THEMIS peer PDR Summaries 1 October, 2003 MPDR RFA#4 TITLE: Provide Design Information from the Instrument Peer Reviews REQUESTED BY: Joseph Bolek, Mark.

THEMIS peer PDR Summaries 1 October, 2003 MPDR RFA#4 TITLE: Provide Design Information from the Instrument Peer Reviews REQUESTED BY: Joseph Bolek, Mark Goans SPECIFIC REQUEST: Provide peer review presentation packages containing design information presented at the instrument peer reviews/PDRs. Also provide peer review summary reports for each instrument that identifies the content of the review and discussions of the flow-down of requirements, ability of the design to meet functional and performance requirements, and maturity of the design relative to the preliminary design phase. SUPPORTING RATIONALE: Design details on the instruments were not presented at the mission PDR. The review team did not attend the peer reviews and any instrument PDRs, therefore, we do not have sufficient insight into the details of the designs.

THEMIS peer PDR Summaries 2 October, 2003 RESPONSE : Bus peer review information was provided to Frank Snow at the bus PDR in hard copy and CDROM. Instrument peer review information has been publicly available at the THEMIS ftp site and the information was provided to the review team at the MPDR verbally and shortly thereafter by email: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/ For FGM, presentations, attendees and report: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/FGM ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/FGM/PDR_BS_Attendees.jpg ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/reviews/FGM_EPR_Report_Final.doc For SCM, presentations, attendees and report: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/SCM/ ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/SCM/SCM_liste particip_peerPDR.doc ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/reviews/SCM_EPR_Report_Final.doc For ESA/SST/EFI/IDPU/BOOMS presentations, attendees and report: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/ESA/ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/ESA/* …/SST, …/EFI, …/IDPU, …/MAGBOOMS/ ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/peerPDR_attendees_UCB20031015-17.xls ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/reviews/UCB_Instruments_EPR_Report_Final.doc For GBO presentations, attendees and report: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/GBO/* ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/peerPDR_attendees_UCB20031015-17.xls ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/reviews/GBPReviewPanelReport.doc For MsnOps presentations and report: ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/Mftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/MsnOps/ ftp://apollo.ssl.berkeley.edu/pub/THEMIS/1.1%20Management/MEETINGS/PhaseB_PDR/reviews/KVRichon_ThemsFD&MOPeerRvwPanelRpt.doc

THEMIS peer PDR Summaries 3 October, 2003 In the ensuing pages please find summaries of the bus and instrument PDR agendas first. It is followed by a flowdown of instrument requirements, adherence of the design to those requirements. Design maturity is beyond PDR level, as evidenced by the peer review reports and as surmised by the MPDR reviews attended by the IIRT. We ensourage the IIRT to visit the THEMIS ftp site and take a look at the detailed design information presented in the reviews. A CDROM with both the bus and instrument peer reviews will be sent to the chairs of the IIRT shortly.

THEMIS peer PDR Summaries 4 October, 2003 Bus peer PDR process and attendees#1 Steve Brodeur former Head of GSFC Mechanical Engineering branch and Jim Barrowman former head of the Explorers Office at GSFC chaired the reviews. Other Swales Engineers, not directly associated with the THEMIS program, were also present and served as informal reviewers, and contributed their verbal comments and questions during the presentations, as well as writing RFAs, Concerns, and Comments. The complete list of attendees is contained in each Subsystem summary memos. Notes/Minutes from the meeting were recorded by Kevin Brenneman and are included in each Subsystem’s memo. Also included are the RFAs, Concerns, and Comments/Suggestions for each subsystem. Note only RFAs were officially required to be tracked for resolution in this process (general practice) however a number of the Concerns and Comments/Suggestions were captured and incorporated into the PDR presentation materials. Per the guidelines provided by Swales Program Management (part of THEMIS EPRP) and consistent with a PDR level design the Subsystem leads were directed to present the subsystems requirements, configuration, performance, verification program, etc. in an open forum with the review team. Consistent with good Peer Review protocol open exchange was encouraged and facilitated by the Review Chairman. The System Overview on the second day did not have reviewers since it only presented an introduction to the subsystems for the benefit of the review team. A summary memo was prepared to document the minutes from each presentation. An internal working meeting/informal review was held on the afternoon of October 10 th on I&T and EGSE however this meeting was not subjected to the same Peer Review requirements. No actions were taken from that meeting, and no external reviewers were present, so it is not included in this Peer Review summary. The detailed memos which were generated in bus peer PDRs fed into the MPDR presentations but are not included in the CDROM. However they are available to the Program Manager and the PI for their review. They can be made available to the Explorer’s office upon request.

THEMIS peer PDR Summaries 5 October, 2003 Bus peer PDR process and attendees#2

THEMIS peer PDR Summaries 6 October, 2003 Instrument peer PDR reviewers #1

THEMIS peer PDR Summaries 7 October, 2003 Instrument peer PDR reviewers #2

THEMIS peer PDR Summaries 8 October, 2003 FGM Preliminary Design Review October 8-9, 2003 Braunschweig / Germany

THEMIS peer PDR Summaries 9 October, 2003 FGM-Agenda October 8, 2003

THEMIS peer PDR Summaries 10 October, 2003 FGM-Agenda October 9, 2003

THEMIS peer PDR Summaries 11 October, 2003 FGM Requirements (1) IN.FGM-2. The absolute stability of the FGM shall be less than 1nT -Determination of 3 offsets and 9 elements of the calibration matrix (scale values, non-orthogonality, sensor orientation) through in-flight calibration once per orbit -Spinning S/C provides 8 of 12 calibration numbers -Scale values are known accurately enough from pre-flight calibration -The determination of the spin axis offset can be done to 1nT accuracy by known physics during a standard orbit and to +/-0.1nT accuracy when being in solar wind IN.FGM-1. The FGM shall measure DC and low frequency perturbations of the magnetic field

THEMIS peer PDR Summaries 12 October, 2003 FGM Requirements (2) IN.FGM-3a. The relative stability of the FGM shall be less than 0.2nT/12hrs IN.FGM-3b. The relative stability of the FGM shall be less than 0.1nT/hr -Sensor noise:< 10pT/sqrt(Hz) @ 1 Hz IN.FGM-5. The FGM noise level @ 1Hz shall be less than 0.03nT/sqrt(Hz) -Offset / Time:< 0.1nT/h; < 0.2nT/12hrs; < 1nT/year; -Offset / Temperature:< 0.1nT/°C -Scale value / Temp.:< 24ppm (0.8nT/°C @ 32000nT) -Orthogonality / Temp.:can be neglected

THEMIS peer PDR Summaries 13 October, 2003 FGM Requirements (3) IN.FGM-4. The FGM digital resolution shall be less than 0.1nT IN.FGM-6. The FGM science range shall exceed 0-1000nT -FGM provides 0.01nT digital resolution independent of the external field due to digital magnetometer principle - The maximum feedback field (range) is about 32000nT - 24 bits per field component will be sent to the IDPU - 16 bits will be selected for transmission 10pT digital resolution if B < 320nT 160pT digital resolution if B > 2500nT 1.2nT digital resolution if B > 20000nT

THEMIS peer PDR Summaries 14 October, 2003 FGM Requirements (4) IN.FGM-7. The FGM frequency range shall exceed DC-1 Hz - FGM primary data rate is 128Hz (7.5ms measurement, 0.3ms feedback setting) -Further averaging will be done in the FGE FPGA and/or by the IDPU

THEMIS peer PDR Summaries 15 October, 2003 FGM-Mission Requirements (1) REQUIREMENTFGM DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. Lifetime has been considered in all aspects of FGM design (parts, performance degradation, etc). IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. Common Parts Buy for Instrument Payload. All parts screened for total dose. Radiation testing planned if TID is unknown (AD648) or has already been performed by TUBS (AD625, MIC4425). All FGE components under UCB control. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. Common Parts Buy for Instrument Payload. Most parts screened for SEE. Radiation testing planned if LET is unknown (AD625, MIC4425). All FGE components under UCB control. IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. FGM Sensor: 80g Allocated. FGS mass is 76 g. (Harness and FGE Board tracked with IDPU)

THEMIS peer PDR Summaries 16 October, 2003 FGM-Mission Requirements (2) -Needed supply voltages and currents based on VEX-MAG and bread board: +5V d & +2.5V d (FPGA & DAC) 10mA +8V a (excitation & amplifiers ) 50mA (30mA+20mA) -8V a (amplifiers) 20mA +/-5V a (ADC) 15mA -760mW if all voltages will be provided (+80/-0mW)  No EEE part with > 100mW power dissipation! REQUIREMENTFGM DESIGN IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. 900mW Allocated.

THEMIS peer PDR Summaries 17 October, 2003 FGM-Mission Requirements (3) REQUIREMENTFGM DESIGN IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. See further down IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. Calibration and verification facilities exist in Graz (IWF) and Braunschweig (TUBS). Detailed calibration procedure planned operating temperature range (sensor/electronics): –100°C / -20°C to +65°C / +45°C cold start (sensor/electronics): -100 °C / -50°C survival temperature range (sensor/electronics): –100°C / -50 °C to +65°C -FGM sensor qualified for +/-100°C (Rosetta, VenusExpress)

THEMIS peer PDR Summaries 18 October, 2003 FGM-Mission Requirements (4) REQUIREMENTFGM DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Control Plan. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan IN-19. All Instruments shall comply with all electrical specifications Compliance. THM-IDPU-001 Backplane Specification IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-106 FGM Interface Requirements Document (Internal # THM-FGM-DS- 0001 V1.3). Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-SYS-112 Probe-to-FGM Mag Boom ICD. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed.

