Form finding of light structures with non linear constraints

In the form finding process the final configuration and the initial configuration are not known, only the parametric domain is fixed, and some topological constraints. In the standard form finding process the current, final, configuration is sought, and the initial is then obtained removing the elastic deformation. In doing this, a non compatible form is in general found. However there are cases for which is important to obtain an initial configuration that complies with specific requirements, like in the case of the patterning of the membranes, or when the membrane is used as formwork of concrete shells etc. In this case a non linear process is needed in order to enforce the constraints on the strain state. The work aims to present a general framework of form finding based on the concepts of configurational mechanics that can be used for solving some of the problems indicated above. A numerical approximation of the geonmetry based on B-spline interpolation, which guarantees high continuity degree, is us.