Synthesis and Exploration of Multi- Level, Multi-Perspective - PowerPoint PPT Presentation

Synthesis and Exploration of Multi- Level, Multi-Perspective Architectures of Automotive Embedded Systems Jordan Ross , Alexandr Murashkin, Jia Hui Liang, Michał Antkiewicz, Krzysztof Czarnecki September 20 th , 2017 1

Background & Motivation Wants to design the power window Design Design Design E/E architecture Objectives Decisions Constraints With Respect To Creates E/E Synthesize Visualizes Architectural Model Candidate Candidates and with Variability Architectures Tradeoffs Emily Expresses Possible Candidate Architectures 2

Wants to design the power window Design Design Design E/E architecture Objectives Decisions Constraints With Respect To Creates E/E Synthesize Visualizes Architectural Model Candidate Candidates and with Variability Architectures Tradeoffs Emily Expresses Possible Candidate Architectures 3

Our Reference Model for Early Design System Perspectives Feature Model Warranty Parts Cost Variability Parts Cost Multi-Layer Latency … Functional Analysis Architecture Mass Hardware Design Architecture Device Node Classification Power Topology Communication Topology Multi-Perspective 4

Capturing Variability System Feature Presence Feature Model Function Presence Function Connector Function Implementation Presence Functional Analysis Architecture Choice Function Deployment Function Connector Hardware Design Architecture Deployment Device Node Type Device Node Presence Device Node Classification Power Connector Source and Target Topology Connector Presence Communication Topology Bus Type Connector Presence Connector Endpoints 5

Emily’s Power Window Example Driver PW Basic Up Express DriverWinSysFAA Down HW/SW HW localWinReq SW winCmd HW winReq WinSwitch WinArbiter WinControl WinMotor Express Down Express Up Feature Model Legend HW current CurrentSensor Feature Optional PinchDetectionFAA Mandatory SW HW object position Exclusive Features PositionSensor PinchDetection 6

Capturing Latency System • Form timing chains using functions and function connectors • Assign latencies to functional devices and Feature Model analysis functions • Assign message sizes to function connectors • Functional Analysis Architecture Deployed to smart node affects function latency • Deployed to hardware connector affects Hardware Design Architecture function connector latency Device Node Classification Power • Assign speed factors to smart nodes Topology • Different communication connectors have Communication Topology different transfer rates. 7

Capturing Mass, Parts Cost, and Warranty Parts Cost RQ1: What aspects of our reference model are unique and not found System Mass in current meta-models for E/E architecture? Or are found but not • Assign lengths to hardware connectors supported by reasoning? • Multiplicative factor for unit length mass for each connector type. Feature Model • Assign mass to device nodes. Cost Functional Analysis Architecture • Multiplicative factor for unit length cost for each connector type. • Assign cost to device nodes. Hardware Design Architecture Device Node Classification Warranty Cost Power • Assign replacement cost to device nodes. Topology Communication Topology • Assign failure rate in PPM 8

Wants to design the power window Design Design Design E/E architecture Objectives Decisions Constraints With Respect To Creates E/E Synthesize Visualizes Architectural Model Candidate Candidates and with Variability Architectures Tradeoffs Emily Expresses Possible Candidate Architectures 9

Some Example Design Exploration Scenarios 1. Emily would like to investigate the possibility of adding a dedicated ECU to each door (we call the door module). Precisely, she would like to find out if it is a cost effective solution while meeting the requirements for mass and latency. 2. Emily is tasked with designing the power window for a higher end car in which cost is irrelevant but mass should be minimized , she would like to explore the possible designs. Additionally, since it’s a high end car, all features should be included. Lastly, the end-to-end latency for pinch detection to react and reverse the motor should be less than 200 ms. 3. Emily would like to minimize the cost, regardless of the features to support an “economy class” vehicle her company is rolling out. Is there an optimal car design that does include all features? 10

