THEMIS IDPU FSW V 4 Introduction Part IV

THEMIS IDPU FSW V 4 Introduction Part IV Triggers June 20, 2006 THEMIS IDPU FSW 12/22/2021 1 UCB

Agenda Part IV Triggers 1. 2. 3. 4. 5. REQUIREMENTS SPECIFICATIONS ORBIT EVENTS FUNCTIONAL DEFINITIONS FUNCTIONS 1. 2. 3. 4. 5. 6. 7. 6. ION VELOCITY E-FIELD B-FIELD AKR FILTERS ION DENSITY PRESSURE DEVELOPMENT PLAN THEMIS IDPU FSW 12/22/2021 2 UCB

Requirements Basics 1. 2. 3. 4. 5. 6. 7. Capable of Running on 8085 concurrent with Spin Fits, High Speed Telemetry RAW Data input from Sensors in Real Time Produce Results Fast Enough to be Useful (< 1 spin) Calculation Should Produce 8 -bit 0 -255 value for Burst Evaluation Calculations Should Not Always Produce Max (255) or Min (000) Calculations Should not Trigger on Junk Events (e. g. eclipse entry, etc) Trigger Packet will provide data on ALL trigger functions useful in commissioning period Test Requirements 1. 2. 3. 4. 5. 6. Test on the Instruments on the Ground, Only Verify in Orbit Computer simulations do not have required fidelity Maintain a Functional Instrument (Spare) or ETU on ground for testing modifications Use the Spare Probe for Verifying triggers in orbit Coordination of trigger modifications will have to be improved New trigger development and test will take several weeks depending upon complexity. THEMIS IDPU FSW 12/22/2021 3 UCB

Specification Recent Activities 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. Historically, THM_FSW_003_CTM contained the Filter Formulae FSW Versions thru 4. 0 were built to this specification New Formulae were suggested for E-Field, B-Field and ESA triggers FSW Version 4. 00 e was developed and tested in May THM_FSW_223_SCI described the implementation of these triggers (5/27) Email traffic suggested the triggers needed redefinition Drop-dead date of 5/31/06 established but missed. Tech Memo 6/2/06 (Bonnell) to nail down the discussions MSE (Taylor) request to team to sign the 6/2/06 Tech Memo. No response Emergency meeting on Triggers 6/14/06 produced updated Tech Memo and a new request to sign it. No response. Continued Email traffic on Scale Factors and formulae This meeting on Triggers 6/20/06. Status & Recommendation 1. 2. 3. 4. Flight Software V 4. 01 is ready except for Triggers We Should Have Functionality in V 4. 01 that is not in V 4. 00 (currently in Probes) Without a signed specification today, FSW V 4. 01 will include no triggers It is not clear if a V 4. 02 is practical before launch. THEMIS IDPU FSW 12/22/2021 4 UCB

P 2 ORBIT EVENTS TAIL SEASON w/ ECLIPSE 42: 30: PASS END /IDPURAWHEX 1004 ; DISABLE BURST XMIT /ITMENABLE 0 ; STOP FIFO ACTIVITY 42: 00: PASS START /IDPURAWHEX 1084 ; ENABLE BURST XMIT /ITMENABLE F ; PLAY ALL SEGMENTS WAIT 1 /ITMPLAY ; ENGAGE 47: 00 MAG CAL ON 30: 00: SLOW SURVEY MODE /IDPURAWHEX 1005 ; TRIGGER DISABLE /IDPURAWHEX 1003 ; WBURST DISABLE /IDPURAWHEX 1002 ; PBURST DISABLE /IDPURAWHEX 1001 ; SLOW SURVEY /IDPURAWHEX B 80 F ; COMPRESS ALL 25: 00: ECLIPSE EXIT /ISCRIPTEXEC 91 34: 00: 100% COMPRESSED 00: 00 01: 00 MAG CAL OFF 23: 00: ECLIPSE ENTRY /ISCRIPTEXEC 90 18: 00: FAST SURVEY, BURSTING MODE /IDPURAWHEX 1081 ; FAST SURVEY MODE /IDPURAWHEX 1082 ; PBURST ENABLE /IDPURAWHEX 1083 ; WBURST ENABLE /IDPURAWHEX 1085 ; TRIGGER ENABLE Orbit Period : 48 hours Fast Survey : 12 hours Compression: 4 hours THEMIS IDPU FSW 12/22/2021 5 UCB

