Trajectory singularities of general planar motions
Peter Donelan, Christopher G. Gibson, W. Hawes · Proceedings of the Royal Society of Edinburgh Section A Mathematics · 1999
Local models are given for the singularities that can appear on the trajectories ofgeneral motions of the plane with more than two degrees of freedom. Versal unfoldings of these model singularities give rise to computer-generated pictures describing the family of trajectories arising from small deformations of the tracing point, and determine the local structure of the bifurcation curves.