The present invention relates to a method and a system for creating prefabricated foundations ready to be driven into the ground, such foundations possess the fundamental characteristic of increasing the size of the reacting pressure "bulb" in the ground compared to the currently known fixed foundations, in fact, compared to a traditional foundation driven into the ground, in which the area of the section of the foundation is constant, the present invention it allows to increase this section area and this happens automatically during the insertion, this effect is obtained thanks to the opening during the insertion of particular moving parts that increase the area of the reactive surface with the ground the insertion and increase the reactant surface allowing to increase yes a the foundation buckling load, and the lateral load it can withstand. In practice, after a first driving of the foundation, by acting on an release device, moving parts are freed which open into the ground as the foundation is driven. The present invention allows, for soils with slight slopes, to avoid the leveling of the soil by means of mechanical excavations, the leveling is obtained by acting on the height adjustments of the plates placed on the terminal part of the foundations. The present invention makes it possible to create foundations much lighter than those existing in the state of the art, with the same final performance, this feature allows easier transport to the installation site. The greater speed of installation, the lower weight, allow to have a lower cost compared to the already known driving foundations. At the current state of There are prefabricated steel foundations, put in place by driving or roto-driving but which do not have the characteristic of increasing their size during the driving itself, or they can increase it but in a limited way, one type is the classic foundation with a constant section driven into the ground, the other consists of a large screw that is literally screwed into the ground. In particular for the current state of the art. Still with reference to the state of the art, with reference to the patent n.US5975808A of 02-11-1999, the moving parts that are inserted into the ground and indicated in the figures of this patent n.US5975808A with the numbers 44 and 24 have limitations in their lengths consequently limiting the surface in contact with the ground and consequently limiting considerably the bearing capacity of the foundation, this limitation of the length of the moving parts is due to the evident fact that during their downward movement to enter the ground the moving parts come out of the sheaths that contain them by slipping into special slots obtained on the same sliders, then a linear movement and a rotation are combined together, this combined movement, being the same moving parts contained in the sliders, can take place, without the moving parts getting stuck with the sliders during movement, only for certain lengths of the moving parts themselves, in fact the length of the moving parts The ones that slip into the ground cannot be greater than the diameter of the sheath or in any case the width of the sheath itself, beyond this length it would be prevented from rotating and therefore the moving parts from coming out of the sheath. The present invention solves and overcomes the problems and limitations of patent D1 n.US5975808A, in fact for the same foundation section area without the moving parts, since the moving parts are external to the sheaths, they have no length limitations being able to rotate at will, therefore the present invention constitutes an inventive novelty, allowing to have greater lift and efficiency with the same foundation section area compared to the solution of patent D1 no. US5975808A, moreover the time to put the foundation in place is shorter as the opening of the wings occurs automatically during the driving of the foundation into the ground while in patent no. US5975808A a further step is required for the separate typing of the moving parts. With reference to patent D2 n. 2005/074298 A1, in which the foundation is driven into the ground by rotation by means of a helical element placed on the tip of the foundation, the section during screw driving remains constant, also in this case the present invention constitutes an inventive novelty in fact with the same The sectional area of the foundation increases the load capacity on the foundation itself, this occurs due to the effect of the moving parts, which increase the section of the foundation during the insertion. Referring then to the patent D3 n.US3774361 of 11/27/1973, the present invention constitutes an inventive novelty overcoming the limits set by this patent n.US3774361 due to the fact that the lift reaction takes place in the opposite direction to that of driving the foundation, for this reason, patent No. US3774361 is inapplicable to foundations for manufactured articles. With the present invention there is also the advantage of being able to recover the foundation by simply removing it from the ground. The insertion into the ground takes place using known techniques. In accordance with the present invention, these objects and others are achieved by a system for the construction of prefabricated foundations to support products of any kind and type made of steel to be placed by driving with beating according to known techniques on non-rocky soils; the single foundation is composed of a first piece (1) consisting of a hollow steel section with a square section having the head formed by a plate (26) of adequate thickness to be able to house a threaded hole (7) of adequate diameter and strength capable of supporting the support plate (20) on which the overlying