Symmetric isostatic frameworks with $\ell^1$ or $\ell^\infty$ distance   constraints
  Combinatorial characterisations of minimal rigidity are obtained for symmetric 2-dimensional bar-joint frameworks with either $\ell^1$ or $\ell^\infty$ distance constraints. The characterisations are expressed in terms of symmetric tree packings and the number of edges fixed by the symmetry operations. The proof uses new Henneberg-type inductive construction schemes. 
Derek Kitson and Bernd Schulze
math.CO math.MG