*CONSTRAINED_JOINT_STIFFNESS

LS-DYNA Input Interface KeywordDefine a stiffness, stop angles and friction for rotational DOFs of a joint between two rigid bodies.

Format

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*CONSTRAINED_JOINT_STIFFNESS_{OPTION}

If OPTION = ID, insert the following line.

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`Title`

If OPTION = GENERALIZED, insert the following line.

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`JSID`	`PIDA`	`PIDB`	`CIDA`	`CIDB`
`LCIDPH`	`LCIDTH`	`LCIDPS`	`LCIDDPH`	`LCIDDTH`	`LCIDDPS`
`ESPH`	`FMPH`	`ESTH`	`FMTH`	`ESPS`	`FMPS`
`NSAPH`	`PSAPH`	`NSATH`	`PSATH`	`NSAPS`	`PSAPS`

Definition

Field	Contents	SI Unit Example
`JSID`	Joint ID. (Integer)
`Title`	Joint title. (Character, maximum 70 characters)
`PIDA`	Part ID for first rigid component. (Integer)
`PIDB`	Part ID for second rigid component. (Integer)
`CIDA`	Coordinate system for the first rigid component. (Integer)
`CIDB`	Coordinate system for the second rigid component. (Integer)
`LCIDPH`	Curve ID for moment versus angle in radians around PHI axis. (Integer)
`LCIDTH`	Curve ID for moment versus angle in radians around THETA axis. (Integer)
`LCIDPS`	Curve ID for moment versus angle in radians around PSI axis. (Integer)
`LCIDDPH`	Curve ID for damping moment versus rotational velocity around PHI axis. (Integer)
`LCIDDTH`	Curve ID for damping moment versus rotational velocity around THETA axis. (Integer)
`LCIDDPS`	Curve ID for damping moment versus rotational velocity around PSI axis. (Integer)
`ESPH`	Elastic stiffness for friction and stop angle around PHI axis. (Integer)	$[\frac{N}{m}]$
`FMPH`	> 0 Friction force for PHI axis. < 0 Curve ID for friction force versus angle for PHI axis. (Integer)	$[N]$ or None
`ESTH`	Elastic stiffness for friction and stop angle around THETA axis. (Integer)	$[\frac{N}{m}]$
`FMTH`	> 0 Friction force for THETA axis. < 0 Curve ID for friction force versus angle for THETA axis. (Integer)	$[N]$ or None
`ESPS`	Elastic stiffness for friction and stop angle around PSI axis. (Integer)	$[\frac{N}{m}]$
`FMPS`	> 0 Friction force for THETA axis. < 0 Curve ID for friction force versus angle for PSI axis. (Integer)	$[N]$ or None
`NSAPH`	Stop angle in negative PHI direction. (Real, positive)	$[\deg]$
`PSAPH`	Stop angle in positive PHI direction. (Real, positive)	$[\deg]$
`NSATH`	Stop angle in negative THETA direction. (Real, positive)	$[\deg]$
`PSATH`	Stop angle in positive THETA direction. (Real, positive)	$[\deg]$
`NSAPS`	Stop angle in negative PSI direction. (Real, positive)	$[\deg]$
`PSAPS`	Stop angle in positive PSI direction. (Real, positive)	$[\deg]$

Comments

This keyword maps to /SPRING, /PROP/TYPE45 (KJOINT2) and /PART.
It works in combination with kinematic joint and determines stiffness, friction, and stop angles for rotational degrees of freedom for joints interconnecting rigid components, PIDA and PIDB.