Powertrain Control (1)/50

Anna G. Stefanopoulou, Powertrain Control Laboratory

University of Michiganannastef@umich.edu

National Science FoundationUS Department of Energy, ARPA-E,

US Army with

Bosch, Daimler, Ford, Toyota

Thanks to the

Engine Control At the Rugged Edge of

High Efficiency

IFAC- AACAdvances in Automotive Control, Kolmarden, June 2016

Powertrain Control (2)/50

1

2

4610

20

4060

100

200

400

1900 1920 1940 1960 1980 2000 2020 2040 2060

FUELECO

NOMY[m

pg]

YEAR

1921ModelT(CITYONLY) HybridsCarisetal.560010(ADJ) TCDiesel(GasolineEq.)AustinandHellman730790 TCGasolineEPAFETrends2013 FED.STDS.2017-2025

BASICCOMB.,(DESIGN,FUEL,OCTANE,CR)

EMISSIONS

CAFE– FE–CO2CATALYSTS

FED.STD.2017-2025

CITY/HWY(Unadjusted)3,750lb.TestWt.

G. Lavoie. "Reflections on the Evolution of Ideas and Technology in SI Engine Combustion" Oral Presentation - ICEF2014-5703. ASME 2014 Internal Combustion Engine Division Fall Technical Conference, October 19-22, 2014, Columbus, IN.

Light Duty Fuel Economy Trends Over the Last 100 Years

Powertrain Control (3)/50

History Lessons (US-focused)Slow ..? Slender … ?

Powertrain Control (4)/50

Slow ..?

No .., just better!

Slender … ?

Powertrain Control

12V BAS Micro-HEV

**

Cost effectiveness

TRBDS--1

GDIVVL

VVTFR

PHEV MPG

DIESEL

HEV

PHEV MPGeEV (estimated)

Data Sources: 1. Assessment of Fuel Economy Technologies for Light-Duty Vehicles (2011) National Research Council2. * www.fueleconomy.gov DOE & EPA website (MPGe : 1 Gallon of Gasoline = 33.7 kWh)3. **MPG baseline 2008 midsize cars. NHTSA stats (2014)

2025 Target

Powertrain Control

12V BAS Micro-HEV

**

Cost effectiveness

TRBDS--1

GDIVVL

VVTFR

DIESEL

HEV

Data Sources: 1. Assessment of Fuel Economy Technologies for Light-Duty Vehicles (2011) National Research Council2. * www.fueleconomy.gov DOE & EPA website (MPGe : 1 Gallon of Gasoline = 33.7 kWh)3. **MPG baseline 2008 midsize cars. NHTSA stats (2014)

2025 Target TWC

SCR+…$...$

Exhaust After-

Treatment

Powertrain Control (7)/50

Efficiency Improvement: Turbo-Downsizing (TRBDS)

270

270

400

600

300

255

255

BSFC 3.6L V6 [g/kWh]

Engine Speed [RPM]

270

270

300

600

400

300

FTP−75

Engin

e L

oad

[N

m]

1000 1500 2000 2500 3000 3500

50

100

150

200

250

300

350

0−5

−15−20

−10−5

−25

−5

0

Engine Speed [RPM]

rel. BSFC 2.0L I4 − 3.6L V6 [%]

−25−25

−5

−5

0

5

−10−5

10

−5

−10

−20−15

0

−15

FTP−75

Engin

e L

oad

[N

m]

1000 1500 2000 2500 3000 3500

50

100

150

200

250

300

350

20%

10%

5%

Efficiency Improvements %

Worst

Controlling the Dynamics

Original 3.6L V6

Turbocharged2.0L I4

5. Cnv4. v/eTC3. thr/wg2. TC-Dnsz1. Dnsz

Powertrain Control

12V BAS Micro-HEV

**

Cost effectiveness

TRBDS--2

TRBDS--1

GDIVVL

VVTFR

2025 Target

PHEV MPG

DIESEL

HEV

PHEV MPGeEV (estimated)

Powertrain Control (9)/50

9

Naturally Aspirated

TurbochargedTurbocharged+eEGR

Low-pressure Exhaust Gas

Recirculation (eEGR)

Technologies with Large Tradeoff between Fuel Efficiency & Transient Response

Turbo-Downsizing + Cooled Low Pressure EGR (TRBDS-2)

Powertrain Control

12V BAS Micro-HEV

**

Cost effectiveness

TRBDS--2

TRBDS--1

GDIVVL

VVTFR

2025 Target

PHEV MPG

DIESEL

HEV

PHEV MPGeEV (estimated)

?

