Reference

PhysicsTrackJoint

A custom joint for the PhysX engine that keeps a wheel frame on a track.

\	PhysicsTrackJoint
Inherits:	PhysicsJoint

Body 0

Relationship to any UsdGeomXformable.

\	physics:body0
Type:	Relationship

Break Force

Joint break force. If set, joint is to break when this force limit is reached. (Used for linear dofs.)

\	physics:breakForce
Type:	float
Dimension:	mass * distance / time / time
Units:	inherited from mass, distance, time
Range:	[0,inf]
Default Value:	inf

Break Torque

Joint break torque. If set, joint is to break when this torque limit is reached. (Used for angular dofs.)

\	physics:breakTorque
Type:	float
Dimension:	mass * distance * distance / time / time
Units:	inherited from mass, distance, time
Range:	[0,inf]
Default Value:	inf

Collision Enabled

Determines if the jointed subtrees should collide or not.

\	physics:collisionEnabled
Type:	bool
Dimension:	One
Range:	0,1
Default Value:	0

Exclude From Articulation

Determines if the joint can be included in an Articulation.

\	physics:excludeFromArticulation
Type:	bool
Dimension:	One
Range:	0,1
Default Value:	0

Joint Enabled

Determines if the joint is enabled.

\	physics:jointEnabled
Type:	bool
Dimension:	One
Range:	0,1
Default Value:	1

Local Position 0

Relative position of the joint frame to body0's frame.

\	physics:localPos0
Type:	point3f
Dimension:	distance
Default Units:	inherited
Range:	]-inf,+inf[
Default Value:	(0, 0, 0)

Local Rotation 0

Relative orientation of the joint frame to body0's frame.

\	physics:localRot0
Type:	quatf

Dimension: | Default Units:| Range: | Default Value:| (1, 0, 0, 0)

Force Limit Normal Min

Minimum force to be applied along the direction orthogonal to the track. Overrides physics:breakForce if authored.

\	physics:normalForceLimitsMin
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[-inf,0kN]
Default Value:	-inf

Force Limit Normal Max

Maximum force to be applied along the direction orthogonal to the track. Overrides physics:breakForce if authored.

\	physics:normalForceLimitsMax
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[0kN,+inf]
Default Value:	+inf

Torque Limit along Normal

Maximum torque to be applied along the direction orthogonal to the track. Overrides physics:breakTorque if authored.

\	physics:normalTorqueLimit
Type:	Dimensionated Value
Dimension:	mass * distance * distance / time / time
Default Units:	kNm
Range:	[0kNm,+inf]
Default Value:	+inf

Force Limit Binormal Min

Minimum force to be applied along the direction perpendicular to the track. Overrides physics:breakForce if authored.

\	physics:binormalForceLimitsMin
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[-inf,0kN]
Default Value:	0kN

Force Limit Binormal Max

Maximum force to be applied along the direction perpendicular to the track. Overrides physics:breakForce if authored.

\	physics:binormalForceLimitsMax
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[0kN,+inf]
Default Value:	+inf

Torque Limit along Tangent and Binormal

Maximum torque to be applied along the direction along as well as perpendicular to the track. Overrides physics:breakForce if authored.

\	physics:torqueLimit
Type:	Dimensionated Value
Dimension:	mass * distance * distance / time / time
Default Units:	kNm
Range:	[0kNm,+inf]
Default Value:	+inf

Force Limit Motor Min

Minimum and maximum force to be applied by the motor to reach the target velocity.

\	physics:motorForceLimitsMin
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[-inf,0kN]
Default Value:	0kN

Force Limit Motor Max

Minimum and maximum force to be applied by the motor to reach the target velocity.

\	physics:motorForceLimitsMax
Type:	Dimensionated Value
Dimension:	mass * distance / time / time
Default Units:	kN
Range:	[0kN,+inf]
Default Value:	0kN

Target Velocity

The target velocity along the track a motor aims for.

\	physics:motorTargetVelocity
Type:	Dimensionated Value
Dimension:	distance / time
Default Units:	km/h
Range:	[-inf,+inf]
Default Value:	0m/s

Threshold for Position

A positional error in the alignemt of the anchor to the track that would lead to derailment.

\	physics:thresholdPosition
Type:	Dimensionated Value
Dimension:	distance
Default Units:	m
Range:	]0m,+inf]
Default Value:	35cm

Threshold for Tangent

A rotational error in the alignemt of the anchor to the track that would lead to derailment.

\	physics:thresholdTangent
Type:	float
Dimension:	One
Units:	degree
Range:	]0,90]
Default Value:	45

Threshold for Normal

A rotational error in the alignemt of the anchor to the track that would lead to derailment.

\	physics:thresholdNormal
Type:	float
Dimension:	One
Units:	degree
Range:	]0,90]
Default Value:	45

Threshold for Binormal

A rotational error in the alignemt of the anchor to the track that would lead to derailment.

\	physics:thresholdBinormal
Type:	Dimensionated Value
Dimension:	One
Units:	degree
Range:	]0,90]
Default Value:	45

Flange

The hight of the wheels flange, if any.

\	physics:flange
Type:	Dimensionated Value
Dimension:	distance
Default Units:	m
Range:	[0m,+inf]
Default Value:	+inf

Track System

Reference to a track system to rail the trackjoint on. A track system is a prim that contains any 'TSTrack' prims.

\	physics:trackSystem
Type:	Relationship

PhysicsTractionForceCharacteristic

Function that defines the characteristic behaviour of a engine-gear unit to change its maximum available traction force with velocity.

\	PhysicsTractionForceCharacteristic
Inherits:	Typed

Speed Steps

List of speed steps in the charactersitic.

\	physics:speedSteps
Type:	float2[]
Dimension:	(distance / time, One)
Units:	(cm/s,1)
Range:	([0,+inf], [0,1])

PhysicsWheelFrame

A wheel frame holds a track joint and wheesets - makes up a model for friction, brake and motor. Add a PhysicsTrackJoint as child prim in order to establish a connection to a track system. Add some PhysicsWheelset as child prim to define the maximum drive, braking and friction forces, the track joint can apply. A PhysicsTractionForceCharacteristic helps to shape a model of the engine-gear unit of a rolling stock.

\	PhysicsWheelFrame
Inherits:	Typed

Brake

Sets the fraction of the maximum braking to apply in order to reach a zero velocity.

\	physics:brake
Type:	Dimensionated Value
Dimension:	One
Range:	[0,1]
Default Value:	0

Target Velocity

The target velocity along the track a motor aims for.

\	physics:targetVelocity
Type:	Dimensionated Value
Dimension:	distance / time
Default Units:	km/h
Range:	[-inf,+inf]
Default Value:	0m/s

Thrust

Sets the fraction of the maximum thrust to apply in order to reach the target velocity specified by TargetVelocity().

\	physics:thrust
Type:	Dimensionated Value
Dimension:	One
Range:	[0,1]
Default Value:	0

Traction Force Characteristic

Reference to a PhysicsTractionForceCharacteristic.

\	physics:tractionForceCharacteristic
Type:	Relationship

PhysicsWheelset

A wheelset is an axle with two wheels attached to it. The PhysicsWheelset child prim adds to it's parent's PhysicsWheelFrame motor forces.

\	PhysicsWheelset
Inherits:	Typed

Friction Torque

Friction that is introduced by this wheel.

\	physics:frictionTorque
Type:	Dimensionated Value
Dimension:	mass * distance * distance / time / time
Default Units:	kNm
Range:	[0kNm,+inf]
Default Value:	0kNm

Maximum Braking Torque

Maximum braking torque that this wheelset can apply.

\	physics:maxBrakingTorque
Type:	Dimensionated Value
Dimension:	mass * distance * distance / time / time
Default Units:	kNm
Range:	[0kNm,+inf]
Default Value:	0kNm

Maximum Motor Torque

Maximum torque that this wheelset can apply for acceleration.

\	physics:maxMotorTorque
Type:	Dimensionated Value
Dimension:	mass * distance * distance / time / time
Default Units:	kNm
Range:	[0kNm,+inf]
Default Value:	0kNm

Radius

Radius of wheel from center of axle to contact surface with rods.

\	physics:radius
Type:	Dimensionated Value
Dimension:	distance
Default Units:	m
Range:	]0m,+inf[
Default Value:	50cm

TSTrack

Describes a track for a track joint to ride on. A track's geometry is defined by a curve, a twist and a general transforamtion. The latter is define by the xformOp operations. The track specifies for it's ends to be connected with other track's ends.

\	TSTrack
Inherits:	Xformable
Parent Prim:	TSTrackCollection, TSTrackSystem

curve

Reference to a Bezier BasisCurves to define the geometry of the track.

\	curve
Type:	Dimensionated Value
Dimension:	Relationship

intervalNear

The location along the curve to start the track with.

\	intervalNear
Type:	Dimensionated Value
Dimension:	distance
Default Units:	m
Range:	]-inf,+inf[
Default Value:	0m

intervalFar

The location along the curve to end the track with.

\	intervalFar
Type:	Dimensionated Value
Dimension:	distance
Default Units:	m
Range:	[-inf,+inf]
Default Value:	+inf

frontConnection

Reference to a TSTrack that should be coupled with the front end of this track.

