IO-EK-001 29 March 2005
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PROJECT CASSINI
SOFTWARE INTERFACE SPECIFICATION
COVER SHEET
SIS Number: IO-EK-001
SIS Revision: Revision C
Date: 29 March 2005
SIS NAME: EKernel Files
PURPOSE OF INTERFACE: EKernel files containing sequence and science plan
 data.
DATA FLOW:
FROM TO DATA OBJECT MEDIUM
IO GDSE Binary File Electronic
APPLICABLE Documents:
Related OIAs: IO-OIA-013
IO-OIA-040
SIS Coordinator: Diane Conner
APPROVAL NAME DATE
GDSE T. Sesplaukis ____________________________________
NAIF Manager C. Acton ____________________________________
IO Team Manager S. Linick ____________________________________
 
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Document Change Log:
Version Change Description Date
Initial Initial Release 5 March 2002
Rev A.
Reflect design change that
eliminates IEB description
files.
8 August 2002
Rev B.
Reflect design change that
eliminates IEB expansion
files.
Also modified the
database schema.
Included expanded schema
definitions.
Updated based upon
comments from Chuck
Acton.
9 September 2003
Rev C.
Added Long_value column
to status table
Added additional
descriptive text.
Added filenaming
conventions in 4.1.
Updated schema diagram.
23 March 2005
 
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1. GENERAL DESCRIPTION .................................................
........ 4
1.1. Purpose of Document ...............................................
.......................................4
1.2. Scope .............................................................
...................................................4
1.3. Applicable Documents...............................................
......................................4
1.4. Functional Description.............................................
........................................5
1.4.1. Data Source, Destination and Transfer Method ....................
......................6
1.4.2. Pertinent Relationships with Other Interfaces ...................
.........................7
1.4.3. Labeling and Identification .....................................
......................................7
1.4.4. Assumptions and Constraints......................................
................................7
2. ENVIRONMENT..........................................................
................ 7
2.1. Hardware Characteristics and Limitations ..........................
...........................7
2.2. Interface Medium and Characteristics ..............................
..............................7
2.3. Input/Output Protocols ............................................
........................................7
2.4. Failure Protection, Detection and Recovery Features................
...................7
2.4.1. Backup Requirements..............................................
.....................................8
2.4.2. Security/Integrity Measures......................................
....................................8
2.5. End-of-File (or Medium) Conventions................................
.............................8
2.6. Utility Programs...................................................
.............................................8
3. DATA FLOW CHARACTERISTICS............................................
 9
3.1. Operational Characteristics........................................
.....................................9
3.1.1. Generation Method and Frequency..................................
............................9
3.1.2. Time Span of Product ............................................
.......................................9
3.2. Data Volume .......................................................
..............................................9
3.3. Flow Rate .........................................................
.................................................9
4. DETAILED DATA OBJECT DEFINITION................................. 10
4.1. Structure and Organization Overview................................
...........................10
4.2. Data Format and Definition.........................................
...................................19
 
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1. GENERAL DESCRIPTION
1.1. Purpose of Document
The purpose of this document is to describe the format, content, and org
anization
of SPICE EKernel files specific to the Cassini Project.
1.2. Scope
This document describes ESQ (Sequence), ESP (Science Plan), and ENB
(notebook) components of Cassini SPICE EKernel files.
1.3. Applicable Documents
IO-OIA-040, EKernel IEB and Dictionary Input Files (EKSEQ)
IO-OIA-013, EKernel Files
Multimission Software Interface Specification (SIS) SPICE Events Kernel,
 
NAIF Document No. 371, Version 1.0,
ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/SISs/
SPICE EKernel Tutorials found at
ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/Tutorials or by contacting
 
Chuck Acton of the PDS NAIF node.
EKernel Required Reading, NAIF Doc. No. 368, included in the NAIF
Toolkit
DAS Required Reading, NAIF Doc. No. 367, included in the NAIF Toolkit
Cassini Program SPICE Events Kernel System Design Document, D-
22965
 