THEMIS peer PDR Summaries 19 October, 2003 FGM-Peer Review Results 21 Findings: From No.1 - Jitter spec. of CLK8MHz should meet the FGM requirements (i.e. 10%) To No.21 – Magnetic control plan and S/C test in GSFC coil facility (under UCB control)  FGM team fully understands the findings and will take it into account during the upcoming instrument development process! 2 RFAs: RFA FGM-1: Magnetic CleanlinessStatus: UCB is working on it RFA FGM-2: Anti-Aliasing FilterStatus: FGM working on it –It was always planned to implement such a filter –Final filter spec is dependant on a trade-off between anti-aliasing, data decimation and impact on the quality of the de-spinning process.

THEMIS peer PDR Summaries 20 October, 2003 SCM Preliminary Design Review October 10, 2003 CETP / France

THEMIS peer PDR Summaries 21 October, 2003 8:30-9:00Introduction, SCM Overview and SpecificationsAlain Roux 9:00-9:30Mechanical Design : - antennas manufacturing - support SCM Christophe Coillot 9:30-10:00Electrical designChristophe Coillot Break 10:15-10:45Mechanical and Electrical Design :3D+ 10:45-11:15Mechanical and electrical designAbdel Bouabdellah 11:15-11:45Interface RequirementsAbdel Bouabdellah 11:45-12:00Power and Mass Summary : Objectives versus state of realization Bertrand Delaporte Lunch 1:30-2:151) Test 1) Pre-I&T at UCB 2) Spacecraft Integration Plan and Support 3) GSE provided and required : Bertrand Delaporte SCM-peer PDR agenda

THEMIS peer PDR Summaries 22 October, 2003 02:15-02:30Implementation ScheduleBertrand Delaporte 02:30-02:45 Parts and MaterialsChristophe Coillot 02:45-03:00Contamination control, safety and assuranceAbdel Bouabdellah Break 03:15-03:30SummaryAlain Roux / Olivier Lecontel 03:30-04:00Visit at CETP 04:00-05:00Splinter sessions 1. Review team assembly 2. ITAR/MOU and Import-Export licencing 3. Other UCB/CETP 05:00-05:30Recommendations from review teamReview Team SCM-peer PDR agenda

THEMIS peer PDR Summaries 23 October, 2003 REQUIREMENTSCM DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. SCM Sensor: 600g Allocated. Pre-amp: 220g Allocated. (Harness and DFB Board tracked with IDPU) IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. Pre-Amp: 90mW Allocated. IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. SCM-Mission Requirements

THEMIS peer PDR Summaries 24 October, 2003 REQUIREMENTFGM DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Control Plan. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan IN-19. All Instruments shall comply with all electrical specifications Compliance. THM-IDPU-001 Backplane Specification IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-107 SCM Interface Control Document (Internal # THM-SCM-SYS-ICD-0.1). Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-SYS-112 Probe-to-SCM Mag Boom ICD. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. SCM-Mission Requirements

THEMIS peer PDR Summaries 25 October, 2003 REQUIREMENTSCM DESIGN IN.SCM-1. SCM shall provide a critical test for the role of waves at substorm onset, in various models (together with EFI). Compliance. IN.SCM-2. SCM shall measure the 3D AC B-field from 1 Hz to 4kHz Compliance. IN.SCM-3. The SCM sensitivity shall be better than 1pT/Hz^1/2 @10Hz, and 0.1 pT/Hz^1/2 @1 kHz. Compliance. IN.SCM-4. The SCM DFT spectral range shall be in the range 16Hz to 4 kHz, transmitted as 32 steps with df/f ~ 25%. Compliance. IN.SCM-5. The transfer function of the SCM sensors (amplitude &phase) shall be known with an accuracy better than 5%. Compliance. IN.SCM-6. On each spacecraft the 3 magnetic antennas, shall be held orthogonal by a structure procured by CETP. Compliance. SCM-Sensor Requirements

THEMIS peer PDR Summaries 26 October, 2003 REQUIREMENTSCM DESIGN IN.BOOM-1. Mag Boom deployment shall be repeatable to 1 degree Compliance. IN.BOOM-2. Mag Boom stability shall be better than 0.1 degree (includes bus and boom components) Compliance. IN.BOOM-3. Mag Boom deployed stiffness shall be greater than 0.75Hz Compliance. IN.BOOM-4. Mag Boom shall be designed to be deployed between 2 and 15 RPM about the Probe's positive Z axis. Compliance. IN.BOOM-9. The SCM boom shall be approximately 1 meters long. Compliance. IN.BOOM-12. All deployed booms shall include TBD inhibits to prevent inadvertent release. Compliance. SCM Boom Requirements

THEMIS peer PDR Summaries 27 October, 2003 SCM-Peer Review Results Status of RFAs RFA1: -AC magnetic cleanliness Status - Main issue is solar cells rotation (non circular S/C). Magnetic modeling will be made to estimate spurious noise at SCM location, once the info on solar cell wiring is available. UCLA is conducting a mag-cleanliness program; they have the software to carry out this evaluation -CETP can help by providing a “sniffer”, to measure spurious noise from s/c, and from other instruments. Involves some extra cost.

THEMIS peer PDR Summaries 28 October, 2003 SCM-Peer Review Results RFA2: -Schedule problem with FM1/PA -Part list to be agreed with UCB Status: -delivery of FM1 together with FM2&3 on september 24 th ; agreed with UCB. -Final part list sent to UCB nov 10 th. RFA3: -Alignment budget Status : -Magnetic axis determined within 0.2% during tests at Chambon, once the antenna are mounted on their structure. -Main difficulty is stability/knowledge of boom axis.

THEMIS peer PDR Summaries 29 October, 2003 ESA/SST/EFI/IDPU/Booms/GBO -Peer Reviews (UCB Oct 15,16,17)

THEMIS peer PDR Summaries 30 October, 2003 ESA/SST/EFI/IDPU/Booms/GBO -Peer Review Agenda (UCB Oct 15,16,17)

THEMIS peer PDR Summaries 31 October, 2003 ESA/SST/EFI/IDPU/Booms/GBO -Peer Review Agenda (UCB Oct 15,16,17)

THEMIS peer PDR Summaries 32 October, 2003 ESA/SST/EFI/IDPU/Booms/GBO -Peer Review Agenda (UCB Oct 15,16,17) Day 3

THEMIS peer PDR Summaries 33 October, 2003 ESA Plasma Analyzer Instrument Preliminary Design Review Charles Carlson, Bill Elliot, Paul Turin, Jim Lewis University of California - Berkeley

THEMIS peer PDR Summaries 34 October, 2003 Overview Generic Subsystem Requirements & Specifications Heritage Design Overview Block Diagram Component Descriptions Mechanical and Thermal Mass and Power Schedule Issues

THEMIS peer PDR Summaries 35 October, 2003 REQUIREMENTESA DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. Lifetime has been considered in all aspects of ESA Design. System design and components are direct copy of FAST ESA (still fully functional after 7 years on orbit) IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. Common Parts buy for Instrument Payload. Lower radiation dose than FAST ESA has experienced without problem. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. FAST components were selected for SEE and latch-up immunity and are verified by flight history. IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. 2.0 kg Allocated. As built weight for equivalent FAST instrument is 1.92 kgm. IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. 2.0 W Allocated. As built power for equivalent FAST instrument is 1.75 Watt. IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. ESA is designed and will be tested to comply with the ICD requirements. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. ESA is designed and will be tested to comply with the ICD requirements. ESA-Mission Requirements

THEMIS peer PDR Summaries 36 October, 2003 REQUIREMENTESA DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Contamination Control Plan. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan IN-19. All Instruments shall comply with all electrical specifications Compliance. THM-IDPU-001 Backplane Specification. IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-105 ESA and SST Electronics Card (ETC) Specification. Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-SYS-101 IDPU/ESA-to-Probe ICD. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. ESA-Mission Requirements

THEMIS peer PDR Summaries 37 October, 2003 REQUIREMENTESA DESIGN IN.ESA-1. The ESA shall obtain partial moments of the 3D plasma electron and ion distributions in the magnetotail plasma sheet Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN.ESA-2. The ESA shall measure differences in velocity and ion pressure between probes in the magnetotail plasma sheet Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN.ESA-3. The ESA shall measure ion and electron distributions that are associated with the current disruption process Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. IN.ESA-4. The ESA shall be capable of measuring ion moments and differences of those moments in the magnetosheath and solar wind. Compliance. ESA will provide the ETC board with plasma measurement data sufficient for computing the required moments. Solar wind moments will be limited to a specific range of velocity and density consistent with instrument saturation. ESA-Science Requirements

