constraining an assembly to one motion

[bahorton]

When I rotate the drive shaft gear very slowly, the assembly follows the the correct motion path, (figure 1), however, when I rotate it quickly, the assembly snaps the linkages to an orientation that is not physically possibe, but satisfies the geometrical constraints (figure 2).  I can't use contact solver because I am using the adaptive function for my sub-assembly to avoid having to re-constrain many parts. 

[JDMather]

It is usually better to impart motion with Drive Constraint (or in the Dynamic Simulation environment) than by dragging with mouse.