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1.4. Functional Description
The SPICE EKernel is a repository for science plans, instrument and spac
ecraft
commands, and experimenter's notebook information that can be used by
scientists interpreting data returned from spacecraft instruments. The E
Kernel
will be archived at the NAIF Node of the Planetary Data System (PDS) to
preserve the mission science plan and sequence activity information. An
overview of the entire EKernel system is provided in SPICE tutorials (Se
e
applicable documents).
The initial Cassini EKernel system design is documented in Cassini Progr
am
SPICE Events Kernel System Design document, D-22965. Some of the initial
 
design changed after the system design was documented. Changes in the
design are reflected in this SIS.
Mission operations teams and scientists provide EKernel data. Some EKern
el
data are in the form of predicts, while others consist of after-the-fact
 information
referred to as "as-flown." The EKernel has three distinct components. Fo
r
Cassini, as with other projects, the contents of these components are
customized.
SCIENCE PLAN (ESP) Contains scientific objectives for observations
scheduled over a specified period of time.
SEQUENCE (ESQ) Contains spacecraft and instrument commands
intended to carry out the observation science objectives of the mission
(as partly
described in the ESP component), command notes, mechanical noise events,
 
and spacecraft and instrument state information.
NOTEBOOK (ENB) Contains notes about anomalies, observations, or
other after-the-fact event information that may be of interest to other
scientists or
project personnel.
 
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1.4.1. Data Source, Destination and Transfer Method
EKernel files are created from a variety of data sources depending upon
the
component as shown in the table below.
A project repository will be used to deliver files to the NAIF provided
SPICE
Server as described in OIA-IO-013.
Input FILE TYPE
Input DESCRIPTION
EKernel TABLE
EKernel
Component
SIS/OIAs
PEF
Predicted Events File from the
sequence team. This file,
along with a command
dictionary EK, are used to
create a background ESQ EK.
CASSINI_CMD
CASSINI_STATUS
CASSINI_NOTES
ESQ OIA SVT-022
(As-flown)
OIA SVT-004
(Predict)
3-291 command
dictionary XML
file.
The 3-291 commands XML file from
SCO CORE system.
CASSINI_CMD_DICT
ESQ OIA IO-040
SIS IO-EK-002
Noise events
XML files
Currently only supplied by ISS.
XML file is created by
accessing MIPS operational
image processing database.
CASSINI_NOISE_EVENTS
ESQ OIA IO-040
SIS IO-EK-002
Observations and
Requests
Submitted by all teams through
CIMS (Cassini Information
Management System)
database. Records are
extracted from the database
containing detailed science
requests and high-level
observation plans.
CASSINI_SP_REQUEST
CASSINI_SP_OBSERVATION
CASSINI_SP_REQ_OBS
ESP OIA IO-054
CIMS DTDs &
Toolkit
Experimenter
Notes
Submitted by all teams through
CIMS.
CASSINI_ENB_REQUEST
CASSINI_ENB_OBSERVATION
CASSINI_ENB_REQ_OBS
ENB OIA IO-054
CIMS DTDs &
Toolkit
 
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1.4.2. Pertinent Relationships with Other Interfaces
A SPICE EKernel file can be accessed using the NAIF toolkit utility
INSPEKT and SPICE library subroutines.
1.4.3. Labeling and Identification
EK file SFDU K-headers will be created and stored in DOM as detached
files with keyword values shown below. The SFDU header will also be
included in the EKernel comment area.
Keyword Value Type
MISSION_NAME = CASSINI
SPACECRAFT_NAME = CASSINI
DATA_SET_ID = EKERNEL
FILENAME = CHARACTER
PRODUCT_CREATION_TIME = UTC TIME
PRODUCER_ID = CHARACTER
SEQ_NUMBER = CHARACTER
START_TIME = UTC TIME
STOP_TIME = UTC TIME
NOTE = CHARACTER 256
1.4.4. Assumptions and Constraints
None.
2. ENVIRONMENT
2.1. Hardware Characteristics and Limitations
Not applicable.
2.2. Interface Medium and Characteristics
File transfer to project file repository
2.3. Input/Output Protocols
Not applicable.
2.4. Failure Protection, Detection and Recovery Features
Standard file repository procedures.
 
