RestArt method: innovative high-precision mechatronic-based procedure for fragmented stone statues restoration

Abstract

Abstract The RestArt method is an innovative mechatronic-based procedure for high-precision reassembly of stone fragments intended to improve the restoration of ancient statues and architectural elements. The procedure comprises high-accuracy 3D laser scanning of two fragments positioned on the RestArt machine. After software simulated best-fitting of the two homologous fractured faces, the calculated roto-translation matrix is sent to the machine control system that moves one fragment to match the other one. The machine integrates a numeric-controlled moving drilling device for high-precision boring of the fractured surfaces at selected points for optimal rods insertion. This permits a very effective fixing of the fragments and allows multi-point fixing, which is practically impossible with conventional methods. Several stone specimens were experimentally recomposed through the RestArt and the traditional method. Then, they were compared in terms of mechanical resistance by shaking table tests, reproducing extreme strong-motion vibrations. The specimens recomposed through the RestArt method resulted less time-consuming and much more resistant to vibration excitation than the ones by traditional reassembly method. The RestArt method was applied to reassemble some original ancient statues currently exhibited at several Italian museums.