CSW data sheet for ITT - EMITS Invitation To Tender …emits.sso.esa.int/emits-doc/ASTRIUMLIM/GAIA_CSW/GAIA.ASF...Gaia Date : 7-December-2006 Ref : GAIA.ASF.TCN.CSW.00085 Issue : 1

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Ref : GAIA.ASF.TCN.CSW.00085 Issue : 1 Rev. : Date : 7-December-2006 Page : i

NbCars 19214 NbWords 3491 FileName CSW data sheet for ITT.doc

EADS/Astrium

Title

CCeennttrraall SSooffttwwaarree ((CCSSWW)) TTeecchhnniiccaall DDaattaa SShheeeett

CCII CCooddee:: 1144000000

Name and Function Date Signature

Prepared by

Verified by

Approved by

Authorized by

Application authorized by

Document type Nb WBS Keywords

TN CSW

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Ref : GAIA.ASF.TCN.CSW.00085 Issue : 1 Rev. : Date : 7-December-2006 Page : ii


EADS/Astrium

SUMMARY

This document provides a brief technical description of the Gaia Central Software (CSW).

Document controlled by: EADS ASTRIUM

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Ref : GAIA.ASF.TCN.CSW.00085 Issue : 1 Rev. : Date : 7-December-2006 Page : iii


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DOCUMENT CHANGE LOG

Issue/

Revision Date Modification Nb Modified pages Observations

1 7-Dec-06 All Original issue for CSW Components ITT.

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PAGE ISSUE RECORD Issue of this document comprises the following pages at the issue shown

Page Issue/ Rev.

Page Issue/ Rev.

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Page Issue/ Rev.

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TABLE OF CONTENTS

1 INTRODUCTION .............................................................................................................................................. 1

2 GLOSSARY ..........................................................................................................................................................2

3 SYSTEM CONTEXT ..........................................................................................................................................4

3.1 GAIA ON-BOARD SW ARCHITECTURE PRINCIPLES ............................................................................................................. 5 3.2 TARGET MACHINE .................................................................................................................................................................... 5

4 CENTRAL SOFTWARE (CSW) DESCRIPTION ............................................................................................6

4.1 OVERVIEW OF CSW LAYERED ARCHITECTURE.................................................................................................................... 6 4.2 CENTRAL SOFTWARE COMPONENTS NOT SUBMITTED TO ITT ......................................................................................... 7 4.3 CENTRAL SW COMPONENTS SUBMITTED TO ITT................................................................................................................ 9

4.3.1 General Description of CSW Applications ................................................................................................................................ 9 4.3.2 Application Breakdown Template............................................................................................................................................ 11 4.3.3 Application Dynamic Template ............................................................................................................................................... 13 4.3.4 Focus on “System” Software Component .................................................................................................................................. 14 4.3.5 Focus on “AOCS” Software Component................................................................................................................................. 16 4.3.6 Focus on “Platform” Software Component ............................................................................................................................... 17 4.3.7 Focus on “Payload” Software Component ................................................................................................................................ 17

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LIST OF FIGURES

Figure 1: Showing Central Software within Gaia Electrical Architecture ............................................................4

Figure 2: Gaia CDMU & EIU Block Diagram.........................................................................................................6

Figure 3: Central Software (CSW) Architecture .......................................................................................................7

Figure 4: PUS Implementation in Gaia DMS Software ..........................................................................................8

Figure 5: Central Software Component Architecture............................................................................................10

Figure 6: Application Breakdown Template through AOCS Sample .................................................................12

Figure 7: Application Dynamic Template ...............................................................................................................13

Figure 8: Spacecraft Modes & Transitions Diagram..............................................................................................14

Figure 9: System FDIR Levels ..................................................................................................................................15

Figure 10: AOCS Modes & Transitions Diagram..................................................................................................17

Figure 11: PLM Manager Interfaces.........................................................................................................................18

Figure 12: PLM Manager Modes & Transitions Diagram ....................................................................................18

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EADS/Astrium

1 INTRODUCTION

This document provides a brief technical description of the Gaia Central software (CSW).

The purpose of this document is to give basic knowledge of the Central Software architecture, and in particular of its applications:

• System and operability manager.

• Attitude & Orbit Control Software (AOCS).

• Platform manager (TT&C, power, TCS).

