A METHOD AND A SYSTEM FOR SELF-REPAIRING AN OBJECT

Abstract

The present invention relates to a method for self-repairing an object, wherein the object (O) comprises a matrix of a material in a continuous solid form, with optically resonant particles dispersed there within, and that has been made by fusing together particles and/or particulates of the material in a non-continuous solid form with heat transferred from the optically resonant particles that has been generated thereby when optically resonating induced by their exposure to building electromagnetic radiation. The method comprises exposing a damaged region (D) of the object (O) to repairing electromagnetic radiation (R) to be absorbed by the optically resonant particles that are dispersed therein to optically resonate to generate heat to fuse together portions of the matrix in thermal contact therewith. The system is adapted to implement the method of the invention.

Claims

1. A method for self-repairing an object, wherein said object comprises a matrix of a material in a continuous solid form with optically resonant particles dispersed there within, and wherein said matrix has been made by at least partially fusing together at least one of particles ands particulates of said material in a non-continuous solid form with heat transferred from said optically resonant particles that has been generated thereby when optically resonating induced by their exposure to building electromagnetic radiation, and wherein the method comprises exposing a damaged region of said object to repairing electromagnetic radiation to be absorbed by at least some of said optically resonant particles that are dispersed therein, to optically resonate to generate heat to at least partially fuse together portions of said matrix in thermal contact therewith.

2. The method of claim 1, wherein said optically resonant particles are made, and arranged within said matrix, to maintain their optical resonant properties to generate heat enough to at least partially fuse together those portions of said matrix in thermal contact therewith, for a plurality of times.

3. The method of claim 1, wherein said material is a thermoplastic material.

4. The method of claim 1, wherein said material is an elastomeric material.

5. The method of claim 1, wherein, in the object, both before and after performing the self-repairing, the optically resonant particles are dispersed in a substantially non-agglomerated and substantially non-self-sintered form within the material that is in a continuous solid form, including the self-repaired damaged region.

6. The method of claim 5, wherein said substantially non-agglomerated and substantially non-self-sintered form refers to the lack of a substantial agglomeration and substantial self-sintering referring to an agglomeration and self-sintering which causes a change in the absorption spectra of the optically resonant particles in the form of at least one of: at least one shift in one or more optical resonance peaks above or equal to five times the full-width at half maximum (FWHM); and at least a broadening of one or more optical resonance peaks above or equal to five times the FWHM.

7. The method of claim 1, wherein said optically resonant particles are coated with an anti-agglomeration coating.

8. The method of claim 7, wherein said anti-agglomeration coating is made to maximize at least one of thermal shape stability and to maximize thermal chemical stability.

9. The method of claim 1, wherein said damaged region includes at least one of the following damages or defects: a cut, a schism, a hole, a rough surface, and a morph alteration.

10. The method of claim 1, wherein said damaged region includes portions of the object that have been physically detached by a damage or defect, the method comprising bringing into physical contact said physically detached portions at least one of before and during their exposure to the repairing electromagnetic radiation.

11. The method of claim 1, wherein for a damaged region placed in an inner location of the object, the method comprises penetrating into the object with the repairing electromagnetic radiation up to said inner location so that the damaged region is exposed thereto.

12. The method of claim 1, wherein for an object or at least a damaged region thereof placed within water, the method comprises selecting a wavelength or sets of wavelengths, for the repairing electromagnetic radiation to which the damaged region is to be exposed, which fall within one of the optical transparency wavelength windows of water.

13. The method of claim 1, wherein said object is a three-dimensional object that has been manufactured using a layer-by-layer deposition process, by applying, over an already formed layer that includes said matrix with optically resonant particles dispersed there within, at least a further layer of said material in a non-continuous solid form with optically resonant particles already dispersed there within or subsequently provided thereon and dispersed there within, and exposing to building electromagnetic radiation the optically resonant particles provided on the further layer to make them optically resonate to generate heat to at least partially fuse together at least one of particles and particulates, of the material in a non-continuous solid form of the further layer, which are in thermal contact therewith.

14. A system for self-repairing an object, wherein said object comprises a matrix of a material in a continuous solid form with optically resonant particles dispersed there within, wherein said matrix has been made by at least partially fusing together at least one of particles and particulates of said material in a non-continuous solid form with heat transferred from said optically resonant particles that has been generated thereby when optically resonating induced by their exposure to building electromagnetic radiation, and wherein the system comprises a controllable electromagnetic radiation source configured and arranged for exposing a damaged region of said object to repairing electromagnetic radiation to be absorbed by some of said optically resonant particles that are dispersed therein to optically resonate to generate heat to at least partially fuse together portions of said matrix in thermal contact therewith.

15. The system of claim 14, further comprising: a monitoring mechanism configured and arranged for monitoring one or more parameters of at least the damaged region of the object, at least during its exposure to said repairing electromagnetic radiation, and generate corresponding monitoring signals; and a controller operatively connected to said monitoring mechanism to receive said monitoring signal, and to the controllable electromagnetic radiation source, said controller being made to control the operation of the controllable electromagnetic radiation source based on the received monitoring signals.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0083] In the following some preferred embodiments of the invention will be described with reference to the enclosed figures. They are provided only for illustration purposes without however limiting the scope of the invention.