\	frontConnection
Type:	Relationship

frontConnectionEndType

End of referenced TSTrack to couple the front end of this track to.

\	frontConnectionEndType
Type:	token
allowedTokens:	["front", "end"]

endConnection

Reference to a TSTrack that should be coupled with the end end of this track.

\	endConnection
Type:	Relationship

endConnectionEndType

End of referenced TSTrack to couple the end end of this track to.

\	endConnectionEndType
Type:	token
allowedTokens:	["front", "end"]

trackBody

Reference to a physics and mass enabled body. This track will move with the body in the simulation.

\	trackBody
Type:	Relationship

TSConnectorCollection

A connector collection is a prim that contains connectors (i.e. switches). It is used to group track connectors together.

\	TSConnectorCollection
Inherits:	Scope
Parent Prim:	TSTrackSystem

TSTrackCollection

A track collection is a prim that contains any 'TSTrack' prims. It is used to group tracks together.

\	TSTrackCollection
Inherits:	Xformable
Parent Prim:	TSTrackSystem

TSTrackSystem

A track system is a prim that contains any 'TSTrackCollection' prims. It is used to group track collections and switches together and to provide a reference for track joints to rail on.

\	TSTrackSystem
Inherits:	Scope

metersPerUnit

The conversion factor from the units of the TrackCollections' and Tracks' Xform attributes to meters, when interpreted by the trax library. The trax system works with fixed units; this is no problem in a single USD file with its 'metersPerUnit' metadata properly set. However, if layers or references are used, the 'metersPerUnit' metadata in a given USD file is no longer respected. The lengthes of USD attributes get reinterpreted by the 'metersPerUnit' metadata of the stage. For religious reasons we don't believe in such a thing as a 'scaled meter', hence we need to carry the proper scaling factor with us.

\	Meters Per Unit
Type:	double
Dimension:	distance
Range:	]0,+inf[
Default Value:	1.0

TS2WaySwitch

A two way switch reconnects three track ends according to the switches state.

\	TS2WaySwitch
Inherits:	Typed
Parent Prim:	TSConnectorCollection

divergingTrack

The track to connect with the incomming track at state 'branch'.

\	divergingTrack
Type:	Relationship

divergingTrackEndType

The end of the diverging track to connect.

\	divergingTrackEndType
Type:	token
allowedTokens:	["front", "end"]

id

A unique id for sthe switch, to reference it. If 0, the switch gets assigned an id automatically.

\	id
Type:	int
Dimension:	One
Range:	[0,+inf[
Default Value:	0

narrowTrack

Reference to the incoming track of the switch.

\	narrowTrack
Type:	Relationship

narrowTrackEndType

End of the incoming track to connect.

\	narrowTrackEndType
Type:	token
allowedTokens:	["front", "end"]

Default Units:|

state

The state of the switch.

\	state
Type:	token
allowedTokens:	["go", "branch"]

straightTrack

The track to connect with the incomming track at state 'go'.

\	straightTrack
Type:	Relationship

straightTrackEndType

The end of the straight track to connect.

\	straightTrackEndType
Type:	Dimensionated Value
allowedTokens:	["front", "end"]

TS3WaySwitch

A three way switch reconnects four track ends according to the switches state.

\	TS3WaySwitch
Inherits:	Typed
Parent Prim:	TSConnectorCollection

divergingTrack1

The track to connect with the incomming track at state 'branch1'.

\	divergingTrack1
Type:	Relationship

divergingTrack1EndType

The end of the diverging track1 to connect.

\	divergingTrack1EndType
Type:	token
allowedTokens:	["front", "end"]

divergingTrack2

The track to connect with the incomming track at state 'branch2'.

\	divergingTrack2
Type:	Relationship

divergingTrack2EndType

The end of the diverging track2 to connect.

\	divergingTrack2EndType
Type:	token
allowedTokens:	["front", "end"]

id

A unique id for sthe switch, to reference it. If 0, the switch gets assigned an id automatically.

\	id
Type:	int
Dimension:	One
Range:	[0,+inf[
Default Value:	0

narrowTrack

Reference to the incoming track of the switch.

\	narrowTrack
Type:	Relationship

narrowTrackEndType

End of the incoming track to connect.

\	narrowTrackEndType
Type:	token
allowedTokens:	["front", "end"]

state

The state of the switch.

\	state
Type:	token
allowedTokens:	["go", "branch", "branch1", "branch2"]

straightTrack

The track to connect with the incomming track at state 'go'.

