ECSS E7041: Telemetry

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ECSS E-70-41 Telemetry Telecommand Packet
Utilisation

• Mario Merri
• European Space Agency

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Content

• PUS History and Background
• PUS context
• Presentation of the ECSS Standard for TM TC
  Packet Utilisation (PUS)

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What is the PUS?

• The PUS complements the CCSDS packet TM TC
  standards by defining the application-level
  interface between ground and space
• It covers nominal, contingency and
  troubleshooting operations for both AIV and
  mission operations
• It provides operational concepts and a set of
  on-board Services meeting them
• It defines TM TC packets (including structures)
  to exploit the on-board Services
• It promotes the selection and tailoring of the
  on-board Services according to the needs of a
  given mission
• It allows mission-specific extensions

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History and Status of PUS

• The Packet Utilisation Standard (PUS) Issue 1 has
  been published as an ESA standard (PSS-07-101) in
  May 1994
• At that time, in Europe, only the EURECA mission
  used packet TM TC
• Once established, the ECSS Working Group E-70 on
  Ground Systems and Operations had the mandate
  for the revision of the PUS to inject
  real-mission experience
• Revised PUS submitted for ECSS Steering Board
  approval at the end of 1999
• Currently in public review (closing date 1 June
  2001)

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PUS in ECSS Document Tree
ECSS-P-00 Policy
Glossary of Terms
ECSS-Q-00 Product Assurance
ECSS-M-00 Project Management
ECSS-E-00 Engineering
Level 1
Project Breakdown Structure
Systems
Quality Assurance
Dependability
Electrical Electronics
Project Organisation
Safety
Mechanical
Phasing Planning
Level 2
Configuration
Software
EEE Components
Information Documentation
Communications
Materials Parts Processes
Ground Systems Operations
Cost Schedule
S/W Product Assurance
Integrated Logistic Support
ECSS-E-70-nn
http//www.estec.esa.nl/ecss/
Level 3
PUS
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The Hardware Level of Control
TM
TC
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The Process Level of Control
TM
TC
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Needs of the Satellite Control Technique
TDM Telemetry Fixed-length TC Frames
Hardware-Level Control

• "Message-like" interface
• Bi-directional, asynchronous, error-free exchange
  of data
• Flexibility of data generation
• Flexibility of data content

Process-Level Control
CCSDS TM TC Packets
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How to use CCSDS Packets?

• There are many ways to use them!
• increased flexibility
• What needs to be defined is
• Which information they should contain
• What is the data exchange protocol
• How are data formatted/structured

TM TC Packet Utilisation Standard (PUS)
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The Communication Layer

• Uses the CCSDS Recommendations for packets TM TC

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Scope and Purpose of the PUS

• It is an Application Interface Document between
  Ground and Space
• It is applicable to all classes of mission
• Telecomms, Science, Earth Observation
• LEO, MEO, GEO, Deep Space
• etc.
• It allows cost and risk reduction for both space
  and ground segment

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Structure of the PUS

• Defines PUS operations concepts
• Specifies Packet Data Field Header
• Specifies a set of standard PUS Services based
  on
• Commonality needed by several missions
• Coherence self contained
• Implementation independent no assumption on
  on-board architecture
• Minimum set core functionality of a mission
  control system and electrical ground support
  equipment
• Specifies data field structure and parameter
  encoding
• Defines rules for "tailoring" the PUS for a
  mission

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PUS Operations Concepts

• Not all of the operation concepts are necessarily
  applicable to a given mission
• Operations concepts include
• Overall concepts and guidelines for application
  process and packet design
• Concepts relating to routine operations
  scenarios, such as telecommanding and telecommand
  verification, telemetry reporting, on-board
  software management, on-board operations
  scheduling, on-board monitoring, on-board storage
  and retrieval and packet transmission control
• Concepts that relate to non-routine operations
  scenarios, such as software and memory
  maintenance and troubleshooting, diagnostic data
  reporting and off-line testing

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Packet Data Field Header
Telecommand Packet Data Field Header
Telemetry Packet Data Field Header
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PUS Standard Services
11 On-board Operations Scheduling 12 On-board
Monitoring 13 Large Data Transfer 14 Packet
Transmission Control 15 On-board Storage and
Retrieval 16 On-board Traffic Management 17 Test 1
8 On-board Operations Procedure 19 Event/Action
1 Telecommand Verification 2 Device Command
Distribution 3 Housekeeping and Diagnostic Data
Reporting 4 Parameter Statistics
Reporting 5 Event Reporting 6 Memory
Management 7 Task Management 8 Function
Management 9 Time Management
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Example of PUS Tailoring for a Mission
Service Type Memory Management (6) Service
Sub-Type Dump Memory using Absolute Addresses -
TC (6,5)
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Mission Using or Planning to Use the PUS

• XMM
• Meteosat Second Generation (MSG)
• INTEGRAL
• GOMOS (Envisat Instrument)
• ATV (Automated Transfer Vehicle)
• Orsted (Danish microsatellite)

• PROBA
• ROSETTA
• MARS EXPRESS
• FIRST/PLANK
• CRYOSAT
• GOCE
• GALILEOSAT

Basically, all future ESA missions are planned to
adopt the PUS
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Conclusions

• The ESA PUS has been revised with "real-life"
  experience
• The new ECSS PUS will be soon available and
  should provide a solid baseline for the
  definition of telemetry and telecommand packets
  of new missions
• A number of tools are planned that will
  facilitate the tailoring of the PUS to mission
  and provide as by-products the automatic
  generation of mission-specific documentation and
  supporting telemetry and telecommand database
• This will further establish the PUS as "The
  Standard" in this field for cost and risk