COOPERATION BETWEEN A ROBOT AND AN OPERATOR TO CHANGE A WORKPIECE

Description

GENERAL TECHNICAL FIELD

[0001] The invention relates to the collaboration of an operator with a robot for the purpose of manufacturing or modifying a part, in particular an aeronautical part, for example a turbomachine. STATE OF THE ART

[0002] The manufacture of aeronautical parts, such as turbomachinery, requires the intervention of an operator. This operator can be assisted by a robot to carry out specific operations.

[0003] For example, an operator drills holes in a part and the robot intervenes on each hole to perform a specific operation on each hole. Such an operation is, for example, pinning, installing a fastener, deburring, etc.

[0004] To achieve this collaboration, the robot is manipulated according to programmed actions and the operator must perform all his own actions according to the same sequence as the robot without forgetting or interfering at the risk that the robot can no longer follow the operator.

[0005] In the example of collaborative work where the operator drills holes and the robot places pins in the holes, the operator must drill these holes according to the pinning pattern programmed into the robot. If the operator does not follow this pattern, the robot will wait in front of the expected hole position until it is drilled. This results in wasted manufacturing time and can lead to manufacturing errors. PRESENTATION OF THE INVENTION

[0006] The invention proposes to overcome at least one of these drawbacks by adapting to the different actions of the operator.

[0007] For this purpose, the invention provides a method according to claim 1.

[0008] The invention is advantageously supplemented by the following characteristics: The execution of the operation comprises a movement of the robot along at least one predetermined trajectory depending on the environment of the robot the method comprises a step of monitoring the movements of the robot in order to avoid a collision with the operator, said method comprising a step of controlling the robot so that it stops, slows down its movement or determines a trajectory for avoiding the collision. the method comprises a step of generating an auditory or visual signal in the event of a risk of collision with the operator. the monitoring is implemented by means of proximity sensor(s) (13) arranged on the robot. the operation carried out by the operator is drilling a hole, the operation carried out by the robot in a hole is chosen from the following group: deburring, pin installation, rivet installation, bolting.the operation carried out by the operator is the positioning of a new part, the operation carried out by the robot being chosen from the following group: inspection of the part, application of putty.

[0009] The invention also relates to a system according to claim 8. PRESENTATION OF FIGURES

[0010] Other characteristics, aims and advantages of the invention will emerge from the following description, which should be read in conjunction with the appended drawings in which: there figure 1 illustrates an environment for implementing the invention; the figures 2 And 3 schematically illustrate steps of a method according to the invention.

[0011] In all figures, similar elements have identical references. DETAILED DESCRIPTION

[0012] There figure 1illustrates an environment in which an operator O and a robot R collaborate on the modification of a part 1. A part is typically an aeronautical part, for example of a turbomachine of an aircraft for example: The part 1 is for example positioned on a work bench 2 so as to be accessible by the robot R so that the latter can carry out an operation on the part. The therefore serves as a support for the part.

[0013] The robot R is for example a 5 / 6 / 7 axis robot of known type and will not be described in more detail because it is known to those skilled in the art. The robot R comprises an arm 3 articulated from its support 4 and comprises at its free end 5 an effector 6 or tool holder. The effector and the tool holder are chosen according to the operation to be carried out on the part.

[0014] Operator O is equipped with a tool 7 also chosen according to the operation to be carried out: a drill for a hole for example.

[0015] In the case of a hole, the R robot can perform one of the following operations: deburring, pinning, riveting, bolting. These operations can be combined for the same part, for example, one hole in one part requires riveting while another hole requires pinning.

[0016] A camera system 8 is positioned near the part 1, above or next to it in order to enable the acquisition of an image of the part being modified for comparison purposes with a model of a part. Alternatively, the camera system can be positioned on the robot R. The camera system 8 is a camera with a field of view wide enough to observe the chosen work area. The specifications of this camera are sufficient for the detection of the targeted elements. It operates by taking images at regular intervals and therefore enables detection. The camera is for example based on CCD technology.

[0017] A processing unit 9 is connected to the robot R, the processing unit 9 and the robot R each comprising a communication interface 10, 11. Communication between the robot can be wired or wireless.

[0018] Likewise, the shooting system 8 is connected to the processing unit 9.

[0019] The processing unit 9 comprises a memory 12 allowing the storage of one or more part models depending on the desired modifications. For example, when it comes to carrying out operations in holes performed by an operator, the model is a part on which the holes in which an operation is to be carried out are located. In addition, depending on the different models, trajectories to be followed by the robot are also stored. These trajectories allow the robot to position itself correctly in relation to the part so that it can carry out the operation correctly.

[0020] In order to ensure the safety of the operator in the working environment with respect to the robot R in particular, one or more proximity, force or collision sensors 13 are arranged on the robot R or in the latter's intervention environment.

[0021] Such sensors 13 make it possible, if necessary, to control the robot R so that it slows down or even stops depending on the proximity of the robot R to the operator. In addition, visual or audible alarm devices 14 may also be present to alert the operator of a danger, for example.

[0022] A user interface 15 is connected to the processing unit 9 and allows an operator O to configure the robot R and load new part models M. The user interface includes a screen and a keyboard, for example, but may consist of a touchscreen tablet or equivalent.

[0023] The processing unit also comprises a processor 16 configured to implement a method for modifying the state of a part which will be described below and in relation to the figures 2 And 3 .