DEFINITIONS POS(x) = x, if x>0, and 0 if x<=0. This is used to implement an "onset" filter that has high value when things are increasing, but minimal value when they are decreasing. IIR 4() filter is defined as follows: Fn = (3*Fn-1 + Xn ) / 4. LIMIT 12() is used for values to be filtered. If a filter-input value is larger than 12 bits, it is limited to 12 bits. This protects the filter from taking on large values it cannot reasonably recover from. All formulae should target 12 -bit results internally. The filter will carry 12 -bits and the ultimate trigger value will be the upper 8 bits of the 12 -bit value. This allows the filter to finally settle on the input value. SCALE is TBD scale factor to bring relevant range of trigger qty into 8 -bit range; TBR values for SCALE are included if they are currently known. All the SCALE factors for a given set of trigger functions would live in a table of some sort (SCI table? ). THEMIS IDPU FSW 12/22/2021 6 UCB

ION VELOCITY Function: VXY Purpose: PB trigger. Region/Probe/Rationale: Tail/P 1, P 2/Boundary Layer Tail/P 3, 4, 5/Tail/Current disruption Data Source: Moments packet. Calculation Period: 1/Spin Algorithm: q = LIMIT 12[ SCALE_VXY*sqrt( NVX_IESA 2 + NVY_IESA 2)/N_IESA ] VXY = POS( q - IIR 4(q)) /16 Note 1: SCALE_VXY is a FLOAT value such that q is 12 -bit. Note 2: If N_IESA is zero, the calculation is not attempted and VXY is not updated. THEMIS IDPU FSW 12/22/2021 7 UCB

E-FIELD Function: EY Purpose: PB trigger. Region/Probe/Rationale: Tail/P 3, 4, 5/Convective flows Data Source: Spin Fit E-Field. Calculation Period: 1/Spin Algorithm: q = LIMIT 12 [ C_E * 2 SCALE_EY] EY = POS( q - IIR 4( q)) /16 Note 1 : C_E is sin() coefficient from E-field spin fit, and has a range of [-1, +1], corresponding to the +/- 300 m. V/m range of the EDC channels. Note 2 : The objective is to have a 10 m. V/m jump correspond to ~ 100 for EY. Note 3 : The default 2 SCALE_EY is 65536. THEMIS IDPU FSW 12/22/2021 8 UCB

B-FIELD Function: BZ Purpose: PB trigger. Region/Probe/Rationale: Tail/P 3, 4, 5/Dipolarization, noise; Dayside/all/Noise in Cavities, HFAs Data Source: Spin Averaged B-field. Calculation Period: 1/Spin Algorithm: q = LIMIT 12[ SCALE_BZ*ABS(Spin. Average(FGMx)) / 2 RANGEX ] BZ = ABS( q - IIR 4(q)) /16 Note 1: FGMx is the spin axis magnetic input, a 16 -bit value. Note 2 : The objective is to have a 20 n. T jump correspond to ~100 for Bz Note 3: SCALE_BZ is an 8 -bit unsigned value (default 8) Note 4: RANGEX is a 4 -bit code used to amplify the signal into the Spin Fitter. It is used here to correct for gain changes in the range. THEMIS IDPU FSW 12/22/2021 9 UCB

AKR Function: AKR Purpose: PB trigger. Region/Probe/Rationale: Tail/all/Auroral onset Data Source: APID 451, HFavg field. Calculation Period: 1/Sec Algorithm: q = LIMIT 12[ SCALE_AKR*Hfavg ] AKR = POS( q - IIR 4( q)) /16 Note 1: SCALE_AKR is 8 -bit unsigned value (Default 16); Note 2: 12 -bit limit applied to the 8 x 8 bit calculation THEMIS IDPU FSW 12/22/2021 10 UCB