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2.4.1. Backup Requirements
Standard file repository procedures.
Security/Integrity Measures
Files will be checked for format integrity using NAIF subroutines.
2.5. End-of-File (or Medium) Conventions
See NAIF Document No. 371, Version 1.0
2.6. Utility Programs
The NAIF Toolkit utility INSPEKT can be used to access information conta
ined
within EKernel files. NAIF Toolkit EKernel reader subroutines can also b
e
utilized in a user's own program to access EKernel data. For user conven
ience,
an INSPEKT startup file will be created and provided to users. This file
 will
evolve as new queries are developed. A final Cassini INSPEKT startup fil
e will
be archived with the kernels at PDS.
 
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3. DATA FLOW CHARACTERISTICS
3.1. Operational Characteristics
3.1.1. Generation Method and Frequency
Described in OIA-IO-013.
3.1.2. Time Span of Product
Described in OIA-IO-013.
3.2. Data Volume
Described in OIA-IO-013.
3.3. Flow Rate
Not applicable.
 
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4. DETAILED DATA OBJECT DEFINITION
4.1. Structure and Organization Overview
The EKernel is a database stored in a collection of files. One or more t
ables may
be stored in a single Ekernel file.
Tables are logically grouped into files if their data source is the same
 and if joins
can be done between tables. Note that there are joins that can be made
between tables that are in different files, i.e. the CASSINI_CMD and
CASSINI_ENB_REQ_OBS tables can be joined by REQUEST_ID, and
CASSINI_CMD and CASSINI_CMD_DICT tables can be joined by COMMAND,
PARAMETER_NAME AND PARAMETER_INDEX.
With the exception of the ESQ_COMMAND file type, each file type is creat
ed for
every sequence. The ESQ_COMMAND file type is created for each command
database version delivered to the project.
The below table shows the file types, the tables they contain, and their
 filenaming
convention.
EKernel File Type Table(s) Filenaming
ESQ
Commands and
Notes
CASSINI_CMD
CASSINI_NOTE
[Sequencenumber]_cmd_[state][v].[ext]
Where:
[Sequencenumber]: SVT sequence number
[state] p: Predicted Events based upon completed sequence
f: Flown events with RT changes incorporated
[v]: Version letter from a - z
[ext]: xes for transfer format
bes for IEEE binary format
ESQ
Subsystem Status
CASSINI_STATUS [Sequencenumber]_status_[state][v].[ext]
Where:
[Sequencenumber]: SVT sequence number
[state] p: Predicted Events based upon completed sequence
f: Flown events with RT changes incorporated
[v]: Version letter from a - z
[ext]: xes for transfer format
bes for IEEE binary format
ESQ
Mechanical noise
events
CASSINI_NOISE_EVENTS [Sequencenumber]_[subsystemid]noise_[v].[ext]
Where:
[Sequencenumber]: SVT sequence number
[subsystemid]: subsystem id (2 digit number)
[v]: Version letter from a - z
[ext]: xes for transfer format
bes for IEEE binary format
 
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EKernel File Type Table(s) Filenaming
ESQ
Command
Dictionary
CASSINI_CMD_DICT [cmddbVersion].[ext]
Where:
[cmddbVersion]: command database version
[ext]: xbd for transfer format
bdb for IEEE binary format
ESP
Science Plan
CASSINI_SP_REQUEST
CASSINI_SP_OBSERVATION
CASSINI_SP_REQ_OBS
[Sequencenumber]_[source][phase][v].[ext]
Where:
[Sequencenumber]: SVT sequence number
[source]: CIMS, or XML file
[phase]: Sequence Phase (SSUP is the latest)
[v]: Version letter from a - z
[ext]: xep for transfer format
bep for IEEE binary format
ENB
Experimenter's
Notebook
CASSINI_ENB_REQUEST
CASSINI_ENB_OBSERVATION
CASSINI_ENB_REQ_OBS
[Sequencenumber]_[source][phase][v].[ext]
Where:
[Sequencenumber]: SVT sequence number
[source]: CIMS, or XML file
[phase]: Sequence Phase (SSUP is the latest)
[v]: Version letter from a - z
[ext]: xen for transfer format
ben for IEEE binary format
 