THEMIS peer PDR Summaries 38 October, 2003 REQUIREMENTESA DESIGN IN.ESA-5. The ESA shall measure ions and electrons over an energy range of 10eV to 30 keV Compliance. Satisfied by design. IN.ESA-6. The ESA energy sampling resolution, dE/E, shall be better than 25% FWHM for ions and electrons Compliance. Satisfied by design. IN.ESA-7. The ESA shall be capable of measuring ion and electron energy flux of 10^4 to 10^9 keV/cm^2/s/Str/keV Compliance. Satisfied by design. IN.ESA-8. The ion ESA geometric factor shall be attenuated in the solar wind to avoid saturation. Compliance. High fluxes of solar wind ions will be accommodated by small area anodes in the equatorial view directions. IN.ESA-9. The ESA shall supply partial energy moments at one spin time resolution. Compliance. Satisfied by design. IN.ESA-10. The ESA shall have a 180 deg. elevation FOV with a minimum angular resolution of 22.5 deg. Compliance. Satisfied by design. IN.ESA-11. To resolve the solar wind, the ESA shall have a FOV with enhanced resolution of ~ 6 deg. Compliance. Satisfied by design. IN.ESA-12. The ESA shall produce measurements of particle distributions over the entire 4pi steradian field of view in one spin period. Compliance. Satisfied by design. IN.ESA-13. ESA calibration shall ensure <20% relative flux uncertainty (not including statistical uncertainty) over the ranges defined above. Compliance. Satisfied by on-orbit calibration of plasma density with wave measurements. ESA-Performance Requirements

THEMIS peer PDR Summaries 39 October, 2003 ESA-Peer Review Results Status of RFAs RFA: UCB-2 Monitor aging of calibration beam Already Done? RFA: UCB-3 Formalize nanomuscle test plan No attenuator on ESA; solar wind goals met with current anodes. No nanomuscle used at all now on ESA. RFA: UCB-4 Mass and power formal tracking Done by systems engineer; reported to GSFC. RFA: UCB-5 Establish program plans for test program Done by systems engineer. Verification and test plan draft submitted.

THEMIS peer PDR Summaries 40 October, 2003 SST Subsystem Preliminary Design Review Davin Larson, Thomas Moreau, Ron Canario, Robert Lee, Jim Lewis UCB

THEMIS peer PDR Summaries 41 October, 2003 Overview Solid State Telescope (SST) Requirements and Specifications Block Diagram Mechanical Design –Detectors –Collimation –Magnets –Attenuator (aka shutter, door) –Detector placement / FOV issues –Mass estimates Electrical Design –AFE – (Analog Front End) (aka: DFE) –ADC board (aka: DAP) –Power Estimates Testing and Calibration Schedule Issues

THEMIS peer PDR Summaries 42 October, 2003 REQUIREMENTSST DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. Lifetime has been considered in all aspects of SST design (parts, performance degradation, etc). Common Parts Buy for instrument payload. IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. All parts screened for total dose. Radiation testing planned if TID is unknown. (All major parts tested to 50 krad.) IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. Most parts screened for SEE. Radiation testing planned if LET is unknown. (DACs still unknown) IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. Sensor: 0.80 kg Allocated. Harness: 0.24 kg Allocated. (DAP Board tracked with IDPU) IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. DFE: 0.30 W Allocated DAP: 1.06 W Allocated. IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. DAP: –50 to 65 DFE: -65 to 100 IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. DAP: –30 to 40 DFE: -55 to 70 SST-Mission Requirements

THEMIS peer PDR Summaries 43 October, 2003 REQUIREMENTSST DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Contamination Control Plan. Budget for SST Magnets is <0.75nT @ 2 meters. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan. Box electrical isolated. IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan IN-19. All Instruments shall comply with all electrical specifications Compliance. THM-IDPU-001 Backplane Specification. IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-105 ESA and SST Electronics Card (ETC) Specification. Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-SYS-111 SST-to-Probe ICD. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. SST-Mission Requirements

THEMIS peer PDR Summaries 44 October, 2003 REQUIREMENTSST DESIGN IN.SST-1. The SST shall perform measurements of the tailward-moving current disruption boundary speed using the finite gyroradius technique Compliance. Provided by Full Distribution Functions (FDFs). IN.SST-2. The SST shall measure the time-of-arrival of superthermal ions and electrons of different energies emanating from the reconnection region to determine RX onset time. Compliance. 3 second time resolution of FDFs IN.SST-3. The SST shall obtain partial moments of the plasma electron and ion distributions in the magnetotail plasma sheet Compliance. Partial moments produce by ETC board. IN.SST-4. The SST shall obtain measurements of ion and electron distribution functions with one spin resolution (<10sec required) Compliance. Full distribution functions at 1 spin resolution obtained in burst mode. IN.SST-5. The SST shall measure energetic electron fluxes as close to Earth as 6RE geocentric, at all local times. Compliance. Attenuator lowers flux sufficiently to avoid saturation at this distance IN.SST-6. The SST shall measure energetic ions in the solar wind, at the magnetopause and in the magnetosheath. Compliance. SST-Science Requirements

THEMIS peer PDR Summaries 45 October, 2003 REQUIREMENTSST DESIGN IN.SST-7. The SST shall measure energetic particles over an energy range of 30-300keV for ions and 30- 100keV for electrons found in the magnetotail plasma sheet. Compliance. Electrons: ~25 keV to ~800 keV Ions: ~25 keV to ~2 MeV (possibly 6 MeV) IN.SST-8. The SST energy sampling resolution, dE/E, shall be better than 30% for ions and electrons. Compliance. Intrinsic energy resolution is ~6 keV with 1.5 keV binning. IN.SST-9. The SST shall be capable of measuring differential energy flux in the range from: 10^2 to 5x10^6 for ions; 10^3-10^7 for electrons (keV/cm2-s -st- keV) whilst providing adequate counts within a 10 second interval. Compliance. Max counting rate estimated at 50,000 cps (per detector). Two geometric factors: G1 ~ 0.1 cm2-ster G2 = G1/64. IN.SST-10. The SST shall measure over 90 deg. in elevation with a minimum resolution of 45 deg. Compliance. Elevation: +/- 60 deg, Resolution:~37 deg. IN.SST-11. The SST shall have an azimuthal resolution of 45 deg. Compliance. Azimuthal resolution = 22.5 deg IN.SST-12. The SST shall supply the high energy partial moments at one spin time resolution. Compliance. Performed by ETC board IN.SST-13. SST calibration shall ensure <20% relative flux uncertainty over the ranges defined above. Compliance. Measured pre-flight; Verified by in-flight calibration. SST-Performance Requirements

THEMIS peer PDR Summaries 46 October, 2003 SST-Peer Review Results Status of RFAs RFA: UCB-3 Nanomuscle Development RFA: UCB-4 Mass / Power RFA: UCB-5 Mechanism Life Cycle Testing RFA: UCB-6 SST Operating Temperature RFA: UCB-7 SST Reconsider the following design decisions: a.Changing the sweep magnet to better exclude 250--400 keV electrons. - Already Done. b.Operating the detectors at an average temperature 0 C instead of 25 C. - In progress. c.Increasing the ion energy range to include the 6 MeV calibration point. – This is current plan- However there remains strong probability of reducing to ~2 MeV to maximize prime science. d.Use of high-Z materials (tungsten) near the detectors should be evaluated in terms of locally generating bremsstrahlung x-ray background. This has been modeled and current plans are to use Be-Cu knife edges. e.Sun glints not only temporarily blind the particle detectors, but preamp can saturate and require additional time to recover. This effect to be measured, especially with their thinner dead layers. – To be measured using Breadboard and ETU

THEMIS peer PDR Summaries 47 October, 2003 Magnetometer Booms (MAGS) Preliminary Design Review Hari Dharan Space Sciences Laboratory University of California at Berkeley

THEMIS peer PDR Summaries 48 October, 2003 Outline Mag Booms Overview Requirements & Specifications Mechanical Design –Deployment Simulation and Results –Frangibolt Assembly –Elbow Hinge Design –Base Hinge Design –Tube Design Thermal Considerations Mass Mag Boom Length Harness Layout Fabrication and Assembly Plan Parts and Materials Test Plan Schedule

THEMIS peer PDR Summaries 49 October, 2003 Mag. Boom Requirements THEMIS MISSION DESIGN REQUIREMENTS Mag. Boom deployment shall be repeatable to 1 degree Mag. Boom stability shall be better than 0.1 degrees. Mag. Boom deployed stiffness shall be greater than 0.75 Hz Mag. Booms shall be designed to be deployed between 0 and 15 RPM The SCM boom shall be at least 1 meter long. The FGM boom shall be at least 2 meter long.

