2,519 research outputs found
Dynamics, control and sensor issues pertinent to robotic hands for the EVA retriever system
Basic dynamics, sensor, control, and related artificial intelligence issues pertinent to smart robotic hands for the Extra Vehicular Activity (EVA) Retriever system are summarized and discussed. These smart hands are to be used as end effectors on arms attached to manned maneuvering units (MMU). The Retriever robotic systems comprised of MMU, arm and smart hands, are being developed to aid crewmen in the performance of routine EVA tasks including tool and object retrieval. The ultimate goal is to enhance the effectiveness of EVA crewmen
GRASP News Volume 9, Number 1
A report of the General Robotics and Active Sensory Perception (GRASP) Laboratory
\u3cem\u3eGRASP News\u3c/em\u3e: Volume 9, Number 1
The past year at the GRASP Lab has been an exciting and productive period. As always, innovation and technical advancement arising from past research has lead to unexpected questions and fertile areas for new research. New robots, new mobile platforms, new sensors and cameras, and new personnel have all contributed to the breathtaking pace of the change. Perhaps the most significant change is the trend towards multi-disciplinary projects, most notable the multi-agent project (see inside for details on this, and all the other new and on-going projects). This issue of GRASP News covers the developments for the year 1992 and the first quarter of 1993
\u3cem\u3eGRASP News\u3c/em\u3e, Volume 8, Number 1
A report of the General Robotics and Active Sensory Perception (GRASP) Laboratory. Edited by Thomas Lindsay
Nonterrestrial utilization of materials: Automated space manufacturing facility
Four areas related to the nonterrestrial use of materials are included: (1) material resources needed for feedstock in an orbital manufacturing facility, (2) required initial components of a nonterrestrial manufacturing facility, (3) growth and productive capability of such a facility, and (4) automation and robotics requirements of the facility
Space Exploration Robotic Systems - Orbital Manipulation Mechanisms
In the future, orbital space robots will assist humans in space by constructing
and maintaining space modules and structures. Robotic manipulators will play
essential roles in orbital operations. This work is devoted to the implemented
designs of two different orbital manipulation mechanical grippers developed
in collaboration with Thales Alenia Space Italy and NASA Jet Propulsion
Laboratory – California Institute of Technology.
The consensus to a study phase for an IXV (Intermediate eXperimental
Vehicle) successor, a preoperational vehicle called SPACE RIDER (Space Rider
Reusable Integrated Demonstrator for European Return), has been recently
enlarged, as approved during last EU Ministerial Council. One of the main
project task consists in developing SPACE RIDER to conduct on orbit servicing
activity with no docking. SPACE RIDER would be provided with a robotic
manipulator system (arm and gripper) able to transfer cargos, such as scientific
payloads, from low Earth orbiting platforms to SPACE RIDER cargo bay.
The platform is a part of a space tug designed to move small satellites and
other payloads from Low Earth Orbit (LEO) to Geosynchronous Equatorial
Orbit (GEO) and viceversa. The assumed housing cargo bay requirements
in terms of volume (<100l) and mass (<50kg) combined with the required
overall arm dimensions (4m length), and mass of the cargo (5-30kg) force
to developing an innovative robotic manipulator with the task-oriented end
effector. It results in a seven degree-of-freedom arm to ensure a high degree
of dexterity and a dedicate end-effector designed to grasp the cargo interface.
The gripper concept developed consists in a multi-finger hand able to lock both
translational and rotational cargo degrees of freedom through an innovative
underactuation strategy to limit its mass and volume. A configuration study
on the cargo handle interface was performed together with some computer
aided design models and multibody analysis of the whole system to prove its feasibility. Finally, the concept of system control architecture, the test report
and the gripper structural analysis were defined.
In order to be able to accurately analyze a sample of Martian soil and to
determine if life was present on the red planet, a lot of mission concepts have
been formulating to reach Mars and to bring back a terrain sample. NASA
JPL has been studying such mission concepts for many years. This concept is
made up of three intermediate mission accomplishments. Mars 2020 is the first
mission envisioned to collect the terrain sample and to seal it in sample tubes.