• Payload manager.

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2 GLOSSARY AOCS Attitude and Orbit Control System BAM Basic Angle Monitoring BC Bus Controller (MIL-STD-1553B bus) BIOS Basic Input/Output Software BM Bus Monitor (MIL-STD-1553B bus) BOL Beginning Of Life CDMU Control & Data Management Unit CDU Clock Distribution Unit (CDU in PLM) CPDU Command Pulse Distribution Unit (CPDU) CPS Combined Propulsion System CSW Central Software DHS Core Data Handling System Core (used in the context of "DHS Core" product reuse) DMS Data Management System = all data management services for Gaia DSA Deployable Sunshield Assembly EEPROM Electrically Erasable Programmable Read-Only Memory EIU Electrical Interface Unit E-SVM Electrical Service Module FDIR Failure Detection, Isolation and Recovery FOM Flight Operations Mode (spacecraft mode) FSS Fine Sun Sensor Gbit 109 bits Gibit 230 bits GOM Ground Operations Mode (spacecraft mode) HK HouseKeeping (telemetry data) ICB Internal Control Bus (within CDMU) IGM Inertial Guidance Mode (AOCS mode) INIT Spacecraft INITialisation mode (spacecraft mode) LAM Launch & initial Acquisition Mode (spacecraft mode) LGA Low Gain Antenna MDE Mirror Drive Electronics MMU Mass Memory Unit (within CDMU) MPS Micro-Propulsion System M-SVM Mechanical Service Module NCO Numerically Controlled Oscillator NM Normal Mode (AOCS mode) OBT On Board Time (in PLM CDU) OCM Orbit Control Mode (AOCS mode) OSE Optical Source Electronics PAA Phase Array Antenna

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PDEC Packet Telecommand Decoder PDHU Payload Data Handling Unit PLM Payload Module PM Processor Module PPS Pulse Per Second PROM Programmable Read-Only Memory PSK Phase Shift Keying PUS Packet Utilization Standard Red Redundant RAM Random Access Memory RM Reconfiguration Module RT Remote Terminal (MIL-STD-1553 bus) SAM Sun Acquisition Mode (AOCS mode) SBM Stand-By Mode (AOCS mode) SCET SpaceCraft Elapsed Time (time reference within SVM CDMU) SGM SafeGuard Memory SHP Standard High Power Command SKEL Spacecraft Key Event Log SOM Science Operations Mode (spacecraft mode) SpW SpaceWire link (ECSS-E-50-12A) SRAM Static RAM SREM Standard Radiation Environment Monitor SSC Separation Sequence Counter SSM Spacecraft Safe Mode (spacecraft mode) STR Star Tracker SUSW (CDMU) Start-Up Software TC Telecommand TFG Transfer Frame Generator TM Telemetry TSM Transition Mode TTC Telemetry, Tracking and Command TTR Telecommand, Telecommand & Reconfiguration UART Universal Asynchronous Receiver Transmitter VC Virtual Channel VPU Video Processing Unit

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Product Gaia Central Software (CSW)

3 SYSTEM CONTEXT

PayloadData HandlingUnit (PDHU)CDMU (nom)

Controller

Central SW architecture

Real Time OS(RTEMS)

BIOS(BSW)

I/O System

DHS Core

8 Gbit MMU

PLM 1553B

TCS

SVM 1553B

PCDU MPETRSPPAA GYROCDMU(red)

TC

Science TM (VC1)

PlaybackTM (VC2)

Real-Time TM (VC0)

SCET

SGM

RECONF

ASW Applications within Central SW

Basic SW delivered with CDMU:Start-Up SW, API SWBSW

STR

FSS

CPS

Science TM (VC3)

TM

CDU

System ManagerOperabilityDMS & Mass Memory MgrAOCSPlatform ManagerPayload Module Manager

PacketWire

BCSpW

HER Heritage

On-Board Control Procedures(OBCP)

OBCP On-Board Control Procedures(in SCL language)

TM Virtual Channel (VC)

EIU

Other Units than CDMUWith SW

PDHU SW

SW

STR SWTRSP SW

800 Gbit MM

VideoProcessor Units

(VPU)

VPU SW

MDE OSE

Units

SREM

Sync

Real-Time TM (VC4)

Figure 1: Showing Central Software within Gaia Electrical Architecture

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3.1 GAIA ON-BOARD SW ARCHITECTURE PRINCIPLES

The Gaia on-board software architecture relies on the following design principles: • Implement a central computer (CDMU) and software (CSW) covering the overall

spacecraft, Service Module (SVM), and Payload Module (PLM) command/control (C&C).

