Spring FB

Use a Spring FB to impose a force to act between two Points that are in two different Parts. The two Points are the Spring's 'Anchor-Points'.

Use the Spring FB dialog-box to edit the force parameters.


Forces toolbar > Add Spring FB


Add menu > Forces sub-menu > Add Spring FB


Spring FB dialog-box.

How to add:

1.Click Forces toolbar > Add Spring FB
2.Click two different Points in the graphic-area - one Point in two different Parts.

The Spring FB and the symbol of the Spring is now in the graphic-area.

The Points you select for the spring are termed the its Anchor Points.


Spring FB : symbols in graphic-area.

The Spring FB element has three symbols in the graphic-area:

Symbol 11s-red: FB - see below Spring FB connectors

Symbol 22s: Spring is between the anchor-points

Symbol 33s: Dimension between the anchor-points.

Spring FB1s


Top: Distance, Velocity, Acceleration of the dimension between the anchor-points.
Bottom: Total Force, Force-X, Force-Y between the anchor-points.


If you want the output from the Force FB to be a function that you cannot define with parameters in the Spring FB dialog-box, you must apply a Force 'function' at the input-connector.
The data-values at the input-connector to the Spring must be Force units, [SI Newtons]. Specify units of a wire [the data-type] with a Maths FB, and make the Output Data Type as Force [N].
The variation of the Force data-values can be any function.

For example, the output from a Motion FB, and via a Maths FB, can define the Force 'function' between the Anchor-Points.


Spring FB in the graphic-area.

The Spring FB can be in three different states:

State 1: Active Spring FB

This is the 'default' setting.


State 2: Disabled Spring FB

Use the Spring FB dialog-box to deselect the Enable Check-box.



State 3: Linear Motor

Use the Configure Power Source dialog-box to select the Spring as the 'Power Source', and it becomes a Linear Motor.

tog_minus        How to Open the Spring FB dialog-box


To open the Spring FB dialog-box:

1.Double-click the Spring FB in the graphic-area1s-red

- or -

1.Double-click the Symbol of the Spring2s in the graphic-area - see image

- or -

see 'How to open a Dialog-Box'

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd