COMSOL 6.2 - Spring and Damper

Use the subnode to apply elastic and viscous forces to restrict and control the relative motion on joint. You can also use a dashpot to model various kind of losses in the joint. This node can be added more than once if required, and the effects will then be superimposed. Each joint type has different settings sections.

The subnode can be added to the Prismatic Joint, Hinge Joint, Cylindrical Joint, Screw Joint, Planar Joint, Ball Joint, Slot Joint, and Reduced Slot Joint. The contents of the settings sections will differ between different joint types

	The Theory for Springs and Dampers on Joints section describes the theory for each of the different types of springs and dampers: translational, rotational, inclination angle, and axial rotation.

This section is available for the Prismatic Joint, Cylindrical Joint, Screw Joint, Planar Joint, Slot Joint, and Reduced Slot Joint nodes.

Select a — or .

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For , enter an expression for Fs. The expression can be a function of the spring extension. The built-in variable for the spring extension has the form <physicsName>.<JointTag>.<SpringAndDamperTag>.us (for example, mbd.prj1.sd1.us).

To add a predeformation of the spring, enter u0. To add viscous damping in a dynamic analysis, enter a value or expression for the cu.

For the , enter values or expressions for the es0. Also select the — or . For enter values or expressions for ed0.

This section is available for the Hinge Joint, Cylindrical Joint, Screw Joint, Planar Joint, and Reduced Slot Joint nodes.

Select a — or .

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For , enter an expression for Ms. The expression can be a function of the spring rotation. The built-in variable for the spring rotation has the form <physicsName>.<JointTag>.<SpringAndDamperTag>.ths (for example, mbd.hgj1.sd1.ths).

To add a predeformation of the spring, enter θ0. To add viscous damping in a dynamic analysis, enter a value or expression for the cθ.

This section is available for Ball Joint and Slot Joint nodes.

Select the — , , or . For enter values for eR0.

Select a — or .

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To add a predeformation of the spring, enter θ0. To add viscous damping in a dynamic analysis, enter a value or expression for the cθ.

This section is available for Ball Joint and Slot Joint nodes.

Select a — or .

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To add a predeformation of the spring, enter ψ0. To add viscous damping in a dynamic analysis, enter a value or expression for the cψ.

Physics tab with , , , , , , , or selected in the model tree: