Low Speed Multidrop Busses - New Architectures Enabled by All-Digital Low Speed Low Speed Multidrop Busses - New Sensor Networks Architectures Enabled by All-Digital Low Speed Gianluca Furano Sensor Networks

Outline Introduction Gianluca Furano Sensor Overview Star ESA/ESTEC - Data Systems Division Busses Sensor Bus Gains Activities at September 16, 2008 ESA

Conclusions

1 / 16 Low Speed Multidrop Busses - New Architectures 1 Enabled by Introduction All-Digital Low Speed Sensor 2 Networks Sensor Bus Overview

Gianluca The “Star” architecture Furano Where do we already use digital busses Outline The Transducer Bus Introduction What do we gain? Sensor Bus Overview Star 3 It is not just chat Busses Sensor Bus Gains Activities at 4 Conclusions ESA

Conclusions

2 / 16 On board transducer networks, part of a strategy.

Low Speed Multidrop Busses - New Architectures The needs. Enabled by All-Digital On board transducer networks are part of a long haul strategy Low Speed Sensor shared between ESA and the European industry, and which Networks aims for the development of efficient spacecraft architecture Gianluca Furano solutions.

Outline

Introduction What for. Sensor Bus Digital and mixed ASIC technology has allowed concentration Overview Star of functions that once were distributed on multiple PCBs on a Busses Sensor Bus single component. As a matter of fact size (and Gains RELIABILITY!) of SCUs is sometimes constrained by number Activities at ESA of connectors more than number of functions. Conclusions

3 / 16 Discrete sensors and discrete lines

Low Speed Multidrop Some numbers: Busses - New Architectures Discrete sensors seem to be unavoidable in all systems. Enabled by All-Digital Moreover, their number is growing, due to the growing Low Speed Sensor peripheral intelligence. But looking at their functions we Networks discover that most of them are only simple thermistors... Gianluca Furano

Outline

Introduction

Sensor Bus Overview Star Busses Sensor Bus Gains Activities at ESA

Conclusions

4 / 16 The Architecture

Low Speed Multidrop Busses - New Architectures Enabled by All-Digital Context Low Speed Sensor Networks In the context of spacecraft sub systems evolution and global

Gianluca spacecraft architecture efficiency strategy, there is an increasing Furano need for data networks.

Outline

Introduction What the future will bring

Sensor Bus Overview At esa we see future spacecrafts on board communications Star based on safe digital serial busses, bridged to allow Busses Sensor Bus interoperability Gains Activities at ESA

Conclusions

5 / 16 The Architecture (2)

Low Speed Multidrop Busses - New Architectures Enabled by All-Digital ESA’s strategy Low Speed Sensor Networks ESA has been developing a strategy towards the adoption by

Gianluca European space industry of a common standard for point to Furano point interfaces. Outline The concept of sensor network is a good candidate to Introduction transform discrete interfaces into bus ones, providing that a Sensor Bus proof of concept and an in depth analysis of the consequences Overview Star at system level due to the introduction of such technology in a Busses Sensor Bus spacecraft is done. Gains Activities at ESA

Conclusions

6 / 16 What do we have already

Low Speed Multidrop Busses - New Architectures Command & Control Enabled by All-Digital MIL-STD-1553 has been used for a decade now in European Low Speed Sensor spacecrafts. The amount of know how in European industry is Networks such that is easy to foresee still a long future for it Gianluca Furano CAN bus is getting momentum, since it overcomes many of

Outline the limitations of MIL-1553, allowing low power RTs, use of

Introduction cheap COTS EGSE, and solid development methods.

Sensor Bus Overview Star Fast Links Busses Sensor Bus Spacewire is already the workhorse for fast point to point Gains Activities at links. With the availability of the router and SpWRTC ASICs ESA may even get into C&C. Conclusions

7 / 16 How this is mapped in ECSS

Low Speed Multidrop ECSS-E50-09 (draft) Busses - New Architectures will sit on top of BOSCH CAN 2.0 specs narrowing them down Enabled by All-Digital for space use, and defining missing items. Low Speed Sensor Networks ECSS-E50-13 (in public review) Gianluca Furano will sit on top of MIL-STD-1553B reducing designer’s degrees

Outline of freedom, thus finally allowing interoperability.

