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Appendix 7a F1

United Kingdom

Original text. Later amendments are not shown.

Verification of trip dynamics

1.

INTRODUCTION

This Appendix describes the calculation procedures to verify the trip dynamics by determining the excess or absence of dynamics during urban, rural and motorway driving.

2.

SYMBOLS, PARAMETERS AND UNITS

RPA

Relative Positive Acceleration

Δ
  • difference

  • >
  • larger

  • ≥
  • larger or equal

  • %
  • per cent

  • <
  • smaller

  • ≤
  • smaller or equal

  • a
  • acceleration [m/s2]

  • ai
  • acceleration in time step i [m/s2]

  • apos
  • positive acceleration greater than 0,1 m/s2 [m/s2]

  • apos,i,k
  • positive acceleration greater than 0,1 m/s2 in time step i considering the urban, rural and motorway shares [m/s2]

  • ares
  • acceleration resolution [m/s2]

  • di
  • distance covered in time step i [m]

  • di,k
  • distance covered in time step i considering the urban, rural and motorway shares [m]

  • Index (i)
  • discrete time step

  • Index (j)
  • discrete time step of positive acceleration datasets

  • Index (k)
  • refers to the respective category (t=total, u=urban, r=rural, m=motorway)

  • Mk
  • number of samples for urban, rural and motorway shares with positive acceleration greater than 0,1 m/s2

  • Nk
  • total number of samples for the urban, rural and motorway shares and the complete trip

  • RPAk
  • relative positive acceleration for urban, rural and motorway shares [m/s2 or kWs/(kg*km)]

  • tk
  • duration of the urban, rural and motorway shares and the complete trip [s]

  • T4253H
  • compound data smoother

  • ν
  • vehicle speed [km/h]

  • νi
  • actual vehicle speed in time step i [km/h]

  • νi,k
  • actual vehicle speed in time step i considering the urban, rural and motorway shares [km/h]

  • ν× ai
  • actual vehicle speed per acceleration in time step i [m2/s3 or W/kg]

  • ν× aposj,k
  • actual vehicle speed per positive acceleration greater than 0,1 m/s2 in time step j considering the urban, rural and motorway shares [m2/s3 or W/kg].

  • ν× aposk−95
  • 95th percentile of the product of vehicle speed per positive acceleration greater than 0,1 m/s2 for urban, rural and motorway shares [m2/s3 or W/kg]

  • ν–k
  • average vehicle speed for urban, rural and motorway shares [km/h]

  • 3.

    TRIP INDICATORS

    3.1.

    Calculations

    3.1.1.

    Data pre-processing

    Dynamic parameters like acceleration, (v · apos) or RPA shall be determined with a speed signal of an accuracy of 0,1 % for all speed values above 3 km/h and a sampling frequency of 1 Hz. This accuracy requirement is generally fulfilled by distance calibrated signals obtained from a wheel (rotational) speed sensor. Otherwise, acceleration shall be determined with an accuracy of 0,01 m/s2 and a sampling frequency of 1 Hz. In this case the separate speed signal, in (v · apos), shall have an accuracy of at least 0,1 km/h.

    The correct speed trace builds the basis for further calculations and binning as described in paragraph 3.1.2 and 3.1.3.

    3.1.2.

    Calculation of distance, acceleration and ν× a

    The following calculations shall be performed over the whole time based speed trace (1 Hz resolution) from second 1 to second tt (last second).

    The distance increment per data sample shall be calculated as follows:

    X1di=vi3,6, i= 1 to Nt

    where:

    di
  • is the distance covered in time step i [m]

  • νi
  • is the actual vehicle speed in time step i [km/h]

  • Nt
  • is the total number of samples

  • The acceleration shall be calculated as follows:

    ai=vi+ 1− vi− 1∕2× 3,6, i= 1 to Nt

    where:

    ai
  • is the acceleration in time step i [m/s2]. For i = 1: vi-1= 0, for i= Nt: vi+ 1= 0.

  • The product of vehicle speed per acceleration shall be calculated as follows:

    v× ai=vi× ai∕ 3,6, i= 1 to Nt

    where:

    ν× ai
  • is the product of the actual vehicle speed per acceleration in time step i [m2/s3 or W/kg].

  • 3.1.3.

    Binning of the results

    After the calculation of ai and (v · a)i, the values vi, di, ai and (v · a)i shall be ranked in ascending order of the vehicle speed.

    All datasets with vi ≤ 60 km/h belong to the ‘urban’ speed bin, all datasets with 60 km/h < vi ≤ 90 km/h belong to the ‘rural’ speed bin and all datasets with vi > 90 km/h belong to the ‘motorway’ speed bin.

