Space data and information transfer systems -- Attitude data messages

ISO 13541:2010 specifies two standard message formats for use in transferring spacecraft attitude information between space agencies: the attitude parameter message (APM) and the attitude ephemeris message (AEM). Such exchanges are used for: preflight planning for tracking or attitude estimation support; scheduling attitude and data processing support; carrying out attitude operations; performing attitude comparisons; carrying out attitude propagations and/or sensor predictions; and testing to initialize sub-system simulators (communications, power, etc.). ISO 13541:2010 includes sets of requirements and criteria that the message formats have been designed to meet. For exchanges where these requirements do not capture the needs of the participating agencies, another mechanism may be selected.

Systèmes de transfert des informations et données spatiales -- Messages de données d'attitude

General Information

Status
Replaced
Publication Date
09-Sep-2010
Withdrawal Date
09-Sep-2010
Current Stage
9599 - Withdrawal of International Standard
Completion Date
10-Sep-2010
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INTERNATIONAL ISO
STANDARD 13541
First edition
2010-09-15
Space data and information transfer
systems — Attitude data messages
Systèmes de transfert des informations et données spatiales —
Messages de données d'attitude
Reference number
ISO 13541:2010(E)
ISO 2010
---------------------- Page: 1 ----------------------
ISO 13541:2010(E)
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ii © ISO 2010 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 13541:2010(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies

(ISO member bodies). The work of preparing International Standards is normally carried out through ISO

technical committees. Each member body interested in a subject for which a technical committee has been

established has the right to be represented on that committee. International organizations, governmental and

non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the

International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards

adopted by the technical committees are circulated to the member bodies for voting. Publication as an

International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 13541 was prepared by the Consultative Committee for Space Data Systems (CCSDS) (as

CCSDS 504.0-B-1, May 2008) and was adopted (without modifications except those stated in Clause 2 of this

International Standard) by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee

SC 13, Space data and information transfer systems.
© ISO 2010 – All rights reserved iii
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INTERNATIONAL STANDARD ISO 13541:2010(E)
Space data and information transfer systems — Attitude data
messages
1 Scope

This International Standard specifies two standard message formats for use in transferring spacecraft attitude

information between space agencies: the attitude parameter message (APM) and the attitude ephemeris

message (AEM). Such exchanges are used for:
⎯ preflight planning for tracking or attitude estimation support;
⎯ scheduling attitude and data processing support;
⎯ carrying out attitude operations;
⎯ performing attitude comparisons;
⎯ carrying out attitude propagations and/or sensor predictions;
⎯ testing to initialize sub-system simulators (communications, power, etc.).

This International Standard includes sets of requirements and criteria that the message formats have been

designed to meet. For exchanges where these requirements do not capture the needs of the participating

agencies, another mechanism may be selected.

The scope and field of application are furthermore detailed in subclause 1.2 of the enclosed CCSDS

publication.
2 Requirements

Requirements are the technical recommendations made in the following publication (reproduced on the

following pages), which is adopted as an International Standard:
CCSDS 504.0-B-1, May 2008, Attitude data messages

For the purposes of international standardization, the modifications outlined below shall apply to the specific

clauses and paragraphs of publication CCSDS 504.0-B-1.
Pages i to v
This part is information which is relevant to the CCSDS publication only.
Page 1-3
Add the following information to the reference indicated:
[4] Document CCSDS 301.0-B-3, January 2002, is equivalent to ISO 11104:2003.
[7] Document CCSDS 502.0-B-1, September 2004, is equivalent to ISO 22644:2006.
© ISO 2010 – All rights reserved 1
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ISO 13541:2010(E)
3 Revision of publication CCSDS 504.0-B-1

It has been agreed with the Consultative Committee for Space Data Systems that Subcommittee

ISO/TC 20/SC 13 will be consulted in the event of any revision or amendment of publication

CCSDS 504.0-B-1. To this end, NASA will act as a liaison body between CCSDS and ISO.