• Reuse SW and lessons learnt from experienced missions: this takes into account as major feature the capacity of reusing existing software and standards (e.g., Real-Time Operating System, Core Data Handling System with set of PUS Services), as well as taking benefits of positive feedback (autonomy functions, operability) from relevant missions (e.g., Rosetta / Mars Express / Aeolus / Herschel-Planck).

3.2 TARGET MACHINE

Refer to Figure 2: Gaia CDMU & EIU Block Diagram hereafter.

CPU • RISC processor items of the ESA’s SPARC family: ERC32 TSC695F implementing the SPARC V7, 20 MHz

MEM • 6 Mbyte SRAM for CSW execution on each CDMU Processor Module (PM). • 3 Mbyte EEPROM for non-volatile Central SW (CSW) image storage on each PM.

Time • Time: free-running (when CDU is not in the loop) + capacity of being synchronised by an external pulse received from PLM CDU. Smooth synchronisation algorithm within CSW. The time reference of the CDMU/CSW is the Spacecraft Elapsed Time (SCET) derived from the master oscillator of the CDMU.

MMU • 2 x 8 Gibit BOL Mass Memory Unit (MMU) with BER ≤ 10-14 within CDMU. Provides hardware-implemented mechanism for down-linking packet stores through VC2.

TC • TC @ 4 kbps, LVDS/NRZ-L signals

TM • TM @ 10 Mbps, LVDS/NRZ-L signals

VC • 5 TM Virtual Channels: VC0, VC1 (science), VC2, VC3 (science) and VC4. - 3 x 2 internal VC (VC0, VC2, VC4) @ 256 kbps; two real-time (VC0, VC4); one play-

back from CDMU MMU (VC2). - 2 x 2 external* VC (VC1, VC3) @ 10 Mbps; one Real-Time + one Play-Back; *

PacketWire links. Bus • 2 x dual-redundant MIL-STD-1553 buses:

- 1 dual-redundant MIL-STD-1553B bus for SVM - 1 dual-redundant MIL-STD-1553B bus for PLM

SpW • 2 x 2 SpaceWire links @ 10 Mbps - In flight: all links are connected from CDMU to EIU. - On ground: possibility to connect one of these SpW links to the SIF (CSW diagnostic

tool). Test • 2 x 1 RS422/UART serial links (used on ground only).

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Alarms

SyncFromCDU SHP

TimeReconfiguration Electronics

Alarm ConditioningSafeGuard Memory

SVM MIL-STD-1553B (external)

I/O 1

I/O n

…

I/O n

…

Internal Control Bus

TMX-Band10 Mbps

TCX-Band4 Kbps

TCX-Band4 Kbps

PLM MIL-STD-1553B (external)

I/OInterfaces

(A)

I/OInterfaces

(B)

SpaceWireLinks

UART

…

…

…

…

8 Gibit BOLMass Memory Unit

(A)

8 Gibit BOLMass Memory Unit

(B)

TC Decoder & CPDUTransfer FrameGenerator (TFG)

TC Decoder & CPDUTransfer FrameGenerator (TFG)

…

TMX-Band10 Mbps

I/O 1

TFGTime

Strobe

Inter-Processor Link for Service Mode

SpaceWireInterface (A)

ERC32 Processor

Module(A)

SpaceWireInterface (B)

ERC32 Processor

Module(B)

PPS

TM fromPDHU #A

(PacketWire)TM from

PDHU #B(PacketWire)

SpaceWireLinks

UART

TM fromPDHU #A(PacketWire)TM fromPDHU #B(PacketWire)

SHP

…CDMU

EIU

Figure 2: Gaia CDMU & EIU Block Diagram

4 CENTRAL SOFTWARE (CSW) DESCRIPTION

4.1 OVERVIEW OF CSW LAYERED ARCHITECTURE

The Central Software (CSW) is broken down into five (5) main components in a bottom-up approach as shown on

• RTEMS: the real-time operating system. • BIOS: a library of low-level services, without any task, for access to the hardware interfaces of

the CDMU. It is provided by the CDMU supplier in order to simplify the HW/SW integration on the CDMU.