    For N2 category vehicles that are equipped with a device limiting vehicle speed to 90 km/h, all datasets with vi ≤ 60 km/h belong to the ‘urban’ speed bin, all datasets with 60 km/h < vi ≤ 80 km/h belong to the ‘rural’ speed bin and all datasets with vi > 80 km/h belong to the ‘motorway’ speed bin.

    The number of datasets with acceleration values ai > 0,1 m/s2 shall be greater or equal to 100 in each speed bin.

    For each speed bin the average vehicle speed v–k shall be calculated as follows:

    v–k=∑ivi,k∕Nk, i = 1 to Nk, k= u, r, m

    Where:

    Nk is the total number of samples of the urban, rural, and motorway shares.

    3.1.4.

    Calculation of v× apos−95 per speed bin

    The 95th percentile of the v× apos values shall be calculated as follows:

    The v× ai,k values in each speed bin shall be ranked in ascending order for all datasets with ai,k> 0,1 m∕s2ai,k≥ 0,1 m∕s2 and the total number of these samples Mk shall be determined.

    Percentile values are then assigned to the v× aposi,k values with ai,k≥ 0,1 m∕s2 as follows:

    The lowest v× apos value gets the percentile 1/Mk, the second lowest 2/Mk, the third lowest 3/Mk and the highest value Mk∕Mk= 100 %.

    v× aposk−95 is the v× aposj,k value, with j∕Mk= 95 %. If j∕Mk= 95 %. cannot be met, v× aposk−95 shall be calculated by linear interpolation between consecutive samples j and j+1 with j∕Mk< 95 % and j+ 1∕Mk> 95 %.

    The relative positive acceleration per speed bin shall be calculated as follows:

    RPAk=∑jΔt×v× aposj,k∕∑ i di,k,j= 1 to Mk, i= 1 to Nk, k= u,r,m

    where:

    RPAk
  • is the relative positive acceleration for urban, rural and motorway shares in [m/s2 or kWs/(kg*km)]

  • Δt
  • is a time difference equal to 1 second

  • Mk
  • is the sample number for urban, rural and motorway shares with positive acceleration

  • Nk
  • is the total sample number for urban, rural and motorway shares

  • 4.

    VERIFICATION OF TRIP VALIDITY

    4.1.1.

    Verification of v× apos−95 per speed bin (with v in [km/h])

    If v–k≤ 74,6km∕h

    and

    v× aposk− 95>0,136× v–k+ 14,44

    is fulfilled, the trip is invalid.

    If v–k> 74,6km∕h and v× aposk−95>0,0742×v–k+ 18,966 is fulfilled, the trip is invalid.

    F2Upon the request of the manufacturer, and only for those N1 or N2 vehicles where the vehicle power-to-mass ratio is less than or equal to 44 W/kg then:

    If v–k≤74,6 km∕h

    and

    v×aposk _95>0,136×v–k+14,44

    is fulfilled, the trip is invalid.

    If v–k>74,6 km∕h

    and

    v×aposk _95>−0,097×v–k+31,635

    is fulfilled, the trip is invalid.

    To calculate the power-to-mass ratio, the following values shall be used:

    • the mass which corresponds to the actual test mass of the vehicle including the drivers and the PEMS equipment (kg);

    • the maximum rated engine power as declared by the manufacturer (W).

    4.1.2.

    Verification of RPA per speed bin

    If v–k≤94,05 km∕h and RPAk<−0,0016×v–k+0,1755 is fulfilled, the trip is invalid.

    If v–k>94,05 km∕h and RPAk < 0,025 is fulfilled, the trip is invalid.

    Annotations

    Textual amendments

    F1

    Substituted by Commission Regulation (EU) 2018/1832 of 5 November 2018 amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) 2017/1151 for the purpose of improving the emission type approval tests and procedures for light passenger and commercial vehicles, including those for in-service conformity and real-driving emissions and introducing devices for monitoring the consumption of fuel and electric energy (Text with EEA relevance).

    F2

    Inserted by Commission Regulation (EU) 2018/1832 of 5 November 2018 amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) 2017/1151 for the purpose of improving the emission type approval tests and procedures for light passenger and commercial vehicles, including those for in-service conformity and real-driving emissions and introducing devices for monitoring the consumption of fuel and electric energy (Text with EEA relevance).

    Editorial notes

    X1

    Substituted by Corrigendum to Commission Regulation (EU) 2017/1151 of 1 June 2017 supplementing Regulation (EC) No 715/2007 of the European Parliament and of the Council on type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information, amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) No 1230/2012 and repealing Commission Regulation (EC) No 692/2008 (Official Journal of the European Union L 175 of 7 July 2017).