THEMIS peer PDR Summaries 50 October, 2003 Mag. Boom Requirements GENERAL DESIGN REQUIREMENTS Safety and Safety Factors (MIL-STD-1522, EWR-127-1; P-10) Design Margins and Safety Factors (NASA-STD-5001; P-11) Stress Corrosion Cracking Sensitivity (MSFC-STD-3029; P-12) Composite & Bonded Joint Proof Loads (NASA-STD-5001; P-14) Materials Outgassing: 1% TML, 0.1% VCML (M-31, -32, -33) Dissimilar Materials & Electrolyte Corrosion (P-15) THEMIS UNIQUE DESIGN REQUIREMENTS Magnetic Cleanliness Plan (M-26, -27, -28) Electrostatic Cleanliness Plan (M-29, -30) Contamination Control Plan (M-31, -32, -33)

THEMIS peer PDR Summaries 51 October, 2003 REQUIREMENTBOOM DESIGN IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. FGM Boom: 1.27kg Allocated. SCM Boom: 0.68kg Allocated. IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. Frangibolt: ~26W transient IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Control Plan. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan MagBoom Compliance to: Mission Requirements

THEMIS peer PDR Summaries 52 October, 2003 REQUIREMENTBOOM DESIGN IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. THM-SYS-112 Probe-to-FGM Mag Boom ICD. THM-SYS-113 Probe-to-SCM Mag Boom ICD. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. MagBoom Compliance to: Mission Requirements #2

THEMIS peer PDR Summaries 53 October, 2003 REQUIREMENTBOOM DESIGN IN.BOOM-1. Mag Boom deployment shall be repeatable to 1 degree Compliance. IN.BOOM-2. Mag Boom stability shall be better than 0.1 degree (includes bus and boom components) Compliance. IN.BOOM-3. Mag Boom deployed stiffness shall be greater than 0.75Hz Compliance. IN.BOOM-4. Mag Boom shall be designed to be deployed between 2 and 15 RPM about the Probe's positive Z axis. Compliance. IN.BOOM-8. The FGM boom shall be approximately 2 meters long. Compliance. IN.BOOM-9. The SCM boom shall be approximately 1 meters long. Compliance. IN.BOOM-12. All deployed booms shall include an inhibit to prevent inadvertent release. Compliance. MagBoom Compliance to: Boom Requirements

THEMIS peer PDR Summaries 54 October, 2003 Heritage Design construction, and operation based on FAST and Lunar Prospector magnetometer booms Requirements All requirements allocated System Performance Budget, Error Budget Addressed via IN.BOOM requirements in coordination with Swales mechanical group Margins Torque ratio of >3:1 maintained in all moving parts design, to be verified in test program Analytical SF >1.4 x limit loads for ultimate failure modes for metallic components, >2.0 for composite components Descope Plans SCM not necessary for minimum science MagBooms: Heritage and compliance philosophy

THEMIS peer PDR Summaries 55 October, 2003 Electric Field Instrument (EFI) Engineering Peer Review Overview Dr. John W. Bonnell and the THEMIS EFI Team Space Sciences Laboratory University of California - Berkeley

THEMIS peer PDR Summaries 56 October, 2003 Overview

THEMIS peer PDR Summaries 57 October, 2003 REQUIREMENTEFI DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime. Compliance. Lifetime has been considered in all aspects of EFI and DFB design (parts, performance degradation, etc.). IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. Common Parts Buy for Instrument Payload. All parts screened for total dose. Radiation testing planned if TID is unknown. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up. Compliance. Common Parts Buy for Instrument Payload. All parts screened for total dose. Radiation testing planned if LET is unknown. DFB design includes latchup mitigation circuits on ADCs, inclusion contingent upon results of LTC1604 radiation testing. EFI-Mission Requirements

THEMIS peer PDR Summaries 58 October, 2003 REQUIREMENTEFI DESIGN IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. SPB: 1.88 kg Allocated; 1.92 kg CBE (CAD model). AXB: 2.30 kg Allocated; 2.00 kg CBE (CAD model). (Harness, BEB and DFB tracked with IDPU) IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. Preamps: 0.09 W Allocated; 0.07 W CBE (BB). BEB: 1.76 W Allocated; 1.67 W CBE (BB). DFB: 1.00 W Allocated; 0.86 W CBE (modeling). IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. SPB/AXB ICDs signed off. Verification by Environmental Test planned. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. SPB/AXB ICDs signed off. Verification by Environmental Test planned. Special thermal shock testing of preamp ETU planned. EFI-Mission Requirements

THEMIS peer PDR Summaries 59 October, 2003 REQUIREMENTEFI DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Control Plan. Budget for EFI Magnets (Boom Motors) is <0.75nT @ 2 meters. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. Design, fabrication, and testing in accordance with THM-SYS-003 Electrostatic Cleanliness Plan. IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. Design and fabrication in accordance with THM-SYS-004 Contamination Control Plan. IN-19. All Instruments shall comply with all electrical specifications Compliance. Design in accordance with THM-IDPU- 001 Backplane Specification (BEB, DFB). IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. THM-SYS-103 DFB-to-IDPU ICD signed off. THM-SYS-104 BEB-to-IDPU ICD signed off. Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD. Compliance. Both THM-SYS-108 Probe-to-EFI Radial Booms ICD and THM-SYS-109 Probe-to-EFI Axial Booms ICD are signed off. Verification Matrices to be completed. IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Spec. Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft. Verification matrix to be completed. EFI-Mission Requirements

THEMIS peer PDR Summaries 60 October, 2003 REQUIREMENTEFI DESIGN IN.EFI-1. The EFI shall determine the 2D spin plane electric field at the times of onset at 8-10 Re. Compliance. Via compliance with IN.EFI-5 and -13. IN.EFI-2. The EFI shall determine the dawn/dusk electric field at 18-30 Re. Compliance. Via compliance with IN.EFI-5 and -13. IN.EFI-3. The EFI shall measure the 3D wave electric field in the frequency range 1-600Hz at the times of onset at 8-10 Re. Compliance. Via compliance with IN.EFI-6, -8, -9, - 10, and –11. IN.EFI-4. The EFI shall measure the waves at frequencies up to the electron cyclotron frequency that may be responsible for electron acceleration in the radiation belt. Compliance. Via compliance with IN.EFI-6, -8, -9, - 10, and –11. EFI-Science Requirements

THEMIS peer PDR Summaries 61 October, 2003 REQUIREMENTEFI DESIGN IN.EFI-5. The EFI shall measure the 2D spin plane DC E-field with a time resolution of 10 seconds. Compliance. On-board spin-fit of spin plane E-field at 3-s (one-spin) resolution. IN.EFI-6. The EFI shall measure the 3D AC E-field from 1 Hz to 4kHz. Compliance. 3-axis E-field measurement sampled at 8 ksamp/s. See AC Error Budget. Verified through Calibration. IN.EFI-7. The EFI shall measure the Spacecraft Potential with a time resolution better than the spin rate (3 seconds; from ESA to compute moments). Compliance. On-board spin-avg’d sphere potentials at 3-s (spin-rate) resolution; EFI data rate allocation includes single spheres at ¼-rate of E-field data. IN.EFI-8. The EFI DFT Spectra Range shall be 16Hz to 4kHz, with df/f~25%. Compliance. Spectral products from DFB cover 8 Hz to 8 kHz at 5%, 10%, or 20% BW (16, 32, or 64 bins) IN.EFI-9. The EFI shall measure DC-coupled signals of amplitude up to 300 mV/m with 16-bit resolution. Compliance. Analog gain and ADC resolution of DFB set accordingly. Verified through Calibration. IN.EFI-10. The EFI shall measure AC-coupled signals of amplitude up to 50 mV/m (TBR) with 16-bit resolution. Compliance. Analog gain and ADC resolution of DFB set accordingly. Verified through Calibration. EFI-Performance Requirements

THEMIS peer PDR Summaries 62 October, 2003 REQUIREMENTEFI DESIGN IN.EFI-11. The EFI noise level shall be below 10 -4 (mV/m)/Hz 1/2. Compliance. Low-noise preamp chosen (OP-15); good analog design practices throughout preamp, BEB and DFB; CBE is 3x10 -5 on AXB, 3x10 -6 on SPB. Verified through ETU testing. IN.EFI-12. The EFI HF RMS (Log power) measurement shall cover 100-500 kHz with a minimum time resolution of the spin rate (on-board triggers). Compliance. CBE of EFI response has gain of 0.8 out to 1 MHz; DFB provides HF-RMS at 1/16 to 8 samp/s. IN.EFI-13. The EFI shall achieve an accuracy better than 10% or 1 mV/m in the SC XY E-field components during times of onset. Compliance. See DC Error Budget Discussion. EFI-Performance Requirements

THEMIS peer PDR Summaries 63 October, 2003 REQUIREMENTEFI DESIGN DFB FUNCTIONAL REQUIREMENTS IN.DPU-36. The IDPU DFB shall provide an FFT solution for determining the parallel and perpendicular components of E and B in both fast survey and burst modes and produce spectra for each quantity separately. Compliance. DFB design includes FPGA-based projection (E dot B, E cross B) and FFT solutions. Verified through Test and Calibration of ETU. IN.DPU-37. The IDPU DFB shall integrate FGM digital data and EFI data to produce E·B Compliance. DFB design includes FPGA-based projection ( E dot B, E cross B) solutions. Verified through Test and Calibration of ETU. EFI Board Requirements

THEMIS peer PDR Summaries 64 October, 2003 REQUIREMENTEFI DESIGN BEB FUNCTIONAL REQUIREMENTS IN.DPU-38. The IDPU BEB shall provide sensor biasing circuitry, stub and guard voltage control, and boom deployment for the EFI. Compliance. The BEB design provides 3 independent bias channels per sensor (BIAS,GUARD,USHER) and one shared bias channel for the SPB sensors (BRAID). Boom deployment is provided through the IDPU/PCB and DCB. IN.DPU-39. The IDPU BEB shall distribute a floating ground power supply to the EFI sensors. Compliance. The BEB design provides 6 independent floating grounds to the LVPS, and distributes the derived +/-10-V analog supplies to the six EFI sensors. IN.DPU-40. The IDPU BEB shall generate six independent BIAS, GUARD and USHER voltages with an accuracy of 0.1% for distribution to the EFI sensors. Compliance. The BEB design includes matched gain-setting components, along with >12-bit DAC, allowing accuracy of better than 0.1%; Verified through Test and Calibration of ETU. EFI Board Requirements