2 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
Recommendation for Space Data System Standards
ATTITUDE DATA
MESSAGES
RECOMMENDED STANDARD
CCSDS 504.0-B-1
BLUE BOOK
May 2008
© ISO 2010 – All rights reserved 3
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ISO 13541:2010(E)
(blank page)
4 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
AUTHORITY
Issue: Recommended Standard, Issue 1
Date: May 2008
Location: Washington, DC, USA
This document has been approved for publication by the Management Council of the

Consultative Committee for Space Data Systems (CCSDS) and represents the consensus

technical agreement of the participating CCSDS Member Agencies. The procedure for

review and authorization of CCSDS Recommendations is detailed in the Procedures Manual

for the Consultative Committee for Space Data Systems (reference [E3]), and the record of

Agency participation in the authorization of this document can be obtained from the CCSDS

Secretariat at the address below.
This document is published and maintained by:
CCSDS Secretariat
Space Communications and Navigation Office, 7L70
Space Operations Mission Directorate
NASA Headquarters
Washington, DC 20546-0001, USA
CCSDS 504.0-B-1 Page i May 2008
© ISO 2010 – All rights reserved 5
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
STATEMENT OF INTENT

The Consultative Committee for Space Data Systems (CCSDS) is an organization officially

established by the management of its members. The Committee meets periodically to address

data systems problems that are common to all participants, and to formulate sound technical

solutions to these problems. Inasmuch as participation in the CCSDS is completely

voluntary, the results of Committee actions are termed Recommended Standards and are

not considered binding on any Agency.

This Recommended Standard is issued by, and represents the consensus of, the CCSDS

members. Endorsement of this Recommendation is entirely voluntary. Endorsement,
however, indicates the following understandings:

o Whenever a member establishes a CCSDS-related standard, this standard will be in

accord with the relevant Recommended Standard. Establishing such a standard
does not preclude other provisions which a member may develop.
o Whenever a member establishes a CCSDS-related standard, that member will
provide other CCSDS members with the following information:
-- The standard itself.
-- The anticipated date of initial operational capability.
-- The anticipated duration of operational service.

o Specific service arrangements shall be made via memoranda of agreement. Neither

this Recommended Standard nor any ensuing standard is a substitute for a
memorandum of agreement.

No later than five years from its date of issuance, this Recommended Standard will be

reviewed by the CCSDS to determine whether it should: (1) remain in effect without change;

(2) be changed to reflect the impact of new technologies, new requirements, or new

directions; or (3) be retired or canceled.

In those instances when a new version of a Recommended Standard is issued, existing

CCSDS-related member standards and implementations are not negated or deemed to be non-

CCSDS compatible. It is the responsibility of each member to determine when such

standards or implementations are to be modified. Each member is, however, strongly

encouraged to direct planning for its new standards and implementations towards the later

version of the Recommended Standard.
CCSDS 504.0-B-1 Page ii May 2008
6 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
FOREWORD

This document is a Recommended Standard for Attitude Data Messages (ADMs) and has

been prepared by the Consultative Committee for Space Data Systems (CCSDS). The set of

attitude data messages described in this Recommended Standard is the baseline concept for

attitude representation in data interchange applications that are cross-supported between

Agencies of the CCSDS.
This Recommended Standard establishes a common framework and provides a common

basis for the interchange of attitude data. It allows implementing organizations within each

Agency to proceed coherently with the development of compatible derived standards for the

flight and ground systems that are within their cognizance. Derived Agency standards may

implement only a subset of the optional features allowed by the Recommended Standard and

may incorporate features not addressed by this Recommended Standard.

Through the process of normal evolution, it is expected that expansion, deletion or

modification to this document may occur. This Recommended Standard is therefore subject

to CCSDS document management and change control procedures, as defined in the

Procedures Manual for the Consultative Committee for Space Data Systems. Current

versions of CCSDS documents are maintained at the CCSDS Web site:
http://www.ccsds.org/

Questions relating to the contents or status of this document should be addressed to the

CCSDS Secretariat at the address indicated on page i.
CCSDS 504.0-B-1 Page iii May 2008
© ISO 2010 – All rights reserved 7
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES

At time of publication, the active Member and Observer Agencies of the CCSDS were:

Member Agencies
– Agenzia Spaziale Italiana (ASI)/Italy.
– British National Space Centre (BNSC)/United Kingdom.
– Canadian Space Agency (CSA)/Canada.
– Centre National d’Etudes Spatiales (CNES)/France.
– Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)/Germany.
– European Space Agency (ESA)/Europe.
– Federal Space Agency (FSA)/Russian Federation.
– Instituto Nacional de Pesquisas Espaciais (INPE)/Brazil.
– Japan Aerospace Exploration Agency (JAXA)/Japan.
– National Aeronautics and Space Administration (NASA)/USA.
Observer Agencies
– Austrian Space Agency (ASA)/Austria.
– Belgian Federal Science Policy Office (BFSPO)/Belgium.
– Central Research Institute of Machine Building (TsNIIMash)/Russian Federation.
– Centro Tecnico Aeroespacial (CTA)/Brazil.
– Chinese Academy of Sciences (CAS)/China.
– Chinese Academy of Space Technology (CAST)/China.

