Software Interface Specification

1. General Description

1.1 Purpose

The Small Forces File (SFF) provides to JPL's Orbit Determination Program (ODP) and interested science teams the cumulative delta-V effect of attitude thruster firings over one or more specified intervals of time. In some cases it also provides an estimate of the cumulative spacecraft mass loss due to the use of propellant in those attitude thrusters.

The same format file is also produced to model predicted accelerations.

1.2. Scope

This SIS is applicable for the Mars Polar Lander (MPL), Stardust (SDU), Genesis (GNS), Mars Odyssey 2001 Orbiter (M01), Deep Impact Flyby (DIF) and Mars Reconnaissance Orbiter (MRO) spacecraft. It covers both "predict" and "reconstruction" situations. For Stardust predict situations, it covers two kinds of predict Small Forces Files: one containing delta-velocity (typically from spacecraft slews, dead-band walks and other delta-V generating events) and one containing acceleration (typically from cruise limit cycling).

1.3 Applicable Documents

Several programs exist for creating this Small Forces File. See the relevant program User Guides for operating details. These are:

LANDSF Mars Polar Lander predict SFFs

MAKSDP Stardust predict SFFs

SMF_PREDICT Genesis short-term predict SFFs

MAKGNP Genesis long-term predict SFFs

MAKSFF MPL, SDU, GNS, M01, DIF, and MRO reconstruction SFFs

SMALLFORCEMERGE Program for merging predict and reconstruction SFFs

See the relevant Operations Procedures and Operational Interface Agreements for information about production procedures, schedules and file destinations.

2. Method of Generation

2.1 Predict Mode

A Small Forces File may be produced in "predict" mode by a program that models expected delta-V (and acceleration, in the case of Stardust) based on expected performance or knowledge of the spacecraft attitude control system and the mission profile. Separate programs for producing predict Small Forces Files are available for the Mars Polar Lander, Stardust, Genesis and MRO flight projects. See the LANDSF, MAKSDP, MAKGNP, SMF_PREDICT, and ATARPS/ATARPS2SFDF/MAKSFF User's Guides, respectively.

2.2 Reconstruction Mode

A Small Forces File may be produced in "reconstruction" mode by a set of scripts and programs that obtain Small Forces File packets returned from the spacecraft and post-process and/or reformat this data into an SFF. This process includes some computations of derived parameters. See the MAKSFF User's Guide and the relevant Operations Interface Agreements, Operational Procedures and SPAS SRDS documents for production details.

2.3 Merging Predict and Reconstruction Delta-V Files

The file merging information in this subsection does not deal with the format or content of an SFF and so is not a subject appropriate for detailed discussion in this SIS. See the appropriate operational procedure for the mission of interest for the official instructions about merging SFF files.

The ODP can read only one delta-V Small Forces File during execution. Consequently, means external to the ODP are needed to combine "predict" and "reconstruction" delta-V SFF data as needed into a single file.

For all six spacecraft - MPL, SDU, GNS, M01, DIF, and MRO - the merging of reconstruction data with predict data can be accomplished with the SMALLFORCEMERGE program.

The ODP can also read only one accelerations file. Since there is no reconstruction accelerations file, merging of accelerations SFFs is not an issue. Note, however, that the accelerations file must be truncated to start where the delta-V reconstruction file ends; otherwise inconsistent data will be input to the ODP.

3. Detailed Data Object Definition

3.1 General Structure

A small forces file consists of two sections-header and data-separated by an end of header character flag on a line by itself:

$$EOH

<data>

where

<header> is a set of KEYWORD=VALUE assignments

$$EOH is end-of-header delimiter, on a line by itself

<data> is one or more small forces data records

There is no special end of file marker inserted at the end of the data section.

3.2 Header Section Structure

The header section consists of the following KEYWORD=VALUE assignments, each on a line by itself. Any amount of white space, including none, can appear on each side of the "=" sign.

MISSION_NAME = <character string>

SPACECRAFT_NAME = <character string>

DSN_SPACECRAFT_ID = <positive integer>

PRODUCTION_TIME = YYYY-MM-DD HR:MN:SC[.XXX]

PRODUCER_ID = <character string>

where

MISSION_NAME	name of the mission (Stardust, M98, GNS, M01, DI, MRO)
SPACECRAFT_NAME	name of the spacecraft (Sdu, M98, Gns, Or1, Dif, Mro)
DSN_SPACECRAFT_ID	DSN ID for the spacecraft: (Stardust = 29, Mars Polar Lander = 116, Genesis = 47, M01 = 53, DIF = 140, MRO = 74)
PRODUCTION_TIME	file production date and time, taken from the local computer clock
PRODUCER_ID	name/organization of the producer; example: NAIF/JPL

It is noted here that within the Stardust, Mars Surveyor 98, Genesis, Mars Odyssey 2001, Deep Impact, and Mars Reconnaissance Orbiter projects, and particularly their ground systems, several names for the missions and spacecraft are in use. The values for MISSION_NAME and SPACECRAFT_NAME shown in the table above seem not to be the best choices in all cases, but they are the only consistent set of names that can be placed in the SFF header by the SFF production programs. The software for which this SFF product was designed does not use either of these items (it uses only the DSN_SPACECRAFT_ID from the header) so the values (including case) for MISSION_NAME and SPACECRAFT_NAME placed in the header are not important.

3.3 Data Section Structure

The data section of a small forces file consists of one or more data records, each record occupying a single line:

...

Although the records are usually sorted in increasing order by STOPTIM field from the primary portion of the record, this sorting is not guaranteed.

