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Impact of Integrated Vehicle Health Management IVHM)Technologies on Ground Operations for Reusable Launch

Vehicles RLVs) and SpacecraftJack J. Fox

NASA Kennedy Space Centeriack.fou- C3ksc.nasa.gov321-867-2141

B. J. GlassNASA Ames Research Center

[email protected].,Uov650-604-3512

Abstract-Incorporation of Integrated Vehicle HealthManagement (IVHM) technologies into launch vehicle andspacecraft designs offers the potential for significantsavings in operations costs. IVHM has three basicobjectives. First is more autonomous operation in flightand on the ground, which directly translates to reducedworkload on the ground controller team through reductionof raw vehicle data into health summary information.Next is reduced ground processing of reusable vehicles dueto more performance of system health checks in flightrather than back on the ground as well as more automatedground servicing and checkout. Lastly is enhanced vehiclesafety and reliability due to increased capability to monitorsystem health using modem sensing systems inside even theharsh environment of an engine combustion chamber aswell as through prediction of pending failures.The integrated piece of IVHM is the total integration offlight and ground IVHM elements. The three elements offlight IVHM are advanced light weighflow power sensors,extensive real-time data processing and analysis anddistributed data acquisition architecture with high-densitymass storage. The two elements of ground IVHM areevolved control room architectures with advancedapplications and automated ground processing systems.The traditional model of a vehicles instrumentation systemconsists of a distribution of sensors, signal conditioningdevices and multiplexing devices, a complex andcumbersome network of wiring and a centralizedprocessor/recorder. Characteristics of a modem,distributed IVHM instrumentation system include modemsensors such as ultrasonic flow, photonic and MicroElectromechanical Systems based sensors leading tostrategically placed Health Nodes with extensive dataprocessing by system health diagnostic algorithms which intum interface via fiber

U.S. Govemment work not protectedby U.S. copyright.

optic communication with a master processor-recorder.These diagnostic algorithms rely on models of systemstructure and definitions of nominal behavior, incomparison with actual system behavior, to identify andisolate current and predicted future faults. The flightsystem then interfaces with automated ground supportequipment for system servicing and trend analysis.A status of current flight experiments on Space Shuttle,Deep Space-1, X-33, X-34 and X-37 will be presented.

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TABLE OFCONTENTSIntroductionDefinitionsHardware TechnologiesSoftware TechnologiesSummary of Flight ExperimentsConclusionsReferencesBiographies

1. INTRODUCTIONThe impact of IVHM on launch vehicle and spacecraftoperations is in terms of improvements in safetyreliability, maintenance and operations. Safety is enhancedfor the public, astronauts pilots, employees and high-value equipment property on several fronts. IVHMprovides the flight crew and ground with tools for fasteridentification of failures and predicted failures of highcriticality systems and hazards as well as theuncompromising pre-programmed responses having fail-safe features derived through formal risk managementpractices. Probabilities of human errors are reduced. Also,reliability and robustness are improved through full vehicleand ground system IVHM coverage and increasedredundancies. Aircraft-like maintenance will be possiblethrough automated in situ vehicle checkout duringoperation and robust on-board fault isolation andprediction. Ground maintenance will be performed on an

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exception-only basis and will be pre-planned andautomatically adjusted prior to vehicle retum. Operationsin flight and on the ground will be enhanced through moreautonomous operation allowing faster responses with fewerpersonnel. Also, lighter weight vehicles will provideincreased capabilities and margins. Key metrics of IVHMeffectiveness will be a significant reduction in turnaroundtime, decrease in catastrophic unreliability, increase innumber of flights per year, reduction in the variable costper flight, reduction in ground and flight support personneland increased hardware mission life. To reach its fullpotential, IVHM must be designed in from the start of aprogram rather than being an add-on later.National IVHM TeamA national team is developing NASAs IVHM blueprint forthe Advanced Space Transportation Program (ASTP). Theteam is striving for representation from the entire NASAand Department of Defense (DoD) IVHM community fortechnology leveraging across the NASA enterprises ofAeronautics Space Transportation, Earth Science,Human Exploration and Development of Space (HEDS)and Space Science as well as DoD programs. Many morecollaborative projects beyond those described in this paperincluding pathfinder class, trailblazer class and a magneticlevitation launch assist vehicle are planned. IVHM isclearly an enabling technology for NASAs bold missionsin space exploration and aeronautics. IVHM will transformthe critical application areas of autonomous spacecraftrovers, science data understanding, space aviationoperations, maintenance and human exploration of space.(Ref . 1)