– Commonwealth Scientific and Industrial Research Organization (CSIRO)/Australia.

– Danish National Space Center (DNSC)/Denmark.
– European Organization for the Exploitation of Meteorological Satellites
(EUMETSAT)/Europe.
– European Telecommunications Satellite Organization (EUTELSAT)/Europe.
– Hellenic National Space Committee (HNSC)/Greece.
– Indian Space Research Organization (ISRO)/India.
– Institute of Space Research (IKI)/Russian Federation.
– KFKI Research Institute for Particle & Nuclear Physics (KFKI)/Hungary.
– Korea Aerospace Research Institute (KARI)/Korea.
– MIKOMTEK: CSIR (CSIR)/Republic of South Africa.
– Ministry of Communications (MOC)/Israel.
– National Institute of Information and Communications Technology (NICT)/Japan.
– National Oceanic and Atmospheric Administration (NOAA)/USA.
– National Space Organization (NSPO)/Chinese Taipei.
– Naval Center for Space Technology (NCST)/USA.
– Space and Upper Atmosphere Research Commission (SUPARCO)/Pakistan.
– Swedish Space Corporation (SSC)/Sweden.
– United States Geological Survey (USGS)/USA.
CCSDS 504.0-B-1 Page iv May 2008
8 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
DOCUMENT CONTROL
Document Title Date Status
CCSDS Attitude Data Messages, May 2008 Current issue.
504.0-B-1 Recommended Standard, Issue 1
CCSDS 504.0-B-1 Page v May 2008
© ISO 2010 – All rights reserved 9
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
CONTENTS
Section Page

1 INTRODUCTION......................................................................................................1-1

1.1 PURPOSE...........................................................................................................1-1

1.2 SCOPE AND APPLICABILITY.........................................................................1-1

1.3 CONVENTIONS AND DEFINITIONS ..............................................................1-2

1.4 STRUCTURE OF THIS DOCUMENT ...............................................................1-2

1.5 REFERENCES....................................................................................................1-3

2 OVERVIEW...............................................................................................................2-1

2.1 ATTITUDE DATA MESSAGE TYPES .............................................................2-1

2.2 ATTITUDE PARAMETER MESSAGE (APM)..................................................2-1

2.3 ATTITUDE EPHEMERIS MESSAGE (AEM) ...................................................2-2

2.4 EXCHANGE OF MULTIPLE MESSAGES........................................................2-2

2.5 DEFINITIONS....................................................................................................2-2

3 ATTITUDE PARAMETER MESSAGE (APM).......................................................3-1

3.1 OVERVIEW .......................................................................................................3-1

3.2 APM CONTENT.................................................................................................3-1

3.3 APM EXAMPLES ............................................................................................3-10

4 ATTITUDE EPHEMERIS MESSAGE (AEM) ........................................................4-1

4.1 OVERVIEW .......................................................................................................4-1

4.2 AEM CONTENT ................................................................................................4-1

4.3 AEM EXAMPLE ..............................................................................................4-12

5 ADM SYNTAX...........................................................................................................5-1

5.1 INTRODUCTION...............................................................................................5-1

5.2 LINES.................................................................................................................5-1

5.3 KEYWORDS......................................................................................................5-1

5.4 VALUES.............................................................................................................5-2

5.5 UNITS ................................................................................................................5-4

5.6 COMMENTS......................................................................................................5-4

6 SECURITY.................................................................................................................6-1

6.1 INTRODUCTION...............................................................................................6-1

CCSDS 504.0-B-1 Page vi May 2008
10 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
CONTENTS (continued)
Section Page
6.2 SECURITY CONCERNS WITH RESPECT TO THIS RECOMMENDED

STANDARD .......................................................................................................6-1

6.3 POTENTIAL THREATS AND ATTACK SCENARIOS ....................................6-2

6.4 CONSEQUENCES OF NOT APPLYING STATED SECURITY TO THE

TECHNOLOGY..................................................................................................6-2

6.5 DATA SECURITY IMPLEMENTATION SPECIFICS.......................................6-2

ANNEX A VALUES FOR SELECTED KEYWORDS (NORMATIVE) ..................A-1
ANNEX B RATIONALE FOR ATTITUDE DATA MESSAGES

(INFORMATIVE) ...................................................................................... B-1

ANNEX C ITEMS FOR AN INTERFACE CONTROL DOCUMENT

(INFORMATIVE) ......................................................................................C-1

ANNEX D ABBREVIATIONS AND ACRONYMS (INFORMATIVE) ...................D-1
ANNEX E INFORMATIVE REFERENCES (INFORMATIVE).............................. E-1
Figure Page