FILTERS Function: FB Purpose: WB trigger. Region/Probe/Rationale: Tail/all/substorm waves; Radbelt/all/storm waves; Dayside/all/mpause, shock, upstream waves Data Source: IFILTER 1, IFILTER 2 (from DFB). Calculation Period: 1/Sec Algorithm: q = LIMIT 12[ SCALE_FB 1*IFILTER 1 + SCALE_FB 2*IFILTER 2 ] FB = POS( q - IIR 4( q)) /16 Note 1: SCALE_FB 1 and SCALE_FB 2 used to bring units and relative amplitudes of the two selected filter bank channels onto an equal (or unequal) footing; both are 8 -bit unsigned values (Default 8); Note 2: 12 -bit limit applied to the sum of 2 8 x 8 bit calculations Note that IFILTER 1 and IFILTER 2 can be set to point to any of the elements of the Filter. Bank data; ie. both in FB 1; one in FB 1 and one in FB 2; both in FB 2. This freedom can be exploited to make a trigger function that is sensitive to two different sorts of wave phenomena in the Efield or B-field data, for example. THEMIS IDPU FSW 12/22/2021 11 UCB

ION DENSITY Function: NI Purpose: PB trigger. Region/Probe/Rationale: Dayside/all/HFAs and cavities Data Source: Moments packet. Calculation Period: 1/Spin Algorithm: q = LIMIT 12[ SCALE_NI*N_IESA ] NI = abs( q - IIR 4( q)) /16 Note 1 : SCALE_NI is a FLOAT used to reduce N_IESA to 12 -bits Note 2: 12 -bit limit applied to the integer value q. THEMIS IDPU FSW 12/22/2021 12 UCB

PRESSURE Function: SST_PRES Purpose: PB trigger (WB trigger for Rad. Belt science). Region/Probe/Rationale: Tail/P 1, 2/Boundary Layer Beams; Radbelts/all/Substorm injection, particle acceleration; Dayside/P 1/Upstream events Data Source: Moments packet. Calculation Period: 1/Spin Algorithm: q 1 = SCALE_SSTF 1[ log 2( MXX_ISST ) + log 2(SST_ATTEN) ] q 2 = SCALE_SSTF 2[ log 2( MXX_ESST) + log 2(SST_ATTEN) ] SST_FLUX = POS(q 1 -IIR 4(q 1)) + POS(q 2 -IIR 4(q 2)) Note 1: log 2(SST_ATTEN) = correction factors for SST OPEN = 0, CLOSED=7; Note 2: SCALE_SSTF 1 and SCALE_SSTF 2 used to put electon and ion fluxes on equal (or unequal) footing. Note 3: When attenuator state switches, filters will be reset to the current value. This will make SST_FLUX zero in that spin, but keep the system from having a glitch. Note 4: Expected input values for Mxx_ISST and ESST are 32 -bit positive values. THEMIS IDPU FSW 12/22/2021 13 UCB

PLAN Problem: Dwindling Development Capabilities 1. 2. 3. 4. 5. Flight Instruments all on Probes Probe Environmental Tests Require Team at JPL Probe GSE Does Not Support Trigger Input Signals SST/ESA Reformatting (Revision 5) Needs to be Tested Formulae are Complex Enough – Could Cause On-Orbit Resets in Limiting Cases Work to be Done 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. ETC Rev 5 Integration and Test on ETU Update CTM to Include New Packet Lengths to support Rev 5 Update Change Requests to Record SCR-52 Generate Test Sets for the New Functions in TEST_SCR 52 New Packet Lengths and Displays on the GSE to support Rev 5 FSW Trigger Module Numeric Properties and Performance Estimates FSW Trigger Module Integration and Test on ETU with Simulated Data FSW Version 4. 01 Regression Test on ETU FSW Version 4. 01 Orbit Simulations (Long Duration Tests) on ETU FSW Version 4. 01 Installation on Probe 2 • 11. 12. Post PCA Vibration Date is 7/21/06 Instrument CPT on Probe 2 FSW Version 4. 01 Installation on Probes 1, 3, 4, 5 • Post TV Date is 8/11/06 PSR THEMIS IDPU FSW 12/22/2021 14 UCB