2 . DEFINITIONSThe integrated aspect of IVHM is the total integration offlight and ground IVHM elements. Monitoring issometimes used instead of Management and describes thedegree of autonomy in a particular application. There is aspectrum for the degree of autonomy. At one end, anautonomous Management system takes action while atthe other end, a Monitoring system recommends action.The traditional model of a vehicles instrumentation systemconsists of a distribution of sensors, signal conditioningdevices and multiplexing devices, a complex andcumbersome network of wiring and a centralizedprocessor/recorder. Benefits of a modem, distributedIVHM instrumentation system include greatly reducedvolume of wiring, reduced power requirements, reducedvehicle weight, reduced avionics cooling requirements,simplified incorporation of additional sensors and extensivedata processing.

Flight IVHMThe three elements of flight IVHM are advanced lightweightnow power sensors, distributed data acquisitionarchitecture with advanced storage and extensive real-timedistributed data processing. Examples of advanced sensorsinclude highly redundant microhano sensors such as a gridof hundreds of pressure sensors; photonic sensors such asFiber Bragg-Grating (FI3G) sensors for strain, temperatureand hazardous gas detection; wireless sensors such astemperature sensors inside an engine turbine and radiofrequency powered devices; smart sensors that directlycommunicate digitally on a data bus, are regenerative, auto-calibrate and data cross-check for improved accuracy anddata validation and non-intrusive sensors such as clamp-onHall Effect current detection and ultrasonic fluid flowdetection.

Distributed data acquisition architecture with advancedstorage involves a strategically placed network ofprocessors known as health nodes utilizing lightweightand low power microelectronics with advanced high densitysolid state memory. These devices may communicate witheach other using a fiber optic data bus protocol such asFiber Data Distributed Interface (FDDI).Extensive real-time distributed data processing involvessoftware modules resident on the health nodes processing inparallel. This includes health diagnostic algorithms forfault isolation, health prognostic algorithms for detectingtrends and fault prediction, adaptive mission planning andscheduling which takes into account vehicle systems healthstatus and mission objectives and autonomous control of avehicle. Within these modules are sensor data validationfor improved reliability, model based reasoning which relyon models of system structure and definitions of nominalbehavior in comparison with actual system behavior andneural networks for data pattem recognition and learning.Ground IVHMThe two elements of ground IVHM are evolved controlroom architectures with advanced applications andautomated ground processing systems. Todays controlroom architectures have unique system-dedicated consoleswith hardwired panel switches. Evolved control roomshave a core of identical and reconfigurable consoles forflexibility and ease of maintenance. The advanced softwareapplications resident on these consoles include intelligentmaintenance scheduling and logistics coordination,diagnostic and prognostic algorithms for analysis of flightand ground systems, paperless work documents andreference materials and expert systems as tools for flightand ground control personnel for rapid identification ofproblems and corrective actions. Utilization of automated

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ground support equipment enables extensive paralleloperations including vehicle towing, jacking andpositioning; umbilical mate and demate; thermalprotection system, window, radiator panel and structuralinspections; rapid vehicle systems checkout; payloadremoval, installation and checkout; rapid servicing ofpropellants and other commodities; expedited rangeclearance and launch sequencing.

