2.2.3 Attached Servicers

This segment of the program is focussed on the development of space robotics for on-orbit servicing by systems attached to supporting structures such as the Space Shuttle or Space Station. The purpose of this segment of the program is to focus the development of component technologies into applications and environments which will demonstrate their utility and additional capability when incorporated into operational systems. These technologies include virtual reality telepresence, advanced display technologies, proximity sensing for perception technologies, and robotic flaw detection. The target applications include such tasks as repair of small satellites, ground-based control of robotic servicers, and servicing of external space platform payloads. Each of these areas have been identified by the potential space robotics user community as applications where space robotics will be necessary to satisfy their planned requirements. This user community includes Space Station Alpha, Mission to Planet Earth, and the Space Transportation System.

Remote Surface Inspection

Distributed Space Telerobotics

Unified Operator Interface

Telepresence / Exoskeleton

ISSA Telerobotic Maintenance Technology Transfer

Technology Transfer Roadmap Details

Remote Surface Inspection

Complex space missions require routine and unscheduled inspection for safe operation. The Jet Propulsion Laboratory is conducting a research and development program to develop supervised inspection techniques for tedious tasks as an aid to the operator. The telerobotic system would perform inspection relative to a given reference (e. g., the status of the facility at the time of the last inspection) and alert the operator to potential anomalies for verification and action. One example might be for the inspection of truss struts for micrometeoroid damage and visible cracks on thermal radiator surfaces. Simulation of realistic dynamic lighting conditions is included. In addition, configuration control of manipulators with redundant degrees of freedom pioneered by JPL has been implemented to assure dexterous manipulation near complete structures.

The baseline inspection task is to teleoperate a robotic arm which carries a pair of mini-wrist cameras. The operator uses a pair of 3-DOF joysticks and can control the lighting to better view the scene. Additional cameras with pan/tilt zoom/focus control are controlled by the operator to observe the arm's motion and to inspect objects which are far away from the arms. A local remote architecture is employed so that space and time distances can be effectively treated. Multi-sensor based inspection of gas leak, temperature, and damage is conducted. Subsequently, inspection tasks requiring contact such as Eddy current based crack detection is performed.

Focus and Directions:

FY 94 Develop capability to perform inspection tasks requiring contact with environment. Detect cracks remotely via a telerobot. Crack length 0.08 inches, depth 0.01 inches, and width 0.007 inches. Develop whole arm proximity detection system and show safe operation within 1 foot of any unknown object.

FY 95 Transfer operator interface technology to JSC and perform multi-sensor inspection including Eddy current based crack detection in RSI lab from JSC. Perform inspection tasks in hard-to-reach areas. Show capability to enter openings as small as 6 inches and inspect objects two feet deep inside the opening. Using whole arm proximity sensing, show capability to safely navigate in cluttered environment where the CAD data is missing objects. Document timeline and capabilities comparison versus conventional teleoperation for inspection.

Point of Contact:
Paul Backes
(818)354-3850
Paul.G.Backes@jpl.nasa.gov

Distributed Space Telerobotics

The goal of this project is to improve flexibility of ground-based robot command and control, and within this area, foster international cooperation in space robotics R&D. The NASA technology objectives, which address future needs of Space Station and STS robotic operations, are:

Intelligent Viewing Control (IVC): provide an operator interface for reliable and efficient 3-D perception in limited-view, limited-access work scenarios (Operations goal is computer planning and sequencing of multiple camera views, including calibrated 3-D graphics for "hard to see" areas, capable of reducing conventional task viewing-to-manipulation time by 50%)

Intelligent Motion Control (IMC): provide an operator interface for control of dexterous robot motion under extended time delay, including work in uncertain task scenarios (Operations goal is teleprogrammed control up to 10 seconds delay, including proximity-and-contact motions in tasks which are a priori known to only 5-10% geometric accuracy)

Note this project currently cooperates with the MITI Electrotechnical Laboratory (ETL) of Japan, in an ongoing set of trans-Pacific operations experiments and feasibility demonstrations. NASA's experimentation emphasizes platform servicing, and MITI emphasizes on-orbit assembly.

Focus and Directions:

FY '94 Develop a baseline IVC capability and IMC remote controller functions and interfaces. Demonstrate reciprocal ETL-to-JPL robotic operations.

FY '95 Verify IVC capability in trans-Pacific JPL->ETL dexterous space assembly experiments based on a truss-based deployment of solar-powered ORU [Level 1]. Develop an operator interface for the IMC remote controller.

FY '96 Generalize IVC to include on-line task modeling & semi-autonomous calibration and develop teleprogrammed operations incorporating "behavior-based" IMC. Perform a trans-Pacific ETL->JPL servicing task demonstration with obstructed ORU visualization, robotic access and maintenance [Level 1]. Model Ranger system and apply IVC to Ranger application in simulation.

