Robot-assisted laser additive manufacturing system for interlaminar reinforcement of continuous fiber composites

Abstract

The present invention discloses a robot-assisted laser additive manufacturing system for interlayer reinforcement of continuous fiber composites, which belongs to the field of additive manufacturing technology. A printing unit is connected to the end of the robot arm of the manufacturing system. The controller accurately controls the movement speed of the printing unit, the laser power of the laser unit and the pressure generated by the pressure roller unit. The laser beam is used to heat the composite filament to a semi-molten state and is flattened into a strip under the action of the pressure roller unit. As the printing unit moves, the bonded composite filament generates traction on the unmelted wire material, so that it is continuously sent out from the wire storage disk through the wire feeding unit. The printing platform provided on the positioner can receive the formed composite filament, and finally bond and stack them layer by layer into a high-density part. The present invention improves the bonding performance between the layers of the parts, and expands the forming freedom and working space of the printing unit. Thereby, both the interlayer reinforcement of continuous fiber composite materials and the high-performance additive manufacturing of large-sized complex parts can be achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing, and more specifically, relates to a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement. Background Art

[0002] Additive manufacturing (also known as 3D printing) is a new manufacturing technology developed in the late 1980s. It mainly uses computers to build three-dimensional digital models and relies on the accumulation of materials layer by layer to obtain the final parts.

[0003] Continuous fiber reinforced thermoplastic composites (CFRTPCs) have the advantages of high strength, long life, corrosion resistance and green recyclability. They are widely used in aerospace, transportation and high-precision processing equipment, and are gradually developing into alternative materials that may replace traditional plastics and metals.

[0004] Achieving the correct fiber orientation during the forming process of CFRTPCs is crucial to improving the mechanical properties of parts. Traditional CFRTPCs forming processes such as compression molding, stamping molding, vacuum forming, fiber winding, extrusion molding, and airbag-assisted molding often require expensive molds and it is difficult to produce complex parts that meet fiber orientation requirements. The customizable path planning strategy and layer-by-layer bonding molding principle based on additive manufacturing technology can further optimize the fiber orientation of CFRTPCs, which overcomes the limitations of traditional molding methods. Therefore, in order to bypass the long and expensive processing process, additive manufacturing technology of continuous fiber reinforced thermoplastic composites has become a hot area in academia and industry.

[0005] In recent years, fused deposition modeling (FDM) or fused filament fabrication (FFF) has become the main process for additive manufacturing of continuous fiber reinforced thermoplastic resin composite materials due to its low equipment development cost and ease of use. Patent publication number W02016 / 041449A1 discloses a fused deposition 3D printer and a printing method thereof. In this process, a composite filament of thermoplastic resin and fiber is fed into a heated nozzle, where the resin is melted by a temperature higher than its glass transition temperature but lower than its melting point, and then an adhesive filament is extruded from the nozzle. By controlling the moving direction and speed of the nozzle, the filament extruded from the nozzle is bonded to a substrate or other materials, and finally the desired parts are formed by bonding layer by layer.

[0006] However, due to the presence of pores in the printing process of continuous fiber composite parts printed using traditional FDM, the shear strength between the parts is low, resulting in their mechanical properties generally being lower than those of conventional molding processes. In response to this, patent publication number CN111633979A discloses a Z-direction reinforcement method and manufacturing equipment for additive manufacturing of continuous fiber composite materials; patent publication number CN111497225A discloses a nozzle, printer and printing method suitable for continuous fiber reinforced composite materials, which can use temperature and external force of the nozzle to improve the bonding effect within the fiber bundle and between layers and reduce the generation of voids; patent publication number CN114683537A discloses a method for preparing carbon nanotube / continuous fiber reinforced composite materials using plasma and melt deposition technology, which uses plasma technology to spray carbon nanotubes on the surface of continuous fibers to improve the bonding strength between the continuous fibers and the matrix, thereby improving the mechanical properties of continuous fiber reinforced composite products; patent publication number CN111497225A discloses a nozzle, printer and printing method suitable for continuous fiber reinforced composite materials, which can use temperature and external force of the nozzle to improve the bonding effect within the fiber bundle and between layers and reduce the generation of voids; patent publication number CN114683537A discloses a method for preparing carbon nanotube / continuous fiber reinforced composite materials using plasma and melt deposition technology, which uses plasma technology to spray carbon nanotubes on the surface of continuous fibers to improve the bonding strength between the continuous fibers and the matrix, thereby improving the mechanical properties of continuous fiber reinforced composite products; Patent 4248437A discloses a 3D printing method for continuous fiber braided body reinforced fiber composite materials, which combines the weaving and needle punching processes of the textile industry with 3D printing technology, and strengthens its bonding with the thermoplastic resin by pre-treating the continuous fiber braided body. At the same time, Z-direction needle punching enables the fibers to enhance the interlayer bonding force, which can significantly improve the strength of the composite material structure; Patent publication number WO2018 / 157841A1 discloses a method for additive manufacturing of interlayer reinforced continuous fiber composite materials, which uses a compaction mechanism to compact the printed layer, thereby improving the manufacturing efficiency of the continuous fiber reinforced composite material and the fiber / resin interface bonding strength, and increasing the material fiber volume fraction, thereby realizing high-performance and efficient additive manufacturing of continuous fiber reinforced composite materials.