THEMIS peer PDR Summaries 65 October, 2003 REQUIREMENTEFI DESIGN IN.BOOM-5a. Deployed EFI Axials shall be repeatable and stable to  = 1 degree and  L/L = 1%. Compliance. Adequate stiffness and angular alignment of AXB stacers and deploy system included in design; verified by testing of ETU. IN.BOOM-5b. Deployed EFI Radials shall be repeatable and stable to  = 1 degree and  L/L = 1%. Compliance. Proper SPB cable design (stiffness, tempco) along with std. Cable winding procedures included in design; verified by testing of ETU. IN.BOOM-6. EFI Axial Booms shall be designed to be deployed between 2 and 25 RPM about the Probe's positive Z axis. Compliance. Adequate stiffness and angular alignment of AXB stacers included in design; verified by testing of ETU. IN.BOOM-7. EFI Radial Booms shall be designed to be deployed between 2 and 25 RPM. Compliance. Adequate strength margins on cable included in design; verified by proof-loading of cable and testing of ETU. IN.BOOM-8. EFI Axial Booms deployed stiffness shall be greater than 0.75 Hz (1 st mode). Compliance. Part of AXB stacer spec; verified by Testing of ETU. IN.BOOM-12. All deployed booms shall include TBD inhibits to prevent inadvertent release. Compliance. Test/Enable plugs included in design. Red tag door (SPB) and tube (AXB) covers. EFI Boom Requirements

THEMIS peer PDR Summaries 66 October, 2003 EFI-Summary of EPR Findings Radial Boom design ( 1,2,3,9; Draft findings, 3 Nov 2003 ): Dynamic stability issues (spin/trans MOI ratio) (Bus EPR) Dual-length/longer-length designs Axial Boom design ( 6,10 ): Deploy force margin Length vs. noise margin, whip vs. sphere sensors. Attitude information and jitter requirements ( 14 ). Miscellaneous mechanical findings ( 15,18,5 ): Deploy sequence modeling. Boom deployment temperature. SPB miter gear life testing. Hot parts and thermal stresses Gain and Filter Specifications of EFI and SCM on DFB ( 4,8,12 ). BEB FPGA specification and programming ( 20 ). Preamp electro-mechanical design ( 11 ). Electrostatic Cleanliness Specification (RFA UCB-8)( 7,17 ). EMI/EMC Specification (RFA UCB-9)( 13 ). Detailed I&T plan development (RFA UCB-10)( 19 ).

THEMIS peer PDR Summaries 67 October, 2003 EFI-EPR Findings; Radial Booms Dynamic stability issues: Bus and Instrument team analysis of dynamic stability not in accord; question is proper spin/transverse MOI ratio for non-rigid boom systems on THEMIS. Swales analysis indicates shorter AXB (60%) or longer SPB required to achieve stable configuration (Bus EPR finding). Longer-length/Dual-length designs (science-driven): 56-m (2x(25+3)m system) tip-to-tip SPB possible with current mechanical design. Direct improvement in DC error budget (30%). Allows for dual-length (21/28 m) system that would allow the detection of ES wake effects (not mission critical, however). Mass hit (56 g/SPB) for 7-m cable addition; fuel hit (~60%, 452 g increase) for final spin up. Resolution: Must be resolved by Jan ’04 (EFI F1 Cable Assy); Cable Assy schedule margin allows push back to Apr ’04, if necessary. Dynamic stability analysis is ongoing at Swales and UCB.

THEMIS peer PDR Summaries 68 October, 2003 EFI-EPR Findings;Axial Booms Deploy force margin and AXB length repeatability: AXB design may not have enough deploy force margin to ensure dL/L = 1% repeatability of deploy length. Resolution: AXB ETU testing (Feb ’04). Length vs. Noise Margin; whip vs. sphere sensor response Current AXB length (~9-m effective, 10-m tip-to-tip) allows only factor of 3 S/N margin at 4 kHz (CBE of system noise level). SC perturbations will strongly affect DC E-field in AXB (several mV/m, dependent upon SC potential (plasma conditions). AXB whip sensor may have different response para/perp to B than SPB sphere+wire sensor. Resolution: AXB length can not be reduced significantly without compromising 3D AC measurement. AXB lengths will be trimmed based on simulation results to reduce DC offset due to SC potential (final length Feb ’04 (AXB F1 Mach)). Literature on antenna response to be investigated to determine significance of whip vs. sphere effect (no mitigation planned; different capacitance of SPB and AXB sensors already known, and part of electrical Calibration plan).

THEMIS peer PDR Summaries 69 October, 2003 EFI-EPR Findings—Attitude Attitude knowledge and jitter requirements are modest, and achievable by Bus and Instrument designs. 5.6 degree (10%) knowledge required; better than 1 degree (0.5%) achieved via post-processing of FGM and EFI data. Better than 3-degree accuracy and jitter in spin phase required for accurate on- board spin fits of E-field data; current IDPU design provides much better than 0.1 degrees. Alignment requirements more stringent, driven by DC error budget of SPB. Opposing pairs of SPB booms must align within 1 degree to bring systematic error due to differential photoemission below 1 mV/m for nominal biasing scheme and sphere sheath impedances.

THEMIS peer PDR Summaries 70 October, 2003 EFI-EPR Findings; Misc. Mech. UCB should initiate kinematic and dynamic modeling of the boom deploy sequences. Resolution: Kinematic model of boom deploy already exists (Th_booms3d.xls; D. Pankow) at UCB as tool for understanding timing, spin-up requirements, mechanical loads, boom/SC modes, coriolis displacements, etc. Resolution: Algor product will be taken under advisement as part of on-going resolution of dynamic stability question (see Radial Booms; Jan ‘04). Boom deployment temperature range should be defined. Resolution: Boom deployment temperature range will be defined as part of I&T test flow (Dec. ’03-Jan. ‘04). SPB miter gear life testing under worst-case load required. Resolution: Such testing will be included in SPB I&T test plan (Dec ’03 – Jan ’04).

THEMIS peer PDR Summaries 71 October, 2003 EFI-EPR Findings—Hot Parts High-dissipation (> 100 mW) parts should be identified, and junction temperature coefficients tabulated. Resolution: Data will be provided to thermal analysis as required.

THEMIS peer PDR Summaries 72 October, 2003 EFI-EPR Findings; Gain/Filter DC/AC-coupled dynamic range and solitary waves Large-amplitude (>=100 mV/m) solitary waves have been observed at frequencies from 1-1000 Hz on Polar and Cluster in the THEMIS observation region. Such waves will saturate the AC-coupled (10 Hz-6 kHz) E-field channels with a dynamic range of +/- 50 mV/m. Resolution: Other channels can handle the large-amplitude events, although not simultaneously. DC-coupled (0-4 kHz) channels have a dynamic range of +/- 300 mV/m. Dc-coupled sphere/whip voltages have +/-60-V range (3 V/m on SPB, ~13 V/m on AXB). AC-coupled gain may be reduced to allow higher rate sampling of large-amplitude signals (TBR, Nov-Dec ’03, DFB ETU design). Filter specifications SCM channels use Butterworth, EFI uses Bessel. Difference means non-trivial phase differences and time-domain responses over entire 0-4 kHz range, maximizing between 1-4 kHz, preventing direct comparison of time-domain signals. Resolution: Trade between filter types underway; component value issue; active filter topology doesn’t change (TBR, Nov-Dec ’03, DFB ETU design).

THEMIS peer PDR Summaries 73 October, 2003 EFI-EPR Findings; BEB FPGA BEB FPGA specification and programming Resolution: BEB FPGA requirements are modest and now well-defined (CDI interface, DAC control, Analog housekeeping), and common to most IDPU boards, allowing FPGA programmer (R. Abiad, UCB) to work on design and programming within BEB ETU schedule (Build/Test, Dec ’03).

THEMIS peer PDR Summaries 74 October, 2003 EFI-EPR Findings—Preamp Bootstrapping and guarding of preamp inputs Bootstrapping and guarding of preamp electronics in the current electromechanical design should be reviewed. Potentials of all conductors need to be defined (can, shields, etc.). Resolution: Current design does not include input guard, based on estimated input capacitance of preamp enclosure. Preamp ETU Assy and Test begins early Dec ’03 to characterize input capacity, and allow for changes and re-evaluation before FLT fabrication begins (Jan ’04).

THEMIS peer PDR Summaries 75 October, 2003 EFI-EPR Findings—ESC Electrostatic Cleanliness Specification and Enforcement Resolution: Rev. B of THM-SYS-003 Electrostatic Cleanliness Plan has been posted for review and will be signed off in Nov ’03. It includes a complete specification of electrostatic cleanliness requirements as well as verification procedures. The specification sets a 1-V potential uniformity requirement under an 8 nA/cm 2 current density, with 0.1-V potential uniformity as a goal (see DC Error Budget for discussion).

