On the motion of compliantly-connected rigid bodies in contact. II. A system for analyzing designs for assembly

For pt.I see Cornell Computer Science Tech. Report (1989). A fully algorithmic, combinatorially precise approach to designing devices so that they are easy to assemble and (optional) hard to disassemble is presented. The analysis can be used to validate good designs and can be iterated to generate improved designs. The approach is based on an algorithm for predicting the motion of flexible objects in contact. Such objects are intended to model snap-fastener-type devices, which are very useful in assembly design. The authors describe the algorithm, its implementation in a system for predicting and analyzing the motion of snap-fastener-type devices, and experiments run using the system to analyze and design particular devices. The issues discussed include: the relevance of the approach to engineering, the computational methods employed, the algebraic techniques for predicting motions in contact with rotational compliance, and issues of robustness and stability of the geometric and algebraic algorithms. Subtle mechanical difficulties arise in predicting motions under rotational compliance. The authors discuss these problems and their solutions