[0007] However, the above solutions all use FDM additive manufacturing machines, whose gantry system has a limited forming platform size and performs slicing and layer-by-layer manufacturing along a single direction. Therefore, the forming size is limited, it is difficult to directly form complex parts with cantilever structures, and the formed part surface has a typical step effect.

[0008] In order to meet the demand for rapid manufacturing of large-scale complex continuous fiber reinforced composite parts, the robot-assisted additive manufacturing technology that introduces multi-degree-of-freedom industrial robots into additive manufacturing equipment can realize multi-degree-of-freedom additive manufacturing, such as the utility model patent with announcement number CN210634127U. Compared with traditional additive manufacturing technology, it has the following advantages:

[0009] (1) It can realize conformal additive manufacturing in multiple planes or curved surfaces. Traditional three-axis additive manufacturing systems can only manufacture parts layer by layer in a single direction, which results in the formed parts having a step effect along the curved or inclined plane, requiring a lot of post-processing to improve the surface finish, and the strength of the parts along their slicing manufacturing direction is low. Robot-assisted additive manufacturing technology can control the relative relationship between the material deposition direction and the manufacturing platform direction by introducing additional degrees of freedom, thereby changing the direction of plane layer-by-layer manufacturing or layer-by-layer manufacturing along the curved surface according to the requirements of the part loading conditions to avoid the step effect.

[0010] (2) It can realize ultra-large-scale additive manufacturing. Traditional additive manufacturing equipment is not suitable for large-scale applications of forming large-sized parts due to its limited size and high installation cost. Multi-degree-of-freedom robots can make full use of the robot's workspace to manipulate tools through the movement of multiple joints. If a multi-degree-of-freedom robot is connected to a mobile base, the robot can move around to further expand the workspace and print larger-scale products.

[0011] However, there is no technical solution that can achieve interlaminar reinforcement of parts in the process of forming continuous fiber composites using robot-assisted additive manufacturing technology, and the mechanical properties of the prepared continuous fiber composites are low.

[0012] In summary, in order to promote the future development and application of CFRTPCs parts, it is urgent to develop a new additive manufacturing process that can not only improve the mechanical properties of parts but also expand the forming freedom and working space. Summary of the invention

[0013] In view of the above defects or improvement needs of the prior art, the present invention provides a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement, which aims to improve the bonding performance between layers of continuous fiber composite materials and realize high-performance additive manufacturing of large-sized complex parts.

[0014] To achieve the above-mentioned object, according to one aspect of the present invention, a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement is provided, comprising: a controller, a robot arm, a positioner and a printing unit; wherein the printing unit comprises a laser unit, a wire feeding unit and a pressure roller unit;

[0015] The wire feeding unit is connected to the end of the mechanical arm, and is used to feed out the continuous fiber composite filament and limit the fed part to the position below the pressure roller unit;

[0016] The laser unit is connected to the end of the mechanical arm and is used to heat the delivered continuous fiber composite filament to a semi-molten state with a temperature higher than the glass transition temperature of the resin and lower than its melting point by laser;

[0017] The pressing roller unit is connected to the end of the mechanical arm and is used to generate pressure to flatten the continuous fiber composite filaments that have not yet solidified after being heated by the laser beam into a strip shape;

[0018] The positioner is arranged below the robot arm, and a printing platform is rigidly connected to its surface, so as to receive the composite filaments formed by the printing unit at the end of the robot arm, and finally bond and stack them layer by layer into a high-density part;

[0019] The controller is used to control the rotational movement of each joint of the robot arm, the rotational movement of each joint of the positioner, the movement speed of the printing unit, the laser power of the laser unit and the pressure generated by the pressure roller unit; the combination of the rotational movement of each joint of the robot arm can enable the printing unit at the end of the robot arm to achieve six-degree-of-freedom movement; the combination of the rotational movement of each joint of the positioner can enable the printing platform to achieve multi-degree-of-freedom movement; the movement speed of the printing unit is matched with the laser power.