THEMIS peer PDR Summaries 76 October, 2003 EFI- EPR Findings—EMI/EMC Electromagnetic Interference/Cleanliness Specification Resolution: A Draft of the THEMIS EMI/EMC Specification has been posted for review and will be signed off in TBD. This specification is modeled on that for the FAST mission, adapted to the instrument properties on THEMIS (SCM/EFI system noise levels and expected wave amplitudes). Testing and verification of compliance with EMI/EMC TBD, and requires some work, due to low frequencies of interest (0-4 kHz).

THEMIS peer PDR Summaries 77 October, 2003 EFI-EPR Findings—I&T Plan I&T test flow needs to be defined to include development, ETU, qualification and acceptance testing. Resolution: An EFI I&T plan will be developed in Dec ’03 to support qualification and acceptance testing of the EFI ETU in Jan-Mar ’04.

THEMIS peer PDR Summaries 78 October, 2003 THEMIS IDPU Preliminary Design Review October 16, 2003

THEMIS peer PDR Summaries 79 October, 2003 Agenda

THEMIS peer PDR Summaries 80 October, 2003 REQUIREMENTIDPU DESIGN IN-1. The Instrument Payload shall be designed for at least a two-year lifetime Compliance. Lifetime has been considered in all aspects of IDPU design (parts, performance degradation, etc). IN-2. The Instrument Payload shall be designed for a total dose environment of 33 krad/year (66 krad for 2 year mission, 5mm of Al, RDM 2) Compliance. Common Parts Buy for Instrument Payload. All parts screened for total dose. Radiation testing planned if TID is unknown. IN-3. The Instrument Payload shall be Single Event Effect (SEE) tolerant and immune to destructive latch-up Compliance. Common Parts Buy for Instrument Payload. Most parts screened for SEE. Radiation testing planned if LET is unknown. IDPU-Lifetime and Radiation Some parts for core IDPU boards planned for testing, replacements identified

THEMIS peer PDR Summaries 81 October, 2003 REQUIREMENTIDPU DESIGN IN-7. No component of the Instrument Payload shall exceed the allocated mass budget in THM-SYS-008 THEMIS System Mass Budget.xls Compliance. IDPU CBE is 5.0 kg. Allocated is 5.31 kg. Provides 6.3% contingency. IDPU-Resource Budgets - Mass From THM-SYS-008 System Mass Budget:

THEMIS peer PDR Summaries 82 October, 2003 IDPU-Resource Budgets - Power REQUIREMENTIDPU DESIGN IN-9. No component of the Instrument Payload shall exceed the power allocated in THM-SYS-009 THEMIS System Power Budget.xls Compliance. IDPU CBE is 9.10 W. Allocated is 11.83 W. Provides 30% contingency. From THM-SYS-009 System Power Budget:

THEMIS peer PDR Summaries 83 October, 2003 IDPU-Interface Requirements IDPU Core Systems THM-IDPU-001 Backplane Specification Rev ISigned Off THM-DCB-001 Digital Control Board Specification (V0.4)Rev DSigned Off THM-LVPS-001 Low Voltage Power Supply SpecificationDraftIn Review THM-PCB-001 Power Control Board SpecificationRev AIn Review THM-FSW-001 Flight Software Requirements-Signed Off THM-FSW-002 Flight Software Specification-In Review IDPU Instrument Boards THM-SYS-103 EFI Digital Fields Board-to IDPU ICDRev BSigned Off THM-SYS-104 EFI Boom Electronics Board-to-IDPU ICDRev BSigned Off THM-SYS-105 ESA and SST Electronics Card Spec (ICD)Rev AIn Review THM-SYS-106 FGM I/F Requirement Document (ICD)Rev BSigned Off THM-SYS-107 SCM Interface Control Document (ICD)Rev -Signed Off IDPU to Probe Interface THM-SYS-101 IDPU/ESA-to-Probe ICDRev FSigned Off REQUIREMENTIDPU DESIGN IN-19. All Instruments shall comply with all electrical specifications Compliance. Backplane Specification signed off. Core System Specifications in review. IN-20. The Instrument Payload shall be compatible per IDPU-Instrument ICDs Compliance. Most Instrument-to-IDPU ICDs signed off. Verification Matrices to be completed. IN-21. The Instrument Payload shall be compatible per the IDPU-Probe Bus ICD Compliance. IDPU/ESA-to-Probe ICD signed off. Verification Matrices to be completed.

THEMIS peer PDR Summaries 84 October, 2003 REQUIREMENTIDPU DESIGN IN-13. The Instrument Payload shall survive the temperature ranges provided in the ICDs Compliance. IDPU/ESA-to-Probe ICD signed off. Verification by Environmental Test planned. IN-14. The Instrument Payload shall perform as designed within the temperature ranges provided in the ICDs Compliance. IDPU/ESA-to-Probe ICD signed off. Verification by Environmental Test planned. IDPU-Thermal Heat Transfer Conduction: IDPU thermally coupled to bottom deck using ChoTherm gasket Radiation: IDPU surfaces covered with low ε VDA tape or blankets ESA conducts heat away and radiates it to space Temperature Limits versus Predictions: Predictions for Swales Worst-case hot/cold Average operating around 30°C Monitoring and Control Probe Bus monitors interface temperature for survival Probe Bus provides two heater services: primary service thermostat closes at -23°C secondary service thermostat closes at -28°C IDPU provides additional instrument thermisters, heater control if needed Survival (°C) Predictions (°C) Margin (°C) Eclipse-Op Science-OpColdHotColdHot -50-3040+65-1636144

THEMIS peer PDR Summaries 85 October, 2003 REQUIREMENTIDPU DESIGN IN-16 The Instrument Payload shall comply with the Magnetics Cleanliness standard described in the THEMIS Magnetics Control Plan Compliance. THM-SYS-002 Magnetics Contamination Control Plan reviewed. Design guidelines will be followed (i.e. non-magnetic connectors, power cables, electronic parts). For IDPU subsystem, switching frequencies of power converters is only issue. Frequency Management Plan is planned. IN-17 The Instrument Payload shall comply with the THEMIS Electrostatic Cleanliness Plan Compliance. THM-SYS-003 Electrostatic Cleanliness Plan reviewed. No issues for IDPU subsystem. IN-18 The Instrument Payload shall comply with the THEMIS Contamination Control Plan Compliance. THM-SYS-004 Contamination Control Plan reviewed. Attention to cleanliness levels will be maintained, board and harness bake-out planned. IDPU-Contamination

THEMIS peer PDR Summaries 86 October, 2003 REQUIREMENTIDPU DESIGN IN-23 The Instrument Payload shall verify performance requirements are met per the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft has been reviewed. Verification matrix to be completed. IN-24 The Instrument Payload shall survive and function prior, during and after exposure to the environments described in the THEMIS Verification Plan and Environmental Test Specification Compliance. THM-SYS-005 Verification Plan and Environmental Test Specification preliminary draft has been reviewed. Verification matrix to be completed. IDPU-Verification and Test CPT(6) -45,55 -40,50

THEMIS peer PDR Summaries 87 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-1 The IDPU shall receive commands from the C&DH Subsystem via a 38.4 kbaud bi-directional interface Compliance. Ref IN.FSW-1: FSW Controls DMA Channel. Input string length = 1024 bytes (293 ms). Up to 8 stored commands and uplink commands. FSW executes commands at 64 Hz. Total rate regulated by Ops. Ref IN.DCB-1: Commands arrive via UART (38.4Kbaud) at 1Kbytes/sec +header & checksum IN.DPU-2. The IDPU shall send telemetry to the C&DH Subsystem via a 38.4 kbaud bi-directional interface Compliance. Ref IN.FSW-2: FSW Controls DMA Channel. Output string length = 150 bytes SOH&FGM (43ms). Ref IN.DCB-2: “Low-speed” telemetry transmitted via UART (38.4Kbaud). SOH and FGM engineering data (total of ~150bytes/sec). IN.DPU-3. The IDPU high speed interface (science data) to the C&DH Subsystem shall be at multiple fixed (commandable) rates from at least 1 kbps to 2 Mbps Compliance. Ref IN.FSW-3: FSW Controls DMA Channel with Packet Address and Length. Allows variable packet lengths. Fixed 2 MHz output and 1066 bytes/frame. Implies Data Rate of 200 frames/sec, and Packets average frame length. Ref IN.DCB-3: “High-speed” telemetry at 2 Mbps Science data, CCSDS packetization as described in THM-SYS-115 Telemetry Format Spec, transmission to BAU as described in THM-SYS-101 ICD. IN.DPU-21. The IDPU shall provide FGM telemetry to the Probe C&DH at a sample rate of 1 Hz. Compliance. Ref IN.FSW-21: FSW FGM.A module provides 1 time-tagged vector in a packet each sec. IDPU-Data Rates

