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$\newcommand{\lyxlock}{}$
Subsubsection 3.11.2.5: Rigid Planar Joint Up Subsection 3.11.2: Rigid Connectors Subsubsection 3.11.2.7: Rigid Spring

#### 3.11.2.6 Rigid Lock Joint

A rigid lock connects rigid bodies and , preventing relative motion between them. It requires the specification of a joint origin and two orthgonal axes and .
In addition to the shared parameters above, it defines the following parameters.
 parameter Description joint_origin The position of the joint. first_axis The first axis. second_axis The second axis.
The tolerance element defines the augmentation tolerance. That is, when the relative change in the constraint forces and moments (the Lagrange multipliers) are less than this value. The gaptol element defines the tolerance for spatial separation of the joint origin on the two bodies (in units of length). The angtol element defines the tolerance for angular separation of the joint axes on the two bodies (in units of radians). Setting any of these three elements to zero disables the enforcement of that tolerance. The force_penalty parameter (with units of force per length) represents the stiffness that prevents the joint origin on the two bodies from separating along the rotation axis. The moment_penalty parameter (with units of moment per radians) represents the torsional stiffness that enforces parallelism of the joint rotation axis on the two bodies. The body_a and body_b elements are the material numbers of the two rigid bodies. The joint_origin element defines the position of the joint (the origin of the basis in world coordinates at the start of the analysis. Note that this point does not have to be inside or on the surface of either of the two bodies. The first_axis element defines the orientation of the axis in world coordinates at the start of the analysis. The second_axis element defines the orientation of the second axis in world coordinates at the start of the analysis.
Example:
<constraint type="rigid lock" name="Joint01">
<tolerance>0</tolerance>
<gaptol>1e-4</gaptol>
<angtol>1e-4</angtol>
<force_penalty>1e0</force_penalty>
<moment_penalty>1e0</moment_penalty>
<auto_penalty>1</auto_penalty>
<body_a>1</body_a>
<body_b>2</body_b>
<joint_origin>0,0,0</joint_origin>
<first_axis>1,0,0</first_axis>
<second_axis>0,1,0</second_axis>
</constraint>

Subsubsection 3.11.2.5: Rigid Planar Joint Up Subsection 3.11.2: Rigid Connectors Subsubsection 3.11.2.7: Rigid Spring