1. Pilot phase - Learnings
Editing board meeting
ACEA CO2WG TF1

2. Installation of the vehicle
Pilot phase learnings
Overview
Each OEM has provided the outcome of his “playing certification”.
Each OEM has given his amendments/learnings to the TUG in the form of a standard excel file.
Up to 50 amendments/learnings per OEM were provided.
The technical annex working groups need to discuss/reflect all items
Example items out of excel lists: 16
MAN Truck & Bus AG
Björn Marks
Axle
Item 3.2.7
Data processing
- Controllability of set point: „The range of the output torque values for the four results per grid point shall not exceed 20 Nm (+/- 10 Nm) or 1% of set point torque, whichever is the higher value.” - Requested repeat accuracy does not comply to all measurement points - Proposal: Extension of range to 40 Nm or 2% of set point torque - To be defined in technical annex, item 3.2.7: - Explicit provisions for calculation of repeat accuracy - Procedure for set points which does not comply with the the requested repeat accuracy. Options to be discussed: a.) Clip value from worst neighboring point. b.) Abolition and interpolation of those points as far as interpolated points do not exceed more than 10% of all points in the map? c.) Penalty of 5% for those set points? d.) Repetition of measurement for those set points within 20 hours of timeframe for test bench measurements? e.) Abolition and repetition of the entire series of measurement? 18
Stephan Kopp
Air Drag
Item 3.4; subitem "v."
Installation of the vehicle
[…] „Tyres inflated to the highest allowable pressure” - Tyre pressure (not exactly defined: during Playing Certifcation: according to manufacturers instruction (MAN approach: according to test weight) - Tyre pressure measurement (before warm-up of vehicle) at which temperature? - MAN recommends: cold conditions

3. Test procedure updates
pilot phase - Learnings
TF1 – Engine testing
Engine tool updates
Some modifications in VECTO engine tool are necessary
Specific test bench layouts.
Representative dynamic correction (“WHTC correction factor”) under all driving conditions.
Calculation rules in VECTO engine tool have to be transparently documented. Embedding of calculations into several test bed systems should be facilitated.
Tighten standardization of map grid values to be measured (number of values).
Definitions for CO2 and NOx emission demonstration are different. Some modifications on some procedural definitions are needed:
Ensure consistency between CO2 and emission test definitions (e.g. detailed test definitions, auxiliaries,…). Link to legal emission tests has to be ensured.
WHTC correction factors for CO2 shall be determined taking into account point a.
Finalizing CO2 cluster concept (“engine family”) considering accuracy and emission consistency appropriately
Proposal for extension of COP concept for engine performance and emissions regarding certified CO2/FC engine data.
Test procedure updates

4. pilot phase - Learnings
TF1 – Transmission testing
Temperatures (wording was already changed by expert group)
The wording defining the allowed temperature range was changed to be comparable to the technical annex of axles. This leads to the possibility to do measurements without an additional heating.
Calculation of uncertainty – factor “w_para” to be reviewed
The factors for the parasitic loads (w_para: 100%, 50%, and 20%) seem to be very high.
An option 3 measurement with a test rig setup which is not perfect (for example only one bearing beside the torque sensor  w_para=100%) leads to worse values than using option 2.
The test procedure according to Option 2 is possible to follow and produces relevant and meaningful results, minor clarifications are necessary.
Transmission oil temperature in the test must be revised. Different temperature than in the vehicle gives incitement to introduce oil that is optimal for test conditions but sub-optimal for actual conditions.
Transmission measurement ranges should be fixed and limited to relevant operating points. Not subject to specific vehicle specifications within a vehicle class (independent of engine power and tyre size)
A transmission post processing (VECTO transmission) tool is necessary to
Check the measurement data on completeness and correctness.
Guarantee that the measurement data are processed according to the technical annex and in the same way by all manufacturers
Ensure the authenticity and traceability of the VECTO vehicle simulation input data.
Use the VECTO input(files) as data-exchange-format, e.g. with suppliers.
The family concept needs to be verifiable in practice.
Test options
TM tool definition