Powertrain Control (11)/50

Homogeneous Charge Compression Ignition (HCCI)

Figure: Adopted from Edwards, D. in Dynamics Days, 2008, Knoxville, TN

Spark Ignition (Gasoline)• Spark ignites premixed fuel-air• Propagating flame

HCCI (Gasoline)• Spontaneous autoignition• Uniform combustion

Compression Ignition (Diesel)• Fuel injected into compressed air• Diffusion flame

SI HCCI CIPeak Temperature (K) >2000 1600 1800

NOx emission High Low MediumCombustion Duration (CAD) 40 2-10 40

Car Makers Seek New Spark In Gas Engines The Wall Street Journal 09/28/04“… engineers call homogenous-charge compression-ignition, or HCCI and expected to provide

80% of the efficiency of a hybrid or a diesel for 20% of the cost, …”

Too high pressure riserate at high Load

Powertrain Control (12)/50

Figure: Adopted from Edwards, D. in Dynamics Days, 2008, Knoxville, TN

Spark Ignition (Gasoline)• Spark ignites premixed fuel-air• Propagating flame

Auto-Ignition (HCCI-Gasoline)• Spontaneous autoignition• Uniform combustion

Compression Ignition (Diesel)• Fuel injected into compressed air• Diffusion flame

Fuel Injection

Gas

olin

e Diesel

Spark Ignition

Homogeneous Charge Compression Ignition (HCCI)

No DirectActuation

Controlled by Trapped Dilution

Powertrain Control (13)/50

Gasoline Systems - HCCIHCCI Actuators & Sensors (Cost)

VariableValve

Injector

In-cylinderpressure sensor

Controllerθ50ref

θ50

Combustion phasing controlled through

trapped dilutionAnd

mixture reactivity

Powertrain Control (14)/50

Homogeneous ChargeChemical Kinetics=Arrhenius Integral

-

Powertrain Control (15)/50

The importance of the Thermal Coupling

from Cycle-to-Cycle

Powertrain Control (16)/50

Stable, Unstable, and Limit Cycle Behavior

Automotive EngineeringSAE 2002-01-0111– LundRegions with Stable and Unstable operationASME ICE 2000– Caterpillar Limit cycle behaviorSAE 892068– Southwest Research InstituteVery Stable and Unstable behavior at different regions

Stability in auto-thermal reactors Heerden 1953, Liljenroth 1918

Breathing Combustion

Intake Temperature, Tivc (K)

Blow

Dow

nTe

mpe

ratu

re, T

bd(K

)

Early CombustionPhasing

Chiang, CDC 2004 Chiang, IEEE-TCST 2004

Powertrain Control (17)/50

Drive around Stable Points!Breathing Combustion

Intake Temperature, Tivc (K)

Early CombustionPhasing

Chiang CDC 2004 & Chiang, IEEE-TCST 2004

Clean or Efficient? An Engine Goes for ‘Both of the Above’

By LINDSAY BROOKEAugust 19, 2007

SAE-2009-01-1131

Powertrain Control (18)/50

Two Input Single Output (TISO) Controller

Powertrain Control (19)/50

TISO Controller & Load Governor

Powertrain Control (20)/50

Still a strange ringing

Powertrain Control (21)/50

The importance of the Chemical (Fuel) Couplingfrom Cycle-to-Cycle

Heat Release Analysis

Observations from the high variability operation

Detailed Heat Release Observations

Key factors for describing CVNonlinear coupling betweenØ the recycled thermal energyØ the recycled chemical energy in the unburned fuel

Powertrain Control (24)/50

Ø Period doubling bifurcations

Ø Thermal runaway

Ø Noisy simulations match the data

Model Predicts Global Behavior (2 nonlinear ODEs)

Powertrain Control (25)/50

E. Hellström, et al., Cyclic variability and dynamical instabilities in autoignitionengines with high residuals. IEEE Trans on Control Systems Technology, 2013.

Model Validation: Predict the onset of CV

Controlling Combustion at its Limit

InjectionTiming (usoi)

CombustionPhasing (θ50)

HCCI Control Toolbox~T

orqu

ePh

asin

g

Powertrain Control (28)/50

Controls Overview

[1]Jade,Dissertation,2014[2]Larimore,Dissertation,2014[3]Ravietal.,JDSMC,2012[4]Gorzelic,Dissertation,2015[5]Zhangetal.,DSCC,2014[6]Nuesch,Dissertation,2015

SI/HCCI switching controlsObjective: • Short• Torque• Low penalty

HCCI controls:Objective:• Torque

SI controls:Objectives:• Torque• Stoich. air-fuel ratiofuel

spark

throttle

fuel

valve timing

fuel

spark

throttle

2-stage cams

valve timing

SI/HCCI supervisory controlObjective: • Fuel economy• Emissions• Driveability

[1], [2], [3]

[4], [5]

StandardSwitch:

Yes or no?

Powertrain Control (29)/50

Mode TransitionsSignificant number of mode transitions during driving cycle!

During the 7-15 cycles of switching the efficiency is worst than SI.

Switch if you stay long enough in HCCI to pay for the switching penalty.

Powertrain Control (30)/50

0 500 1000 1500 0 500 0 5000

20

40

60

80

Velocity[m

ph]

Time [s]

FTP75 HWFET US06

Vehicle Model

City with cold start Highway Aggressive

0

10

20

30

Velocity[m

ph]

500

1000

1500

2000

2500

Enginespeed[R

PM]

0 5 10 15

0

50

100

150

Enginetorque[N

m]

Time [s]0 5 10 15

0

1

2

3

Fuelflow

[g/s]

Time [s]

Reference

Tolerance

Brake pedal

Clutch pedal

Gear

vAccel.

pedal

DriverRef. velocity

Ref. gear

Vehicle

Clutchtorque

Brake pedalClutch pedalGear

vAccel.pedal

DriverRef. velocity

Ref. gear

Clutch state

Vehicle

TireforcesDrive-

trainClutchtorque

Brake pedalClutch pedalGear

vTeAccel.pedal

DriverRef. velocity

Ref. gear

Clutch state

Vehicle

TireforcesDrive-

trainEngine

M

ωe

Clutchtorque

Brake pedalClutch pedal

Tcmd

Gearv

ECU

TeAccel.pedal

DriverRef. velocity

Ref. gear

Clutch state

Vehicle

TireforcesDrive-

trainEngineuphase / uswitch

M

ωe

0

10

20

30

Velocity[m

ph]

500

1000

1500

2000

2500

Enginespeed[R

PM]

0 5 10 15

0

50

100

150

Enginetorque[N

m]

Time [s]0 5 10 15

0

1

2

3

Fuelflow

[g/s]

Time [s]

Measurement

Simulation

Reference

Tolerance

0

10

20

30

Velocity[m

ph]

500

1000

1500

2000

2500

Enginespeed[R

PM]

0 5 10 15

0

50

100

150

Enginetorque[N

m]

Time [s]0 5 10 15

0

1

2

3

Fuelflow

[g/s]

Time [s]

Measurement

Simulation

Reference

Tolerance

0

10

20

30

Velocity[m

ph]

500

1000

1500

2000

2500

Enginespeed[R

PM]

0 5 10 15

0

50

100

150

Enginetorque[N

m]

Time [s]0 5 10 15

0

1

2

3

Fuelflow

[g/s]

Time [s]

Measurement

Simulation

Reference

Tolerance

Matlab / Simulink / StateflowParameterized for Cadillac CTSCurb mass: 1725 kg

Powertrain Control (31)/50

To Switch … or not to Switch

Powertrain Control (32)/50

To Switch … or not to Switch

Powertrain Control (33)/50

23.8

24

24.2

24.4

24.6

24.8

Fueleconomy[M

PG] FTP75

1) SI2) SI/HCCI inst.

38.5

39

39.5

40

HWFET

25.5

26

26.5

US06

−1

0

1

2

3

4

ImprovementoverSI[%

]

0

5

10

15

20

HCCIresidence[%

]

0

5

10

15

20

0

5

10

15

20

1) 2) 0

0.5

1

1.5

TRM

S[N

m]

1) 2) 0

0.5

1

1.5

1) 2) 0

0.5

1

1.5

23.8

24

24.2

24.4

24.6

24.8

Fueleconomy[M

PG] FTP75

1) SI2) SI/HCCI inst.

