you can easily position your rigid 3D parts with respect to each other.
With Driving Dimensions 0.1 for Rhinoceros you can easily position your rigid 3D parts with respect to each other by specifying Assembly constraints (fixation, concentricity, coincidence, parallelism, perpendicularity, or tangency) and driving dimensions (distance and angle) Between their faces and edges. Driving Dimensions plugin automatically satisfies all constraints and dimensions making a consistent assembly from existing parts. An assembled mechanism can then be animated by varying a parameter of one of its driving dimensions. A constraint manager tool allows easy navigation over all assembly constraints and driving dimensions imposed on Geometric elements of a designed model. you can free download Driving Dimensions for Rhinoceros 0.1 now.