Method and apparatus for industrial processing

Abstract

A method, comprising: laying (200) a metal sheet, machined using a manufacturing machine according to a machining plan, on a working surface of the manufacturing machine, the machined metal sheet comprising a set of machined workpieces pertaining to respective machining orders, it being possible for the machined workpieces of the set of machined workpieces to be picked up from the machined metal sheet (13) by an operator; and acquiring (202) a set of images of the machined metal sheet. In response to the operation of picking-up of at least one machined workpiece (16) of the set of machined workpieces (15, 16, 17, 19) performed by the operator, the method comprises: applying a pattern-recognition procedure to the acquired images of the set of acquired images of the machined metal sheet to identify, as result of the pattern-recognition procedure (202), at least one position of the at least one machined workpiece picked up by the operator from among the machined workpieces of the set of machined workpieces of the machined metal sheet; processing, on the basis of said machining plan of the manufacturing machine, a reconstructed image of the machined metal sheet, where machined workpieces of the set of machined workpieces are located in the reconstructed image; making a comparison (314) of the at least one position of the at least one machined workpiece picked up with the respective positions of machined workpieces of the reconstructed image of the machined metal sheet; on the basis of the comparison made, issuing a signal of identification of the at least one machined workpiece picked up by the operator; computing (316), according to the identification signal and of said image reconstructed on the basis of said machining plan, a sequence of positions of further workpieces to be picked up from among the remaining machined workpieces of the machined metal sheet so as to indicate to the operator at least one further workpiece to be picked up pertaining to a machining order that is the same as that to which the at least one workpiece picked up pertains; and displaying (204) information regarding the workpiece picked up and, according to the identification signal issued, also indications on the further workpiece to be picked up pertaining to a machining order that is the same as that to which the at least one workpiece picked up pertains.

Description

[0001] METHOD AND APPARATUS FOR INDUSTRIAL PROCESSING

[0002] ****

[0003] TEXT OF THE DESCRIPTION

[0004] Technical field

[0005] The present description relates to methods and apparatuses for industrial machining operations, in particular industrial machining processes carried out using machine tools, such as laser machine tools, or else industrial processes carried out using lasers, for example laser cutting.

[0006] One or more embodiments may be applied, for example, in contexts of monitoring of the industrial process, such as integration of a flow of information in a sequence of machining steps.

[0007] Technological background

[0008] An operator of a manufacturing machine (or machine tool), such as a laser-cutting machine, selects which machined workpieces to pick up on the basis of a visual comparison of each workpiece produced (for example, cut out of a metal sheet) with a drawing of a workpiece pertaining to a respective order.

[0009] This involves an individual search for each finished workpiece and its assignment to a correct product order. After completion of the machining process, the workpieces made of cut or stamped sheet metal are frequently sent onwards for further production steps to be carried out downstream.

[0010] Subsequent machining operations may be adversely affected by an incorrect arrangement of the workpieces picked up by the operator. In particular, if different workpieces with many shapes are cut, visual comparison becomes expensive in terms of time and is incrementally subject to errors on the part of the operator. For instance, workpieces with a wide range of shapes may cause problems during recognition of the workpieces themselves and subsequent sorting, for example for workpiececollecting units that are specific for each order.

[0011] The document EP 3 529 012 B1 describes a method for providing support to an operator in sorting workpieces laid out on a sorting table and produced by a flatbed machine tool, in particular a laser-cutting flatbed machine tool or a punching flatbed machine tool. According to a machining plan, the above method uses a locating system for determining the spatial position of the operator’s hand. This position may be determined, for example, by means of a unit for providing assistance to sorting that is worn by the operator in a position close to his hand and the position of which is detected by the locating system or by means of image-based location using one or more video cameras. The method comprises the following steps: providing a position data set that includes the positions of the workpieces produced according to the machining plan on the sorting table; via the locating system, detecting a position of the operator’s hand; comparing the position of the operator’s hand with the positions of the position data set; identifying at least one workpiece that matches the position of the operator’s hand; and issuing a sorting signal that comprises information on at least one workpiece that matches the position of the operator’s hand.

[0012] The document EP 3 529 001 A1 describes a method for providing support to an operator in the process of sorting workpieces laid out on a sorting table, said workpieces being produced, in particular, by a lasercutting flatbed machine tool or a punching flatbed machine following a machining plan, the method comprising providing a data set of machining images of the machining plan, based upon the disposition of at least one workpiece. The method according to the invention moreover regards acquisition of images of the sorting table, on which a plurality of workpieces are spatially laid out adjacent to one another, and generation of a first data set of sorting images and repeated acquisition of images of the sorting table, and generation of a second data set of sorting images, once at least one workpiece of the plurality of workpieces spatially laid out adjacent to one another has been removed from the sorting table. According to the invention, the method comprises comparison of the sorting-image data sets, with incorporation the machining-image data set, where a sorting signal is generated that contains information that comprises the type, position and / or shape of at least one workpiece that has been removed.

