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Industrial Collaboration: Automotive Electronics Alberto Sangiovanni-Vincentelli
UC Berkeley Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 2 Automotive Collaborations General Motors (ASV)
Architecture Exploration Using Metropolis
FlexRay Scheduling
Cost Metrics
Toyota (K. Hedrick, E. Lee)
Cold Start Engine Controller
Pirelli (ASV)
Smart Tire
Daimler-Chrysler (all)
Embedded Software design
Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 3 ABS: Antilock Brake System
ACC: Adaptive Cruise Control
BCM: Body Control Module
DoD: Displacement On Demand
ECS: Electronics, Controls, and Software EGR: Exhaust Gas Recirculation.
GDI: Gas Direct Injection
OBD: Onboard Diagnostics
TCC: Torque Converter Clutch
PT: Powertrain Value from Electronics & Software More functions & features
Less hardware
Faster Potential inflection point. Now! Hybrid PT Electric Ignition ACC Rear Vision Passive Entry Side Airbags Fuel Cell Wheel Motor … OnStar OBD II
HI Spd Data Rear aud/vid CDs BCM ABS
TCC EGR Electric Fan
Head Airbags ... Electric Brake DoD GDI … … … … … … 1970s 1980s 1990s 2000s 2010s 2020s Electronics, Controls & Software is shifting the basis of competition in vehicles $1182 (+196%) 50 ECUs (+150%) 100M Lines of Code (+9900%) $400 20 ECUs 1M Lines ~ ~ Software $ Other $ Electronics $
Software $
Other $
Mechanical $ Mechanical $ Electronics $ AVG. AVG. Source: Matt Tsien, GM Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 4 Specification Analysis Development Process Buses Buses
Matlab CPUs Buses Operating
Systems Behavior Components Virtual Architectural Components C-Code IPs ASCET Metro: Separation of Concerns Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 5 Architecture Model: Abstraction Levels Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 6 Matching Models of Computation The functional and architectural models should be described using the same model of computation
Architecture Characteristics:
Network of processes connected by point-to-point FIFOs
Non-blocking reads and writes
Messages may be lost or duplicated within FIFO
Functional Model
Functional blocks operate concurrently
Single rate
No synchronization across processes
Non-blocking read, non-blocking write communication semantics
Mapping: intersection of behaviors
Before mapping, nondeterministic loss and/or duplication of messages in functional model
After mapping, functional loss/duplication follows architecture Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 7 Results With 2 send buffers:
No priority inversion
Average message latency = 4.165ms With 1 send buffer:
Priority inversion:
Message 7 < Message 1~6
2. Average message latency = 4.936ms Functional Model
14 functional processes
48 signals
CAN controller configurations:
Number of send buffers
Metric
Message End-to-end Latency Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 8 Automotive Collaborations General Motors (ASV)
Architecture Exploration Using Metropolis
FlexRay Scheduling
Cost Metrics
Toyota (K. Hedrick, E. Lee)
Cold Start Engine Controller
Pirelli (ASV)
Smart Tire
Daimler-Chrysler (all)
Embedded Software design
Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 9 Project Background and Motivation GM has decided to choose FlexRay as the future communication system
Importance of deciding the Communication Cycle Length, Slot Size and Slot Order in the FlexRay based system design.
There is currently no technique to determine these parameters for FlexRay.
Scheduling is currently done manually in GM, which is time consuming and error prone.
Need an incremental scheduling tool for FlexRay system which supports any form of automated bus/task schedule
Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 10 FlexRay Timing Hierarchy ACTION POINT OFFSET Source: FlexRay Specification 2.1 Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 11 FlexRay Message Passing Mechanism 1 2 3 4 5 6 7 ... 1 2 3 4 5 6 7 ... T1 T3 T4 s1 T2 s2 T5 @ FlexRay
Controller OSEK Kernel Middleware Application Software Host ECU 1 T1 T4 T2 @ FlexRay
Controller OSEK Kernel Middleware Application Software Host ECU 2 T3 T5 s1 s1 s2 s2 s1 s2 Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 12 Comparison for scheduling In Traditional Schedule:
Incremental changes
impossible without
full rescheduling
In Optimized Schedule:
A lot more porosity to
accommodate new
tasks and messages Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 13 Scheduling Tool Framework AETM - DB (XML) convert FlexRay communication
System design tool
Graphical Design Front End Internal Data Structure Scheduling
Engine AETM - DB1 (XML) Back-annotate Gant Graph Scheduling
Result Display Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 14 Automotive Collaborations General Motors (ASV)
Architecture Exploration Using Metropolis
FlexRay Scheduling
Cost Metrics
Toyota (K. Hedrick, E. Lee)
Cold Start Engine Controller
Pirelli (ASV)
Smart Tire
Daimler-Chrysler (all)
Embedded Software design
Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 15 Toyota: Coldstart Engine Controller Design (C. Zavala and K. Hedrick) Objectives:
Minimize the HC emissions of cold-start
Reduce design-to-implementation controller cycle time.
Challenges
Sensors not active, poor combustion, keep development cost low.
Strategies
Design of AFR and HC observers, use of design of automated tools, use of modern controller design techniques Experimental facilities Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 16 Transmission Control
Goal:
Improve drivability and fuel efficiency by automotive control.
Approach:
Utilize dynamical model-based analysis and controller design.
Control Strategy:
Multi-tiered approach to achieve shock-free gear shifting by smooth gear shifting control with engine/AT collaboration balancing between fuel economy & performance by optimal shift pattern scheduling Prospected control structure for intelligent shifting Smooth Gear Shifting Control Gas Pedal Brake Pedal Vehicle Speed Optimal Shift Pattern Scheduling Human Driver Model & Driving Conditions Identification Optimal Engine Torque Profile Optimal AT Friction Elements Torque Profiles Determine Driver’s Intentions &
Driving Condition in Real Time Chess Review, Nov. 21, 2005 "Automotive Electronics", ASV 17 Hybrid Systems Modeling Objectives
Hybrid System Analysis: study of a general semantics for simulator engines to execute hybrid system models.
Study of representations of discontinuities and interactions between continuous-time dynamics and simultaneous discrete events
The code generation project aims to produce application code automatically from graphical models in Ptolemy II If an outgoing guard is true upon entering a state, because of the triggering semantics of transitions, the time spent in that state is identically zero. This state is called a ¡° transient state ¡± .
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