Clamping method

Abstract

One aspect of the invention relates to a method for clamping a component of mechanical equipment, the clamping operation being performed by an operator using a clamping tool. The method includes, in particular, the steps of: Determining (130) a position and orientation of a digital model of the mechanical equipment in the augmented reality environment; Determining (140) a position and orientation of the clamping tool in the virtual reality environment; Calculating (150) a distance between the clamping tool and the component to be clamped; and Assisting (160) the operator during the clamping operation. The assistance is provided via the display of the augmented reality environment on the computer screen visible to the operator and is dependent on the calculated distance (150) between the clamping tool and the component to be clamped. Figure to be published with the abbreviation: Figure 1

Description

Title of the invention: Clamping method TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of tightening operations carried out by an operator in the context of production and maintenance activities of mechanical equipment, in particular mechanical equipment of an aircraft.

[0002] The present invention relates to a method of clamping one or more elements to be clamped of a mechanical equipment. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] Mechanical equipment, for example, the mechanical equipment of an aircraft, sometimes requires lengthy and complex operations carried out as part of production and maintenance activities. These operations are performed by one or more operators. Therefore, the operator must follow precise instructions and rules to ensure that the mechanical equipment is in perfect working order after the intervention. For example, during a tightening operation, the operator must use the correct tightening tool for each component to be tightened. Furthermore, the operator must apply a tightening torque within a defined tolerance range to each component, for example, a screw. Finally, when the tightening operation involves several components, there is sometimes a specific order to follow for tightening the different components (for example, for cross-tightening).Therefore, in order to guarantee the quality of a tightening operation, it is necessary to tighten the correct component, with the correct tightening tool, at the right time and to the correct tightening torque.

[0004] In order to assist the operator during his operations on mechanical equipment, various solutions, called intelligent workstation solutions, exist.

[0005] A category of intelligent workstation solutions, such as that offered by Arkite, uses a camera perpendicular to the work surface to observe the operations performed by the operator. These solutions are, for example, capable of guiding the operator step by step during the operation. However, recognizing the components to be clamped requires positioning the parts to be assembled very precisely and repeatably on the work surface. These solutions are therefore applicable to small mechanical equipment that can be assembled on a work surface such as a table. Furthermore, the identification of the components to be clamped and the clamping tools can only be performed in two dimensions (2D), parallel to the work surface. Thus, these systems cannot provide guidance for assemblies in three dimensions (3D) on complex and / or large equipment.

[0006] Another category of intelligent workstation solutions, such as that offered by Inbolt, specializes in 3D tool localization, particularly for clamping operations. These solutions consist of an instrumented housing mounted on the clamping tool. The housing contains 3D vision sensors and inertial sensors. These solutions use the data from the housing to locate the tool relative to the equipment. They also use a digital model of the mechanical equipment—that is, a 3D digital model that accurately represents the mechanical equipment geometrically—to feed a 3D shape recognition algorithm to locate the housing relative to the equipment.However, to enable the clamping tool to be located relative to the equipment, the housing must be positioned so that there are no obstructions between it and the mechanical equipment. Furthermore, the clamping tool's movements must be stable, slow, and controlled to maintain accurate positioning information relative to the mechanical equipment. Therefore, this solution is implemented in clamping operations that can be automated with robotic arms but is not suitable for use by a human operator.

[0007] A final category of smart workstation solutions, such as that offered by Diota, uses augmented reality to assist in the assembly or inspection of mechanical equipment. These solutions use a 2D camera to film the work area. From the video stream obtained with the 2D camera, an algorithm, known as a "model-based augmented reality algorithm," can locate a digital model of the equipment in the augmented reality environment by determining the position and orientation of the mechanical equipment relative to the 2D camera. To determine the position and orientation of the mechanical equipment relative to the 2D camera, the model-based augmented reality algorithm analyzes the video stream to determine the position and orientation of areas and / or edges of the mechanical equipment for each frame of the video stream.Some solutions in this third category attempt to locate mechanical equipment and tools within the same augmented reality environment, for example, to assist operators during tightening operations. However, in real-world situations, the tightening tool being used is barely visible to the 2D camera during the operation, making it difficult or even impossible to use augmented reality to locate it. Therefore, the loss of location information for the tightening tool by solutions in this third category prevents effective operator assistance during tightening operations.

