space shuttle eva opportunities

8/7/2019 Space Shuttle EVA Opportunities

http://slidepdf.com/reader/full/space-shuttle-eva-opportunities 1/22



Pc

- - - . c_

4 ASTRONAUT EDWARDH. WHITEJune 3. 1965 A.D.Gemini - itan 4

A unique role that man plays in the United Statesspace program began when Astronaut Edward H. White IIleft the protective environment of his Gemini IVspacecraft cabin and ventured into deep space. His ex-cursion - o perform a special set of procedures in a newand hostile environment - arked the start of the uniquescience of Extravehicular Activity (EVA).

Gemini mis on s proved N A o be a viable techniquefor performing orbital missior! operations outside thespacecraft crew compartment. Then, as Gemini evolvedinto Apollo. and Apollo into Skylab. EVA mission objec-tives pushed the science and art of EVA to their limit.New, more sophisticated concepts and methods wereperfected. extending man's capability to obtain produc-tive scientific return from the space environment. And, ofcourse. Skylab demonstrated the application of EVA tech-niques to unscheduled maintenance and repair opera-tions - alvaging the program and inspiring its partici-pants to new heights of acconiplishment. Because of thispast success and usefu!ness, EVA capability has beenbaselined into the Space Shuttle program.

The National Aeronautics and Space Administration(NASA).in its Shuttle Orbiter program, is currently prepar-ing to delwer to orbit payloads that may vary considerablyin design and purpose. The payload may be a laooratoryhousing single biological cells or hausing several scien-tist astronauts. It may be an entire astronomy observatoryor a "small" component of a mammoth solar power sta-tion. N A can provide sensible. reliable and cost-effec-tive servicing operations for these payloam because EVA

gives the payload designer the options of orbital equip-ment maintenance, repair and replacement without theneed to return the payload to Earth or, in the worst case, toabandon it as useless space junk. Having EVAcapabilitycan help maximize tt e scientific return of each nitssion.

This brochure is meant to \)e a stimulus to the payloadcommunity by providing an insight into the opportunitiesof EVA sufficient to establish EVA as a primary designconsideration.

.17



EVA Aids

4 THE REMOTE MANIPULATOR

SYSTEMir available t o aaalat E VAcrawmembarr in he tranrport andporitlonlng of large payloadcomponent@ urlng he orbitalaammbly p r m s r and provider aready trmalation path betweenOrblter and payload.

To ensure maximum EVA capabilities. the following support equipmentwillbe available for each Shuttle mission:

Remote Man ipulator SystemThe Remote Manipulator System consists of a large external arm which. in con-

junction with certain payload supportin(l equipment. is capable of deploying.retrieving and operating on payloads weighing as much as 65.000 !bs. The systemis an electromechanical device. 15.2 meters (50 11) long. having shoulder, elbowand wrist joints along with an end effector The manipulator is cor ' ii !!ed from theaft crew station on the Flight Deck through direct vision complemented by a closedcircuit television system with cameras mounted on the manipulator arm and in theCargo Bay. The Shuttle Orbiter has baseiined one Remote Manipulator Systemmounted 99 the left side longeron of the Cargo Bay.

During non-EVA periods. the Remote Manipulator System can remove payloadsfrom the Cargo Bay and deploy them in a stabilized condition by the use of specialguideways and retention devices. Stabilized payloads can also be retrieved forreturn-to-Earth or on-orbit servicing. Unique payload servicing requirements.however. may require the addition of payload-provided, special purpose end effec-tors.

When used to assist the EVA crewmembers, the Remote Manipulator Systemmay perform one or more of the following useful functions.

It can effect multiple transfers of equipment betweer, the EVA work area and thereplacement equipment stowage area.Equipped with handrails. i t can be used by the EVA crewmember as a transia-tion path to remote areas on the payload or Orbiter that require servicingThe attached lights can be used to supply additional lighting at the work area.and the attached closed circuit TV camera can zld in payload inspection tasksand in task coordination with the other Orbiter crewmembers and with theground

Tools, Restraints, Ancillary Equipm entTo perform equipment maintenance. repair and replacement. the EV A

crewmember requires cec tain tools. tethers, restraints and portable workstationsA standard off-the-shelf tool set will be available for use in supporting EVA

payload operations These tools wil l be kept in the NASA ground inventory andflown as required for each payload Any payload-unique ools required will be fur-

nished by the payload user A primary design goal. however, will be to design thepayload components to be cost effective by allowing stande? I ASA-suppliedhand tools to be used for their servicicg

The portable workstation will be the crewmember's restr&,n .g piat'mn whileperforming EVA tasks and will provide foot restraints. stowage for ', ;s. tethers, aportable light and other ancillary equipment The workstation may attach directly tothe payload, to L' Irbiter structure or even to the Remote Manipulato: System insupporting variou EVA tasks Designers requiring EVA worksta!icr.s for theirpayloads will either build their own workstations per NASA specificdtions. or makeuse of any existing portable workstation(s) that is part of the N4S4 Orbl!er baselinesupport equipment inventory

5



MANNED MAl&UVERINQ UNITOPERATIONS n the n w r vlclnlty of theOrbiter allow a close-up nspectlon of

payload components which are beyondthe envelope of the Carg o Bay andreach of the Romote ManipulatorSystem.

