Automated apparatus and method for engraving objects

Abstract

An apparatus for automatically polishing an object having multiple facets includes a polishing wheel, a robotic arm, a sensor, and a controller. The robotic arm positions the object in contact with the polishing wheel. The sensor senses polishing-related parameters during polishing of the object with the polishing wheel. The controller operates the robotic arm to rotate the object about an axis perpendicular to the polishing wheel, receives sensing signals from the sensor in different directions on the object during polishing, and selects a polishing direction from the different directions based on the sensing signals.

Description

[0001] Related Applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 987,875, filed March 11, 2020, the contents of which are incorporated herein by reference in their entirety.

[0003] TECHNICAL FIELD AND BACKGROUND

[0004] In some embodiments of the invention, the invention relates to automated apparatus and methods for faceting of objects, and more particularly, but not exclusively, to an automated apparatus and method for faceting of diamonds.

[0005] Traditionally, the faceting of objects such as diamonds and other gemstones is done manually using a polishing wheel, for example a polishing wheel "scaif". As is well known, such a manual process is both time consuming and expensive. Computer methods are known which can be used to assist in planning the polishing of a gemstone rough. A three-dimensional (3D) model of the gemstone rough is typically generated and a target polished gemstone can be defined in the 3D model. However, after the plan is in place, the subsequent polishing process, by which each facet of the cut and polished gemstone is cut and polished, is typically performed manually so that the process can be monitored and adjusted as necessary.

[0006] The faceting process can introduce artifacts on the surface of the gemstone, for example pits, scratches and polishing lines. In addition, natural inclusions within the gemstone can come to the surface during the polishing process. Human intervention is typically required to adjust the faceting process to overcome these obstacles. Inaccuracy in the polishing process itself can also require human intervention. Friction between the gemstone and the polishing wheel can generate high temperatures and can affect the accuracy of the polishing. When polishing a diamond, due to the crystal structure of the diamond, certain polishing directions can be more resistant to polishing than others. Polishing in an unfavorable polishing direction can impede the polishing ability and can affect the polishing result. Repeated monitoring and adjustment is required to achieve a high quality final product. For an automated process to replace the traditional manual polishing method, a high precision faceting is required which is able to adjust the faceting process throughout the process.

[0007] International patent application publication no. WO / 2019 / 042850 entitled "Improved method for controlling polishing of gemstones" the contents of which are incorporated herein by reference discloses a method for controlling polishing of gemstones. The method includes obtaining a three-dimensional model of a gemstone; securing the gemstone in a holder with an initial facet to be polished aligned; obtaining at least one image of the initial facet while the gemstone is in the holder such that a profile of the initial facet can be determined from the at least one image. Based on the obtained at least one image and the obtained three-dimensional model, at least a first setting parameter of a first planned facet located between the initial facet and a desired final polished facet is determined. The holder is set for obtaining a polished gemstone having a polished facet approximating the first planned facet. At least one polished image is obtained while the gemstone is in the holder. Based on the obtained at least one image of the polished facet and the three-dimensional model, at least a further setting parameter of a further planned facet is determined. The holder is set to obtain a polished gemstone having a polished facet approximating the further planned facet.

[0008] International patent application publication no. WO / 2019 / 043488 entitled "An automated gemstone polishing robot" the contents of which are incorporated herein by reference describes a fully automated gemstone polishing robot. The automated gemstone polishing robot includes a gemstone polishing unit, an image capturing unit, and an image processing unit. The image processing unit is executed by one or more processors and analyzes images of a gemstone for one or more gemstone parameters. The image processing unit compares the one or more analyzed gemstone parameters to one or more predetermined gemstone parameters to generate a feedback signal to transmit to the gemstone polishing unit. The gemstone polishing unit includes a gemstone holding unit for supporting a gemstone in contact with an abrasive surface and polishes the gemstone in a plurality of iterations based on the feedback signal. SUMMARY

[0009] According to an aspect of some example embodiments, there is provided an automated apparatus and method for faceting an object in a fully automated process with improved precision and / or control. In some example embodiments, the automated apparatus and method are additionally configured for reducing the time taken to facet the object. In some example embodiments, the automated apparatus and method are configured to detect a suitable polishing direction. In some example embodiments, the automated apparatus and method are configured to provide an authenticated trajectory for identifying the object throughout the faceting process. In some example embodiments, the apparatus and method are provided to generate an automatic signature key for a multi-faceted object.

[0010] According to an aspect of some example embodiments, there is provided an apparatus for automatically faceting an object, comprising: a polishing wheel; a robotic arm configured to position the object in contact with the polishing wheel; a sensor configured to sense a polishing-related parameter during polishing of the object by the polishing wheel; a controller configured to: operate the robotic arm to rotate the object about an axis perpendicular to the polishing wheel; receive, during the polishing, sensing signals from the sensor from different directions of the object; and select, from the different directions, a polishing direction based on the sensing signals.

[0011] Optionally, the controller is configured to rotate the object while maintaining contact between the object and the polishing wheel, and to continuously receive the sensing signals during the rotation.

[0012] Optionally, the polishing direction selected by the controller is a direction in which the polishing-related parameter has a predetermined identifiable characteristic.

[0013] Optionally, the sensor is configured to sense an amplitude or frequency of vibrations associated with contact between the object and the polishing wheel during polishing, and wherein the selected polishing direction is a direction in which the amplitude or frequency of vibrations exhibits a predetermined identifiable characteristic.

[0014] Optionally, the sensor is selected from a group consisting of: a microphone, a displacement sensor, and an accelerometer.

[0015] Optionally, the sensor is a temperature sensor configured to sense heat dissipated during polishing based on contact between the object and the polishing wheel, and wherein the selected polishing direction is a direction in which the temperature exhibits a predetermined identifiable characteristic.

[0016] Optionally, the apparatus comprises at least one additional sensor configured to sense an additional polishing-related parameter during polishing, and wherein the controller is configured to select the polishing direction based on the sensing signals from the sensor and additional sensing signals from the additional sensor.

[0017] Optionally, the controller is configured to repeat the operating, receiving, and selecting for each facet on the object.

[0018] Optionally, the apparatus comprises an imaging system, wherein the controller is configured to operate the robotic arm to manipulate the object to a focal plane of the imaging system, and to operate the imaging system to intermittently image the facets of the object as the polishing progresses.

[0019] Optionally, the controller is configured to automatically operate the robotic arm to change the polishing direction based on image data from the imaging system.

[0020] According to an aspect of some embodiments, there is provided a method for automatic faceting of an object, the method comprising: positioning the object in contact with a polishing wheel; rotating the object about an axis perpendicular to the polishing wheel with the robotic arm; receiving sensing signals from sensors of different orientations of the object during polishing, wherein the sensors are configured to sense a polishing-related parameter; selecting a polishing orientation from the different orientations according to the sensing signals.

[0021] Optionally, the method comprises maintaining contact between the object and the polishing wheel while rotating the object, and receiving continuous sensing signals during rotation.

[0022] Optionally, the selected polishing orientation is a direction in which the polishing-related parameter has a predetermined identifiable characteristic.

[0023] Optionally, the sensors are configured to sense vibrations, sound, displacement, heat dissipation or current supplied to the robotic arm during polishing while the object is in contact with the polishing wheel.

[0024] Optionally, the method comprises sensing at least one additional polishing-related parameter during polishing and selecting a polishing orientation based on the polishing-related parameter and the additional polishing-related parameter.

[0025] Optionally, the positioning, rotating, receiving and selecting are repeated for a plurality of facets on each object.

[0026] Optionally, facets of the object are imaged intermittently during polishing, wherein the imaging is performed while the object is mounted on the robotic arm.

[0027] Optionally, the method comprises changing the polishing orientation based on image data from the imaging system.

[0028] According to an aspect of some embodiments, there is provided a method for automatic faceting of an object, the method comprising: polishing the object with a polishing wheel while: sensing at least one polishing-related parameter; and in a closed loop control, adjusting at least one operational parameter in response to a value of the sensed polishing-related parameter, the operational parameter selected from the group consisting of: rotational speed of the polishing wheel, contact pressure of the object on the polishing wheel and trajectory position of the object on the rotating wheel.

[0029] Optionally, the adjustment is selected to control a material removal rate for removing material from the object.

[0030] Optionally, the method comprises terminating polishing when the value of the parameter is within a predetermined range.

[0031] According to one aspect of some example embodiments, an apparatus for automatically faceting an object is provided, comprising: a polishing wheel; a robotic arm configured to position the object in contact with the polishing wheel; a sensor configured to sense at least one polishing-related parameter during polishing of the object by the polishing wheel; and a controller configured to responsively adjust at least one operating parameter during polishing and in closed-loop control, the operating parameter being selected from current flowing to the robotic arm, rotational speed of the polishing wheel, and a track used on the polishing wheel.

[0032] Optionally, there are at least two polishing-related parameters, one of which is a vertical position of the object.

[0033] Optionally, the at least one polishing-related parameter is selected from: vibrations, sounds, displacements, heat dissipation, and pressure applied to the object during the polishing process related to the contact between the object and the polishing wheel.

[0034] Optionally, at least one polishing-related parameter is the current supplied to the robotic arm, which is related to the pressure exerted by the object on the polishing wheel.

[0035] Optionally, the method includes obtaining a computer-readable medium storing a lookup table with multiple entries, each entry including a value of a polishing-related parameter and at least one associated operating parameter; searching the lookup table for a range of entries corresponding to the sensed polishing-related parameters; and setting at least one operating parameter based on the corresponding value in the entry.

