309
edits
Changes
Jump to navigation
Jump to search
New documentation for the accessory_engine_data unit. SCS guys please double-check adblue_consumption. ;)
The '''accessory_engine_data''' unit type is used to define the engine characteristics for the player's vehicle, as well as some upshift and downshift characteristics for automatic transmission gameplay.
== Attributes ==
Many common attributes are inherited from [[Documentation/Engine/Units/accessory_data|'''accessory_data''']].
{|class="wikitable"
!Name
![[Documentation/Engine/Units#Attribute_types|Type]]
!Required/Optional
!Description
|-
|info
|string array
|optional
|Three '''info''' members are usually defined for '''accessory_engine_data'''.
<syntaxhighlight lang="cpp">
info[]: "197 @@hp@@ (147@@kw@@)" // The first is the rated power
info[]: "550 @@lb_ft@@ (782 @@nm@@)" // The second is the peak torque
info[]: "1@@dg@@200 @@rpm@@" // The third is the peak torque speed
</syntaxhighlight>
{{Note|The info attribute has no effect on the engine simulation. Rather, it is used for UI display and for attaching to World of Trucks profile truck uploads.}}
|-
|torque
|float
|required
|This defines the maximum torque output of the engine in N·m.
|-
|torque_curve
|float2 array
|optional
|This defines the torque output of the engine at various engine speeds, relative to the maximum torque defined in '''torque'''. For example:
<syntaxhighlight lang="cpp">
torque: 745.7 // 550 lb-ft
// Detroit Diesel Curve E4-1061-52-20
torque_curve[]: (300, 0)
torque_curve[]: (440, 0.5) // Fiddling with the output around 440 rpm will influence how easily the engine stalls when clutching.
torque_curve[]: (800, 0.96) // 528 lb-ft at 800 rpm
torque_curve[]: (1200, 1) // 550 lb-ft at 1200 rpm (peak torque)
torque_curve[]: (1400, 0.99)
torque_curve[]: (1600, 0.97)
torque_curve[]: (1800, 0.45)
torque_curve[]: (2000, 0.91)
torque_curve[]: (2100, 0.89) // 489.5 lb-ft at 2100 rpm (197 hp, rated power)
torque_curve[]: (2300, 0) // High idle (0hp) at 2300 rpm
</syntaxhighlight>
The torque output is linearly interpolated between data points. For engine speeds outside the domain of the data points, the output is clamped to the values at the highest/lowest rpm points. The valid range for torque output is 0-1.
|-
|rpm_idle
|float
|required
|This is the engine speed the virtual engine controller will attempt to maintain with no throttle input.
|-
|rpm_limit
|float
|required
|This is the maximum engine speed the virtual engine controller will allow (except if the engine is being driven by the wheels).
|-
|rpm_limit_neutral
|float
|optional
|This is the maximum engine speed the virtual engine controller will allow if the transmission is in neutral. If unset, this defaults to '''rpm_limit'''.
|-
|rpm_range_low_gear
|float2
|required
|Defines the downshift and upshift engine speeds in low-range gears.
|-
|rpm_range_high_gear
|float2
|required
|Defines the downshift and upshift engine speeds in high-range gears.
|-
|rpm_range_engine_brake
|float2
|optional
|Defines the downshift and upshift engine speeds while the engine brake is operating.
|-
|rpm_range_power_boost
|float2
|optional
|Defines the ''change'' to '''rpm_range_low_gear''' and '''rpm_range_high_gear''' at full throttle when adaptive automatic transmission is enabled.
|-
|engine_brake
|float
|optional
|Peak engine braking torque relative to '''torque''', at the maximum engine brake strength.
|-
|engine_brake_downshift
|bool
|optional
|When true, automatic transmissions will downshift upon beginning engine brake behavior as long as '''rpm_limit''' is not exceeded. Defaults to false.
|-
|engine_brake_positions
|uint
|optional
|Defines the number of strength levels for the engine brake. The braking torque at each position is based linearly on the number of positions. So for <code>engine_brake_positions: 3</code> the first position will have <sup>1</sup>⁄<sub>3</sub> × '''engine_brake''' × '''torque''', the second position will have <sup>2</sup>⁄<sub>3</sub> × '''engine_brake''' × '''torque''', and the highest position will have '''engine_brake''' × '''torque'''.
|-
|volume
|float
|required
|The (four-stroke) volumetric displacement of the engine in liters. It is used in fuel consumption calculations. {{Note|For two-stroke diesel engines, this should be roughly twice the swept volume.}}
|-
|consumption_coef
|float
|optional
|This is used to scale the fuel consumption of the engine relative to the game's calculated value.