[0013] Document EP 3 529 178 A1 discusses a method for providing support to an operator in sorting workpieces laid out on a sorting table and produced by a flatbed machine tool, in particular a laser-cutting flatbed machine tool or a punching flatbed machine tool, according to a machining plan uses a locating system for determining the spatial position of the operator’s hand. The position can be determined, for example by means of a unit for providing assistance to sorting, which is worn by the operator close to his hand and the position of which is detected by the location system or by means of location based upon images captured using one or more video cameras. The method comprises the following steps: providing a position data set that includes the positions of the workpieces produced according to the machining plan on the sorting table; via the location system, detecting a position of the operator’s hand; comparing the position of the operator’s hand with the positions of the position data set; identifying at least one workpiece that matches the position of the operator’s hand; and issuing a sorting signal that comprises information on at least one workpiece that matches the position of the operator’s hand.

[0014] The document EP 3 559 765 A2 describes a method for identifying workpieces, wherein: a manufacturing machine produces a plurality of workpieces, and the workpieces produced are distributed, after being sorted, among a number of workpiece-collecting units; the workpieces produced are sent on to the workpiece-collecting units by means of an automation device; and provided on the workpiece-collecting units are identification elements, each of which carries directly and / or indirectly information regarding the workpieces on the workpiece-collecting units. The method is characterized in that: the identification elements, each of which carries directly and / or indirectly information regarding the workpieces on the workpiece-collecting units, and which are supplied by a supply device, are taken from the location of a supply device to a transfer zone in the working area of the automation device; and in that the automation device takes each identification element supplied from the transfer zone to the associated workpiece-collecting units. The invention enables simple and inexpensive identification of the workpieces.

[0015] The document EP 3 529 675 A2 discusses the use of a system of internal tracking for control of production. The internal-tracking system has available multiple transceivers installed in a fixed way for determining the position of a number of mobile units, the position being determined, in particular, by evaluating the time of propagation of electromagnetic (radio) signals. The internal-tracking system is used for assigning one of the mobile units to an operator in an industrial production plant where steel and / or sheet metal are / is machined to determine the position of the operator assigned to the mobile unit by locating the mobile unit assigned using the internal-tracking system and to integrate the internal-tracking system in a production-control system in the industrial production plant.

[0016] Notwithstanding the vast activity in this field, as witnessed, for example, by the various documents listed previously, further improved solutions are desirable.

[0017] Object and summary

[0018] An object of one or more embodiments is to contribute to providing such an improved solution.

[0019] According to one or more embodiments, the above object may be achieved by a method having the characteristics set forth in the ensuing claims.

[0020] One or more embodiments may regard a corresponding apparatus for industrial processes. A manufacturing machine for laser cutting or for punching may be an example of such an apparatus.

[0021] One or more embodiments may regard a corresponding computer program product, which can be loaded into the memory of at least one processing device or circuit (e.g., a computer) and comprises portions of software code for executing the steps of the method when the product is run on at least one processing circuit. As used in the present disclosure, reference to the aforesaid computer program product is understood as being equivalent to reference to a computer-readable medium containing instructions for controlling the processing device in order to co-ordinate implementation of the method according to one or more embodiments. Reference to “at least one computer” is intended to highlight the possibility of one or more embodiments being implemented in modular and / or distributed form.

[0022] The claims form an integral part of the technical teaching provided herein with reference to the embodiments.

[0023] As exemplified herein, a method comprises operations such as: laying a metal sheet, which has been machined using a manufacturing machine according to a machining plan, on a working surface of the manufacturing machine, the machined metal sheet comprising a set of machined workpieces corresponding to respective machining orders, it being possible for the machined workpieces of the set of machined workpieces to be picked up from the machined metal sheet by an operator; acquiring a set of images of the machined metal sheet; and in response to the operation of picking-up of at least one machined workpiece of the set of machined workpieces performed by the operator: applying a pattern-recognition procedure to the acquired images of the set of acquired images of the machined metal sheet; identifying at least one position of the at least one machined workpiece picked up by the operator from among the machined workpieces of the set of machined workpieces of the machined metal sheet as result of application of the pattern-recognition procedure; processing, on the basis of said machining plan of the manufacturing machine, a reconstructed image of the machined metal sheet in which machined workpieces of the set of machined workpieces are located in the reconstructed image; making a comparison of the at least one position of the at least one machined workpiece picked up with the respective positions of machined workpieces of the reconstructed image of the machined metal sheet; on the basis of the comparison made, issuing a signal of identification of the at least one machined workpiece picked up by the operator; computing, as a function of the identification signal and of said image reconstructed on the basis of said machining plan, a sequence of positions of further workpieces to be picked up from among the remaining machined workpieces of the machined metal sheet so as to indicate to the operator at least one further workpiece to be picked up pertaining to a machining order that is the same as that to which the at least one workpiece picked up pertains; and displaying information regarding the workpiece picked up and, as a function of the identification signal issued, an also indications on the further at least one workpiece to be picked up pertaining to a machining order that is the same as that to which the at least one workpiece picked up pertains.

