Cross-ratios of quadrilateral linkages

Giorgi Khimshiashvili and Dirk Siersma

Journal of Singularities
volume 13 (2015), 159-168

Received 19 August 2013. Received in revised form 25 November 2014.

DOI: 10.5427/jsing.2015.13h

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We discuss the cross-ratio map of planar quadrilateral linkages, also in the case when one of the links is telescopic. Most of our results are valid for a planar quadrilateral linkage with generic lengths of the sides. In particular, we describe the image of cross-ratio map for quadrilateral linkage and planar robot 3-arm.


quadrilateral linkage, robot 3-arm, moduli space, cross-ratio

Author(s) information:

Giorgi Khimshiashvili Dirk Siersma
Ilia State University Utrecht University
Tbilisi, Georgia The Netherlands