Handrails. crew restraints and adequate lighting will be available to the EVAcrew to traverse safely to and from he workstation and payload. However, crewmobility and restraint provisions designed onto or into the payload as well asany special external or internal payload ighting fixtures must be payload pro-vided and self sufficient.

The payload designer is encouraged to purchase and use standard, NASA-specified "u ni ve d" or "multimission" EVA support hardware where mssiblein order to minii;iize R I A crew training. operational requirements and cost.

Manned Maneuvering UnitWith the Manned Maneuvering Unit. a propulsive backpack device, an EVA

crewmember can reach areas beyond the Cargo Bay he could not reach otherwise. The unit. a modular device stowed n the Cargo Bay and readily attachedto the Extravehicular Mobility Unit. can be donned. doffed and serviced by asingle crewmember as needed during an EVA period

Since the Manned Maneuvering Unit has a six-degree-of-freedom controlauthority. an automatic attitude-hold capability and electrical outlets for Suchancillary equipment as power tools. a portable light. cameras and instrumentmonitoring devices. the unit is quite versatile and adaptable to many payloadtask requirements.

Moreover, Since the unit need not be secured to the Obiter by tethers orother restraining devices. the crewmember can use it t: "fly" unencumbered oberthed or free-flying spacecraft work areas, transport cargo of moderate size

such as might be required for spacecraft servicing on orbit and retrieve small,free-flying payloads which may be sensitive to Orbiter thruster perturbation andcontamination (the unit's own low-thrust, dry, cold gas nitrogen propellantcauses minimal disturbance with no adverse contamination). In future applica-tions, such as in-space assembly of large structures. the EVA crewmembe: canw e the unit to easily position himself for supervising and inspecting automatedtechniques or manual assenloly When the Manned Maneuvering Unit IS flowrlto support payloads. its weight and volume will be allotted to payloads

EARLY MANNED MANEUVERINO UN n COllCEPTS



EVA CapabilitiesGiven adequate restraints. working volume avd compatible man.

machine interfaces. the EVA crewmembers can duplicate almost anytask designed for manned operation on the ground.

The following typical EVA tasks demonstrate the range of EVAoppor-tunities available to the payload designer.

0 Inspection. photography and possible manual override of vehicleand payload systems, mechanisms and components

0 Installation. removal or transfer of film cassettes, material samples,protective covers, instrumentation and launch or entry tie-downs

0 Operation of equipment. including tools, cameras and cleaningdevices

0 Cleaning of optical surfaces0 Connection, disconnection and storage of fluid and electrical umbili-

0 Repair. replacement, calibration and inspection of modular equip-

0 Oeployrl ler t retracticn and repositioning of antennas. booms and

0 Attachment and release of crew and equipr- i t restraints0 Performance 1 experiments0 Cargo transfer

cals

ment and instrumentation on the spacecraft or payloads

solar panels

These EVA applications can demechanize !he operational task andthereby reduce design romplexity (automation!. simplify testing andquality assurance programs, lower manufacturing costs and improve theprobability of task success

Shuttle E V A Timeline

6vn usersttens (6 hts mrimum)

Shuttle program provid-

Tw o &hour ( m a r ) . 1 or 2 m nE VA 6 pe r flight

I EV A crew trelmng

. Remote Yanipukwr System

E VA suppart

Support Wuiprnrnt (tools.roMr~(n(8, igW, TV . etc.)

. -

P r y b e d options

Additional E V A consumable6

Right specific WA crew trainin(

e Spedei Remots Marupubbr

System end effectors

Q ~ s 6 L e l w a r t equipment

3 Yenwd Meneuverlly Unit

Post EV Abporations

71 5 hrs)

0



develop payload operations techniques. efficient use of the N A upport equip-ment and crew procedures tasks equired to do the payload EVA lob Trainingdevices employed in this operational skill development may include the full-Size Orbiter "one-g" mcckup. the Orbiter unaerwater neutral buoyancy (zero-g)trainer. the altitude chamber, the Extravehicular Mobility UnitlAirlock trainerand the various Remote ManipUlatG* System and Manned Manewering Unitpart- and full-task simulators