[0008] Finally, there are solutions for locating elements in industrial environments adapted for equipping tools with trackers in order to locate them in workshops, for example. These solutions use technologies capable of detecting These solutions allow for the tracking of components over long distances so they can be located in workshops or on industrial sites. However, their accuracy is only on the order of tens of centimeters. They do not achieve the precision required to guide tightening operations, which is on the order of tens of millimeters.

[0009] There is therefore a need to provide a method for clamping an element to be clamped of a mechanical equipment which resolves at least in part the disadvantages of currently known solutions. Summary of the invention

[0010] The invention provides a solution to the problems mentioned above by enabling assistance to an operator during a tightening operation, performed using a tightening tool, of a component to be tightened on a piece of mechanical equipment. This assistance is provided by using a distance between the tightening tool and the component to be tightened. This distance is calculated in the method according to the invention by combining augmented reality and virtual reality techniques. The use of virtual reality to determine the position of the tightening tool makes it possible, in particular, to ensure continuous visibility of the tightening tool in the virtual reality environment. Thus, the position and orientation of the tightening tool can be reliably determined at any time during the tightening operation.Finally, the use of augmented reality to assist the operator is particularly suited to maintenance and production operations of mechanical equipment since the operator can easily view the screen displaying assistance information in the augmented reality environment during the tightening operation.

[0011] One aspect of the invention relates to a method for clamping a component of mechanical equipment, the clamping operation being carried out by an operator using a clamping tool in a work area, the method comprising the steps of: • Obtaining a digital model of the mechanical equipment, • Obtaining an augmented reality environment, displayed on a computer screen visible to the operator during the tightening operation, and a virtual reality environment, • Determining the position and orientation of the digital model in the augmented reality environment, the determination of the position and orientation of the digital model in the augmented reality environment being carried out: • by filming the mechanical equipment in the work area during the tightening operation using a 2D camera, and • by spatially superimposing the work area and the augmented reality environment, the spatial superposition of the work area and the augmented reality environment being implemented with a model-based augmented reality algorithm using footage of the mechanical equipment in the work area, • Determining the position and orientation of the clamping tool within the virtual reality environment, and • Calculation of the distance between the clamping tool and the element to be clamped, the calculation of the distance including sub-steps of: • Calculation of the position of the element to be clamped in the augmented reality environment based on the determined position and orientation of the digital model, • Achieving a common digital environment by spatially overlaying the augmented reality environment and the virtual reality environment, • Calculate the position of the clamping tool and the element to be clamped in the common digital environment, and • Operator assistance during the tightening operation, the assistance being: • performed via the display of the augmented reality environment on the computer screen visible to the operator, • carried out via the control of the clamping tool, and • dependent on the calculated distance between the clamping tool and the element to be clamped.

[0012] Thanks to the invention, the risk of errors related to human error during a tightening operation is reduced. Furthermore, the time required for a tightening operation is also reduced. Finally, the method according to the invention improves traceability to guarantee the quality of tightening operations performed on mechanical equipment.