3-1 APM File Example Using Comments to Denote Updates ........................................3-10

3-2 APM File Example Using Frame of Another Spacecraft..........................................3-11

3-3 APM File Example Describing Sensor Frame to Body Frame Transform.................3-11

3-4 APM File Example Describing Orientation of Instrument........................................3-12

3-5 APM File Example with Euler Angle Rates.............................................................3-12

3-6 APM File Example with Euler Angle Rates (Repeated Axis)...................................3-13

3-7 APM File Example with Mission Elapsed Time ......................................................3-14

3-8 APM File Example with Optional Euler Elements and One Maneuver.....................3-15

4-1 AEM Example.........................................................................................................4-12

4-2 AEM Spinner Example............................................................................................4-13

Table

3-1 APM Header .............................................................................................................3-2

3-2 APM Metadata ..........................................................................................................3-3

3-3 APM Data .................................................................................................................3-4

4-1 AEM File Layout Specifications................................................................................4-2

4-2 AEM Header .............................................................................................................4-3

4-3 AEM Metadata..........................................................................................................4-4

4-4 Types of Attitude Ephemeris Data Lines....................................................................4-8

B-1 Primary Requirements.............................................................................................. B-2

B-2 Heritage Requirements ............................................................................................. B-3

CCSDS 504.0-B-1 Page vii May 2008
© ISO 2010 – All rights reserved 11
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
CONTENTS (continued)
Table Page

B-3 Desirable Characteristics .......................................................................................... B-3

B-4 Applicability of the Criteria to Attitude Data Messages ............................................ B-4

B-5 Services Available with Attitude Data Messages ...................................................... B-4

C-1 Items Recommended for an ICD .............................................................................. C-1

CCSDS 504.0-B-1 Page viii May 2008
12 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
1 INTRODUCTION
1.1 PURPOSE

1.1.1 This Attitude Data Message (ADM) Recommended Standard specifies two standard

message formats for use in transferring spacecraft attitude information between space

agencies: the Attitude Parameter Message (APM) and the Attitude Ephemeris Message

(AEM). Such exchanges are used for:
– preflight planning for tracking or attitude estimation support;
– scheduling attitude and data processing support;
– carrying out attitude operations;
– performing attitude comparisons;
– carrying out attitude propagations and/or sensor predictions;
– testing to initialize sub-system simulators (communications, power, etc.).

1.1.2 This Recommended Standard includes sets of requirements and criteria that the

message formats have been designed to meet. For exchanges where these requirements do

not capture the needs of the participating agencies, another mechanism may be selected.

1.2 SCOPE AND APPLICABILITY

1.2.1 This document contains two attitude data messages designed for applications

involving data interchange in space data systems. The rationale behind the design of each

message is described in annex B and may help the application engineer to select a suitable

message. Definition of the attitude accuracy underlying a particular attitude message is

outside of the scope of this Recommended Standard and should be specified via Interface

Control Document (ICD) between data exchange participants. Applicability information

specific to each Attitude Data Message format appears in sections 3 and 4, as well as in

annex subsection B3.

1.2.2 This Recommended Standard is applicable only to the message format and content,

but not to its transmission. The transmission of the message between agencies is outside the

scope of this document and should be specified in an ICD or by following a CCSDS standard

on transmission.

1.2.3 Description of the message formats based on the use of the eXtensible Markup

Language (XML) will be available. An XML schema is defined by the CCSDS Recommended

Standard titled ‘XML Specification for Navigation Data Messages’ (reference [5]). Agencies

should specify, via ICD, the ASCII file format to be exchanged (Keyword Value Notation

[KVN] or XML).
CCSDS 504.0-B-1 Page 1-1 May 2008
© ISO 2010 – All rights reserved 13
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
1.3 CONVENTIONS AND DEFINITIONS
The following conventions apply throughout this Recommended Standard:
a) the words ‘shall’ and ‘must’ imply a binding and verifiable specification;
b) the word ‘should’ implies an optional, but desirable, specification;
c) the word ‘may’ implies an optional specification; and
d) the words ‘is’, ‘are’, and ‘will’ imply statements of fact.
1.4 STRUCTURE OF THIS DOCUMENT
1.4.1 Section 2 provides a brief overview of the CCSDS-recommended Attitude Data

Message types, the Attitude Parameter Message (APM) and Attitude Ephemeris Message

(AEM).
1.4.2 Section 3 provides details about the structure and content of the APM.
1.4.3 Section 4 provides details about the structure and content of the AEM.
1.4.4 Section 5 provides details regarding syntax of the APM and AEM messages.

