trax::TractionForceCharacteristic Struct Reference

Function that defines the characteristic behaviour of a motor to change its maximum available tracktion force with velocity. More...

#include <C:/Trend/Development/Trax3/Code/trax/rigid/TractionForceCharacteristic.h>

Public Types
enum class	TractionType : char {   unknown = 0 , mechanic , hydrodynamic , electric ,   steam , speedsteps , other }
	Some exemplaric traction types. More...

Public Member Functions
virtual TractionType	GetTractionType () const noexcept=0
virtual One	operator() (Velocity velocity) const noexcept=0
	Mapping function.
virtual decltype(Power{}/Force{})	MaximumPowerFraction () const noexcept=0
virtual Velocity	MaximumVelocity () const noexcept=0
virtual void	AddSpeedStep (Velocity velocity, One value)=0
	Add a velocity/value pair to the characteristic.
virtual void	GetSpeedSteps (std::vector< std::pair< Velocity, One > > &speedsteps) const =0
	Get all the speedsteps.
	TractionForceCharacteristic (const TractionForceCharacteristic &)=delete
	TractionForceCharacteristic (TractionForceCharacteristic &&)=delete
TractionForceCharacteristic &	operator= (const TractionForceCharacteristic &)=delete
TractionForceCharacteristic &	operator= (TractionForceCharacteristic &&)=delete

Static Public Member Functions
static dclspc std::unique_ptr< TractionForceCharacteristic >	Make (TractionType type=TractionType::speedsteps, Velocity vmax=0_mIs, Velocity vtransit=0_mIs) noexcept

Detailed Description

Function that defines the characteristic behaviour of a motor to change its maximum available tracktion force with velocity.

The Factory provides one sample implementation for each TractionType. These are:

/// mechanic:
/// f = fstep for vstep <= v < vnextstep
///
/// hydrodynamic:
/// f = fstep + (fnextstep - fstep) (v - vstep)/(vnextstep - vstep)  for vstep <= v < vnextstep
///
/// electric:
/// f = a/(v+x) - y
/// with:
/// x = sqrt( (vm-vt)(a + (vm-vt)/4) ) - (vm+vt)/2 with vt < vm
/// y = a / (vm+x)
/// f = a(vm-v)/(v+x)(vm+x)
///
/// steam:
/// as electric with vt = 0
/// 

Member Enumeration Documentation

TractionType

enum class trax::TractionForceCharacteristic::TractionType : char

strong

Some exemplaric traction types.

Enumerator
mechanic	mechanical gear with different discrete gear settings
hydrodynamic	continuous linear gear settings
electric	constant traction force followed by hyperbolic decline
steam	hyperbolic decline from the start

Member Function Documentation

MaximumPowerFraction()

virtual decltype(Power{}/Force{}) trax::TractionForceCharacteristic::MaximumPowerFraction ( ) const

pure virtualnoexcept

Returns

The maximum power the engine can develop with the characteristic divided by the maximum traction force (just multiply with max force to yield power)

MaximumVelocity()

virtual Velocity trax::TractionForceCharacteristic::MaximumVelocity ( ) const

pure virtualnoexcept

Returns

The maximum velocity the engine can theoretically achieve under the assumtion that no work has to be done by her.

operator()()

virtual One trax::TractionForceCharacteristic::operator() ( Velocity velocity ) const

pure virtualnoexcept

Mapping function.

The characteristic gets multiplied with the maximum torque. A value of 1 means that the maximum torques are applied as specified by the Wheelsets attached to a WheelFrame. Typically the value will drop linearly or hyperbolically if the absolute value of velocity gets high; it might get even negative at some extreme point.

Parameters

velocity

Velocity along the track.

Returns

Factor in the range [-1,1].

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The documentation for this struct was generated from the following file:

• C:/Trend/Development/Trax3/Code/trax/rigid/TractionForceCharacteristic.h