Rule Base Arbitration - Automotive Grade Linux

Rule Base ArbitrationProposal of policy managerfrom real productDENSO CORPORATIONAdvanced Driver Information Technology Corporation

Introduction Kenji Hosokawa HMI developer for IVI at Denso since 2005 Graphics developer at ADIT since 2017 Wayland/Weston, Video input, GPU driver, DRM/KMS, . Advanced Driver Information TechnologyEstablished in 2003Joint venture Denso and BoschProduce IVI Platform for both MCsOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.1 /13

Outline What is the Rule Base Arbitration Background Rule Base Arbitration Ex. Screen transition Spec. What can be defined as a rule The Advantage of Rule based arbitrator] Sample of basic rule definition Sample of Exception rule def Software structure Overview Rule-based arbitrator structure ScheduleOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.2 /13

What is the Rule Base Arbitration?When several information for driver (Content) needs to benotified at the same time, RBA decides which content isprioritized.NaviPhoneArbitrationWarningOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.3 /13

Background Issue of legacy technology:Complexity of S/W Limit of status transition and Matrix Contents are increased in every model. Huge effort is needed for spec change. Huge maintenance effort is needed due to existingspec is unclear.HMI Manager Displaying preferable information to suitable area(display, position) based on driver’s character,preference, status and driving scene. Flexible display arbitration for consolidated cockpit.RBAEffortNumber of contents Difficult to present by Status transition and Matrix Flexible arbitration logic is needed as base technology for realizingconsolidation cockpit and HMI Manager conceptOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.4 /13

Rule Base Arbitration Legacy technology： Transition matrix New technology : Rule base designAll behavior are defined in one matrixtable.Contents displaying policy are defined asabstracted rule and judge by RBA engine.Example: State transition design with tableExample: Rule based designNext requiredAContents ACurrent37x37 1369cells“Disappear Aand Display B”ADD AOnce A is added, all the relationships withother display contents should be considered【Problem】Contents BAddContents CRuleRBAEngineOnce C is added, only define the rule to apply to C【Expected effort】Many combination is increased forarbitration matrix, even if only one contentis added.- Increasing much effort.Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.Even if new content is added, no affect toother content because RBA engine judges thedisplay contents based on defined rule.- Saving effort5 /13

Rule Base Arbitration - Ex. Screen transition Spec. Conventional：State machineRule basedContents def.telephoneETCTbT・・・Proposal serviceArea def.High Prio.MultimediaAreaProposal AreaNavigationAudioVehicle info・・・Normal AreaLow Prio.Basic Rule・Higher priority wins between areas・Later wins inside the areaExceptional rules・TbT notification is not displayed while navigation isdisplayed・Low prio. contents is not displayed whiletelephone is displayed Difficult to add new contentDifficult to understand intension orbackground of specificationDifficult to define exceptional transition( such transition is described as remark)Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved. Easily add new contentsSimple descriptionEasy to understand background or reason ofspecification6 /13

Rule Base Arbitration -What can be defined as a rule - Basic Rules Area definition(arbitration order, Z-order)Arbitration policyContent- Priority, behavior of arbitration result(cancel, waiting) Models for state transition (TAB screen transition in meter) Constraint formula Exception behavior when losing in arbitration Exceptional Rules(Logical formula using status of are or contents)Logical operators: AND, OR, Implication, Compare, 、 and so on.e.g. Cancel only when losing to specific content (usually waiting). And more Arbitration of operation rightsAnimation definition when transitionPlease refer “Syntax definition”(which will be provided later) for more detailsOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.7 /13

Rule Base Arbitration-The Advantage of Rule based arbitrator For OEM Intention/background of spec. can be ruled as it is.- To prevent specs from becoming a dead letter- To keep simple and high maintainability Can confirm concrete behavior of spec. with simulator/actual hardware Specification can be evaluated comprehensively.For Supplier To avoid complex software implementation.Can reduce bugs by automatic code generation from spec. Can reduce validation cost because spec has validated by OEMNew PointConventionalRule basedExpected effectSpec. def.Manual creationAutomatic generation by toolRule def.Filling arbitration rulematrix tableConstrains formulaProduction qualitycan be assured inearly sample.Rule validationComprehensive manualtestingAutomatic test by toolReduce cost forvalidation/testProductSoftwareDepends on HMI-FWIndependent of HMI-FW, OSReduce cost fordevelopingOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.8 /13

