Inflection Circle Based Approach to Synthesis of Approximate Straight Line Mechanisms

Abstract

Extra effort required to create and maintain the sliding pair in mechanisms producing linear motion calls for developing mechanisms without sliders and guide-ways for them. Considerable work has been done in identifying straight line mechanisms, approximate and exact; but the available choices are limited. Very few slider-crank mechanisms can trace an approximate straight line path longer than two times the crank radius. For the planer mechanism In-flection Circle, at every instant; is the locus of points tending to follow a straight line path along the tangent to the inflection circle at that point. For the given crank rocker four bar chain, there has to be a set of points which are common to multiple Inflection circles of the mechanism. These points when converted into coupler points are expected to trace the longest straight line path for the given mechanism. In this exploration, effort has been done to identify and analyze the behavior of such points by tracing the coupler curves in the fixed link frame. To understand the interrelationship among various variables present, the approach of Generated Data Based Modeling has been used. Young areas like ‘Compliant Mechanisms’ are expected to be immediate beneficiaries of these results.