3 . HARDWARETECHNOLOGIESThere are several key characteristics of Space Shuttle eradata acquisition hardware technologies. Avionics boxes arebest described as large, heavy, high powered and requireactive cooling. Interfaces with these boxes are notstandard. Connectors of various sizes and shapes aredistributed throughout a vehicle providing power andcommunication between different types of sensors, signalconditioning devices, multiplexing devices and recorders.All sensors are point sensors meaning one sensor for onemeasurement with all the associated wiring. Avionicsarchitectures are custom or heavy and large ruggedizedcommercial versions such as Versa Module Eurocard(VME) bus. Also, there are extensive heavy runs of copperwiring for communication and power distribution. Datarates are relatively low as compared to commercialapplications. Similarly, data storage is relatively low andoften uses tape media.The above technologies are evolving into a more modem,distributed IVHM instrumentation system. Included arelightweight and low power avionics boxes, which requiregreatly reduced or no active cooling. Interfaces arebecoming more standardized which allows for a reducedparts count and more interchangeability. There are modularand distributed data acquisition architectures usingstrategically placed Health Nodes with localized dataprocessing. Multiple sensors and multiple parametricsensors are packaged together simplifying installations andproviding built-in redundancies through self-healing andself-calibration. Modem sensor types include ultrasonicflow, photonic strain/temperature/hydrogen oxygendetection, smart sensors with analog-to-digital conversionat the source, magnetic sensors for non-intrusive currentdetection, Silicon Carbide sensors for high temperatureapplications using thin film and sputtered parent metaltechniques, acoustic emission and microelectronic versionsof common sensors. Fiber optic communication such asFiber Data Distributed Interface (FDDI) or MIL-STD 1773as well as wireless communication reduces copper wiringrequirements. With this comes greatly increased bandwidthcommunication. Additionally, smart telemetry systemsfurther increase effective bandwidth by only transmittingparameter changes. High-density solid state recording in

the Gigabit range allows for increased numbers of sensorsand more extensive post-flight data analysis as acontingency operation.Further evolutions of these technologies will continue toreduce size, weight, power and active cooling requirements.This includes wireless power, wireless sensor networks,microhano electronicskomputers, optical power andelectronics, further advanced semi conductor materials,avionics embedded into structures eliminating boxes andcabling and overall continued miniaturization of sensors.(Ref 2 )

4. S o m m ECHNOLOGIESHealth Monitoring vs Health ManagementOne of the three elements of flight IVHM mentioned aboveis extensive onboard data processing. This includes theassessment of vehicle state, tracking of time-relatedconditions such as component degradation and drift, andrecovery and/or safing reactions to failures.In space environments near Earth, it has been possible tomanage spacecraft in the past without having onboardIVHM by adding to design margins and through extensiveground-based monitoring and control of a given spacecraft.Apart from large operations costs, this largely manualapproach becomes increasingly infeasible for deep-spacemissions where lightspeed transmission time lags becomesignificant compared to the time for failures to manifestthemselves.Given the relatively low performance of past space-qualified computers and the lack of formal verificationmethods for complex IVHM codes, initial onboardexperimental IVHM systems, such as those described inthis paper for X-33 and Space Shuttle, focused on healthmonitoring- hat is, acquiring and filtering data, sometimesperforming sensor limit checks, then transmitting the datato the ground as telemetry or storing it onboard for laterdownloading. In contrast, onboard health managementsystems also analyze, diagnose problems, and generatereactive plans onboard in real-time.

Integrated software architectures-Given multipleheterogeneous sensors, data types, and update rates, theseonboard health management systems need to be able tocombine and compare various health data sources, in real-time, in order to correctly assess current vehicle state.Sensor drift and component degradation often exhibitsymptoms, which can only be detected over time. These

