# Presentation: 317476

## Section 2

_***Section 2***_
***Mission Overview***

*** ******. . . Dale Schulz***
*EO-1 Project Manager*

## What is EO-1?

***What is EO-1?***

***Designed to flight validate breakthrough technologies applicable to Landsat follow-on missions***
***Specifically responsive to the Land Remote Sensing Policy Act of 1992 (Public Law 102-55) wherein NASA is charged to ensure Landsat data continuity through the use of advanced technology:***
***Multispectral Imaging Capability to address traditional Landsat user community***
***Hyperspectral Imaging Capability to address Landsat research-oriented community -- backward compatibility essential***
***Calibration test bed to improve absolute radiometric accuracy***
***Atmospheric correction to compensate for intervening atmosphere***

## EO-1 Technologies

## Primary Requirements

***Primary Requirements***

***Successfully flight validate the assigned technologies***
***Launch ASAP after WARP return (Aug. 2000)***
***Develop, launch, and operate the EO-1 Mission for one year within the ESE budget cap***

***Minimum Mission***

***Successfully flight validate the multispectral imaging technologies incorporated in the Advanced Land Imager***
***Defined in EO-1 Mission Success Criteria***
***Meet the above launch schedule and budget cap***

## EO-1 Spacecraft

## GN&C:
Three-axis stabilized
Pointing accuracy of 0.022° (3) in all three axes
Jitter is <5 arcseconds (3)
Star camera
GPS
Independent safehold processor
Partial MAP design
Power:
Deployable three panel solar array; 633W EOL
300W orbital average requirement
NiCd battery 50Ahr
Bus = 28 ± 7 VDC
MAP design
C&DH:
Mongoose V processor @ 12 MHz
1773 fiber optic data bus
MAP design

***Spacecraft Subsystems***

***GN&C:***
***Three-axis stabilized***
***Pointing accuracy of 0.022° (3************) in all three axes***
***Jitter is <5 arcseconds (3************)***
***Star camera***
***GPS***
***Independent safehold processor***
***Partial MAP design***
***Power:***
***Deployable three panel solar array; 633W EOL***
***300W orbital average requirement***
***NiCd battery 50Ahr***
***Bus = 28 ± 7 VDC***
***MAP design***
***C&DH:***
***Mongoose V processor @ 12 MHz***
***1773 fiber optic data bus***
***MAP design***

## Spacecraft Subsystems (Continued)

***Spacecraft Subsystems ****(Continued)*

***Propulsion:***
***Hydrazine***
***Used for orbit maintenance, formation flying, and correcting insertion errors***
***Four thrusters @ 0.2 lb each***
***Structure:***
***Aluminum***
***Mass = 370 Kg***
***Hexagonal Right Prism***
***Equipment panels serve as radiators***
***Payload Interface:***
***Alignment measured to 20 arcseconds***
***Thermally coupled to spacecraft***

## Ground System Requirements Summary

***Ground System Requirements Summary***
*Ground stations to receive, process, and route science and HK data to GSFC*

***X-Band:  Receive 80 Gbits of science data each day at 105 Mbps ***
***Record the received X-band data on hard media, mail to GSFC, and store raw data for 30 days***
***S-Band:  Receive data at selected rates up to 4 Mbps***
***Housekeeping data: Route selected virtual channels to GSFC in real time, record up to 200 Mbits of data each day, and FTP recorded data to GSFC within one hour. Store raw data for 30 days.***
***Backup science data (up to 10 Gbits per day): Process as with X-band.***
***Perform Level 0 processing on the science and HK telemetry***
***Fill holes, reorder science into band order***

## Ground System Requirements Summary

***Ground System Requirements Summary***
*(continued)*
*GSFC to receive and process data sent from the ground station*

***Process MS/PAN science data to provide at least 200 paired scene comparisons with Landsat-7***
***120 scenes for ALI 30 day checkout***
***100 scenes for ACS to ALI in orbit calibration***
***800 scenes total first year***
***HYPERION Science Processing at TRW***
***Maintain an orbit of sufficient precision for scene comparisons***
***Follow Landsat-7 Ground Track ± 3 km and ************1 minute behind***
***Maintain the health and safety of the spacecraft***
***Validate and calibrate onboard orbit and attitude subsystems***
***Perform orbit maneuver control to enable formation flying***
***Provide mission planning and command management***
***Archive raw and processed data***

