An assembly for preforming a reinforced fabric sheet, said reinforced fabric sheet being intended to receive at least one deforming action for making a preformed shell, comprising: - at least one frame; - a plurality of gripping devices suitable for gripping the reinforced fabric sheet, said plurality of gripping devices being directly or indirectly associated with said at least one frame; wherein: - each gripping device of said plurality of gripping devices being suitable for gripping an edge portion of the reinforced fabric sheet; - said assembly further comprises a moving system comprising a plurality of first moving devices; wherein - the movement of each first moving device is independent of the other first moving devices; - each gripping device of said plurality of gripping devices being associated with a first moving device; - said first moving device being suitable for moving each gripping device of said plurality of gripping devices independently of the others so that when said reinforced fabric sheet is gripped by said plurality of gripping devices, each gripping device may move to guide localized deformations of the reinforced fabric sheet which arise during the deforming action of the reinforced fabric sheet; characterized in that - said assembly comprises a plurality of supports, associated either directly or indirectly with said frame, each support of said plurality of supports being also associated either directly or indirectly with at least one gripping device so as to support at least one gripping device; and wherein - each support is associated with a respective gripping device and with a respective first moving device; and wherein - said first moving device is fixed to said support and each gripping device further comprises a carriage associated with said support and adapted to translate with respect to said support when moved by said first moving device; and wherein - at least one support comprises at least one support joint; and wherein - said support is associated with said frame by means of said support joint which guides the rotation of the support with respect to the frame; and wherein said assembly comprises a manipulator robot or device, and wherein said robot is connected to said frame to manipulate said frame in a controlled manner. - at least one frame; - a plurality of gripping devices suitable for gripping the reinforced fabric sheet, said plurality of gripping devices being directly or indirectly associated with said at least one frame; - each gripping device of said plurality of gripping devices being suitable for gripping an edge portion of the reinforced fabric sheet; - said assembly further comprises a moving system comprising a plurality of first moving devices; - the movement of each first moving device is independent of the other first moving devices; - each gripping device of said plurality of gripping devices being associated with a first moving device; - said first moving device being suitable for moving each gripping device of said plurality of gripping devices independently of the others so that when said reinforced fabric sheet is gripped by said plurality of gripping devices, each gripping device may move to guide localized deformations of the reinforced fabric sheet which arise during the deforming action of the reinforced fabric sheet; - said assembly comprises a plurality of supports, associated either directly or indirectly with said frame, each support of said plurality of supports being also associated either directly or indirectly with at least one gripping device so as to support at least one gripping device; and wherein - each support is associated with a respective gripping device and with a respective first moving device; and wherein - said first moving device is fixed to said support and each gripping device further comprises a carriage associated with said support and adapted to translate with respect to said support when moved by said first moving device; and wherein - at least one support comprises at least one support joint; and wherein - said support is associated with said frame by means of said support joint which guides the rotation of the support with respect to the frame; said assembly comprises a manipulator robot or device, and wherein said robot is connected to said frame to manipulate said frame in a controlled manner.