[0024] One or more embodiments have the purpose of assisting an operator in the process of selection or sorting of workpieces, exploiting a design file from which to start in order to reconstruct a comparison image.

[0025] One or more embodiments provide a method and an apparatus that are more agile and more reliable in the event of any faults.

[0026] One or more embodiments facilitate the operations of storage of machined workpieces.

[0027] One or more embodiments enable the operator to be guided during the sequence of picking-up of machined workpieces, thus speeding up operations and increasing accuracy.

[0028] For instance, the method as exemplified herein comprises, in response to reception of a signal for end of picking-up of the set of machined workpieces by the operator, carrying out the operations of: making a comparison between the last acquired image of the set of acquired images and the reconstructed image of the machined metal sheet; and, on the basis of the comparison made, identifying machined workpieces of the set of the machined workpieces that have remained in the machined metal sheet, and issuing a report signal indicating the positions of, and the orders regarding, the workpieces of the machined workpieces of the machined metal sheet that have remained.

[0029] For instance, the method as exemplified herein comprises, in response to reception of a signal for end of picking-up of the set of machined workpieces by the operator or in response to issuing of the report signal, governing advance of the machined metal sheet laid on the working surface in the direction away from the body of the manufacturing machine so as to get what remains of the machined sheet to proceed towards a scrap heap.

[0030] As exemplified herein, a method comprises the operations of: applying a rectification-processing procedure, such as a perspective transformation, to the acquired images of the set of acquired images of the machined metal sheet, to obtain as result a set of rectified images; identifying, in the rectified images of the set of rectified images, a contour of the metal sheet; extracting, within the area defined by the contour of the metal sheet previously identified, the areas of interest of each machined workpiece; computing, on the basis of the extracted areas of interest of each machined workpiece, the coordinates of the workpieces within the above areas; and identifying, on the basis of the image-processing procedure applied to the rectified frames, the workpieces that have been picked up by the operator.

[0031] In the method as exemplified herein, for example, the machining plan of the manufacturing machine comprises a file in XML (extensible Markup Language) format that describes the design geometries of the workpieces of the machined metal sheet.

[0032] As exemplified herein, an apparatus (such as a manufacturing machine for industrial laser-machining processes, preferably laser-cutting processes or punching processes) comprises: at least one working surface configured for being coupled to a manufacturing machine and for conveying a metal sheet machined according to a machining plan out of the body of the manufacturing machine at the end of the machining operation, the machined metal sheet comprising a set of machined workpieces corresponding to respective machining orders, it being possible for the machined workpieces of the set of machined workpieces to be picked up by an operator from the machined metal sheet; at least one detection device coupled to the working surface and configured for acquiring a set of images of the machined sheet; and a processing device coupled to said at least one detection device and configured, in response to the operation of picking-up of at least one machined workpiece of the set of machined workpieces performed by the operator, for applying a processing procedure according to the method as described above.

[0033] For instance, the apparatus comprises at least one interface device coupled to the processing unit and configured for displaying information regarding the at least one workpiece picked up and, according to the identification signal issued, also indications on the further workpiece to be picked up pertaining to a machining order that is the same as that to which the at least one workpiece picked up pertains.

[0034] For instance, the interface device comprises a touchscreen of a video terminal configured for displaying messages for the operator and / or receiving commands from the operator.

[0035] Brief description of various views of the drawings One or more embodiments will now be described, purely by way of example, with reference to the annexed drawings, wherein:

[0036] Figure 1 is a diagram exemplifying an apparatus according to the present description;

[0037] Figure 2 is a diagram exemplifying a method according to the present description;

[0038] Figure 3 is a diagram exemplifying operations of the method according to the present description; and

[0039] Figure 4 is a diagram exemplifying the principles underlying one or more embodiments.

[0040] Detailed description of examples of embodiments

[0041] In the ensuing description, one or more specific details are illustrated in order to enable an in-depth understanding of examples of embodiments of the present disclosure. The embodiments may be obtained without one or more of the specific details or with other methods, components, materials, etc. In other cases, known operations, materials, or structures are not illustrated or described in detail so that certain aspects of the embodiments will not be obscured.

[0042] Reference to “an embodiment” or “one embodiment” in the framework of the present description is intended to indicate that a particular configuration, structure, or characteristic described with reference to the embodiment is comprised in at least one embodiment. Hence, phrases such as “in an embodiment” or “in one embodiment” that may be present in one or more points of the present description do not necessarily refer precisely to one and the same embodiment.

[0043] Moreover, particular conformations, structures, or characteristics may be combined in any adequate way in one or more embodiments.

