FEM ConstraintRigidBody
FEM ConstraintRigidBody |
Menu location |
---|
Model → Mechanical boundary conditions and loads → Constraint rigid body |
Workbenches |
FEM |
Default shortcut |
None |
Introduced in version |
1.0 |
See also |
FEM Constraint displacement |
Description
Defines the CalculiX's rigid body constraint that constrains the motion of the nodes of a selected face to the motion of a reference node whose location is defined by the user. In practice, this can be used to apply a boundary condition or load that will be propagated to the selected face. Since the reference node has rotational degrees of freedom, it's possible to apply a moment load or a rotational boundary condition to any face this way. The location of the reference node can be selected, if it's offset from a face, a remote load (force acting on a lever) can be applied.
Usage
- There are several ways to invoke the command:
- Press the Constraint rigid body button.
- Select the Model → Mechanical boundary conditions and loads → Constraint rigid body option from the menu.
- In the 3D view select face(s) to which the constraint should be applied.
- Specify the coordinates of the reference node.
- Choose modes for the 3 translational and 3 rotational degrees of freedom (DOFs):
- Free - default, no boundary condition or load on that DOF
- Constraint - displacement/rotation boundary condition with a specified value (0 = fixed by default) - for rotation, one needs to set an axis (X, Y or Z) and specify the Angle
- Load - force/moment load with a specified value
Limitations
- Currently, the moment units can be somewhat confusing. To apply 1 N*m, one needs to set 1 J in the input field (those units are equivalent).
- The feature can be applied only to faces for now, supports for solids (to make whole volumes/parts rigid) should follow in the future.
- The selected face is made rigid. To apply loads in a more flexible way, one would need to use CalculiX's distributing coupling constraints which are currently unsupported.
Notes
- This feature uses the *RIGID BODY card in CalculiX.
FEM
- Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor
- Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)
Constraints
- Electromagnetic: Electrostatic potential, Current density, Magnetization
- Geometrical: Plane rotation, Section print, Transform
- Mechanical: Fixed, Displacement, Contact, Tie, Spring, Force, Pressure, Centrif, Self weight
- Thermal: Initial temperature, Heat flux, Temperature, Body heat source
- Overwrite Constants: Constant vacuum permittivity
- Solve: CalculiX Standard, Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run
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- Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types
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