3.3.1 Data Record Structure Overview

Each data record of a small forces file consists of two parts delimited by a comma, the primary data part and additional data part:

The additional data part is optional. If it's not present, the delimiting comma is omitted.

Spaces preceding or following commas are insignificant.

3.3.2 Data Record Primary Data Structure

The primary data part of a small forces data record consists of the following required parameters in the order shown, separated by commas:

INDEX,RECTYPE,GENTIM,STARTTIM,STOPTIM,DTIME,DMASS,DVX,DVY,DVZ

where

INDEX	index of the record in the file (1...N)
RECTYPE	type of the record, one character string: for velocity files: P = predicted, R = reconstructed for predicted acceleration files: A = continuous, X = discontinuous
GENTIM	record generation time; format: YYYY-MM-DD HR:MN:SC[.XXX]; taken from the local computer clock (implies UTC for TMOD computers)
STARTTIM (ET)	data accumulation period start time; format YYYY-MM-DD HR:MN:SC.XXX. For predict delta-V files, this item = STOPTIM and corresponds to the time for application of delta-V for a delta-V generating event event.
STOPTIM (ET)	data accumulation period stop time; format YYYY-MM-DD HR:MN:SC.XXX. For predict delta-V files, this item = STARTTIM and corresponds to the time for application of delta-V for a delta-V generating event event.
DTIME (Seconds)	For reconstruction files, data accumulation period duration (STOPTIM - STARTTIM). For Sdu predict delta-V files, computed from a table of estimated delta-V generating event durations, varying by delta-V generating event type. For MPL predict files, corresponds to the length of the interval ending at STOPTIM that is used to determine the predicted delta-V. For GNS predict files, this is zero.
DMASS or DMASS rate (Kg or kg/sec)	Always zero for MPL, GNS, M01, DIF, and MRO files. For SDU reconstruction velocity files this is computed from estimated mass flow rate (parameter updated after each major maneuver) and thruster on time (kg). For Sdu predicted velocity files, computed from table of estimated mass decrement by delta-V generating event type (kg). For Sdu predicted acceleration files, mass flow rate is computed from specific impulse and predicted ACS acceleration (kg/sec). Positive DMASS value means mass loss.
DVX or AX (m/s or m/s**2)	resultant delta-V in J2000 frame X direction for the accumulation time period; or for Stardust acceleration files, resultant acceleration in X direction
DVY or AY (m/s or m/s**2)	resultant delta-V in J2000 frame Y direction for the accumulation time period; or for Stardust acceleration files, resultant acceleration in Y direction
DVZ or AZ (m/s or m/s**2)	resultant delta-V in J2000 frame Z direction for the accumulation time period; or for Stardust acceleration files, resultant acceleration in Z direction

3.3.3 Data Record Additional Data Structure

The additional data part of a small forces data record consists of the following parameters requested by a particular mission in the order in which they appear in the mission's small forces APID, plus optional SPICE DPSCLK, separated by commas:

AAAA, BBBB, CCCC, ....., ZZZZ, DPSCLK

where

AAAA	a field from a mission small forces APID
BBBB	a field from a mission small forces APID
CCCC	a field from a mission small forces APID
...	...
ZZZZ	a field from a mission small forces APID
DPSCLK	SPICE double precision SCLK (SCLK ticks)

These additional data are not provided in the SFF for Mars Polar Lander but are provided in the SFFs for Stardust, Genesis, M01, DIF, and MRO. See the description below of the fields that will be included. SPICE double precision SCLK must be provided in any reconstruction SFF even if other additional fields aren't present in order use the file with as input to the MAKSFF program (version 3.0.0 or later).

3.3.3.1 Stardust Mission Additional Data

For the Stardust mission the additional data part of a small forces data record consists of the following parameters, occurring in the order in which they appear in the small forces APID. These data items are separated by commas and appear on the same line as, and after, the primary data.

Q1, Q2, Q3, Q4, RCS1N, RCS2N, RCS3N, RCS4N, RCS5N, RCS6N, RCS7N, RCS8N, TCM1N, TCM2N, TCM3N, TCM4N, TCM5N, TCM6N, TCM7N, TCM8N, RCS1T, RCS2T, RCS3T, RCS4T, RCS5T, RCS6T, RCS7T, RCS8T, TCM1T, TCM2T, TCM3T, TCM4T, TCM5T, TCM6T, TCM7T, TCM8T

where

Q1	First element of average attitude quaternion at time of thruster firings
Q2	Second element of average attitude quaternion at time of thruster firings
Q3	Third element of average attitude quaternion at time of thruster firings
Q4	Fourth element of average attitude quaternion at time of thruster firings (scalar component)
RCS1N	Number of firings during time period for RCS1
RCS2N	Number of firings during time period for RCS2
RCS3N	Number of firings during time period for RCS3
RCS4N	Number of firings during time period for RCS4
RCS5N	Number of firings during time period for RCS5
RCS6N	Number of firings during time period for RCS6
RCS7N	Number of firings during time period for RCS7
RCS8N	Number of firings during time period for RCS8
TCM1N	Number of firings during time period for TCM1
TCM2N	Number of firings during time period for TCM2
TCM3N	Number of firings during time period for TCM3
TCM4N	Number of firings during time period for TCM4
TCM5N	Number of firings during time period for TCM5
TCM6N	Number of firings during time period for TCM6
TCM7N	Number of firings during time period for TCM7
TCM8N	Number of firings during time period for TCM8
RCS1T	Accumulated on time during time period for RCS1
RCS2T	Accumulated on time during time period for RCS2
RCS3T	Accumulated on time during time period for RCS3
RCS4T	Accumulated on time during time period for RCS4
RCS5T	Accumulated on time during time period for RCS5
RCS6T	Accumulated on time during time period for RCS6
RCS7T	Accumulated on time during time period for RCS7
RCS8T	Accumulated on time during time period for RCS8
TCM1T	Accumulated on time during time period for TCM1
TCM2T	Accumulated on time during time period for TCM2
TCM3T	Accumulated on time during time period for TCM3
TCM4T	Accumulated on time during time period for TCM4
TCM5T	Accumulated on time during time period for TCM5
TCM6T	Accumulated on time during time period for TCM6
TCM7T	Accumulated on time during time period for TCM7
TCM8T	Accumulated on time during time period for TCM8

