Additive manufacturing device including robot for characterizing protective gas flow
The modular robot system addresses the challenge of non-uniform shielding gas flow in additive manufacturing by using adjustable arms to characterize gas flow properties, enhancing the quality of manufactured parts through improved uniformity and precision.
Patent Information
- Application Number
- JP2024554146
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-03-22
- Filing Date
- 2023-02-02
- Publication Date
- 2025-04-15
AI Technical Summary
Existing additive manufacturing devices face challenges in ensuring uniformity of the shielding gas flow, leading to incomplete or incorrect mapping of gas flow, which can result in manufacturing defects such as oxidation, fume, and sputter issues.
A modular robot system is introduced that can characterize the shielding gas flow within the additive manufacturing chamber. This robot features adjustable moving arms composed of multiple physical separation modules, allowing it to adapt to varying chamber dimensions and flow areas, ensuring precise measurement of gas flow properties.
The modular robot system effectively characterizes the shielding gas flow, ensuring uniformity and improving the quality of manufactured parts by providing detailed measurements of gas flow properties, thus reducing manufacturing defects.
Smart Images
Figure 2025510602000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to an additive manufacturing device that includes a robot dedicated to controlling a shielding gas flow generated in a manufacturing enclosure of the additive manufacturing device.
[0002] In particular, the present invention is applicable to additive manufacturing devices that are intended to carry out metal powder bed laser fusion additive manufacturing methods. [Background technology]
[0003] Additive manufacturing combines methods for producing parts in three dimensions by the successive addition of layers of material based on a digital model, without the use of tools. The term "additive" is used in contrast to traditional methods (e.g. machining), which are based on the removal of material.
[0004] Additive manufacturing methods, also called three-dimensional printing methods (e.g. selective laser melting, selective laser sintering, stereolithography, etc., among others), are intended to be methods by which three-dimensional components are produced from a substrate by chemical and / or physical actions. The substrate is generally liquefied or melted, at least in areas, in order to harden the substrate in order to form the part to be manufactured.
[0005] In particular, methods are known that utilize a laser beam and a substrate in the form of a powder, which is melted locally, layer by layer, by selectively sweeping the laser over the powder bed according to a pre-set digital model. Furthermore, the term powder bed laser fusion is used. The fusion method heats the substrate to a temperature above the melting temperature. When the laser beam interacts with the powder bed, it creates a column of metal vapor, called a keyhole, in the area melted by the beam, as seen in the laser welding method. Due to the extension of the metal vapor towards the outside of the keyhole, fumes and metal spatter are generated that are extracted from the powder bed and the pool of molten metal.
[0006] However, metal sputter contains oxides, and melting of the oxides during production of a part by additive manufacturing can cause manufacturing defects in the part (e.g., visual defects, metallurgical defects, density defects, and / or porosity defects).
[0007] It is known to carry out additive manufacturing processes in additive manufacturing chambers in order to control the characteristics and quality of the manufactured parts. These chambers are closed enclosures in which the gas atmosphere is controlled. The manufacturing enclosure is provided with a shielding gas supply system connected to the internal volume of the manufacturing chamber in order to generate in the manufacturing enclosure a gas flow that protects the manufacturing area against the effects of oxidation, fumes and spatter.
[0008] Uniformity of gas flow within the additive manufacturing chamber can ensure the quality of the manufactured parts, especially for alloys that produce large amounts of fumes or for manufacturing large volumes of parts requiring production times of several hours or even days.
[0009] However, gas flows generated in additive manufacturing chambers are known to be non-uniform or less than uniform, and information regarding the non-uniformity of the shielding gas flow is generally not available.
[0010] In fact, lack of uniformity of the shielding gas over the entire surface can cause the emission of fumes and spatters in the less effective interaction zone. These phenomena have been described in numerous publications, including an article entitled "Influence of the shielding gas flow on the removal of process by-products in the selective laser melting process" by A. Ladewig et al. (Additive Manufacturing, vol. 10, 2016, pp. 1-9) and an article entitled "Gas flow effects on selective laser melting (SLM) manufacturing performance" by B. Ferrar et al. (Journal of Materials Processing Technology vol. 212, 2012, pp. 355-364).
