Joint II
Two rigid shell elements are joined together using a revolute joint. A stop angle is defined so that the rotating plate can only rotate 30 degrees relative to the other plate.
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Joint II
Two rigid shell elements are joined together using a revolute joint. A stop angle is defined so that the rotating plate can only rotate 30 degrees relative to the other plate.
*CONSTRAINED_JOINT_REVOLUTE Hinged Shell with Stop Angle (Revolute Joint) LS-DYNA Manual Section: *CONSTRAINED_JOINT_REVOLUTE Additional Sections: *CONSTRAINED_JOINT_STIFFNESS *CONTROL_TIMESTEP Example: Hinged Shell with Stop Angle (Revolute Joint) Filename: constrained.joint_revolute.k Description: Two rigid shell elements are joined together using a revolute joint. A stop angle is defined so that the rotating plate can only rotate 30 degrees relative to the other plate. Model: A pair of concentrated loads are applied to the end nodes of a hinge-jointed shell system using * LOAD_NODE_POINT. One of the rigid plates is fixed by using the capability within the *MAT_R IGID keyword. The rotating plate has a stop angle of 30 degrees relative to the fixed plate defined using the *CONSTRAINED_JOINT_STIFFNESS_GENERALIZED keyword. Because all components in the model are rigid, the time step needs to be controlled by limiting the maximum time step to 4.15E-06 s.(In deformable structures, the minimum time step is usually the one of concern.) Results: The rotating plate at several states are shown imposed on each other. The maximum rotated angle is closer to 38 degrees rather than the specified 30 degrees. This is because the joint stiffness actual defines the angle at which the resistance force is to begin. The forces associated with stopping the rotating plate can be determined by examining the jntforc ascii file.
*CONSTRAINED_JOINT_REVOLUTE *CONSTRAINED_JOINT_STIFFNESS_GENERALIZED *CONTROL_TERMINATION *CONTROL_TIMESTEP *DATABASE_BINARY_D3PLOT *DATABASE_GLSTAT *DATABASE_HISTORY_NODE *DATABASE_JNTFORC *DATABASE_NODOUT *DATABASE_RBDOUT *DEFINE_COORDINATE_NODES *DEFINE_CURVE *ELEMENT_SHELL *END *KEYWORD *LOAD_NODE_POINT *MAT_RIGID *NODE *PART *SECTION_SHELL *TITLE
*KEYWORD
*TITLE
hinged shell w/ stop angle
$
$ LSTC Example
$
$ Last Modified: October 16, 1997
$
$ - This problem has a pair of concentrated loads applied to
$ the end nodes of a hinge-jointed shell system.
$
$ - 30 degree stop angle (must add joint stiffness, local coord system)
$
$ - control timestep with maximum 4.15E-06
$
$ Units: lbf-s2/in, in, s, lbf, psi, lbf-in
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Control Ouput
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*CONTROL_TERMINATION
$ endtim endcyc dtmin endeng endmas
2.000E-02
$
*CONTROL_TIMESTEP
$ dtinit scft isdo tslimt dtms lctm erode ms1st
5
$
*DEFINE_CURVE
$ lcid sidr scla sclo offa offo
5
$ abscissa ordinate
0.0 4.15E-06
1.0 4.15E-06
$
$
*DATABASE_BINARY_D3PLOT
$ dt lcdt
5.000E-04
$
*DATABASE_GLSTAT
$ dt
0.0001
$
*DATABASE_JNTFORC
$ dt
1.000E-04
$
*DATABASE_NODOUT
$ dt
0.0001
$
*DATABASE_HISTORY_NODE
$ nid1 nid2
3 4
$
*DATABASE_RBDOUT
$ dt
0.0001
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Revolute Joint
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*CONSTRAINED_JOINT_REVOLUTE
$
$ Create a revolute joint between two rigid bodies. The rigid bodies must
$ share a common edge to define the joint along. This edge, however, must
$ not have the nodes merged together. Rigid bodies A and B will rotate
$ relative to each other along the axis defined by the common edge.
$
$ Nodes 1 and 2 are on rigid body A and coincide with nodes 9 and 10
$ on rigid body B, respectively. (This defines the axis of rotation.)
$
$ The relative penalty stiffness on the revolute joint is to be 1.0,
$ the joint is well lubricated, thus no damping at the joint is supplied.
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$ n1 n2 n3 n4 n5 n6 rps damp
1 9 2 10 1.0
$
$
$
$$$$$$$$$$$$ Define a joint stiffness for the revolute joint described above.
$
$ Attributes of the joint stiffness:
$ - Used for defining a stop angle of 30 degrees rotation
$ (i.e., the joint allows a positive rotation of 30 degrees and
$ then imparts an elastic stiffness to prevent futher rotation)
$ - Define between rigid body A (part 1) and rigid body B (part 2)
$ - Define a local coordinate system along the revolute axis
$ on rigid body A - nodes 1, 2 and 3 (cid = 5). This is used to
$ define the revolute angles phi (PH), theta (T), and psi (PS).
$ - The elastic stiffness per unit radian for the stop angles
$ are 100, 10, 10 for PH, T, and PS, respectively.
$ - Values not specified are not used during the simulation.
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*CONSTRAINED_JOINT_STIFFNESS_GENERALIZED
$ jsid pidA pidB cidA cidB
1 1 2 5 5
$
$ lcidPH lcidT lcidPS dlcidPH dlcidT dlcidPS
$
$ esPH fmPS esT fmT esPS fmPS
100.0 10.0 10.0
$
$ nsaPH psaPH nsaT psaT nsaPS psaPS
30.0
$
$
*DEFINE_COORDINATE_NODES
$ cid n1 n2 n3
5 1 2 3
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Loading
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*LOAD_NODE_POINT
$ nid dof lcid sf cid m1 m2 m3
3 3 1-1.000E+00
4 3 1-1.000E+00
$
*DEFINE_CURVE
$ lcid sidr scla sclo offa offo
1
$ abscissa ordinate
0.00000000E+00 1.00000000E+00
1.00000000E+00 1.00000000E+00
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Parts and Materials
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
$
*PART
$ pid sid mid eosid hgid grav adpopt
rotating
1 1 1 0
fixed
2 1 2 0
$
$
$$$$ Materials
$
*MAT_RIGID
$
$ mid ro e pr n couple m alias
1 7.000E-04 3.000E+07 3.000E-01
$
$ cmo con1 con2
$
$ lco/a1 a2 a3 v1 v2 v3
$
$
*MAT_RIGID
$
$ mid ro e pr n couple m alias
2 7.000E-04 3.000E+07 3.000E-01
$
$ cmo con1 con2
1.0 7 7
$
$ lco/a1 a2 a3 v1 v2 v3
$
$
$$$$ Sections
$
*SECTION_SHELL
$ sid elform shrf nip propt qr/irid icomp
1 2 3.0
$ t1 t2 t3 t4 nloc
0.1 0.1 0.1 0.1
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$$$$ Define Nodes and Elements
$
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
$
$...>....1....>....2....>....3....>....4....>....5....>....6....>....7....>....8
*END