Method for determining inspection poses of a part to be inspected and associated determination device

Abstract

Method for determining inspection poses for a part to be inspected and associated determination device. The present invention relates to a method for determining inspection poses for a part to be inspected, comprising the following steps: - provision (110) of a digital model of the part to be inspected; - determination (120) on an outer surface of the digital model of a plurality of patches, each patch having an area on said outer surface; - determination (130) of patches inaccessible by an inspection device among the set of patches determined; - filtering (140) of the set of patches to remove the inaccessible patches; - determination (160) of a path for a robotic arm to reach, by means of the inspection device, the inspection points of the filtered set of patches; - transformation (170) of the path and the inspection points into a plurality of inspection instructions for the robotic arm.Figure for the abbreviation: Figure 3.

Description

Title of the invention: Method for determining inspection poses of a part to be inspected and associated determination device

[0001] The present invention relates to a method for determining control poses of a part to be controlled.

[0002] The present invention also relates to a determination device associated with this determination method.

[0003] The invention relates more particularly to the field of inspection of a part, for example of a part of an aircraft or any other part whose inspection is of significant importance.

[0004] The inspection includes, in particular, the identification of defects in this part, for example, microcracks or fissures on the surface of such a part. Of course, the inspection may include the identification of other defects, for example, manufacturing defects or wear of such a part.

[0005] In the prior art, non-destructive testing techniques using dye penetrant testing are known for performing such an inspection. These techniques involve applying fluorescent products to the part to reveal its defects. However, these techniques require the use of polluting chemicals and present particularly difficult working conditions for the operator.

[0006] The infrared thermography technique is also known, which consists of locally heating each area of ​​the room to be inspected and then observing the heated area.

[0007] It is possible, for example, to heat the room by induction and then observe the circulation of eddy currents being disturbed by geometric defects such as cracks.

[0008] However, the implementation of such an inspection technique presents a number of disadvantages.

[0009] For example, the installation of a control device comprising either the heating device or the camera enabling observation of the local current distribution must be done in a particularly precise manner.

[0010] To achieve this, the use of a robot with a robotic arm is known, allowing it to assume different control poses around the part to be inspected. This arm carries the control device or the part and thus enables precise positioning.

[0011] However, the determination of poses for the robotic arm is generally carried out manually according to the know-how of the operator operating the robot.

[0012] This then presents a particularly laborious process and difficult to implement in a repeatable manner with the same quality.

[0013] The present invention aims to simplify the implementation of an inspection process for a part to be inspected. In particular, the invention makes this process more reliable and easier to implement, independent, for example, of the operator's expertise.

[0014] To this end, the invention relates to a method for determining control poses of a part to be inspected by a control device mounted on a robotic arm, comprising the following steps: - provision of a digital model of the part to be inspected; - determination on an external surface of the digital model of a plurality of patches, each patch presenting an area on said external surface associated with a control point from which this area is controllable by the control device; - determination of patches inaccessible by the control device among all the patches determined; - filtering of all patches to remove inaccessible patches; - determination of a trajectory for the robotic arm to reach, via the control device, the control points of the filtered set of patches; - transformation of the passage trajectory and control points into a plurality of control instructions for the robotic arm.

[0015] According to other advantageous techniques of the invention, the method comprises one or more of the following features, taken individually or in combination according to all technically feasible possibilities: - in which the digital model of the part to be inspected is a representation

[0016] CAD of this part; - in which the step of determining the plurality of patches includes the following sub-steps:

[0017] - segmentation of the outer surface of the part into a plurality of surfaces of work ;

[0018] - 2D projection of each work surface;

[0019] - determination of a plurality of patches on the 2D projection of each surface of work ;

[0020] - determination of the 3D position of each patch on the work surface corresponding; - the dimensions and shape of each patch are chosen according to a sensitive part of the control device. - the patches are determined on the outer surface with a predetermined overlap. - each control point is located at a predetermined distance from the outer surface of the part to be controlled. - The determination of inaccessible patches is carried out according to the dimensions and the movement mechanics of the robotic arm and / or the control device. - the determination of inaccessible patches is further carried out according to a minimum gap and a minimum angle of the control device with respect to the part of the outer surface associated with the corresponding patch. - the determination of inaccessible patches also includes a repositioning of patches following an accessibility test. - The determination of inaccessible patches includes the implementation of a 6D attraction technique of the control device to the corresponding control point. - the process further includes a step of ordering the patches from the filtered set of patches according to predetermined rules. - the passage trajectory is determined according to the ordering of the patches.

