VECTO-Logo User Manual JRC-LogoIVT-LogoTUG-Logo

Gearbox Editor

gbx

newNew file
Create a new empty .vgbx file


open Open existing file
Open an existing .vgbx file


save Save current file


SaveAs Save file as...


sendto Send current file to the VECTO Editor
Note: If the current file was opened via the VECTO Editor the file will be sent automatically when saved.


Make and Model
Free text defining the gearbox model, type, etc.


Transmission Type
Depending on the transmission type some options below are not available. The following types are available:
  • Manual Transmission (MT)
    • Activates the "Skip Gears" option. No torque converter.
  • Automated Manual Transmission (AMT)
    • Activates the "Allow shift-up inside polygons" and "Skip Gears" option. No torque converter.
  • Automatic Transmission (AT)
    • Torque converter ist set and must be parameterized.
  • Custom
    • Enables all options for user-defined settings.
Inertia [kgm2]
Rotational inertia of the gearbox (constant for all gears).


Traction Interruption [s]
Interruption during gear shift event.


Gears
  • Doubleclick items to edit ratio and efficiency of the selected gear.
  • Gear "A" defines the ratio of the axle transmission / differential.
  • Gear "TC" (AT only): For AT gearboxes with torque converter a seperate (fictional) gear is defined for cases where the lock-up clutch is open. This gear is used at vehicle start; when the up-shift rpm is reached VECTO will shift to the next gear (Gear 1) which means the lock-up clutch is closed. In the modal result files (.vmod) the "TC" gear will be output as "0.5" (to avoid non-numeric characters).
  • Set ratio=0 for unused gears.
Alternatively to setting a constant efficiency value it is possible to define a Torque Loss Map in the following format:

Torque Loss Map Format (comma-separated, dot = decimal-mark):
c Input Speed* Input Torque* Torque Loss
c [rpm] [Nm] [Nm]
... ... ...
... ... ...
Note: text lines (header, comments, etc.) must start with "c "

*Input Speed & Torque always means engine-side. The Torque Loss Map must include negative torque values for engine motoring operation!

rem Remove Gear


Gear shift parameters

Shift polygons file
(.vgbs)
This file contains the up- and down- shift curves that control the gear shift behaviour. Whenever the actual engine speed crosses the up- or down-shift line a gear-shift is initiated.



Shift Polygons File Format (comma-separated, dot = decimal-mark):
Engine Torque Downshift rpm Upshift rpm
c [Nm] [1/min] [1/min]
... ... ...
... ... ...
Note: text lines (header, comments, etc.) must start with "c "

Open file browser.

Open file with GRAPHi or an user-defined tool (see File Open Command).


Allow shift-up inside polygons
If the next higher gear provides the required torque reserve and it's rpm is still above down-shift-rpm VECTO will shift up.


Skip Gears
Whenever a gear change is initiated (by crossing the up- or down-shift line) VECTO may skip one or several gears as long as the required torque reserve is provided.


Torque Reserve
This parameter is required for the "Allow shift-up inside polygons" and "Skip Gears" options.


Minimum time between two gear shifts
Limits the time between two gear shifts in whole seconds. This rule will be ignored if rpms are too high or too low. Note that high values may cause high rpms during acceleration.


Start Gear
In order to calculate an appropriate gear for vehicle start (first gear after vehicle standstill) a fictional load case is calculated using a specified reference vehicle speed and reference acceleration together with the actual road gradient, transmission losses and auxiliary power demand. This way the start gear is independent from the target speed. VECTO uses the highest possible gear which provides the defined torque reserve.


Torque Converter

The torque converter is defined as (virtual) separate gear, i.e. only first gear with TC active.
While TC active: Iterative calculation of engine torque and speed based on TC characteristic.
Creeping: Engine speed set to idling. Brakes engaged to absorb surplus torque.



Installed
This option is only available if transmission type is set to Custom. For AT this option is always On, for MT and AMT always Off.

Torque converter characteristics file (.vtcc)
This file defines the torque converter characteristics as described in VDI 2153:
Speed Ratio (ν) = Output Speed / Input Speed
Torque Ratio (μ) = Output Torque / Input Torque
Input Torque (Tref(ν)) is the input torque (over ν) for a specific reference engine speed (see below).

The Input Torque at  reference engine speed is needed to needed to calculate the actual engine torque using this formula:

with:
Tin = engine torque [Nm]
Tref(ν) = reference torque at reference rpm (form .vtcc file) [Nm]
nin = engine speed [1/min]
nref = reference rpm [1/min] (see below)

The torque converter characteristics must also be defined for speed ratios of more than one (ν>1) in order to calculate overrun conditions (torque<0).

Torque Loss Map Format (comma-separated, dot = decimal-mark):
Speed Ratio ν Torque Ratio μ Input Torque at reference rpm
c [-] [-] [Nm]
... ... ...
... ... ...
Note: text lines (header, comments, etc.) must start with "c "

Open file browser.

Open file with GRAPHi or an user-defined tool (see File Open Command).


Reference rpm for torque characteristic
Reference engine speed associated with the Input Torque curve in the .vtcc file.

Open file browser.

Open file with GRAPHi or an user-defined tool (see File Open Command).

OKSave and close file
If necessary the file path in the VECTO Editor will be updated.

Cancel Cancel without saving

Contact