a small project (modified)

In the first draft of this post, from July 5, I suggested a project to study configurations in space of a ring made of four sticks of known lengths.  But in  talking with McSteve we realized that the project was really best thought of in terms tetrahedra, so I am...

Some starting projects (June 13)

Project 1: The tetrahelix turns out to be a sequence of points H(n)= (r cos(theta n),r sin(theta n), m n) on a helix, where the constants r, theta, m should be determined by the requirement that each edge of the tetrahedron H(n) H(n+1) H(n+2) H(n+3) has length 1.  ...

Terry notes June 8

K. Walker, Configuration spaces of linkages, undergrad.thesis, princeton 1965 http://canyon23.net/math/ Kevin Walker’s post of thesis says error in proof of 3.3, see Hausmann, sur la topologie des bras articules ’89 (I have a photocopy) +++...