The Role of Software Agents in Space Operations

1
The Role of Software Agents in Space Operations

• Stuart D. Fowell
• SciSys Ltd, Clothier Road,Bristol, BS4 5SS, UK
• Tel. [phone]
• stuart.fowell_at_scisys.co.uk
• www.scisys.co.uk

2
Overview

• Key Issues
• Software Agents
• CORBA Agent Framework
• Demonstrators
• Future Directions
• Conclusions

3
Background Trends in satellite software

• Increasing diversity and complexity of missions
• Increased reliance with on board autonomy
• Increased use of ground automation
• Common software kernels (space and ground)
• Falling budgets (want more for less)
• Increased role of COTS, Re-use Open Source
• and a role for advanced Software Technologies

4
Key Issues

• Advanced software frameworks in satellite control
  systems allow
• Deployment of technologies that improve mission
  performance
• e.g. autonomous on-board scheduling of tasks
  without direct ground contact
• e.g. distributed station keeping for multi-sats
• Reduced costs
• reduces integration effort
• improves software quality
• enables increased software re-use between
  missions
• Built-in through a system of software agents
• Loosely-coupled components, that are distributed
  throughout the system
• Each function of the system implemented as a
  software agent
• e.g. attitude determination function
  auto-generated from MATLAB model

5
End-to-End Systems using Software Agents
Agent
6
End-to-End Systems using Software Agents
7
CORBA-based Software Agent Framework
8
SciSys microORB

• Minimum CORBA ORB
• ANSI C
• Supports Common Operating Systems
• Modular design
• Small memory footprint
• Static table-based memory allocation
• Supports TCP/IP and SCSP-TP
• Asynchronous Messaging Interface
• Collocation optimisations
• Naming and Trader Services
• Real-Time CORBA

Agent Framework
Agent Function
microORB
TCP/IP or SCPS-TP
9
Demonstrators

• Two practical demonstrations of use of Software
  Agent Framework
• RATE II
• Simple, Flight Demonstration of Attitude
  Determination
• fuzzy logic
• close integration with ground-based Operator GUI
• SOIF Testbed Demonstrator
• Complex, Ground Test-Bed of Spacecraft On Board
  Interface (SOIF)
• ground-based demonstration of AOCS distributed
  across network of flight computers

10
RATE II

• Joint experiment between Science Systems and SSTL
• Follow-on from aborted RATE experiment for
  QinetiQs STRV-1d
• Ground/Space Integration using Software Agent
  Framework
• Attitude Determination Remote Agent
• AD function implemented using Fuzzy Logic
• Remote Agent Framework
• SCOS O/S and microORB
• Attitude Determination MC MMI
• Graphic and tabular visualisation of UoSAT-12s
  attitude
• Toolbox of visual components
• Windows NT and commercial ORB
• To Fly on SSTLs UoSAT-12
• Exploits existing TCP/IP over Space Link
  capability

11
RATE II
UoSAT-12
SCOS
Control Centre
Windows NT
Agent MC MMI Framework
Agent Framework
Fuzzy Logic Att. Det.
Att. Det. MC MMI
microORB
CORBA ORB
TCP/IP
TCP/IP
12
RATE II
13
SOIF Testbed Demonstrator

• Joint experiment between Science Systems and
  University of Dundee
• Demonstration of AOCS distributed across network
  of flight computers within a spacecraft
• Extension to Attitude determination Using Agents
• Adds use of Agents, CORBA and SOIF to access
  other on-board systems
• TCP/IP over SpaceWire
• Test on UoDs SpaceWire Testbed
• Realistic on-board system, running over real
  spacecraft bus
• Provides benchmark performance

Space Systems Research Group
14
SOIF Testbed Demonstrator
Spacecraft
Flight Computer
Control Centre
TCP/IP
TCP/IP
Smart Instrument
Space Link Ethernet
Spacecraft Bus SpaceWire
15
SOIF Testbed Demonstrator

• Demonstration of all layers of SOIF Protocol
  Stack
• Acquisition of Sensor Data using SciSys prototype
  SOIF Command Data Acquisition Service
• SciSys microORB running over SciSys prototype
  SOIF Message Transfer Service
• UoDs TCP/IP over SpaceWire

16
Future Directions

• Space Agency evaluation studies
• British National Space Centre (BNSC) Advanced
  Technology programme
• ESA Leading Edge Technology programme
• NASA-GSFC
• OMG Space Domain Task Force
• SciSys are the BNSC representatives
• RFI2 CORBA-based Space Communications
• CCSDS Spacecraft Onboard Interfaces

17
Future Directions

• CCSDS Spacecraft Onboard Interfaces (SOIF)
• Standardise interfaces within a spacecraft
• SciSys are the BNSC representatives
• SciSys actively contributing to Messaging and
  Application Layers
• Prototyping SOIF Services through Demonstrators
• Provides rapid validation and/or feedback to SOIF
  panel

18
Conclusions

• Software agent framework
• Agent per function
• Loosely-coupled network of agents
• Abstract MC interfaces
• CORBA-based implementation
• Code-generation
• SciSys microORB
• Delivers
• Improved software quality
• Reduced integration effort
• Improved system management
• Increased re-use between missions