Derivation of a standard set of geometric constraints for parametric modeling and data exchange

This paper describes the derivation of a consistent and comprehensive set of geometrical constraints for shape definition in CAD. Such a set is needed to enable compatibility in parametric data exchange and to promote both standard capabilities and predictable solutions from constraint solving software kernels. The paper looks at the mathematical basis for constraints present in the literature and elaborates about all types of constraints that can be described by the same mathematical basis. Exhaustive combinations of distance and angle constraints, on one point or all points of curves and surfaces, as well as transformations and mappings that are required in mechanical design are included in the proposed taxonomy and representation. Consistency is promoted by distinguishing necessary constraint types from redundant constraint types. Comprehensiveness is promoted by including all constraint types from the literature that are within the scope and considering combinatorial variations of them. (C) 2000 Elsevier Science Ltd. All rights reserved.