[0044] The references used herein are provided merely for convenience and hence do not define the sphere of protection or the scope of the embodiments.

[0045] As used herein, the term “image” refers to a digital image, i.e. , to the numerical representation of a two-dimensional image, in particular a bitmap representation whereby the image comprises a matrix of dots, referred to as pixels, the coloring of which (in shades of grey or other colors) is encoded via one or more numerical values, referred to as bits.

[0046] For reasons of simplicity, in setting forth the concepts described herein reference is mainly made to production systems that machine flat sheet metal, such as the ones that use (laser) punching or laser cutting to produce workpieces for subsequent machining steps from so-called metal sheets or plates, of material having a pre-set thickness and pre-set dimensions, for instance. It remains on the other hand understood that the above type of manufacturing machines is purely provided by way of example and is in no way limiting. One or more embodiments may be applied virtually to any type of manufacturing machine or machine tool.

[0047] Figure 1 is a schematic illustration of an example of apparatus (or system) 10 configured for carrying out a method according to the present description.

[0048] As exemplified in Figure 1 , the above apparatus 10 comprises: a manufacturing machine 11 , for example a laser-cutting machine comprising a mobile structure that can be moved (for example, via actuators) according to the axes (e.g., the cartesian axes X, Y and Z) and comprising a laser head configured for guiding a laser beam from a laser source towards a rough metal sheet to carry out laser machining thereon, for example to carry out laser cutting of the rough metal sheet to produce a machined metal sheet 13; at least one working surface 12 coupled to the manufacturing machine 12 and configured for receiving therefrom the machined metal sheet 13; for example, the machined metal sheet 13 may be conveyed onto the working surface 12 via a mechanism of conveying rollers, in a way in itself known; optionally, the working surface 12 may be extended by providing a second working surface 12’ (which can be integrated in an extensible way in the working surface 12) with a short side adjacent to a corresponding short side of the working surface 12, in a way in itself known; at least one detection device 14, such as one or more video cameras provided with a pattern-recognition or vision system for recognition of the images, which is coupled to the manufacturing machine 11 and is configured for detecting and issuing signals (or data) regarding the metal sheet and / or one or more workpieces 15, 16, 17, 19 of the machined sheet 13 laid on the working surface 12; at least one interface unit 18, such as one or more displays, configured for displaying information on the metal sheet and / or one or more images of workpieces 26 of the machined sheet 13, for example for guiding the operator in the operation of picking up the workpieces 15, 16, 17, 19 in a sequence developed for enabling picking-up of a subset of workpieces 16, 17 that have in common the fact that they pertain to a specific order for the workpieces 15, 16, 17, 19 of the machined sheet 13; and a control unit 20, such as a processing unit or computer, which comprises or is connected to a data-storage memory 22, which is in turn coupled to the manufacturing machine 11 , to the at least one interface unit 18, and to the at least one detection device 14, the control unit 20 being configured for receiving from the detection device 14 signals (or data) regarding the metal sheet and / or one or more workpieces 16 of the machined sheet 13 and for supplying to the interface unit 18 information on the sheet 13 and / or one or more images 26 of workpieces of the sheet 13 on the basis of a sequence developed for enabling picking-up of workpieces pertaining to a specific product order, the sequence being developed on the basis of a comparison between signals regarding the process of the manufacturing machine 11 stored in the memory 22 and signals received from the at least one detection device 14.

[0049] As represented in Figure 1 , the interface unit 18 may comprise an input / output device, for example a touchscreen of a video terminal for an operator, with which an operator can, for example, display messages or enter commands.

[0050] As may be appreciated by the person skilled in the branch, the control unit 20 may be installed on the manufacturing machine 11 or may be located at a distance therefrom and connected to the various elements 11 , 14, 20 via wired or wireless communication means, in a way in itself known.

[0051] In addition or as an alternative, the control unit 20 may also correspond to a centralized unit for managing a coordinated set of manufacturing machines 11 so as to manage both data processing of the various detection devices 14 and programming of the operations of machining of the workpieces and the sequence of machining thereof by the manufacturing machines of the coordinated set of manufacturing machines.

[0052] For instance, the control unit 20 may be configured, in particular, for enabling real-time processing to facilitate picking up of the cut workpieces 15, 16, 17, 19 on the part of the operator.

[0053] As may be appreciated by the person skilled in the branch, the control unit 20 may comprise a CNC unit 22, as well as a servo-drive module or card, i.e., a card that comprises one or more servo drives (for example, of a DSP CPCI type for control of one or more actuators or motors), servo amplifiers, or servo control modules for the motors / actuators of the body of the manufacturing machine 11 , in a way in itself known. For instance, the CNC unit, according to procedures in themselves known in the prior art, generates / applies a sequence of programming instructions P that corresponds to a so-called part program, for a virtual machine with given specifications of acceleration and speed of movement of the head of the manufacturing machine. For instance, the control unit 20 may comprise an operating system of a Linux type associated to extensions of a real-time type for managing the manufacturing machine 11 and for processing the signals coming from the detection device 14. For instance, the control unit 20 likewise comprises a programmable logic controller (PLC) specialized in managing or controlling industrial processes.

