Comprehensive Kinematic Analysis of Higher Pairs with Two Degrees of Freedom
Report ID: TR-421-93Author: Joskowicz, Leo / Sacks, Elisha
Date: 1993-04-00
Pages: 18
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Abstract:
We present a comprehensive kinematic analysis program for higher pairs with two degrees of freedom, such as gears, cams, ratchets, and escapements. The program, called HIPAIR, derives the contact constraints and contact transitions of a pair by computing its configuration space. It generates the contact curves of the interacting features, finds their intersection points, and partitions the resulting space. It derives displacement, velocity, and acceleration plots by simulating driving motions in configuration space. HIPAIR handles intermittent, simultaneous, and degenerate contacts between planar and 2.5D parts. This class contains 90\% of 2.5D pairs and 80\% of all higher pairs according to our survey of 2500 mechanisms from an engineering encyclopedia. HIPAIR analyzes pairs of average shape complexity in under five seconds on a workstation. It facilitates the design and analysis of multipart mechanisms that contain higher pairs. It helps designers detect part interference, establish part clearances, identify functional surfaces, and find jamming and lock-up configurations.