\	straightTrack
Type:	Relationship

straightTrackEndType

The end of the straight track to connect.

\	straightTrackEndType
Type:	token
allowedTokens:	["front", "end"]

TS1SlipSwitch

A single slip switch consisting of two incoming '','/' and two outgoing tracks 'X' - the outgoing tracks are expected to cross each other - and a diverging track ')'.

\
)X
/ 

\	TS1SlipSwitch
Inherits:	Typed
Parent Prim:	TSConnectorCollection

id

A unique id for sthe switch, to reference it. If 0, the switch gets assigned an id automatically.

\	id
Type:	int
Dimension:	One
Range:	[0,+inf[
Default Value:	0

incomingTrack1

Reference to first incoming track.

\	incomingTrack1
Type:	Relationship

incomingTrack1EndType

End of track referenced for first incoming track.

\	incomingTrack1EndType
Type:	token
allowedTokens:	["front", "end"]

incomingTrack2

Reference to second incoming track.

\	incomingTrack2
Type:	Relationship

incomingTrack2EndType

End of track referenced for second incoming track.

\	incomingTrack2EndType
Type:	token
allowedTokens:	["front", "end"]

outgoingTrack1

Reference to first outgoing track.

\	outgoingTrack1
Type:	Relationship

outgoingTrack1EndType

End of track referenced for first outgoing track.

\	outgoingTrack1EndType
Type:	token
allowedTokens:	["front", "end"]

outgoingTrack2

Reference to second outgoing track.

\	outgoingTrack2
Type:	Relationship

outgoingTrack2EndType

End of track referenced for second outgoing track.

\	outgoingTrack2EndType
Type:	token
allowedTokens:	["front", "end"]

state

The state of the switch.

\	state
Type:	token
allowedTokens:	["go", "branch"]

track1Diverge

Reference to first diverging track.

\	track1Diverge
Type:	Relationship

track1DivergeIncomingEndType

End of track referenced for first diverging track.

\	track1DivergeIncomingEndType
Type:	token
allowedTokens:	["front", "end"]

TS2SlipSwitch

A double slip switch consisting of two straight tracks 'X', crossing each other; two incoming tracks, two outgoing tracks - all four connecting to the straight track ends - and two diverging tracks ')' and '(', connecting incoming and outgoing tracks:

\ /
)X(
/ \

\	TS2SlipSwitch
Inherits:	Typed
Parent Prim:	TSConnectorCollection

id

\	id
Type:	Dimensionated Value
Dimension:	One
Range:	[0,+inf[
Default Value:	0

incomingTrack1

Reference to first incoming track.

\	incomingTrack1
Type:	Relationship

incomingTrack1EndType

End of track referenced for first incoming track.

\	incomingTrack1EndType
Type:	token
allowedTokens:	["front", "end"]

incomingTrack2

Reference to second incoming track.

\	incomingTrack2
Type:	Relationship

incomingTrack2EndType

End of track referenced for second incoming track.

\	incomingTrack2EndType
Type:	token
allowedTokens:	["front", "end"]

outgoingTrack1

Reference to first outgoing track.

\	outgoingTrack1
Type:	Relationship

outgoingTrack1EndType

End of track referenced for first outgoing track.

\	outgoingTrack1EndType
Type:	token
allowedTokens:	["front", "end"]

outgoingTrack2

Reference to second outgoing track.

\	outgoingTrack2
Type:	Relationship

outgoingTrack2EndType

End of track referenced for second outgoing track.

\	outgoingTrack2EndType
Type:	token
allowedTokens:	["front", "end"]

state

The state of the switch.

\	state
Type:	token
allowedTokens:	["go", "branch", "branch1", "branch2"]

track1Diverge

Reference to first diverging track.

\	track1Diverge
Type:	Relationship

track1DivergeIncomingEndType

End of track referenced for first diverging track.

\	track1DivergeIncomingEndType
Type:	token
allowedTokens:	["front", "end"]

track1Straight

Reference to first straight track.

\	track1Straight
Type:	Relationship

track1StraightIncomingEndType

End of track referenced for first straight track.

\	track1StraightIncomingEndType
Type:	token
allowedTokens:	["front", "end"]

track2Diverge

Reference to second diverging track.

\	track2Diverge
Type:	Relationship

track2DivergeIncomingEndType

End of track referenced for second diverging track.

\	track2DivergeIncomingEndType
Type:	token
allowedTokens:	["front", "end"]

track2Straight

Reference to second straight track.

\	track2Straight
Type:	Relationship

track2StraightIncomingEndType

End of track referenced for second straight track.

\	track2StraightIncomingEndType
Type:	token
allowedTokens:	["front", "end"]