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Users Manual for Program TRC_IPLAS4





Table of Contents

   Introduction
   Input data commands
   Input data Example
   Output data Example




Introduction

Program TRC_IPLAS4 is designed for translating track measurements made by track recording cars based on versine measurements.

The geometry of the track recording car is described with the following commands:

axelpos_cant = 0.         # Position of the wheelset measuring cant
axelpos_gauge= 0.         # Position of the wheelset measuring gauge
axelpos_level  =  0.      # Position of the wheelset measuring vertical level
axelpos_level_1= -2.      # Position of the counter axle 1 measuring vertical level
axelpos_level_2=  3.      # Position of the counter axle 2 measuring vertical level
axelpos_versine  =  0.    # Position of the wheelset measuring horizontal versine
axelpos_versine_1= -5.    # Position of the counter axle 1 measuring horizontal versine
axelpos_versine_2=  5.    # Position of the counter axle 2 measuring horizontal versine

Input data INFIL is read from a CSV-file. The columns are selected with the following commands:

icol_km= 1                # Kilometer
icol_m = 2                # Meter
icol_vertl= 4             # Vertical left rail
icol_vertr= 3             # Vertical right rail
icol_cant = 5             # Cant
icol_latl = 8             # Lateral left rail
icol_latr = 7             # Lateral right rail
icol_gauge= 9             # Gauge

And scaled with the following commands:

scale_vertl=    1         # Vertical left rail
scale_vertr=    1         # Vertical right rail
scale_cant =    1         # Cant
scale_latl =    1         # Lateral left rail
scale_latr =    1         # Lateral right rail
scale_gauge=    1         # Gauge

The output data file UTFIL is written in trax_wdesign-format. Since the transfer function of the track measuring car is not good for some waves lengths, the transfer function back to Cartesian coordinates cannot be ideal, it must be filtered and delimited. The filters can be defined with the commands:

L_SHORT_WAVES
L_LATERAL_WAVES

See also:

TRC_PLAS Calculates versines of the columns in a track irregularity file


Input data commands

Input data is read in free format, valid separators between the input values are <space>, <comma>, <tab>, <equal sign> or <carriage return>. The commands can be written both in lower and upper case letters. The operation of the program is controlled by the commands described below; some of the commands also need arguments.


VEHICLE_DIRECTION
'A' If the A-end of the measuring-trolley is facing towards increasing kilometers of the track.
'B' If the B-end of the measuring-trolley is facing towards increasing kilometers of the track.
Declared= Character*1    Default= Blank

L_SHORT_WAVES
Low pass filter cut-off frequency.
Track irregularities of very high frequencies can be measured in the STRIX track measuring car. However too short waves in the track are not of interest, if the track is going to be used for estimation of ride comfort and lateral track forces only. The short waves makes simulation times longer, because the integrate needs to make smaller time-steps.
Declared= Real*4    Default= 1.2 [m]

N_SHORT_WAVES
Order of the low pass filter.
The filter is of type Butterworth in two stages. First forward filtering then backward filtering. This type of filtering avoids different delays for different wave lengths. N_SHORT_WAVES must be an even number.
Declared= Integer*4    Default= 16

L_LATERAL_WAVES
High pass filter cut-off frequency for lateral track irregularities.
Declared= Real*4    Default= 55.55 [m]

N_LATERAL_WAVES
Order of the lateral high pass filter.
The filter is of type Butterworth in two stages. First forward filtering then backward filtering. This type of filtering avoids different delays for different waves. N_LATERAL_WAVES must be an even number.
Declared= Integer*4    Default= 6

XSTART_KM
Defines the first kilometer from where the translation shall begin.
Declared= Real*4    Default= -1000000

XSTART_M
Defines the meter within the first kilometer from where the translation shall begin.
Declared= Real*4    Default= -1000

XSTOP_KM
Defines the last kilometer where the translation shall end.
Declared= Real*4    Default= 1000000

XSTOP_M
Defines the meter within the last kilometer where the translation shall end.
Declared= Real*4    Default= 1000

INFIL
File containing the track measurements written in *.CSV-format. However only the columns for short waves irregularities are used.
Declared= Character*132    Default= Blank

UTFIL
File containing the output data, written in *.trax-format.
Declared= Character*132    Default= Blank

NCOLS
Number of columns in INFIL.
Declared= Integer*4    Default= 0

DX
Equidistant step between the interpolated points in the X-axis.
The FFT-algorithm in the backward transformation requires that the points in input data have equidistant distances in their X-axles. Therefore the curves read from INFIL always will be interpolated before any calculations takes place.
Declared= Real*4    Default= 0.

AXLEPOS_CANT
Longitudinal position of the wheelset measuring cant.
Declared= Real*4    Default= 0.

AXLEPOS_GAUGE
Longitudinal position of the wheelset measuring gauge.
Declared= Real*4    Default= 0.

AXLEPOS_LEVEL
Longitudinal position of the wheelset measuring vertical level.
Declared= Real*4    Default= 0.

AXLEPOS_LEVEL_1
Longitudinal position of counter axle 1 measuring vertical level.
Declared= Real*4    Default= -2.

AXLEPOS_LEVEL_2
Longitudinal position of counter axle 2 measuring vertical level.
Declared= Real*4    Default= 3.

AXLEPOS_VERSINE
Longitudinal position of the wheelset measuring lateral versine.
Declared= Real*4    Default= 0.

AXLEPOS_VERSINE_1
Longitudinal position of counter axle 1 measuring lateral versine.
Declared= Real*4    Default= -2.

AXLEPOS_VERSINE_2
Longitudinal position of counter axle 2 measuring lateral versine.
Declared= Real*4    Default= 3.

ICOL_KM
The number of the kilometer column.
Declared= Integer*4    Default= 0

ICOL_M
The number of the meter column.
Declared= Integer*4    Default= 0

ICOL_VERTL
The number of the vertical left rail column.
Declared= Integer*4    Default= 0

ICOL_VERTR
The number of the vertical right rail column.
Declared= Integer*4    Default= 0

ICOL_CANT
The number of cant column.
Declared= Integer*4    Default= 0

ICOL_LATL
The number of the lateral left rail column.
Declared= Integer*4    Default= 0

ICOL_LATR
The number of the lateral right rail column.
Declared= Integer*4    Default= 0

ICOL_GAUGE
The number of gauge column.
Declared= Integer*4    Default= 0

SCALE_VERTL
The number of the vertical left rail column.
Declared= Real*4    Default= 1.

SCALE_VERTR
The number of the vertical right rail column.
Declared= Real*4    Default= 1.

SCALE_CANT
The number of cant column.
Declared= Real*4    Default= 1.

SCALE_LATL
The number of the lateral left rail column.
Declared= Real*4    Default= 1.

SCALE_LATR
The number of the lateral right rail column.
Declared= Real*4    Default= 1.

SCALE_GAUGE
The number of gauge column.
Declared= Real*4    Default= 1.


Input data Example

Following example: Master.trc_iplas4f can be used as a master file:


##
##   Input data for program "trc_iplas4"
##

  VEHICLE_DIRECTION= A    # I.e. The right side of the measuring vehicle is to the right side of the track,
                          # when looking towards increasing kilometer poles

  L_SHORT_WAVES= 1.5      # Lowpass filter cutoff wave length
  N_SHORT_WAVES= 8        # Order of the lowpass filter

  L_LATERAL_WAVES= 55.55  # Highpass filter cutoff wave length
  N_LATERAL_WAVES= 6      # Order of the lowpass filter

  XSTART_KM= 25  XSTART_M= 400  # Select track section to translate
  XSTOP_KM = 35  XSTOP_M = 400  # 

  INFIL= 913011_Jan06.prn
  UTFIL= 913011_Jan06.trax_wdesign

  ncols= 9              # Number of columns in INFIL
  dx= 0.5               # Equidistant X-spacing between lines in UTFIL

#
# Relative positions of the wheelsets in the vehicle
# These distances are valid for VEHICLE_DIRECTION= A
# For VEHICLE_DIRECTION= B the opposite will apply
# --------------------------------------------------
  AXLEPOS_CANT = 0.         # Position of the wheelset measuring cant
  AXLEPOS_GAUGE= 0.         # Position of the wheelset measuring gauge
  AXLEPOS_LEVEL  =  0.      # Position of the wheelset measuring vertical level
  AXLEPOS_LEVEL_1= -2.      # Position of the counter axle 1 measuring vertical level
  AXLEPOS_LEVEL_2=  3.      # Position of the counter axle 2 measuring vertical level
  AXLEPOS_VERSINE  =  0.    # Position of the wheelset measuring horizontal versine
  AXLEPOS_VERSINE_1= -5.    # Position of the counter axle 1 measuring horizontal versine
  AXLEPOS_VERSINE_2=  5.    # Position of the counter axle 2 measuring horizontal versine

#
# Column numbers read from INFILE
# -------------------------------
  icol_km= 1                # Kilometer
  icol_m = 2                # Meter
  icol_vertl= 4             # Vertical left rail
  icol_vertr= 3             # Vertical right rail
  icol_cant = 5             # Cant
  icol_latl = 8             # Lateral left rail
  icol_latr = 7             # Lateral right rail
  icol_gauge= 9             # Gauge

#
# Scale factors
# -------------
  scale_vertl=    1         # Vertical left rail
  scale_vertr=    1         # Vertical right rail
  scale_cant =    1         # Cant
  scale_latl =    1         # Lateral left rail
  scale_latr =    1         # Lateral right rail
  scale_gauge=    1         # Gauge