[0013] In addition to the characteristics mentioned in the preceding paragraph, the method according to one aspect of the invention may have one or more additional characteristics from among the following, considered individually or in all technically possible combinations: • an error in calculating the distance between the clamping tool and the element to be clamped is less than 10 or 20 millimeters during the entire clamping operation, • a display, within the augmented reality environment, of information indicating the location of the component to be tightened on the mechanical equipment, • The clamping tool is computer-configurable; a clamping tool configuration includes a setting of a target tightening torque applicable by the clamping tool. • The operator assistance (160) includes setting the target tightening torque of the clamping tool based on the calculated distance (150) between the clamping tool and the element to be clamped, • A predetermined tightening torque value is applied to the element to be tightened. • The clamping tool is adapted to send to the computer a clamping torque induced by the clamping tool during the clamping operation, and • Operator assistance includes: • Determining the end of a tightening operation on the element to be tightened by determining that the tightening torque induced by the tightening tool during the tightening operation is within a predetermined tightening torque tolerance range, and • displaying information, within the augmented reality environment, indicating that the tightening operation of the element to be tightened is complete and whether this tightening is compliant or not, • The tightening operation consists of tightening an additional component of the mechanical equipment according to a tightening sequence that is at least partially predetermined, and • Operator assistance includes displaying information within the augmented reality environment indicating the next element to be tightened among the elements to be tightened, respecting the tightening sequence. • Mechanical equipment is equipment of an aircraft, including: • an aircraft engine, • a landing gear, • an engine nacelle, • a transmission box, and • cabin equipment of an aircraft.

[0014] Another aspect of the invention relates to a clamping system comprising: • A computer configured to implement the process according to the invention, • A screen connected to the computer and adapted to display the augmented reality environment, • A clamping tool: • computer configurable, a clamping tool configuration including a setting of a target tightening torque applicable by the clamping tool, • Adapted to send the tightening torque induced by the tightening tool during the tightening operation to the computer. • An augmented reality device including a 2D camera adapted to film a work area containing the mechanical equipment and the element to be clamped during the clamping operation, • A virtual reality device including at least one tracker suitable for locating the clamping tool and one tracker suitable for locating the camera.

[0015] The invention and its various applications will be better understood upon reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0016] The figures are presented for illustrative purposes only and are in no way limiting of the invention. • Fig. 1 shows a synoptic diagram illustrating the steps of an example of the method for assisting a clamping operation of a component to be clamped of a mechanical equipment according to the invention. • Figure 2 shows a schematic representation of an example of a clamping system for mechanical equipment according to the invention. • Fig. 3 is a synoptic diagram illustrating the sub-steps of an example of the step of calculating a distance between the clamping tool and the element to be clamped according to the invention. • Figure 4 is a synoptic diagram illustrating the sub-steps of an example of the operator assistance stage according to the invention. DETAILED DESCRIPTION

[0017] Unless otherwise specified, the same element appearing on different figures has a unique reference.

[0018] Fig. 1 is a synoptic diagram illustrating the steps of an example of the process 100 according to the invention.

[0019] Method 100 is a method for tightening one or more elements to a specific torque, having a threaded section, such as a screw, a grease fitting, or a screw-on plug. For simplicity, in the following description, we will detail an example of Method 100 with a single element to be tightened. However, Method 100 can, of course, be applied to several elements to be tightened. The element to be tightened using Method 100 is tightened onto a mechanical device by an operator. To perform the tightening operation, the operator uses a tightening tool. During the tightening operation, the operator is assisted, and the steps of Method 100 are carried out while the operator tightens the element. In one example, the mechanical device is an aircraft component. For example, the mechanical device is one of the following:

[0020] an aircraft engine,

[0021] a landing gear,

[0022] an engine nacelle,

[0023] a transmission box, and

[0024] aircraft cabin equipment such as seats.

[0025] The method 100 can be implemented by computer. By "implemented by computer," it is understood that all, or virtually all, of the steps of the method 100 are executed by at least one computer or processor or other similar system, such as a smartphone, tablet, or virtual or augmented reality headset. Thus, steps are performed by the computer, possibly fully automatically or semi-automatically. In some examples, the triggering of at least some of the steps of these methods can be achieved through user-computer interaction. The level of user interaction required may depend on the level of automation expected and weighed against the need to implement the user's wishes. In some examples, this level may be user-defined and / or predefined.User interaction can be performed using any device. When the computer includes a touchscreen or camera, user interaction can be performed with any part of the user's body, such as their hand or one or more fingers. The computer includes a screen adapted to display the augmented reality environment. This screen is visible to the operator during at least part of the clamping operation.