1.4.5 Section 6 provides information regarding security concerns related to the access and

transmission of the Attitude Data Messages.

1.4.6 Annex B provides a list of approved values for selected keywords in the ADM

Metadata sections.

1.4.7 Annex B lists a set of requirements that were taken into consideration in the design of

the APM and AEM, along with tables and discussion regarding the applicability of the two

message types to various attitude estimation tasks and functions.

1.4.8 Annex C lists a number of items that should be covered in ICDs prior to exchanging

ADMs on a regular basis. There are several statements throughout the document that refer to

the desirability or necessity of such a document; this annex lists all the suggested ICD items

in a single place in the document.
1.4.9 Annex D is a list of abbreviations and acronyms applicable to the ADM.
1.4.10 Annex E is a list of informative references.
CCSDS 504.0-B-1 Page 1-2 May 2008
14 © ISO 2010 – All rights reserved
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
1.5 REFERENCES

The following documents contain provisions which, through reference in this text, constitute

provisions of this Recommended Standard. At the time of publication, the editions indicated

were valid. All documents are subject to revision, and users of this Recommended Standard

are encouraged to investigate the possibility of applying the most recent editions of the

documents indicated below. The CCSDS Secretariat maintains a register of currently valid

CCSDS Recommended Standards.

[1] Information Technology—8-Bit Single-Byte Coded Graphic Character Sets—Part 1:

Latin Alphabet No. 1. International Standard, ISO/IEC 8859-1:1998. Geneva: ISO,

1998.
[2] Spacewarn Bulletin. Greenbelt, MD, USA: WDC-SI.

[3] JPL Solar System Dynamics. Pasadena, CA, USA: JPL.

[4] Time Code Formats. Recommendation for Space Data System Standards, CCSDS
301.0-B-3. Blue Book. Issue 3. Washington, D.C.: CCSDS, January 2002.

[5] XML Specification for Navigation Data Messages. Draft Recommendation for Space

Data System Standards, CCSDS 505.0-R-1. Red Book. Issue 1. Washington, D.C.:
CCSDS, November 2005.

[6] IEEE Standard for Binary Floating-Point Arithmetic. IEEE Std 754-1985. New York:

IEEE, 1985.
[7] Orbit Data Messages. Recommendation for Space Data System Standards, CCSDS
502.0-B-1. Blue Book. Issue 1. Washington, D.C.: CCSDS, September 2004.
NOTE – A list of informative references can be found in annex E.
CCSDS 504.0-B-1 Page 1-3 May 2008
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ISO 13541:2010(E)
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ISO 13541:2010(E)
CCSDS RECOMMENDED STANDARD FOR ATTITUDE DATA MESSAGES
2 OVERVIEW
2.1 ATTITUDE DATA MESSAGE TYPES
2.1.1 Two CCSDS-recommended Attitude Data Messages (ADMs) are described in this

Recommended Standard: the Attitude Parameter Message (APM) and the Attitude Ephemeris

Message (AEM).

2.1.2 The recommended attitude data messages are ASCII text format. While binary-based

attitude data message formats are computer efficient and minimize overhead on

uplinked/downlinked data streams, there are ground-segment applications for which an

ASCII character-based message is more appropriate. For example, when files or data objects

are created using text editors or word processors, ASCII character-based attitude data format

representations are necessary. They are also useful in transferring text files between

heterogeneous computing systems, because the ASCII character set is nearly universally used

and is interpretable by all popular systems. In addition, direct human-readable downloads of

text files or objects to displays or printers are possible without preprocessing. The penalty

for this convenience is inefficiency.

2.1.3 As currently specified, an APM or AEM file is to represent attitude data for a single

vehicle. It is possible that the architecture may support multiple vehicles per file; this could

be considered in the future.
2.2 ATTITUDE PARAMETER MESSAGE (APM)

2.2.1 An APM specifies the attitude state of a single object at a specified epoch. This

message is suited to inter-agency exchanges that (1) involve automated interaction and/or

human interaction, and (2) do not require high-fidelity dynamic modeling (for high-fidelity

dynamic modeling, see 2.3, Attitude Ephemeris Message).

2.2.2 The APM requires the use of a propagation technique to determine the attitude state at

times different from the specified
...

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