Synthesis and Analysis of a Novel Linkage Mechanism with the Helical Motion of the End-Effector

Abstract

<jats:p>The proposed study is focused on the development of a novel modification of the slider-crank mechanism, the kinematic scheme of which is organized by coupling planar and spatial (screw) kinematic chains. The structure of this mechanism provides the end-effector with a cyclic movement along a helicoidal trajectory, while all other links have planar motions. A kinematic analysis of the synthesized mechanism is discussed in this study. The motion variables of the end-effector at different pitches in the screw joints are determined analytically and numerically. Based on the mechanism’s kinematic scheme, its assembling computer-aided design (CAD) model has been created, in accordance with which a physical prototype has been built. A functional performance of the prototype is studied by comparing the displacements of its end-effector with analogical displacements of the CAD model. The question of the technological application of the developed mechanism for spring winding and various objects’ screwing has been considered in this study.</jats:p>

Improvement on Planar Mechanism Composition Principle

“…According to the concept that freedom is the number of independent motion parameters, so the system whose freedom is zero can´t move. The freedom of the basic linkage group is zero [3]. But the basic linkage group is movable.…”

“…We should judge it according to the definition and the practical examples of the basic linkage group. If the special mechanism using the PPP type basic linkage group can be found, and then the existing characteristics of the PPP type basic linkage group can be proved, and so the errors that exclude the PPP type basic linkage group can be corrected in the university textbooks [3,5].…”