[0026] A typical example of a computer implementation of process 100 consists of executing process 100 with a system adapted for this purpose. The system may include a processor coupled to memory and a graphical user interface (GUI), the memory having stored a computer program containing instructions for implementing the process. The memory may also store a database. Memory is any hardware adapted for such storage, possibly comprising several distinct physical parts. In particular, the memory may store a digital model of the mechanical equipment. The digital model of the mechanical equipment faithfully reproduces the outer casing of the mechanical equipment. The term "faithfully" here means that the digital model reproduces the outer casing of the mechanical equipment identically, with an error of less than 1, 5, or 10 millimeters.The digital model can also include all or part of the components to be clamped on the mechanical equipment. The memory can also contain a digital model of the clamping tool. This digital model of the clamping tool can then be optionally displayed in the augmented reality environment. The memory can also... The memory can contain all the rules to be followed for the tightening operation. For example, the memory can store, for each component to be tightened, the minimum tightening torque to be applied, as well as the maximum tightening torque. It's worth noting that these minimum and maximum tightening torques can be different for each component during the tightening operation. The memory can also contain a tightening sequence to be followed. This stored tightening sequence can be complete within a strict order. A strict order dictates, in a predetermined manner, the position of each component within the tightening order. The stored tightening sequence can also be partial, within a sequence ordered according to a business rule.A sequence ordered according to a business rule determines which elements are authorized to be tightened during the tightening operation, based on the business rules specific to the current operation, for example, cross tightening. Alternatively, the stored tightening order can be free, within the framework of a free sequence. A free sequence does not impose any tightening order. Finally, the memory can contain the tightening tool(s), such as one or more wrenches or screwdrivers, suitable for tightening each element.

[0027] An example of a system adapted to implement process 100 is illustrated in [Fig. 2]. More specifically, [Fig. 2] illustrates a possible implementation, at an operator's workstation or in their work area, of such a system during the implementation of process 100. In [Fig. 2], the type 250 arrows with a solid line represent a superposition relationship, the type 260 arrows with regular dashes represent a location relationship, and the type 270 arrow with irregular dashes represents a distance relationship. The superposition relationship associates two elements that are superimposed, i.e., having the same position and orientation, in their respective environments, using, for example, augmented reality algorithms or calibration of the transformation matrix enabling the transition between the two elements.For example, the type 250 arrow between the virtual reality tracker 212 and the 2D camera 202 means that the tracker 212 is superimposed, in the virtual reality digital environment 211, on the 2D camera 202 (which is in the work area). A location relationship links two elements that allow the calculation of the relative position and orientation between the two elements in the corresponding digital environment. For example, the type 260 arrow between the mechanical equipment 204 and the 2D camera 202 means that the mechanical equipment 204 is located relative to the 2D camera 202; that is, its position and orientation relative to the 2D camera 202 are determined within the work area. The distance relationship designates the gap between two physical elements that the method 100 allows to be calculated in order to assist the operations. clamping. For example, the arrow of type 270 between the clamping element 205 and the connected clamping tool 206 means that the actual distance between the clamping element 205 and the connected clamping tool 206 is determined in the virtual reality digital environment 211.

[0028] The system, as illustrated in [Fig. 2], also includes at least one clamping tool. Each clamping element among the set of clamping elements may be compatible with one or more clamping tools. Thus, the operator may need to use several clamping tools during a clamping operation. The clamping tools may be connected. When connected, the clamping tool can be configured remotely by the computer implementing the process 100. The clamping tool configuration may, for example, include setting a target clamping torque that the clamping tool can apply. In other words, the computer can remotely configure the target clamping torque that the connected clamping tool can apply during a clamping operation. The target clamping torque is within a tolerance range, which defines the minimum and maximum clamping torques.The connected clamping tool can also send information about its use to the computer implementing process 100, such as the clamping torque applied or induced by the clamping tool during the clamping operation.