38.5

39

39.5

40

HWFET

3) SI/HCCI NoP

4) SI/HCCI PeP

25.5

26

26.5

US06

−1

0

1

2

3

4

ImprovementoverSI[%

]

0

5

10

15

20

HCCIresidence[%

]

0

5

10

15

20

0

5

10

15

20

1) 2) 3) 4)0

0.5

1

1.5

TRM

S[N

m]

1) 2) 3) 4)0

0.5

1

1.5

1) 2) 3) 4)0

0.5

1

1.5

23.8

24

24.2

24.4

24.6

24.8

Fueleconomy[M

PG] FTP75

1) SI2) SI/HCCI Inst

38.5

39

39.5

40

HWFET

3) SI/HCCI NoP

4) SI/HCCI PeP

25.5

26

26.5

US06

−1

0

1

2

3

4

ImprovementoverSI[%

]

0

5

10

15

20

HCCIresidence[%

]

0

5

10

15

20

0

5

10

15

20

1) 2) 3) 4)0

0.5

1

1.5

TRM

S[N

m]

1) 2) 3) 4)0

0.5

1

1.5

1) 2) 3) 4)0

0.5

1

1.5

23.8

24

24.2

24.4

24.6

24.8

Fueleconomy[M

PG] FTP75

1) SI2) SI/HCCI inst.

38.5

39

39.5

40

HWFET

3) SI/HCCI NoP

4) SI/HCCI PeP

25.5

26

26.5

US06

−1

0

1

2

3

4

ImprovementoverSI[%

]

0

5

10

15

20

HCCIresidence[%

]

0

5

10

15

20

0

5

10

15

20

1) 2) 3) 4)0

0.5

1

1.5

TRM

S[N

m]

1) 2) 3) 4)0

0.5

1

1.5

1) 2) 3) 4)0

0.5

1

1.5

Drive Cycle Results: Penalty and Prediction

Penaltyleads tofueleconomyreduction

Prediction reducesuneccesary switches.

Reduction inHCCIresidencetime

Largereduction indrivertorqueviolations

*Nueschetal.,Isiteconomicalto ignorethedriver?Acasestudyonmultimodecombustion,DSCC2015

Powertrain Control (34)/50

24

24.5

Fueleconomy[M

PG] FTP75

−1

0

1

2

3

4

ImprovementoverSI[%

]

1) SI

2) SI/HCCI inst.

3) SI/HCCI NoP

4) SI/HCCI PeP

0

10

20

HCCIresidence[%

]

1) 2) 3) 4) 0

1

2

TRM

S[N

m]

Ignore the Driver

34

24

24.5

Fueleconomy[M

PG] FTP75

−1

0

1

2

3

4

ImprovementoverSI[%

]

1) SI2) SI/HCCI inst.3) SI/HCCI NoP

4) SI/HCCI PeP

5) SI/HCCI ignore

0

10

20

HCCIresidence[%

]

1) 2) 3) 4) 5)0

1

2

TRM

S[N

m]

1000 1500 2000 2500 3000 3500

0

50

100

150

Engine speed [RPM]

Enginetorque[N

m]

Tim

e (

FT

P75)

[%]

0.0001

0.001

0.01

0.1

1

10

1000 1500 2000 2500 3000 3500

0

50

100

150

Engine speed [RPM]

Enginetorque[N

m]

Tim

e (

FT

P75)

[%]

0.0001

0.001

0.01

0.1

1

10

HCCI

Ignore excursions

Significant impact on driveability

Extended residence time

*Nueschetal.,Isiteconomicalto ignorethedriver?Acasestudyonmultimodecombustion,DSCC2015

Powertrain Control

An electric motor can extend HCCI residence time!

“Thegreaterthehybridization, thelowerthefuelconsumptionreductioninHCCIvehicles.”

[1]

[1]Delormeetal.,EvaluationofHCCIenginesforvariouselectricdriverpowertrains,EVS,2010[2]RickandSisk,Asimulationbasedanalysisof12Vand48Vmicrohybridsystemsacrossvehiclesegmentsanddrivecycles,SAE,2015

• ResidencetimeinHCCIlow• Manymodeswitches

48Vmildhybridelectricvehicleshowgreatpotentialatrelativelylowcost

[2]

HCCI mild-Hybrid

Powertrain Control (36)/50

24

25

26

27

0%

5%

Fuel

economy[M

PG]

FTP75Conv.

1) SI

2) SI/HCCI inst.

39

40

41

42

43

44

45HWFET

Conv.