THEMIS peer PDR Summaries 88 October, 2003 IDPU-Compression REQUIREMENTIDPU DESIGN IN.DPU-5. The IDPU shall provide loss-less data compression (as required) for all instrument data Compliance. Ref IN.FSW-5: FSW will use Differencing & Huffman2x4 algorithms as simulated and described in technical notes. Ref M-50: Downlink schedule analysis assumes 1.5x Multiple Algorithms Available (ref. thm_fsw_901_Compression) Huffman4 Delta Modulation Combined Delta Mod/Huffman Run Length not effective on this data Numerous Studies of Compression Algorithm Performance Used Cluster Flight Data Similar Instrumentation, Expected Signal Levels Similar Data Volumes Achieved appx 1.5 compression without being Adaptive High Rate (Burst) sampling Compresses > 2 Performance Studies of Non Adaptive Compressors Huffman4x2 Algorithm 21 KB/sec Delta Modulation Algorithm 11-14 KB/sec Entire Memory Compressed in 1-2 hours

THEMIS peer PDR Summaries 89 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-4. The IDPU shall be able to provide a real- time engineering data stream at the minimum data rate possible (1kbps) Compliance. Ref IN.DCB-2: SOH and FGM engineering data (total of ~150bytes/sec). Ref IN.C&DH-31: Downlink TLM filtered to 1 kbps IN.DPU-5. The IDPU shall provide loss-less data compression (as required) for all instrument data Compliance. Ref IN.FSW-5: FSW will use Differencing & Huffman2x4 algorithms as simulated and described in technical notes. Ref M-50: Downlink schedule analysis assumes 1.5x IN.DPU-6. The IDPU shall provide sufficient storage for all instrument science and housekeeping telemetry in SRR when not in ground contact: 750Mbits/orbit uncompressed + 1 day for contingency Compliance. Ref IN.FSW-6: FSW will pack instrument data into fixed 4KB blocks in the SRR. With the SSR maximum of 204.8MB, software must effectively store 128% of 93.75MB = 117MB (57% of capacity). Ref IN.DCB-7: SRR Provides 256Mbytes of raw SDRAM. Upper quadrant is devoted to ECC. IN.DPU-7. The IDPU shall be capable of playing back data upon command during ground contact (pointer from operators) Compliance. Ref IN.FSW-7: FSW will provide memory map and commands to allow a jam of the telemetry output pointer. IN.DPU-8. The IDPU shall provide the capability to re-transmit the SSR contents Compliance. Ref IN.FSW-8: FSW will provide memory map and commands to allow a jam of the telemetry output pointer. IN.DPU-9. The IDPU shall not erase instrument housekeeping telemetry from memory unless commanded to do so Compliance. Ref IN.FSW-9: FSW will keep instrument housekeeping buffered separately and will not allow overwrites. IDPU-Data Storage

THEMIS peer PDR Summaries 90 October, 2003 IDPU-Memory Resources SDRAM Functions SSR Science Data Storage Upper quadrant is devoted to ECC PROM Functions EEPROM Load Uplink Support Basic Functions EEPROM Functions One-Time Events Test Programs Initialization Parameters Science Upgrades RAM Functions Holds Code Image in RAM (8-12K) Max of Prior Projects appx 6K (HESSI 2.5K, Cluster 3.5K, FAST 5.8K) Required vs. Design 187.5MB Required (750Mbits/orbit + 1 day contingency = 1500Mbits = 187.5MB) / 256MB 3D-Plus SDRAM 8K PROM Required / 8K Ratheon R29793 Boot ROM 64K EEPROM Required / 128K Maxwell 28C011 EEPROM 14-18K RAM Required / 128K Honeywell 6228 (32K Directly Addressable,128K Page Addressable)

THEMIS peer PDR Summaries 91 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-10. The IDPU shall validate commands prior to execution Compliance. Ref IN.FSW-10: Parity checked. Command code. IN.DPU-11. The IDPU shall implement autonomous fault protection features Compliance. Ref IN.PCB-1: Current limited switches on the PCB isolate the DCB and PCB services from the Instrument Payload power services Ref IN.BKP-1: Backplane routes power independently to instrument electronics Ref IN.FSW-11: FSW will implement. However, no ICDs have identified any required features. IN.DPU-12. The IDPU shall enable all autonomous functions to be initiated and disabled by ground command Compliance. Ref IN.FSW-12: FSW provides enable bits for autonomous functions so that these functions can be disabled in favor of future uplinked software. IN.DPU-14. The IDPU shall provide the capability to upload or modify Instrument flight software Compliance. Ref IN.FSW-14: FSW will include Load, Dump and Execute commands. See LD.A IDPU-Fault Protection

THEMIS peer PDR Summaries 92 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-15. The IDPU shall accommodate continuous instrument data governed by overall system mode Compliance. Data description by modes (slow/fast survey, particle/wave burst) for all instruments are described in Instrument-to-IDPU ICDs. Ref IN.FSW-15: FSW TRG.A will have a direct command to set the mode and also operate in automatic mode, selecting the best mode. IN.DPU-16. The IDPU shall provide engineering telemetry sufficient to safely turn-on and operate all instrument as defined in ICDs Compliance. Ref IN.PCB-2: PCB monitors instrument service voltages, currents, temps, and read-backs. (6x8 MUX HS-508 provides 48 inputs) Ref IN.BKP-3: Backplane provides shared analog line from instrument boards to DCB DAC. Ref IN.FSW-16: FSW HSK.A will provide sampling of analog and digital housekeeping, as well as diagnostic higher rates. IN.DPU-17. The IDPU shall provide operational commands and test programs for all instruments as detailed in ICDs Compliance. Ref IN.FSW-17: FSW CMD.A routes commands to individual sensor drivers and to the sensor electronics. FSW will provide uplinked test programs per sensor ICDs (none specified yet). IN.DPU-18. The IDPU shall provide initialization parameters to the Instruments as detailed in the Instrument-IDPU ICDs Compliance. Ref IN.FSW-18: FSW Sensor drivers (EFI/ETC/FGM/SCM) will run command configuration and parameter tables into sensor electronics at initialization. Allocation in EEPROM of up to ~24KB. IDPU-Instrument Accommodation

THEMIS peer PDR Summaries 93 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-19. The IDPU shall provide the on-board FSW processing required and as detailed in the Flight Software Specification Compliance. THM-FSW-002 Flight Software Specification in Review. Ref IN.FSW-19: FSW will provide data processing for EFI & FGM (Spin Fits), and ESA/SST (Spin Sectoring). Moment calculations are no longer a requirement for FSW. IN.DPU-20. The IDPU shall provide Instrument thermal control if necessary Compliance. Ref IN.FSW-20: FSW PWR.A module contains PWM controllers (PID) if needed. Spin Fits: 32 16-bit data points taken at equal angles and stored in array, calculations performed on-board to reduce 32 samples to Offset, Sine and Cosine terms Spin Sectoring: FSW reads Sun Pulse and SRP times, determines Spin Period and SP-SRP, sets 8MHz-Divide-by-N Register to Generate 2^14 Sectors, Changes Divide-by-N to N+1 in Mid-spin. IDPU-FSW Processing

THEMIS peer PDR Summaries 94 October, 2003 REQUIREMENTIDPU DESIGN Time-Based Data Transfer IN.DPU-22. The IDPU shall receive a 2^23 Hz (~8MHz) Master Clock from Probe Compliance. Timing defined in THM-SYS-101 IDPU-to-Probe ICD. IN.DPU-23. The IDPU shall distribute a 2^23 Hz (~8MHz) Clock to DFB and FGM Compliance. Ref IN.BKP-6: Clock to instruments is distributed on backplane. IN.DPU-24. The IDPU shall receive a 1 Pulse Per Second (1PPS) Compliance. Timing defined in THM-SYS-101 IDPU-to-Probe ICD. IN.DPU-25. The IDPU shall provide a 1 Pulse Per Second (1PPS) to DFB and FGM Compliance. Ref IN.BKP-7: 1 PPS synch is distributed on backplane. ICD Figure 4-3: Clock Signal Timing IDPU-Timing and Synchronization

THEMIS peer PDR Summaries 95 October, 2003 REQUIREMENTIDPU DESIGN Spin-Based Data Transfer IN.DPU-26. The IDPU DCB shall receive a raw sun pulse signal from the Probe Compliance. Sun Pulse interface (TBD) is described in THM-SYS-101 IDPU-to-Probe ICD. Ref IN.FSW-22: FSW reads time of received sun pulse from Probe to 16-bits accuracy. FSW polls the hardware registers for SunPulse and SpinRefPulse to 16 usec resolution. IN.DPU-27. The IDPU DCB shall filter the raw sun pulse signal and provide a once-per-spin reference pulse (SRP) to the SST and ESA Compliance. Ref IN.FSW-23: FSW will determine Spin Period to 16 usec and calculates the phase error between SRP and SunPulse. Angles > 1 degree cause a retargeting of SRP to match SunPulse. Angles < 1 degree will be step-filtered. Ref IN.BKP-8: SRP is distributed on backplane. IN.DPU-28. The IDPU DCB shall distribute a Spin Sector Clock with 2^14 phase pulses-per-spin to the ESA and SST (synchronized with the SRP) Compliance. Ref IN.FSW-24: FSW will set divide- by-N register to be N or N+1 at the REM interrupt. Ref IN.BKP-9: Spin Sector Clock is distributed on backplane. IDPU-Timing and Synchronization ICD Figure 4-6: Sun Pulse Interface (TBD) Notes: 1. Provided once per spin 2. Single-ended

