Sfsf

Model Element

Class Name

Sfsf

Description

Sfsf defines a higher pair constraint. The constraint consists of a surface on one body rolling and sliding on a surface on a second body. The surfaces are required to have a unique contact point.

Attribute Summary

Name	Property	Modifiable by command?
id	Int ()
label	Str ()	✓
isurface	Reference ("Surface")	✓
jsurface	Reference ("Surface")	✓
irm	Reference ("Marker")	✓
jrm	Reference ("Marker")	✓
idisp	Double ([0,0,0], count=3)
jdisp	Double ([0,0,0], count=3)
active	Bool ()	✓

Usage

Sfsf (isurface=objSurface, irm=objMarker, jsurface=objSurface, jrm=objMarker, optional_attributes)

Attribute Description

isurface

Reference to an existing surface

Specifies the surface that is fixed to the first body.

The attribute isurface is mandatory.

irm

Reference to an existing Marker

Specifies a fixed marker that defines the coordinate system in which the ISURFACE points are defined. It also implicitly defines the body on which the surface is "etched". The surface moves with the body.

The attribute irm is mandatory.

jsurface

Reference to an existing surface

Specifies the surface that is fixed to the second body.

The attribute jsurface is mandatory.

jrm

Reference to an existing Marker

The attribute jrm is mandatory.

Integer

Specifies the element identification number. This number must be unique among all the Sfsf objects in the model.

This attribute is optional. MotionSolve will automatically create an ID when one is not specified.

Range of values: id > 0

label

String

Specifies the name of the Sfsf object.

This attribute is optional. When not specified, MotionSolve will create a label for you.

idisp

List of 3 doubles

These three values specify the location of the contact point on isurface at the input configuration as measured in the irm coordinate system.

The three values come as a set. All three must be specified or none may be defined.

This attribute is optional.

jdisp

List of 3 doubles

These three parameters specify the location of the contact point on jsurface at the input configuration as measured in the jrm coordinate system. The three parameters come as a set. All three must be specified or none may be defined.

This attribute is optional.

active

Bool

Select one from True or False.

•	True indicates that the element is active in the model and it affects the behavior of the system

•	False indicates that the element is inactive in the model and it does not affect the behavior of the system. It is almost as if the entity was removed from the model, of course with the exception that can be turned “ON” when desirable.

The attribute active is optional. When not specified, active defaults to True

Comments

1.	See Properties, for an explanation about what properties are, why they are used and how you can extend these.

2.	For a more detailed explanation about SfSf, see the Comments in the XML syntax section.

Example

1.	Create two surfaces and define an Sfsf constraint between them.

# Create the first surface object

surf1 = Surface (function=”user (10)”, routine=Surface1, uclosed=True, vclosed=False,

minpar=[0, -150], maxpar=[2*pi, 150], label=”Surf-1”)

# Create the second surface object

surf2 = Surface (function=”user (10)”, routine= Surface2, uclosed=True, vclosed=False,

minpar=[0, -1], maxpar=[2, 15], label=”Surf-2”)

ic1 = [1.466,5.66,0.1]

ic2 = [-0.522,-0.852,-0.453]

sfsf1 = Sfsf (isurface=surf1, irm=m1, jsurface=surf2, jrm=m2, idisp=ic1, jdisp=ic2)