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DICTIONARY_VERSION
DESCRIPTION
PARAMETER_RANGE
PARAMETER_TYPE
PARAMETER_INDEX
PARAMETER_NAME
COMMAND
SUBSYSTEM
CASSINI_CMD_DICT (ESQ)
END_TIME
SOURCE_FLAG
BEGIN_TIME
EVENT
COMMAND_EXEC_TIME
CASSINI_NOISE_EVENTS
(ESQ)
SEQUENCE
OBSERVATION_TITLE
SUBSYSTEM
NOTES
OBS_DESCRIPTION
SCIENCE_OBJECTIVE
OBSERVATION_ID
CASSINI_SP_OBSERVATION
(ESP)
DICTIONARY_VERSION
REQUEST_ID
LONG_VALUE
PARAMETER_INDEX
ENTRY_ID
VALUE_FLAG
INT_VALUE
DP_VALUE
CHR_VALUE
PARAMETER_NAME
COMMAND
TIME
CASSINI_CMD
(ESQ)
SEQUENCE
OBSERVATION_ID
REQUEST_ID
CASSINI_SP_REQ_OBS
(ESP)
REQUEST_ID
LONG_VALUE
ATTRIBUTE_INDEX
ENTRY_ID
CHR_VALUE
ATTRIBUTE_NAME
TIME
CASSINI_NOTE
(ESQ)
BEGIN_TIME
LONG_VALUE
PARAMETER_VALUE
PARAMETER_NAME
SUBSYSTEM
CASSINI_STATUS
(ESQ)
SECONDARY_POINTING
BEGIN_TIME
END_TIME
SEQUENCE
REQUEST_TITLE
SUBSYSTEM
REQ_DESCRIPTION
PRIMARY_POINTING
POINTING_AGREEMENT
REQUEST_ID
CASSINI_ SP_REQUEST
(ESP)
OBSERVATION_TITLE
SUBSYSTEM
OBS_AS_FLOWN_NOTES
SEQUENCE
OBSERVATION_ID
CASSINI_ENB_OBSERVATION
(ENB)
SEQUENCE
OBSERVATION_ID
REQUEST_ID
CASSINI_ENB_REQ_OBS
(ENB)
REQUEST_TITLE
SUBSYSTEM
REQ_AS_FLOWN_NOTES
SEQUENCE
REQUEST_ID
CASSINI_ENB_REQUEST
(ENB)
1:M
M:M
M:M
M:M
M:M
1:M
1:M
M:1
M:1
M:1
M:1
1:M
1:M
END_TIME
1:M
 
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Expanded Schema Definition:
TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
SUBSYSTEM String of Length
32
N Y Name of subsystem
COMMAND String of Length
32
N Y Name of command
PARAMETER_NAME String of Length
32
N Y Name of the parameter
PARAMETER_INDEX Integer N Y Index of the parameter (Specifies order of
parameter_names)
CASSINI_CMD_DICT
PARAMETER_TYPE String of Length
32
Y N Describes the data type for each parameter. Case
sensitive standard values allowed for this element are:
Unsigned Integer - an unsigned integer number
(abbreviated in the table as Unsign Integer)
Signed Integer - a signed integer number
String - A string of characters to be translated into binary
either directly or via a user hook
Hex   Hex value
Absolute Time - Absolute time in the form yyyydddThh:
mm:ss.fff where
yyyy = the year
ddd = the day of the year
(January 1 = 001)
hh = hours
mm = minutes
ss = seconds
.fff = fraction of seconds
Relative Time (Duration) - Relative time in the form
hh:mm:ss.fff where
hh = hours
mm = minutes
ss = seconds
 