articles (21 ) are placed, this plate (21) is adjustable in height by means of the screw (22); the first piece (1 ) constituting part of the foundation, it is grafted through a suitable coupling socket (8) to a second hollow steel piece (2) with the same section as the previous piece (1); the union of the first piece (1) to the second piece (2) is ensured by the pins (9) inserted between the first piece (1) and the second piece (2) passing through the relative coupling socket (8) these pins are blocked from the cotter pins (10); the second piece (2) is inserted into the coupling socket (8) on a third piece also made of box-like steel (3) having the same section as the previous pieces (1 ) (2); the union between the second piece (2) and the third piece (3) fig. 1 is ensured by pins (9) existing between the second piece (2) and the third piece (3) which pass through the relative coupling socket (8) these pins are locked in their position by special split pins (10); the third piece (3) is provided with two movable rotating wings (12) around suitable hinges (13); the movable parts (12) are locked in a parallel position with respect to the vertical of the part (3) by means of the stops (15) inserted in the grooved piece (14); these stops (15) are connected to the release cables (22); the springs (16) are located between the parts (21 ) and the wings (12), these previously compressed springs apply a thrust force according to their axis on the wings (12); the wings (12) once the stops (15) have been removed by pulling the release cables (22) can rotate around the pins (13) due to the thrust of the springs (16); the piece (3) is equipped with a driving point (4) blocked on the piece (3) by the pin (9) and the cotter pins (10); the piece (3) complete with all its parts is at least one for a single foundation. These purposes are also achieved with a method for the construction of prefabricated foundations to support products of any kind and type made of steel to be placed by driving with beating on non-rocky soils characterized by the fact of including several stages of assembly of the foundation; the first phase is characterized by the beating of the assembled foundation (6) to start its penetration into the ground, in this phase the foundation is complete with all its parts except for the part relating to the plate (20) with its screw (22), the assembled foundation (6) is made up of pieces nos. (1 ), (8 ), (2), for at least one piece (3) with its tip (4), the piece (3) is complete with all its parts such as the movable wings (12) held in closed position by the blocks (15), the release system consisting of the cables (22), the springs (16); in a second phase, when the foundation has been driven into the ground for a certain height such as to cover part no. (3), the wings (12) are unlocked by pulling the blocks (15) upwards with the aid of the cables (22); in a third phase, the foundation insertion continues and the unlocked wings (12) begin to rotate automatically, without further subsequent phases or operations, opening and slipping into the ground due to the simultaneous effect of the foundation insertion downwards as shown in the arrow (23 ), by continuing the piling, one arrives at a predetermined depth of piling of the foundation in which the total opening of 45 ⁰ (18) of the wings (12) is obtained, thus obtaining the predetermined increase in the final lift of the foundation; with a further step the plate (20) is screwed through the threaded screw (22) to the head (1) of the foundation and screwed until the desired height adjustment is obtained to later rest the artifact (21 ). The characteristics and advantages of the present invention will become evident from the following description of one of its practical embodiments, illustrated by way of non-limiting purposes in the accompanying drawings, according to a first embodiment, in which: Figure 1 schematically shows how the single foundation, essentially from the pieces (1), (2), (3), and (4) which are joined together with the pins (9) and the cotter pins (10) to form the single piece (6). Figure 2 shows the single foundation with the moving parts (12) by means of the springs (16), and the head of the foundation (2 =) adjustable in height by means of the screw (22) is also shown. Figure 3 shows a section of the part of the foundation having the moving parts, in that figure the movable parts (12) are shown in the closed position, in the same figure 3 in addition to the movable parts (12) that open during insertion, the hinges (13) are also drawn which allow the rotation of the parts (12) and the springs (16) that activate the initial movement of the parts (12), in the same figure there are the lock-release devices (15) of the rotation of the parts (12), the release devices are activated by pulling the cable upwards (22), in Figure 3 there is also a reinforcement part 21 which serves to limit the rotations of the moving parts (12). Figure 4 shows a sectioned view of the piece of the foundation having the moving parts (12) in the final open position, the wings (12) open during the insertion first due to the thrust of the springs (16) and then due to the thrust of the the ground itself, as seen in Figure 4, the part (21) acts as a contrast and prevents further rotation of the parts (12). Figure 5 shows the main driving phases of the foundation which takes place by beating in the direction of the arrow (23), it can be seen that in the intermediate driving phase the li (12) begin to open with a first angle (24) and subsequently by driving when completed, the same wings (12) are completely open at an angle (18), the same figure 5 indicates the adjustable support part (20) positioned with the foundation completely fixed.