[0084] FIG. 1 is a schematic representation of the system of the second aspect of the present invention, for an embodiment. FIG. 2 shows an object to be repaired by means of the method of the first aspect of the invention, for an embodiment for which the object has three damaged regions, identified as “damage 1”, “damage 2”, and “damage 3”.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0085] The system of the second aspect of the present invention is schematically shown in FIG. 1, and, as already explained above, is applied to the self-repairing of an object O that comprises a matrix of a material in a continuous solid form with optically resonant particles dispersed there within, wherein that matrix has been made by at least partially fusing together particles and/or particulates of said material in a non-continuous solid form with heat transferred from said optically resonant particles that has been generated thereby when optically resonating induced by their exposure to building electromagnetic radiation

[0086] The system of the second aspect of the invention comprises a controllable electromagnetic radiation source S configured and arranged for exposing a damaged region D of the object O to repairing electromagnetic radiation R to be absorbed by some of the optically resonant particles that are dispersed therein to optically resonate to generate heat to at least partially fuse together portions of the matrix in thermal contact therewith.

[0087] For the illustrated embodiment, the system also comprises: [0088] monitoring means M configured and arranged for monitoring one or more parameters of at least the damaged region D of the object O, at least during its exposure to said repairing electromagnetic radiation R, and generate corresponding monitoring signals; and [0089] a controller C operatively connected to the monitoring means M to receive said monitoring signals, and to the controllable electromagnetic radiation source S, said controller C being made to control the operation of the controllable electromagnetic radiation source S based on the received monitoring signals.

[0090] In the following, some experiments performed by the present inventors are described, for some working embodiments, to support the goodness and efficiency of the different aspects of the present invention.

[0091] Gold nanorods exhibiting a plasmon resonance peak with a full width at half maximum of about 100 nm and centered at about 850 nm, were synthesized and dispersed in ethanol at a concentration of 0.2 mg/ml. Then 1 L of such solution was mixed with 1 kg of TPU (thermoplastic polyurethane) powder (product name: ADSint TPU80) purchased from ADVANC3D Materials® GmbH. The mixture was left drying for 24 hr. resulting to a mixed material in which the gold nanorods are the optically resonant particles and the TPU powder is the matrix material referred above when describing the method and system of the present invention.

[0092] Then, the mixed material was transferred to an SLS-type 3D printer equipped with a 1 W 850 nm laser which acted as the source of the repairing electromagnetic radiation (808 nm) of the present the invention. Then, an object was manufactured by 3D printing, the shape of which is shown in FIG. 2, and having the dimensions indicated in the figure. It is noted that the object appeared to be highly flexible and to exhibit good elasticity. For the printing process the following parameters were used: 0.015 mm layer thickness, baseline temperature 80° C., 50 mm/s laser writing speed.

[0093] After the object was manufactured/printed and cleaned, it was damaged by cutting it in three areas of it as indicated in FIG. 2.

[0094] For fixing “damage 1”, the object was positioned in front of a second 808 nm laser source which acts as the controllable electromagnetic radiation source of the first and second aspects of the invention. An optical fiber with a waveguide at its tip was attached to the laser, which acts as an example of the optical control system of the second aspect of the invention, and the combination of the laser with the optical control system form, for an embodiment, the irradiation system of the system of the second aspect of the invention.

[0095] The object was specifically positioned as be able to have the laser beam exiting the waveguide directly illuminating the area of the object containing “damage 1”. In addition, the object was positioned by hand as to have its parts that surround “damage 1” (see FIG. 2) directly touching each other. For ensuring that these parts remain in good physical contact, two heavy pieces of metal were positioned on two opposing sides of the object as to prevent it from moving, these pieces of metal act as an example of an optional subsystem of the irradiation system of the system of the second aspect of the invention. The object with the laser and the rest of the irradiation system were enclosed in a black chamber for preventing exposure of the user to the laser beam. This plastic chamber is another example of an optional subsystem of the irradiation system of the system of the second aspect of the invention.

[0096] Within the black chamber there was also a video camera and a thermal camera for monitoring the structure, position, morphology and temperature of the object, these cameras act as examples of optional subcomponents of the second aspect of the invention. The laser was driven by a control power unit which also acts as an example of an optional subcomponent. The control unit and the cameras were controlled by a personal computer which also form part of the monitoring means of the system of the second aspect of the invention, for an embodiment.

[0097] When the object was positioned, the laser was turned on and its intensity was adjusted to about 3 W/cm.sup.2 as to cause heating of the area of the object being illuminated to about 130-150° C., as monitored by the thermal camera. The laser was left turned on for about 60 s, after which it was turned off and the object was left to cool down for 60 s. Then the object was removed and it appeared as repaired, meaning that the parts surrounding the area formerly containing “damage 1” have been sintered with each other and “damage 1” was no longer present. In addition, the part of the object formerly containing “damage 1”, exhibited good mechanical strength meaning that it could sustain without breaking apart mechanical forces applied by hand.

[0098] Then, the object was positioned in front of a LED array made of several 850 nm LEDs each of which was enclosed within its own individual plastic transparent cover, the LEDs and the plastic covers act as examples of controllable electromagnetic radiation sources and optical control system which in combination form an irradiation system of the second aspect of the invention. The object was more specifically positioned as to allow illumination of the object's areas containing “damage 2” and “damage 3”. Then the LED array was turned on for 60 s, and then it was tuned of. After this process, “damage 2” and “damage 3” had been repaired and disappeared.

[0099] The object was further positioned in front of a handheld light torch powered by batteries. The light of the torch was produced by a small LED array producing light of 850 nm wavelength. In front of the LED array the torch contained a set of plastic lenses. It was noticed that the object heats up when positioned in front of the torch. Therefore, the torch also acts an example of the irradiation system of the system of the second aspect of the invention.

[0100] A person skilled in the art could introduce changes and modifications in the embodiments described without departing from the scope of the invention as it is defined in the attached claims.