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time dependencies add further complexity to onboardIVHM software. Further, physical process propagation lagsduring vehicle mode changes may cause apparent transientinconsistencies between the (expected) model vehicle stateand the (actual) transitioning state. This can in turn lead tofalse-positive diagnoses of failures without somerepresentation of and reasoning about time-varyingprocesses and events.Traditional command-driven software waits patiently forcommand strings onboard IVHM software is automatedand must be able to react to changing data values signifyingvehicle events.Onboard IVHM Software FunctionsSensor validation, data filtering andfision-In a data-drivenIVHM system, once sensor data is acquired it will beexamined by both a sensor validation program (to look forsensor failures) and a feature detection program (to flaghigh, low and drifting values).Event derection-Not all detected abnormal features reflectfailures some may reflect transients due to physical timelags during nominal state changes. One weakness ofconventional fault table or rule-based feature detection istheir brittleness or inability to automatically compensatefor transients. Consistency-based model-based reasoningapproaches such as those of DeKleer (Ref 3 or theLivingstone inference engine Ref 4 can propagate physicalparameters (such as fluid flow or temperature changes)which allows transient states to be followed as nominalrather than off-nominal events.Failure mode identification and recovery-If failures arediagnosed, a health status message may be sent bydownlink to a ground-based system. Optionally, if cost,schedule and software confidence permit, recovery orreconfiguration commands may be generated based on thenature of the failure.Task planning and scheduling-Ordinary state-changes aswell as failure recoveries require some kind of plan orcommand sequence. These plans may be pre-stored forsimple or commonplace actions, or generated dynamicallyduring flight by planning and scheduling software.

Execution of commands and tasks-Once a task plan hasbeen created or activated, some kind of executive processmust carry out the plan. Executives can be simple, loopingor single-threaded types or more complex multi-threadedtypes capable of executing multiple simultaneous plans.Integration with ground operations soffivare-Onboarddiagnosed failures and generated plans in turn may beintegrated with ground-based depot-level maintenanceprograms, as well as with mission operations. Thisintegration facilitates subsequent ground processing andvehicle turnaround times by virtue of optimizing the pre-positioning of spares, personnel, materiel and ground testequipment, prior to vehicle return. Figure 1 shows anotional IVHM onboard architecture which is integratedwith a ground-based planning and scheduling system.Examples of IVHM Software ArchitecturesOver the past decade, NASA has developed and testedseveral generations of experimental IVHM software whichhave implemented many or all of the IVHM softwarefunctions above.For example, in 1990 the Thermal Expert System(TEXSYS) demonstrated a model-based (De Kleerapproach) diagnosis capability together with data fusion,sensor validation and a separate executive for failureidentification and recovery of the Space Station thermalsubsystem. Ref 6 TEXSYS was successfully tested indirect, real-time control of a full-scale Space Stationprototype. Its chief drawback was its implementation inLisp (and hence need to occasionally perform softwaregarbage collection).Another example of IVHM software functions integratedwith ground operations is the GPSS (Ref 7) maintenanceplanning and scheduling system, which advanced to activeoperational use at NASAs Kennedy Space Center in themid-1990s and has subsequently saved tens of millions ofdollars in Shuttle refurbishment costs.This year, a new agent-based IVHM architecture was flownand successfully flight-tested on the Deep Space-1 DS-1)probe. As shown in Figure 2, the Remote Agentexperiment (RAX) incorporates the Livingstone model-based diagnostic engine (Ref 4 , a separate task onboardplanning and scheduling system, data validation, and amultithreaded executive.

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Static MaintenanceInto ation

DvnamicD ? . M l l l i C d YGeneratedDetailed

Finure 1.A proposed onboard IVHM software architecture for reusable launch vehicles (R ef D

Fiaure 2. Remote Aaent Exper iment ( R A X ) architecture.