[0036] According to one aspect of some example embodiments, a method for automatically faceting an object is provided, the method comprising: operating a robotic arm to rotate the object about an axis perpendicular to a polishing wheel during the polishing of a first facet of the object; sensing polishing-related parameters during the polishing process; identifying one to four directions of the robotic arm in which the polishing-related parameters have predefined identifiable features, thereby identifying one to four corresponding candidate directions for polishing; repeating the operation, sensing, and identification for one or more additional facets of the object until at least four candidate directions for polishing are identified; and using the at least four candidate directions to select a polishing direction for the additional facets of the object.

[0037] Optionally, the method includes predicting the crystal axis of the object based on at least four candidate polishing directions.

[0038] Optionally, the method includes defining orthogonal projections of at least one crystal axis onto an additional surface of the object based on prediction.

[0039] Optionally, the method includes updating the prediction of the crystal axis based on sensing polishing-related parameters, while polishing at least one facet of the object in addition to one or more additional facets.

[0040] Optionally, the method includes imaging at least one face of the object between polishing intervals and updating the prediction of the crystal axis based on the image data from the imaging.

[0041] According to one aspect of some example embodiments, an apparatus for automatically faceting an object is provided, comprising: a laser cutting device configured to cut the object; a polishing wheel configured to polish the object; a robotic arm configured to hold the object; and a controller configured to operate the robotic arm to position the object relative to the laser cutting device to remove a first portion of the object by laser cutting, and subsequently operate the robotic arm to position the object relative to the polishing wheel for removing a second portion of the object by polishing without dislodging the object from the robotic arm, wherein the first portion and the second portion are selected to reduce the time required to polish the object.

[0042] Optionally, the device includes a processor; and an imaging system configured to capture images of an object mounted on a robotic arm, wherein the controller is configured to operate the robotic arm to position the object relative to the imaging system, and wherein the processor is configured to construct a three-dimensional model of the object held on the robotic arm based on the images, and to define the boundaries of the first portion and the second portion based on the three-dimensional model.

[0043] Optionally, the amount of material included in the first part is greater than the amount in the second part.

[0044] According to one aspect of some example embodiments, a method for automatically faceting an object is provided, the method comprising: operating a robotic arm on which the object is mounted to position the object relative to a laser cutting device to remove a first portion of the object by laser cutting; and then, without separating the object from the robotic arm, operating the robotic arm to position the object relative to a polishing wheel to remove a second portion of the object by polishing, wherein the volume of the first portion is larger than that of the second portion.

[0045] Optionally, the method includes operating a robotic arm to position an object relative to an imaging system configured to define a three-dimensional model of the object, and defining the boundaries of the first and second portions based on the three-dimensional model, wherein the definition is performed prior to laser cutting and polishing; and holding the object on the robotic arm after imaging and during polishing and laser cutting.

[0046] According to one aspect of some example embodiments, an apparatus for automatically faceting an object is provided, comprising: a polishing wheel; a press-pot marked with an identification code for holding the object, the identification code identifying the object; a robotic arm configured to hold the press-pot and position the object in contact with the polishing wheel during polishing; an identification code reader for reading the identification code when the robotic arm holds the press-pot; and a controller configured to acquire instructions on a computer-readable medium for polishing the object based on identifying the identification code on the press-pot and controlling the operation of the apparatus for polishing the object according to the instructions.

[0047] Optionally, the device includes an imaging system configured to capture images of an object on the robotic arm and define a three-dimensional model of the object based on the images, wherein the identification code reader is integrated with the imaging system.

[0048] Optionally, the pressure vessel includes: a snap-fit ​​portion configured to clamp the object; a base portion configured to be mounted on a robotic arm for holding the pressure vessel and the object it is fastened to; and an intermediate portion extending from the base portion to the snap-fit ​​portion, wherein the intermediate portion includes a plurality of holes formed thereon; and a plurality of plugs configured to selectively fit into one or more of the plurality of holes, wherein the selectively fitted plugs define the identification code.

[0049] According to one aspect of some example embodiments, a method for automatically faceting an object is provided, comprising: mounting the object on a pressure vessel, wherein the pressure vessel includes an identification code configured to identify the object; operating a robotic arm to position the pressure vessel with the object toward a reader configured to read the identification code; obtaining instructions based on the identification code for polishing the object on a computer-readable medium; and operating the robotic arm and a polishing wheel during polishing to polish the object according to the instructions.

[0050] Optionally, the reader is integrated into an imaging system configured to capture images of objects on the robotic arm and to define a 3D model of the objects based on the images.

[0051] According to one aspect of some example embodiments, a method is provided for defining a gemstone signature key for a polished gemstone, the method comprising: determining the geometry, three-dimensional position, and morphology of each of a plurality of facets of the gemstone using an imaging system of an automated polishing apparatus; generating a gemstone signature key based on the geometry, three-dimensional position, and morphology; and storing the key in a computer-readable medium.

[0052] According to one aspect of some example embodiments, a method for faceting an object is provided, comprising: acquiring a three-dimensional model of the object and a target three-dimensional shape having a plurality of facets; for each plurality of facets of the target shape, calculating, based on the model, an amount of material to be removed from the object to form the facets; generating a sequential list of the plurality of facets in descending order of the calculated amount; and performing a protocol for polishing the plurality of facets of the object according to the sequential list.

[0053] According to one aspect of some example embodiments, a method for faceting an object is provided, comprising: acquiring a three-dimensional model of the object and defining a target three-dimensional shape for a plurality of facets; for each of the plurality of facets of the target shape, calculating the projection of the crystal axis of the object onto the facet based on the model; generating a sequential list of the plurality of facets in descending order of the calculated projection amounts; and executing a protocol for polishing the plurality of facets according to the sequential list.

[0054] According to one aspect of some example embodiments, a method for faceting an object is provided, comprising: acquiring a three-dimensional model of the object and defining a target three-dimensional shape for a plurality of facets; for each of the plurality of facets of the target shape, calculating, based on the model, the projection of the crystal axis of the object onto the facet, the amount of material to be removed from the object to form the facet, and a manufacturing fraction as a weighted combination of the projection and the amount of material removed; generating a sequential list of the plurality of facets in descending order of the calculated fractions; and executing a protocol for forming the plurality of facets according to the sequential list.

[0055] Optionally, the method includes forming at least two facets of an object using an automated polishing device; sensing polishing-related parameters during the forming process; predicting the crystal axis of the object based on the sensing; wherein a sequential list of multiple facets is also generated based on the prediction.

[0056] Optionally, the method includes using the forming intermittently to image the object to determine the geometry and morphology of the facets being formed, and updating the sequential list based on the imaging.

[0057] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. While similar or equivalent methods and materials to those described and materials herein may be used in the practice or testing of embodiments of the invention, exemplary methods and / or materials are described below. In case of conflict, the patent specification (including definitions) shall prevail. Furthermore, these materials, methods, and examples are illustrative only and are not necessarily restrictive. Attached Figure Description

[0058] This document describes some embodiments of the invention by way of example only, with reference to the accompanying drawings. Detailed reference is now made to the drawings, with emphasis placed on the fact that the details shown are exemplary and for the purpose of illustrative discussion of embodiments of the invention. In this regard, it will become apparent to those skilled in the art from the description taken in conjunction with the drawings how embodiments of the invention can be practiced.

[0059] In the attached diagram:

[0060] Figure 1 This is a simplified schematic diagram of an automatic faceting apparatus according to some example embodiments;

[0061] Figure 2 This is a simplified schematic diagram of an example imaging system for an automated faceting device according to some example embodiments;

[0062] Figure 3 This is a simplified flowchart of an example method for generating a 3D model of a faceted object according to some example embodiments;

[0063] Figure 4A , 4B 4C and 4C are simplified diagrams depicting three sets of example instructions for forming the same plurality of facets on an object, based on some example embodiments;

[0064] Figure 5 This is a simplified flowchart of an example method for generating a sequential list of facets on an object whose chemical structure is a lattice, based on some example embodiments.

[0065] Figure 6 This is a simplified flowchart of an example method for selecting the orientation of facets on a polishing wheel during polishing, according to some example embodiments;

[0066] Figure 7A and 7B This is an example diagram illustrating the output of a sensor that senses polishing-related parameters when an object rotates about an axis perpendicular to the polishing wheel during polishing, according to some exemplary embodiments.

[0067] Figure 8A and 8B This is a simplified diagram illustrating an example crystal axis related to the facets of an object according to some example embodiments;

[0068] Figure 9 This is a simplified flowchart of an example method for predicting the crystal axis of an object, based on some example embodiments;

[0069] Figure 10 This is a simplified flowchart of an exemplary method for adjusting polishing during operation using an automated polishing device, according to some exemplary embodiments.

[0070] Figure 11This is a simplified flowchart of an exemplary method for adjusting polishing based on image data captured by an automated polishing device, according to some exemplary embodiments.