5. Test procedure details
pilot phase - Learnings
TF1 – Axle testing (1/3)
Test procedure details
Calculation of parasitic losses to be reviewed
Axle measurements should be fixed and limited to relevant operating points. Not subject to specific vehicle specifications within a vehicle class (independent of engine power and tyre size)
Measurement of hub reduction gear axles in 2 machine test rig layout (L-configuration) brings along technical problems regarding cooling. (See technical annex Item 2.3.2)
Proposal: hub reduction gear axles shall also be measured in a 3 machine layout
The tolerances considering the controllability of the set point should be redefined. They can currently not be met for all measuring points. As an alternative, a procedure for set points which do not comply with the requested repeat accuracy should be defined
It was possible to successfully complete the axle test and to deliver the required data.
Technical Annex contains many details in measurement conditions and design specifications:
that are not objectively verifiable in a practical way
neither have a substantial contribution to the CO2 contribution of the axle to the vehicle ( e.g. distance gear to wall, alignment of axle, sealing specs.)
Design characteristics for family concept are too detailed for use in practice
To be defined in technical annex, item 3.2.7:
Explicit provisions for calculation of repeat accuracy
Procedure for set points which do not comply with the requested repeat accuracy.    

6. Review and update of annexes
pilot phase - Learnings
TF1 – Axle testing (2/3)
Conditions are not always clear specified for verification, e.g.:
Oil filling level
Lack of bandwidth specifications
Measurement range is not defined in a practical way, e.g. has too much interaction with engine / vehicle release data
Maximum power to much dependent of actual vehicle release data
Test range for torques and extrapolation method.
Test range for minimum rpm not practical (tyres change!)
Calibration requirements
Not always clearly specified how to make these verifiable in practice (e.g. rpm)
Descriptions in T.A. not always clear and unambiguous (example: text about run-in times etc.)
Review technical annex in expert group (same for all annexes):
Which information can be removed because it is not necessary e.g. does not have substantial influence on the CO2 contribution of the axle
Which data entries and tolerances should be extended to avoid unnecessary test burden and limitations.
Which descriptions of conditions should be adapted to make these objectively verifiable in practice.
To improve the text where it is unclear, incomplete or ambiguous
Apply commonly used homologation jargon & procedures.
Review and update of annexes

7. pilot phase - Learnings
TF1 – Axle testing (3/3)
Axle tool definition
An axle post processing (VECTO axle) tool is necessary to
Check the measurement data on completeness and correctness.
Guarantee that the measurement data are processed according to the technical annex and in the same way by all manufacturers
Ensure the authenticity and traceability of the VECTO vehicle simulation input data.
Use the VECTO input(files) as data-exchange-format, e.g. with suppliers.
The family concept needs to be verifiable in practice.

8. pilot phase - Learnings
TF1 – Air drag testing (1/2)
CSE update needed
CSE tool to be improved:
Measurement data (sets) are accepted by the CSE tool although Technical Annex is not fulfilled. Errors should be removed.
Validation check needs too much time. The results should be available during the test.
Error messages often unclear and should be improved
A possibility should be created to allow for diagnosis of unaccepted data
Enable first processing all measurement data in one direction and consequently all data in the other direction (as is allowed in the technical annex)
Review tolerances/handling (minimum limit of valid laps is difficult to reach and to detect when minimum is reached)
Ambient conditions and torque variations
Maximum allowed peak torque variation, especially on low speed rounds
Minimum drift limits of the torque wheels difficult to reach
Lifting the torque measuring axle on track
Torque limitation representing brake drag and axle losses
Tyre profile maximum depth should be revised in technical annex to avoid frequent tyre changes on measurement rims.
Limits for ambient conditions need to be reviewed e.g. for tarmac temperatures. This might be dependent from test track.
Repeatability tests with CSE showed errors up to 12% in Cd value.
Review ongoing

9. pilot phase - Learnings
TF1 – Air drag testing (2/2)
Some class 1-3 truck combinations exceed speed corridor for low-speed measurements (10-15 km/h) due to the standard powertrain configuration
Kistler does not guarantee torque accuracy as required in Technical Annex. The Kistler torque quality spec should be accepted or calibration procedure added
Calibration of the wind meter acc. to ISO cannot be met (low speed) or is not suitable (high speed). Review criteria
Requirements regarding trailers and boxes are strict. Box body dimensions and trailer dimensions to comply with should have clear definitions and practical tolerances for dimensions that have negligble influence on the test outcome. Also for easier check by technical service (-> ClCCR, aero group)
General: Technical annex contains many recommendations that are not verifiable (no quantification) and often not necessary or redundant for legislation. These statements are best practices and should not be part of legislative text.
Measurement conditions for vehicles with controllable aerodynamic devices are not defined in Technical Annex.
Investigate the balance between higher stability of torque and speed signal with higher weights and lower rolling drag contribution with unladen situation to arrive at maximum accuracy and repeatability.
Review tyre pressure specification and definition.
CLCCR task
Update of annexes