[0029] The system, as illustrated in [Fig. 2], further comprises an augmented reality device. The augmented reality device includes at least one 2D camera, labeled 202 in [Fig. 2]. The 2D camera 202 is adapted to film a work area containing the mechanical equipment 204 and the clamping element 205 throughout the clamping operation. The position and orientation of the clamping element 205 relative to the mechanical equipment 204 are predetermined. The digital model 203 of the mechanical equipment 204 may include a digital representation of the clamping element 205. The position and orientation of the digital equipment, relative to the 2D camera 202, can be determined using a model-based synchronization algorithm.It can be noted that the mechanical equipment 204 can thus be moved during the tightening operation and that, as a result, the position and orientation of the digital model 203 will be updated in real time in the augmented reality digital environment 210. Elements 202 to 205 are included in the augmented reality digital environment 210.

[0030] The system, as illustrated in [Fig. 2], finally includes a virtual reality device. The virtual reality device includes at least two trackers 209 and 212. The first tracker 209 allows the clamping tool 206 to be located in the virtual reality digital environment 211. The second tracker 212 allows the 2D camera 202 to be located in the virtual reality digital environment 211. Thus, this tracker 212 can be used to synchronize the Digital environments 210 and 211, i.e., determining the position and orientation of all elements of the augmented reality digital environment 210 within the virtual reality digital environment 211. In this example, the position and orientation of the 2D camera 202 can correspond to a first reference frame, the reference frame of the augmented reality digital environment 210. Thus, thanks to the tracker 212, it is possible to determine the transformation matrix that allows us to go from this first reference frame to a second reference frame, the reference frame of the virtual reality environment 211. This transformation matrix is ​​determined from the position and orientation of the tracker 212 in the second reference frame.Determining the position and orientation of trackers 209 and 212 in the virtual reality environment can be done using one or more beacons 207. Preferably, four beacons 207 can be used and arranged horizontally at the four corners of the work area 201 to form a rectangle. The beacons 207 can, for example, be placed at a height between 2 and 2.5 meters. These beacons 207 can also be placed, as illustrated in [Fig. 2], outside the physical area 208 managed by the virtual reality digital environment 211. In the example shown in [Fig. 2], the operator 214 has their back to the 2D camera 202. Thus, the operator 214 can see the screen 213, on which a real-time rendering of the augmented reality environment 210 is displayed, while performing the clamping operation. Furthermore, in this configuration, the operator can see themselves on the computer screen performing the clamping operation.

[0031] A step 110 of the process 100 includes obtaining, for example by computer, the digital model of the mechanical equipment. The term "obtain" in this application may mean "generate" using the computer, "receive" by the computer, or "access" by the computer (when the digital model is already stored in the computer's memory).

[0032] A step 120 of the process 100 includes, for example by means of a computer, obtaining an augmented reality environment. An augmented reality environment is a technology that overlays information and virtual objects onto the real world, generally through the use of devices such as screens, smartphones, tablets, smart glasses, or augmented reality headsets. Augmented reality thus enriches the user experience by integrating interactive digital elements into their physical environment. In the example of [Fig. 2], the augmented reality environment is displayed on a computer screen 213. The screen 213 is visible to the operator 214 during the tightening operation. The operator's assistance can therefore include the display of information and virtual objects in the augmented reality environment that are easily visible to the operator throughout the tightening operation.

[0033] Step 120 of process 100 also includes obtaining, for example by computer, a virtual reality environment. A virtual reality environment is an immersive computer simulation that recreates a realistic or fictional environment. It should be noted that in process 100, the virtual reality environment does not need to be displayed. Indeed, the virtual reality environment is used, in particular, to locate the clamping tool using, for example, a virtual reality tracker placed on the clamping tool.

[0034] The augmented reality environment may include a first reference frame. The virtual reality environment may include a second reference frame. Furthermore, a transformation matrix enabling the conversion from the second frame to the first frame may be known. For example, the transformation matrix can be calculated using a virtual reality tracker placed on the 2D camera of the augmented reality environment device. Thus, the position and orientation of the first reference frame, for example, the virtual reality tracker placed on the 2D camera, are determined in the second reference frame.

