Sphere Torus Contact - MapleSim Help

Online Help

All Products    Maple    MapleSim


Home : Support : Online Help : MapleSim : MapleSim Component Library : Multibody : Contacts : Forces : componentLibrary/multibody/contacts/forces/SphereTorusContact

Sphere Torus Contact

Sphere-torus contact force model

 

Description

Connections

Parameters

Description

The Sphere Torus Contact model connects Sphere and Torus contact elements.

Activation

Contact forces are generated only when the contacts are enabled.

The active parameter selects how the contacts are enabled. It has the following settings:

Always Active, the default, means the contacts are always enabled.

Boolean Signal means the contacts are enabled when the enable contact boolean input is true.

Start/Stop Time means the contacts are enabled at specified start time, Ton, and disabled at a specified stop time, Toff.

The on/off parameter is used with the Start/Stop Time selection and has the following settings:

Start Time means the contacts are enabled at Ton.

Stop Time means the contacts are disabled at Toff.

Start/Stop Time means the contacts are enabled at Ton and disabled at Toff.

Contact Properties

The use record boolean parameter, if enabled, specifies the name of an external record parameter that defines the parameters of the contact.

The mode parameter selects one of three modes: Linear spring and damper, Linear spring and limited damper, and Hunt and Crossley. The first two use the c and d parameters to set the spring and damping constants. The Hunt and Crossley model uses the parameters cn, dn, n, p, and q. See the Multibody Contact Modes help page for the resulting force equations.

The μ parameter is the coefficient of friction between contacting bodies.

The kμ parameter is a smoothness coefficient for sliding friction, it scales μ by tanhkμvt, where vt is the tangential velocity.

The ε parameter specifies a minimum length used when normalizing vectors.

Connections

Name

Description

Modelica ID

enablecontact

Optional boolean input; enable contact

enable_contact

port1

Connection to spheres

port_1

port2

Connection to tori

port_2

Parameters

Name

Default

Units

Description

Modelica ID

active

Always Active

-

Selects contact activation

active

on/off

Start Time

-

Selects start/stop times

onoff

Ton

0

s

On time

Ton

Toff

0

s

Off time

Toff

use record

false

-

Use contact properties record

useRecord

mode

Linear spring and damper

-

Contact force formulation

mode

c

104

Nm

Spring constant (c>0)

c

d

0

Nsm

Damping constant

d

cn

104

-

Nonlinear spring constant (cn>0)

cn

dn

0

-

Nonlinear damping constant

dn

n

1.5

-

Nonlinear elastic force exponent

n

p

n

-

Nonlinear damping force exponent

p

q

1

-

Nonlinear damping force exponent

q

μ

0

-

Coefficient of friction

mu

kμ

1

-

Smoothness coefficient for sliding friction

kTANH

ε

1.10−6

-

Minimum length of vectors for normalization

eps

contact properties

 

-

Name of contact property record component

conparams

nsphere

1

-

Number of spheres

nSphere

use sphere to sphere contact

false

-

True (checked) means model contacts between the spheres

useSphereSphereContact

ntorus

1

-

Number of tori

nTorus

use torus to torus contact

false

-

True (checked) means model contacts between tori

useTorusTorusContact

ktol

0.001

-

If the length of the projection of the line connecting the center of the sphere to the center of the torus onto the plane of the torus is smaller than small torus radius times Ktol, then concentric contact condition is assumed

Ktol

kconv

1.10−9

-

Error control used in iterative contact point calculations

Kconv

niter

1000

-

Maximum number of iterations

Niter

See Also

Forces

Multibody

Multibody Contacts