1. LDV Real Driving Emissions: - Assessment of MAW evaluation method: Sensitivity study -
RDE Task Force Meeting, 28th November 2013, Brussels
Theodoros Vlachos, Martin Weiss, Pierre Bonnel - European Commission DG - Joint Research Centre (JRC) - IET - Institute for Energy and Transport

2. Objectives Proposal of an analysis for data evaluation EMROAD v5.7
V002 NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
Main results obtained: weighted emissions calculated on the basis of indicators compared to the average calculated on total trips for vehicle 2
EMROAD v5.7

3. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Conclusions

4. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Conclusions

5. Assessment criteria (1/1)
ROBUSTNESS:
Ability to evaluate testing conditions (trip)
Data coverage
Ability to assess RDE performance
Ability to assess RDE performance under specific testing conditions
Robustness against uncertainties of data acquisition and data evaluation
Technological neutrality
PRACTICABILITY:
PEMS testing effort
Availability and accuracy/reliability of input parameters
Simplicity of calculation steps
Possibility for independent RDE testing
Flexibility to be adapted to future emissions legislation

6. Outline Assessment Criteria Proposed analysis per assessment criterion
Results
Conclusions

7. Robustness Analysis (1/2)
Analysis and results required from the different tools:
Assessment Criterion
Analysis
ROBUSTNESS
A. Ability to evaluate testing conditions (trip)
Generic trip characteristics (all methods)
B. Data coverage
Results from indicators (method specific or not)
C. Ability to assess RDE performance
Total emissions [g/km] with and without data exclusion for all tests:
I. Taking into account all driving conditions (normal, severe, soft)
II. For normal driving only
D. Ability to assess RDE performance under specific testing conditions
For normal driving only (for all tests):
I. Average emissions [g/km] for U/R/M, separately, with and without data exclusion
II. Distance weighted emissions [g/km] with and without data exclusion

8. Robustness Analysis (2/2)
Analysis and results required from the different tools:
Assessment Criterion
Analysis
ROBUSTNESS
E. Robustness against uncertainties of data acquisition and data evaluation
Case studies
Data uncertainties: Sensitivity studies
Robustness of data evaluation 1:
Performance of the RDE method for specific testing situations
Roundtrip clockwise and counterclockwise driving
Aggressive versus soft or normal driving style
Aggressive driving during part of a test
Robustness of data evaluation 2:
Sensitivity of the RDE method to their design parameters
F. Technology neutrality
Description of the principles envisaged to adapt the methods to hybrid powertrains and alternative fuels
(Discussion) Implications in terms of testing (Parameters and quality required)
(Possibly) case studies with results (as for criteria A, B, C, D)

9. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Robustness against uncertainties of data evaluation
Conclusions
We provide a series of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

10. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Robustness against uncertainties of data evaluation
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

11. Testing Conditions
MAW were categorized in 3 different testing conditions:
Normal driving (MAW within Normal Driving Upper & Lower Bounds);
Severe driving (MAW within Severe & Normal Driving Upper Bounds);
Soft driving (MAW within Severe & Normal Driving Lower Bounds).
Several Driving – Upper Bound
Vehicle CO2 Characteristic Curve corrected for on-road
Sever Testing Conditions
Normal Driving – Upper Bound
Normal Testing Conditions
Normal Driving – Lower Bound
Soft Testing Conditions
Several Driving – Lower Bound
Vehicle CO2 Characteristic Curve vs. Vehicle Speed
(EMROAD v5.7)
A tolerance of 25% respect vehicle CO2 characteristic curve was used for defining “Normal driving region”
Categorization of the severity is based on MAW CO2 [g/km] with respect to vehicle CO2 characteristic curve.
EMROAD v5.7

12. Vehicle Speed Binning
MAW were categorized in 3 different vehicle speed bins:
Urban driving (U) (0≤ Veh.SpeedMAW [km/h] >45);
Rural driving (R)(45≤ Veh.SpeedMAW [km/h] ≥80);
Motorway driving (M) (80≤ Veh.SpeedMAW [km/h]).
Urban
Rural
Motorway
Sever Testing Conditions
Vehicle CO2 Characteristic Curve corrected for on-road
Normal Testing Conditions
Soft Testing Conditions
Vehicle CO2 Characteristic Curve vs. Veh. Speed
(EMROAD v5.7)
EMROAD v5.7

13. Indicator for trip validation
Validation based on trip portion within Normal Driving Conditions.
A “sufficient number (share)” of MAW is needed for all vehicle speed bins: U+R+M.
Sufficient Number (Share) of MAW: percentage of MAW within Urban, Rural and Motorway bins respect to total number of Normal MAW.
A target of 10% of MAW was adopted as “sufficient number (share)” of windows.
SEVERITY CATEGORY
ALL DRIVING
NORMAL DRIVING
Urban
Rural
Motorway
All
MAW #
1319
1785
2609
5713
1618
1870
4807
MAWdriving conditions [%]
23.08
31.24
45.67
100
27.44
33.66
38.90
This metric defines the contribution of U/R/M in Normal driving testing.
=23.08
=38.90