• I/O System: this element implements all the Input/Output operations that are necessary at application level. It is dedicated to the operations that take place in the CDMU and on the buses and links that are connected to it. The detailed operations of equipment that is connected to these buses and links are implemented by the relevant application.

• DMS: implements the Packet Utilisation Services (PUS) and supports the applications.

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• Applications: these components implement the functional processing associated to the management of the spacecraft : Attitude and Orbit Control Software (AOCS), platform control, payload management and system management. They rely on the DMS for the PUS services and on the I/O System for Input/Output operations. The coupling between the different applications is kept as low as possible to ease parallel development.

Applications(AOCS, Bus, Payload, System)


RTOS

BIOS Core DHS PUS Library

IO System


Applications

(AOCS, Bus, Payload, System)

I/O S

yste

m

BIOS DMS (based on DHS Core)

Applications

(SYSTEM, AOCS, PLATFORM, PAYLOAD)

RTEMS

Figure 3: Central Software (CSW) Architecture

4.2 CENTRAL SOFTWARE COMPONENTS NOT SUBMITTED TO ITT

OS • Real-Time Operating System: RTEMS V4.6.1 version or later qualified version. The Real Time Executive for Multiprocessor Systems (RTEMS) is an Open Source COTS real-time operating system. It has been released into the public domain and ported on ERC32 with ESA support in 1995.

• The adaptation of the RTEMS software on ERC32 processor is available, but whenever the computer HW would require adaptation, corresponding information will be provided as part of the Basic SW from the computer H/W supplier.

BIOS • The BIOS (inherited from CDMU Basic Software) is a low-level software that allows encapsulating the access to the core computer hardware functions for the applications.

• The BIOS does not have any active process in order to give entire control of the dynamic aspects to the applications. The same principle is applied for FDIR where the BIOS only performs detection of failures but does not perform any isolation or recovery action which are taken at application level.

DMS • The DMS software based on the DHS Core is an ANSI-C library of data handling services for the support of PUS applications, independent from the specific HW aspects. It is organized as a catalogue of SW components starting from the documentation up to the

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Product Gaia Central Software (CSW) tests.

• The DHS Core has been designed for reuse and to provide a solution for implementing the PUS concepts, which can be quite memory and CPU consuming. It has been based on experience and lessons learned from PUS projects like Rosetta, Mars Express, Venus Express and was developed for TerraSAR-X and Pléiades on top of RTEMS in 2003 and according to the latest ECSS-E70-41A PUS version (PUS 2003).

• The DMS provides some architectural services, e.g. for communications between applications based on TC, TM and event software buses, and the PUS services as listed in the table below. In addition, the CDHS allows implementing and connecting, on top of its general packet handling services, all the other PUS services that are linked to the HW or private services specific to an application.

PUS service Comments Reuse CSW

#1 – TC verification TC acknowledgement: acceptance & execution

Full X

#2 – Device command distribution

Direct access to on-board devices New X

#3 – Housekeeping and diagnostic data reporting

Periodic HK & diagnostic TM Full X

#5 – Event reporting Events, Spacecraft Key Event Log (SKEL)

Adapted

X

#6 – Memory management Memory load, dump, check New X

#8 – Function management N/A

#9 – Time management Spacecraft Elapsed Time (SCET) update, Time Report

New X

#11 – On-board operations scheduling

Mission Time-Line Adapted

X

#12 – On-board Monitoring Full X

#13 – Large Data Transfer Ground to space uplink New X

#14 – Packet forwarding control

X-band TM transmission control Full X

#15 – On-board TM storage & retrieval

Control of spacecraft TM storage and playback into/from CDMU MMU

Adapt X

#17 – Test Ping Full X

#18 – On-board operations procedure

On Board Control Procedures Full X

#19 – Event-Action SW FDIR: reactions to events Full X

Figure 4: PUS Implementation in Gaia DMS Software

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The Gaia DMS is designed for minimizing the coupling between applications. That is the reason why the data and their related processing have been separated: the DMS library provides the code/algorithms for the PUS services and this processing is made and configured by tables provided by each application process independently through a register mechanism.

In addition to this dynamic initialisation, the DMS is also configured at compilation time by several parameters like:

• The PUS mission parameters defined in annex B of the ECSS document such as the TC/TM packets checksum type, the maximum number of monitoring, the minimum diagnostic interval.

• The sizing parameters for the TC/TM data flows such as the size of the routing queues, or the sizes and numbers of packets of each type that can be processed by the ASW.

4.3 CENTRAL SW COMPONENTS SUBMITTED TO ITT

4.3.1 General Description of CSW Applications

The Figure 5: Central Software Component Architecture shows a more detailed architectural breakdown of the Central Software (CSW). The applications that are submitted to the CSW Components ITT are:

1. system & operability manager 2. AOCS 3. platform control 4. payload manager

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CSW Components submitted to ITTCSW Components submitted to ITT

DMS

PLM MgrPLM_FW

Platform MgrAOCSSystem & Operability

EVENT_MGRPUS #5

MEM_LIBTIME_LIB QUEUE_LIBRING_LIB

ACT_LIB MATH_LIBTRIGO_LIB

CYC_MGR

LIBC

TC_LIBHK_TMPUS #3

TC_MGRPUS #1 TMBW_MGREVT_BUS PARAM_DBTM_BUS

TRAF_MGRPUS #16

MON_MGRPUS #12

TC_BUS

SLLS_LIBCHKSUM ERR_LIBDTM_MGRPUS #15

OBCP_MGRPUS #18

TESTPUS #17

MTL_MGRPUS #11

FCT_MGRPUS #8

ACT_MGRPUS #19

SYS_FW

IO SystemPM_CPLR

REAL-TIMETM_CPLR

PLAY-BACKTMD_CPLR

TC_CPLR

TC_CPLR

MMU_CPLR

1553 CONTEXT

INIT

TC_SEQ

SC_MODE-MGR

SpW

SUN ACQMODE

AOCS MGR

INERTIALGUID MODE

GYROFSS STR

THRUSTERµTHRUST

GUIDANCELAWS

GYRO-STELLARESTIMATOR CONTROLLERS

AOCS_FW

POWER_CTL

SVM_MGR

RF_MGR

PCDU

TRSPPAA

THERMAL_CTL

SVM_FW

PLM_MGR

VPUPDHU

VPU_MGRPDHU_MGR

BasicInput

OutputSystem(BIOS)

RTEMS Operating System

AUTO_SEQ

SAFEMODE

RS422

TCS_IO

NORMALMODE

ORBIT CTRLMODE

LASERCTL

MIRRORCTL

LASER(OSE)

MIRROR(MDE)

SREM

TRANSITIONMODE

EIU

EARTHEPHEMERIS

BUS_MGR

RTC_MGR

CDU_CPLR

ASTRO-STELLARESTIMATOR

DEV_MGRPUS #2

MEM_MGRPUS #6

TIME_MGRPUS #9

LDT_MGRPUS #13

RTM_MGRPUS #14

GOM LAM FOM SOM

FILEMGR

SKEL

TIME& SYNC TM TC

DEATHREPORT

RFDU

Figure 5: Central Software Component Architecture

CSW Application Contents System Manager & Operability Spacecraft mode manager (see Modes Diagram below)

Spacecraft initialization Launcher separation sequence Deployable Sunshield Assembly deployment sequence Spacecraft safe mode Flight operations mode (cruise and trajectory control, commissioning) Science operations mode (coupled operations with Payload Module, science at L2) Context manager (Safeguard Memory) Time and synchronization manager Spacecraft Key Event Log Death Report System FDIR: hierarchical, 5 levels of FDIR up to Last Chance configuration TM manager and TC manager File manager (CDMU MMU)

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CSW Application Contents AOCS AOCS mode manager (see Modes Diagram below)

Stand-By Mode Sun Acquisition Mode Inertial Guidance Mode Orbit Control Mode Transition Mode Normal Mode Guidance laws; Earth ephemeris (for PAA) Gyro-stellar estimator Astro-stellar estimator Controllers AOCS-Payload Module (PLM) interface control AOCS-Phased Array Assembly (PAA) interface control AOCS Monitoring/FDIR For each AOCS/CPS/MPS unit:

