Forces

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Forces

Forces

The commands in the Forces menu and Forces toolbar add, measure, and configure kinetostatic forces.

To calculate the forces that act on Parts, there must be a minimum of one kinematic-chain that is kinematically-defined, which has a minimum of one Part with Mass and/or Inertia* and/or there is a Spring to apply a force.

To calculate the forces correctly, you must make sure the Power flows correctly through the kinematic-chain - see Configure Power Source.


Mass Properties

Parts have three sources of Mass and Inertia*. The sources are:

Profile / Extrusions - see Extrusion > Mass Properties

User Mass Properties - see CAD-Line > Mass Properties tab > User Mass Properties

SolidWorks Mass Properties - see CAD-Line > Mass Properties tab > SOLIDWORKS Mass Properties

We add together the three sources of Mass and Inertia.


* the correct term for Inertia is Mass Moment of Inertia. It has SI units of .

Note:

If a Part has Mass but does not have Inertia (Mass Moment of Inertia), it is a Point-Mass, - mass that is concentrated at a point. In reality, this is not possible (we do not model singularities or Black-Holes!) However, we allow the concept.

In reality, when a Part has Mass it must also have Inertia*. The Inertia* is a summary of how the mass in the Part is distributed around its Center-of-Mass, and where the Center-of-Mass is located in the Part.


MD-Globe-www On-line Tutorial: Tutorial 13: Forces Introduction


 

Force menu

 Forces menu (MD17)

 Forces menu (MD17)


Force toolbar

The Force toolbar is to the right of the graphics-area.

Forces toolbar

Forces toolbar


Buttons to Scale Vectors in the graphics-area.

MD-Feedback-Area-VectorButtons

If, after you display Force Vectors, the arrowheads of the vectors are outside of the graphics-area, you must use the Scale buttons to decrease the length of the Force Vectors and/or Torque Vectors - see Feedback Area > Vector Scaling buttons


tog_minusKinetostatic Forces - Definitions:
tog_minusAcceleration Definitions:

We calculate for you those Forces that result from these Accelerations :