These sealed sample tubes could be inserted in a spherical envelope named
Orbiting Sample (OS). A Mars Ascent Vehicle (MAV) is the notional rocket
designed to bring this sample off Mars, and a Rendezvous Orbiting Capture
System (ROCS) is the mission conceived to bring this sample back to Earth
through the Earth Entry Vehicle (EEV). MOSTT is the technical work study
to create new concepts able to capture and reorient an OS. This maneuver is
particularly important because we do not know an OS incoming orientation and
we need to be able to capture, to reorient it (2 rotational degrees of freedom),
and to retain an OS (3 translational degrees of freedom and 2 rotational ones).
Planetary protection requirements generate a need to enclose an OS in two shells
and to seal it through a process called Break-The-Chain (BTC). Considering
the EEV would return back to Earth, the tubes orientation and position have
to be known in detail to prevent any possible damage during the Earth hard
landing (acceleration of ∼1300g). Tests and analysis report that in order for the
hermetic seals of the sample tubes to survive the impact, they should be located
above an OS equator. Due to other system uncertainties an OS presents the
potential requirement to be properly reoriented before being inserted inside the
EEV. Planetary protection issues and landing safety are critical mission points
and provide potential strict requirements to MOSTT system configuration. This
task deals with the concept, design, and testbed realization of an innovative
electro-mechanical system to reorient an OS consistent with all the necessary
potential requirements. One of these electro-mechanical systems consists of a
controlled-motorized wiper that explores all an OS surface until it engages with
a pin on an OS surface and brings it to the final home location reorienting an
OS. This mechanism is expected to be robust to the incoming OS orientation
and to reorient it to the desired position using only one degree of freedom
rotational actuator
COBE's search for structure in the Big Bang
The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle
Research and Technology
Johnson Space Center (JSC) accomplishments in new and advanced concepts during 1989 are highlighted. This year, reports are grouped in sections, Medical Science, Solar System Sciences, Space Transportation Technology, and Space Systems Technology. Summary sections describing the role of JSC in each program are followed by descriptions of significant tasks. Descriptions are suitable for external consumption, free of technical jargon, and illustrated to increase ease of comprehension
Proceedings of the NASA Conference on Space Telerobotics, volume 3
The theme of the Conference was man-machine collaboration in space. The Conference provided a forum for researchers and engineers to exchange ideas on the research and development required for application of telerobotics technology to the space systems planned for the 1990s and beyond. The Conference: (1) provided a view of current NASA telerobotic research and development; (2) stimulated technical exchange on man-machine systems, manipulator control, machine sensing, machine intelligence, concurrent computation, and system architectures; and (3) identified important unsolved problems of current interest which can be dealt with by future research
Dynamic motion coupling of body movement for input control
Touchless gestures are used for input when touch is unsuitable or unavailable, such as when interacting with displays that are remote, large, public, or when touch is prohibited for hygienic reasons. Traditionally user input is spatially or semantically mapped to system output, however, in the context of touchless gestures these interaction principles suffer from several disadvantages including memorability, fatigue, and ill-defined mappings. This thesis investigates motion correlation as the third interaction principle for touchless gestures, which maps user input to system output based on spatiotemporal matching of reproducible motion. We demonstrate the versatility of motion correlation by using movement as the primary sensing principle, relaxing the restrictions on how a user provides input. Using TraceMatch, a novel computer vision-based system, we show how users can provide effective input through investigation of input performance with different parts of the body, and how users can switch modes of input spontaneously in realistic application scenarios. Secondly, spontaneous spatial coupling shows how motion correlation can bootstrap spatial input, allowing any body movement, or movement of tangible objects, to be appropriated for ad hoc touchless pointing on a per interaction basis. We operationalise the concept in MatchPoint, and demonstrate the unique capabilities through an exploration of the design space with application examples. Finally, we explore how users synchronise with moving targets in the context of motion correlation, revealing how simple harmonic motion leads to better synchronisation. Using the insights gained we explore the robustness of algorithms used for motion correlation, showing how it is possible to successfully detect a user's intent to interact whilst suppressing accidental activations from common spatial and semantic gestures. Finally, we look across our work to distil guidelines for interface design, and further considerations of how motion correlation can be used, both in general and for touchless gestures
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