Loads
2D/3D

• Loads[bnum] returns the total external load applied to body bnum.
• Loads[{bnum1, bnum2, ... }] returns the subset of the applied load vector associated with the bnumi.
• Loads[All] returns the entire applied load vector.
• Loads[Rest] returns the subset of the applied load vector that is associated with derivatives of generalized coordinates, such as the extra variables introduced by cam constraints.
• Loads[sym] returns the element of the load vector associated with coordinate sym.
• Loads[{sym1, ... , symn}] returns the subset of the applied load vector associated with several coordinate symbols.

• The symi must be location coordinates as returned by Location[bnum] or, if the current Modeler3D solution method is Angular, angular velocity coordinates as returned by Omega[bnum].
• The following options can be givens:

• The default setting Coordinates->Automatic returns the loads in the current default coordinate system.
• If Coordinates->Automatic is given and the current coordinate system is Euler, a list of seven loads is returned in Euler coordinates.
• If either the Global or Local setting is given for Coordinates, the argument must be a single body number bnum. In this case Loads returns a two-element list of the form {force, moment}.
• Type->Reaction may be given to return the total reaction force applied by all constraints to the body.
• Type->Dynamic may be given to return the total inertial load on the body.
• For example: Loads[n, Type->Applied] + Loads[n, Type->Dynamic] + Loads[n, Type->Reaction] /. SolveMech[ ... , Solution->Dynamic] should always return a zero vector.
• See also: Constraints.

Further Examples

Load the Modeler2D package and define a simple model.

In[1]:=

Here are the loads applied to the x, y, and coordinates of the link body.

In[2]:=

Out[2]=

Here is the reaction force applied by the constraints to the X3 coordinate (which is the x coordinate of the link body).

In[3]:=

Out[3]=

Here are the dynamic force and moment acting on the link body, with the force given in the local coordinate system of the link body.

In[4]:=

Out[4]=

See HelpModel2D.