May 1999 RAX experiment-A recent paper by Nayak et al.(Ref. 8 describes the 1999 RAX testing and validation indetail. Due to delays with unrelated spacecraft anomalies,the 3-week planned RAX test period was curtailed to twoweeks. Asteroid encounter preparation subsequently costRAX another week, leaving only one week for tests.Beginning on May 17 1999,RAX ran a 2-day series of testswhile resident on the DS-1 spacecraft. These tests werecurtailed at about the 70 completion level when a recoverycommand failed to be executed as expected from a simulatedspacecraft switch failure. Quick ground-based analysis ofthe softwares performance led to the discovery of a raretask execution deadlock bug which had eluded all previousground-based software verification and validation.This bug was deemed to be sufficiently rare in practice thatDS-1 mission managers preferred to leave it alone ratherthan risk inducing new, unknown bugs from an uploadedsoftware patch. RAX tests then were allowed to resume onMay 21 and ran to completion, accomplishingall experimentvalidation objectives.

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6. SUMMARY OFFLIGHT EXPERIMENTS De ep Space-IThe Deep Space-1 (DS-1) spacecraft, had a successful flybyof asteroid Braile in July 1999 and is well on its way to aflyby in January 2001 of the dormant comet Wilson-Harrington to be followed by a flyby of an active comet,Borrelly. DS-1 is validating 12 new technologies forscientific space missions of the next century including axenon ion engine and first use of autonomous navigation-mission operations using AutoNav remote agent IVHM

PHI ..IPCLT n

It is planned to fly an LH2 tank IVHM experiment on the X-33 precursor vehicle to the Lockheed Martin Skunkworks-led Venturestar RLV. This experiment will attempt to verifythe structural and functional integrity of the LH2 tank andprovide information to support rapid post-flight groundmaintenance. Sensor locations were selected based on

Figure 3.Proposed Space Shuttle IVHM ArchitectureN H M H TD sThe purpose of the Integrated Vehicle Health ManagementHuman Exploration and Development of Space (HEDS)Technology Demonstration-2 (IVHM HTD-2) was toadvance the development of selected IVHM technologies ina flight environment and demonstrate the potential forreusable vehicle ground processing savings. The focus ofthe experiment was real-time system health determination ofselected Orbiter Main Propulsion System (MPS), SpaceShuttle Main Engine (SSME) and Power Reactants Storage

critical areas as determined by analysis. These areasinclude:Sensor types include: strain (standard, thin film, fiberoptic), temperature (thermocouple, fiber optic, thermalimaging), hydrogen detection, smoke detection,vibroacoustic (microphone, accelerometer) and pressure.Additionally, ground based informed maintenancedevelopment is being performed by Lockheed MartinSkunkworks. (Re 12)

joints, attachment points, skins and stiffeners.

and Distribution (PRSD) functions. The technologies x 34developed included: advanced sensors such as fiber bragg-grating FI3G) photonic sensors for hydrogen, strain andtemperature sensing and smart sensors for hydrogen, oxygenand pressure sensing; distributed data acquisition using X-33Remote Health Nodes (RHNs) with Fiber Data DistributedInterface (FDDI) communication and a lightweightnowpower microelectronic hardware platform; real-timeinformation processing of SSME pump vibration and FBGsensors; solid state storage and ground based advancedcontrol room equipment and applications. The experimentsconsisted of an ar transport rack (ATR) for data acquisitionand processing, two X-33 RHNs, interconnect cabling,cabling for power R I G timing and cabling to 120 sensorsinstalled through the Orbiter aft compartment and payloadbay. Within this hardware platform resides the operatingsystem and information processing software. Theexperiment interfaced with a ground computer through theOrbiters T-0 umbilical for command and control. Follow-on IVHM HTDs are in the planning stages to develop andflight test the following technologies: SSME healthdetermination through spectroscopy, wireless sensors, neuralnetworks, nanolmicro electronics, integrated electronicchemical species sensors and miniature mass spectrometry.(Re 11)