[0021] The invention also relates to a computer program comprising software instructions which, when executed by a computer, implement the process as defined above.

[0022] The invention also relates to a device for determining control poses of a part to be controlled by a control device mounted on a robotic arm, comprising technical means configured to implement the method as defined above.

[0023] The invention also relates to a control device comprising the determination device as defined above.

[0024] The invention will become clearer upon reading the following description, given solely by way of non-limiting example and with reference to the drawings in which: - [Fig.1] The [Fig.1] is a schematic view of a determination device according to the invention; - [Fig. 2] Fig. 2 is a schematic view of a control installation implementing an infrared thermography process, the process being implemented using the determination device of the [Fig.1]; - [Fig. 3] [Fig. 3] is a flowchart of a determination process according to the invention, the method being implemented by the main figure determination device; - [Fig. 4] [Fig. 5] [Fig. 6] [Fig. 7] [Fig. 8] [Fig. 9] [Fig. 10] Figures 4 to 10 are different views illustrating different stages of the determination process [Fig.3].

[0025] A determination device 10 according to the invention has indeed been represented on [Fig.1].

[0026] This determination device 10 makes it possible to determine control poses of a part to be inspected by a device mounted on a robotic arm.

[0027] This determination device 10 can, for example, be used to implement a part inspection process, carried out by a control installation 12, which is schematically illustrated in [Fig. 2]. In the example described, the inspection process corresponds to an infrared thermography process. However, in general, any other inspection process requiring at least one robotic arm for its implementation can be considered.

[0028] In particular, with reference to this [Fig.2], the control installation 12 comprises a first robotic arm 14, a second robotic arm 16 and a support 18.

[0029] Each of the robotic arms 14, 16 then has an arm that is articulated by a robot along, for example, three axes of rotation. The robot itself is, for example, movable in translation along, for example, three axes and possibly in rotation.

[0030] In the example of [Fig.2], the first robotic arm 14 includes a first control device 22 which in this example has an infrared camera.

[0031] The first control device 22 is, for example, mounted on the first robotic arm 14, which rotates about three axes. In some examples, this control device 22 is mounted rigidly with the first robotic arm 14, since the arm can itself be articulated relative to the robot.

[0032] The first control device 22 further comprises a sensitive part which, in the case of an infrared camera, has an optical assembly for capturing infrared images. The optical assembly may, for example, have a substantially rectangular aperture, thus enabling the capture of rectangular images.

[0033] Advantageously, the sensitive part forms a control axis X which presents, for example, a focal axis in the case of a camera.

[0034] In the example of [Fig.2], the second robotic arm 16 is adapted to support a part to be inspected 24. This part to be inspected 24 is, for example, mounted in a rotational manner along three axes on one end of the robotic arm 16. The part to be inspected 24 is, for example, an aircraft part, such as a turbine blade from its engine.

[0035] The support 18 is adapted to support a second control device 26. In the illustrated example, this second control device 26 has an inductor which is then capable of locally heating the part to be controlled 24 by induction. The second control device 26 also has a sensitive part which, in the case of an inductor, is formed by its heating head.

[0036] The sensitive part of the second control device 26 is also oriented along a control axis X which in the case of an inductor corresponds for example to the axis of direction of heating by the heating head.

[0037] To implement the thermography process, the part to be inspected 24 is first mounted on the second robotic arm 16.

[0038] Next, this robotic arm 16 is positioned so as to be in the line of sight of the second control device 26. Furthermore, the part to be controlled 24 is orientable in the different directions by the second robotic arm 16 so that it is possible to expose the different areas of its external surface to the second control device 26.

[0039] The first control device 22 mounted on the first robotic arm 14 is orientable so as to be able to observe the same areas as the second control device.

[0040] Thus, when the second control device 26, which in the example of [Fig.2] is an inductor, locally heats a predetermined area of ​​the outer surface of the part to be controlled 24, the first control device 22, which in the example of [Fig.2] is an infrared camera, can observe this same area and possibly take infrared images.

