1. THEMIS Mission CDR -UCB, June 14-18, 2004 Search Coil Magnetometer (SCM) MCDR Alain Roux, CETP-Velizy Co-i: O.Le Contel Technical Manager: B.de la Porte* =>C.Coillot Lead Engineer: A.Bouabdellah Technicians: D.Alison & S.Ruocco *Till june 2004

2. THEMIS Mission CDR -UCB, June 14-18, 2004 Technical Manager: Bertrand de la Porte team management, general schedule Lead engineer: Christophe Coillot SCM support: design, manufacturing: Sensors : design, manufacturing, tests, PA: electrical design, tests procedures, EM&FM tests. Sniffer design, manufact. & tests Engineer: Abdel Bouabdellah ICD&PAIP management, Vibration tests, PA: PCB cabling, design of housing, manufacturing, PA I/F. Technician: Dominique Alison PA/PCB design, Manufacturing sensors, I/F PA: design, manufact., tests Technician: Sébastien Ruocco Sniffer & tests: Technical Manager: Christophe Coillot team management, schedule. SCM support: manufacturing, schedule, Sensors : manufacturing, EM&FM tests, PA: tests procedures, EM&FM AIT Lead Engineer: Abdel Bouabdellah ICD&PAIP management, Vibration tests, PA: PCB cabling, manufacturing, PA I/F general schedule. Integrations. Technician: Dominique Alison PA/PCB design, Manufacturing sensors, EM&FM tests&integrations Technician: Sébastien Ruocco PA: FM tests. Sensors: FM tests. Integrations Team re-organisation

3. THEMIS Mission CDR -UCB, June 14-18, 2004 IN.SCM-1. SCM shall provide a critical test for the role of waves at substorm onset, in various models (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. 0.7pT/sqHz@10Hz 0.04 pT/sqHz@1kHz IN.SCM-5. The transfer function of the SCM sensors (amplitude &phase) shall be known with an accuracy better than 5%. Compliance. Tests of EM will be made in Chambon la Forêt, end of June. IN.SCM-6. On each spacecraft the 3 magnetic antennas, shall be held orthogonal by a structure procured by CETP Compliance. Structure meets specs : mass, vibrations (modeling, and vibration tests) Sensor requirements

4. THEMIS Mission CDR -UCB, June 14-18, 2004 Sensibility EM (pT/sqrt(Hz) 0.001 0.01 0.1 1 10 1 100100010000 Fréquency (Hz)

5. THEMIS Mission CDR -UCB, June 14-18, 2004 Design includes EPR remarks and numerical simulation results. Interface is completely defined (cf. P. Turin). EM structure delivered by GdTech to CETP: May 17th. 3-axis structure

6. THEMIS Mission CDR -UCB, June 14-18, 2004 PA Design by 3D+ Mechanical characteristics: 2 amplification levels 3 radiation shielding levels Dimensions: 20 x 20 x 15 (mm) Weight : 15 g Pre-Amplifier module

7. THEMIS Mission CDR -UCB, June 14-18, 2004 PA Layout on PCB&box a

8. THEMIS Mission CDR -UCB, June 14-18, 2004 ItemSpecificationStatus Search Coil Size Search Coil Mass 175x175x175 mm 600 g 176x176x176 mm 608 g (+/-8) Most masses meas. Pre-Amp Size Pre-Amp Mass Pre-Amp Power 80x70x40 mm 200 g 90 mW 109 x 94.9 x 30mm 200 g (measured) 86 mW (measured with EM) Power &mass summary

9. THEMIS Mission CDR -UCB, June 14-18, 2004 Operations When ON, SCM is continuously measuring the magnetic field up to 4 kHz. Once per orbit a calibration is run for 30 secs (default) After 60 seconds, the Calibration is automatically turned off.