What Design Decisions Can We Make? System 1. Feature “ ExpressUp ” is in the architecture. Feature Model 2. “ WinArbiter ” function is implemented in hardware. Variability 3. The “Switch” device node is smart Functional Analysis Architecture 4. The “ DoorModule ” device node is present in the architecture Hardware Design Architecture 5. The “ winCmd ” function connector uses Device Node Classification the “ localDoorBus ” bus connector to Power communicate. Topology Communication Topology …. Combine the system model with variability 11

What Design Constraints and Objectives Can We Have? System Feature Model 1. The end to end latency Warranty Parts Cost for the timing chain from the “ WinSwitch ” Parts Cost Latency Functional Analysis Architecture Mass function to the “ WinMotor ” function is Hardware Design Architecture less than 500 ms. 2. Minimize the total mass Device Node Classification Power of the system Topology … Communication Topology Combine the system model with quality perspectives 12

Generalizing the Possible Specifications 13

Example RQ2: Are there design exploration scenarios in which considering our reference model we can consider while others can not? Emily is tasked with designing the power window for a higher end car in which cost is irrelevant but mass should be minimized, she would like to explore the possible designs. Additionally, since its a high end car, all features should be included. Lastly, the end-to-end latency for pinch detection to react and reverse the motor should be less than 200 ms. Feature “ ExpressUp ” is in the architecture AND The end-to-end latency for timing chain PinchDetection_TC must be less than 200 ms AND Minimize the total mass of the architecture 14

Wants to design the power window Design Design Design E/E architecture Objectives Decisions Constraints With Respect To Creates E/E Synthesize Visualizes Architectural Model Candidate Candidates and with Variability Architectures Tradeoffs Emily Expresses Possible Candidate Architectures 15

How Is This All Possible? Wants to design the power window E/E architecture Creates E/E Synthesize Visualizes Clafer Web Tools Architectural Model Candidate Candidates and with Variability Architectures Tradeoffs Chocosolver Emily 16

Visualizing Tradeoffs With Clafer Web Tools 17

Case Studies https://github.com/gsdlab/ClaferCaseStudies/tree/master/PlainClafer/Automotive/ BodyDomain 18

Power Window Feature Model Driver Power Passenger Power Window Window implies Basic Express Express Basic Up / Up / Down Down Down Down implies Express Up Express Up 19

Door Locks Feature Model Door Locks implies Remote Key Passive Key Basic Access Entry Lock Switch Outside Door Speed Smart Position Handle Sensor Lock Individual Central Lock Button Capacitive Lock Switch Switch Sensor Sensor 20

Model Sizes Single Door Power Two Door Power Central Door Locks Window Window Features 3 (2) 6 (4) 7 (6) Analysis Functions 3 (1) 6 (2) 3 (2) Functional Devices 4 (1) 9 (2) 33 (15) Deployment 64 4096 96 Configurations Function 6 (2) 7 (4) 33 (18) Connectors Device Nodes 6 (2) 10 (3) 21 (14) Discrete/Analog 13 (13) 18 (18) 34 (30) Connectors Bus Connectors 1 (1) 2 (1) 2 (1) Number of Variants 32 thousand > 959 million ~ 2 thousand 21

How Does Our Approach Compare? Dedicated door ECU RQ1 Answer: Features, variability at all layers, RQ1: What aspects of our reference model are unique and not found vs. no door ECU function implementation, discrete/analog in current meta-models for E/E architecture? Or are found but not connectors, and power topology supported by reasoning? Possible to implement express up feature Dumb vs. Smart High-end car Economy car Distributed vs. 22 Centralized

A Closer Look at the Economy Scenario • Emily would like to minimize the cost, regardless of the features to support an “economy class” vehicle her company is rolling out. Is there an optimal car design that does include all features? RQ2: Are there design exploration scenarios in which considering our reference model we can consider while others can not? RQ2 Answer: Yes! 23

Looking at the Chocosolvers Performance RQ4: Is it even feasible to ask the individual design decisions, constraints, and objectives shown earlier? RQ4 Answer: The majority are feasible however, there are issues in when trying to find all optimal solutions. 24

Looking at the Chocosolvers Performance RQ5: Is it feasible to ask the 6 design scenarios when considering the single and two door power window model? RQ5 Answer: It is feasible when considering the single door power window, however not for the two door case. 25