0%

2.5%

3) SI/HCCI

26

27

28

29

US06Conv.

0%

2.5%

1) 2) 3) 0

20

40

60

HCCIresiden

ce[%

]

1) 2) 3) 0

20

40

60

1) 2) 3) 0

20

40

60

24

25

26

27

0%

5%

0%

5%

Fuel

economy[M

PG]

FTP75Conv. HEV

1) SI

2) SI/HCCI inst.

39

40

41

42

43

44

45HWFET

Conv. HEV

0%

2.5%0%

2.5%

3) SI/HCCI

26

27

28

29

US06Conv. HEV

0%

2.5%

0%

2.5%

1) 2) 3) 1) 2) 3)0

20

40

60

HCCIresiden

ce[%

]

1) 2) 3) 1) 2) 3)0

20

40

60

1) 2) 3) 1) 2) 3)0

20

40

60

Drive Cycle Results: HEV

MildHEVoffersgreatsynergieswithHCCIduringFTP75dueto:• Severalregenerativebraking

periods(≠HWFET)• Frequentlowloaddemand

(≠US06)

• ElectrictorqueassistleadsinsignificantincreaseinHCCIresidencetime

Powertrain Control (37)/50

24

25

26

27

0%

5%

0%

5%

Fuel

economy[M

PG]

FTP75Conv. HEV

1) SI

2) SI/HCCI inst.

39

40

41

42

43

44

45HWFET

Conv. HEV

0%

2.5%0%

2.5%

3) SI/HCCI No storage

26

27

28

29

US06Conv. HEV

0%

2.5%

0%

2.5%

1) 2) 3) 1) 2) 3) CS+0

+20

+40

+60

TailpipeNO

x[m

g/mi]

1) 2) 3) 1) 2) 3) 0

20

40

60

1) 2) 3) 1) 2) 3) 0

20

40

60

24

25

26

27

0%

5%

0%

5%

Fuel

economy[M

PG]

FTP75Conv. HEV

1) SI

2) SI/HCCI inst.

39

40

41

42

43

44

45HWFET

Conv. HEV

0%

2.5%0%

2.5%

3) SI/HCCI No storage

4) SI/HCCI Fil l & deplete

26

27

28

29

US06Conv. HEV

0%

2.5%

0%

2.5%

1) 2) 3) 4) 1) 2) 3) 4)CS+0

+20

+40

+60

TailpipeNO

x[m

g/mi]

1) 2) 3) 4) 1) 2) 3) 4)0

20

40

60

1) 2) 3) 4) 1) 2) 3) 4)0

20

40

60

Drive Cycle Results

• LongHCCIresidencetimeresultsinlargeNOxquantities

• SignificanttailpipeNOx

LEVIII SULEV20 & EPA Tier 3 Bin20: 20 mg/mi NOx + NMOG (incl. cold start)

Powertrain Control (38)/50

HCCI Operation with mild-HEV

1000 1500 2000 2500 3000

0

5

10

15

HCCI

Conventional SI/HCCI I

Engine Speed ωe [RPM]

SI min

SI max

BMEP

[bar]

1000 1500 2000 2500 3000

HEV SI/HCCI IV

Engine Speed ωe [RPM]

Tim

e [%

]

0.0001

0.001

0.01

0.1

1

10

FTP75

• ReductioninengineoperationrightaboveandbelowHCCIregime

Powertrain Control (39)/50

We…Ø AFRislowØ EfficiencybenefitsdiminishØ NOx is“high”

Ø BreakthroughsoccuranywayØ Depletionisexpensive

• usedaTWCwithgenerousO2-storagetopreventNOxbreakthroughs

• pushedHCCItohigherloads

Ø Reduceregimetolowload

Ø ReducesizeofO2-storage

Bigger always better?

*Nueschetal.,Mild HEV with Multimode Combustion:Benefits of a Small Oxygen Storage,IFAC-AAC2016

Powertrain Control (40)/50

FRVVT

VVLGDI TRBDS-1

TRBDS-2

TRBDS-3

DIESEL

HEV

xEV MPGe(estimated)

2025 Target

Technology Cost Effectiveness

?

-- Highly Diluted e/iEGR-- Stoichiometric (TWC)-- Spark Assisted HCCI (SACI)

High CV and misfires areChallenges!!

