systems Technology Branch at the NASA Johnson Space Center (JSC) is currently developing robot systems to reduce the Extra-Vehicular Activity (EVA) and planetary exploration burden on astronauts. One such system, Robonaut, is capable of interfacing with external Space Station systems that currently have only human interfaces. Robonaut is human scale, anthropomorphic, and designed to approach the dexterity of a space-suited astronaut. Robonaut can perform numerous human rated tasks, including actuating tether hooks, manipulating flexible materials, soldering wires, grasping handrails to move along space station mockups, and mating connectors. More recently, developments in autonomous control and perception for Robonaut have enabled dexterous, real-time man-machine interaction. Robonaut is now capable of acting as a practical autonomous assistant to the human, providing and accepting tools by reacting to body language. A versatile, vision-based algorithm for matching range silhouettes is used for monitoring human activity as well as estimating tool pose.

Diftler, M. A.↗

The astronaut and the banana peel: An EVA retriever scenario

To prepare for the problem of accidents in Space Station activities, the Extravehicular Activity Retriever (EVAR) robot is being constructed, whose purpose is to retrieve astronauts and tools that float free of the Space Station. Advanced Decision Systems is at the beginning of a project to develop research software capable of guiding EVAR through the retrieval process. This involves addressing problems in machine vision, dexterous manipulation, real time construction of programs via speech input, and reactive execution of plans despite the mishaps and unexpected conditions that arise in uncontrolled domains. The problem analysis phase of this work is presented. An EVAR scenario is used to elucidate major domain and technical problems. An overview of the technical approach to prototyping an EVAR system is also presented.

Shapiro, Daniel G.↗

Telerobotic capabilities for space operations

This paper presents a summary of tests involving either pure telerobotics, or telerobots in conjunction with extravehicular activity, applied to some of the servicing tasks of the Hubble Space Telescope (HST). This research was conducted in a neutral buoyancy environment, using the high fidelity mockup used for astronaut crew training, along with two telerobots developed in the Space Systems Laboratory. These tests showed that current telerobots are capable of a limited subset of tasks required for EVA servicing of HST, and that specific developments in robotic capability are required, particularly in high torque output and positioning in constrained volumes, before the telerobotic systems are capable replacements to EVA. A more immediately promising application is the use of telerobots to enhance and extend the EVA capabilities, by acting as 'assistants' to the EVA crewmen performing the dexterous and high-force tasks.

Akin, David L.↗

Mobile Remote Manipulator

Turret, roll arm, and trolley enhance manipulator dexterity. Remote manipulator moves on trolley base along structure. Roll-axis arm positions manipulator arm so it can extend end effector under structure. Yaw-axis rotation gives added reach to arm above structure. Designed for handling, inspecting, and maintaining modules of space station. Manipulators having such capabilities useful on Earth; robots in manufacturing, erection of large structures, or performing complicated tasks in hazardous locations.

Coryell, S.↗

Making ROBONAUT an Intelligent Assistant for Humans

This presentation is an overview of the Robonaut project. Robonaut is a humanoid robot designed by the Automation, Robotics, and Simulation Division at NASA's Johnson Space Center. The Robonaut project seeks to develop and demonstrate a robotic system that can function as an EVA astronaut equivalent. Robonaut jumps generations ahead by eliminating the robotic scars (e.g., special robotic grapples and targets) and specialized robotic tools of traditional on-orbit robotics. However, it still keeps the human operator in the control loop through its telepresence control system. Robonaut is being designed for "EVA" tasks, i.e., those that were not specifically designed for robots. Our challenge is to build machines that can help humans work and explore in space. Working side by side with humans, or going where the risks are too great for people, machines like Robonaut will expand our ability for construction and discovery. Central to that effort is a capability we call dexterous manipulation, embodied by an ability to use ones hand to do work, and our challenge is to build machines with dexterity that exceeds that of a suited astronaut.

Savely, Robert T.↗

Using the ISS as a Testbed to Prepare for the Next Generation of Space-Based Telescopes

The ISS provides a unique opportunity to develop the technologies and operational capabilities necessary to assemble future large space telescopes that may be used to investigate planetary systems around neighboring stars. Assembling telescopes in space is a paradigm-shifting approach to space astronomy. Using the ISS as a testbed will reduce the technical risks of implementing this major scientific facility, such as laser metrology and wavefront sensing and control (WFSC). The Optical Testbed and Integration on ISS eXperiment (OpTIIX) will demonstrate the robotic assembly of major components, including the primary and secondary mirrors, to mechanical tolerances using existing ISS infrastructure, and the alignment of the optical elements to a diffraction-limited optical system in space. Assembling the optical system and removing and replacing components via existing ISS capabilities, such as the Special Purpose Dexterous Manipulator (SPDM) or the ISS flight crew, allows for future experimentation and repair, if necessary. First flight on ISS for OpTIIX, a small 1.5 meter optical telescope, is planned for 2015. In addition to demonstration of key risk-retiring technologies, the OpTIIX program includes a public outreach program to show the broad value of ISS utilization.

Ess, Kim↗

Learning Grasp Context Distinctions that Generalize

Control-based approaches to grasp synthesis create grasping behavior by sequencing and combining control primitives. In the absence of any other structure, these approaches must evaluate a large number of feasible control sequences as a function of object shape, object pose, and task. This work explores a new approach to grasp synthesis that limits consideration to variations on a generalized localize-reach-grasp control policy. A new learning algorithm, known as schema structured learning, is used to learn which instantiations of the generalized policy are most likely to lead to a successful grasp in different problem contexts. Two experiments are described where Dexter, a bimanual upper torso, learns to select an appropriate grasp strategy as a function of object eccentricity and orientation. In addition, it is shown that grasp skills learned in this way can generalize to new objects. Results are presented showing that after learning how to grasp a small, representative set of objects, the robot's performance quantitatively improves for similar objects that it has not experienced before.

Platt, Robert↗