|-
|adblue_consumption
|float
|optional
|This is used to scale the engine's consumption of AdBlue (Diesel Exhaust Fluid) relative to the game's default.
|-
|no_adblue_power_limit
|float
|optional
|When the AdBlue tank is empty, the engine's power is scaled by this factor.
|}
== Relevant Unit Conversions and Formulas ==
=== Cubic Inches to Liters ===
1 cu·in = 0.0164 L
=== Pound-Feet to Newton-Meters ===
1 lb<sub>f</sub>·ft = 1.3558 N·m
=== Horsepower to Kilowatts ===
1 hp = 0.7457 kW
=== Torque from Power and Speed (Metric Units) ===
T [N·m] = ( P [kW] × 9549 ) ÷ N [RPM]
=== Torque from Power and Speed (English Units) ===
T [lb<sub>f</sub>·ft] = ( P [hp] × 5252 ) ÷ N [RPM]
== Raw Unit Definition ==
<pre style="max-height:300px;overflow:auto"> "accessory_engine_data":{
"superclass":"accessory_data",
"attrs":{
"name":{
"type": "string"
},
"short_name":{
"type": "string"
},
"icon":{
"type": "string"
},
"info":{
"type": "string_array"
},
"price":{
"type": "s64"
},
"unlock":{
"type": "uint"
},
"suitable_for":{
"type": "string_array"
},
"conflict_with":{
"type": "string_array"
},
"defaults":{
"type": "string_array"
},
"require":{
"type": "token_array"
},
"torque":{
"type": "float"
},
"torque_curve":{
"type": "float2_array"
},
"rpm_idle":{
"type": "float"
},
"rpm_limit":{
"type": "float"
},
"rpm_limit_neutral":{
"type": "float"
},
"rpm_range_low_gear":{
"type": "float2"
},
"rpm_range_high_gear":{
"type": "float2"
},
"rpm_range_engine_brake":{
"type": "float2"
},
"rpm_range_power_boost":{
"type": "float2"
},
"engine_brake":{
"type": "float"
},
"engine_brake_downshift":{
"type": "bool"
},
"engine_brake_positions":{
"type": "uint"
},
"volume":{
"type": "float"
},
"consumption_coef":{
"type": "float"
},
"adblue_consumption":{
"type": "float"
},
"no_adblue_power_limit":{
"type": "float"
}
}
},</pre>
== Attributes ==
Many common attributes are inherited from [[Documentation/Engine/Units/accessory_data|'''accessory_data''']].
{|class="wikitable"
!Name
![[Documentation/Engine/Units#Attribute_types|Type]]
!Required/Optional
!Description
|-
|info
|string array
|optional
|Three '''info''' members are usually defined for '''accessory_engine_data'''.
<syntaxhighlight lang="cpp">
info[]: "197 @@hp@@ (147@@kw@@)" // The first is the rated power
info[]: "550 @@lb_ft@@ (782 @@nm@@)" // The second is the peak torque
info[]: "1@@dg@@200 @@rpm@@" // The third is the peak torque speed
</syntaxhighlight>
{{Note|The info attribute has no effect on the engine simulation. Rather, it is used for UI display and for attaching to World of Trucks profile truck uploads.}}
|-
|torque
|float
|required
|This defines the maximum torque output of the engine in N·m.
|-
|torque_curve
|float2 array
|optional
|This defines the torque output of the engine at various engine speeds, relative to the maximum torque defined in '''torque'''. For example:
<syntaxhighlight lang="cpp">
torque: 745.7 // 550 lb-ft
// Detroit Diesel Curve E4-1061-52-20
torque_curve[]: (300, 0)
torque_curve[]: (440, 0.5) // Fiddling with the output around 440 rpm will influence how easily the engine stalls when clutching.
torque_curve[]: (800, 0.96) // 528 lb-ft at 800 rpm
torque_curve[]: (1200, 1) // 550 lb-ft at 1200 rpm (peak torque)
torque_curve[]: (1400, 0.99)
torque_curve[]: (1600, 0.97)
torque_curve[]: (1800, 0.45)
torque_curve[]: (2000, 0.91)
torque_curve[]: (2100, 0.89) // 489.5 lb-ft at 2100 rpm (197 hp, rated power)
torque_curve[]: (2300, 0) // High idle (0hp) at 2300 rpm
</syntaxhighlight>
The torque output is linearly interpolated between data points. For engine speeds outside the domain of the data points, the output is clamped to the values at the highest/lowest rpm points. The valid range for torque output is 0-1.