[0054] As exemplified in Figure 1 , from a metal sheet there can be obtained various freely selectable shapes (for machines with flat working surface, a plane shape) via machining using the manufacturing machine, in particular using laser technology. The subsequent processes of bending and welding then generate a product.

[0055] In manufacturing machines 11 with flat working surface, in a way in itself known, a machining plan (e.g., a cutting plan) is stored as input parameter for control of the machine 11 , where the machining plan contains the shapes of the workpieces produced and the relative positions with respect to one another. In addition to the machining plan (e.g., the cutting plan), it is possible to use also additional information obtained during the machining procedure, such as a transformation of coordinates to adapt the machining (cutting) plan to the actual position of the sheet 13 being machined. This information is, for example, stored in the memory 22 of the control unit 20 coupled to the machining plan (e.g., the cutting or punching plan) of the manufacturing machine 11.

[0056] In laser-cutting or (laser-)punching flatbed manufacturing machines 11 , the presence of a precise cutting plan, in combination with an image of the surface on which the cut material produced is laid (i.e. , the workpieces 15, 16, 17, 19), can be used to assist the operator in carrying out an efficient sequence of selection of the workpieces and / or to obtain suitable information for further machining stages.

[0057] In addition or as an alternative, the detection device 14 can recognize the workpieces 15, 16, 17, 19 from among the ones that have remained on the working surface 12 without being picked up on account of machining problems, for example in order to generate a report that will then be useful for the control unit 20 to re-introduce the workpieces into the production cycle.

[0058] As exemplified in Figure 1 , an apparatus 10 may comprise a method aimed at recognition, via the detection device, of the shapes of the workpieces 15, 16, 17, 19 present on the metal sheet 13. For instance, the detection device 14 may be equipped with a pattern-recognition system via which it detects the workpieces that are picked up by the operator from the working surface 12. For instance, the detection device 14 supplies such information to the control unit 20, which, by comparing the image with a file stored in the database 22 may, for example, supply to the interface unit 18 the signals for showing the operator the characteristics and the relevant product order associated to the workpiece that has been picked up (e.g., the image 26 that reproduces the shape of the workpiece 16).

[0059] In the present description, by “pattern recognition” is meant automatic recognition of patterns and regular features in signals, in particular in signals supplied by the detection device 14. This recognition may be obtained with any modality in itself known, for example via neural networks, rule-based systems, classic fuzzy systems, Bayesian systems, fuzzy neural-network systems. It is possible to envisage a training step, in which a training data set is used for training the pattern-recognition model, prior to a patternrecognition step using the trained model, this step, which is implemented during machining, being referred to hereinafter also as inference step (in particular, with reference to the use of pattern recognition via neural networks).

[0060] For reasons of simplicity, one or more embodiments are discussed in what follows with reference to a case provided by way of example, in which the detection device 14 comprises a video camera equipped with pattern-recognition systems capable of identifying patterns in signals, such as audiovisual signals. The aforesaid case is provided purely by way of nonlimiting example. In one or more embodiments, the detection device 14, in addition or as an alternative to the video camera, may comprise virtually any device for detecting the shape of objects, for example a device based upon electromagnetic-wave remote-detection systems, where the electromagnetic waves are in frequency bands other than that of visible light, or sound-wave remote-detection systems.