- AOCS Equipment Function (FCT) - AOCS Equipment Software Resource (SWR) - AOCS Hardware Abstraction Libraries (HAL)

CSW Application Contents Platform Manager Thermal control & monitoring software application (TCS)

Power management software application & pyrotechnics/NEA device management TT&C subsystem management application For each TT&C and power unit:

- Equipment Function (FCT) - Equipment Software Resource (SWR) - Hardware Abstraction Libraries (HAL)

CSW Application Contents Payload Manager Interface management with PLM:

- Management of PLM units: Payload Data Handling Unit (PDHU), Video Processing Unit (VPU), Mirror Drive Electronics (MDE), Optical Source Electornics (OSE), Clock Distribution Unit (CDU)

- Mirror, laser source controls - ESA Space Radiation Environment Monitor (SREM) data acquisition

4.3.2 Application Breakdown Template Each application is typically structured in the same way with five layers:

• The mode manager layer: contains the mode manager objects, in charge of modes and sub-modes transitions management, processing scheduling and FDIR management. For complex applications, such as System and AOCS, there is one mode manager object for each mode (in charge of managing the sub-modes of that mode) and a top-level mode manager (in charge of managing the application mode).

• The processing layer gathers all control laws processing used for the application completion. The “Set of processing” object is in charge of these processing scheduling and monitoring the functional behaviour.

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Equipment AHAL

Equipent AFunction

Mode BManager

ApplicationManager

Equipment BHAL

Equipent BFunction

Guidance

Star Tracker Function Gyro Function

Star Tracker SWR Gyro SWR

Inertial Attitude

Estimation

NMControl

NMManager

OCMManager

AOCS Manager

SBMManager

SAMManager

Equipment BHAL

Equipent BFunction

Sun Sensor Function

Sun Sensor SWR

GuidanceThrusterController Guidance

Equipent AFunction

Guidance

Application Manager

Mode Managers

Sets of processings

Equipment unit functions,

SWR and HAL

Guidance law

Equipment AHAL

Equipment BHAL

Star Tracker HAL Gyro HALEquipment B

HALSun Sensor

HAL

Figure 6: Application Breakdown Template through AOCS Sample

• The equipment function (FCT) layer is in charge, for each kind of unit, of defining

interfaces to be used by the “set of processing”, the mode manager objects. These are functional interfaces hiding the details of the Gaia SVM and PLM equipment units management from the “set of processing” objects. The FCT layer is also in charge of the selection of the equipment units that are effectively used. It also provides interfaces for ground or mode manager layer, to configure the equipment (switch them on/off) or reconfigure in case of failure detection. For that, the FCT implements a part of FDIR that is the recovery actions to be performed for a kind of equipment.

• The equipment software resource (SWR) layer is in charge of the commanding and monitoring of individual equipment units. It is also in charge of converting raw data into physical data according to the equipment unit characteristics. These physical data are made available to equipment FCT objects through dedicated interfaces.

• The equipment Hardware Abstraction layer is in charge of HW interface with the equipment through the HW interface layer of the DMS. It enables/disables the acquisitions / commands and determines the validity of acquired data. It defines the equipment

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Product Gaia Central Software (CSW) configuration procedures (on/off switching). Raw data is made available to the equipment SW resource objects through dedicated interfaces.

The good health of the equipment is performed at unit SWR level and the monitoring of functional behaviour is performed at equipment ORB level and set of processing level. But the decision of the recovery action to be performed is centralised on mode management level in order to manage the priority between the different requests and priority between requests of the same type in cases of simultaneous failures.

4.3.3 Application Dynamic Template A dynamic template is defined for each application of the Central Software (CSW). It is defined by the

following rules and illustrated in the Figure 7: Application Dynamic Template below: • One cyclic task performs TC reading, dispatching and execution, control processing, cyclic

TM generation inside the application. • One or several asynchronous tasks that perform long activities “subcontracted” by the cyclic

task, either in terms of CPU usage or in terms of overall duration for blocking activities such as unit configuration sequences (sequences of commands separated by delays).

• The asynchronous tasks are only activated by the cyclic task. When necessary, the asynchronous tasks are monitored by the cyclic task. When the cyclic task detects that an asynchronous task has not succeeded to complete its processing, it triggers an FDIR event.