[0041] In this example, each of the robotic arms 14, 16 has a plurality of predetermined control poses allowing the first control device 22 and the part to be controlled 24 to be positioned respectively so as to optimize the implementation of the inspection process.

[0042] Of course, many other examples of the implementation of a thermography process and more generally of any other inspection process allowing the part to be inspected 24 to be inspected by at least one robotic arm 14, 16 are also possible.

[0043] The determination device 10 according to the invention then makes it possible to determine a plurality of control poses for at least one robotic arm 14, 16. Advantageously, this determination device 10 makes it possible to determine a plurality of control poses for each of the robotic arms 14, 16.

[0044] In some embodiments, the determination device 10 is integrated into the installation 14 and in particular into one of the control devices 22, 26.

[0045] With reference to [Fig.1], the determination device 10 comprises an input module 31, a processing module 32 and an output module 33.

[0046] According to various embodiment examples, each of these modules 31 to 33 is implemented for example by one or more software programs.

[0047] In such a case, the determination device 10 further includes at least one processor which enables the implementation of this software and a memory which enables its storage.

[0048] According to another embodiment, at least one of the modules 31 to 33 has at least partially a programmable logic circuit, for example of the FPGA type (from the English "Field Programmable Gate Array").

[0049] The input module 31 allows external data to be received in order to determine control poses, as will be explained in more detail later.

[0050] In particular, the input module 31 allows for the reception of a digital model 34 representing the part to be inspected 24. For example, such a digital model 34 may be in the form of a CAD (Computer-Aided Design) representation of this part. Thus, this digital model 34 may be provided by a digital file containing a CAD file.

[0051] The input module 31 is further connected to a database 35 which provides characteristics of the control device and of the robotic arm for which the control poses must be determined.

[0052] For example, these characteristics include the external dimensions of these elements, their capacity for rotational and translational movement, the characteristics of the sensitive part of the control device, the control axis of the sensitive part, etc.

[0053] The input module 31 is also connected to another database 36 which provides rules for the implementation of the inspection process of the part to be inspected 24.

[0054] These rules are therefore determined according to the nature of this process and include, for example, for an infrared thermography process, the minimum distance between the sensitive part of the control device and an external surface of the part to be controlled 24, an angle of inclination of the control axis of the control device, the minimum distance between two successive control poses, etc.

[0055] These rules are also called business rules and therefore correspond to the set of rules enabling the implementation of the inspection process of the part to be controlled 24.

[0056] The processing module 32 processes all the data received by the input module 31 to determine control poses. These control poses can, for example, be subsequently transmitted in the form of a plurality of control instructions for the corresponding robotic arm.

[0057] The determination of these control instructions is carried out using the determination process which will be described in more detail later.

[0058] The output module 33 allows the control instructions of the robotic arm to be transmitted using any suitable form.

[0059] For example, the output module 33 allows these control instructions to be transcribed into a digital file 38 which could be used directly or indirectly by the corresponding robotic arm in order to implement the inspection process of the part to be controlled 24. For example, this digital file 38 can be used by a computer controlling the corresponding robotic arm.

[0060] The determination device 10 allows a determination process to be implemented which will henceforth be explained with reference to [Fig.3] showing a flowchart of its steps.

[0061] Initially, it is considered that the dataset as described in relation to databases 35, 36 and the numerical model 34 are provided to the input module 31.

[0062] During an initial step 110, this input module 31 then provides this data to the processing module 32.

[0063] In a subsequent step 120, the processing module 32 then receives this data and in particular the digital model of the part to be controlled 24.

[0064] As explained previously, such a digital model may for example include a CAD representation of the part to be inspected 24. An example of such a part is schematically illustrated in [Fig.4].

[0065] On this [Fig.4], the part to be checked 24 then presents a part for example of an aircraft, for example of a turbojet blade.

[0066] The CAD representation of this part 24 can, for example, be in the form of a polygonal model. This example of a polygonal model is then illustrated in [Fig.4].

[0067] Then, the processing module 32 determines on an outer surface 41 of the received digital model a plurality of patches.

[0068] In particular, the outer surface 41 of the part to be inspected 24 has a surface of this part 24 which must be inspected by the inspection process.

[0069] This external surface 41 can then correspond substantially to the entire external surface of this part to be controlled 24 or only to a part of this external surface.