[0011] For example, AMPhilo (Solid Freeform Fabrication 2017: Proceedings of the 28th th There are systems to map the gas flows generated in additive manufacturing chambers, such as those described in the publication entitled "A study into the effects of gas flow inlet design of the renishaw am250 laser powder bed fusion machine using computational modelling" by the Annual International Solid Freeform Fabrication Symposium, pages 1203 to 1219. These systems are typically equipped with a probe that measures the flow rate. Typically, these systems have a probe supported by a robot that can move in the generated flow above the manufacturing area.
[0012] However, these robots are not modular and are configured based on the dimensions of the chamber and manufacturing area. These dimensions vary by additive manufacturing machine manufacturer, and further by the application intended by the user and the dimensions of the parts to be manufactured. Thus, characterization of gas flows requires the construction of a measurement robot dedicated to each existing chamber configuration, which complicates the installation of the characterization system.
[0013] Furthermore, the movement possible in the volume of the additive manufacturing chamber may be limited, resulting in incomplete or inaccurate mapping of the gas flows. Summary of the Invention [Problem to be solved by the invention]
[0014] The object of the present invention is to propose an additive manufacturing device provided with a robot characterizing a shielding gas flow that overcomes the above mentioned drawbacks, in particular allowing the robot to be easily adapted to the dimensions of the manufacturing room. [Means for solving the problem]
[0015] The solution according to the invention then comprises a device for additively manufacturing at least one part, comprising: a production room including a production area in an interior volume of the production room; - illumination means adapted to illuminate at least a portion of a production area corresponding to a cross section of said part; a gas supply system connected to an interior volume of the production chamber and configured to generate a shielding gas flow for the production region when supplying gas to the production chamber; a modular robot configured to characterize at least a portion of a shielding gas flow; Including, The modular robot is a measurement arm including at least one measurement probe configured to measure at least one physical variable characteristic of the gas flow; a first chassis supporting the measurement arm; a first movement arm associated with the first chassis and extending parallel to a first direction; first drive means for the first chassis capable of moving the first chassis in translation along the first moving arm; a second chassis for fixing the first moving arm; and a second movement arm associated with the second chassis and extending parallel to the second direction; and second drive means for the second chassis capable of moving the second chassis and the first moving arm in translation along the second moving arm; Including, A device characterized in that at least one of the first and second moving arms of the modular robot includes a number of physically separate modules connected to each other by detachable coupling means such that the overall length of the first moving arm and / or the overall length of the second moving arm can be adjusted by removing or adding one or more modules.
[0016] In some cases, the invention may include one or more of the following features. The first direction is perpendicular to the second direction. the modular robot comprises third drive means for the measuring arm fixed to the first chassis, the third drive means being capable of moving the measuring arm in translation parallel to a third direction orthogonal to the first direction. - the modular robot further includes a third chassis and a third moving arm associated with the third chassis, the third moving arm extending parallel to the second moving arm and the first moving arm being fixed to the third chassis, the modular robot includes a fourth drive means for the third chassis (110) capable of moving the third chassis in translation along the third moving arm, and a means for synchronizing the second drive means and the fourth drive means configured to synchronize the translational movement of the second chassis and the third chassis. the modular robot includes fifth drive means capable of rotating the second chassis about the second arm or of rotating the second arm on itself; the robot includes angular adjustment means configured to adjust the positioning of the measurement probe by pivoting on and / or by rotating about the first moving arm. The detachable connecting means connecting one module to another module comprise at least one intermediate part and fixing means for fixing this intermediate part both to the one module and to the other module. The detachable coupling means are configured to couple one module to another by push-fit and / or by magnetic connection. Each of the first moving arm, the second moving arm and / or the third moving arm and / or the measuring arm of the modular robot comprises 2 to 40 modules, preferably 2 to 10 modules. The modules forming the first moving arm, the second moving arm and / or the third moving arm and / or the measuring arm of the modular robot have a length between 25 mm and 500 mm. - each of the first drive means, the second drive means, the third drive means, the fourth drive means and / or the fifth drive means comprises a motor interacting with a rack and pinion drive system, wherein the one or more moving arms have a toothed surface intended to mesh with a toothed pinion, or the friction drive system comprises a pinion coated with a deformable material that frictionally interacts with the one or more moving arms. The measurement probe is configured to measure the volume flow rate and / or the velocity of the gas flow, in particular the measurement probe comprises a Pitot tube or a hot wire system. - the measuring arm comprises at least one additional measuring probe configured to measure the temperature of the gas flow and / or the oxygen content of the gas flow, or the measuring probe is configured to measure the temperature of the gas flow and / or the oxygen content of the gas flow. - The device is configured for powder bed laser fusion additive manufacturing, and the device a production table configured to receive a substrate in the form of a layer of metal powder in a production direction z for successively depositing and fusing layers of substrate; spreading means for spreading this layer so as to form a powder bed extending in a plane perpendicular to the production direction; at least one laser source configured to irradiate the powder bed in a manufacturing area corresponding to a cross-section of the metal part and selectively melt the powder bed; A means for moving the production table parallel to the production direction; Includes.
