Solving Geometric Constraint Systems: A Case Study in Kinematics

Solving Geometric Constraints records and explains the formal basis for graphical analysis techniques that have been used for decades in engineering disciplines. It describes a novel computer implementation of a 3D graphical analysis method - degrees of freedom analysis - for solving geometric constraint problems of the type encountered in the kinematic analysis of mechanical linkages, providing the best computational bounds yet achieved for this class of problems. The technique allows for the design of algorithms that provide significant speed increases and. will foster the development of interactive software tools for the simulation, optimization, and design of complex mechanical devices as well as provide leverage in other geometric domains.

Kramer formalizes symbolic geometry, including explicit reasoning about degrees of freedom, as an alternative to symbolic algebraic or iterative numerical techniques for solving geometric constraint satisfaction problems. He discusses both the theoretical and practical advantages of degrees of freedom analysis, including a correctness proof of the procedure, and clearly defines its scope. He covers all nondegenerate cases and handles several classes of degeneracy, giving examples that are practical and of representative complexity.

Glenn A. Kramer is Research Scientist at the Schlumberger Laboratory for Computer Science.