Supplier and User Training Responsibilities

To achieve flight crew readiness for any given payload EVA missimrequires. from the conception of EVA requirements to the actual in-flightachievement of the payload objectives. a coordinated Shuttle pro-gramlpayload user effort. To this end, the Shuttle program accepts thefollowing responsibilities for crew training in N A payload operations:

0 To provide the training required to prepare a crewman to perform EV A in adeep space environment in support of planned, unscheduled or contingencypayload operations.To provide the Orbiter one-g. neutral buoyancy. Extravehicular Mobil ityUnitlAirlock. Remote Manipulator System and Manned Manewering Unittrainers

0 To provide a standard complement of basic Orbiter training hardware, i e.,handtools. tethers, workstations. foot res!ratnts. handrails. etc

0 To provide the detailed cre.v procedures required to support each training

exercise

In turn. the Shuttle program wil l require the payload user to accept thefollowing responsibilities.

0 To provide the initial set of payload system oper,:ing procedures to serve asthe basis for detailed crew procedures developmentTo provide payload-specific raining articles that have a direct EVA interface.Depending upon the EVA task requirements. one-g and neutral buoyancytraining articles could be required The fidelity will be suitable to the task.more critical crew interface tasks will require higher fidelity training articles

0 To provide specialpayload handling and support tools and equipment not inthe standard NASA inventory

0 To provide Special Remote Manipulator System end effectors required forpayload EVA suppor!

0 To provide payload requirements for a Manned Maneuvering Unit

Oollars and Sense

At this point the Shuttle "bser" should recognize several potentialmonetary advantages of a payload system designed and built aroundestablished EVA operational guidelines. First, an EVA system can allowsignificant design simplifications saving dollars otherwise needed torautomation Consequently, specialized crew training in complex hard-ware is reduced, minimizing or eliminating "flight specific" training re-quirements. Also, as a result of their "advanced" tratning, which is freeto the user, Orbiter crewmembers assigned to a specific payload mis-sion will be able to accomplish many standxdized EVA tasks. By usingas many of these standardized EVA tasks as possible in the design ofhis system, the user can save additional training dollars 15



Program FeaturesEven on the clearest d ay s and nights. the atmospnertc envelcpe encasing the Em stgniftcantly degrades

astan~mical XtsewvatiOn In attempts to gaze through 11. the astronomer tin& the sight disforled and biwred



Pursuit

4 ONE MAN'S LIFETIME- canvaschronokgy of man's aerosp aceinventiveness spannin9 the last sevendecades

Man has only begun to realize his achievement poten-tial in meeting the scientific and environmentalchallenges above his planet Extravehicular Activity hasbeen shown to be one effective means of capitalizing onthis potential Other methcds ,re available to meet ex-perirnen! task objectives Automated techniques and soloRemote Manipulator System utilization are viable means

of meeting specific payload orbital operations 'equire-ments But. as in the case of EVA. each method has :tslimitations. operational constraints and relative cost-effectiveness The payload designer must be thoroughlyfamiliarized with the various modes of task accomplish-ment in order to arrive at the best solution for applicatiorto the payload, one that is economical by design andreliable in operation.

Within the Johnson Space Center Crew Training andProcedures Division. the EVA Systems Section providesliaison with the payload community for experiment EVAoperations development Engineers in this section havemultiprogram EV A experience which enables them toconsult with interested payload principal investigatorsand designers and to assist them in determining the EVApotential for their payload and in optimizing its use.

In addition to providing EVA operations consultatim.the EVA Systems Section publishes the JSC Shuttle EVADescription an d Design Criteria document (ref 1 Thepurpose of this document is to prwide engineering per-sonnel and payload principal investigatms involved inEVA design. planning. operations and training with thedefinition of Orbiter EVA provisions. equipment andoperations along with hardware design requirements andcapabilities of the EVA crewmembers

For Orbiterlpayload interface information. the payloaddesigner is further directed to the Johnson Space CenterSpace Shuttle System Payload Accommodationsdocument (ref. 2) which describes the capabilities of theSpace Shuttle System to accommodate payloads anddefines the interfaces between the Space Shuttle Systemand the Shuttle payloads

19



References

4 8

44

4 0

36

3 2

E 28

24

BL

E4

20

16

12

8 -

4 -

1 Shuttle EV A Descr:cr!or!an d Design Cr,feria. S C 1061 5

-------

--

-

%P

0 -

2. Space Shutt le System Payload Accomm odationsJSC 07700, Volume XIV.

Figure 1 - E V A growth within previdus NASA manned space prograr7is

IP

I Program I EV A manhours 1

0N

u *. - e

Total 264.50

c

0

N

X x m 1 1 1 2 1 4 1 5 1 6 1 7 1 2

Gemini Apollo Skyl ab

U.S manned space mission4 utilizing E V A

space shuttle eva opportunities

Documents