10. THEMIS Mission CDR -UCB, June 14-18, 2004 Test Matrix Model I/F EM FM Item PA SC PASC+PA SC PASC+PA Electric. Verificat.XXXXXXX Full Calibration XX Mech. I/F,M, CoG, MoIXXXX VibrationsQQAA Thermal tests (cycles)QQAA Thermal Vacuum Q.idpuA.idpu Interface to IDPUX Pre-integration UCBXXXX Integration to S/CXX

11. THEMIS Mission CDR -UCB, June 14-18, 2004 Test plans : SC After winding of internal tube Verification of Impedance Done (EM) After potting of the magnetic core Verif. of imped. Magnetic flux resp. (with PA Done (EM) After overall pottingVerif. of imped. Magnetic flux resp. (with PA To be done end of june EM After 3-axis assembly, and connect. to PA Transf. funct. (SC in mu- metal box, metrology, vibr., temp. limit, Full cal. in Chambon Begin of july EM After delivery to UCBTherm. Vac (with S/C)

12. THEMIS Mission CDR -UCB, June 14-18, 2004 Test plans: PA cubes Single flexElectrical verification Offset adjustment Done (EM&FM) Done(EM) After cube assembly &potting Electrical verification Temperature test* (-50° - +60°) Done(EM &FM) Done(EM) * Takes into account changes suggested during CDR peer review

13. THEMIS Mission CDR -UCB, June 14-18, 2004 Test plans: full PA box After PCB cablingElectrical verificationDone EM After assembly in the housing Electrical verification Metrology Vibrations Full range temp. tests Done TB done Done Connect. with SCTransfer funct.,SC in mu- metal box. Full cal. in Chambon End of June After delivery to UCBThermal vac. With IDPU

14. THEMIS Mission CDR -UCB, June 14-18, 2004 Bench test configuration

15. THEMIS Mission CDR -UCB, June 14-18, 2004 Mag. calibration: Chambon

16. THEMIS Mission CDR -UCB, June 14-18, 2004 Interface verification at UCB An interface model has been built and sent to UCB to test I/F to IDPU. Same Power, Command, analog output interfaces Power and Cal Mode identification by LED Cal Signal re-injected to the input A signal generator can be connected to each input

17. THEMIS Mission CDR -UCB, June 14-18, 2004 Pre-integrations at UCB After delivery to UCB (Incoming Inspection, Bench Test) Sensor in the mu-metal box Electrical Integration Power ON and functionnal test Validation can only be done by analysis of telemetry data I&T at UCB

18. THEMIS Mission CDR -UCB, June 14-18, 2004 I&T at s/c level Integration on the spacecraft Mechanical Integration of the PA, connection to the boom harness Sensor in the mu-metal box Electrical Integration (bounding, isolation) Power ON and functionnal test Validation can only be done by analysis of telemetry data

19. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM tests at s/c level: 1 Initial configuration: The sensor is inside the mu- metal box, connected to the PA via the boom harness Requirement: keep the sensor in the mu-metal box until all experiments are integrated in the spacecraft (mission operation test)

20. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM tests at s/c level: 2 WHAT CAN BE DONE WITH THE SENSOR IN THE MU- METAL BOX? Verification of the labelling of axis (X,Y, Z) (Re)-verification of the end-to-end calibration Phase relation between the 3 components (for the waveforms) Measure the conducted noise SCM/EField timing reference [and inter-calibration]

21. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM integr. at s/c level: 3 SENSOR MOUNTED ON THE BOOM PA saturated by the 50/60 Hz (except in an EMC chamber). No measurement possible but a major failure would be detectable. INSTALLATION OF THE MLI: preferably at the last moment, before s/c vibration tests.

22. THEMIS Mission CDR -UCB, June 14-18, 2004 EMC tests at s/c level CETP can help analyse the AC radiated noise around the spacecraft. A « magnetic sniffer » has been built and delivered to UCB. In order to avoid the saturation by the 50/60 Hz, the analysis is separated into two bandwidths: below 50 Hz and above 300 Hz (5th harmonic).

23. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM integr.; team support The SCM team will support all critical activities, for the integrations. However, due to the large number of satellites, a strategy should be implemented to limit the number of travels, cost and time spent Support EM integrations in any case The FM will be delivered 3 by 3 and the level of support for each test will be agreed upon with UCB Capability of remote access/support should be implemented

24. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM schedule- Key dates EM delivery to UCBJuly 2004 EM pre-integrations at UCB July 2004 3D cubes (FM) delivery to CETP July 23th, 2004 FM1,2, and 3 availability:Sept. 24 th, 2004 FM4,5, and 6 availability:Nov.10 th, 2004

