This research proposes a method to prefigure responsive models by investigating the form’s spatial movement in the step from one configuration to another. Folded surfaces have been chosen for investigation. Contemporary architecture proposes buildings that are no longer simply juxtaposed volumes marked by light, i.e., surfaces drawn by shadows that change with the position of the Sun throughout the day. Today, buildings interact with the surrounding environment, changing the morphological characteristics of their exteriors in relation to various environmental parameters. Buildings change in relation to external conditions, but they also communicate via the possibilities expressed by a skin that shimmers in relation to the message to externalize. We are faced with responsive forms that the designer should control through design. The design of forms in movement is seen widely in the study of objects called “folded surfaces”. This area addresses the different means of prefigurement offered by the design used to initially investigate the layout, which is drawn according to canonical rules of symmetry, balance, and the ability to tessellate flat space.
The next step is to translate the signs into mountain and valley folds, studying the different spatial conformations assumed by tiles of the folded surface rotating around the pattern lines. Spatial control of the model is ensured by geometrically controlling the basic entities that compose the folded surfaces: the surface/face of the pattern, the zipper lines between the faces, the point/vertex where the zipper lines meet. By applying the basic rules of descriptive geometry, an algorithm that controls the entire form can be constructed. This is the fundamental contribution of nodal programming tools for modelling support. Today almost all design programs include nodal networks, which allow the geometric algorithms used in the research to be specified and some variable dimensions to be extrapolated from the definition. Acting on the variables, it is possible to control the step from the folded surface of one conformation to another. In this way, the “fourth dimension”, the form’s movement, can be anticipated and designed.