The NASA IVHM Technology Experiment or X-vehicles(NITEX) has been selected to fly on the X-34 reusablelaunch vehicle being developed by Orbital SciencesCorporation. NITEX is led by Kennedy Space Center withadditional team membership from Glenn Research Centerand Ames Research Center. The goal of the X-34 IVHMflight experiment is to advance the technology readinesslevels of selected IVHM technologies within a flightenvironment and to begin the transition for thesetechnologies from experiment status into accepted RLVbaseline designs. Multiple flights of the experiment areplanned beginning in April 2001.The experiment will monitor the X-34 vehicle throughout allmission phases using detailed diagnostic algorithms to detectdegraded component performance as well as a system-levelhealth monitoring system that integrates information frommultiple components to perform real-time fault detection,isolation and recovery. In addition, the experiment willdemonstrate the use of an advanced, user friendly groundstation that combines information provided by the on-boardIVHM software with information obtained while the vehiclewas on the ground to provide high-level status informationon the health of the vehicle along with the ability to accessmore detailed information when required. The ground

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station will also provide justification for the inferences madeby the IVHM system and altemative recoveryrecommendations following a failure while in flight. It isplanned to fly NITEX multiple times. The focus of theexperiment will be on the X-34s Main PropulsionSubsystem (MPS) including the Fastrac Engine and theReaction Control System (RCS). into the current state of thevehicle by displaying high-level health status informationand providing access to the raw sensor data along with ajustification for the inferences that are made by thediagnostic algorithms. (Re 13x - 3 7An IVHM experiment focussing on the electromechanicalactuator and power systems will be embedded and firewalledinto the avionics system of the Boeing AdvancedTechnology Vehicle (ATV), or X-37. This experiment isled by Glenn Research Center with additional teammembership from Ames Research Center and KennedySpace Center. The X-37 is slated to begin five months ofApproach and Landing Tests (ALTs) beginning in early2002. In late 2002 the ATV will then be a space deployedvehicle from the Space Shuttle or expendable launch vehicle(ELV), maintaining itself on-orbit until it re-enters, returnsand lands automatically. Later versions of the initial X-37may be upgraded with additional on-orbit electrical power-generating capability, allowing it to loiter on-orbit for weeksor months. IVHM during these longer-duration, self-contained flight periods is similar in many respects to IVHMissues for long-duration deep space operations. Given anon-orbit loitering capability, constellations of X-37-derivedvehicles are conceivable. These would be a large operationsburden given traditional ground-based mission operations,but would be much more affordable if the vehicles werelargely self-contained with onboard IVHM capability.Also, intelligent X-37 ground IVHM will be developed byBoeing and Kennedy Space Center which will leverageBoeing Phantomworks Informed Maintenance efforts. Thissystem will focus on the health summary informationprovided by the flight experiment as well as additionalinformation already available in the vehicles telemetrystream. It will be included into an overall rapid vehicleturnaround demonstration planned utilizing a wireless workdocumentation system and a wireless communication systemfor maintenance personnel.

7. CONCLUSIONSIVHM technologies offer the potential for significantimprovement to safety reliability, maintenance andoperations for reusable launch vehicles and spacecraft.However, IVHM technology development is not mature andwill require effort, time and money to realize its fullpotential. A national IVHM has formed to develop thesetechnologies through an IVHM blueprint for the future.

