LoadTorqueVector

Load with (3D) torque vector; attached to rigidbody-based marker.

Additional information for LoadTorqueVector:

• Requested Marker type = Orientation
• Short name for Python = Torque
• Short name for Python visualization object = VTorque

The item LoadTorqueVector with type = ‘TorqueVector’ has the following parameters:

• name [type = String, default = ‘’]:

  load’s unique name
• markerNumber [type = MarkerIndex, default = invalid (-1)]:

  marker’s number to which load is applied
• loadVector [\(\ttau\), type = Vector3D, default = [0.,0.,0.]]:

  vector-valued load [SI:N]; in case of a user function, this vector is ignored
• bodyFixed [type = Bool, default = False]:

  if bodyFixed is true, the load is defined in body-fixed (local) coordinates, leading to a follower torque; if false: global coordinates are used
• loadVectorUserFunction [\(\mathrm{UF} \in \Rcal^3\), type = PyFunctionVector3DmbsScalarVector3D, default = 0]:

  A Python function which defines the time-dependent load and replaces loadVector; see description below; see also notes on loadFactor and drawing in LoadForceVector! Example for Python function: def f(mbs, t, loadVector): return [loadVector[0]*np.sin(t*10*2*3.1415),0,0]
• visualization [type = VLoadTorqueVector]:

  parameters for visualization of item

The item VLoadTorqueVector has the following parameters:

• show [type = Bool, default = True]:

  set true, if item is shown in visualization and false if it is not shown

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DESCRIPTION of LoadTorqueVector

Details

The torque vector acts on a body or node via the local (bodyFixed = True) or global coordinates of a body or at a node. The marker transforms the torque via the according jacobian matrix of the object (or node) to object (or node) coordinates.

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Userfunction: loadVectorUserFunction(mbs, t, loadVector)

A user function, which computes the torque vector depending on time and object parameters, which is hereafter applied to object or node.

arguments / return	type or size	description
mbs	MainSystem	provides MainSystem mbs to which load belongs
t	Real	current time in mbs
loadVector	Vector3D	\(\ttau\) copied from object; WARNING: this parameter does not work in combination with static computation, as it is changed by the solver over step time
returnValue	Vector3D	computed torque vector

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User function example:

from math import sin, cos, pi
def UFforce(mbs, t, loadVector):
    return [loadVector[0]*sin(t*10*2*pi),0,0]

Relevant Examples and TestModels with weblink:

leggedRobot.py (Examples/), reevingSystem.py (Examples/), sliderCrank3DwithANCFbeltDrive2.py (Examples/), ANCFcontactCircle.py (Examples/), ANCFcontactCircle2.py (Examples/), ANCFslidingJoint2D.py (Examples/), ANCFtestHalfcircle.py (Examples/), ANCFtests2.py (Examples/), flexibleRotor3Dtest.py (Examples/), rigidBodyIMUtest.py (Examples/), rigidRotor3DbasicBehaviour.py (Examples/), rigidRotor3DFWBW.py (Examples/), ANCFbeltDrive.py (TestModels/), ANCFgeneralContactCircle.py (TestModels/), ANCFBeamTest.py (TestModels/)

The web version may not be complete. For details, consider also the Exudyn PDF documentation : theDoc.pdf