3.3.3.2 Genesis Mission Additional Data

For the Genesis mission the additional data part of a small forces data record consists of the following parameters, occurring in the order in which they appear in the output of the SMF_RECON program. These data items are separated by commas and appear on the same line as, and after, the primary data.

SPACECRAFT_MASS, SPACECRAFT_INERTIA, ACS_MODE, TLM_SRC_BCKSHELL, USED_SRC_BCKSHELL, TLM_CANN_COVER, USED_CANN_COVER, TLM_B_ARRAY_POS, USED_B_ARRAY_POS, TLM_E_ARRAY_POS, USED_E_ARRAY_POS, TLM_H_ARRAY_POS, USED_H_ARRAY_POS, TLM_L_ARRAY_POS, USED_L_ARRAY_POS, PRE_H_X_COMP, PRE_H_Y_COMP, PRE_H_Z_COMP, PRE_OMEGA, POST_H_X_COMP, POST_H_Y_COMP, POST_H_Z_COMP, POST_OMEGA, START_SEQ_COUNT, STOP_SEQ_COUNT, SRC_SEQ_FLAG

where

SPACECRAFT_MASS	The mass of the spacecraft in kilograms.
SPACECRAFT_INERTIA	The inertia of the spacecraft in (kilograms * meters^2).
ACS_MODE	One of the ACS mode strings.
TLM_SRC_BCKSHELL	May be OPEN, CLOSED or UNKNOWN. The string is the position of the sample return canister back shell as read from the telemetry.
USED_SRC_BCKSHELL	May be OPEN, CLOSED or UNKNOWN. The string is the position of the sample return canister back shell as read from the mass properties file.
TLM_CANN_COVER	May be OPEN, CLOSED or UNKNOWN. The string is the position of the canister cover as read from the telemetry.
USED_CANN_COVER	May be OPEN, CLOSED or UNKNOWN. The string is the position of the canister cover as read from the mass properties file.
TLM_B_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the B array as read from the telemetry.
USED_B_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the B array as read from the mass properties file.
TLM_E_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the E array as read from the telemetry.
USED_E_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the E array as read from the mass properties file.
TLM_H_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the H array as read from the telemetry.
USED_H_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the H array as read from the mass properties file.
TLM_L_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the L array as read from the telemetry.
USED_L_ARRAY_POSITION	May be STOWED, DEPLOYED, UNSHADED or UNKNOWN. The string is the position of the L array as read from the mass properties file.
PRE_H_X_COMP	The X component of the angular momentum direction vector (unit vector) before the maneuver segment. The vector is in the EME2000 reference frame.
PRE_H_Y_COMP	The Y component of the angular momentum direction vector (unit vector) before the maneuver segment. The vector is in the EME2000 reference frame.
PRE_H_Z_COMP	The Z component of the angular momentum direction vector (unit vector) before the maneuver segment. The vector is in EME2000 reference frame.
PRE_OMEGA	The spin rate before the maneuver segment in radians/second.
POST_H_X_COMP	The X component of the angular momentum direction vector (unit vector) after the maneuver segment. The vector is in the EME2000 reference frame.
POST_H_Y_COMP	The Y component of the angular momentum direction vector (unit vector) after the maneuver segment. The vector is in the EME2000 reference frame.
POST_H_Z_COMP	The Z component of the angular momentum direction vector (unit vector) after the maneuver segment. The vector is in the EME2000 reference frame.
POST_OMEGA	The spin rate after the maneuver segment in radians/second.
START_SEQ_COUNT	The SRC_SEQ_COUNT of the first packet associated with this record.
STOP_SEQ_COUNT	The SRC_SEQ_COUNT of the next header packet associated with this record.
SRC_SEQ_FLAG	May be TRUE or FALSE. False, indicates that a problem has been detected with the SRC_SEQ_COUNT either for this record or for a packet between this record and the previous record. TRUE, indicates no problem has been detected.

3.3.3.3 Mars Odyssey 2001 Mission Additional Data

For the M01 mission the additional data part of a small forces data record consists of the following parameters, occurring in the order in which they appear in the small forces APID. These data items are separated by commas and appear on the same line as, and after, the primary data.

