ECSS E-70-41: Telemetry & Telecommand Packet Utilisation Mario Merri European Space Agency

Transcription

1 ECSS E-70-41: Telemetry & Telecommand Packet Utilisation Mario Merri European Space Agency OMG meeting Paris 1

2 Content PUS History and Background PUS context Presentation of the ECSS Standard for TM & TC Packet Utilisation (PUS) OMG meeting Paris 2

3 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 OMG meeting Paris 3

4 History and Status of PUS The Packet Utilisation Standard (PUS) Issue 1 has been published as an ESA standard (PSS ) 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) OMG meeting Paris 4

5 PUS in ECSS Document Tree Glossary of Terms ECSS-P-00 Policy ECSS-M-00 ECSS-M-00 Project Project Management Management ECSS-Q-00 ECSS-Q-00 Product Product Assurance Assurance ECSS-E-00 ECSS-E-00 Engineering Engineering Level 1 Project Breakdown Structure Quality Assurance Systems Project Organisation Dependability Electrical & Electronics Phasing & Planning Configuration Safety EEE Components Mechanical Software Level 2 Information & Documentation Cost & Schedule Integrated Logistic Support Materials Parts & Processes S/W Product Assurance Communications Ground Ground Systems Systems & Operations PUS ECSS-E-70-nn Level 3 OMG meeting Paris 5

6 COMMS The Hardware Level of Control SATELLITE DEVICE BUS 63$&( /,1. TM TC Remote Control of a Device CONTROL CENTER GROUND LINK OMG meeting Paris 6

7 COMMS The Process Level of Control SATELLITE DEVICE BUS Application BUS 63$&( /,1. TM TC Remote Control of an Application CONTROL CENTER GROUND LINK OMG meeting Paris 7

8 Needs of the Satellite Control Technique Hardware-Level Control TDM Telemetry Fixed-length TC Frames Process-Level Control "Message-like" interface: Bi-directional, asynchronous, error-free exchange of data Flexibility of data generation Flexibility of data content CCSDS TM & TC Packets OMG meeting Paris 8

9 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) OMG meeting Paris 9

10 The Communication Layer Uses the CCSDS Recommendations for packets TM & TC TELEMETRY SOURCE PACKET: Packet ID PACKET HEADER Packet Sequence Control PACKET DATA FIELD Packet Length Data Field Header Source Data Packet Error Control 2 octets 2 octets 2 octets Variable Variable Variable Optional Optional TELECOMMAND PACKET: Packet ID PACKET HEADER Packet Sequence Control PACKET DATA FIELD Packet Length Data Field Header Application Data Packet Error Control 2 octets Variable Variable 2 octets 2 octets 2 octets Optional Optional OMG meeting Paris 10

11 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 OMG meeting Paris 11

12 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 OMG meeting Paris 12

13 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 OMG meeting Paris 13

14 Packet Data Field Header Telecommand Packet Data Field Header Telemetry Packet Data Field Header OMG meeting Paris 14

15 PUS Standard Services 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 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 18 On-board Operations Procedure 19 Event/Action OMG meeting Paris 15

16 Example of PUS Tailoring for a Mission Service Type: Memory Management (6) Service Sub-Type: Dump Memory using Absolute Addresses - TC (6,5) OMG meeting Paris 16

17 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 OMG meeting Paris 17

18 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 byproducts 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 OMG meeting Paris 18