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TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
.fff = fraction of seconds
List   The number of items in the list may or may not be
a fixed number. The values for parameters of this type
are enclosed in braces  [ ]  in the PEF.
Enumerated - these data are typically sets of discrete
values. For example, {0,10,100} is an enumerated data
set as opposed to {0..100}, which is a set of continuous
data.
Real   Real number.
PARAMETER_RANGE Variable array of
Strings of length
80.
Y N Range of valid values for the parameter.
DESCRIPTION Variable array of
Strings of length
80.
N N Subsystem/Command/Parameter description
DICTIONARY_VERSION String of Length
32
N Y Command dictionary version.
TIME Time N Y Command time tag from Predicted Events File (PEF).
COMMAND Variable Length
String
N Y Command name.
PARAMETER_NAME Variable Length
String
N Y Parameter name. Parameter names are taken from the
command dictionary
CHR_VALUE Variable Length
String
Y Y Value of the parameter as a character string.
DP_VALUE Double Y Y Value of the parameter as a double precision number
(if
character string can be parsed as a double precision
number).
INT_VALUE Integer Y Y Value of the parameter in integer number (if chara
cter
string can be parsed as an integer number).
CASSINI_CMD
VALUE_FLAG Char N Y Single character flag showing which values are prese
nt
for current parameter. It can be set to ' 'C', 'D','I' or 'A'.
These values stand for: 'C' -- only character value is
available. 'D' -- character and DP values are available. 'I'
-- character, DP and INT values are available. 'A' -- only
"long value" is available.
 
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TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
ENTRY_ID Variable Length
String
N Y Character string which has the same value for all EK
table records representing a single command record
from PEF file. Constructed as <PEF SEQ ID>:<CMD
line number in PEF file>. If <PEF SEQ ID> string wasn't
available from PEF file header, it's replaced with some
random string that will be the same for all records from a
single PEF file.
PARAMETER_INDEX Integer N Y Index of the parameter for a command which s
pecifies
the order of parameters for a specific command.
LONG_VALUE Variable array of
Strings of length
80.
Y N Values that do not fit into CHR_VALUE field.
REQUEST_ID Variable Length
String
N Y The command request id string from the PEF.
DICTIONARY_VERSION String of Length
32
N Y Version of the command dictionary used to create this
table.
TIME Time N Y Time of the entry from PEF file.
ATTRIBUTE_NAME Variable Length
String
N Y Attribute names are set to
some fixed values defined by PEF specification. These
values are: PROCESSOR_ID,SEQUENCE_ID, and
NOTE_TEXT
CHR_VALUE Variable Length
String
Y Y Value of the attribute in character string.
ENTRY_ID Variable Length
String
N Y Character string which has the same value for all EK
table records representing a single command record
from PEF file. Constructed as <PEF SEQ ID>:<CMD
line number in PEF file>. If <PEF SEQ ID> string wasn't
available from PEF file header, it's replaced with some
random string that will be the same for all records from a
single PEF file.
ATTRIBUTE_INDEX Integer N Y Index of the attribute in a note record from
 PEF file.
LONG_VALUE Variable array of
Strings of length
80.
Y N Character string array containing an "80 characters"
wrapped long character value that couldn't fit into
CHR_VALUE. To get real parameter value from this
array all array elements must be concatenated together.
CASSINI_NOTE
REQUEST_ID Variable Length
String
N Y The command request id string from the PEF.
 
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TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
SUBSYSTEM String of Length
32
N Y Name of subsystem
PARAMETER_NAME String of Length
32
N Y Parameter names are taken from corresponding PEF
status records.
PARAMETER_VALUE Variable Length
String
N Y Value of the attribute in character string.
LONG_VALUE Variable array of
Strings of length
80.
Y N Values that do not fit into the PARAMETER_VALUE
field.
BEGIN_TIME Time N Y The time when this parameter obtained the value
specified in the PARAMETER_VALUE field.
CASSINI_STATUS
END_TIME Time N Y The time when this parameter lost the value specified
in
the PARAMETER_VALUE field.
COMMAND_EXEC_TIME Time N Y The execution time of the command that caused
 a
mechanical noise event.
EVENT Variable Length
String
N N Type of mechanical noise event.
BEGIN_TIME Time N Y The time when the noise event started to occur.
END_TIME Time N Y The time when the noise event ended.
CASSINI_NOISE_EV
ENTS
SOURCE_FLAG Variable Length
String
N N Indicates whether the source data is predict or actual/asflown
data.
SUBSYSTEM String of Length
32
N Y Name of subsystem.
OBSERVATION_ID Variable Length
String
N Y An EK unique internal identifier that created by
concatenating a sequence and a number.
OBSERVATION_TITLE Variable Length
String
N Y Observation title.
SEQUENCE String of Length
32
N Y Sequence identifier string.
SCIENCE_OBJECTIVE Variable array of
Strings of length
80.
Y N Science objectives for this observation.
OBS_DESCRIPTION Variable array of
Strings of length
80.
Y N General description of this observation.
CASSINI_SP_OBSE
RVATION
NOTES Variable array of
Strings of length
Y N Additional notes for this observation.
 