[0024] Before starting the part modification operations, the robot is positioned in the work environment (step E0).

[0025] This positioning first involves the operator choosing a work area (step E01). This involves defining via the user interface 15 the area on which the robot R will operate. In particular, the operator, via the user interface 15, can indicate to the robot its future work area (at the bottom of the room, on the left, on the right, in the center, etc.). As a result, the robot positions itself remotely in front of this area, thus allowing it to visualize it correctly in order to detect the targeted elements.

[0026] Once the area has been chosen, the robot R is moved or moves itself in front of this area or to a location from which it can access the work area (step E02). This movement is controlled remotely via the user interface.

[0027] When robot R is positioned at the work area, it performs a complete flyover (step E03) of the part, using markers placed on the part. This flyover allows the robot to have an exact delimitation of its work area. These markers can take several forms and can be positioned at several strategic locations in the part. For a square part, for example, it can be considered that markers placed at the four corners of the part are sufficient.

[0028] Once the robot has been positioned in its work area, modification operations can begin.

[0029] In the following, we consider the case where an operator O must drill several holes in a part using a drill for example and the robot must perform a complementary operation in each hole made by the operator O. The robot R therefore collaborates with the operator O to modify the state of the part. As mentioned above, the operations of the operator and the robot R can be varied and the method can be applied to all collaborations requiring both operations performed by the operator O and by the robot R at the same locations of the part or not.

[0030] An operator begins by drilling one or more holes in the part (step E1) and a detection of the drilling of a hole is carried out (step E2). This detection consists of acquiring (step E21) images of the part in order to evaluate whether its state is modified. The acquisition can be continuous or implemented at a well-chosen frequency. Advantageously, the acquisition is implemented by means of the image capture system 8.

[0031] Then, it is evaluated whether in the hole that has just been made the robot R must perform a complementary operation to that of the operator O (steps E3 and E4) and if this is the case, the robot R is commanded (step E5) to perform the predefined complementary operation in the hole that has been detected, otherwise the robot R waits (step E6) for a hole to be drilled again.

[0032] To assess whether the robot R should perform a complementary operation, the acquired image(s) are compared with a part model comprising the part as it is to be modified. For example, the processing unit compares the image acquired by the imaging system 8 and compares it with a theoretical 3D model of the part. The deviations are highlighted and information about a deviation between the image and the model is obtained.

[0033] The modification that the robot must perform where the operator O has modified the part is pre-programmed in advance and will not be detailed here. Also, to reach the ideal position to perform the operation, the robot R follows a predetermined trajectory. The operations to be performed as well as the trajectories are stored in the memory 12 of the processing unit 9. The predetermined trajectory depends on the environment for the robot R to reach the position and is determined by taking into account the information from the sensors 13 in order to avoid any collisions. The robot R therefore needs the coordinate of the position as well as the type of operation to be performed on this position.

[0034] After performing the operation, the robot moves into a waiting position for a new hole to be drilled. This waiting position is also reached if, after the hole has been detected, no further operation is required.

[0035] In addition and in parallel with the various steps aimed at modifying the part, the movements of the robot R are monitored (step E7) in order to avoid a collision between the operator and the robot R. In the event that a risk of collision is identified, the robot R can either stop (step E8) or slow down its movement (step E9). In addition or as an alternative, an audible or visual signal can be emitted (step E10) to alert the operator that there is a danger. In addition, the robot can adapt its movement in order to avoid the collision (step E11).

Claims

1. Method for modifying the condition of a component, typically an aeronautical component and in particular a turbomachine component, by means of a robot (R) controlled by a processing unit (9), a component (1) being placed in a working environment to which an operator (O) has access in order to perform operations on the component, said method comprising: - performing one or more operations on the component by the operator; and the following steps, implemented by the processing unit (9): - detecting (E2) an operation performed on the component by the operator, comprising acquisition (E21) of at least one image of the workpiece; and comparing (E3) the image of the workpiece with a workpiece model, characterised in that said model comprises positions at which operations are to be performed by the robot following an operation by the operator; and if, at the location on the component where the operation was performed, the robot must perform an operation; - execution (E5) by the robot (R) of an operation complementary to that of the operator and predefined on said component at the location on the component where the operator performed the operation; after performing the complementary operation or if, after the operation has been detected, it is not necessary for a complementary operation to be performed: placing the robot in a waiting position until a new operation on the component is performed by the operator.

2. Method according to claim 1, wherein the execution of the operation includes moving the robot along at least one predetermined trajectory depending on the robot's environment.

3. Method according to one of the preceding claims, comprising a step of monitoring (E7) the movements of the robot in order to avoid a collision with the operator, said method comprising a step of controlling the robot so that it stops, slows down its movement or determines a collision avoidance trajectory.

4. Method according to the preceding claim, comprising a step of generating (E10) an audible or visual signal in the event of a risk of collision with the operator.

5. Method according to claim 3, in which monitoring is implemented by means of proximity sensor(s) (13) located on the robot.

6. Method according to one of the preceding claims, wherein the operation performed by the operator is drilling a hole, and the operation performed by the robot in a hole is selected from the following group: deburring, pinning, riveting, bolting.

7. Method according to one of claims 1 to 5, wherein the operation performed by the operator is the positioning of a new component, the operation performed by the robot being selected from the following group: inspection of the component, application of sealant.

8. System comprising a robot (R) and a processing unit (9) configured to control the robot according to the steps performed by the processing unit as defined by the preceding claims.