A method and assembly for processing, viewing and installing command information transmitted via a peripheral device for manipulating 3D modelling image(s). The peripheral device is a gripping element manipulated by a user and has sensors which detect forces and/or displacements on the gripping element and, as a result of detected forces and/or displacements, generate command information, some corresponding to translation or zoom components, and others to rotation components for the movement to be conferred to a spatial representation of the 3D modelling. In a first operating mode a set of command information is processed to modify the displayed image(s) by imparting thereto only movements of rotation in space and in that in a second operating mode a set of command information is processed to modify the displayed image(s) by imparting thereto only movements of translation or a zoom effect. The method is applicable to a surgical theater and/or examination room.