25. THEMIS Mission CDR -UCB, June 14-18, 2004 Status of questions/RFA’s SCM-1 Ground ing & testing Concern that grounding and shielding is not yet defined—need to make sure all documents are consistent. This was an action from the last review, but understand that this is common for CDR-level fields missions. Grounding review (end of may) UCB&CETP agreed upon: Coils&shields of each SCA  GND (not to CGND) Thermal blanket  CGND Overall shielding of boom cable by conductive tape. Backshell of PA connector also shielded No need to shield SCA connect. SCM-2 Simult. Firing of actuat. Ensure that both actuators are fired simultaneously, at temperature and voltage extremes during testing. (Slavin—based on Double Star dual boom deployment failure.) The mag-booms are released simultaneously

26. THEMIS Mission CDR -UCB, June 14-18, 2004 Status of questions/RFA’s SCM-3 Tests of 3D components beyond predicted levels CETP should ask 3D to test components beyond the predict levels. Most electronic parts are tested at greater levels individually than at assembly level. Done; new test procedures defined with UCB&3D; temperatures ranges extended by +/-5° SCM-4 PCB mounted on 4 corners PCB mounted on four corners. Is this adequate for limit loads for deflection [probably okay, ~4mm standoffs] and strength? Recommend calculation to ensure populated board does not exceed strength limits. It is not typical to calculate the strength requirement of boards. Vibration test performed successfully. SCM-5 Wires inside PA box Wires from connectors to board are long. The wires should be laid out differently (increase board size, glue the longest wire on the PCB?) Longest wires are now glued

27. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM-6 details SCM-6 (cnd.) Summary of THM-SYS-005: SC(antennas) qualified by CETP (thermal cycling) without vacuum. TV test at s/c level. PA qualified in temperature (currently done) by CETP, without vac.. TV done at UCB, together with IDPU.

28. THEMIS Mission CDR -UCB, June 14-18, 2004 Status of questions/RFA’s SCM-6 Thermal vac./thermal air cycling UCB and CETP need to have an agreement on how many thermal vacuum or thermal air tests cycles are performed before delivery (by s/c CDR) THM-SYS-005 calls out the required cycles & temperatures SCM-7 Thermal levels Thermal levels should come from document such as environmental requirements. We are adding a reference to "THM-SYS-005 Instrument Payload Verification Plan and Environmental Test Specification" to the ICD SCM-8 Test sequencing Details of test sequencing, configuration (are sensors connected to pre-amps during testing)-Teams have begun to discuss; more meetings between the I&T lead, PM, SE and CETP would be beneficial. Marc Kaylor (Swales) is drafting the basic probe flow, so that Rick Sterling can insert the details of the SCM tests.

29. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM-9 Review EMI/EMC levels relative to FAST Rick Schnurr volunteers to review EMI/EMC levels relative to FAST, and tell UCB which levels may present difficulties (noise in the chamber). Data has been provided to Rick. SCM-10 Populating boards in advance Recommend populating boards in advance of 3D cube arrival, to help schedule Agreed SCM-11 Nickel plating of small objects far away from sensor Would be beneficial in magnetics plan to note: don’t consider nickel plating small objects far away from sensor (such as nickel coating on 3D cubes). Although not specifically called out in the magnetics plan, the use of nickel plating has been tested and tracked. The SCM Pre-Amp 3D Plus modules were tested in Braunshweig in Dec. and determined to have a magnetic moment well within the requirements for THEMIS. Status of questions/RFA’s

30. THEMIS Mission CDR -UCB, June 14-18, 2004 SCM-12 Thermal treatments on e-box. Thermal treatments on e-box is in need of definition. The thermal treatments have now been defined by UCB. The top of the preamp will be anodized but the rest of the box can remain alodine. SCM-13 Chambers used for EMI/EMC tests The chambers used for EMI/EMC tests usually do not present a clean AC magnetic environment. This is why tests on subsystem with a search coil inside a large mu-metal chamber are important when a careful verification is needed. Such a facility exists in France at Chambon-la-Foret. We believe this is a recommendation to do what we have planned. So the response is to keep going as planned. Status of questions/RFA’s

31. THEMIS Mission CDR -UCB, June 14-18, 2004 Ressources (mass & power) are compatible with allocation. Tight schedule, yet delivery dates for EM and FM are compatible with the schedule of the project. PA cubes (EM) meet requested performances. PA box passed temp. & vibr.tests ; no problem. Sensitivity meets specs Antenna structure (EM) delivered. Meets specs. Summary