FY '97 Demonstrate unpredictable event handling (where the operator has only partial prior task models), based on an integrated use of the IVC and IMC interfaces [Level 1]. Deliver IVC capability to Ranger program.

Point of Contact:
Paul Backes
(818)354-3850
Paul.G.Backes@jpl.nasa.gov

Unified Operator Interface

This project develops an operator workstation and enabling technologies for robust ground-to-orbit telerobot control. Such development is essential to space platform maintenance that minimizes use of valuable astronaut EVA/IVA time. Space Station external inspection and ORU changeout are representative tasks that require more flexible robotic operations. Per a recent NASA SSF/OSAT Robotics Technology Study, such maintenance can be ameliorated via ground control of MSC/SPDM, allowing both earlier permanent SS habitation and increased science return; related opportunities also exist for STS robotics upgrades. The major project deliverable is a common architecture workstation that supports both other TRIWG technology projects (RSI, DST, JSC ARMSS, etc.) and planned NASA flight robotics applications (SS, DOSS, etc.). Building on Telerobotics Program resources for remote viewing, semi-automated inspection, 3-D graphics, and remote manual & supervisory controls, the project implements a ground operatorŐs environment with consistent user interface formats and protocols across multiple applications -- both technology functions and operations experience are thus made reusable. Specifically, the ground workstation includes interactive 3-D task modeling & description utilities, preview simulation, collision management, graphically programmed control, preview simulation & predictive teleoperation, teleprogrammed time-delay operations, and semi-automated viewing and inspection, and thus flexibly spans partially-to-well-structured operations. These integrated functions will be realistically demonstrated, first in physically distributed lab operations at JPL, and subsequently in coordinated inspection-&-manipulation and contingency tasking scenarios between JPL and JSC.

In FY 1995, this activity has been incorporated into the Lander Manipulation task.

Point of Contact:
Antal Bejczy
(818) 354-4568
bejczy@telerobotics.jpl.nasa.gov

Telepresence / Exoskeleton

This project augments telemanipulation capabilities through the development and evaluation of a unique force-reflecting master-slave exoskeleton anthropomorphic (human-like) arm-hand system, in two development phases, with emphasis on the use of EVA-rated tools and on minimum training requirements. The first and ongoing development phase is for a single arm-hand system, and the second phase (to be pursued later, starting in FY '96) is for a "dual-arm/hand" system. The FY '91 and FY '92 efforts produced a seven d.o.f. master arm with a full drive system and the engineering design of the lower arm/wrist of the slave arm. The FY '93 effort produced the slave lower arm/wrist integrated with a four-finger slave hand, and configured it in a "terminus control mode." In this control mode, the lower slave arm/wrist/hand subsystem is mounted to an existing PUMA 560 six d.o.f. industrial robot arm, and the four-finger force-reflecting master glove is mounted to a general purpose six d.o.f. force-reflecting hand controller.

In FY 1995, this activity has been incorporated into the Remote Geologist task.

Point of Contact:
Antal Bejczy
(412) 354-4568
bejczy@telerobotics.jpl.nasa.gov

ISSA Telerobotic Maintenance Technology Transfer

The objectives of this program element are to provide a robotic emulation of the Canadian SPDM and perform candidate Space Station maintenance experiments. This system will provide the capability to assess Space Station compatibility with planned robotic maintenance. Through a high fidelity model of this type, an accurate assessment of SSA robotic maintenance capabilities can be achieved. From this information, critical design inputs can be made early in the development cycle.

Developing a hardware emulation of the SPDM will provide early design assessments of SSA components suited for robotic maintenance. The research conducted by this task utilizes the Automated Robotic Maintenance of Space Station (ARMSS) testbed facility at JSC. The ARMSS is the primary technology transfer mechanism to move program technology to the Space Station program.

Focus and Directions:

FY94 Transfer technology remote surface inspection technology from JPL and perform Space Station inspection scenarios.

FY94 Transfer flat target technology from JPL and evaluate maintenance timelines using this new targeting technology affixed to the ORU box.

FY94 Transfer the Capaciflector technology from GSFC for evaluation in performing the mate of the ORU subcarrier with the Integrated Program Interface (IPI).

FY95 Perfom surface inspection scenarios in ARMSS with astronaut operators for user evaluations.

FY95 Transfer first generation technology product from JPL Unified Operator Interface task into ARMSS and perform crew evaluations.

FY95 Transfer robot motion path planner from LaRC that was developed as part of the Automated Truss Assembly task into the ARMSS testbed to provide collision free robot motion around the pre-integrated truss element.

FY95 Perform second generation Capaciflector tests with improved operator interface. Evaluations will be performed by astronaut personnel to provide user feedback for further enhancement to this technology.

Points of Contact:
Charles Price
(713)483-1523
crprice@aio.jsc.nasa.gov

Samad Hayati
(412) 354-8273
hayati@telerobotics.jpl.nasa.gov