Powertrain Control (41)/50

SparkAssistedCompression Ignition

Powertrain Control (42)/50

SACI combustion: Random High CV

Powertrain Control (43)/50

Spark Ignition at High DilutionRandom High CV

The Cyclic Variability (CV) in spark ignition was fitted (brute force) but

it can also be modeled using kernel initiation physics!!

(ASME-ICEF2016)

H.Lian, et al: “Prediction of Early Flame Burning Velocity with High Exhaust Gas Recirculation (EGR) and Spark Advance, ASME-ICEF2016-9476

Implication:Control SI combustion at the limits of high EGR dilution (misfires).

Powertrain Control (44)/50

Several factors reduce previously stated SI/HCCI fuel economy benefits. Many opportunities ahead:1. Spark Assisted HCCI (Stoichiometric extension at high load)2. Mode switches with two valve lifts3. Some NOx aftertreatment

Results• Highlighted in 2014 DOE Merit Review and 2015 NRC Report

Highlights the importance of comprehensive system analysis when evaluating advanced engine concepts.

Contributions & Lessons Learnt

Powertrain Control (45)/50

[41] P. Gorzelic, et al, “A low-order adaptive engine model for SI-HCCI mode transition controlapplications with cam switching strategies”, International Journal of Engine Research, June 2015. DOI: 10.1177/1468087415585016[40] S. Nüesch, et al, “Accounting for Combustion Mode Switch Dynamics andFuel Penalties in Drive Cycle Fuel Economy”, International Journal of Engine Research, May 2015. [39] J. Larimore, et al, “Adaptive Control of a Recompression Four-Cylinder Engine”, IEEE Trans on Control Systems Technology, Mar 2015, DOI: 10.1109/ TCST.2015.2402235[38] S. Nüesch, et al, "Fuel Economy of a Multimode Combustion Engine with Three-Way Catalytic Converter", ASME Journal of Dynamic Systems, Measurement, and Control, v 137, i 5, p 051007, [37] S. Jade, et al. Controlled load and speed transitions in a multicylinder recompression hcci engine. IEEE Trans on Control Systems Techn, September 2014. [36] E. Hellström at al. Reducing cyclic variability while regulating combustion phasing in a four-cylinder hcciengine. IEEE Trans on Control Systems Tech, May 2014. [34] P. Gorzelic et alA low-order hcci model extended to capture si-hcci mode transition data with two-stage cam switching. In ASME Dynamic Systems and Control Conference (DSCC), San Antonio, October [33] E. Hellström et al. A linear least-squares algorithm for double-wiebe functions applied to spark-assisted compression ignition. Journal of Engineering for Gas Turbines and Power, 136(9), 2014. [ bi[32] J Larimore et al. Real-time internal residual mass estimation for combustion with high cyclic variability. International J of Engine Research, Cyclic Dispersion Special Issue, 2014. [ bib | DOI ][31] S Nüesch et al. Mode switches among si, saci, and hcci combustion and their influence on drive cycle fuel economy. In in Proceedings of American Control Conference (ACC) 4[30] S Nüesch et al. Methodology to evaluate the fuel economy of a multimode combustion engine with three-way catalytic converter. In ASME Dynamic Systems and Control Conference (DSCC), San Antonio, October 2014, DSCC2014[29] Sa P. Nüesch et al. Methodology to evaluate the fuel economy of a multimode combustion engine with three-way catalytic converter. Journal of Dynamic Systems Measurement and Control, 137(5), 2014. [ bib | DOI ][28] E. Hellström et al. Cyclic variability and dynamical instabilities in autoignition engines with high residuals. IEEE Transactions on Control Systems Technology, 21(5):1527[27] E. Hellström et al. A linear least-squares algorithm for double-wiebe functions applied to spark-assisted compression ignition. In ASME 2013 Internal Combustion Engine Division Fall Technical Confe[26] S. Jade et al Enabling large load transitions on multicylinder recompression hcciengines using fuel governors. In in Proc. American Control Conference, pages 4423[25] J. Larimore et al. 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Powertrain Control

Thanks toJason Martz, Huan Lian, Niket Prakash, Rasoul Salehi, Erik HellstromShyam Jade, Jacob Larimore, Sandro Nuesch, Pat Gorzelic (UMICH)

Dan Hussey, David Jacobson (NIST),

National Science FoundationUS Department of Energy,

ARPA-E,US Army

with Bosch, Daimler, Ford, Toyota

Thank You!!