| Earth Observation Mission CFI Software Usage Guide for Object Oriented Software |

Earth Observation Mission CFI Software
Usage Guide for Object Oriented Software

Internal Code: | P/SUM/DMS/01/026-077
Project code | EO-MA-DMS-GS-027
Issue | 4.2
Date | 31/01/2011

| Name | Function | Signature
Prepared by: | Carlos Villanueva Muñoz | Project Engineer |
Checked by: | Juan José Borrego Bote | Project Manager |
Approved by: | José Antonio González Abeytua | Division Head |

# DOCUMENT INFORMATION

Contract Data | Classification
--- | ---
Contract Number: | 15583/01/NL/GS | Internal |
Public |
Contract Issuer: | ESA / ESTEC | Industry | X
Confidential |

External Distribution
Name | Organization | Copies

Electronic handling
Document generator: | Doxygen 1.7.1
Electronic file name: | eo-ma-dms-gs-0002-21

# Document Status Log

Issue | Change Description | Date | Approval
--- | --- | --- | ---
1.0 | New document | 27/03/09 |
4.1 | Second release | 07/05/10 |
4.2 | Third release | 31/01/11 |

# ACRONYMS, NOMENCLATURE AND TERMINOLOGY

## Acronyms

ANX | Ascending Node Crossing
CFI | Customer Furnished Item
CS | Coordinate System
DEM | Digital Elevation model
DRS | Data Relay Satellite
ESA | European Space Agency
ESTEC | European Space Technology and Research Centre
EOCFI | Earth Observation CFI software
OSF | Orbit Scenario File
OSV | Orbit State Vector
POF | Predicted Orbit File
RA | Right Ascension
ROF | Restituted Orbit File
SDF | Swath Definition File
STF | Swath Template File
SUM | Software User Manual

## Nomenclature

CFI | A group of CFI classes, and related software and documentation that will be distributed by ESA to the users as an independent unit
CFI Class | A single class within a CFI that can be called by the user
Library | A software library containing all the CFI classes included within a CFI plus the supporting functions used by those CFI functions (transparently to the user)

## Notes in Terminology

In order to keep compatibility with legacy CFI libraries, the Earth Observation Mission CFI Software makes use of terms that are linked with missions already or soon in the operational phase like the Earth Explorers. This may be reflected in the rest of the document when examples of Mission CFI Software usage are proposed or description of Mission Files is given.

# APPLICABLE AND REFERENCE DOCUMENTS

## Reference Documents

[MCD] | Earth Observation Mission CFI Software. Conventions Document. EO-MA-DMS-GS-0001. Issue 4.2 31/01/11.
[MSC] | Earth Observation Mission CFI Software. Mission Specific Customizations. EO-MA-DMS-GS-0018. Issue 4.2 31/01/11.
[GEN_SUM] | Earth Observation Mission CFI Software. General Software User Manual. EO-MA-DMS-GS-0017. Issue 4.2. 31/01/11.
[EE_COMMON_SUM] | Earth Observation Mission CFI Software. EE Common Software User Manual. EO-MA-DMS-GS-0003. Issue 4.2. 31/01/11.
[F_H_SUM] | Earth Observation Mission CFI Software. FileHandling Software User Manual. EO-MA-DMS-GS-0008. Issue 4.2. 31/01/11.
[D_H_SUM] | Earth Observation Mission CFI Software. DataHandling Software User Manual. EO-MA-DMS-GS-0007. Issue 4.2. 31/01/11.
[LIB_SUM] | Earth Observation Mission CFI Software. Lib Software User Manual. EO-MA-DMS-GS-0003. Issue 4.2. 31/01/11.
[ORBIT_SUM] | Earth Observation Mission CFI Software. Orbit Software User Manual. EO-MA-DMS-GS-0004. Issue 4.2. 31/01/11.
[POINT_SUM] | Earth Observation Mission CFI Software. Pointing Software User Manual. EO-MA-DMS-GS-0005. Issue 4.2. 31/01/11.
[VISIB_SUM] | Earth Observation Mission CFI Software. Visibility Software User Manual. EO-MA-DMS-GS-0006. Issue 4.2. 31/01/11.

# INTRODUCTION

The Earth Observation Mission CFI Software is a collection of software functions performing accurate computations of mission related parameters for Earth Observation missions. The functions are delivered as software libraries gathering functions that share similar functionalities:

- EECommon: Classes to provide general functionalities and the error handling for the other libraries.
- FileHandling: Software for reading and writing files in XML format.
- DataHandling: Software for reading and writing Earth Observation Mission files.
- Lib: Software for time transformations, coordinate transformations and other basic computations.
- Orbit: Software for computing orbit information.
- Pointing: Software for target calculations.
- Visibility: Software for swath generation and visibility computation.

The purpose of the current document is to give a quick explanation of the CFI functionality and usage strategies. Information about the CFI from a software point of view (installation, libraries dependencies, hardware and software requirements...), consult [GEN_SUM]. To get a detailed information about the classes and interfaces, see other SUMs

# EARTH OBSERVATION CFI SOFTWARE USAGE CASES

The usage cases of the CFI can be classified in the categories listed below. For every case there is a description of how to use the Earth Observation CFI (classes and methods to use, data flow, the calling sequence and examples). Besides the information provided in these sections, the Earth Observation CFI installation package contain a more detailed example program for each library (in JAVA or C++) that can be used for reference (see [GEN_SUM] for more info about the example program)

- Reading XML files
- Writing XML files
- Working with Earth Observation Mission files (reading, writting and validation)
- Time correlation initialisation
- Time operations
- On-Board Time calculations
- Using different astronomical models
- Coordinate transformations
- Orbit calculations
- Generation of Earth Observation Mission Files
- Target calculation:
  - Attitude computation.
  - Targets.
  - Targets crossing the atmosphere.
  - Targets with a Digital Elevation Model.
- Swath calculations

- Visibility calculation