[0071] Figure 12 This is a simplified schematic diagram based on some example embodiments, illustrating two example differences in the modeling geometry of the facets and the facet geometry that may occur during faceting;

[0072] Figure 13 This is a simplified flowchart of an example method for detecting and recording object parameters at the end of the faceting process;

[0073] Figure 14A This is a simplified schematic diagram of an example automated faceting apparatus including a laser cutting station and a polishing station, according to some example embodiments;

[0074] Figure 14B This is a simplified schematic diagram of a laser cutting station according to some example embodiments;

[0075] Figure 15 This is a simplified flowchart of an example method for faceting an object by combining laser cutting and polishing according to some example embodiments;

[0076] Figure 16 These are example pressure vessels for holding objects according to some example embodiments; and

[0077] Figure 17 This is a simplified flowchart of an example method for identifying objects using pressure can identification codes, based on some example embodiments. Detailed Implementation

[0078] In some embodiments, the present invention relates to automated apparatus and methods for polishing faceted objects, and more specifically, but not exclusively, to automated apparatus and methods for polishing diamonds.

[0079] Before explaining at least one embodiment of the present invention in detail, it should be understood that the invention is not necessarily limited in its application to the construction details and arrangements of the components and / or methods set forth in the following description and / or illustrated in the drawings and / or embodiments. The invention can have other embodiments or can be practiced or performed in various ways.

[0080] According to some example embodiments, the apparatus and method provide an automated method for detecting a favorable polishing orientation. The suitable polishing orientation of a facet can be detected based on sensing one or more polishing-related parameters in different directions on the facet of the polishing wheel. Optionally and preferably, the polishing-related parameters provide an indication of the material removal rate, and the suitable polishing orientation is one with a relatively high rate and / or a peak material removal rate.

[0081] In some exemplary embodiments, the apparatus and method provide on-the-fly adjustment of operating parameters during polishing via closed-loop control. In some example embodiments, the closed-loop control is configured to maintain a stable, controlled, and / or constant rate of material removal on the facet as the polishing depth and facet surface area increase. Optionally, the rotational speed of the polishing wheel, the contact pressure of the object on the polishing wheel, and / or the trajectory position of the object on the rotating wheel are controlled in real time.

[0082] According to some example embodiments, the chemical structure of the object is a crystal lattice, and the apparatus and method are configured to predict the crystallographic axes of the crystal based on a trial-and-error process performed on one or more facets of the object. In some example embodiments, the crystallographic axes are inferred based on at least four suitable polishing directions sensed through the trial-and-error process. According to some exemplary embodiments, one orthogonal projection of the crystallographic axis onto a facet is selected as a suitable polishing direction for the facet.

[0083] According to some example embodiments, the device includes laser cutting and polishing capabilities and a controller configured to operate a robotic arm to position the object relative to the laser cutting equipment, thereby removing a first portion of the object by laser cutting, and subsequently operate the robotic arm to position the object relative to the polishing wheel to remove a second portion of the object by polishing without detaching the object from the robotic arm. Optionally, integrating laser cutting into the faceting process can significantly reduce the processing time required for faceting.

[0084] According to some example embodiments, the apparatus and method are configured to maintain an authentication trail for object recognition throughout the faceting process, based on a series of images captured during the faceting process. The authentication trail preferably includes sufficient information to identify the original, pre-polished object during and after the polishing process. The authentication trail can be, for example, in the form of a library of descriptors associated with the object, which describes the polishing process once polished, optionally and preferably the overall polishing process. The descriptors can be in the form of digital images and / or computer-rendered shapes and / or computer-rendered coordinates. In some embodiments of the invention, the descriptor library includes a set of descriptors for each facet formed by the apparatus, wherein each set of descriptors is ordered chronologically and describes the evolution of the shape of the individual faces during the formation process by the apparatus.

[0085] In some example embodiments, the press-pot holding the object includes an identification (ID) code, and a controller is configured to receive instructions on a computer-readable medium for polishing the object based on the identification code on the press-pot.

[0086] According to some example embodiments, the apparatus and method are configured to calculate a sequential list based on which the object is faceted. In some example embodiments, the sequential list is defined to reduce the processing time required for faceting. Optionally, processing time can be reduced by minimizing the joint movements of the robotic arm during faceting. Optionally, multiple parameters are considered when determining the polishing sequence. Non-limiting examples of these parameters include the volume of material to be removed, the crystal orientation relative to the facets to be polished, and the location of artifacts detected on or in the object surface.

[0087] According to some example embodiments, the apparatus and method are configured to generate a signature key for a polished object based on the geometry of each facet, the 3D position of each facet, and the morphology of the facet. Unlike verifying the authentication path of the polished object from the original object by linking the original object to an authentication trajectory of the polished object through a step of recording the polishing process, the signature key only describes the shape and morphology of the polished object. In some embodiments of the invention, the signature key also includes the object's grade (e.g., cut grade, polishing grade, symmetry grade). Optionally, the object's grade is generated separately.

[0088] According to some example embodiments, the device includes an inspection station having an imaging system and an image processor. According to some example embodiments, the imaging system includes a telecentric imaging system and a microscopic imaging system, and the image processor includes circuitry configured to process images captured by both the telecentric imaging system and the microscopic imaging system to generate a 3D model of the object. Optionally and preferably, the facets of the object are also inspected during the automated faceting process. According to some example embodiments, the 3D model is generated using the telecentric imaging system based on shadow modeling, and optionally refined based on selected images captured by the microscopic imaging system. Optionally and preferably, the image processor is also configured to classify artifacts detected on the surface of one or more facets. Optionally and preferably, the 3D model is generated when the object is mounted on the robotic arm, such that the generated model is defined using the coordinate system of the device. In some example embodiments, registration is performed between the generated 3D model and the received model when the 3D model of the object and / or the target model of the object defining the faceting plan are received along with the object. Optionally and preferably, registration is performed at the imaging station at the start of the automated process.

[0089] In some example embodiments, during automated faceting, the robotic arm is configured to move the object to an inspection station between polishing iterations to inspect the formed facets and optionally, and preferably, update the generated 3D model of the object. According to some example embodiments, at the end of the automated faceting process, the robotic arm again moves the object to the inspection station for a final inspection. In some example embodiments, the final inspection includes defining the object's grade (e.g., cut grade, polish grade, symmetry grade) based on image data captured using an imaging system. In some example embodiments, the final inspection includes generating a signature key based on the image data captured using an imaging system. Optionally and preferably, but not necessarily, the signature key uniquely identifies the object.

[0090] Figure 1 This is a simplified schematic diagram of an automated faceting apparatus 100 according to some example embodiments. The automated faceting apparatus 100 includes a robotic arm 110 configured to hold an object 10 during faceting, and a polishing station 121 including a polishing wheel 120 for polishing the object 10. Optionally, the automated faceting apparatus 100 includes an imaging station 131, which includes an imaging system 130 having image processing capabilities for inspecting the object 10. Figure 2An example imaging system is illustrated. In some embodiments of the invention, the automated faceting device 100 includes one or more sensors 140 for sensing polishing-related parameters. A controller 150 is optionally and preferably configured to control a robotic arm 110 to move an object 10 between a polishing station 121 and an imaging station 131, and is also optionally and preferably configured to control the operation of the automated faceting device 100 based on outputs from the sensors 140 acquired during polishing and / or based on image data acquired at the imaging station 131. The controller 150 is configured to coordinate the operation of the robotic arm 110 with each polishing station 121 and imaging station 131, as well as the sensors 140. The controller 150 is preferably a computerized controller and may include processing and memory capabilities, and may also communicate with a computing device 151 including processing capabilities, memory, and a user interface capability. In some embodiments of the invention, the controller 150 includes dedicated electronic circuitry configured to perform one or more of the operations described herein.

[0091] The robotic arm 110 can provide motion with multiple degrees of freedom, such as 4-6 degrees of freedom. In some example embodiments, the robotic arm 110 is configured for both gross movement capability and fine movement capability in one or more directions. Gross movement capability is useful for moving the object 10, such as moving it between polishing station 121 and imaging station 131. Fine movement capability is useful, for example, for orienting the object during high-resolution polishing and inspection, such as linear movement with submicron resolution (e.g., 0.01-0.9 μm resolution) and millimeter resolution (e.g., 0.01-10 μm resolution). -3 -0.9·10 -3 (resolution of degrees) is used for rotational motion. Optionally and preferably, the robotic arm 110 is mounted on a track 111 and actuated to move along the track 111 between the polishing station 121 and the imaging station 131. The object 10 is optionally and preferably mounted on the robotic arm 110 having a pressure vessel 60. In some exemplary embodiments, the pressure vessel 60 is marked with an identification (ID) code 61 to identify the object 10. Representative examples of identification codes applicable to exemplary embodiments of the present invention are provided below.

[0092] Sensor 140 may be mounted on robotic arm 110 and / or pressure tank 60 and / or polishing wheel 120. One or more sensors 140 may be remotely sensed without being mounted on any of the robotic arm 110, pressure tank 60, and polishing wheel 120. Sensor 140 may include, for example, one or more vibration sensors, such as accelerometers, microphones, temperature sensors, and displacement sensors. Encoders may be used to sense displacement, such as displacement encoders configured to sense the height of object 10 along the Z-axis during polishing. Alternatively, dedicated encoders may also be used to sense displacement in the X and / or Y directions. In some example embodiments, sensor 140 includes one or more sensors configured to sense current supplied to robotic arm 110 and / or polishing wheel 120. The current represents the friction generated between object 10 and polishing wheel 120 during polishing, and the pressure applied by object 10 to polishing wheel 120 during polishing. In some embodiments of the invention, controller 150 is configured to analyze the current and obtain friction and / or pressure. Optionally, sensor 140 includes one or more image sensors configured to capture images during polishing.