[0070] Each patch (also called a parcel) presents an area on the outer surface 41 of the part to be controlled 24. This area is associated with a control point located away from this outer surface 41 from which the area is controllable by the corresponding control device. In particular, the control point corresponds to the position of the sensitive part of the corresponding control device.

[0071] Advantageously, the dimensions and shape of each patch are defined according to those of the sensitive part of the corresponding control device. For example, when dealing with a camera having a rectangular field of view, the shape of this patch also corresponds to a rectangle, at least when projected orthogonally from it.

[0072] To determine the plurality of patches, the processing module 32 implements a plurality of substeps which will be explained below.

[0073] In particular, during a first substep 121, the processing module 32 segments the outer surface 41 of the part to be inspected 24 in order to obtain a plurality of working surfaces as illustrated in [Fig.4].

[0074] The segmentation into working surfaces is determined by the angle breaks between the normals of the polygons that constitute the outer surface 41. The break threshold is determined according to the complexity of the part.

[0075] Thus, for example, each working surface is determined so as to form a substantially flat surface of this part to be inspected.

[0076] By a substantially flat surface, we mean a surface whose limits are defined by predetermined angle breaks.

[0077] In the example of [Fig.4], five work surfaces 42a to 42d can for example be chosen during this substep 121.

[0078] During a second substep 122, the processing module 32 performs an orthogonal projection of each work surface obtained during the first substep 121.

[0079] An example of such a projection of the work surface 42a is illustrated in [Fig.5].

[0080] During a third substep 123, the processing module 32 determines a plurality of patches on the orthogonal projection so as to cover the entirety of each working surface.

[0081] In particular, during this substep 123, each patch has a 2D shape that is determined according to the sensitive part of the corresponding control device. The dimensions of this shape also correspond to those of the sensitive part of the control device.

[0082] In a particular embodiment, it is possible to introduce an offset and / or a rotation (about an axis normal to the surface) of the patches, thereby generating several sets of patches. The best set (i.e., the set satisfying the most criteria) can then be selected for the next stage of the process. One of the criteria may include, for example, the game selection with a minimal number of patches, while still ensuring the desired quality of results.

[0083] In the example of [Fig.5], each patch is then represented by a rectangle arranged on the projection plane of the corresponding work surface 42a.

[0084] The patches overlap each other in order to create the overlapping areas.

[0085] These overlapping areas extend, for example, over at least 10% of the total surface area of ​​each patch. For example, the long side of each patch is between 30 and 40 mm while its short side is between 20 and 30 mm.

[0086] In this example, the patch can form an overlap zone with another patch extending for example by 1, 2 or 3 mm.

[0087] Finally, advantageously, the set of patches have the same shape and dimensions on the orthogonal projection of each working surface.

[0088] Furthermore, during this same substep 123, the processing module 32 defines a control point associated with each patch. For example, such a control point is determined at the centroid of each patch.

[0089] In the example of [Fig.5], such a control point is formed by the diagonal intersection of the corresponding rectangles.

[0090] During a fourth substep 124, the processing module 32 determines the position of each patch on the 3D surface from their position in 2D and this for each working surface 42a to 42d.

[0091] For this purpose, rules similar to those of step 122 are applied for example.

[0092] This substep 124 then leads to 3D recovery by patches of the part to be checked 24 from the patches determined in the corresponding orthogonal projections.

[0093] An example of such a reconstruction is then illustrated in [Fig.6].

[0094] Thus, the entire external surface 41 of the part to be controlled 24 is located covered by the patches 45. Furthermore, during the 3D reconstruction of the patches, the control points associated with these patches are reconstructed in order to have a predetermined gap with the external surface 41 of the part to be controlled 24.

[0095] Thus, and as illustrated in [Fig.6], after such a reconstitution, each patch 45 forms with its associated control point a pyramid shape.

[0096] It should also be noted that the base of such a pyramid may also be deformed after 3D reconstruction. This deformation is determined by the shape of the corresponding working surface.

[0097] In a subsequent step 130, the processing module 32 checks the degree of accessibility of the patches by the corresponding control device on all the determined patches.

[0098] To this end, the processing module 32 performs an accessibility test by physically simulating collisions with respect to each of the patches 45 determined in the previous step. The physical simulation attempts to approximate a 3D model of the control device to the desired distance from the part to be controlled.