[0017] According to another aspect, the present invention provides a method for characterizing a flow generated by the device described above, comprising the steps of: a) determining at least one dimension of a manufacturing area; b) selecting modules from a given set of modules to form at least one of the first moving arm and the second moving arm of the modular robot to set a total length of the first moving arm and / or a total length of the second moving arm according to the dimensions determined in step a); c) positioning the robot in the manufacturing room such that the measurement probe assumes a first position; d) supplying gas to the manufacturing chamber to generate a shielding gas flow for the manufacturing area; e) obtaining a first measurement of at least one physical variable indicative of the flow by a measurement probe; f) moving the first chassis in translation along the first movement arm and / or moving the second chassis in translation along the second movement arm such that the measurement probe assumes a second position; g) obtaining a second measurement of the at least one physical variable by the measurement probe; The present invention relates to a method comprising the steps of:
[0018] The invention will now be explained in more detail with the aid of the single accompanying drawing, given as a non-limiting example. [Brief description of the drawings]
[0019] [Figure 1] FIG. 1 shows a schematic of a facility for carrying out an additive manufacturing method according to one embodiment of the present invention. [Diagram 2] FIG. 2 shows a three-dimensional view of a modular robot according to one embodiment of the present invention. [Diagram 3] FIG. 3 shows a top view of the robot according to FIG. [Figure 4] FIG. 4 shows a three-dimensional view of a modular robot according to another embodiment of the present invention. [Diagram 5] FIG. 5 shows a connection means for connecting the movement arm modules according to one embodiment of the present invention. [Figure 6] FIG. 6 shows a connecting means for connecting movement arm modules according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Figure 1 shows an exemplary embodiment of an additive manufacturing method in a production room. The invention applies in particular to powder bed laser fusion. In this case, the means for irradiating the substrate is a laser source. It is also possible to envisage using an electron beam as the irradiation means.
[0021] In operation, the powder bed 14 forming the substrate is melted by sweeping a laser beam 9 obtained using a head 11 or scanner, for example, including a steerable folding mirror. The head 11 is controlled by digital commands that direct the laser beam towards the area of the powder bed 14 to be melted. The laser beam 9 can be generated by at least one laser source selected from a CO2 laser, a fiber laser or a disk laser, a diode laser.
[0022] The device according to the invention comprises an enclosure called production chamber 8. The chamber 8 is intended to contain a gas atmosphere which can be formed by an inert gas (for example argon or nitrogen). A shielding gas is distributed to the chamber by a gas supply system comprising one or more gas inlets. Preferably, at least one gas inlet 13 distributes the shielding gas above the powder bed 14, preferably in a plane substantially perpendicular to the production direction z in which the layers of substrate are successively deposited and melted. Preferably, the gas flow enters in a flow direction x perpendicular to the direction z.
[0023] Preferably, the shielding gas comprises at least one inert component selected from argon, helium, nitrogen, Optionally, the shielding gas may comprise additional components (e.g., carbon dioxide).