THEMIS peer PDR Summaries 96 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-29. Deleted (Redundant)Compliance. N/A IN.DPU-30. The IDPU DCB shall use UTC to time stamp instrument telemetry Compliance. Ref IN.FSW-26: FSW writes UTC into packet headers. IN.DPU-31. The IDPU DCB shall time-tag ESA and SST Spin Reference Pulse (SRP) to <0.5 ms Compliance. Ref IN.FSW-27: FSW provides 16-bit sub-seconds to the packet header (THM-SYS-115c). Derived from 0.1 degree = 0.83 ms for 3 sec spin. IN.DPU-32. The IDPU DCB shall time-tag DFB and FGM data to <2 ms Compliance. Ref IN.FSW-28: FSW calculates time- tags for DFB data. Since data is sync’d to 1 Hz, and each is a binary frequency, FSW need only add a fixed offset per packet. IN.DPU-33. The IDPU DCB subsystem shall obtain time (UTC w/sub seconds) from the Probe Compliance. Ref IN.FSW-29: FSW receives “UTC at the next 1 Hz Tick” in the Probe-to-IDPU packet. FSW decodes at 500ms and latches it at 0ms. FSW will increment “next sec” in case message is missed. IN.DPU-34. The IDPU DCB shall coordinate ESA and SST synchronization by sending spin count to these systems. Compliance. Ref IN.FSW-30: FSW ACS counts SRP pulses and ETC module sends Spin Count to the ETC Actel using the CDI communication IN.DPU-35. The relative sampling times of FGM, SCM and EFI channels shall be fixed and well known for all modes of operation Compliance. IDPU-Timing and Synchronization

THEMIS peer PDR Summaries 97 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-41. The IDPU LVPS/Probe interface voltage shall be 28+/-6V DC Compliance. Ref IN.LVPS-1: LVPS is designed for 22-34 Volts. IN.DPU-42. The IDPU shall use a separate 28+/-6V (lock-out) actuator supply from the Probe Compliance. Ref IN.PCB-6: PCB receives actuator supply and switches service for actuators. IN.DPU-43. The IDPU shall not be damaged by undervoltage conditions Compliance. Will be verified by Test. IN.DPU-44. The IDPU shall provide Instrument regulated, switched and current-limited voltages as detailed in ICDs Compliance. Ref IN.LVPS-5: LVPS provides 1% regulation on directly regulated voltages and 5% on auxiliary. Ref IN.LVPS-8: 2.5 supercession for DCB and PCB Actels is provided by LVPS circuit. Ref IN.PCB-1: PCB provides all power switching to instruments, core systems not switched (DCB and PCB). Current limited switches isolate instruments from core systems. 39 switched services are required. High Rel TO39 quad N & P FETs used. IN.DPU-45. The IDPU shall be capable of providing the transient power needs as detailed in ICDs Compliance. THM-SYS-009 provides peak characteristics of actuators. LVPS services sized for peak power. PCB FETs sized for peak power. IN.DPU-47. Deleted (EFI switching frequency requirement not needed) Compliance. N/A IN.DPU-48. The switching frequencies of all power converters shall be known and analyzed for possible interference with SCM/FGM Compliance. Ref IN.LVPS-4: Frequencies will be 100 kHz or greater. IDPU-LVPS/PCB

THEMIS peer PDR Summaries 98 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-46. The IDPU power line characteristics (i.e. transients, in-rush, ripple, stability, etc) shall be as agreed upon and documented in the Probe-to-IDPU ICD Compliance. Power characteristics defined in IDPU/ESA-to-Probe ICD. Verification Matrices to be completed. Ref IN.LVPS-2: Primaries are current limited. Ref IN.LVPS-4: Supplies are soft started to minimize turn-on stresses, input current controlled Probe +28V Service Characteristics Ripple: function of frequency, defined in ICD figure Transients: less than +/- 2 Volts for 1 msec on supply lines Current Limits: Act like circuit breakers, require ground-commanded reset and including an override capability, shall not trip on transients less than 100ms in duration, negative currents, or by the in-rush current specified Impedance: < 500 milliohms DC-10KHz effective line impedance in the service at the instrument connector IDPU +28V Load Characteristics Grounding: 28V service load shall return its current through the provided return line. The 28V return shall be isolated from signal and chassis ground by at least 1 Mohm and no more than 1  F. Inrush and Transients: <10A for 1 msec; < Peak power consumption after 10ms Current Ripple: Current ripple defined in ICD figure Actuator +28V Load Characteristics Inrush and Transients: <10A for 1 msec; < Peak power consumption after 10ms IDPU-Probe Power Interface From IDPU-to-Probe ICD:

THEMIS peer PDR Summaries 99 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-13. The IDPU shall provide separate enable and activation commands for critical instrument functions such as boom deployments Compliance. Ref IN.PCB-4: PCB provides HV enable switch, ESA provides HV select switches. Ref IN.FSW-13: FSW will only release mag booms, AXB booms and run SPB motors in engineering mode and Armed. Ref IN.EPS-3: Probe provides separate 28V for boom actuator power. Adherence to requirements provides total 3 interlocks. IN.DPU-49. The IDPU shall include sufficient hardware and software safety latches to prevent accidental high voltage turn on to the ESA and SST Compliance. Ref IN.FSW-31: FSW includes 16 Arming bits, 2 for ESA HV and SST. Also, see IN.DPU-13. IN.DPU-50. The IDPU shall include sufficient hardware and software safety latches to prevent accidental deployment of the booms Compliance. Ref IN.FSW-32: FSW includes 16 Arming bits, 1 for Boom Deployments. Also, see IN.DPU-13. IDPU-Safety IDPU Safety Requirement flow-down from programmatic requirements: P-18, P-19, P-20: The THEMIS project shall meet the safety requirements of EWR 127-1, LV, and KHB 1710.3 M-64: If a failure may lead to a catastrophic hazard, the system shall have three inhibits (dual fault tolerant). M-65: If a failure may lead to a critical hazard, the system shall have two inhibits (single fault tolerant). M-66: If a failure may lead to a marginal hazard, the system shall have a single inhibit (no fault tolerant). M-67: Probabilities of hazard occurrence shall be taken into consideration when determining required inhibits. M-68: Systems shall be able to be brought to a safe state with the loss of an inhibit. M-69: All inhibits shall be independent and verifiable. M-70: Design inhibits shall consist of electrical and mechanical hardware. M-71: Operator controls shall not be considered a design inhibit.

THEMIS peer PDR Summaries 100 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-51a. The IDPU box shall accommodate at least five 6U VME cards Compliance. Mechanical design accomodates the following 6 cards: SST Electronics, DFB, BEB, ESA/SST Interface (ETC)/DCB, FGM Electronics (FGE)/PCB, LVPS IN.DPU-51b. The IDPU box shall provide as much radiation protection as possible within mass constraints. Compliance. Preliminary THEMIS Radiation Effects Analysis completed. According to the raytraces, probe provides worst case shielding in the +Z of only 0.34mm. On-going trade: box thickness vs. spot shielding. IDPU-Mechanical ICD Drawing:

THEMIS peer PDR Summaries 101 October, 2003 REQUIREMENTIDPU DESIGN IN.DPU-52. The IDPU box shall be designed in conjunction with board level thermal analysis (part dissipation, heat-sinking, thermal wedge-locks) Compliance. Mechanical design incorporates thermal wedge-locks and heat sinking. IDPU-Mechanical HEAT SINKS WEDGE LOC

THEMIS peer PDR Summaries 102 October, 2003 Ground Based Observatories (GBO) Engineering Peer Review Oct. 17, 2003

THEMIS peer PDR Summaries 103 October, 2003 GBO-Agenda Space Sciences Laboratory Addition Conference Room University of California, Berkeley

THEMIS peer PDR Summaries 104 October, 2003 GBO Derived Requirements

THEMIS peer PDR Summaries 105 October, 2003 GBO-Results from Peer Review Comments from reviewers were positive: “review was conducted with quality information” “details of the system were well engineered” “detailed consideration of environmental accommodation” “Success is likely given the proposers’ excellent experience and track record.” “likely to accomplish not only the THEMIS mission, but also provide a wealth of data for auroral research in general.” “applaud the team for their emphasis on a web based real time delivery of…data” “Overall plan and direction seems good.” “Early deployment, beginning this coming winter, is good idea” Reviewers also provided several recommendations…

THEMIS peer PDR Summaries 106 October, 2003 GBO-Peer Review Action Status, 1

THEMIS peer PDR Summaries 107 October, 2003 GBO-Peer Review Action Status, 2

THEMIS peer PDR Summaries 1 October, 2003 MPDR RFA#4 TITLE: Provide Design Information from the Instrument Peer Reviews REQUESTED BY: Joseph Bolek, Mark.

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THEMIS peer PDR Summaries 1 October, 2003 MPDR RFA#4 TITLE: Provide Design Information from the Instrument Peer Reviews REQUESTED BY: Joseph Bolek, Mark.

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Presentation on theme: "THEMIS peer PDR Summaries 1 October, 2003 MPDR RFA#4 TITLE: Provide Design Information from the Instrument Peer Reviews REQUESTED BY: Joseph Bolek, Mark."— Presentation transcript:

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