1 / 23

Space Plug-and-Play Architecture (SPA) and SSM

Space Plug-and-Play Architecture (SPA) and SSM. Introduction. SPA implements a self-configuration Publish/Subscribe methodology Computer-negotiated interfaces permit the elements of a complex system to interoperate without the need of traditional interface control documents

nola
Download Presentation

Space Plug-and-Play Architecture (SPA) and SSM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Space Plug-and-Play Architecture (SPA) and SSM

  2. Introduction • SPA implements a self-configuration Publish/Subscribe methodology • Computer-negotiated interfaces permit the elements of a complex system to interoperate without the need of traditional interface control documents • SPA processing sequence: • Network discovery and configuration • Component registration (Publish) • Component queries • Component subscriptions (Subscribe)

  3. Introduction • Accelerates the development and integration process by reducing or eliminating error-prone human interpretation • Standards based • SPA standards submitted to AIAA • Provides a contract between component providers that if their component is SPA compliant they can expect full interoperability on a SPA system

  4. Software Architecture SPA Applications Non-SPA Applications SPA API SPA Middleware Core Libraries Core Services Subnet Management Platform Abstraction Library Libraries Operating System and System Services • Board Support Package

  5. Software Architecture • SPA Middleware • Software required in order to support SPA infrastructure and functionality • Open source SPA middleware reference implementation provided by AFRL - SPA Services Manager (SSM) • SSM Target Architectures • VxWorks 6.x using Real Time Processes (RTPs), Linux 2.6.x, and Windows XP and 7 • Design uses a Platform Abstraction Layer (PAL) to ease port to other platforms

  6. Software Architecture • SPA Middleware Core Services • Discovery and addressing service • Network topology discovery, component discovery, and component addressing methodology • Publication service • Component registration, re-registration, deregistration • Query service • Query methodology in order to identify components that provide required data consumption and/or functionality • Subscription service • Methodology to subscribe and unsubscribe to required data and/or functionality

  7. Software Architecture • SPA Middleware Core Services cont. • System status monitoring service • Methodology to monitor overall SPA system status and provide appropriate response to SPA system anomalies • SPA Middleware Core Libraries • A Collection of commonly used SPA functions, constants, classes, utilities, etc that provide basic functionality to perform several SPA tasks • Dynamically or statically linkable

  8. Software Architecture • SPA Middleware Subnet Management • Subnet management for multiple heterogeneous subnets. For example, SpaceWire (SM-S), USB (SM-U), I2C (SM-1), etc. • Provides interoperability between different types of SPA subnets

  9. Example SPA System • SPA Network • SPA Processor Resource • SPA Core Component • SPA Application • SPA Router • SPA-S Device • SPA-U Device • SPA-1 Device SPA PR3 SPA PR1 LS SPA PR2 A3 SM-S SM-S A3 A4 CAS SM-L SM-L A2 A1 SM-S SM-L SM-S SM-U SM-1 R1 R2 R3

  10. Software Architecture OSI Model SPA Model Application Data, application-to-application communication Applications & Devices Transport End-to-end connection and reliability SPA Messaging Interface Network Path determination and logical addressing SPA Subnet Managers Data Link Physical addressing SPA-X Protocols SPA-S, SPA-U, etc Physical Media, signal and binary transmission I2C, USB, SpaceWire, Sockets

  11. Software Architecture • Platform Abstraction Library • Abstracts OS and architecture differences • Threading, semaphores, file I/O, timing, XML parsing, etc • Code modifications needed to port to a specific OS should only happen inside this platform specific library • SPA Application Programming Interface (API) • Defines a standard programming interface which allows a software application to interoperate with other software applications or devices • Could be used to abstract different PnP middleware implantations

  12. SPA Services Manager

  13. Computer-negotiated Interfaces • Extended Transducer Electronic Data Sheet (xTEDS) • Contains a complete interface description of a SPA component • Component-specific service request • Component-specific service request replies • Commands • Data messages • eXtensible Markup Language (XML) based • Schema controlled

  14. Common Data Dictionary • A universal dictionary of terms, names, definitions, qualifiers, units, scales, formats, interfaces, etc. • Available as a standard reference • A living document

  15. AppliquéSensor Interface Module (ASIM) • Provides SPA interface to a legacy or simple device • Pre-programmed to support SPA messaging, xTEDS registration, and Subscription/Publishing. • SM-S (SpaceWire) ASIMs are currently available • SM_U (USB), SM-1 (I^2C), and SM-C (CAN) ASIMs are currently being developed

  16. Validation - Component Components to test as UUT • Use SPA Test Suite (SPATS) to validate SPA core components against Standards documents. • SPATS will test each component in isolation (the Unit-Under-Test or UUT), simulating the non-UUT components in a protocol exchange • Verifies protocols and message formats are followed • Hardware support required for SM-X and SPA Device SPATS testing • SPATS • Java GUI and core code • Suite of SpatsTests • Match SpatsTests to UUT Component Type • Each SpatsTest exercises set of protocols • SPATS verifies protocol content, sequence, and messages are correct SM-S ASIM / Component CAS SM-S SM-L SM-U ASIM / Component LS SM-U SPA Application SM-1 ASIM / Component SM-1 On System w IP With Hardware Support

  17. CubeFlow Tools • Creating SPA software can be more complicated than creating traditional software. • xTEDS – Not many people are used to handcrafting XML • ASIM – ASIM protocol is a different way of thinking about embedded software • PnP Flight Software using standard interface and data centric publish/subscribe paradigm • CubeFlow tools automate many common SPA software development requirements • Open source web based tool suite

  18. CubeFlow Tools • xTEDS Developer • Assists a user in creating and maintaining xTEDS through a UI without requiring full XML knowledge

  19. CubeFlow Tools • ASIM Wizard • Aids creation of ASIM code for supported platforms by generating the code templates that match the selected xTEDS

  20. CubeFlow Tools • App Wizard • Aids creation of SPA application templates that will utilize a given device kind, as specified through the selected xTEDS

  21. Common Data Dictionary Tool • Common Data Dictionary (CDD) Tool • Used to manage and define the Common Data Dictionary

  22. CubeFlow Training Courses & Development Kits • SDL and COSMIAC have developed a training course including hardware / software to introduce SPA concepts • Development kit contains all the items needed to develop xTEDs, ASIMs, and applications, and test their functionality

  23. CubeFlow Training Courses & Development Kits • As of Dec 2010 there are 343 registered users on the CubeFlow site • Over 500 individuals trained from 100+ organizations including: • NASA • Lockheed • Boeing • NRO • ORS • Universities

More Related