[0061] As exemplified in Figure 2, a method of assistance to sorting of the workpieces 15, 16, 17, 19 of the machined metal sheet 13, comprises: block 200: laying the sheet or plate made of any material (e.g., metal) that has been machined (e.g., with profiles of different workpieces cut out of it) on the working surface 12 of the manufacturing machine 11 (e.g., a lasercutting machine); block 202: activating the video camera 14 for acquiring videos of the workpieces 15, 16, 17, 19 present in the machined metal sheet 13 laid on the working surface 12 and of their displacement by the operator (e.g., following upon picking-up of a first workpiece 16), then making a comparison between the image acquired and an image of the machined metal sheet or plate reconstructed starting from a design file (e.g., an image digitalized via the control unit 20), and, according to the comparison made, recognizing the workpieces that have been picked up by the operator (e.g., the first workpiece 16) as corresponding to one or more product orders stored in the memory 22 of the control unit 20; as indicated by the arrow, which has one end that starts from block 202 and the opposite end that points to the same block, the detection device 14 remains active as long as the operator is picking up workpieces from the metal sheet laid on the working surface 12, the processing procedure being repeated for each workpiece being picked up; block 204: via the display device 18 (e.g., a display panel), displaying a digital image of each workpiece of the machined metal sheet 13 that is being picked up by the operator and that has been recognized via the processing procedure performed in block 202 (e.g., the first workpiece 16); for example, on the display 18 there may be displayed a digital image of the workpiece that has been picked up (e.g., the workpiece 16) along with information on which other workpieces (e.g., the workpiece 17) of the machined metal sheet 13 form part of the same order as that of the workpiece that has been picked up so as to suggest to the operator a sequence of picking-up and arrangement of the machined workpieces (e.g., suggesting picking up a second workpiece 17 after the workpiece 16 has been picked up); block 206: once the operator terminates picking-up of the workpieces from the metal sheet present on the working surface 12, on the display 18 there may appear a request for confirmation of end of the operations of picking-up and arrangement of the workpieces 15, 16, 17, 19; this operation may comprise a check, by making a comparison between images acquired by the video camera 14 and a model stored in the memory 22 of the control unit 20, to verify whether there are no longer workpieces that can be picked up from the machined metal sheet 13, or else whether there remain workpieces that have been cut but not picked up (e.g., a workpiece 19 that has a low-quality cut edge); block 208: in the case where the operator confirms that he has finished and the image-processing procedure (for example, performed in the control unit 20) verifies that there are no longer workpieces that can be picked up from the machined metal sheet 13, the control unit 20 is configured for governing shifting of the working surface 12 (e.g., in the direction away from the body of the manufacturing machine 11 ) so as to get the remains of the machined metal sheet 13 to proceed towards a scrap heap and so as to free space to receive a new metal sheet that in the meantime has been processed in the body of the manufacturing machine 11 ; block 210: in the case where the operator confirms that he has finished and the image-processing procedure verifies that there are still workpieces that can be picked up from the metal sheetthat has remained on the surface 12 (for example, because they have machining defects so that it is not possible to remove them from the metal sheet ), the control unit 20 is configured to draw up a report (e.g., a digital document stored in the memory 22) that contains information regarding the workpieces that have remained and regarding to which orders these remaining workpieces belong (for example, the report indicates that the workpiece 19 has not been picked up and that it forms part of an order other than that of the workpieces 16, 17 that have been picked up); block 212: at the end of drawing of the report, the control unit 20 is configured for governing shifting of the working surface 12 (e.g., in the direction away from the body of the manufacturing machine 11 ) so as to get the remains of the machined metal sheet 13 and the workpieces that have not been picked up (e.g., the workpieces 15, 19) remaining therein to proceed towards a scrap heap and so as to free space to receive a new sheet or plate that in the meantime has been processed in the body of the manufacturing machine 11 .

[0062] In the case where the working surface 12 is extended via the addition of the second working surface 12’, blocks 208 and 212 may envisage asking the operator to select on which working surface the operation is completed before proceeding to relative displacement of the two working surfaces.

[0063] It should be noted that the possibility of having two working surfaces 12, 12’ has been mentioned to exemplify the possibility of having in general an extensible set of working surfaces, without any a priori constraints to the number thereof.

[0064] As exemplified in Figure 3, carrying out processing (e.g., digital processing via the control unit 20) to recognize the workpieces that have been picked up by the operator (e.g., the first workpiece 16) within one or more product orders stored in the memory 22 of the control unit 20 comprises: block 300: receiving a message of activation of the detection device 14, for example a message supplied by the control unit 20; block 301 : receiving from the control unit 20 a set of reference signals, for example encoded in an XML file, regarding the metal sheet or plate 13 being machined, to be used in subsequent operations for supplying a reconstructed image of the shapes and positions of the workpieces on the working surface 12; block 302: activating the video camera of the detection device 14, preferably with a dedicated thread 304 (e.g., a computer process that manages a subprogram run in parallel for speeding-up processing), for example for acquisition and processing of images; block 306: processing the images captured via the video camera of the detection device 14, to obtain as result of processing a correspondence between the images of the workpieces and the shapes and positions supplied to the machine tool; block 308: selecting a single image or frame from among the images captured over time by the video camera (or a video stream of the video camera) that will represent the image to be processed; optionally, it is possible to apply rectification processing to the images, such as a perspective transformation, so as to be able to compare the shapes of the workpieces cut out of the metal sheet with the models (for example, by applying a rotation to the image so as to be able to compare its shape with the shape that results from the coordinates used for machining the workpiece that has been cut out itself), thus providing a set of rectified frames; block 310: applying an image-processing procedure to the (optionally rectified) frame, the image-processing procedure comprising, for example, the operations of:

[0065] - identifying, within the frame, a contour of the sheet or plate 13;

[0066] - identifying a complete set of geometrical shapes present within the working area;

[0067] - extracting, within the area defined by the contour of the sheet or plate 13 previously identified, the areas of interest of each workpiece;

[0068] - selecting, from the area defined by the contour of the sheet or plate 13, only the geometries that respect the criteria of minimum and maximum surface area previously calculated in the XML file; and

