ARUSHA EXERCISE BRIEFINGNahom Beyene, PhD

Including slides from Cherice Moore (NASA) and Craig Maynard (NASA)

Exercise Design & Lessons Learned 1

Speaker Intro• Past Experiences @ Johnson Space Center

• Co-op Student• Grad Co-op• Aerospace Engineer

• Present Vocation: Assoc. Engineer @ RAND Corporation• Part-Time Passion: Technology Commercialization – a

testing methodology to validate the capabilities and forecast the risks of automated vehicles

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Exercise Equipment Design, Planning & ISS Lessons LearnedDeep Space Habitat SE&I Human Performance and Reliability TIM

March 27, 2012

Presenters:Cherice Moore (281-483-8780/ Adv. CMS Technology Development Manager)Craig Maynard (281-483-9316/ CMS System Manager)Patty Meyer (281-483-4496/ SA CMS Integration Lead)

ISS Capabilities

Any mission that exceeds approx. 30 days is expected to require the full set of capabilities that are reflected on ISS*.

*(<30 days requires a subset of the capabilities)

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Physiological Needs and ISS Answers

Countermeasure Purpose/Equipment

Aerobic Conditioning

Musculature Conditioning

Bone Loss

Sensorimotor

Psychological

DCS

T2

TVIS*

CEVIS

VELO*

ARED (USOS & RSA)

Exercise Tubing (Bungees)

For rehab only

Table Notes: Green = primary role of equipment; Yellow = partially supports; * = used for Russian crew

• Research is ongoing for requirements on future exercise equipment design.

• ISS equipment is meant to support 3 crewmembers within a single shift day.

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Equipment Capabilities and Resource Needs

T2 TVIS CEVIS AREDCapabilities Summary

0-12 mph treadmill, bungee restraint system

0-10 mph treadmill, active loading system

0-300W resistive ergometer

0-600 lb resistive exercise device

Total Operational Volume* in cu. Ft. (cu. m)

268 (7.6) ~106 (3) 154 (4.3) 228 (6.4)

Operational Mass (lbs) 2354 ~800 227 1200

Peak Power at max capability

2400 W 900W 60W 60W(includes laptop pwr)

Annual Mx Time (hrs) 18 31 4 38

Annual Usage Time (hrs for 3 crew)

~375 ~375 ~181 (not tracked by hours)

Requires additional Stowage volume?

Y Y Y Y

Has Software? Y Y Y Y

Has VIS? Y Y Y Y

* Volume includes installed/deployed hardware + human dynamic envelope

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Overview of Lessons Learned• Fail Operable • Scheduling Exercise• Importance of Life Cycle Testing • Corrective Maintenance• Planning for Software

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Plan for Arusha Exercise• Analyze Conditions Of Greatest RiskA lack of exercise capability for an extended timeframe is reason to bring the crew home and cancel the mission

• Prioritize Features and Subsystems by Protective Benefit

• Recommend Top Solution(s) with Full List of Alternatives/Contingency Measures

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Greatest Risk: Mission Abort

3 Criteria are proposed with quantities yet to be determined

• Consecutive Days without Exercise Countermeasures• 2 weeks, other?

• Cumulative Days (%) without Exercise Countermeasures• 33% of mission days by the end of week 6 and cont’d to mission

completion?

• Minimum combination of Exercise Countermeasures• Cardiovascular/strength training ratio (CSR) over the same time

frame?

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Workday Availability Analysis• Condition 1: Nominal Availability

A. Stationary Rover vs. Moving Rover Blackout DaysImplication of exercise while rover is in motion could be development of a VIS: Vibration Isolation System

B. Hyper Stacking Exercise CountermeasuresNeed to discover full-size interchangability or modular swap out design alternatives

C. Exercise Prescription Review

D. Planned Maintenance Scheduling (Hardware & Software)

• Condition 2: Reduced AvailabilityE. Priority Ops List – Activities that take precedence over exercise

F. Adjacent Nods Conflict Analysis – Activities in neighboring nodes that violate the exercise activity space envelope

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Team Invitation• Skill sets desired

• Architecture• Structures• VIS: Vibration Isolation (maybe)• Logistics/Mission Ops• Space/Life Sciences or Exercise Physiology• Sustaining Engineering• Software• Power• Hardware (me + anyone interested)

• Team size desired – 7• Minimum team size – 3

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Exercise Equipment Design

All flight exercise equipment tends to be composed of the following subsystems:

Technology concepts to improve each of these areas are being proposed.

Human-to-Machine Interface (e.g. handles, harnesses, control panel, etc.)

Machine

Software (e.g. firmware, laptop software, etc.)

Vibration Isolation System/Mounting Hardware

Crew Monitoring Equipment (e.g. for heart rate, ECG, etc.)

Support Equipment (e.g. mx, calibration equip, spares)

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Systems IntegrationCoordination during mission concept phase prior to vehicle development needs to include Exercise Countermeasures inputs for strategy and initial vehicle design requirements planning.

Environmental Control & Life Support System – for regulation of localized ppO2, ppCO2, humidity, air flow, heat, odors

Structures & Mechanics System – for interface reinforcement, vehicle vibration and harmonic concerns

Acoustics System – for planning noise and equipment placement Vehicle Stowage – for planning stowage volume for regular use items, maintenance items and

spares Power System – for planned hardware power usage Avionics/Software – for planned data communications Transfer Vehicle Logistics – for upmass (and downmass), volume, hatch constraints

coordination Flight Crew Equipment System – for coordinating responsibility for exercise clothing and tools

delineations

(Countermeasures System (CMS) is responsible for integrating Vehicle Systems, International Partners, Countermeasures Hardware Providers, Safety and Mission Assurance, Operations, Medical and Research for the corresponding program)

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Some Lessons Learned

Risk A lack of exercise

capability for an extended timeframe is reason to bring the crew home and cancel the mission

Lessons Learned Fail Operable Scheduling Exercise Importance of Life Cycle

Testing Corrective Maintenance Planning for Software

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Fail Operable

Observed ALL exercise equipment has had failures in some manner during its

use on ISS. Hardware designs have allowed for redundant capability for

continued crew exercise ARED Instrumentation Box failure and CEVIS Control Panel

failure are designed to operate without power Both TVIS and T2 allow for passive modes in the case of a motor

failure Most of ARED cable exercises may also be performed with bar

Lesson Learned Design to fail operable where possible Provide alternate equipment to meet physiological needs in case of

total failure

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Scheduling Exercise Observed

Scheduling exercise tends to be the primary driver on how the rest of the day’s timeline is constructed.

Of 6.5 hours available time, aerobic exercise equipment usage requires about 1 hour/crew/day and resistive exercise requires about 1.5 hrs/crew/day.

Individuals have preferred times of day and order for exercises Exercise may be constrained by co-located operations and vehicle

structural constraints (e.g. re-boosts, docking, etc.)

Lessons Learned More equipment provides more operational flexibility Either design the location for the equipment to avoid co-located

operations or vehicle constraints, or have multiple locations for exercise equipment.

Research may require additional scheduling constraints Hardware should be designed so as not to be the limiting factor on

scheduling (e.g. thermal or powered-on constraints)

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Importance of Life Cycle Testing Observed

Very limited life cycle testing was originally performed on TVIS, and subsequently TVIS required numerous, unexpected on-orbit corrective maintenance activities.

Life cycle testing is MUCH more expensive on-orbit than on the ground

Designers can be overconfident in believing their equipment will perform reliably

Life cycle testing is only as good as its ability to replicate actual on-orbit usage and environment

Life cycle testing performed on ARED, T2 and TVIS SLDs identified most of the limited life issues during development phase and subsequently had far fewer unexpected on-orbit corrective maintenance activities.

Lesson Learned Life cycle testing is mandatory if you want reliability and insight into performance and

maintenance needs. Test as you fly; Fly as you test Life cycle testing should be performed on flight-identical hardware; Workmanship

variability can invalidate your life-cycle test results Mechanical simulation of exercise can be an inadequate representation of actual

human usage Human usage is unpredictable and can induce unexpected failure modes

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Corrective Maintenance

Observations Unexpected failure modes can (and will) occur (e.g. bearings,

wire ropes, control boards, etc.) If no (or limited) ORU spares available, sub-ORU sparing and

repair may be preferred. Without design for sub-ORU repair capability, repair becomes

more complex if possible.

Lesson Learned Design for sub-ORU level repair (e.g. swappable bearings,

connectors instead of soldering) Design with commonality in mind for parts and available

tooling Provide sub-ORU spares

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Planning for Software

Observed ALL exercise equipment (except unpowered iRED) has had Control Panels

and data transfer requirements

ALL software (except for TVIS) has required subsequent updates after delivery

Frequent cause due to inadequate development schedule prior to delivery

ALL equipment has experienced regular data transfer issues (both human and technical)

Lesson Learned Adequately plan for software development and testing

Consciously design for wired vs. wireless vs. sneaker-net (not recommended)

A single control panel/laptop platform with equipment-specific software will allow for cross-equipment redundancy (and minimize sparing)

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Backup - Acronyms

ARED – Advanced Resistive Exercise Device

CEVIS – Cycle Ergometer with Vibration Isolation Stabilization

CMS – Countermeasures System

ECG – Electrocardiogram

iRED – interim Resistive Exercise Device

Mx – Maintenance

ORU – Orbital Replacement Unit

RSA – Russian Space Agency

VELO – Russian Ergometer

T2 – Second Treadmill

TVIS – Treadmill with Vibration Isolation Stabilization

USOS – US On-Orbit Segment

VIS – Vibration Isolation Stabilization

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