Figure 7: Application Dynamic Template

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4.3.4 Focus on “System” Software Component

Spacecraft Modes

The Gaia Central Software (CSW) “System” component provides a spacecraft mode manager that implements and controls the modes shown on Figure 8: Spacecraft Modes & Transitions Diagram below:

• Spacecraft Initialisation Mode (INIT) • Ground Operations Mode (GOM) • Launch & initial Acquisition Mode (LAM) • Spacecraft Safe Mode (SSM) • Flight Operations Mode (FOM) • Science Operations Mode (SOM)

ON

OFFOFFOFFOFF

S/C INITIALISATION S/C INITIALISATION MODE (INIT)MODE (INIT)S/C INITIALISATION S/C INITIALISATION MODE (INIT)MODE (INIT)

LAUNCH LAUNCH & INITIAL & INITIAL ACQUISITION ACQUISITION MODE (LAM)MODE (LAM)

LAUNCH LAUNCH & INITIAL & INITIAL ACQUISITION ACQUISITION MODE (LAM)MODE (LAM)

OFF[C0] / A0

MODE* = « GOM » [C1]/A1TC[C2]/A2 (UMBILICAL)

TC [C12]/A12FLIGHT OPERATIONSFLIGHT OPERATIONSMODEMODE (FOM)(FOM)

TC « SWITCH TO SAFE

MODE FROM GROUND »

[C17]/A17

CDMU PROCESSOR RESET orSWITCHOVER [C16]/A16

ERRORS/FAILURES [C14],A14

LOCAL RECOVERY & BACK [C15],A15

SCIENCE OPERATIONSSCIENCE OPERATIONSMODEMODE (SOM)(SOM)

FDIRFDIR

TC [C6]/A6

GROUND OPERATIONSGROUND OPERATIONSMODE (GOM)MODE (GOM)

GROUND OPERATIONSGROUND OPERATIONSMODE (GOM)MODE (GOM)

SPACECRAFT SAFESPACECRAFT SAFEMODE (SSM)MODE (SSM)

SPACECRAFT SAFESPACECRAFT SAFEMODE (SSM)MODE (SSM)

MODE* = INTO SGM EEPROM, TO DISTINGUISH BETWEEN GOM, LAM and SSM

UMBIL.=REMOVED [C3]/A3TC [C4]/A4

MODE* = « OTHERS » [C10]/A10TC[C11]/A11 (UMBILICAL)

MODE* = « LAM » [C8]/A8TC[C9]/A9 (UMBILICAL)

SBMSBM

SBMSBM SBM, SAMSBM, SAM

AOCS MODEAOCS MODE

TC [C5]/A5

TC [C7]/A7

SAMSAM

TSM, NMTSM, NM

IGM, OCMIGM, OCM

SYSTEM ALARMS(HARDWARE)

« SPURIOUS LAM »

Figure 8: Spacecraft Modes & Transitions Diagram

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Product Gaia Central Software (CSW) FDIR The Failure Detection, Isolation and Recovery (FDIR) function is not considered as a

unique separate object. Specified, SW-implemented, FDIR mechanisms are periodically executed (e.g., AOCS, power, TT&C, PLM surveillances) or asynchronously triggered (e.g., via Event or Parameter monitoring) within each post-launch modes and can lead either (i) to continue in the same mode or (ii) to enter the Safe Mode (FDIR levels 2 to 4, and Last Chance level). In other words, the FDIR takes the form of mechanisms distributed to every operational modes and centralised backup mode (Safe Mode). These mechanisms can be enabled or disabled depending upon the mode in which the spacecraft operates. When enabled, their triggering upon fault occurrence can lead either to FDIR Level 1 reconfiguration (same spacecraft mode continues to execute) or the FDIR Level 2 to 5 triggering (Safe Mode).

Groundcommands

Unf

ores

een

even

t

Level1

OK

OK

OK

OK

NOK

NO

K

NOK

NO

K

Processor reset& redundant units

Redundantprocessor & units

Reset PM, backto nominal units

Last chanceconfigurati on

Science continued

Missioninterrupted

On boardMission Time LineSpacecrafttelemetry

Gro

und

stat

ion

pas

s

Nominal autonomy Nominal autonomyAutonomous hierarchical FDIR

Gro

und

stat

ion

pas

s

Gro

und

stat

ion

pas

s

Localreconfigurat ion

Level2

Level3

Level4

Figure 9: System FDIR Levels

Auto

Sequences The CSW “System” component also provides autonomous operational functions for:

• The sequence following the separation from the launcher: from Launch Pad until Earth Acquisition with automatic restart in case of failure leading to computer reset of processor switchover.