AVG_ATT_QUAT_Q1, AVG_ATT_QUAT_Q2, AVG_ATT_QUAT_Q3, AVG_ATT_QUAT_Q4, RCS1_ACC_ON_CMDS, RCS2_ACC_ON_CMDS, RCS3_ACC_ON_CMDS, RCS4_ACC_ON_CMDS, TCM1_ACC_ON_CMDS, TCM2_ACC_ON_CMDS, TCM3_ACC_ON_CMDS, TCM4_ACC_ON_CMDS, ME1_ACC_ON_CMDS, ME2_ACC_ON_CMDS, RCS1_ACC_ON_TIME, RCS2_ACC_ON_TIME, RCS3_ACC_ON_TIME, RCS4_ACC_ON_TIME, TCM1_ACC_ON_TIME, TCM2_ACC_ON_TIME, TCM3_ACC_ON_TIME, TCM4_ACC_ON_TIME, ME1_ACC_ON_TIME, ME2_ACC_ON_TIME

where

AVG_ATT_QUAT_Q1	resultant attitude quaternion for the accumulation period - quat. 1
AVG_ATT_QUAT_Q2	resultant attitude quaternion for the accumulation period - quat. 2
AVG_ATT_QUAT_Q3	resultant attitude quaternion for the accumulation period - quat. 3
AVG_ATT_QUAT_Q4	resultant attitude quaternion for the accumulation period - quat. 4
RCS1_ACC_ON_CMDS	number of firings during the accumulation period for RCS1
RCS2_ACC_ON_CMDS	number of firings during the accumulation period for RCS2
RCS3_ACC_ON_CMDS	number of firings during the accumulation period for RCS3
RCS4_ACC_ON_CMDS	number of firings during the accumulation period for RCS4
TCM1_ACC_ON_CMDS	number of firings during the accumulation period for TCM1
TCM2_ACC_ON_CMDS	number of firings during the accumulation period for TCM2
TCM3_ACC_ON_CMDS	number of firings during the accumulation period for TCM3
TCM4_ACC_ON_CMDS	number of firings during the accumulation period for TCM4
ME1_ACC_ON_CMDS	number of firings during the accumulation period for descent thruster 1
ME2_ACC_ON_CMDS	number of firings during the accumulation period for descent thruster 2
RCS1_ACC_ON_TIME	Accumulated ON time during the accumulation period for RCS1 in millisecs.
RCS2_ACC_ON_TIME	Accumulated ON time during the accumulation period for RCS2 in millisecs.
RCS3_ACC_ON_TIME	Accumulated ON time during the accumulation period for RCS3 in millisecs.
RCS4_ACC_ON_TIME	Accumulated ON time during the accumulation period for RCS4 in millisecs.
TCM1_ACC_ON_TIME	Accumulated ON time during the accumulation period for TCM1 in millisecs.
TCM2_ACC_ON_TIME	Accumulated ON time during the accumulation period for TCM2 in millisecs.
TCM3_ACC_ON_TIME	Accumulated ON time during the accumulation period for TCM3 in millisecs.
TCM4_ACC_ON_TIME	Accumulated ON time during the accumulation period for TCM4 in millisecs.
ME1_ACC_ON_TIME	Accumulated ON time during the accumulation period for descent thruster 1 in millisecs.
ME2_ACC_ON_TIME	Accumulated ON time during the accumulation period for descent thruster 2 in millisecs.

3.3.3.4 Deep Impact Mission Additional Data

For the DIF spacecraft the additional data part of a small forces data record consists of the following parameters extracted from the second small forces APID of each pair used for computing delta V, occurring in the order in which they appear in the APID, plus the packet sequence count values for both APIDs in the pair. These data items are separated by commas and appear on the same line as, and after, the primary data.

ADFDIV1ACMTM_SF_B0012, ADFDIV2ACMTM_SF_B0013, ADFDIV3ACMTM_SF_B0014, ADFDIV4ACMTM_SF_B0015, ADFRCS1ACMTM_SF_B0016, ADFRCS2ACMTM_SF_B0017, ADFRCS3ACMTM_SF_B0018, ADFRCS4ACMTM_SF_B0019, ADFACCDVXCC_SF_B0020, ADFACCDVYCC_SF_B0021, ADFACCDVZCC_SF_B0022, ADFACCDVXEME_SF_B0023, ADFACCDVYEME_SF_B0024, ADFACCDVZEME_SF_B0025, ADFACC1_SF_B0027, ADFACC2_SF_B0028, ADFACC3_SF_B0029, ADFACC4_SF_B0030, ADFGLATTERRX_B0305, ADFGLATTERRY_B0306, ADFGLATTERRZ_B0307, PACKET_SEQ_CNT, PREV_PACKET_SEQ_CNT

Where

ADFDIV1ACMTM_SF_B0012	Accumulated Thruster On-Time - Divert 1
ADFDIV2ACMTM_SF_B0013	Accumulated Thruster On-Time - Divert 2
ADFDIV3ACMTM_SF_B0014	Accumulated Thruster On-Time - Divert 3
ADFDIV4ACMTM_SF_B0015	Accumulated Thruster On-Time - Divert 4
ADFRCS1ACMTM_SF_B0016	Accumulated Thruster On-Time - RCS 1
ADFRCS2ACMTM_SF_B0017	Accumulated Thruster On-Time - RCS 2
ADFRCS3ACMTM_SF_B0018	Accumulated Thruster On-Time - RCS 3
ADFRCS4ACMTM_SF_B0019	Accumulated Thruster On-Time - RCS 4
ADFACCDVXCC_SF_B0020	X accumulated delta-v in body frame
ADFACCDVYCC_SF_B0021	Y accumulated delta-v in body frame
ADFACCDVZCC_SF_B0022	Z accumulated delta-v in body frame
ADFACCDVXEME_SF_B0023	X Accumulated delta-v Earth Mean Equator J2000 Inertial frame
ADFACCDVYEME_SF_B0024	Y Accumulated delta-v Earth Mean Equator J2000 Inertial frame
ADFACCDVZEME_SF_B0025	Z Accumulated delta-v Earth Mean Equator J2000 Inertial frame
ADFACC1_SF_B0027	SIRU angle data word 7 - Accelerometer 1 Delta Velocity reading
ADFACC2_SF_B0028	SIRU angle data word 7 - Accelerometer 2 Delta Velocity reading
ADFACC3_SF_B0029	SIRU angle data word 7 - Accelerometer 3 Delta Velocity reading
ADFACC4_SF_B0030	SIRU angle data word 7 - Accelerometer 4 Delta Velocity reading
ADFGLATTERRX_B0305	TCM guidance law attitude error contribution X axis
ADFGLATTERRY_B0306	TCM guidance law attitude error contribution Y axis
ADFGLATTERRZ_B0307	TCM guidance law attitude error contribution Z axis
PACKET_SEQ_CNT	packet sequence count the second packet in the pair from which the delta V was computed
PREV_PACKET_SEQ_CNT	packet sequence count the first packet in the pair from which the delta V was computed