[0024] Advantageously, the chamber is equipped with a system for extracting fumes and spatters, preferably located on the side of the chamber opposite the gas inlet 13. A flow direction x is directed from the first orifice 13 towards at least one extraction orifice of the extraction system.
[0025] Preferably, the orifices 12 distribute the shielding gas below the protective window 10 to avoid contamination of the protective window 10 with fumes from the layer melting operation.
[0026] Preferably, the production of the parts starts after a production chamber purging step to obtain a gas atmosphere having an oxygen content of less than 0.1% by volume, the production chamber including, for example, an electrochemical or zircon type sensor configured to measure the oxygen content of the production chamber and thus allow or stop production.
[0027] During the production of a part, a powder bed 14 is spread by a scraper 2 on a production table 4. Powder is fed by a tray 1 which is raised by a piston 3. Excess powder falls into a container 6.
[0028] After each layer is produced, the production table is lowered in the direction opposite to the production direction z, from a height corresponding to the height of the new layer of powder deposited on the previous layer. After each layer is deposited, the powder bed is selectively swept with a laser beam according to a digital model that determines the three-dimensional shape of the part. A layer of metal powder is selectively melted in a predetermined production area that corresponds to a cross-section of the metal part to be produced, this cross-section being perpendicular to the production direction z. The steps of depositing and melting the bed and moving the table are repeated at least once until the part is built up by superposition in the direction z of the various melting cross-sections. It should be noted that preferably a new layer is deposited after the previous layer has solidified. It should be noted that the powder is preferably melted in the overall melting direction opposite to the flow direction y.
[0029] A quantity of unmelted powder 5 remains on the production bed 4 around the part 7 to be produced. Typically, the thickness of each production layer ranges between 10 μm and 120 μm, depending on the quality and speed of production of the part or parts to be realized. Furthermore, this layer thickness depends on the grain size of the powder. The metal powder used is preferably formed from grains having a diameter ranging between 10 μm and 70 μm.
[0030] The substrate 14 may be selected, for example, from alloy steel, non-alloy steel, especially stainless steel, carbon steel, aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys.
[0031] Figure 2 illustrates a particular embodiment of a modular robot 100 configured to characterize at least a portion of the shielding gas flow generated in the manufacturing chamber 8. Figure 3 is a top view of the robot. In this embodiment, the modular robot 100 is a Cartesian coordinate robot movable along three axes parallel to the three directions x, y, z of a Cartesian coordinate system. In operation, the directions x, y are preferably orthogonal to the direction z and are contained in a plane parallel to the manufacturing area corresponding to a cross-section of the part to be manufactured. The third direction z is preferably vertical.
[0032] The modular robot 100 comprises a measurement arm 101 to which at least one measurement probe 102 is fixed, the measurement probe being configured to measure at least one physical variable characteristic of the gas flow. A first chassis 103 supports the measurement arm 101, and a first moving arm 105 is associated with the first chassis 103 and extends parallel to a first direction y. The robot 100 comprises first drive means 106 capable of moving the first chassis 103 in translation along the first moving arm 105.
[0033] The robot 100 further comprises a second chassis 104 to which a first moving arm 105 is fixed. A second moving arm 107 is associated with the second chassis 104 and extends parallel to a second direction x. Second drive means 108 are able to move the second chassis 104 in translation along the second moving arm 107 and the first moving arm 105 fixed to the first chassis, so that the measuring arm 101 can move in two directions x, y.
[0034] According to the invention, at least one of the first moving arm 105 and the second moving arm 107 of the modular robot 100 comprises a number of physically separated modules 105a, 105b, 107a, 107b connected one after the other by detachable connecting means 109 so that the overall length of the first moving arm 105 and / or the overall length of the second moving arm 107 can be adjusted by removing or adding one or more modules 105a, 105b, 107a, 107b. In the case of the first moving arm 105, the modules 105a, 105b are connected one after the other in a first direction y. In the case of the second moving arm 107, the modules 107a, 107b are connected one after the other in a second direction x. The overall length of the first arm 105 measured in the first direction y corresponds to the sum of the individual lengths of the modules forming the first arm 105. The overall length of the second arm 107 measured in the second direction x corresponds to the sum of the individual lengths of the modules that form the second arm 107 .
