*BallJointPair()

Creates a ball joint pair.

Syntax

*BallJointPair(joint_name,"joint_label",body_1, body_2, origin, [ALLOW_COMPLIANCE])

Arguments

joint_name: The variable name of the ball joint pair.; Data type: varname
joint_label: The descriptive label of the ball joint pair.; Data type: label
body_1: The first body or body pair constrained by the ball joint pair.; Data type: Body or BodyPair
body_2: The second body or body pair constrained by the ball joint pair.; Data type: Body or BodyPair
origin: The location(s) of the ball joint pair.; Data type: Point or PointPair
ALLOW_COMPLIANCE: An optional argument that indicates the joint pair can be made compliant.

Example

*BodyPair(b_kn, "Knuckle", p_kn_cm)
*BodyPair(b_lca, "LCA", p_lca_cm)
*PointPair(p_lbj, "Lower Ball Joint")
*BallJointPair(lbj, "Lower Ball", b_kn, 
 b_lca, 
 p_lbj, 
 ALLOW_COMPLIANCE)

Context

*BeginMdl()

*DefineAnalysis()

*DefineSystem()

Properties

Property	Returns Data Type	Description
b1	BodyPair	The first body pair constrained by the ball joint pair.
b2	BodyPair	The second body pair constrained by the ball joint pair.
i	MarkerPair	The marker pair on b1.
isbush	boolean	See ^Comments^.
j	MarkerPair	The marker pair on b2.
l	BallJoint	The left ball joint.
label	string	The descriptive label of the ball joint pair.
r	BallJoint	The right ball joint.
state	boolean	Control state (TRUE or FALSE).
varname	string	The variable name of the ball joint pair.

Comments

The individual joints of a *BallJointPair() can be referred to as joint_name.l (left ball joint) and joint_name.r (right ball joint).The ALLOW_COMPLIANCE argument is optional. When it is included, it indicates that the joint pair can be made compliant. In compliant mode, such joint pairs act as bushing pairs.

The isbush property is valid only for joint pairs that can be made compliant. When isbush is set to FALSE, the joint pair acts like a kinematic joint (in a noncompliant mode). When isbush is set to TRUE, the joint pair acts like a bushing pair (in a compliant mode).

When the compliant option in a system is switched to "non-compliant", all the joint pairs in the system act as kinematic joints. However, when the system option is switched to "compliant", only the joint pairs that are created with an ALLOW_COMPLIANCE flag act as bushing pairs. The rest of the joint pairs continue to behave as kinematic joints.