3.3.3.3 Mars Reconnaissance Orbiter Mission Additional Data

For the MRO mission the additional data part of a small forces data record consists of the following parameters, occurring in the order in which they appear in the small forces APID. These data items are separated by commas and appear on the same line as, and after, the primary data.

AVG_ATT_QUAT_Q1, AVG_ATT_QUAT_Q2, AVG_ATT_QUAT_Q3, AVG_ATT_QUAT_Q4, ACS1_ACC_ON_CMDS, ACS2_ACC_ON_CMDS, ACS3_ACC_ON_CMDS, ACS4_ACC_ON_CMDS, ACS5_ACC_ON_CMDS, ACS6_ACC_ON_CMDS, ACS7_ACC_ON_CMDS, ACS8_ACC_ON_CMDS, TCM1_ACC_ON_CMDS, TCM2_ACC_ON_CMDS, TCM3_ACC_ON_CMDS, TCM4_ACC_ON_CMDS, TCM5_ACC_ON_CMDS, TCM6_ACC_ON_CMDS, ACS1_ACC_ON_TIME, ACS2_ACC_ON_TIME, ACS3_ACC_ON_TIME, ACS4_ACC_ON_TIME, ACS5_ACC_ON_TIME, ACS6_ACC_ON_TIME, ACS7_ACC_ON_TIME, ACS8_ACC_ON_TIME, TCM1_ACC_ON_TIME, TCM2_ACC_ON_TIME, TCM3_ACC_ON_TIME, TCM4_ACC_ON_TIME, TCM5_ACC_ON_TIME, TCM6_ACC_ON_TIME

where

AVG_ATT_QUAT_Q1	Resultant attitude quaternion for the accumulation period - quaternion element 1
AVG_ATT_QUAT_Q2	Resultant attitude quaternion for the accumulation period - quaternion element 2
AVG_ATT_QUAT_Q3	Resultant attitude quaternion for the accumulation period - quaternion element 3
AVG_ATT_QUAT_Q4	Resultant attitude quaternion for the accumulation period - quaternion element 4
ACS#_ACC_ON_CMDS	number of firings of each of the eight (8) ACS thrusters during the accumulation period
TCM#_ACC_ON_CMDS	number of firings of each of the six (6) TCM thrusters during the accumulation period
ACS#_ACC_ON_TIME	Accumulated ON time of each of the eight (8) ACS thrusters during the accumulation period
TCM#_ACC_ON_TIME	Accumulated ON time of each of the six (6) TCM thrusters during the accumulation period

4. Sample Small Forces Files

Shown here are made-up examples of SFF data for all missions. The first two and the last two examples are for a "reconstruction" period with velocity data, as indicated by the "R" in the second field. A "P" would appear in this location for a "predict" velocity SFF. The third example is for a Stardust predict accelerations file.

Note that the data records do not have a fixed width format; rather, each data item is simply comma delimited from the previous item.

Note that in SDU predict files for both delta-V and acceleration the last four data items are given in scientific notation.

The data portion of each file begins with data record number one.

4.1 Example Reconstruction Small Forces File for Mars Polar Lander

MISSION_NAME = M98

SPACECRAFT_NAME = M98

DSN_SPACECRAFT_ID = 116

PRODUCTION_TIME = 1999-03-13 14:01:18

PRODUCER_ID = NAIF/JPL

$$EOH

1, R, ... etc.

2, R, ... etc.

...