[0035] As a result, the length of the movement arms can be easily adapted to changes in the dimensions of the chamber and / or the flow area to be characterized. A robot designed for one chamber can be used in another chamber by modifying the number and / or the length of the modules forming the arms, which allows for greater flexibility and speed of adaptation, regardless of the dimensions of the chamber and the production area to be characterized.
[0036] Preferably, each of the first moving arm 105 and the second moving arm 107 of the modular robot 100 includes multiple modules, which allows for adaptability in two lateral directions of the chamber.
[0037] Advantageously, the modular robot 100 comprises third drive means 111 for the measuring arm 101. The third drive means 111 are fixed to the first chassis 103 and are capable of moving the measuring arm 101 in translation parallel to a third direction z, thus allowing the measuring probe 102 to be moved in a third direction.
[0038] Preferably, the modular robot 100 further comprises a third chassis 110 and a third moving arm 112 associated with the third chassis 110, the third moving arm 112 extending parallel to the second moving arm 107. The first moving arm 105 is fixed at one end to the second chassis 104 and at the other end to the third chassis 110. The fourth drive means 113 is configured to move the third chassis 110 in translation parallel to the third moving arm 112. This improves the robustness of the robot and the control of the robot's movements. Preferably, the robot 100 comprises means for synchronizing the second drive means 108 and the fourth drive means 113 configured to synchronize the translational movements of the second chassis 104 and the third chassis 110.
[0039] It should be noted that the third moving arm 112 and / or the measuring arm 101 are preferably formed from multiple modules in order to adjust the length of these arms.
[0040] According to one possibility, the moving arm of the robot 100 is mounted on a fixed foot 114 which is height adjustable, ie which makes it possible to adjust the positioning of the moving arm of the robot in the third direction z.
[0041] In particular, each of the first moving arm 105, the second moving arm 107 and / or the third moving arm 112 and / or the measuring arm 101 of the modular robot 100 comprises 2 to 40 modules, preferably 2 to 10 modules. It should be noted that the measuring arm 101 can be formed from only one module.
[0042] In particular, the modules forming the first moving arm 105, the second moving arm 107 and / or the third moving arm 112 and / or the measuring arm 101 of the modular robot (100) have a length between 25 mm and 500 mm.
[0043] 4 illustrates a particular embodiment in which the modular robot 100 is a polar robot capable of translational and rotational movement in a cylindrical coordinate system x, r, θ. In particular, the modular robot 100 comprises fifth drive means 115, 108 capable of rotating the second chassis 104 about the second arm 107 or of rotating the second arm 107 on itself. Preferably, the first direction corresponds to the radial direction r and the second direction x corresponds to the vertical direction. The rotational movement of the first chassis 103 changes the angular positioning θ.
[0044] According to one possibility applicable to various embodiments of the invention, the robot 100 may comprise angular adjustment means 116 for angularly adjusting the positioning of the measurement probe 102 by pivoting on the first moving arm 105 and / or by rotating about the first moving arm 105. This allows aligning the measurement probe 102 with the direction of the shielding gas flow.
[0045] Figures 5 and 6 illustrate possible embodiments of detachable connecting means 109 for connecting the modules to each other. The connecting means may comprise one or more intermediate parts 120 and fastening means 121 for fastening the intermediate part 120 to both one module 105a and another module 105b. Figure 5 shows an example of parts 120 in the form of clips 121 screwed to each arm. According to an alternative, the detachable connecting means 109 may be configured to connect the modules by pressing and / or by magnetic connection. Alternatively or additionally, the connecting means 109 may comprise a foolproof function.
[0046] According to one embodiment, the drive means of the modular robot 100 each include a motor that interacts with a drive system for the associated chassis. The drive system may be a rack and pinion drive system. In this case, the movement arm is coupled to a toothed pinion having a toothed surface and set in rotation by a motor. Meshing According to another possibility, the drive system may operate by friction. In this case, a pinion covered with a deformable material is set in rotation by a motor and interacts by friction with a non-deformable surface of the associated moving arm. It should be noted that the device according to the invention can utilize a monopolar or bipolar stepper motor. The use of a DC motor can also be envisaged.
