0
RESEARCH PAPERS

Coupler Cognates for the Double Flier Eight-Bar Linkage

[+] Author and Article Information
Gordon R. Pennock

School of Mechanical Engineering,  Purdue University, West Lafayette, IN 47907-2088pennock@ecn.purdue.edu

Nihar N. Raje

School of Mechanical Engineering,  Purdue University, West Lafayette, IN 47907-2088

J. Mech. Des 127(6), 1145-1151 (Feb 14, 2005) (7 pages) doi:10.1115/1.1992508 History: Received October 21, 2004; Revised February 14, 2005

This paper presents a graphical technique to construct the coupler cognate linkages for the double flier eight-bar linkage. The technique is based on the skew pantograph construction which converts the double flier linkage into a second eight-bar linkage by applying the concepts of stretch rotation and kinematic inversion. Since a stretch-rotation operation preserves the angular velocities of corresponding links of the two linkages then the second linkage has the same input-output motion as the original double flier linkage. Another stretch rotation is performed on the intermediate eight-bar linkage and a third eight-bar linkage, which duplicates the motion of the coupler link of the original linkage, is obtained. This graphical approach, to investigating coupler cognates, is believed to be an original contribution to the study of cognate linkages. The technique can be applied in a straightforward manner, requiring few constructions, and offers significant advantages over well-known analytical techniques which use the locus equation. For the double flier eight-bar linkage, the locus equation is of a high degree and the coefficients can only be obtained from a very laborious procedure. This paper shows the existence of two coupler cognates for each of the two floating binary links of the double flier eight-bar linkage that are connected to the ternary link which is pinned to ground.

FIGURES IN THIS ARTICLE
<>
Copyright © 2005 by American Society of Mechanical Engineers
Topics: Linkages , Rotation
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

(a) The skew pantograph. (b) The two dyads forming a skew pantograph.

Grahic Jump Location
Figure 2

The double flier eight-bar linkage and angular notation

Grahic Jump Location
Figure 3

(a) Points U and V fixed in the coupler link 4. (b) Skew pantograph EF′G′BFG and eight-bar linkage 1′−2−3−4−5′−6′−7′−8′. (c) Points G″, O8″, O5″, E″, F″, B″, C″, A″ and O2″.

Grahic Jump Location
Figure 4

The coupler cognate linkage

Grahic Jump Location
Figure 5

The triangles O5EO5′, O5DO5′ and CDC

Grahic Jump Location
Figure 6

(a) Graphical programming of the first set of stretch rotations. (b) Graphical programming of the second set of stretch rotations.

Grahic Jump Location
Figure 7

(a) The coupler curve traced by point U. (b) The coupler curve traced by point U″.

Grahic Jump Location
Figure 8

Coupler curves traced by points U and U″ and points V and V″

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In