2161, R, 1999-03-10 12:22:36, 1999-03-06 13:00:00.000, 1999-03-06 13:00:02.008, 2.008, 0, 0.002, 0.000, 0.000

2162, R, 1999-03-10 12:22:36, 1999-03-07 01:00:43.560, 1999-03-07 01:00:44.061, 0.500, 0, 0.000, 0.003, 0.000

2163, R, 1999-03-10 12:22:36, 1999-03-07 13:01:27.120, 1999-03-07 13:01:28.121, 1.001, 0, 0.002, 0.001, 0.000

2164, R, 1999-03-10 12:22:36, 1999-03-08 01:02:10.680, 1999-03-08 01:02:12.182, 1.501, 0, 0.000, 0.000, 0.004

2165, R, 1999-03-10 12:22:36, 1999-03-08 13:02:54.240, 1999-03-08 13:02:56.242, 2.002, 0, 0.002, 0.000, 0.001

2166, R, 1999-03-10 12:22:36, 1999-03-09 01:03:37.800, 1999-03-09 01:03:40.303, 2.502, 0, 0.000, 0.003, 0.000

2167, R, 1999-03-10 12:22:36, 1999-03-09 13:04:21.360, 1999-03-09 13:04:24.363, 3.003, 0, 0.000, 0.002, 0.002

2168, R, 1999-03-10 12:22:36, 1999-03-10 01:05:04.920, 1999-03-10 01:05:08.424, 3.503, 0, 0.003, 0.000, 0.000

2169, R, 1999-03-10 12:22:36, 1999-03-10 13:05:48.480, 1999-03-10 13:05:51.484, 3.004, 0, 0.003, 0.000, 0.000

2170, R, 1999-03-13 14:01:18, 1999-03-11 01:06:32.040, 1999-03-11 01:06:36.545, 4.504, 0, 0.001, 0.001, 0.000

2171, R, 1999-03-13 14:01:18, 1999-03-11 13:07:15.600, 1999-03-11 13:07:18.605, 3.000, 0, 0.000, 0.002, 0.000

2172, R, 1999-03-13 14:01:18, 1999-03-12 01:07:59.160, 1999-03-12 01:08:01.666, 3.505, 0, 0.000, 0.000, 0.005

2173, R, 1999-03-13 14:01:18, 1999-03-12 13:08:42.720, 1999-03-12 13:08:44.726, 2.006, 0, 0.001, 0.002, 0.001

...

etc.

4.2 Example Reconstruction Small Forces File for Stardust

This example is for a SFF containing delta-V information. In this example the "additional data" portion of each record is not shown due to the length of the data.

MISSION_NAME = Stardust

SPACECRAFT_NAME = Sdu

DSN_SPACECRAFT_ID = 29

PRODUCTION_TIME = 2001-11-10 13:04:21

PRODUCER_ID = NAIF/JPL

$$EOH

1, R, ...

...

7821, R, 2001-11-07 13:00:00, 2001-11-06 13:00:00.000, 2001-11-07 01:00:00.000, 43200.000, 0.003, 0.012, 0.006, 0.002

7822, R, 2001-11-08 01:00:43, 2001-11-07 01:00:43.560, 2001-11-07 13:00:43.560, 43200.000, 0.002, 0.002, 0.009, 0.001

7823, R, 2001-11-08 13:01:27, 2001-11-07 13:01:27.120, 2001-11-08 01:01:27.120, 43200.000, 0.004, 0.021, 0.009, 0.009

7824, R, 2001-11-09 01:02:10, 2001-11-08 01:02:10.680, 2001-11-08 13:02:10.680, 43200.000, 0.003, 0.001, 0.023, 0.001

7825, R, 2001-11-09 13:02:54, 2001-11-08 13:02:54.240, 2001-11-09 01:02:54.240, 43200.000, 0.001, 0.003, 0.002, 0.001

7826, R, 2001-11-10 01:03:37, 2001-11-09 01:03:37.800, 2001-11-09 13:03:37.800, 43200.000, 0.002, 0.009, 0.002, 0.003

7827, R, 2001-11-10 13:04:21, 2001-11-09 13:04:21.360, 2001-11-10 01:04:21.360, 43200.000, 0.004, 0.000, 0.011, 0.009

...

etc.

4.3 Example Predict Small Forces File with Acceleration Data for Stardust

This example is for a SFF containing acceleration information, as indicated by the use of the RECTYPE values of X and A (for discontinuous and continuous data, respectively).

MISSION_NAME = Stardust

SPACECRAFT_NAME = Sdu

DSN_SPACECRAFT_ID = 29

PRODUCTION_TIME = 1998-04-22 13:22:52

PRODUCER_ID = MD/JPL

$$EOH

1, X, 1998-04-22 13:22:52, 1999-02-06 21:43:04.000, 1999-02-07 21:43:04.000, 86400.000, -0.20006298E-07, 0.28752638E-08, -0.46155846E-07, -0.19802151E-07

2, A, 1998-04-22 13:22:52, 1999-02-07 21:43:04.000, 1999-02-08 21:43:04.000, 86400.000, -0.20014215E-07, 0.39173617E-08, -0.46038776E-07, -0.19946570E-07

3, A, 1998-04-22 13:22:52, 1999-02-08 21:43:04.000, 1999-02-09 21:43:04.000, 86400.000, -0.20017264E-07, 0.49553662E-08, -0.45947732E-07, -0.19945546E-07

4, A, 1998-04-22 13:22:52, 1999-02-09 21:43:04.000, 1999-02-10 21:43:04.000, 86400.000, -0.20015754E-07, 0.59894216E-08, -0.45834364E-07, -0.19913633E-07

5, A, 1998-04-22 13:22:52, 1999-02-10 21:43:04.000, 1999-02-11 21:43:04.000, 86400.000, -0.20009746E-07, 0.70185717E-08, -0.45693879E-07, -0.19862674E-07

6, A, 1998-04-22 13:22:52, 1999-02-11 21:43:04.000, 1999-02-12 21:43:04.000, 86400.000, -0.19999274E-07, 0.80416247E-08, -0.45525137E-07, -0.19796065E-07

7, A, 1998-04-22 13:22:52, 1999-02-12 21:43:04.000, 1999-02-13 21:43:04.000, 86400.000, -0.19984370E-07, 0.90573241E-08, -0.45327907E-07, -0.19715219E-07

8, A, 1998-04-22 13:22:52, 1999-02-13 21:43:04.000, 1999-02-14 21:43:04.000, 86400.000, -0.19965066E-07, 0.10064401E-07, -0.45102311E-07, -0.19620898E-07

...

etc.

4.4 Example Reconstruction Small Forces File for Genesis

This example is for a reconstructed Genesis SFF file. It contains both "primary" and "additional" data portions of each record.