[0035] A step 130 of the process 100 comprises determining, for example by computer, the position and orientation of the digital model in the augmented reality environment. This determination is performed by superimposing the position and orientation of the mechanical equipment in the work area onto the position and orientation of the digital model in the augmented reality environment. This determination can be carried out continuously in real time throughout the clamping operation. Alternatively, it can be performed at a predetermined frequency, for example, 1, 5, or 10 hertz. Since the position and orientation of the digital model in the augmented reality environment are updated throughout the clamping operation, the mechanical equipment can be moved while remaining visible to the 2D camera 202 during the clamping operation.This step 230 can be implemented by filming, with the 2D camera, the work area including the mechanical equipment during the tightening operation. Then, using a model-based augmented reality algorithm, the work area and the augmented reality environment are spatially superimposed. Thus, the position and orientation of the digital model in the augmented reality environment are synchronized with the position and orientation of the mechanical equipment in the work area.

[0036] A step 140 of the process 100 includes determining, by computer for example, the position and orientation of the clamping tool in the environment virtual reality. To determine the position and orientation of the clamping tool, a virtual reality tracker can be placed on the tool. The update frequency of the virtual reality tracker's position and orientation, and therefore of the clamping tool, depends on the characteristics of the virtual reality device used. For example, the frequency can range from 10 to 300 hertz. It should be noted that this step 140 may include calculating the position, and even optionally the orientation, of a part of interest of the clamping tool based on the position and orientation of the virtual reality tracker. The part of interest is, for example, the part in contact with the element to be clamped.The calculation of the position of the part of interest can be performed using a first predetermined vector defining the position, relative to the virtual reality tracker, of the part of interest in the second reference frame. When the orientation of the part of interest is also calculated, it is possible to use a transformation matrix defining the position and orientation, relative to the virtual reality tracker, of the part of interest in the second reference frame.

[0037] A step 150 of the method 100 comprises calculating, for example by computer, a distance between the clamping tool and the element to be clamped. This step 150 comprises three substeps. Figure 3 is a block diagram illustrating the steps of an example of step 150 according to the invention. The first substep 151 of step 150 consists of calculating a position of the element to be clamped in the augmented reality environment based on the position and orientation of the digital model determined in step 130. The calculation 151 of the position of the element to be clamped in the augmented reality environment can be performed using at least one second predetermined vector defining the position, relative to the digital model, of the element to be clamped in the first reference frame.

[0038] The second substep 152 consists of obtaining a common digital environment. The common digital environment is obtained by spatially superimposing the augmented reality environment and the virtual reality environment. The spatial superposition of the two environments can be performed by determining, in the second reference frame, the position and orientation of the first reference frame. The spatial superposition of the two environments can also be performed by determining, in a common frame, the position and orientation of the first and second reference frames. Substep 152 thus makes it possible to generate a common digital environment, i.e., one sharing the same reference frame for the augmented reality environment and the virtual reality environment.Thus, the various calculations of positions and orientations, as well as the distance between the clamping tool and the element to be clamped, can be carried out in this common digital environment.

[0039] The third substep 153 consists of calculating the position of the clamping tool and the clamping element in the common digital environment based on the position of the clamping element in the common environment, calculated in step 151. The calculation 153 of the clamping element's position in the common digital environment can be performed using a transformation matrix that allows conversion from the augmented reality environment to the common digital environment, i.e., from the first reference frame to the frame of the common digital environment. The calculation 153 of the clamping tool's position in the common digital environment can also be performed using a transformation matrix that allows conversion from the virtual reality environment to the common digital environment, i.e., from the second reference frame to the frame of the common digital environment.

[0040] Finally, since the position of the clamping tool and the position of the element to be clamped are known in the common digital environment, it is possible to calculate the distance between the clamping tool and the element to be clamped.

[0041] In an example consistent with the preceding examples, an error in the calculation, performed in step 150, of the distance between the clamping tool and the element to be clamped is less than or equal to 10 millimeters throughout the entire clamping operation. In other words, the calculated distance 150 corresponds to the actual distance between the clamping tool and the element to be clamped with an error less than or equal to 10 millimeters throughout the entire clamping operation. This level of precision makes it possible to differentiate the element being clamped from other elements to be clamped nearby, or the next element that the operator will clamp from other elements to be clamped nearby, on mechanical equipment of varying sizes, for example, ranging in size from a few centimeters to several meters. For example, the size of a fastening pitch cannot be less than 30 millimeters.

[0042] A step 160 of the process 100 includes operator assistance during the clamping operation. The assistance is dependent on the distance, calculated in step 150, between the clamping tool and the element to be clamped; i.e., the type of assistance and / or its presentation varies according to the distance between the clamping tool and the element to be clamped. This distance makes it possible, in particular, to determine the element to be clamped that is closest to the clamping tool and thus to provide appropriate assistance at any time during the clamping operation, depending on the task the operator is performing. Furthermore, the assistance can be provided in different ways. For example, the assistance can be provided via the display of the augmented reality environment on the screen visible to the operator and / or via the control of the clamping tool.The term "piloting" is to be understood, in this application, in the broad sense of assistance in the use and / or automatic configuration of. certain parameters of the clamping tool. Several control examples are given later in the request.

[0043] In an example consistent with the preceding examples, the display in the augmented reality environment includes information on the location of the component to be clamped on the mechanical equipment. For example, additional information and / or virtual objects concerning the location of the component to be clamped are displayed in the augmented reality environment.

[0044] In an example consistent with the preceding examples, when there are at least two elements to be clamped in the clamping operation, the display in the augmented reality environment assists the operator in following a clamping sequence that is at least partially predetermined. For example, the sequence could be a strictly ordered sequence or a sequence ordered according to a business rule. Thus, the display in the augmented reality environment includes information indicating the next element(s) to be clamped in accordance with the clamping sequence. For example, a number is displayed on each of the next elements to be clamped on the mechanical equipment. The number corresponds, for example, to the position of the element to be clamped in the clamping sequence. The number 1 thus corresponds to the next element to be clamped according to the clamping sequence.Furthermore, it is worth noting that the number can be displayed even if the clamping element is not visible on the screen, for example for a clamping element that is hidden, by the operator or mechanical equipment, from the point of view of the 2D camera.

[0045] In an example consistent with the preceding examples, when the target tightening torque setting applicable by the clamping tool is computer-configurable, the operator's assistance 160 can understand the target tightening torque setting of the clamping tool. This setting is determined based on the calculated distance 150 between the clamping tool and the workpiece. For example, when the clamping tool is more than 10 or 20 millimeters from a workpiece, the maximum tightening torque can be zero. In other words, when the distance between the clamping tool and a workpiece exceeds a predetermined distance, the clamping tool is deactivated, i.e., its tightening torque is zero.When the clamping tool is close to a component to be clamped, for example at a distance of less than 10 or 20 millimeters, the clamping torque of the clamping tool can be automatically set to the specific torque of the component closest to the clamping tool. When this component closest to the clamping tool is not the next component to be clamped according to the clamping sequence, or is not one of the components to be clamped allowed by the clamping sequence, the clamping tool can instead be deactivated.

[0046] In an example consistent with the preceding examples, when the clamping tool is adapted to send the computer a clamping torque induced by the clamping tool during the clamping operation, the operator assistance 160 can include determining the completion of a clamping operation for one clamping element among the set of clamping elements. Figure 4 is a block diagram illustrating the steps of an example of step 160 according to the invention. In order to determine that the clamping operation of a clamping element is complete in a substep 161, it is possible to use a target clamping torque value to be applied to said clamping element. This target clamping torque value can be predetermined.Thus, by comparing this target tightening torque value, or more precisely the minimum and maximum tightening torque values ​​defining the tolerance range around the target torque, and the tightening torque induced by the clamping tool during the tightening operation, it is possible to determine that the tightening operation of the component to be clamped has been successfully completed and is therefore finished. Once the tightening operation completion information has been determined, this information can be displayed, in substep 162, within the augmented reality environment.