Rule Base Arbitration - Sample of basic rule def. LayoutContentsViewContent TEL {loserType: GOOD LOSERallocatable: [MM AREA]State OUTGOING {priority: STANDARD VALUE}State INCOMING {priority: STANDARD VALUE}State LIST {priority: STANDARD VALUE}sizeReference:Centralsize}ViewContent ETC {loserType: GOOD LOSERallocatable: [MM AREA]State NORMAL {priority: STANDARD VALUE}sizeReference:Centralsize}ViewContent VR {loserType: GOOD LOSERallocatable: [MM AREA]State NORMAL {priority: STANDARD Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.Package Displays {Display ICDISP {description:“IC"sizeReference: DisplaySizeCompositeArea ICDISP Root {layout: FixedPositionLayout {PositionContainer {x: 0y: 0basePoint: LEFT TOPareaReference: BGarea}PositionContainer {x: 240y: 210basePoint: LEFT TOPareaReference: MM AREA}・・・・｝AreaArea MM AREA {description:"MM INTR"arbitrationPolicy: LAST COME FIRSTsizeReference: Centralsizevisibility: That-of Services・OprAdvisoryzorder: That-of Services・OprAdvisory}Area VEHICLE INTR {arbitrationPolicy: PRIORITY LAST COME FIRSTsizeReference: Centralsizevisibility: That-of MM AREAzorder: That-of MM AREA}9 /13

Rule Base Arbitration - Sample of Exception rule def.Screen transition specMM・Switch operation area(MM AREA)SwitchoperationNoYesMultimedia interruptHigh prio Gr.Prio basedLow prio Order basedVRIncomingDispHUDadjustConditions： Multimedia and Switch operation displayed on thesame area Switch operation contents displayed by Switchoperation Contents group with low and High prio defined inMultimedia interrupt area Contents group with low prio: New contentsoverwrites previous ones. Contents group with high prio: High prio contentsoverwrites low prio ones.Audio//MM AREA: New contents basically overwrites old ones. But only Switch operation contents can be displayed during TELcontents displayed.Constraint TEL with prio in MM AREA {runtime: true(Exists MM INTR prioH { x x.isActive() } AND For-All SW INTR { x !x.isActive() })- For-All MM INTR prioL { x !x.isVisible() }}Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.10 /13

Software structure – overview –OE specificRBA spec modelCreationArbitration onLogicAPIArbitrationcontrollerResultHook requestsLayout control/ Sound routingSoundManagerWindowManagerNeed to consider how to connect/combinewith existing Window/Sound Mgr of AGL.Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.11 /13

Software structure - Rule-based arbitrator structure Basic func. Decide which contents shows at which area Arbitrate contents according to request from apps and scene like power on/off,auto driving, ) Notify arbitration result to apps The result contains difference from last result Synchronized multiple notifications bring no screen flickering VehicleInfoApps ArbitrationmanagerWindowmanagerArbitrationFW Apps manager Oct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved.Arbitration manager：- Receive contents request and scene info.- Arbitrate contents and notify the resultto apps.- Notify start/end of arbitration tosynchronize with Window manager.Arbitration FW：Arbitrate contents according to rule def.Iarbitrator I/F：- Receive contents / scene request.- Manage registered appsIArbitrationResultListener I/F：- Receive arbitration resultIArbitrationControlListener I/F：- Receive start/end of arbitration12 /13

ScheduleOctNovAGL Event F2F@MonacoDenso activity SAT Review (F2F)DecJan ‘19FebMarF2F @ Hawaii CES @ LasVegasSAT Review (F2F) or presentation at AMM Gap Ana. btw AGL Policy Mgr. and RBA Consideration how to connect/combine withWindow/Sound Mgr.Spec Dev.(view andmodel)Implementation andTestUpstreamOct 4th, 2019 / Cockpit System Business Unit. DENSO COPORATION All Rights Reserved. 13 /13

Legacy technology：Transition matrix 【Problem】 Many combination is increased for arbitration matrix, even if only one content is added.- Increasing much effort. All behavior are defined in one matrix table. New techn