Introduction Sensor Bus ECSS-E50-11/12 Overview Star Specify Spacewire and RMAP protocol Busses Sensor Bus Gains Activities at ECSS-E50-14 ESA Part A (published) has finally frozen the spec for the analog Conclusions point to point interfaces and “modern” TTC-B-01 interfaces. Part B will define the standard for low speed transducer bus 8 / 16 What do we need

Low Speed Multidrop Busses - New Architectures Enabled by All-Digital A low speed (∼ kbps) digital network with: Low Speed Sensor Networks 100s of addressable sensors on a single line Gianluca single Twisted Pair Furano ∼ 10m of branch length Outline

Introduction Self powering

Sensor Bus If the transducer IF is capable of self powering from the Overview Star data network this will allow to have single chip Busses Sensor Bus transducers, in nice SOT3 packages. Gains Activities at ESA

Conclusions

9 / 16 The Proposed Architecture

Low Speed Multidrop Busses - New Architectures A single chip intelligent transducer Enabled by All-Digital Low Speed Sensor Networks

Gianluca Furano

Outline

Introduction

Sensor Bus Overview Star Busses Sensor Bus Gains Activities at ESA

Conclusions

10 / 16 The possible gains

Low Speed Multidrop Busses - New Architectures Enabled by All-Digital Low Speed Sensor Networks In the context of spacecraft architecture optimisation, sensor Gianluca Furano networks are a good candidate for the optimisation of point to point interfaces, which are numerous: The vast majority of the Outline interfaces (98%) in a spacecraft are to simple sensors and Introduction actuators using analogue or discrete digital interfaces. Sensor Bus Overview Star Busses Sensor Bus Gains Activities at ESA

Conclusions

11 / 16 The possible gains (2)

Low Speed Multidrop Busses - New Architectures Enabled by All-Digital Low Speed By examining terrestrial developments in automotive, process Sensor control, and computing, it is possible to argue that sensor bus Networks

Gianluca technologies could offer significant benefits in terms of easier Furano system testing and integration, an increased potential for

Outline component re-use, and the possibility of sourcing components Introduction from different suppliers. Sensor Bus Sensor network concept has promising capabilities for space use, Overview Star with the ultimate objective of reducing the harness through a Busses Sensor Bus significant decrease of the amount of point to point interfaces. Gains Activities at ESA

Conclusions

12 / 16 But is not only to save some mass...

Low Speed Multidrop Busses - New Additional capabilities Architectures Enabled by All-Digital Standardization Low Speed Sensor Unique SW layer Networks Simpler acquisition architecture (“pull” instead of “push”) Gianluca Use of same set of sensors in flight and in AIT/V Furano Dramatic symplification of EGSE Outline Take away analog lines from the harness (solves EMI Introduction issues). Sensor Bus Industrial Edge Overview Star A big step towards complete platform reuse - Allows Busses Sensor Bus flexible dimensioning of the I/Os Gains Dynamic device discovery capability Activities at ESA Synergies with other powerful European domains like

Conclusions avionic and automotive

13 / 16 It is not just chat

Low Speed Multidrop Busses - New Activities at ESA Architectures Enabled by All-Digital Spin in from other domains Low Speed Sensor Test and characterization of I2C, 1-wire, LIN, SPI Networks Total dose test of COTS single chip sensors Gianluca A self contained temperature logger Furano Long term research Outline 2 TRPs ongoing for evaluation of digital sensor bus Introduction technology candidate Sensor Bus The idea is to Overview Star Avoid reinventing the wheel Busses Sensor Bus Start standardization (ECSS-E50-14B) ASAP Gains Activities at ESA RESULTS SOON! Conclusions

14 / 16 Summary and Conclusions

Low Speed Multidrop Busses - New Architectures Technology spin-in from other domains. Enabled by All-Digital Space may gain a lot from that Low Speed Sensor Slow (kbps) multidrop bus. Networks

Gianluca One single harness allows connection of 100s of Furano transducers/actuators of different type. Outline Dynamic network discovery capabilities (aka Plug’n Play). Introduction Data over power network (or power on data link) solution Sensor Bus Overview for simple units/SOC (like USB ). Star Busses Sensor Bus Simplifies software Gains Reduces harness Activities at ESA Increases reliability Conclusions

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