MISSION_NAME = GNS

SPACECRAFT_NAME = Gns

DSN_SPACECRAFT_ID = 47

PRODUCTION_TIME = 2002-12-06 16:54:47

PRODUCER_ID = GNS_DMA/JPL

$$EOH

1, R, …

…

271, R, 2000-12-06 16:54:47, 2001-02-10 23:47:51.794, 2001-02-10 23:50:01.341, 129.547, 0.000000, 0.23491000, -0.16578500, -0.07240200, 635.812000, 480.234540, SPIN_CONTROL, CLOSED, CLOSED, CLOSED, CLOSED, STOWED, UNKNOWN, STOWED, UNKNOWN,STOWED, UNKNOWN, STOWED, UNKNOWN, 0.792290, -0.559148, -0.244192, 0.547001, 0.792329, -0.559102, -0.244172, 0.953446, 12, 14, TRUE, 170576934440

272, R, 2000-12-06 16:54:47, 2001-02-11 04:48:31.794, 2001-02-11 04:48:31.341, -0.453, 0.000000, 0.23491000, -0.16578500, -0.07240200, 635.812000, 480.234540, SPIN_CONTROL, CLOSED, CLOSED, CLOSED, CLOSED, STOWED, UNKNOWN, STOWED, UNKNOWN, STOWED, UNKNOWN, STOWED, UNKNOWN, 0.792290, -0.559148, -0.244192, 0.547001, 0.792329, -0.559102, -0.244172, 0.953446, 14, 16, TRUE, 170581934555

…

4.5 Example Reconstruction Small Forces File for Mars Odyssey 2001

This example is for a SFF containing delta-V information. In this example the "additional data" portion of each record is not shown due to the length of the data.

MISSION_NAME = M01

SPACECRAFT_NAME = Or1

DSN_SPACECRAFT_ID = 53

PRODUCTION_TIME = 2001-04-12 00:18:57

PRODUCER_ID = M01NAV

$$EOH

1, R, …

…

324, R, 2001-04-12 00:18:57, 2001-04-07 15:14:45.461, 2001-04-07 15:24:45.846, 600.385, 0.000000, -0.00415154, -0.00172720, -0.03472536, 0.11045263708,-0.32217410207, -0.94020485878, 0.00434873765, 171807857430

325, R, 2001-04-12 00:18:57, 2001-04-07 15:24:45.459, 2001-04-07 15:34:45.852, 600.393, 0.000000, 0.00069324, -0.01533687, 0.01435403, 0.61095130444, 0.74198502302, 0.24058885872, 0.13532844186, 171808011032

326, R, 2001-04-12 00:18:57, 2001-04-07 15:34:45.458, 2001-04-07 15:44:45.858, 600.401, 0.000000, -0.00143774, -0.00837084, 0.00414622, 0.96132498980, 0.13071690500, 0.15366849303, 0.18749238551, 171808164634

…

4.6 Example Reconstruction Small Forces File for Deep Impact Flyby Spacecraft

This example is for a reconstructed DIF delta-V SFF file. It contains both "primary" and "additional" data portions of each record.

MISSION_NAME = Di

SPACECRAFT_NAME = Dif

DSN_SPACECRAFT_ID = 140

PRODUCTION_TIME = 2004-11-24 18:11:16

PRODUCER_ID = NAIF/JPL

$$EOH

…

2, R, 2004-11-24 18:11:16, 2005-01-19 16:13:32.051, 2005-01-19 16:13:36.051, 4.000, 0.000000, 0.00048518, 0.00620842, 0.00014332, 0.000000, 0.000000, 0.000000, 0.000000, 2.346500, 0.000000, 0.000000, 2.364000, -1.67082179, -8.91650486, 0.27610654, -1.67059493, -8.91652870, 0.27610868, 740, 65405, 64459, 65338, 0.0000000000000000, 0.0000000000000000, 0.0000000000000000, 509, 506, 40812326878

3, R, 2004-11-24 18:11:16, 2005-01-19 16:13:36.051, 2005-01-19 16:13:40.051, 4.000, 0.000000, 0.00039268, 0.00327969, 0.00006500, 0.000000, 0.000000, 0.000000, 0.000000, 2.903500, 0.000000, 0.000000, 2.924500, -1.67072034, -8.91319656, 0.27616903, -1.67020226, -8.91324902, 0.27617368, 935, 65331, 64086, 65244, 0.0000000000000000, 0.0000000000000000, 0.0000000000000000, 512, 509, 40812327902

4, R, 2004-11-24 18:11:16, 2005-01-19 16:13:40.051, 2005-01-19 16:13:44.051, 4.000, 0.000000, 0.00021136, 0.00115871, 0.00003761, 0.000000, 0.000000, 0.000000, 0.000000, 3.102500, 0.000000, 0.000000, 3.127500, -1.67068875, -8.91201496, 0.27620521, -1.66999090, -8.91209030, 0.27621129, 1014, 65257, 63839, 65164, 0.0000000000000000, 0.0000000000000000, 0.0000000000000000, 515, 512, 40812328926

…

4.7 Example Reconstruction Small Forces File for Mars Reconnaissance Orbiter

This example is for a reconstructed MRO delta-V SFF file. It contains both "primary" and "additional" data portions of each record.