[0093] According to some example embodiments, robotic arm 110 positions and aligns object 10 in imaging station 131 prior to the polishing process to generate a 3D model of object 10. According to some example embodiments, the 3D model of object 10 is detected when object 10 is mounted on robotic arm 110. Instructions for faceting object 10 can then be defined based on the coordinate system of automated faceting device 100. Optionally, the instructions can be based on a target model received associated with the object, on general guidelines related to the desired size and shape for faceting, and / or can be generated automatically at imaging station 131. During polishing, robotic arm 110 is optionally and preferably configured to repeatedly toggle object 10 between polishing station 121 for polishing and imaging station 131 for inspection. Optionally, the defined 3D model can be updated with each inspection or multiple inspections. Optionally and preferably, each facet is formed over multiple polishing iterations, and robotic arm 110 is configured to guide object 10 to imaging station 131 at each iteration. According to some exemplary embodiments, the robotic arm 110 is also configured to guide the object 10 to the imaging station 131 at the end of the polishing process for grading the object 10, and optionally generate a signature key for the object 10 based on image data obtained after the last polishing iteration.

[0094] Figure 2This is a simplified schematic diagram of an example imaging system for an automated polishing apparatus according to some example embodiments. Imaging system 130 may reside in imaging station 131. According to some example embodiments, imaging system 130 includes a microscope imaging system 257 for high-resolution imaging and a telecentric imaging system 256 for capturing 2D images of object 10 at a lower resolution than said microscope imaging system 257. The imagers of microscope imaging system 257 and telecentric imaging system 256 are shown as 251 and 255, respectively. The illumination sources of microscope imaging system 257 and telecentric imaging system 256 are shown as 245 and 241, respectively. In some example embodiments, the illumination source 241 for telecentric imaging system 256 is coaxial Kohler illumination. illumination).

[0095] In some example embodiments, the microscope imaging system 257 is configured to support a magnification range from 1X to 20X and typically has multiple lenses. In some example embodiments, the microscope imaging system 257 is an inverted microscope, wherein the object being observed is located above rather than below the microscope objective. In some example embodiments, the microscope imaging system 257 provides a higher spatial resolution than the telecentric imaging system 256. For example, the field of view corresponding to a single pixel size of the telecentric imaging system 256 can be 10-20 times (e.g., 16 times) larger than the field of view corresponding to a single pixel size of the microscope imaging system 257.

[0096] According to some example embodiments, the telecentric imaging system 256 is configured to generate a preliminary (e.g., coarse) 3D model of object 10 based on shadow modeling. According to some example embodiments, a robotic arm 110 is configured to rotate and move object 10 relative to the telecentric imaging system 256 to capture contour images of object 10 in different orientations. The contours can then be used to construct a 3D model. In some example embodiments, the coarse 3D model generated by the telecentric imaging system 256 is then refined based on selected images captured with the microscope imaging system 257.

[0097] According to some example embodiments, the outputs from imaging system 256 and microscope imaging system 257 are processed in processor 170. Processor 170 may be integrated into computing device 151 and / or may be dedicated electronic circuitry configured for image processing. According to some example embodiments, controller 150 manipulates the 3D positioning of object 10 relative to telecentric imaging system 256 and microscope imaging system 257. Optionally, processor 170 is also configured to process the output from microscope imaging system 257 to detect the geometry and morphology of facet 15. Optionally, processor 170 is configured to detect and segment artifacts on facet 15.

[0098] Modeling an object using an automated faceting apparatus

[0099] Figure 3 This is a simplified flowchart of an example method for generating a 3D model of an object for faceting, according to some example embodiments. Typically, the object is received along with faceting instructions (block 205). The instructions may include a 3D model of the object in its current configuration, such as a rough object before faceting and a 3D model of the target object. When a 3D model is available, the generated 3D model can be registered with a given 3D model so that the faceting instructions indicated in the given 3D model can be associated with the generated 3D model. Alternatively, the instructions may include the target polishing scale, desired cut and / or symmetry level as input, and the target object may be generated, for example, by an automated faceting device 100 at imaging station 131. For example, based on inspection at imaging station 131, the automated faceting device 100 may define a target object that provides the highest weight yield within a given scale. To translate the received instructions into instructions that can be executed by the automated faceting device 100, a 3D model of the object is generated using the automated faceting device 100. According to some example embodiments, an object is mounted on a robotic arm (block 210) before a 3D model is generated using the automated faceting device 100. Since the object is mounted on the robotic arm, 3D modeling is performed on the exposed parts of the object. For example, the object may first be mounted into a pavilion press-pot, where a specified crown is inside the press-pot and a specified pavilion is exposed.

[0100] According to some exemplary embodiments, a preliminary 3D model (block 215) of an object 10 positioned on a pressure vessel and a robotic arm is generated. Optionally, the preliminary 3D model is a rough model. In some example embodiments, shadow modeling is used to generate the preliminary 3D model. For shadow modeling, collimated backlighting, such as Kohler illumination, can be used to take multiple images from a known rotation angle, and the 3D model can be constructed based on back projections. Optionally, an imaging system other than a microscope imaging system, such as imaging system 256, can be used to construct the preliminary 3D model. According to some example embodiments, flat surfaces on the object are identified based on the preliminary model (block 220) and used to refine the 3D model (block 225).

[0101] In some example embodiments, the initial 3D model is refined by capturing images of a flat surface on the object using a microscope of the imaging system. The geometry of the flat surface can be determined and used to refine the initial 3D model to obtain a more accurate 3D model. According to some example embodiments, the 3D model is further refined during polishing as needed. According to some example embodiments, if a target model is available, registration is performed between the refined 3D model and the received target model (block 230). According to some example embodiments, the generated 3D model is updated during automatic faceting processing based on the object guided to the imaging station between polishing iterations (block 235).

[0102] According to some example embodiments, after polishing the exposed portions of an object based on the generated 3D model, the object can be mounted on a robotic arm in an alternative orientation to facet the portions of the object not exposed by the pressure vessel. With this arrangement, blocks 210-230 can be repeated to generate a 3D model of the portion of the object initially not exposed by the pressure vessel. For example, when faceting an object with a crown and a pavilion, the object can be first mounted with the designated pavilion exposed, shaped and polished, and then the designated crown exposed, with the polished pavilion positioned within the pressure vessel. According to some example embodiments, once one side (e.g., the pavilion) has been faceted and the other side (e.g., the crown) has been mounted, the 3D model of the first side can be registered with the 3D model obtained for the second part. Optionally and preferably, the partially exposed faceted portion of the object (the partially exposed pavilion) serves as a plane for registering the pavilion with the crown, on which a complete 3D model of the polished object can be obtained.

[0103] Generating a sequential list of facets

[0104] Figure 4A , 4B Figures 4C and 4C are simplified diagrams depicting three sets of example instructions for forming the same plurality of facets on an object, based on some example embodiments. The inventors have found that the polishing process can be further optimized based on the selection of the cutting order used for faceting. Optionally, the order can be selected to reduce the time spent faceting the object, improve the accuracy of the faceting, and / or the quality obtained. For example, Figures 4A-4C Three different sorting sequences are depicted for polishing facet 1, facet 2 and facet 3. Figure 4A The facet polishing sequence shown is facet 1, facet 2, facet 3. Based on Figure 4A The portion A removed to form facet 1 is significantly larger than the portions B and C that need to be removed to form facets 2 and 3 subsequently. Figure 4B The facet polishing sequence shown is facet 2, facet 1, facet 3. Based on this sequence, and... Figure 4A In contrast, the size of part B increases at the expense of the size of part A. Figure 4CThe facet polishing sequence shown is facet 3, facet 2, facet 1. According to this chosen sequence, the size of section C increases at the expense of section B. In this configuration, sections A, B, and C are similar in size. According to some example embodiments, one or more parameters may be considered when defining the facet order. Examples of parameters include, but are not limited to, polishing angle, amount of material to be removed, facet size, facet location, and artifacts on the object (e.g., internal and external). For example, polishing may be easier and faster at some polishing angles due to the crystal orientation of the object, while it may be more difficult and slower at others. In some example embodiments, the facet order is defined to reduce the time spent faceting the object. Alternatively and additionally, the facet order may be defined to increase the accuracy of faceting and / or the quality of the final product.

[0105] Figure 5 This is a simplified flowchart of an example method for generating a sequential list of facets for forming facets on an object whose chemical structure is a lattice, according to some example embodiments. According to some example embodiments, the volume of material to be removed during faceting is determined based on a 3D model of the object and a target model (block 230). According to some example embodiments, a preliminary processing is performed on the object before generating the sequential list to predict and / or determine its crystal axes. In some example embodiments, the projection of the crystal axes onto the facets is determined based on the preliminary processing (block 235). According to some example embodiments, a manufacturing fraction for each facet can be defined to achieve a desired result, such as rapid processing (block 240). The fraction can be based on known information, such as the volume of material to be removed around each facet, the orientation of the facet relative to the crystal axes, and artifacts detected in the object. A sequential list for forming facets can be generated based on the provided fractions (block 245). Faceting can be performed by an automated faceting device 100 based on the generated list (block 250). Optionally and preferably, the faceting process is monitored (block 255), for example. The imaging and sequential list between real-time monitoring and faceted iteration can be updated based on accumulated data from monitoring (block 260).

[0106] Automated detection of effective polishing directions

[0107] Figure 6This is a simplified flowchart of an example method for selecting the orientation of facets on a polishing wheel during polishing, according to some example embodiments. According to some exemplary embodiments, during polishing iterations, a robotic arm is used to position the surface of an object against the polishing wheel (block 305), and the robotic arm is configured to rotate the object about an axis perpendicular to the polishing wheel when the facets contact the polishing wheel (block 310). According to some example embodiments, one or more polishing-related parameters are sensed as the object is rotated (block 315). According to some exemplary embodiments, the direction for polishing can be selected based on the output from one or more polishing-related parameters (block 320), and the facets can be polished in the selected direction (block 325). In some example embodiments, a training or learning process can be applied, during which sensed signals during successful and unsuccessful polishing are recorded and used as a reference. Examples of polishing-related parameters may include acceleration, vibration sensed based on non-contact measurement, sound, heat, height displacement, current supplied to the motor or actuator of the robotic arm of the polishing wheel, and imaging.

[0108] In some example embodiments, an accelerometer is mounted on the pressure vessel to detect vibrations on the object. Optionally, when the object is oriented in a direction unfavorable to polishing, the object may bounce off the polishing wheel within a first frequency range, while when the object is oriented in a direction favorable to polishing, the vibration frequency may span a second frequency range. Optionally, the vibration amplitude may decrease when the object is oriented in a direction favorable to polishing. In another example, an increase in temperature on the polished surface may indicate a direction favorable to polishing. The inventors have found that significantly more heat is released during polishing by successfully breaking chemical bonds compared to the heat generated by friction without successfully breaking chemical bonds. Optionally, an infrared (IR) camera may be used, utilizing the infrared absorption of a laser (blackbody), to sense the temperature increase.

[0109] Figure 7A and 7B These are example diagrams based on some exemplary embodiments, illustrating the output of a sensor that senses polishing-related parameters as an object rotates about an axis perpendicular to the polishing wheel during polishing. In some example embodiments, a vibration sensor can sense vibration frequencies caused by contact between the object and the polishing wheel in different polishing directions, such as... Figure 7A As shown. Optionally, the frequency can be used to select the desired polishing direction. In some example embodiments, the desired polishing direction is the direction that provides polishing with improved material removal rate. In some exemplary embodiments, for example in Figure 7B The sounds depicted in the different polishing directions can be used to detect directions with relatively low polishing resistance and / or faster polishing rates. For example, the frequency and / or amplitude may change when the object is positioned in an orientation that facilitates polishing. For instance, when polishing is successful, certain sound frequency components may increase their amplitude due to material removal.

[0110] Figure 8A and 8B This is a simplified diagram illustrating an example crystal axis related to the facets of an object according to some example embodiments. When polishing materials with a crystalline chemical structure, such as diamonds by pressing a facet onto a polishing wheel, the orientation of the facet relative to the direction of rotation of the polishing wheel affects the ability to polish the facet. Due to the crystal structure, a facet may be easier to polish in the direction corresponding to the orthogonal projection of the crystal axis onto the facet, and less difficult to polish in other directions. Figure 8A An example object 10 with a crystalline structure and whose crystal axes are represented by vectors a, b, and c is depicted. The simple or effective polishing direction of each facet is the direction corresponding to the orthogonal projection of a, b, and / or c. For example, the projections on facet 15 are a1, b1, and c1, as shown below. Figure 8B As shown. Traditionally, manual trial-and-error techniques are used to detect a simple polishing direction for each facet. Different directions are tried first until a suitable direction is found, and then polishing is performed in that direction. This trial-and-error method can be time-consuming. In contrast, the inventors have discovered that the crystal axis of an object can be predicted based on detecting multiple candidate projections on one or more facets. Once the crystal axis is predicted, polishing directions can be selected for the other faces of the object without repeated trials. The inventors have also discovered that the crystal axis can be predicted based on detecting at least four candidate projections. Optionally, four candidate projections can be detected on a single facet or on 1-3 facets. Optionally, the prediction can be corrected or refined during the polishing of additional facets.

[0111] Figure 9This is a simplified flowchart of an example method for predicting the crystal axis of an object according to some example embodiments. According to some example embodiments, an initial trial-and-error process is employed to try multiple directions on the polishing facets, and the direction that is easier to polish is the one with the maximum removal rate within a given time interval. The trial-and-error process begins by placing one surface of the object against a polishing wheel (block 405) and rotating the object about an axis perpendicular to the polishing wheel (block 410). One or more polishing-related parameters are sensed in different object directions via surfaces on the polishing wheel (block 415). Representative examples of polishing-related parameters suitable for this embodiment include, but are not limited to, acceleration, vibration sensed based on non-contact measurement, sound, heat, height displacement, pressure, current supplied to the motor or actuator of the robotic arm of the polishing wheel, and imaging. In some example embodiments, the robotic arm is configured to rotate the object by 360° and / or + / - 180°, thereby allowing sensing in all directions. Other ranges, such as 180°, 270°, or 90°, may also be considered. Optionally, the object rotates in a continuous manner, such as by rotation. The angular velocity is 0.5-2 rad / s. In some example embodiments, the rotation can be performed in discrete steps, and one or more polishing parameters can be sensed in each discrete step.

[0112] In some embodiments, the removal rate is determined based on one or more sensed polishing-related parameters. The removal rate can be based on volume (e.g., μm). 3 The removal rate can be defined as per h or weight (e.g., mg / h). In some example embodiments, the removal rate can be determined based on parameters of dynamic detection, such as detecting the polishing direction based on sound frequency and displacement progress signals. Optionally, the volume is determined based on imaging the facet. Optionally, imaging is performed at an imaging station in a defined direction between trial polishing intervals. For example, the removed volume can be determined by 3D-to-2D matching or registration between the image of the current facet and a previously determined 3D model, as described above. The inspection can be repeated in multiple directions. Inspection can be utilized in addition to dynamic detection, and the removal rate can be determined based on imaging as well as dynamic detection. Optionally, imaging can be applied as a subsequent step to refine the detection of candidate polishing directions. According to some example embodiments, one or more candidate polishing directions (block 420) can be sensed for each facet for each test. Optionally, one primary and one or more secondary candidate polishing directions can be detected. The inventors have found that 1-4 candidate polishing directions can be detected for each facet. According to some example embodiments, when at least four candidate polishing directions are detected, prediction can be initiated (block 425, "Yes"), while when fewer than four candidate polishing directions are detected (block 425, "No"), one or more additional facets can be tested to detect candidate polishing directions until at least four directions are found (block 430).

[0113] Once at least four directions have been detected (block 425, "Yes"), the detected directions can be used to predict the crystal axes of the object (block 435). Optionally, additional facets can be tested to improve the prediction. The predicted crystal axes can be stored and used to select polishing directions to polish other facets of the object without performing a trial-and-error process on the facets (block 440). Each other facet can then be polished in the selected directions (block 445). According to some example embodiments, orthogonal projections of the predicted crystal axes can be calculated for each other facet, and polishing directions can be selected to correspond to one of the orthogonal projections. Optionally, the polishing direction selected for the facet can be the polishing direction corresponding to the largest orthogonal projection of the crystal axis on the facet. Other considerations, such as the morphology of the facet, may be applied in the selection. The inventors have found that the prediction method described herein reduces the time required to complete faceting and also avoids potential damage to the object.

[0114] According to some exemplary embodiments, the prediction treats the object as being formed of a single crystal and thus having a common set of crystal axes, and the easy and / or effective polishing directions are the orthogonal projections of the crystal axes onto the facets. In some embodiments of the invention, the crystal axes are inferred from easy and / or effective polishing directions determined during trial and error on 1-3 facets based on a 3D model of the object constructed as further detailed above. Optionally, each candidate polishing direction detected on a facet can be defined by a pair of Cartesian coordinates at any point on the facet. Each pair of Cartesian coordinates defines a vector of candidate polishing directions. According to some example embodiments, multiple possible directions of the crystal axes can be inferred based on the inferences performed. In some example embodiments, the prediction can be improved based on calculating the angular deviation between the estimated normal projection determined from the initial inference of the predicted crystal axes and the actual polishing direction determined based on the removal rate detected during the trial and error procedure. Optionally, the sum of the squared angular deviations associated with different polishing facets of the first set is calculated and used to refine the prediction. Optionally, if no convergence is detected, additional trial and error procedures can be initiated to obtain more data to improve the prediction.

[0115] Dynamic adjustment of polishing parameters

[0116] Figure 10This is a simplified flowchart of an exemplary method for adjusting polishing during operation using an automated polishing apparatus, according to some exemplary embodiments. According to some example embodiments, each facet may be polished over one or more polishing iterations. After a polishing iteration, the object can be inspected in an imaging station. The 3D model can be updated based on inspection and polishing instructions. Polishing iterations can be defined based on selected parameters sensed during polishing and / or based on estimated material removal. Optionally, the duration of each iteration is from 1 second to 1 minute, for example, a few seconds.

[0117] The polishing iteration begins with the object positioned against the polishing wheel (block 505). During polishing, one or more polishing-related parameters are detected, such as those monitored and used to monitor an estimated material removed during the process. Example polishing-related parameters include vibration, temperature, the height of the robotic arm along the Z-axis, the current supplied to the robotic arm to press the object against the polishing wheel, and the current supplied to the polishing wheel. According to some example embodiments, the iteration terminates based on one or more polishing-related parameters and / or the estimated material removed (block 515, "Yes"). Optionally, the average area of ​​the facets is estimated based on sensing and / or based on the estimated material removed and the modeled 3D geometry. Optionally, the iteration continues until a defined amount of material has been estimated to have been removed and / or a defined facet size or shape has been reached, as long as the temperature remains below a defined threshold and / or as long as a defined iteration duration has not been exceeded. At the end of the polishing iteration, the object is moved to an imaging station for inspection using the robotic arm (block 520).

[0118] According to some example embodiments, one or more polishing-related parameters sensed during iteration are also used to dynamically adjust polishing parameters (block 525). Optionally, adjustment includes adjusting one or more of the pressure applied by the robotic arm to press the object against the polishing wheel (block 530). Alternatively or additionally, adjustment includes adjusting the rotational speed of the polishing wheel (block 535). Alternatively or additionally, adjustment includes changing the polishing trajectory by moving the object along the diameter of the polishing wheel (block 540). Additional parameters that can be controlled in real time include polishing direction, polishing trajectory diameter, polishing trajectory roughness, and the duration of the polishing interval. Adjustments can be based on, for example, sensed temperature, polishing rate, vibration, static and dynamic friction, and device warpage. Parameters and their thresholds can be optionally and preferably selected to improve the smoothness and / or accuracy of polishing and reduce damage to the object during polishing.

[0119] When the stopping criterion for the iteration is related to the estimated amount of material removed, the amount of material removed can be estimated as the change in object height h, r, per unit time t (r = h / t) for a given facet surface area. The relationship between r, the pressure P exerted by the object on the polishing wheel, and the linear velocity of the polishing wheel is given by r = KPv, where K is the Preston coefficient. The Preston coefficient can be determined empirically for a particular device. An adaptation based on these is chosen to keep r generally constant. This can be done by selecting the force exerted by the object on the wheel based on a predetermined value of r, the rotational speed of the wheel, and the estimated area A of the facet being polished. According to some example embodiments, A is dynamically estimated based on the detected change in height h and the previously calculated facet area based on imaging. Specifically, the force F exerted by the object can be calculated as F = r / (KAv). The facet area can also be calculated between polishing iterations, for example, as the facet is imaged intermittently during polishing.

[0120] It is understood that the force exerted by the object depends linearly on the current used to control the robotic arm. Therefore, according to some embodiments of the invention, the current varies based on the value of area A to maintain a roughly constant value for r. This can be done without directly selecting the force. For example, a lookup table can be prepared in advance, which may include entries associating the current with the force and the area. In these embodiments, the method calculates the ratio r / (Kv) and then multiplies the ratio by A / A. LT Let's define query force, where A is the measured or estimated area of ​​the facet. LT This refers to the area entries in the lookup table. The method then searches the lookup table for a force value that matches the query force, extracts the corresponding current from the lookup table, and applies the extracted current to control the robot's force on the object. When no exact match is found, the method can use interpolation to extract an interpolated current.

[0121] The correlation between one or more polishing parameters and force (F) can be determined through a learning phase, which may involve generating reference information by measuring a large number of facets and recording frequencies and / or motor currents during polishing, while comparing this information with the actual material removal rate. According to some example embodiments, the operation of the robotic arm and / or polishing wheel can be adjusted to keep the material removal rate r substantially constant.

[0122] Iterative adaptation of polishing parameters

[0123] Figure 11This is a simplified flowchart of an example method for adjusting polishing based on image data captured using an automated polishing device, according to some example embodiments. According to some example embodiments, each facet may be formed in 1-20 polishing iterations. Between iterations, the object may be inspected, the 3D model of the object may be updated, and adjustments to the facet process may be defined based on the inspection. According to some example embodiments, the iteration cycle may include defined iterative polishing facets (block 605). Iterations may be defined based on duration, detected changes in height, and other polishing-related parameters as described herein. At the end of an iteration, the facets may be cleaned (block 610). Optionally and preferably, steam may be sprayed onto the facets for cleaning. According to some example embodiments, the object is guided to an imaging station and imaged (block 615). According to some example embodiments, the morphology of the facets is detected and / or characterized based on the imaging. Optionally, artifacts on the facet surface and / or internal artifacts may be detected based on the imaging. In some example embodiments, surface artifact segmentation and classification are performed. Optionally, bright-field and / or dark-field illumination may be used for segmentation and classification. Optionally, the polishing level is detected based on the imaging.

[0124] According to some example embodiments, the instructions for polishing an object can be adjusted based on imaging (block 617). When an uneven finished surface is detected, an exemplary adjustment may include increasing the polishing depth beyond the initial plan. Another example adjustment may include changing the polishing direction based on the detection of a crack. Yet another exemplary adjustment may be to continue polishing different facets and return to the current facet at a later stage, for example, by pushing the current facet to the end of the polishing sequence list.

[0125] According to some example embodiments, one or more polishing parameters are adjusted based on imaging (block 620). Exemplary adjustments may include reducing pressure on the object during polishing based on detected artifacts. Optionally, decompression may reduce the temperature of the object during polishing. Another example adjustment may include changing the polishing track based on detected scratches. Scratches may indicate that the polishing track is exhausted and needs replacement. An alternative track may be selected until the track is replaced. According to some example embodiments, the 3D model is adjusted based on polishing iterations to reflect the new structure of the object (block 625). Optionally, subsequent polishing iterations may be adjusted based on the updated 3D model.

[0126] Figure 12This is a simplified schematic diagram illustrating two example differences in the modeling geometry of an example facet according to some example embodiments and in the facet geometry that may occur during faceting. Facet 15 represents a facet modeled in the 3D model of object 10. The geometry of facet 15 is represented by the 3D model outline 25. In some example embodiments, the actual corresponding facet 15' may have been polished too deeply, such that the outline 25' of the actual corresponding facet 15' has a larger surface area than the 3D model outline 25. In some example embodiments, the actual corresponding facet 15" may have been polished, but with an angle (tilt) error, and the corresponding outline 25" of the actual corresponding facet 15" may be tilted relative to the 3D model outline 25. According to some example embodiments, these differences are corrected in the updated 3D model. In some example embodiments, these differences may also be a factor in modifying subsequent polishing instructions or even the ordering of the remaining facets.

[0127] Post-faceting inspection of an object

[0128] Figure 13 This is a simplified flowchart of an example method for detecting and recording object parameters at the end of the faceting process. According to some example embodiments, after the object is faceted and before it is unloaded from the robotic arm, the robotic arm guides the object to imaging station 131 for final inspection and characterization. According to some example embodiments, a 2D image of each facet of the object is captured using the microscope imaging system 257 in imaging system 130 (block 705). According to some example embodiments, grading parameters are determined based on the captured microscope images (block 710). Examples of grading parameters include cut grade, symmetry grade, and surface polishing grade. The grading can be stored on a computer-readable medium for reference (block 715).

[0129] In some example embodiments, the 2D image is also used to generate a signature key for the object. The signature key can be generated based on the characterization features of the facets in the image data. In some example embodiments, the geometry of each facet is determined based on the captured 2D image (block 720). In some example embodiments, the 3D position of each facet of the object is determined (block 725). The 3D position can be defined based on the coordinate system of the robotic arm 110 and / or based on a 3D model generated for the object. In some example embodiments, the morphology of one or more facets is characterized based on imaging (block 730). Optionally, detected artifacts can be segmented, classified, and / or characterized. According to some example embodiments, a signature key is generated based on the geometry, location, and morphology of the detected different facets (block 735). The signature key is stored on a computer-readable medium for reference (block 740). According to some example embodiments, blocks 705-740 can be performed once after faceting the pavilion of the object and repeated after faceting the crown of the object. Optionally, a grading can be defined after examining the crown and pavilion. Optionally, a signature key is generated after inspecting the crown and pavilion.

[0130] Dual-process faceting apparatus

[0131] Now for reference Figure 14A , Figure 14A A simplified schematic diagram of an exemplary automated faceting apparatus, including a laser cutting station and a polishing station, is shown. Figure 14B A simplified schematic diagram of a laser cutting station is shown, and Figure 15 A simplified flowchart of an example method for faceting an object by combining laser cutting and polishing is shown.

[0132] According to some exemplary embodiments, an automated device 700 configured for faceting an object 10 includes a laser cutting station 161 and a polishing station 121 for processing the object. In some example embodiments, laser cutting can significantly reduce the time spent faceting the object 10. In some example embodiments, the process is defined such that the first 70%-90% of the material is removed based on laser cutting at the laser cutting station 161, and the remaining material is removed based on polishing at the polishing station 121. Although polishing is generally a slower process, its advantage lies in that it typically provides higher precision and a better finish.

[0133] According to some example embodiments, the process begins by mounting object 10 onto robotic arm 110 (block 805) and configuring robotic arm 110 in imaging station 131 (block 810). In imaging station 131, a 3D model of the object is calculated based on the coordinate system of device 700, and, when available, the model is registered with a target model (block 815). A set of instructions for faceting object 10 can be defined. These instructions may include defining a first portion of the object to be removed with laser cutter 165 and a second portion of the object 10 to be removed with polishing wheel 120. In some example embodiments, the first portion is defined as removing 70%-90% of the material to form each facet, such that 10%-30% of the remaining material can be removed by polishing. In this way, polishing can be applied to complete each facet with the desired precision and polish finish.

[0134] According to some embodiments, during multiple first facet iterations, the robotic arm switches between placing the object 10 in the laser cutting station 161 for cutting with the laser beam of the laser cutter 165 and placing the object 10 in the imaging station for inspection (block 820). Optionally, one or more of the laser cutting parameters and / or the 3D model are updated based on the inspection in the imaging station 131 during the laser cutting iteration. Optionally, a switch is initiated only once per facet or facets. In some example embodiments, no switch is required during laser cutting and the inspection is performed at the end of the laser cutting process. In some exemplary embodiments, the laser cutter 165 is stationary and the robotic arm 110 is configured to orient the object 10 relative to the laser cutter 165. Optionally, the laser cutter may be configured to move in one or more directions, and the object 10 remains stationary in the laser cutting station 161.

[0135] When laser cutting is complete, for example when the first portion has been removed (block 825), robotic arm 110 begins iterating between holding the object in place at polishing station 121 and imaging station 131 (block 830). One or more polishing parameters and / or the 3D model may also be updated during polishing iterations based on inspection. Once polishing is complete (block 835), the object can be removed from robotic arm 110 (block 840). In some exemplary embodiments, the object is remounted on robotic arm 110, and different portions of the object are exposed, for example, a designated crown is exposed after the pavilion facets, and blocks 805-840 are repeated to facet other portions of the object.

[0136] Canister identification code

[0137] Figure 16This is an example pressure vessel for holding an object, according to some example embodiments. According to some example embodiments, an identification code 65 configured to identify the object may be provided on the pressure vessel 60 holding the object. According to some example embodiments, the pressure vessel 60 is formed with a plurality of blind holes 62 configured to receive plugs 63. Optionally, a pattern of inserted and uninserted blind holes 62 defines the identification code. In some example embodiments, the imaging system 130 is configured to identify the identification code based on imaging. Other methods for adding identification codes are considered. For example, a barcode may be attached to the pressure vessel 60. Optionally, a radio frequency identification (RFID) tag may be attached to the pressure vessel 60, and the identification code may be read using a dedicated reader.

[0138] Figure 17 This is a simplified flowchart of an example method for identifying objects using pressure vessel identification codes according to some example embodiments. According to some exemplary embodiments, the pressure vessel is marked with an identification code for identifying the object (block 905), and the object with the pressure vessel is mounted on a robotic arm (block 910). According to some example embodiments, the identification code is read in an imaging station (block 915), and instructions for faceted objects are obtained based on the read (block 920). Optionally, the operator can receive multiple faceted objects at any time. Optionally, each object can be mounted on the pressure vessel and marked with an identification code. Multiple objects can be processed at once, and the use of identification codes avoids confusion between objects.

[0139] In the devices and / or methods disclosed herein, several selected tasks may be accomplished by hardware, software or firmware, or by using a combination of them with an operating system.

[0140] For example, hardware for performing a selected task according to an embodiment of the invention can be implemented as a chip or circuit. As software, the selected task according to an embodiment of the invention can be implemented as a plurality of software instructions executed by a computer using any suitable operating system. In exemplary embodiments of the invention, one or more tasks according to exemplary embodiments of the methods and / or systems described herein are performed by a data processor, such as a computing platform for executing a plurality of instructions. Optionally, the data processor includes volatile memory for storing instructions and / or data and / or non-volatile memory for storing instructions and / or data, such as a magnetic hard disk and / or removable media. Optionally, network connectivity is also provided. A display and / or a user input device such as a keyboard or mouse are also optionally provided.

[0141] It should be understood that, for clarity, certain features of the invention described in the context of a single embodiment may also be provided in combination in a single embodiment. Conversely, for brevity, various features of the invention described in the context of a single embodiment may also be provided individually or in any suitable sub-combination or in embodiments suitable for any other description of the invention. Certain features described in the context of various embodiments should not be considered as essential features of those embodiments unless the embodiments are invalid without these elements.

[0142] example

[0143] The following example method is now used to predict crystal axes based on at least four empirically detected suitable polishing orientations on a diamond. This example, together with the above description, illustrates some embodiments of the invention in a non-limiting manner.

[0144] The method takes as input at least four suitable polishing directions empirically detected on 1-3 facets of an object with a crystalline chemical structure (e.g., diamond). The method outputs the directions of the crystal axis vectors a, b, and c (in the same Cartesian coordinate system) and the predicted polishing direction for each facet.

[0145] The method described below is for cases where the suitable polishing direction is an orthogonal projection of the a, b, or c crystal axes on the crystal facet and the object is in single-crystal form.

[0146] The method assumes the initial orientation of the crystal is unknown and uses all input orientations relative to the crystal's current orientation. Given a known 3D model, the geometric relationships between the input facets are known, allowing the inference of the original crystal axes, whose projections lead to our inputs. Here, Cartesian coordinates are used to describe the orientations of vectors a, b, and c, e.g., a = a x X+a y Y+a z wait.

[0147] Using the predicted crystal axis, the method can calculate the appropriate polishing direction (e.g., for each potential facet of a polyhedron that has not undergone a trial-and-error process) Figure 8B (As shown). For example, three suitable polishing directions (a1, b1, c1) are defined on the face perpendicular to vector n as: a1 = [n × [a × n]], b1 = [n × [b × n]], c1 = [n × [c × n]]. The symbol × represents the cross product. The calculation of the vector product in the Cartesian coordinate system is defined by formula (1):

[0148] [A × B] = (A y B z - A z B y)X + (A z B x - A x B z )Y + (A x B y - A y B x Z (1)

[0149] The input parameters of the method can be multiple coordinates for each facet (e.g., 5-20, or 10 coordinates). These are the Cartesian coordinates of three arbitrary points (e.g., the coordinates of three vertices, R1 = {X...}). 11 ,X 12 ,X 13}, R2={X 21 ,X 22 ,X 23},R3={X 31 ,X 32 ,X 33}) and the easy-polishing direction (the angle between the easy-polishing directions) and the R2-R1 direction). Input data in any other format can be used as needed.

[0150] The output parameters of the method are preferably the directions of vectors a, b, and c (e.g., in the same Cartesian coordinate system) and the predicted polishing direction for each face.

[0151] While the invention has been described in conjunction with specific embodiments thereof, it will be apparent to those skilled in the art that many alternatives, modifications, and variations will be readily apparent. Therefore, it is intended to include all alternatives, modifications, and variations falling within the scope of the appended claims.

[0152] The applicant intends that all publications, patents, and patent applications mentioned in this specification are incorporated herein by reference in their entirety, to the same extent as if each individual publication, patent, or patent application were specifically and individually identified and incorporated herein by reference. Furthermore, any references cited or indicated should not be construed as an admission that such references are prior art to the present invention. The headings in this application are used herein to facilitate understanding and should not be construed as necessary limitations. In addition, any priority documents of this application are incorporated herein by reference in their entirety.

Claims

1. A device for automatically faceting objects, characterized in that: The device includes: A polishing wheel; A robotic arm configured to position an object in contact with the polishing wheel; A sensor configured to sense polishing-related parameters during the polishing of the object by the polishing wheel; An imaging system; and A controller, configured as follows: Operate the robotic arm to rotate the object about an axis perpendicular to the polishing wheel; Sensing signals from the sensor are received in different directions on the object during polishing; as well as Based on the sensing signal, a polishing direction is selected from the different directions; The controller is further configured to operate the robotic arm to manipulate the object to a focal plane of the imaging system, and to operate the imaging system to image a facet of the object intermittently during the polishing process; and to automatically operate the robotic arm based on image data from the imaging system to change the polishing direction.

2. The device as described in claim 1, characterized in that: The controller is configured to rotate the object while maintaining contact between the object and the polishing wheel, and to continuously receive the sensing signals during the rotation.

3. The device as described in claim 1, characterized in that: The polishing direction selected by the controller is a direction in which the polishing-related parameters have predetermined characteristics.

4. The device as described in any one of claims 1-3, characterized in that: The sensor is configured to sense the vibration amplitude or frequency associated with the contact between the object and the polishing wheel during polishing, wherein the selected polishing direction is the direction in which the vibration amplitude or frequency exhibits predetermined characteristics.

5. The device as described in any one of claims 1-3, characterized in that: The sensors are selected from the group consisting of microphones, displacement sensors, and accelerometers.

6. The device as described in any one of claims 1-3, characterized in that: The sensor is a temperature sensor configured to sense heat dissipation during polishing based on the contact between the object and the polishing wheel, wherein the selected polishing direction is the direction in which the temperature exhibits predetermined characteristics.

7. The device according to any one of claims 1-3, characterized in that: The device includes at least one additional sensor configured to sense additional polishing-related parameters during polishing, and wherein the controller is configured to select the polishing direction based on the sensing signals from the sensor and the additional sensing signals from the additional sensor.

8. The device as described in any one of claims 1-3, characterized in that: The controller is configured to repeat the operation, the receiving, and the selection for each of the multiple facets on the object.

9. A method for automatically faceting an object, characterized in that: The method includes: The positioned object comes into contact with a polishing wheel; The object is rotated about an axis perpendicular to the polishing wheel using a robotic arm; Sensing signals are received from a sensor at different directions of the object during polishing, wherein the sensor is configured to sense polishing-related parameters, and wherein the sensor is configured to sense vibration, sound, displacement, heat dissipation, or current supplied to the robotic arm during polishing while the object is in contact with the polishing wheel; and A polishing direction is selected from the different directions based on the sensing signal.

10. The method as described in claim 9, characterized in that: The method includes maintaining contact between the object and the polishing wheel while rotating the object, and receiving a series of the sensing signals during the rotation.

11. The method as described in claim 9, characterized in that: The selected polishing direction is the direction in which the polishing-related parameters have predetermined characteristics.

12. The method according to any one of claims 9-11, characterized in that: The method includes sensing at least one additional polishing-related parameter during polishing and selecting the polishing direction based on the polishing-related parameter and the at least one additional polishing-related parameter.

13. The method according to any one of claims 9-11, characterized in that: The positioning, rotation, receiving, and selection are repeated for each of the multiple facets on the object.

14. The method according to any one of claims 9-11, characterized in that: The polishing process intermittently images a facet of the object, wherein the imaging is performed while the object is mounted on the robotic arm.

15. The method as described in claim 14, characterized in that: The method includes changing the polishing direction based on image data from an imaging system.

16. A method for automatically faceting an object, characterized in that: The method includes: Polishing an object with a polishing wheel while: Sensing at least two polishing-related parameters, wherein one of the at least two polishing-related parameters is the vertical position of the object; and In a closed-loop control, in response to the values ​​of the at least two polishing-related parameters, at least one operating parameter is adjusted, the operating parameter being selected from: the rotational speed of the polishing wheel, the contact pressure of the object on the polishing wheel, and the trajectory position of the object on the rotating wheel.

17. The method as described in claim 16, characterized in that: Select the adjustment to control the material removal rate in order to remove material from the object.

18. The method as described in claim 16, characterized in that: The method includes terminating polishing when the value of the parameter is within a predetermined range.

19. A device for automatically faceting an object, characterized in that: The device includes: A polishing wheel; A robotic arm configured to position an object in contact with the polishing wheel; A sensor configured to sense at least two polishing-related parameters during polishing of the object by the polishing wheel, wherein one of the at least two polishing-related parameters is the vertical position of the object; and A controller configured to adjust at least one operating parameter in response to the values ​​of the at least two polishing-related parameters during the polishing process and in closed-loop control, the operating parameter being selected from: the current to the robotic arm, the rotational speed of the polishing wheel, and the trajectory used on the polishing wheel.

20. The device as claimed in claim 19, characterized in that... The at least one polishing-related parameter is selected from the group consisting of: vibration, sound, displacement, heat dissipation, pressure applied to the object, and contact with the object when polishing with the polishing wheel.

21. The device as described in any one of claims 19-20, characterized in that... The at least one polishing-related parameter is the current supplied to the robotic arm, which is related to the pressure of the object on the polishing wheel.

22. The device as described in any one of claims 19-20, characterized in that... :include: Obtain a computer-readable medium storing a lookup table with multiple entries, each entry including the value of the polishing-related parameters and at least one associated operating parameter. Search the lookup table for an entry corresponding to the polishing-related parameters sensed by the sensor; and Set the at least one operation parameter according to the corresponding value in the entry.

23. A method for automatically faceting an object, characterized in that... The method includes: During the polishing of a first facet of an object, a robotic arm is operated to rotate the object about an axis perpendicular to a polishing wheel; During the polishing process, polishing-related parameters are sensed; Identify one to four directions of the robotic arm, wherein the polishing-related parameters have predetermined characteristics, thereby identifying one to four candidate directions for polishing. Repeat the operation, the sensing, and the identification for one or more additional facets of the object until at least four candidate orientations for polishing are identified; and The at least four candidate directions are used to select the polishing direction for the additional facets of the object.

24. The method as described in claim 23, characterized in that: The method includes predicting the crystal axis of the object based on the at least four candidate orientations.

25. The method as described in claim 24, characterized in that: The method includes defining an orthogonal projection of at least one crystal axis onto the additional facet of the object based on the prediction.

26. The method as described in claim 24, characterized in that: The method includes updating the prediction of the crystal axis based on sensing the polishing-related parameters while polishing at least one facet of the object in addition to the one or more additional facets.

27. The method according to any one of claims 23-26, characterized in that: The method includes imaging at least one facet of an object between polishing intervals, and updating the prediction of the crystal axis based on image data from the imaging.

28. A device for automatically faceting an object, characterized in that: The device includes: A laser cutting device, configured to cut objects; A polishing wheel, configured to polish the object; A robotic arm configured to grip the object; A controller is configured to operate the robotic arm to position the object relative to the laser cutting device to remove a first portion of the object by laser cutting, and subsequently operate the robotic arm to position the object relative to the polishing wheel for removing a second portion of the object by polishing without removing the object from the robotic arm, wherein the first and second portions are selected to reduce the duration required to polish the object; A processor; and An imaging system configured to capture images of the object mounted on the robotic arm. The controller is configured to operate the robotic arm to position the object relative to the imaging system, and The processor is configured to construct a three-dimensional model of the object held on the robotic arm based on the image, and to define the boundaries of the first and second portions based on the three-dimensional model.

29. The device as claimed in claim 28, characterized in that: The amount of material included in the first part is greater than the amount included in the second part.

30. A method for automatically faceting an object, characterized in that: The method includes: Operate a robotic arm on which an object is mounted to position the object relative to a laser cutting device for removing a first portion of the object by laser cutting; and Then, without removing the object from the robotic arm, the robotic arm is operated to position the object relative to a polishing wheel for removing a second portion of the object by polishing, wherein the volume of the first portion is larger than the volume of the second portion; The method further includes: The robotic arm is operated to position an object relative to an imaging system configured to define a three-dimensional model of the object and, based on the three-dimensional model, define the boundaries of the first and second portions, wherein the definition is performed prior to the laser cutting and the polishing; and The object is held on the robotic arm after the imaging and during the polishing and laser cutting processes.

31. A device for automatically faceting an object, characterized in that: The device includes: A polishing wheel; A pressure vessel marked with an identification code, configured to carry an object, wherein the identification code identifies the object; A robotic arm is configured to hold the pressure vessel and position the object in contact with the polishing wheel during polishing; An imaging system configured to capture images of the object on the robotic arm and define a three-dimensional model of the object based on the images; An identification code reader, integrated with the imaging system and configured to read the identification code when the robotic arm grips the pressure vessel; and A controller configured to acquire instructions on a computer-readable medium for polishing the object based on identifying the identification code on the pressure vessel, and configured to control the operation of the device based on the instructions to polish the object.

32. The device as described in claim 31, characterized in that: The pressure vessel includes: A snap-on component is configured to hold an object; A base portion configured to be mounted on a robotic arm for holding the pressure vessel holding the object; An intermediate portion extending from the base portion to the snap-fit ​​portion, wherein the intermediate portion includes a plurality of holes formed thereon; and Multiple plugs are configured to be selectively fitted into one or more of the multiple holes, wherein the selective fitting of the plugs defines the identification code.

33. A method for automatically faceting an object, characterized in that: The method includes: An object is mounted on a pressure vessel, wherein the pressure vessel includes an identification code configured to identify the object; Operate a robotic arm to position a pressure vessel carrying the object toward a reader configured to read the identification code; Based on the identification code, instructions for polishing an object on a computer-readable medium are obtained; and During the polishing process, the robotic arm and polishing wheel are operated according to the instructions to polish the object; The reader is integrated into an imaging system configured to capture images of the object on the robotic arm and to define a three-dimensional model of the object based on the images.

34. A method for defining a gemstone signature key for polishing gemstones, characterized in that: The method includes: An imaging system using an automated polishing device determines the geometry, three-dimensional position, and shape of each of the multiple facets of a gemstone; Based on the geometry, the three-dimensional position, and the morphology, a signature key for the gemstone is generated; and The key is stored on a computer-readable medium.

35. A method for faceting an object, characterized in that: The method includes: Obtain the 3D model of the object and the 3D shape of the target with multiple facets; For each of the multiple facets of the target shape, the amount of material to be removed from the object is calculated based on the model to form the facet; A sequential list of the multiple facets is generated by decreasing the computational complexity of the list; and A protocol for polishing multiple facets of the object is executed according to the sequential list.

36. A method for faceting an object, characterized in that: The method includes: Obtain a 3D model of the object, and define the target 3D shape with multiple facets; For each of the multiple facets of the target shape, the projection of the crystal axis of the object onto the facet is calculated based on the model; A sequential list of the multiple facets is generated by decreasing the calculated projection amounts within the list; and A protocol for polishing the plurality of facets is executed according to the sequential list.

37. A method for faceting an object, characterized in that: The method includes: Obtain a 3D model of the object, and define the target 3D shape with multiple facets; For each of the multiple facets of the target shape, the projection of the crystal axis of the object onto the facet, the amount of material to be removed from the object to form the facet, and a manufacturing fraction are calculated based on the model, the manufacturing fraction being a weighted combination of the projection and the amount. The ordered list of the plurality of facets is generated by decreasing the calculated score within the ordered list; and The protocol for forming the plurality of facets is executed according to the sequential list.

38. The method as described in claim 37, characterized in that: The method includes: Using an automated polishing device, at least two facets of the object are shaped; During the forming process, polishing-related parameters are sensed; and Based on the sensing, the crystal axis of the object is predicted; The sequential list for generating the plurality of facets is also based on the prediction.

39. The method as described in claim 38, characterized in that: The method includes: intermittently imaging the object as it is being formed to determine the geometry and morphology of the face being formed, and updating the sequential list based on the imaging.

40. The method according to any one of claims 38-39, characterized in that: The method includes: using the shaping to intermittently image the object to detect its shape; and updating instructions for polishing subsequent polishing iterations based on the detected shape.

41. The method as described in claim 40, characterized in that: The detection morphology includes the segmentation and classification of artifacts on a face or surface.

42. The method as described in claim 40, characterized in that: The update command is selected from the following groups: increase polishing depth beyond the initial plan, change polishing direction, change polishing pressure, change polishing wheel speed, change linear motion on the wheel, change polishing interval, and change the trajectory of the polishing wheel used for polishing and proceed to polishing different surfaces before completing the current polishing.

Images