14. Indicator for trip validation
Validation based on trip portion within Normal Driving Conditions.
A “sufficient number (share)” of MAW is needed for all vehicle speed bins: U+R+M.
Sufficient Number (Share) of MAW: percentage of MAW within Urban, Rural and Motorway bins respect to total number of Normal MAW.
Weight factor of 0.33 was used for Urban, Rural and Motorway vehicle speed bins.
A target of 10% of MAW was adopted as “sufficient number (share)” of windows.
V002 NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
EMROAD v5.7

15. Data Coverage (V002) (1/1)
Vehicle CO2 Characteristic Curve and MAW Share vs. Vehicle Speed:
Vehicle CO2 Characteristic Curve vs. Veh. Speed
Share of Normal MAW
Besides n-WLTC, SCM and R#3 routes do not show a sufficient number of MAW during motorway => NOT VALID trips (see next slides) => to be COMPLEMENTED
EMROAD v5.7

16. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Routes Comparison
Driving style Comparison (same Route)
Robustness against uncertainties of data evaluation
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

17. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Routes Comparison
Driving style Comparison (same Route)
Robustness against uncertainties of data evaluation
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

18. Routes Comparison (V002) (1/1)
Weighted NOx emissions vs. Routes:
Share of Normal MAW
V002 NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
No valid routes: n-WLTC, SCM, R#3.
Tests should/could be complemented.
Open issues: driving routes design (e.g. vehicle speed dynamics, U/R/M shares….)
EMROAD v5.7

19. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Routes Comparison
Driving style Comparison (same Route)
Robustness against uncertainties of data evaluation
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

20. Driving Style Comp. (V002) (1/1)
Vehicle CO2 Char. Curve, MAW Shares and weighted emissions vs. Vehicle Speed:
Share of Normal MAW
NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
Routes characteristics (see previous slides) and vehicle dynamics could have a significant impact on emissions.
Vehicle CO2 Characteristic Curve vs. Veh. Speed
Significant changes in both MAW distribution across vehicle CO2 char. curve and NOx weighted emissions.
EMROAD v5.7

21. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Robustness against uncertainties of data evaluation
Repeatability Check
Sensitivity on data exclusion
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

22. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Robustness against uncertainties of data evaluation
Repeatability Check
Sensitivity on data exclusion
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

23. Repeatability Check (V002) (1/1)
Vehicle CO2 Char. Curve vs. Veh. Speed:
NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
Share of Normal MAW
A maximum deviation among results obtained by tests on the same vehicle, route and driving style should be taken into account.
Vehicle CO2 Characteristic Curve vs. Veh. Speed
A variation of 15% among trips was observed as far as NOx emissions is concerned.
A variation of 17% among trips was observed as far as MAW is concerned.
EMROAD v5.7

24. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Data coverage
Ability to assess RDE performance
Robustness against uncertainties of data evaluation
Repeatability Check
Sensitivity on data exclusion
Conclusions
We provide a sereis of presentations with the totality of the results for the three vehicles, but for sake of brevity I will focus on soe of these

25. Data Exclusion (V001) (1/1) Vehicle CO2 Char. Curve vs. Veh. Speed:
NOx Emissions:
Statistical Analysis
(Weighted Emissions)
W_NOT==0
The application of exclusion criteria should be applied carefully. A detailed definition of how should be applied is needed (periodic regeneration effects, cold start, idling…)
Vehicle CO2 Characteristic Curve vs. Veh. Speed
Specific emissions can detect differences on emission levels. CO2 specific emissions seem to be less sensitive.
Idling exclusion could be significant in case of MAW results.
EMROAD v5.7

26. Outline Assessment Criteria
Summary of analysis to be conducted per criterion
Results
Conclusions

27. Conclusions Assessment Criterion Analysis Effects ROBUSTNESS
B. Data coverage
Indicators adoption
Validate/invalidate trips
Complementing invalidate trips
B and C. Ability to assess RDE performance
Total emissions [g/km], average emissions for U/R/M, distance weighted emissions with and without data exclusion for all tests.
Route design
Vehicle dynamics
E. Robustness against uncertainties of data acquisition and data evaluation
Case studies (repeatability check)
Definition of a tollerance for repeatability check.
Driving style effects
Vehicle dynamics should be taken into acount.

28. For further information, please contact:
Theodoros Vlachos – EC JRC –
Pierre Bonnel – EC JRC –

29. LDV Real Driving Emissions: - Assessment of MAW evaluation method: Sensitivity study -
RDE Task Force Meeting, 28th November 2013, Brussels
Theodoros Vlachos, Martin Weiss, Pierre Bonnel - European Commission DG - Joint Research Centre (JRC) - IET - Institute for Energy and Transport