A Standard for Flight Dynamics Interfaces

1
A Standard for Flight Dynamics Interfaces

• Frank DregerESA
• ESOC, TOS-GFT

2
Overview

• Motivation
• Mission families
• Ground segment interfaces
• Interface survey
• Standardisation example
• Conclusion

3
Why standardise the external Flight Dynamics
Interfaces?

• Simplify interface definition/negotiation
• Reduce development effort
• Reduce validation effort
• Improve interface quality (robustness)
• Ease ground segment design

4
Mission Families

• Earth observation
• Observatories
• Interplanetary
• Science
• Geostationary LEOP
• Third party support

5
Interfaces to other Ground Segment Elements

• Ground stations
• Tracking/ranging data
• Predictions
• Mission Control System
• Telemetry structure definition
• Telemetry
• Command parameters
• Orbit event predictions
• Propagation delay prediction

6
Interfaces to other Ground Segment Elements

• (Scientific) users
• Reconstructed/predicted attitude
• Reconstructed/predicted orbit
• Operations requests (mission planning input)
• Industry (support team)
• Flight Dynamics database
• Orbit event predictions
• S/C performance parameters

7
Interface Survey, e.g. Command Parameters

• Different interface implementations for
• EURECA (1992-1993)
• ERS-1/2 (1994-today)
• CLUSTER-I/II (1996, 2000-today)
• XMM-Newton (1999-today)
• INTEGRAL (2002-today)
• Cryosat (planned for 2004)

8
Commonality Command Parameters

• Related to an activity (command sequence)
• Limited time validity
• A set of command parameters
• Value
• Identifier
• Description
• Representation
• calibrated (on-board)
• raw (engineering units)
• Auxiliary information (Sun angles, etc.)

9
Interface Users and Usage

• Initially
• Software to software
• Software to human
• Usually/eventually
• Both

10
Standardisation Example a vision

• Generic command parameter set interface
• Based on INTEGRAL/Cryosat (and others)
• Implemented in XML
• Validated via DTDs and XML schema
• Viewing, printing and web publishing via XSLT
• ICD generic ICD specific instances

11
Conclusion

• Standardisation of Flight Dynamics Interfaces
• is what we need to do
• must focus on the content
• may reduce cost
• will increase quality and robustness