Degrees of Freedom are key in a Dynamic simulation

Every time I use the Dynamic Simulation environment in Autodesk Inventor Simulation, it seems like I have to alter my assembly constraints to get the results I want. This is usually because of redundant assembly constraints. As an example, lets consider a basic four bar linkage. If you constrain the members with all "insert" type assembly constraints, it may act like you want in the normal Inventor environment, but there is actually a redundant planer constraint in this case. Instead, one of the "insert" constraints should be changed to a "axis/axis" mate constraint.

Shown above is another potentially more troublesome pitfall. This occurs when trying to solve simulations where linkage components serve the same purpose and share loads equally. An example of this could be trying to solve both sides of a scissor lift simultaneously. A better approach would be to only use one half of the model in the simulation and simple divide the input loads in half as well. This allows proper calculation by the simulation tool and allows output of the reaction loads desired.

Contributed by Ben of the Tata Technologies CAD Geeks