|-
|rpm_idle
|float
|required
|This is the engine speed the virtual engine controller will attempt to maintain with no throttle input.
|-
|rpm_limit
|float
|required
|This is the maximum engine speed the virtual engine controller will allow (except if the engine is being driven by the wheels).
|-
|rpm_limit_neutral
|float
|optional
|This is the maximum engine speed the virtual engine controller will allow if the transmission is in neutral. If unset, this defaults to '''rpm_limit'''.
|-
|rpm_range_low_gear
|float2
|required
|Defines the downshift and upshift engine speeds in low-range gears.
|-
|rpm_range_high_gear
|float2
|required
|Defines the downshift and upshift engine speeds in high-range gears.
|-
|rpm_range_engine_brake
|float2
|optional
|Defines the downshift and upshift engine speeds while the engine brake is operating.
|-
|rpm_range_power_boost
|float2
|optional
|Defines the ''change'' to '''rpm_range_low_gear''' and '''rpm_range_high_gear''' at full throttle when adaptive automatic transmission is enabled.
|-
|engine_brake
|float
|optional
|Peak engine braking torque relative to '''torque''', at the maximum engine brake strength.
|-
|engine_brake_downshift
|bool
|optional
|When true, automatic transmissions will downshift upon beginning engine brake behavior as long as '''rpm_limit''' is not exceeded. Defaults to false.
|-
|engine_brake_positions
|uint
|optional
|Defines the number of strength levels for the engine brake. The braking torque at each position is based linearly on the number of positions. So for <code>engine_brake_positions: 3</code> the first position will have <sup>1</sup>⁄<sub>3</sub> × '''engine_brake''' × '''torque''', the second position will have <sup>2</sup>⁄<sub>3</sub> × '''engine_brake''' × '''torque''', and the highest position will have '''engine_brake''' × '''torque'''.
|-
|volume
|float
|required
|The (four-stroke) volumetric displacement of the engine in liters. It is used in fuel consumption calculations. {{Note|For two-stroke diesel engines, this should be roughly twice the swept volume.}}
|-
|consumption_coef
|float
|optional
|This is used to scale the fuel consumption of the engine relative to the game's calculated value.
|-
|adblue_consumption
|float
|optional
|This is used to scale the engine's consumption of AdBlue (Diesel Exhaust Fluid) relative to the game's default.
|-
|no_adblue_power_limit
|float
|optional
|When the AdBlue tank is empty, the engine's power is scaled by this factor.
|}
== Relevant Unit Conversions and Formulas ==
=== Cubic Inches to Liters ===
1 cu·in = 0.0164 L
=== Pound-Feet to Newton-Meters ===
1 lb<sub>f</sub>·ft = 1.3558 N·m
=== Horsepower to Kilowatts ===
1 hp = 0.7457 kW
=== Torque from Power and Speed (Metric Units) ===
T [N·m] = ( P [kW] × 9549 ) ÷ N [RPM]
=== Torque from Power and Speed (English Units) ===
T [lb<sub>f</sub>·ft] = ( P [hp] × 5252 ) ÷ N [RPM]
== Raw Unit Definition ==
<pre style="max-height:300px;overflow:auto"> "accessory_engine_data":{
"superclass":"accessory_data",
"attrs":{
"name":{
"type": "string"
},
"short_name":{
"type": "string"
},
"icon":{
"type": "string"
},
"info":{
"type": "string_array"
},
"price":{
"type": "s64"
},
"unlock":{
"type": "uint"
},
"suitable_for":{
"type": "string_array"
},
"conflict_with":{
"type": "string_array"
},
"defaults":{
"type": "string_array"
},
"require":{
"type": "token_array"
},
"torque":{
"type": "float"
},
"torque_curve":{
"type": "float2_array"
},
"rpm_idle":{
"type": "float"
},
"rpm_limit":{
"type": "float"
},
"rpm_limit_neutral":{
"type": "float"
},
"rpm_range_low_gear":{
"type": "float2"
},
"rpm_range_high_gear":{
"type": "float2"
},
"rpm_range_engine_brake":{
"type": "float2"
},
"rpm_range_power_boost":{
"type": "float2"
},
"engine_brake":{
"type": "float"
},
"engine_brake_downshift":{
"type": "bool"
},
"engine_brake_positions":{
"type": "uint"
},
"volume":{
"type": "float"
},
"consumption_coef":{
"type": "float"
},
"adblue_consumption":{
"type": "float"
},
"no_adblue_power_limit":{
"type": "float"
}
}
},</pre>