MISSION_NAME = MRO

SPACECRAFT_NAME = Mro

DSN_SPACECRAFT_ID = 74

PRODUCTION_TIME = 2005-07-06 19:54:49

PRODUCER_ID = MRONAV/JPL

$$EOH

1, R, 2005-07-06 19:54:49, 2005-09-08 19:03:56.182, 2005-09-08 19:05:37.596, 101

.414, 0.000000, 0.000000006570, -0.000000035506, 0.000000069052, 0.84754568338,

0.15530408919, -0.36973485351, 0.34762489796, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0

, 0, 0, 0, 100, 0, 100, 0, 100, 0, 100, 0, 0, 0, 0, 0, 0, 207532412522

2, R, 2005-07-06 19:54:49, 2005-09-08 19:05:37.182, 2005-09-08 19:05:37.698, 0.5

16, 0.000000, 0.000000006570, -0.000000035506, 0.000000069052, 0.84754562378, 0.

15530416369, -0.36973488331, 0.34762495756, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0,

0, 0, 0, 100, 0, 100, 0, 100, 0, 100, 0, 0, 0, 0, 0, 0, 207532412548

3, R, 2005-07-06 19:54:49, 2005-09-08 19:05:37.182, 2005-09-08 19:05:37.795, 0.6

13, 0.000000, 0.000000006570, -0.000000035506, 0.000000069052, 0.84754109383, 0.

15530833602, -0.36974099278, 0.34762775898, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0,

0, 0, 0, 100, 0, 100, 0, 100, 0, 100, 0, 0, 0, 0, 0, 0, 207532412573

4, R, 2005-07-06 19:54:49, 2005-09-08 19:05:37.182, 2005-09-08 19:05:37.897, 0.7

15, 0.000000, 0.000000009258, 0.000000028167, -0.000000067489, 0.84754055738, 0.

15530809760, -0.36974206567, 0.34762799740, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0,

0, 0, 0, 72, 0, 84, 0, 96, 0, 80, 0, 0, 0, 0, 0, 0, 207532412599

…

4.8 Example Predicted Small Forces File for Mars Reconnaissance Orbiter

This example is for a predicted MRO delta-V SFF file. Predicted MRO SFF files contain only "primary" data items.

MISSION_NAME = MRO

SPACECRAFT_NAME = Mro

DSN_SPACECRAFT_ID = 74

PRODUCTION_TIME = 2005-07-06 20:10:20

PRODUCER_ID = NAIF/JPL

$$EOH

1, P, 2005-07-06 20:10:20, 2007-12-05 17:00:12.784, 2007-12-05 17:00:12.886, 0.1

02, 0.000000, 0.000000673258, 0.000000739408, -0.000000000000, 225623337396

2, P, 2005-07-06 20:10:20, 2007-12-05 17:00:32.585, 2007-12-05 17:00:32.687, 0.1

02, 0.000000, 0.000000673258, 0.000000739408, -0.000000000000, 225623342465

3, P, 2005-07-06 20:10:20, 2007-12-05 17:00:42.784, 2007-12-05 17:00:42.886, 0.1

02, 0.000000, 0.000000673258, 0.000000739408, -0.000000000000, 225623345076

4, P, 2005-07-06 20:10:20, 2007-12-05 17:01:02.487, 2007-12-05 17:01:02.585, 0.0

98, 0.000000, 0.000000673258, 0.000000739408, -0.000000000000, 225623350119

…

Version	Date	Reason
1.0	06-15-98	First draft, for review
1.1	09-05-98	Updated after first review
1.2	10-25-98	Updated after second review
1.3	11-09-98	Updated after third review
1.4	03-16-99	Updated to reflect optional addition of the SPICE DP SCLK
1.5	10-22-00	Updated for Genesis
1.6	01-08-01	Updated for Mars Odyssey 2001 Orbiter
1.7	02-24-01	Updated after GNS/M01 review
1.8	03-16-01	Replaced OPENED with OPEN in optional GNS fields
1.9	08-20-04	Updated for Deep Impact and MRO
2.0	09-02-04	Added clarification regarding sign of DMASS
2.1	11-24-04	Changed DI sections to match SFF updated for new packet format
2.2	07-29-05	Updated to cover predicted MRO SFF; updated reconstructed MRO SFF example;

Table of Contents

List of Acronyms

Change History

1. General Description

1.1 Purpose

1.2. Scope

1.3 Applicable Documents

2. Method of Generation

2.1 Predict Mode

2.2 Reconstruction Mode

2.3 Merging Predict and Reconstruction Delta-V Files

3. Detailed Data Object Definition

3.1 General Structure

3.2 Header Section Structure

3.3 Data Section Structure

3.3.1 Data Record Structure Overview

3.3.2 Data Record Primary Data Structure

3.3.3 Data Record Additional Data Structure

3.3.3.1 Stardust Mission Additional Data

3.3.3.2 Genesis Mission Additional Data

3.3.3.3 Mars Odyssey 2001 Mission Additional Data

3.3.3.4 Deep Impact Mission Additional Data

3.3.3.3 Mars Reconnaissance Orbiter Mission Additional Data

4. Sample Small Forces Files

4.1 Example Reconstruction Small Forces File for Mars Polar Lander

4.2 Example Reconstruction Small Forces File for Stardust

4.3 Example Predict Small Forces File with Acceleration Data for Stardust

4.4 Example Reconstruction Small Forces File for Genesis

4.5 Example Reconstruction Small Forces File for Mars Odyssey 2001

4.6 Example Reconstruction Small Forces File for Deep Impact Flyby Spacecraft

4.7 Example Reconstruction Small Forces File for Mars Reconnaissance Orbiter

4.8 Example Predicted Small Forces File for Mars Reconnaissance Orbiter