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TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
80.
SUBSYSTEM String of Length
32
N Y Name of subsystem.
REQUEST_ID Variable Length
String
N Y The ID that uniquely identifies the request within the
CIMS system. It has the format:
<team>_<period><target>_<requestName><requestInst
ance>_<primeTeam>
REQUEST_TITLE Variable Length
String
Y Y Title of the request.
BEGIN_TIME Time N Y The start time of a request.
END_TIME Time N Y The end time of a request.
SEQUENCE String of Length
32
N Y Sequence name string.
POINTING_AGREEMENT Variable array of
Strings of length
80.
Y N Spacecraft agreements that were made during the
science planning process.
PRIMARY_POINTING String of Length
32
Y Y Primary pointing requirement for this request.
SECONDARY_POINTING String of Length
32
Y Y Secondary pointing requirement for this request.
CASSINI_SP_REQU
EST
REQ_DESCRIPTION Variable array of
Strings of length
80.
Y N Request description.
REQUEST_ID Variable Length
String
N Y The request id of the request associated with the
observation specified in the OBSERVATION_ID field.
OBSERVATION_ID Variable Length
String
N Y The observation id of the observation associated with
the request specified in the REQUEST_ID field.
CASSINI_SP_REQ_
OBS
SEQUENCE String of Length
32
N Y Sequence name string.
SUBSYSTEM String of Length
32
N Y Name of subsystem.
OBSERVATION_ID Variable Length
String
N Y An EK unique internal identifier that is made up of a
sequence and a number concatenated together.
OBSERVATION_TITLE Variable Length
String
Y Y Observation title.
CASSINI_ENB_OBS
ERVATION
SEQUENCE String of Length N Y Sequence name string.
 
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TABLE COLUMNS TYPE NULLS
OK
INDEXED DESCRIPTION
32
OBS_AS_FLOWN_NOTES Variable array of
Strings of length
80.
Y N Information about the execution of the observation
onboard the spacecraft
(E.g., name of as-flown PEF, indication of change in
execution from what was planned, problems with the
execution, brief results)
SUBSYSTEM String of Length
32
N Y Name of subsystem.
REQUEST_ID Variable Length
String
N Y The ID that uniquely identifies the request within the
CIMS system. It has the format:
<team>_<period><target>_<requestName><requestInst
ance>_<primeTeam>
REQUEST_TITLE Variable Length
String
Y Y Request title.
SEQUENCE String of Length
32
N Y Sequence name string.
CASSINI_ENB_REQ
UEST
REQ_AS_FLOWN_NOTES Variable array of
Strings of length
80.
Y N Information about the execution of the request onboard
the spacecraft
(e.g., name of as-flown PEF, indication of change in
execution from what was planned, problems with the
execution, brief results)
REQUEST_ID Variable Length
String
N Y The request id of the request associated with the
observation specified in the OBSERVATION_ID field.
OBSERVATION_ID Variable Length
String
N Y The observation id of the observation associated with
the request specified in the REQUEST_ID field.
CASSINI_ENB_REQ
_OBS
SEQUENCE String of Length
32
N Y Sequence name string.
 
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4.2. Data Format and Definition
Please see:
Multimission Software Interface Specification (SIS) SPICE Events Kernel,
 NAIF
Document No. 371, Version 1.0,