10.4.2 Planar Example Mechanism

The following example uses the pendulum-on-a-rope model that was developed in Section 10.1. The pendulum is released from a constrained zero velocity position, that is not in static equilibrium, and the free response is found.
The spring force that was used to pull the pendulum off to one side is removed from the model, but gravity is retained. Also, nonzero moments of inertia are defined for each body, since the moments of inertia are relevant to the dynamics of the system, while they were not relevant to the equilibrium analysis.

This loads the Modeler2D package.

In[1]:=

Here are the three body objects, including the new inertia properties.

In[2]:=

The pendulum-on-a-rope model uses seven constraint objects. The constraints that fix the initial position of the model have been altered so that the pendulum may be released from an offset position.

Here are the constraints.

In[3]:=

Here is the gravitational load applied to the pendulum and slider.

In[4]:=

Now the model is run with SolveMech.

In[5]:=

Out[5]=

Here is the pendulum-on-a-rope model in its initial configuration.