[0069] - computing the coordinates of the positions of the areas within the contour of the sheet or plate 13 selected; block 312: identifying, on the basis of the image-processing procedure applied to the rectified frames, the workpieces that have been picked up by the operator (e.g., the workpiece 16), then comparing the frame (optionally rectified) with a graphic reconstruction of the file (e.g., in XML format or some other language based upon a syntactical mechanism that enables definition and control of the meaning of the elements contained in a document) that describes the design geometries of the workpieces on the machined sheet or plate; for example, the operation comprises identifying the shape of the contour cut out of the metal sheet 13 corresponding to the workpiece that has been picked up and, by matching it with the geometry and position of the elements contained in the XML file, uniquely identifying the workpiece that has been picked up (for example, by associating thereto a corresponding identifier code); block 314: iterating the operation of steps 306-312 for each frame until a set of workpieces that have been picked up by the operator is identified; and block 316: in response to identification of the set of workpieces picked up by the operator, computing a sequence on the basis of the comparison between the workpiece identified with the workpiece stored in the memory 22 of the control unit 20, such as the graphic reconstruction of the file that describes the geometries of the machined workpieces, and communicating the corresponding information to the display device 18.

[0070] For instance, block 316 comprises communicating the sequence containing information on which other workpieces (e.g., the workpiece 17) of the machined metal sheet 13 form part of the same order as that to which the workpiece that has been picked up pertains so as to suggest to the operator a sequence of picking-up and arrangement of the machined workpieces (for example, suggesting to the operator to pick up a second workpiece 17 after he has picked up the workpiece 16).

[0071] As exemplified in Figure 4, an operation of reconstruction of one or more images of workpieces obtained from the metal sheet 13 starting from an instruction file stored in the memory 22 of the control unit 20 may yield as result a reconstructed image 40 comprising images of various workpieces 25, 26, 27, 29 that, according to design, are expected to be found in the machined metal sheet 13.

[0072] In the case where, by comparing the reconstructed image 40 with the frame (optionally rectified) selected from among the images acquired by the detection device 14, it emerges that the workpieces actually machined have a different arrangement, for example on account of malfunctioning of the machine, the method may comprise drawing up a report, which can then be used for subsequent processing.

[0073] Without prejudice to the underlying principles of the invention, the details and embodiments may vary, even appreciably, with respect to what has been described herein purely by way of example, without thereby departing from the sphere of protection, as this is specified in the annexed claims.

Claims

CLAIMS1. A method, comprising: arranging (200) a sheet metal (13), machined with an operating machine (11 ) according to a machining plan, over a service flatbed (12) of the operating machine (11 ), the machined sheet metal (13) comprising a set of machined parts (15, 16, 17, 19) related to respective machining orders, the machined parts in the set of machined parts (15, 16, 17, 19) being removable from the machined sheet metal (13) by an operator; acquiring (202) a set of images of the machined sheet metal (13), and, in response to the removal by the operator of at least one machined part (16) in the set of machined parts (15, 16, 17, 19), applying a pattern recognition processing (300, 302, 304, 306, 308, 310, 312) to acquired images in the set of acquired images of the machined sheet metal (13), identifying (306) at least one position of the at least one machined part removed by the operator (16) in the set of machined parts (15, 16, 17, 19) as a result of the pattern recognition processing (202); processing, based on said machining plan of the operating machine (11 ), a reconstructed image (40) of the machined sheet metal (13), wherein machined parts in the set of machined parts (15, 16, 17, 19) are located in the reconstructed image (40); performing a comparison (314) of at least one position of the at least one removed machined part (16) with the respective positions of machined parts in the reconstructed image of the machined sheet metal (13); based on the comparison performed (314), issuing an identification signal (316) of the at least one machined part removed by the operator (16); computing (316), as a function of the identification signal and of said image reconstructed based on said machining plan, a sequence ofpositions of further parts to remove among the remaining machined parts (15, 17, 19) of the machined sheet metal (13), in order to indicate to the operator at least one further part (17) to remove related to a same machining order of the removed part (16), and displaying (204, 18) information (26) related to the removed part (16) and, as a function of the issued identification signal, indications related to the further part to remove (17) related to a same machining order of the removed part (16).

2. The method according to claim 1 , comprising: in response to receiving an ending signal of removal of the set of machined parts (15, 16, 17, 19) by the operator: performing a comparison (206) of the last image acquired in the set of acquired images with the reconstructed image of the machined sheet metal (13); based on the comparison performed, identifying (210) machined parts in the set of machined parts that are left in the machined sheet metal, and issuing a report signal (212) indicative of the position and of the orders related to left parts of the set of machined parts of the machined sheet metal (13).

3. The method according to any one of the previous claims, comprising: in response to receiving an ending signal of removal by the operator of the set of machined parts (15, 16, 17, 19) or in response to issuing the report signal (212), driving a sliding of the machined sheet metal arranged on the service flatbed (12) along a direction distancing from the body of the operating machine (11 ) so as to let the remaining of the machined sheet metal (13) proceed towards a pile of scraps.