Claims

1. Demands Method (100) for clamping a component of mechanical equipment, the clamping operation being performed by an operator using a clamping tool in a work area, the method comprising the steps of: - Obtaining (110) a digital model of the mechanical equipment, - Obtaining (120) an augmented reality environment, displayed on a computer screen visible to the operator during the tightening operation, and a virtual reality environment, - Determination (130) of a position and orientation of the digital model in the augmented reality environment, the determination of the position and orientation of the digital model in the augmented reality environment being carried out: • by filming the mechanical equipment in the work area during the tightening operation using a 2D camera, and • by spatially superimposing the work area and the augmented reality environment, the spatial superimposition of the work area and the augmented reality environment being carried out with a model-based augmented reality algorithm using the film of the mechanical equipment in the work area, - Determination (140) of a position and orientation of the clamping tool in the virtual reality environment, and - Calculation (150) of a distance between the clamping tool and the element to be clamped, the calculation (150) of the distance comprising sub-steps of: • Calculation (151) of the position of an element to be clamped in the augmented reality environment from the determined position and orientation (130) of the digital model, • Obtaining (152) a common digital environment by spatially superimposing the augmented reality environment and the virtual reality environment, • Calculating (153) the position of the clamping tool and the element to be clamped in the common digital environment, and - Assistance (160) to the operator during the clamping operation, the assistance being: • carried out via the display of the augmented reality environment on the computer screen visible to the operator, • carried out via the control of the clamping tool, and • dependent on the calculated distance (150) between the clamping tool and the element to be clamped.

2. A method according to claim 1 wherein an error in the calculation (150) of the distance between the clamping tool and the element to be clamped is less than 10 or 20 millimeters during the entire clamping operation.

3. A method according to any one of the preceding claims in which the operator assistance (160) comprises a display, in the augmented reality environment, of information on the location of the element to be clamped of the mechanical equipment.

4. A method according to any one of the preceding claims wherein: - The clamping tool is computer configurable, a clamping tool configuration including a setting of a target clamping torque applicable by the clamping tool, and - the operator assistance (160) includes the configuration of the target clamping torque of the clamping tool as a function of the calculated distance (150) between the clamping tool and the element to be clamped.

5. A method according to any one of the preceding claims, wherein: - A predetermined tightening torque value to be applied to the element to be tightened, - The clamping tool is adapted to send to the computer a clamping torque induced by the clamping tool during the clamping operation, and - The operator assistance (160) includes: • determination (161) of the end of a clamping operation of the element to be clamped by determining that the clamping torque induced by the clamping tool during the clamping operation is within a predetermined clamping torque tolerance range, and • display (162) of information, in the augmented reality environment, indicating that the clamping operation of the element to be clamped is complete and whether this clamping is compliant or not.

6. A method according to any one of the preceding claims wherein: - the clamping operation consists of clamping an additional clamping element of the mechanical equipment according to a clamping sequence at least partially predetermined, and - the operator assistance (160) includes the display, in the augmented reality environment, of information indicating the next element to be clamped among the elements to be clamped in compliance with the clamping sequence.

7. A method according to any one of the preceding claims wherein the mechanical equipment is equipment of an aircraft from among: - an aircraft engine, - a landing gear, - an engine nacelle, - a transmission, and - cabin equipment of an aircraft.

8. Clamping system comprising: - A computer configured to implement the method according to any one of the preceding claims, A screen connected to the computer and adapted to display the augmented reality environment; a clamping tool: • computer configurable, a clamping tool configuration including a setting of a target tightening torque applicable by the clamping tool, • Adapted to send the tightening torque induced by the tightening tool during the tightening operation to the computer. An augmented reality device comprising a 2D camera adapted to film a work area in which the mechanical equipment and the element to be clamped are included during the clamping operation, A virtual reality device comprising at least a tracker adapted to locate the clamping tool and a tracker adapted to locate the 2D camera.

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