8. REFERENCES[l] Gormley, T., r3rd Generation Blueprint for IVHM,presented at 31d Generatiodspaceliner 100 Conference atKennedy Space Center, May 1999.[2] Baroth, Edmund, Advanced Sensor System Workshop,JPL Publication 99-9, June 1999.[3] de Kleer, J. and B. C. Williams, Diagnosis withbehavioral modes, Eleventh International Joint Conjierenceon Artificial Intelligence, Detroit, MI, 1989, pp. 1324-1330.[4] Williams, B. C. and P.P. Nayak, A model-basedapproach to reactive, self-configuring systems,Proceedings of the Thirteenth National Coilference onArtificial Intelligence AAAI-96).[5] Merope Experiment Project Plan, draft, ComputationalSciences Division, NASA-Ames Research Center, MoffettField, CA, January 1999.[6] Glass, B.J., Erickson, W.K., and K.J. Swanson,TEXSYS: a large-scale demonstration of model-based real-time control of a space station subsystem, 7th IEEEConference on Artijkial Intelligence Applications, Miami,Florida, February, 1991.[7] Deale, M., et. al., The space shuttle ground processingsystem. In Intelligent Scheduling, Zweben, M. and Fox, M.(eds). Morgan Kaufmann, 1994.[8] Nayak, P.P., et. al., Validating the DS-1 Remote AgentExperiment, to be presented at the Fifth InternationalSymposium on Artificial Intelligence, Robotics andAutomation in Space (iSAIRAS-99), October, 1999.[9] Fox, J. Impact of IVHM Technologies on RLV GroundProcessing, presented at RLV Payload Processing andLaunch Operations Workshop, Cocoa Beach, Florida, June1998.[101 Fox, J., Integrated Vehicle Health Management(IVHM) Concepts for Space Shuttle, presented at SpaceShuttle Development Conference, July 1999.[ l l ] NASA Fact Sheet, IVHM HTDs, Kennedy SpaceCenter, Florida, May 1999.[12] Franklin, W., et. al., RLV LH2 Tank VHM MeetingMinutes, November, 1998.[I31 Clancy, D., Zakrajsek, J., Kruhm, D., NASA IVHMTechnology Experiment for X-vehicles (NITEX) ProjectPlan, May, 1999.

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9. BIOGRAPHIESJack FoxIntegratedManagementdevelopmentDevelopmentUpgrades at

is manager ofVehicle Healthtechnologyfor Advancedand Shuttlethe Kennedy SpaceCenter. He is responsible fo r the development of IVHMtechnologies f o r possible application on the Space Shuttle,future launch vehicles and spacecraft, He was projectmanager for tw Orbiter Integrated Vehicle HealthManagement Human Exploration and Development ofSpace HE DS ) Technology Demonstration IVHM HTD )flight experiments. Launches of the IVHM H TDs were onthe Orbiter Discovery on STS-95 in October I998 and STS-96 in May 199 9. Afrer receiving a B. S. rom Ohio StateUniversity in Aerona utical and Astronau tical E ngineeringin 1983, Jack began his career with NASA at KennedySpace Center. Jack ha s held a variety of technical position sin systems engineering, project engineering and advanceddevelopment fo r Space Shuttle and Payloads. He receivedan Astronaut Office Silver Snoopy award in 198 7 f o rcontributions to returning the Shuttle Program to fligh tstatus in the post-Challenger era. Jack comp leted a M. S.degree in Engineering Management fro m Un iversiv ofCentral Florida in 1995. Jack was awarded a NASAExceptional Service Medal in 1 999 fo r Space Sh uttle IVHMdevelopment.B .J. hss is a senior scientist inthe Computational SciencesDivision of the Iizformatioiz SystemsDirectorate at the NASA AmesResearch Center. He has beeninvolved with, and led, manyinformation technology-based research programs, includingin the areas of adaptive controls, wireless-basedcommunication systems, robotics, vehicle and system healthmonitoring programs, and the Surface Movement AdvisorSMA)Program. SMA is a major sofrware development thatserves to advise ground controllers as to how best to useairport taxiways and gate positions, and is now operationalat the Atlanta Hartsjield Airport. After receiving a B. S.from M.I.T. Aeronautics and Astronautics) in 1982 , his1987 Ph. D. fr o m G eorgia Tech pertained to the intelligent,adaptive control of time-varying systems such as robotmanip ulators or large space structures. Joining the staff of

NASA-Ames Research Center in 1987, he applied thissuccessfully to the control of large two-phase thermalsystems fo r the Space Station program. Brian retumed toschool and obtained an additional M. S. degree inGeophysics in 1992 from Stanford University, focu sed onmorphological models of scarp-like landfonns. Brian iscurrently responsible for information and automationtechnologies in the Human Exploration Office and worksclosely with the Center fo r Mars Exploration. He has also86

been involved in research on advanced vehicle and systemhealth monitoring software, as applied to space andaeronautical systems.