# Physics Fun with Jamie: SOLIDWORKS FEA Simulation Fixtures

Article by Jamie Hill, CSWE updated December 27, 2022

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In this blog article we will cover the different fixture types available in SOLIDWORKS FEA Simulation.

### Fixed Geometry Fixture

The Fixed Geometry Fixture in SOLIDWORKS FEA Simulation locks down all degrees of freedom. You can apply this fixture to faces, edges, vertices for solids and shell elements, and beam joints for beam elements. For solid elements this locks the three translational degrees of freedom (because rotation does not exist). For shell and beam elements this locks down all six degrees of freedom (three translational and three rotational). When using this fixture type, no additional reference geometry is needed.

One of the easiest visual cues you can use to tell what a fixture is constraining is to look at the animated image under ‘example’ at the top of the Property Manager window while in the fixture command.

### Immovable Fixture

The Immovable Fixture in SOLIDWORKS FEA Simulation locks down all translational degrees of freedom (X,Y,Z). You can apply this fixture to planes, faces, edges, vertices for shell elements, and beam joints for beam elements. When using this fixture type, no additional reference geometry is needed. You are not able to apply this fixture directly to solid elements as it would be identical to the Fixed Geometry fixture since solid elements do not have rotational degrees of freedom. For shell and beam elements this locks down the three translational degrees of freedom.

One of the easiest visual cues you can use to tell what a fixture is constraining is to look at the animated image under ‘example’ at the top of the Property Manager window while in the fixture command.

### Roller/Slider Fixture

The Roller/Slider Fixture in SOLIDWORKS FEA Simulation locks down one translational degree of freedom (along the in-plane normal direction). You can apply this fixture to planar faces only. When using this fixture type, no additional reference geometry is needed. The roller/slider fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems.

One of the easiest visual cues you can use to tell what a fixture is constraining is to look at the animated image under ‘example’ at the top of the Property Manager window while in the fixture command.

### Fixed Hinge Fixture

The Fixed Hinge Fixture in SOLIDWORKS FEA Simulation locks down two translational degrees of freedom (radial and axial). You can apply this fixture to circular faces and circular edges only. When using this fixture type, no additional reference geometry is needed. This fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems.

### The Symmetry Fixture

The Symmetry Fixture in SOLIDWORKS FEA Simulation locks down one translational degree of freedom (across the lines of symmetry). You can apply this fixture to Planar faces only, but keep in mind all faces along the line of symmetry must be selected (not just one). You can use one Symmetry Fixture for all components across all lines of symmetry. This fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems. When using this fixture type, no additional reference geometry is needed. This fixture is equivalent to a Mirror pattern operation in CAD modeling. Keep in mind everything is mirrored including loads and fixtures, so make sure to adjust your loading accordingly.

### Cyclic Symmetry Fixture

The Cyclic Symmetry Fixture in SOLIDWORKS FEA Simulation locks down four degrees of freedom (two translational degree of freedom across the lines of symmetry with their respective rotational components). You can apply this fixture to faces only. You’ll have to apply one Cyclic Symmetry Fixture per component to get the appropriate constraints across all lines of symmetry. This fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems. When using this fixture type, you will have to provide an axis for the axis of rotation as additional reference geometry. This fixture is equivalent to a Circular pattern operation in CAD modeling. Keep in mind everything is circular patterned including loads and fixtures, so make sure to adjust your loading accordingly.

### Use Reference Geometry Fixture

The Use Reference Geometry Fixture in SOLIDWORKS FEA Simulation locks down one to six degrees of freedom. You can apply this fixture to faces, edges, vertices, and beam joints. When using this fixture type you can select planes, faces, edges, and axes as a geometry reference. If an axis is selected it will convert the default cartesian coordinate system into a cylindrical coordinate system. After selecting where the fixture is being applied and your reference geometry, toggle on one or more of the directions that you want to constrain. For a cartesian based coordinate system reference you have; along plane direction one, along plane direction two, and normal to plane for the translational and rotational components. If an axis is provided as reference geometry a cylindrical coordinate system is used and directions change to; radial, circumferential, and axial for translational and rotational components.

### On Flat Faces Fixture

The On Flat Faces Fixture in SOLIDWORKS FEA Simulation locks down one to six degrees of freedom. You can apply this fixture to planar faces only. After selecting where the fixture is being applied, toggle on one or more of the directions that you want to constrain. You have; along plane direction one, along plane direction two, and normal to plane for the translational and rotational components. When using this fixture type, no additional reference geometry is needed. This fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems.

### On Cylindrical Faces Fixture

The On Cylindrical Faces Fixture in SOLIDWORKS FEA Simulation locks down one to six degrees of freedom. You can apply this fixture to cylindrical faces only. After selecting where the fixture is being applied, toggle on one or more of the directions that you want to constrain. You have; radial, circumferential, and axial for the translational and rotational components. When using this fixture type, no additional reference geometry is needed. This fixture works the same for solid, shell, and beam elements but can not be applied directly to beam geometry or used in pure beam problems.

Another great way to help understand what a fixture is constraining is to look at the fixture symbols in the graphics area, after selecting something while in the fixture command. A green arrow indicates it’s locking down a translational degree of freedom in the direction of the arrow. If you see a disk at the back of the arrow, it indicates it is locking down the rotational component about that direction. For example, in the following image the fixture symbol has three arrows that have three disks which would indicate it is locking down all six degrees of freedom.