18th annual conference on manual control.pdf - Acgsc.org

DEXTEROUS MANIPULATOR LABORATORY PROGRAM
Roy E. Olsen
Grumman Aerospace Corp.
Bethpage, N.Y. 11714
ABSTRACT
This paper describes a program currently underway to develop telepresence
systems for the support of spacemissions such as satellite maintenance and
repair. A force-reflecting, dexterous manipulator system is emphasized as the
basis for the development of integrated telepresence systems. Alternate
controllers, control implementations, modified end effectors, and candidate
vision systems will be evaluated to resolve human-machine design issues.
INTRODUCTION
A major consideration being addressed as we enter the Space Shuttle era
concerns the extent of extra-vehicular activity (EVA) to perform tasks in
space versus remotely operated and automated systems. Mission analysis
studies have identified many complex tasks which will be required in the areas
of satellite services and space construction (Ref. i). There are numerous
reasons for strongly favoring remotely operated and automated systems for
certain applications. These reasons include removal of the astronaut from the
vicinity of hazardous operations (such as transferring propellant) and reduction
of the non-productive operational time associated with EVA.
Remote human presence, i.eo, "telepresence", is envisioned as the needed
capability for many tasks because of their low frequency of occurrence and/or
high level of difficulty. Telepresence systems provide the capability to
perform difficult operations with human versatility by providing "natural"
control interfaces, vision, and mechanical arms to the operator.
The evolution of space telepresence systems from the present conceptual
stage to operational flight status will require development along the lines
indicated in Fig. i, starting with ground-based laboratory tests and simulation
and progressing through flight demonstration programs leading to operational
systems° The latter will include orbiter-attached configurations,
space station support versions, and both manned and unmanned free-flying
applications.
Initial studies make it clear that current technology in the fields of
nuclear energy, underwater exploration, and industrial robotics are not
sufficient to meet the needs of space telepresence. Technology and application
issues were identified which require resolution before such systems can
be fully developed. Issues such as the type of controller needed, control
mode, force reflection applicability, working volume, time delay effects,
number of arms, and degrees of freedom must be addressed before operational
systems can be defined.
The key to developing space telepresence technology is to start with
manned dexterous manipulators and evolve the control implementations, vision
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