• The sequence performing the Combined Propulsion System (CPS) priming: firing pyro valves for initial pressurisation of the propulsion with automatic restart in case of failure leading to computer reset of processor switchover.

• The sequence performing the deployment of the Deployable Sunshield Assembly (DSA) deployment and the heating of the deployment mechanism.

• The TC reception time-out monitoring and the TC link recovery, including reconfiguration of transponder and RF switches.

• The TM maintenance, including reconfiguration of transponder and RF switches.

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EADS/Astrium

Product Gaia Central Software (CSW) CDMU MMU

& File Manager

A memory and file manager is implemented using the CDMU Mass Memory Unit (MMU): • MMU management. • Concurrent reads and write. • Create/copy/delete files. • File attributes (file type, file protection) modification • Defective memory areas management; file report

TC SEQUENCER

A TC Sequencer (TCSEQ) is provided to support operations: • 1 TC/sec; optional delays: 1-sec resolution • Loadable from CDMU MMU • Programmed as a sequence of commands executed at relative execution times • A TC Sequence can be executed as part of the spacecraft initialisation.

Context Memory

(SGM)

Context is managed through CDMU-provided SafeGuard Memory (RAM and EEPROM). • Protection through checksum of individual, functionally-consistent, SGM groups. • Default context management in case of SGM loss.

4.3.5 Focus on “AOCS” Software Component

AOCS Modes The “AOCS” component implements the following modes:

Sun Acquisition

Mode

Stand-By Mode

Normal Mode

Zoom

ASTRO

Gate ASTRO

Phase

Normal

ASTRO

CPS controlled

MPS controlled

Orbit Control Mode

Inertial Guidance

Mode

TranSition

Mode

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EADS/Astrium


Figure 10: AOCS Modes & Transitions Diagram

4.3.6 Focus on “Platform” Software Component

Platform The “platform manager” component provides the following functions: • Thermal Control Software:

- Table-driven temperature control. - Table-driven temperature monitoring.

• TT&C equipment manager – Transponder, Phased Array Antenna, RF switches: - Initialisation. - On-line supervision. - Reconfiguration procedures.

• Power equipment manager – PCDU: - PCDU TM reset - Selection of “PCDU controller in use” - Low battery voltage surveillance

4.3.7 Focus on “Payload” Software Component

Payload The “payload manager” component of the CSW interfaces with other components as shown on Figure 11: PLM Manager Interfaces below.

PLM MANAGER

VPU MANAGERPDHU MANAGER

CDU MANAGER

OSE MANAGER

MDE MANAGER

PAYLOAD application software

AOCS Application Software

System Application Software

IO System (1553 I/F)Core DHS

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EADS/Astrium


Figure 11: PLM Manager Interfaces

The “payload manager” implements and controls the PLM modes and transitions as shown on Figure 12: PLM Manager Modes & Transitions Diagram

OFF

INIT

ON

Run

Zoom+GateMode

GateMode

OperationalMode

[auto]

[AOCS]

[AOCS]

[AOCS]

[AOCS] or[SYSTEM]

or [TC]

[AOCS]/C1

TC or [SYSTEM]

[SYSTEM]

G2Oper

[AOCS]

Z+G2G

[auto]

Figure 12: PLM Manager Modes & Transitions Diagram

The “payload manager” provides equipment management for the PLM and some open loop controls:

• PLM units supervision and reconfiguration procedures. • Mirror drive control (open loop). • Laser source control (open loop).

Finally, the “payload manager” component SREM: - Data acquisition. - CCSDS packetisation. - Storage into CDMU MMU.

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EADS/Astrium

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Documents

CSW data sheet for ITT - EMITS Invitation To Tender …emits.sso.esa.int/emits-doc/ASTRIUMLIM/GAIA_CSW/GAIA.ASF...Gaia Date : 7-December-2006 Ref : GAIA.ASF.TCN.CSW.00085 Issue : 1