[0047] Preferably, the modular robot 100 is configured to move in increments of at most 1 mm in one direction and / or the other. Typically, movements may be performed in smaller increments, down to the increments of the motors used (in particular 0.02 mm).
[0048] In the context of the present invention, the measurement probe 102 may be any means capable of measuring a physical variable indicative of the uniformity of the gas flow. Preferably, the measurement probe 102 is configured to measure the volumetric flow rate and / or the velocity of the gas flow, in particular the measurement probe 102 comprises a pitot tube or a hot wire system.
[0049] It is also conceivable to equip the measuring arm 101 with at least one additional measuring probe configured to measure the temperature of the gas flow and / or the oxygen content of the gas flow. The measuring probe 102 itself may be configured to measure the flow rate and another physical variable (e.g. the temperature of the gas flow and / or the oxygen content of the gas flow).
[0050] Advantageously, the device according to the invention comprises a control and command unit and means for transmitting command and measurement signals between the control and command unit and the modular robot 100. Preferably, the control and command unit comprises at least one of a microcontroller, a microprocessor, a computer. The control and command unit is configured to control the movements of the modular robot 100 and to acquire the measurements taken by the measurement probe 102. The transmission means may be wired or wireless, preferably by a WiFi connection or Bluetooth or any other wireless protocol.
[0051] Preferably, the drive means and the control and command unit are powered by a battery, which makes the device autonomous. It is also possible to envisage connecting the device to a power grid in order to perform flow characterisation over long periods of time.
[0052] The production area in which the gas flow is to be characterized may have characteristic dimensions ranging from 50 mm to 800 mm in a plane corresponding to the cross-sectional plane of the part to be produced. The device according to the invention can be adapted to these different dimensions by the modularity of the movement arms.
Claims
1. 1. A device for additively manufacturing at least one part, comprising: a production chamber (8) containing a production area (7) in its internal volume, - illumination means (9) configured to illuminate at least a portion of said production area (7) corresponding to a cross-section of said component; a gas supply system connected to the internal volume of the production chamber (8) and configured to generate a shielding gas flow for the production area (7) when supplying gas to the production chamber (8); a modular robot (100) configured to characterize at least a portion of said shielding gas flow; Including, The modular robot (100) comprises: a measuring arm (101) comprising at least one measuring probe (102) configured to measure at least one physical variable characteristic of said gas flow; a first chassis (103) supporting said measuring arm (101); a first movement arm (105) associated with said first chassis (103) and extending parallel to a first direction (r, y); first drive means (106) for said first chassis (103) capable of moving said first chassis (103) in translation along said first moving arm (105); a second chassis (104) to which the first moving arm (105) is fixed; a second movement arm (107) associated with said second chassis and extending parallel to a second direction (x); second drive means (108) for said second chassis (104) capable of moving said second chassis (104) and said first moving arm (105) in translation along said second moving arm (107); Including, 1. A device, characterized in that at least one of the first moving arm (105) and the second moving arm (107) of the modular robot (100) comprises a number of physically separated modules (105a, 105b, 107a, 107b) connected to each other by detachable connecting means (109) such that the overall length of the first moving arm (105) and / or the overall length of the second moving arm (107) can be adjusted by removing or adding one or more modules (105a, 105b, 107a, 107b).
2. 2. The device of claim 1, wherein the first direction (y, r) is orthogonal to the second direction (x).
3. 3. The device according to claim 1 or 2, characterized in that the modular robot (100) comprises third drive means (111) for the measuring arm (101) fixed to the first chassis (103), the third drive means (111) being capable of moving the measuring arm (101) in translation parallel to a third direction (z) perpendicular to the first direction (x).