[0099] In the event of a collision between the control device and the controlled part, the physical simulation proposes an alternative patch position and orientation that avoids the collision. The physical simulation also indicates the deviations (linear and angular) between the proposed new patch and the surface of the part and the normal to the surface.

[0100] More generally, each of the accessibility tests aims to determine for each patch 45 whether the corresponding control device can access this patch 45 taking into account the dimensions and geometry of the control device on the one hand and the dimensions and geometry of the part on the other hand.

[0101] Physical simulation thus makes it possible to determine whether the control device can be physically positioned in an ideal position with respect to each patch of the part to be controlled 24. The implementation of such a physical simulation in step 130 makes it possible to maximize the quantity of patches controlled, thanks to the consideration of angular and / or linear deviations considered acceptable by the business rules.

[0102] The ideal position is defined, in particular, by the business rules. For example, it can be defined by a predefined distance between the control point of the corresponding patch 45 and a predefined point of the control device, and by a predefined angle between a predefined axis of the control device and the normal to the surface of the part at the center of the corresponding patch 45. According to such a definition, an ideal position is, for example, a distance of zero associated with an angle of 90°.

[0103] When the control device cannot be positioned to maintain the ideal position, the physical simulation determines this and provides an alternative position considered to be the closest physically accessible position. The alternative position is characterized by one or more deviations in distance and / or angle from the ideal position.

[0104] The alternative position determined by the physical simulation can vary according to rigidity parameters in position and orientation of the attraction system used to approach the surface control device.

[0105] Depending on the determined gaps and business rules, the inaccessibility of patches can be determined.

[0106] For example, when an angle deviation exceeds a predetermined angular threshold and / or a distance deviation exceeds a predetermined linear threshold, the corresponding patch 45 is considered inaccessible to the control device.

[0107] Step 130 is highly parallelizable since the accessibility test of each patch can be implemented independently. In particular, it is It is possible to simulate physical collisions between the controlled part and a multitude of control devices in parallel.

[0108] Advantageously, the corresponding control device 22 is inscribed in templates in order to have a margin.

[0109] This is schematically illustrated in [Fig.7] on which the control device 22 is represented by parallelepipeds showing its templates.

[0110] According to a particular example of the invention, the determination of inaccessible patches includes the implementation of a position and rotation (6D) attraction technique, of the control device (and in particular of its sensitive part) to the corresponding control point.

[0111] For example, the implementation of such a technique includes adding an attractive force between the sensitive part of the control device and the control point of the associated patch. Such an attractive force can be considered to be generated by a mass-spring system, for example.

[0112] When such an attractive force leads to the two points being able to come together taking into account the templates of the motorized arm and the control device as well as the geometry of the part to be controlled 24 itself, the corresponding patch is then considered to be accessible.

[0113] Otherwise, the final position and orientation of the control device obtained by the physical simulation is proposed as an alternative to the initial position of the patch.

[0114] Of course, other techniques for determining the accessibility of patches 45 are also possible.

[0115] Optionally, the processing module 32 may repeat the accessibility test several times in this case in order to propose different accessible patch alternatives.

[0116] It should also be noted that implementing an accessibility test in step 130, taking into account only the control device 22 and not the entire control installation, reduces the cost and calculation time.

[0117] In a subsequent step 140, the processing module 32 performs a filtering of all patches to remove patches considered inaccessible according to business rules such as a minimum gap and a minimum angle of the control device relative to the outer surface.

[0118] Such a case is schematically illustrated in [Fig.8] on which at least some of the patches 45 are removed.

[0119] It is also possible to shift the positioning and change the orientation along a normal axis of the patches (to make several "sets of patches") and select the "best" one according to predefined criteria such as:

[0120] - objective to minimize the number of patches;

[0121] - seek to have the best coverage in terms of accessibility;

[0122] - heating quality criterion to be applied.

[0123] In a subsequent step 150, the processing module 32 performs a scheduling of the filtered set of patches.

[0124] Such a scheduling defines the order in which these patches must be checked by the corresponding control device.

[0125] In particular, this order is determined in particular according to the rules of the trade.

[0126] Thus, for example, when the robotic arm with the corresponding control device is intended for the implementation of the infrared thermography inspection process, the adjacent patches cannot be controlled sequentially because the heating of the corresponding area in a given patch can influence the area adjacent to it, corresponding to an adjacent patch.

[0127] In such a case, the scheduling can be performed by skipping at least some of the patches on a first pass and then returning to those patches on a subsequent pass.

[0128] This is schematically illustrated in [Fig. 9] on a first pass P1 of the patches according to a particular ordering (1 patch out of 3 per column and 1 patch out of 2 per row). According to this ordering, adjacent patches are avoided. [Fig. 10] shows the ordering of the second pass P2 in which patches adjacent to the first pass are checked. In this example of ordering, six passes are required for all patches to be checked.

[0129] In a subsequent step 160, the processing module 32 determines a path for the robotic arm to reach, via the corresponding control device, the control points of the filtered set of patches according to the ordering determined in the previous step.

[0130] This step 160 thus makes it possible to determine, among all the possible positions of the robotic arms, a position that allows the patch to be reached, in other words a position respecting either the ideal position, or the alternative position determined in step 130 in relation to the patch considered (and considered as accessible).

[0131] An initial system configuration can be taken into account, such as the system elements that hold the part to be inspected or the control device, and in what orientation.

[0132] In addition, all the mechanical / physical constraints related to the control installation are also taken into account: joint limits of the robots, method of gripping the part to be inspected, and overall size of the environment. Thus, during this step 160, unlike what is carried out in step 130, all of The control installation 12 is taken into account for the simulation, and not just the control device 22 itself. Thus, the first robotic arm 14, the second robotic arm 16, and the support 18 are considered to determine the trajectory and any potential collisions.

[0133] To this end, the processing module 32 takes into account the rules relating to the mechanics of the movement of the robotic arm and the corresponding control device. The desired configuration of the robotic arm is determined using an inverse kinematic calculation from the desired position of the control device, and then validated by verifying that the robotic arm does not collide with itself or with the environment. In this case, a trajectory is calculated between the last valid configuration and a subsequent configuration. In the simplest case, the trajectory corresponds to a direct angular movement between the two configurations. If the direct trajectory presents collisions, a set of intermediate configurations is calculated using a Rapidly-Exploring Random Trees (RRT) approach. The final trajectory connects these configurations, taking into account the joint and motor limits of the robot.

[0134] By direct angular movement, we mean a movement in which each link moves towards its target angle and all the links stop simultaneously.

[0135] When no configuration allows the ideal position or the alternative position calculated in step 130 to be respected, the patch is considered to be inaccessible.

[0136] For example, this is the case of a patch covered with a jaw intended to hold the part to be inspected, or when an element of the control installation prevents access to the patch by the robotic arm or the viewing of the patch by a camera.

[0137] It should also be noted that the algorithm for finding the trajectory of the robotic arm does not calculate deviations from an ideal position and therefore does not allow for proposing an alternative position, unlike what is done in step 130. The implementation of step 130 thus allows for greater flexibility in the approach of each patch by the control device.

[0138] At the end of this step 160, the module provides a list of accessible patches and the approach time required for the robot to reach the patch, as well as a list of inaccessible patches with the reasons for their inaccessibility. This allows the operator to identify problems and modify the patch coverage or the corresponding control system.

[0139] The advantage of this step 160 is not only to provide a trajectory of the robotic arms which is calculated automatically taking into account all the geometric characteristics of the system and all possible movements, but also to determine the patches which cannot be accessed by this system.

[0140] According to one embodiment, step 160 can therefore also provide the following output:

[0141] - a list of inaccessible patches with their coordinates, which allows, for example to an operator to identify areas not inspected by the system and to address these gaps; and optionally

[0142] - a list of accessible patches with their coordinates so that the system can associate, during characterization, the patch corresponding to each characterization result (for example, an infrared image associated with the patch and therefore with the area of ​​the part characterized).

[0143] Optionally, step 160 can be repeated with a new initial configuration, for example by modifying the area of ​​the part masked by jaws for its retention, and taking into account only the patches considered inaccessible at the output of a previous iteration of step 160, in order to calculate a new trajectory.

[0144] In a subsequent step 170, the processing module 32 transforms the passage trajectory with the control points associated with each of the patches into a plurality of control instructions for the corresponding robotic arm.

[0145] These control instructions then define the control poses which must be implemented by the corresponding robotic arm.

[0146] These control instructions are determined according to the specific characteristics of each robotic arm and, for example, are determined according to the data relating to the way this robotic arm is controlled, provided by the corresponding database 35.

[0147] Then, during a final step 180, the output module 33 transcribes these control instructions into a file in any format usable by the corresponding robotic arm or by a device controlling such a robotic arm.

[0148] This file can then be stored for use when implementing an inspection process of the part to be checked 24 as explained previously.

[0149] In some embodiments, the determination process may further include a test step in which the control instructions determined in step 170 are tested on a physical control installation 12 enabling the implementation of an inspection process. During this test, at least some of the control instructions may, for example, be manually modified to change the corresponding control pose.

[0150] It is therefore understood that the present invention has a number of advantages.

[0151] First of all, the invention makes it possible to implement a process for inspecting a part to be controlled in a particularly simple way because the set of control poses for one or more robotic arms can be determined in advance.

[0152] These control poses are determined in a particularly precise and optimal manner in order to cover as much surface area as possible of the part to be inspected.

[0153] Furthermore, using the same control instructions, the inspection process of a part can be implemented several times in relation to different parts having the same dimensions and shapes.

[0154] The implementation of this process can therefore be carried out in a repeatable manner with a precision that could be determined.

Claims

Demands

1. A method for determining inspection poses of a part to be inspected (24) by an inspection device (22, 26) mounted on a robotic arm (14, 16), comprising the following steps: - supplying (110) a digital model of the part to be inspected (24); - determining (120) on an external surface (41) the digital model of a plurality of patches (45), each patch (45) having an area on said external surface (41) associated with an inspection point from which this area is inspectable by the inspection device (22, 26); - determining (130) patches inaccessible to the inspection device (22, 26) among all the patches determined; - filtering (140) the set of patches to remove the inaccessible patches (45); - determination (160) of a path for the robotic arm (14, 16) to reach, via the control device (22, 26), the control points of the filtered set of patches;- transformation (170) of the passage trajectory and control points into a plurality of control instructions for the robotic arm (14, 16).;

2. A method according to claim 1, wherein the digital model of the part to be controlled (24) is a CAD representation of that part.

3. A method according to claim 1 or 2, wherein the step of determining the plurality of patches (45) comprises the following substeps: - segmentation (121) of the outer surface (41) of the part (24) into a plurality of working surfaces; - projection (122) in 2D of each working surface; - determination (123) of a plurality of patches on the 2D projection of each working surface; - determination (124) of the 3D position of each patch on the corresponding working surface.

4. A method according to any one of the preceding claims, wherein the dimensions and shape of each patch (45) are chosen according to a sensitive part of the control device (22, 26).

5. A method according to any one of the preceding claims, wherein the patches (45) are determined on the outer surface (41) with a predetermined overlap.

6. A method according to any one of the preceding claims, wherein each control point is located at a predetermined distance from the outer surface (41) of the part to be controlled (24).

7. A method according to any one of the preceding claims, wherein the determination of inaccessible patches (45) is carried out as a function of dimensions and the motion mechanics of the robotic arm (14, 16) and / or the control device (22, 26).

8. A method according to any one of the preceding claims, wherein the determination of inaccessible patches is further carried out as a function of a minimum deviation and a minimum angle of the control device (22, 26) with respect to the part of the outer surface associated with the corresponding patch (45).

9. A method according to any one of the preceding claims, wherein the determination of inaccessible patches further includes a repositioning of patches following an accessibility test.

10. A method according to any one of the preceding claims, wherein the determination of inaccessible patches (45) includes the implementation of a 6D attraction technique of the control device (22, 26) to the corresponding control point.

11. A method according to any one of the preceding claims, further comprising a step (150) of scheduling the patches (45) of the filtered set of patches according to predetermined rules.

12. Method according to claim 11, wherein the passage trajectory is determined as a function of the patch ordering (45).

13. A computer program comprising software instructions which, when executed by a computer, implement the method according to any one of the preceding claims.

14. Device for determining (10) control poses of a part to be inspected (24) by a control device (22, 26) mounted on a robotic arm (14, 16), comprising technical means (31, 32, 33) configured to implement the method according to any one of claims 1 to 12.

15. Control device (22, 26) comprising the determination device (10) according to claim 14.

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