## EO-1 Contracts / Agreements

***EO-1 Contracts / Agreements***

## Slide 11

## Schedule

***Schedule***

## Interpoint Converter Problem

***Interpoint Converter Problem***

***Two Interpoint MTR series dual output DC/DC converters intended for use in space failed during environmental testing***
***Oct. 99, SN 0563 used in the MAP Autonomous Star Tracker***
*Loss of negative output voltage during first vacuum cycle at ambient temp*
*Recovered functionality when repressurized*
***Jan. 00, SN 0048 used in an electronic subsystem onboard an LMMS classified spacecraft***
*Loss of negative output voltage during 3rd vacuum cycle and 5th temp cycle (120 hours total vacuum operation time)*
*Also recovered functionality when repressurized*
***Both failures were the result of a broken solder joint at location L2 due to creep-to-rupture (see photo)***
***Failure mechanism is unique to Interpoint MTR dual output converters, not present in Interpoint’s single or triple output models***

## Interpoint Converter Failure Mechanism

***RTV adhesive is placed on top of transformer to secure lid of the converter housing to transformer***
***Wire soldered to pad L2 is staked with RTV to the side of the transformer***
***Converter is pressurized to one atmosphere with GN******2 ***
***Under vacuum the converter’s lid “oil cans” ************ 10 mils***
***Since the transformer is adhered to the lid, it lifts up when the lid deflects***
***Wire solder joint to L2 is stressed when transformer lifts upward***

## Interpoint Converter Failure Mechanism (2)

## Interpoint Converter Impact to EO-1

***Interpoint Converter Impact to EO-1***

***EO-1 has a total of 5 of the MTR28XXD devices***
***ACE I/O card***
***C&DH LVPC card***
***GPS Converter***
***Star Tracker (2)***
***GPS is associated with a Category III technology and therefore does not impact the Minimum Mission; fly “as is”***
***X-rays of both converters in the Star Tracker are on file as a result of working an unrelated issue. Critical spacing of staked wire in both converters has been judged to be acceptable; fly “as is”***
***Both of the other 2 devices are in the ACDS box. Both are critical to the Minimum Mission success***

## Interpoint Converter Plan

***Interpoint Converter Plan***

***ACDS box to be de-integrated from the Spacecraft***
***Both cards to be removed and the parts X-rayed to determine the spacing of the staked wire***
***If both parts have wire spacing that meets an established criteria, then the boards will be re-installed in the box, it will undergo a box functional test and an unpowered workmanship vibration, and the box will be re-integrated.***
***If one or both of the parts does not meet the criteria, then they will be replaced with parts that do. Then the box will undergo more extensive environmental regression testing.***
***Three Axis Powered Vibration***
***Four Thermal Cycles***
***Box-Level Functional***

## Work Remaining Prior to Shipping

***Work Remaining Prior to Shipping***

***Re-integrate IRU***
***Re-integrate WARP***
***ACDS rework and additional testing due to Interpoint converters***
***Finalize all bays except Bay #3***
***Finalize flight software***
***Conduct T/V #2***
***Two Comprehensive Performance Tests (CPTs)***
***X-Band ground station compatability verification***
***Solar array integration***
***Functional test***
***Mass properties***
***Pack up***

## EO-1 I&T Schedule Flow - Success Schedule

## EO-1 I&T Schedule Flow - Replace D/C D/C Converters

## Thermal Vacuum II

***Thermal Vacuum II***

***Decision has been made to perform a second spacecraft-level T/V test as a final risk mitigation***
***Objective is to demonstrate that EO-1 is ready to launch!***
***Final hardware and software configuration***
***Provide T/V cycles for WARP and ACDS***
***Two thermal cycles at the beginning with a 72 hour hot soak at the end***
***While in Vacuum, plan to do the following:***
***Day 1 and 2, launch simulation with contingencies***
***Instrument turn-on simulation***
***Normal operation simulation***
***Final Comprehensive Performance Test***

## Mission Cost