4. 4. The device according to claim 1, further comprising a third chassis (110) and a third moving arm (112) associated with the third chassis (110), the third moving arm (112) extending parallel to the second moving arm (107) and the first moving arm (105) being fixed to the third chassis (110), the modular robot (100) further comprising fourth drive means (113) for the third chassis (110) capable of moving the third chassis (110) in translation along the third moving arm (112), and means for synchronizing the second drive means (108) and the fourth drive means (113) configured to synchronize the translational movements of the second chassis (104) and the third chassis (110).
5. 3. The device according to claim 1 or 2, characterized in that the modular robot (100) comprises a fifth drive means (115, 108) capable of rotating the second chassis (104) about the second arm (107) or of rotating the second arm (107) on its own.
6. The device according to any one of claims 1 to 5, characterized in that the robot (100) comprises angular adjustment means configured to adjust the positioning of the measurement probe (102) by pivoting on and / or by rotating around the first moving arm (105).
7. A device according to any one of claims 1 to 6, characterized in that the detachable connecting means (109) connecting one module (105a, 107a) to another module (105b, 107b) comprise at least one intermediate part (120) and fixing means (121) for fixing the intermediate part (120) both to the one module and to the other module.
8. The device according to any one of claims 1 to 7, characterized in that the detachable coupling means (109) are configured to couple one module (105a, 107a) to another module (105b, 107b) by push-fitting and / or by magnetic connection.
9. The device according to any one of claims 1 to 8, characterized in that each of the first moving arm (105), the second moving arm (107) and / or the third moving arm (112) and / or the measuring arm (101) of the modular robot (100) comprises 2 to 40 modules, preferably 2 to 10 modules.
10. The device according to any one of claims 1 to 9, characterized in that the modules forming the first moving arm (105), the second moving arm (107) and / or the third moving arm (112) and / or the measuring arm (101) of the modular robot (100) have a length comprised between 25 mm and 500 mm.
11. 11. The device according to claim 1, characterized in that each of the first drive means (106), the second drive means (108), the third drive means (111), the fourth drive means (113) and / or the fifth drive means (115) comprises a motor interacting with a rack-and-pinion drive system, the one or more moving arms having a toothed surface intended to mesh with a toothed pinion, or a friction drive system comprising a pinion coated with a deformable material that frictionally interacts with the one or more moving arms.
12. The device according to any one of claims 1 to 11, characterized in that the measurement probe (102) is configured to measure the volumetric flow rate and / or the velocity of the gas flow, in particular the measurement probe (102) comprises a Pitot tube or a hot wire system.
13. The device according to any one of claims 1 to 12, characterized in that the measuring arm (101) comprises at least one additional measuring probe configured to measure the temperature of the gas flow and / or the oxygen content of the gas flow, or the measuring probe (102) is configured to measure the temperature of the gas flow and / or the oxygen content of the gas flow.
14. the device is configured for powder bed laser fusion additive manufacturing; a production table (4) configured to receive a substrate (14) in the form of a layer of metal powder in a production direction z for successively depositing and melting layers of substrate; - spreading means for spreading said layer so as to form a powder bed extending in a plane perpendicular to the production direction (z); at least one laser source configured to irradiate the powder bed in the manufacturing area (7) corresponding to a cross-section of the metal part, thereby selectively melting the powder bed; - means for moving said production table (4) parallel to said production direction (z); A device according to any one of claims 1 to 13, characterized in that it comprises
15. A method for characterising a flow generated by a device according to any one of claims 1 to 14, comprising the steps of: a) determining at least one dimension of a production area; b) selecting modules from a given set of modules for forming at least one of the first moving arm (105) and the second moving arm (107) of the modular robot (100) so as to set a total length of the first moving arm (105) and / or a total length of the second moving arm (107) according to the dimensions determined in step a); c) positioning said robot in a manufacturing room such that a measurement probe (102) assumes a first position; d) supplying gas to said production chamber (8) to generate a shielding gas flow for said production area (7); e) obtaining a first measurement of at least one physical variable indicative of said flow by said measurement probe (102); f) moving the first chassis (103) in translation along the first moving arm (105) and / or moving the second chassis (104) in translation along the second moving arm (107) such that the measurement probe (102) assumes a second position; g) obtaining a second measurement of at least one physical variable by said measurement probe (102); The method includes: