It is not necessary to connect wires to the input or output-connectors of the Spring FB. The input and output-connectors provide extra functionality - see here
The Spring dialog is now open.
Spring dialog
Spring FB dialog
Spring Parameters
☑ Select the check-box to enable the Spring FB.
Spring-Rate [N/mm] :
Force Contribution:
= Spring-Rate × |Spring-Length – Free-Length |
Spring-Length is the distance between the two anchor-points.
The Force always acts on the anchor-points to return the Spring to its Free-Length (which, in a kinetostatic force analysis, it cannot).
Note:
Do not enter a negative Spring-Rate (In a new release, we will make sure you cannot enter a negative number).
Free-Length [mm] :
The natural length of the Spring when it is not joined to the Anchor-Points.
Constant-Force [N]
A positive Constant-ForcePULLS the Anchor-Points together (o>>> + <<<o)
A negative Constant-ForcePUSHES theAnchor-Points apart (o<<< — >>>o)
Velocity Parameters
Coulomb (Constant) Friction Force
A constant force that is opposite to the direction of the motion.
In a kinetostatic force analysis, you can use it to approximate a Friction-Force.
Note:
The Friction-Force between two bodies in contact at a joint is proportional (approximately) to the force that acts on the bodies at the joint.
However, because the force acting between the two bodies is usually not constant, the Friction Force is also NOT constant.
Viscous Coefficient ( )
A Force that is proportional to the velocity between the Anchor-Points.
The direction of the force is opposite to the velocity between the Anchor-Points.
For example, if theDamping Coefficient = 4 and the Velocity is +100mm/s, (anchor points moving away from each other), the force pulling the points together is a force of 400N.
Drag Factor ( )
A Force that is proportional to square of the velocity between the Anchor-Points. For example, air resistance.
The direction of the force is opposite to the velocity between the Anchor-Points.
For example, if theDrag Factor = 4, and the Velocity = +100mm/s (anchor-points are moving apart), then the force pulling the anchor-points together is a force of 40000N.
Input and output-Connectors
Output-Connectors
The Spring-FB has two output-connectors.
Top :
Distance, Velocity, Acceleration of the dimension between the anchor-points.
Bottom :
Total Force,
Force-X (force parallel with the X-axis of the Mechanism-Editor), and
Force-Y (force parallel with the Y-axis of the Mechanism-Editor) acting on anchor-points.
or
Driving-Force = Linear Motive Force, if you configure the Spring FB as a Linear Motor - see Configure Power Source
Input-Connector
The Spring-FB has one input-connector.
Connect a wire to the input-connector of a Spring FB to add a Force-Function to the Total-Force that is exerted by the Spring-FB.
The units of the data at the input-connector must be units of Force, for example, Newtons.
If necessary, use a Math FB to convert data and its units to Force units.
For example: To convert 100mm to 100N, you must:
1.Add a Math FB to the graphics-area
2.Connect a wire to the input-connector of the Math FB from a Function-Block that measures a distance - constant or variable.