4. The method according to claim 1 or claim 2, comprising: applying a rectification processing (308), such as for example a prospective transformation, to acquired images in the set of acquired images of the machined sheet metal (13), obtaining as a result a set of rectified images; identifying (310) in the rectified images of the set of rectified images, an outline of the sheet metal (13); extracting (310), inside of the area of the previously identified outline of the sheet metal, the areas of interest of each machined part; computing (310), based on the areas of interest extracted of each of machined parts, the coordinate of parts inside these areas, and identifying (312), based on image processing applied to rectified frames, the parts removed by the operator.

5. The method, according to any one of the previous claims, wherein said machining plan of the operating machine (11 ) comprises a file in an Extensible Markup Language, XML file format which comprises design geometries of the parts of the machined sheet metal (13).

6. An apparatus (10), comprising: at least one service flatbed (12) configured to be coupled to an operating machine (11 ) and configured to move a machined sheet metal (13) according to a machining plan outward of the body of the operating machine (11 ) at the end of the machining, the machined sheet metal (13) comprising a set of machined parts (15, 16, 17, 19) related to respective machining orders, the machined parts in the set of machine parts (15, 16, 17, 19) being removable from the machined sheet metal (13) by an operator, at least one sensing device (14) coupled to the service flatbed (12) and configured to acquire (202) a set of images of the machined sheet metal (13), anda processing device (20) coupled to said at least one sensing device (14) and configured to, in response to removal by an operator of at least one worked machined part (16) in the set of machined parts (15, 16, 17, 19): apply a pattern recognition processing (300, 302, 304, 306, 308, 310, 312) to the acquired images in the set of acquired images of the machined sheet metal (13), identifying (306) at least one position of the at least one machined part removed by the operator (16) n in the set of machined parts (15, 16, 17, 19) as a result of the pattern recognition processing (202); process, based on said machining plan of the operating machine (11 ), a reconstructed image (40) of the machined sheet metal (13) wherein machined parts in the set of machined parts (15, 16, 17, 19) are located in the reconstructed image; perform a comparison (314) of the at least one position of the at least one machined part (16) removed, with the respective positions of machined parts of the reconstructed image of the worked sheet metal (13); based on the performed comparison (314), issuing an identification signal (316) of the at least one work machined part removed by the operator (16), and compute (316), as a function of the identification signal and offset reconstructed image based on said machining plan, a sequence of positions of further parts to remove among the remaining machined parts (15, 17, 19) of the machined sheet metal, in order to indicate to the operator at least one further part (17) to remove related to a same machining order of the removed part (16), the apparatus (10) further comprising at least one interface device (18) coupled to the processing device (20) and configured to display information (26) related to the removed parts (16) and, as a function of the identification signal issued, indications related to the further part to remove (17) related to a same machining order of the removed part (16).

7. The apparatus (10) according to claim 6, wherein the processing device (20) is configured to, in response to receiving an ending signal of the removal of the set of machined parts (15, 16, 17, 19) by the operator: perform a comparison (206) between the last image acquired in the set of acquired images and the reconstructed image of the machined sheet metal (13); based on the comparison performed, identify (210) a machined part of the set of machined parts that are left in the machined sheet metal, and issue a report signal (212) indicative of the position and of the orders related to remaining parts of the machined parts of the machined sheet metal.

8. The apparatus (10) according to claim 6 or claim 7, wherein the processing device (20) is configured to, in response to receiving an ending signal of the removal of the set of machined parts (15, 16, 17, 19) by the operator or in response to issuing the report signal (212), drive a sliding of the machined sheet metal arranged on the service flatbed (12) along a direction of distancing from the body of the operating machine (11 ) so as to make the remaining of the machined sheet metal (13) proceed towards a pile of scraps.

9. The apparatus (10) according to anyone of claims 6 to 8, wherein: said at least one sensing device (14) comprises one or more videocameras, and said processing device (20) is configured to: apply a rectification processing (308), such as, for example, a perspective transformation, to the images acquired in the set of acquired images of the machined sheet metal (13),obtain as a result a set of rectified images; identify (310) in the rectified images of the set of identified images, an outline of the sheet metal (13); extract (310), within the area of the identified outline of the sheet metal (13) previously, the areas of interest of each machined part; compute (310), based on the areas of interest extracted from each machined part, the coordinates of the parts within these areas, and identify (212), based on the image processing applied to rectified frames, the parts that have been removed by the operator.

10. The apparatus (10) according to anyone of claims 6 to 9, wherein: the apparatus (10) comprises an operating machine (11 ) for industrial laser machining processes, preferably laser cutting or laser punching, and on the interface device (18) comprises a touchscreen display of a video terminal configured to display messages to the operator and / or to receive comments from the operator.

Images