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Commit 07c385da authored by Markus Quaritsch's avatar Markus Quaritsch
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update documentation on new coasting model and new shift strategy

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......@@ -64,6 +64,17 @@ Use the ![add](pics/plus-circle-icon.png) and ![remove](pics/minus-circle-icon.p
![](pics/checkbox.png) Skip Gears
: See [Gear Shift Model](#gear-shift-model).
<div class="vecto3">
Since version Vecto 3.0.3 the gearshift polygon calculation according to the ACEA White Book 2016 is implemented and since Vecto 3.0.4 the ACEA White Book 2016 shift strategy for AMT and MT is implemented. For details on this topic please see the ACEA White Book 2016.
The user interface contains input fields for the following parameters:
! - **Downshift after upshift delay**: to prevent frequent (oscilating) up-/down shifts this parameter blocks downshifts for a certain period after an upshift
- **Upshift after downshift delay**: to prevent frequent (oscilating) up-/down shifts this parameter blocks upshifts for a certain period after a downshift
- **Min acceleration after upshift**: after an upshift the vehicle must be able to accelerate with at least the given acceleration. The achievable acceleration after an upshift is estimated on the current driving condition and powertrain state.
![](pics/Vecto_ShiftStrategyParameters.png)
</div>
Torque Reserve \[%\]
: This parameter is required for the **Allow shift-up inside polygons** and **Skip Gears** options.
......
##Look-Ahead Coasting
Like Overspeed, Look-Ahead Coasting is a function that aims on modelling real-life driver behaviour. It is a forward-looking function that detects forthcoming reductions in target speed in the mission profile (e.g. speed limit, etc.) and induces an early deceleration using engine braking before applying mechanical brakes according to the [deceleration limit](#acceleration-limiting).
The implemented approach uses a predefined target deceleration (a~lookahead~) to calculate the deceleration time for each particular target speed change.
......@@ -10,6 +9,74 @@ Like Overspeed, Look-Ahead Coasting is a function that aims on modelling real-li
At the resulting deceleration start point the model calculates the
coasting trajectory until it meets the brake deceleration trajectory. The resulting deceleration consists of a coasting phase followed by combined mechanical/engine braking. If Look-Ahead Coasting is disabled only the braking phase according to the [deceleration limit](#acceleration-limiting) will be applied.
<div class="vecto3">
Since Vecto 3.0.4 the coasting strategy according to the ACEA White Book 2016 is implemented.
The look ahead coasting functionality represents the driver behavior prior to a deceleration event. Due to information of the route ahead the driver is able to anticipate on the deceleration event by releasing the accelerator pedal.
This pedal release decision is based on an estimation of kinetical and potential (height) energy gain versus the expected dissipated energy tue to vehicle resistances during the route section ahead.
For an upcoming target speed change the energy level after the speed change is compared to the vehicle's current energy level (kinetic and potential energy). The difference of those energy levels is used to estimate the average deceleration force to reach the next target speed. Coasting starts if the vehicle's (estimated) average resistance force during coasting multiplied by a speed dependent 'Decision Factor' becomes smaller than the average deceleration force. (For details on the equations please see the ACEA White Book 2016, Section 8)
The *Decision Factor (DF)* depends on the next target speed and the speed change:
$DF_{Coasting} = 2.5 - 1.5 * DF_{vel} * DF_{vdrop}$
whereas $DF_{vel}$ and $DF_{vdrop}$ are speed dependent and speed change dependent lookup curves, giving a value from 0 and 1.
For the look ahead coasting target speed changes within the preview distance are considered.
$preview distance [m] = 10 * vehicle speed [km/h]$
Parameters in [Job File](#job-file):
: - **PreviewDistanceFactor**
- **DF_offset**: offset in the equation for DF~coasting~ (default 2.5)
- **DF_scaling**: factor in the equation for DF~coasting~ (default 1.5)
- **DF_targetSpeedLookup**: csv file for DF~vel~ lookup (see below)
- **Df_velocityDropLookup**: csv file for DF~vdrop~ lookup (see below)
In engineering mode the parameters can be freely chosen while in declaration mode the default values are used.
![](pics/Vecto-UI_LAC.png)
####Decision Factor for target velocity lookup (DF~vel~)
![](pics/Vecto_LAC-DF.png)
Example (default values):
~~~
v_target [km/h], decision_factor [-]
0 , 0
48 , 0
52 , 1
100 , 1
~~~
####Decision Factor for velocity drop lookup (DF~vdrop~)
Example (default values):
~~~
v_drop [km/h], decision_factor [-]
-100 , 1
9 , 1
11 , 0
100 , 0
~~~
</div>
<div class="vecto2">
The implemented approach uses a predefined target deceleration (a~lookahead~) to calculate the deceleration time for each particular target speed change.
![](pics/LAC.svg)
At the resulting deceleration start point the model calculates the
coasting trajectory until it meets the brake deceleration trajectory. The resulting deceleration consists of a coasting phase followed by combined mechanical/engine braking. If Look-Ahead Coasting is disabled only the braking phase according to the [deceleration limit](#acceleration-limiting) will be applied.
Parameters in [Job File](#job-file):
: - **Target Retardation** = a~lookahead~
- **Minimum speed**. Below this speed the function is disabled.
</div>
......@@ -44,3 +44,15 @@ Early Upshift can be enabled in the [Gearbox File](#gearbox-file) (Allow shift-u
![](pics/GBX-Editor-shift2.svg)
###Generic shift conditions (extra conditions)
- Only allow upshifts if the vehicle is not decelerating **and** the calculated (estimated) acceleration in the next gear is higher than a certain value (default: 0.1 m/s²)
- Do not allow downshifts with less time than a certain amount after an upshift (default 10 s)
- Do not allow upshifts with less time than a certain amount after an downshift (default 10 s)
Parameters in [Gearbox File](#gearbox-file):
: - **DownshiftAferUpshiftDelay**
- **UpshiftAfterDownshiftDelay**
- **UpshiftMinAcceleration**
......@@ -104,6 +104,9 @@ Refers to other files:
"RefRPM": 0.0,
"Inertia": 0.0
}
"DownshiftAferUpshiftDelay": 10.0,
"UpshiftAfterDownshiftDelay": 10.0,
"UpshiftMinAcceleration": 0.1
}
}
~~~
......
#Changelog
**VECTO 3.0.4**
***Build 544 (2016-06-28)***
- Main Updates
+ New gear shift strategy according to White Book 2016
+ New coasting strategy according to White Book 2016
+ New input parameters (enineering mode) for coasting and gear shift behavior
+ Use SI units in Advanced Auxiliaries Module and compile with strict compiler settings (no implicit casts, etc.)
+ Allow efficiency for transmission losses (in engineering mode)
- Bugfixes
+ Auxiliary TechList not read from JSON input data
+ Improvements in driver strategy
+ Bugfixes in MeasuredSpeed mode
**VECTO 3.0.3**
***Build 537 (2016-06-21)***
......
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Documentation/User Manual/pics/Vecto-UI_LAC.PNG

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Documentation/User Manual/pics/Vecto_LAC-DF.PNG

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Documentation/User Manual/pics/Vecto_ShiftStrategyParameters.PNG

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