Siemens PLM Software announces the latest release of the D-Cubed 2D Dimensional Constraint Manager (2D DCM), a software component that controls 2D parametric sketches in 2D and 3D design environments. Some of the new features specific to version 59.0 are listed below.
Functional enhancement: New support for conics
Version 59.0 introduces support for conics, representing a major addition to the geometry types that can be constrained with the 2D DCM. Conics are commonly used in CAD systems to model edges with varying curvature that are aesthetically pleasing and are often used to represent a blend between two edges. A conic section is a 2D curve that results from the intersection of a plane and a cone. There are three different types, which can be classified according to how the plane intersects the cone.
The 2D DCM operates on bounded regions of conics. A conic curve is defined in the 2D DCM using three control points and a parameter value, rho (“ρ”). Two of the control points specify the end points of the bounded conic curve. The relative position of the third point influences the tangent direction of the curve at the end points. The parameter value determines the type of conic curve, as shown in the examples below.
D-Cubed 2D DCM
The 2D DCM supports a wide range of dimensions and constraints on conics, such as distance, tangency, pattern and symmetry.
While it was previously possible to model specific conic types using parametric geometry, the introduction of dedicated support for conics enables applications to implement these curves more efficiently using a simple and intuitive definition. Much more flexible dimensioning schemes are also possible using conics. For example, applications can choose to fix the conic type (by constraining the parameter value to the relevant range), or make this a degree of freedom, enabling the 2D DCM to switch between types to satisfy the dimensions and constraints.
With the addition of conic sections, version 59.0 offers software developers an even wider range of curve types that can be controlled with an extensive variety of geometric constraints to create the world’s best design and styling applications.
Performance enhancement: Partition-specific solving
Performance optimization projects feature in most 2D DCM development cycles and version 59.0 is no exception. Partition-specific solving has been introduced to significantly improve the speed at which applications solve large models where changes have been made which affect a limited region of the dimensioning scheme. A good example drawn from Architecture, Engineering and Construction (AEC) applications might be the modification to a distance between windows in the floor plan of a single room, which is part of a much larger building.
The 2D DCM splits the model into partitions (regions where any changes in the dimensioning scheme will not affect geometry in other regions), for example, creating a partition for each room in a building. While earlier versions of the 2D DCM used partitioning to improve performance by reducing the time taken to solve redundant regions, the 2D DCM still analysed all of the geometry and constraints in a model. New algorithms in version 59 have made this requirement an option, so applications can now specify that only the partition in which changes to the dimensioning scheme are being made will be subject to the solution process.
About the D-Cubed 2D DCM
First released in 1990, the 2D DCM is used in most major CAD applications and is widely acknowledged as the leading 2D geometric constraint solving technology. It provides a variational (non-sequential) approach to solving a broad range of dimension and constraint schemes optimised for use in 2D environments. In addition to driving the sketcher in most mechanical CAD products, it is used in the integral design environments of many other applications, such as CAM and CAE systems.