[0020] Furthermore, the system also includes a sacrificial mold; the path of the printing unit follows the surface contour of the sacrificial mold, which is used to form complex curved surface parts.

[0021] Furthermore, the pressure roller unit is provided with a freely rotating roller, and during the forming process, the surface of the roller is always parallel to the surface of the printing platform, the surface of the sacrificial mold or the surface of the formed part.

[0022] Furthermore, the system also includes an air supply pipe; the air supply pipe is used to provide protective gas to the vicinity of the wire feeding unit, and when the continuous fiber composite filament is heated by the laser unit, the protective gas suppresses its combustion.

[0023] Furthermore, the protective gas is nitrogen.

[0024] Furthermore, the system also includes a filament storage tray for storing continuous fiber composite filament raw materials.

[0025] The present invention also provides a forming method of a robot-assisted laser additive manufacturing system based on the above-mentioned continuous fiber composite interlayer reinforcement, comprising:

[0026] S1. Adaptively slice the 3D digital model of the part into multiple layers, then generate the printing path information of each slice layer according to the optimal filling strategy and export the text file that can be read by the manufacturing system, and then transmit it to the robot arm and positioner to make them move in coordination;

[0027] S2. The manufacturing system drives the end wire feeding unit and the pressure roller unit to move in space through the robotic arm. At the same time, the controller accurately controls the movement speed of the printing unit, the laser power of the laser unit and the pressure generated by the pressure roller unit. The laser beam generated by the laser unit is used to heat the continuous fiber composite filament to make it reach a semi-molten state and is flattened into a strip under the action of the pressure roller unit.

[0028] S3. As the printing unit moves, the bonded composite filaments exert traction on the unmelted wire, causing it to be continuously fed out from the wire storage tray through the wire feeding unit. The surfaces of the printing platform, sacrificial mold and parts can all be used to receive the composite filaments formed by the printing unit at the end of the robotic arm, and finally bonded and stacked layer by layer into a high-density part.

[0029] In general, compared with the prior art, the above technical solution conceived by the present invention can achieve the following beneficial effects.

[0030] The pressure generated by the pressing roller unit in the manufacturing system of the present invention can flatten the composite filaments heated by the laser beam into a strip shape. The thermoplastic resin that has not yet solidified after being heated by the laser beam can penetrate into the pores between the layers under the pressure of the pressing roller unit, and evenly wrap the continuous fibers, thereby improving the interlayer bonding performance and density of the composite material, so that when the formed parts are subjected to stress, the stress can be effectively transferred to the continuous fibers through the resin matrix, thereby exhibiting higher mechanical properties.

[0031] The printing path information generated by the controller in the manufacturing system of the present invention does not need to be planar sliced ​​and stacked in the Z direction like traditional FDM printing. Its path information can form a three-dimensional surface and can be stacked in any direction; the introduced robot-assisted additive manufacturing system expands the freedom and workspace of the printing unit. The printing unit is driven by the robot arm and the coordinated movement of the positioner and can be formed at any position in the workspace; the composite wire is not flattened before deposition, and is a cylinder with a diameter of 0.2mm to 1.0mm. Compared with strip materials, it can easily form higher-precision corners and complex paths. The combined effect of the above gain effects enables the forming method to realize additive manufacturing of large-sized complex parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic structural diagram of a robot-assisted laser additive manufacturing system for interlayer reinforcement of continuous fiber composites constructed according to a preferred embodiment of the present invention;

[0033] Figure 2 It is a schematic diagram of the structure of the printing unit at the end of the robotic arm;

[0034] Figure 3 It is a schematic diagram of the coordinate system of the robot-assisted laser additive manufacturing system;

[0035] Figure 4 It is a schematic diagram of the forming process principle of the robot-assisted laser additive manufacturing system for interlayer reinforcement of continuous fiber composites. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] Reference Figure 1 , a robot-assisted laser additive manufacturing system for interlayer reinforcement of continuous fiber composite 6 materials, including a manufacturing system 101 and a controller 102.

[0038] The manufacturing system 101 includes a robot arm 110, a positioner 120, a printing unit 130, a wire storage tray 140, and a system coordinate system.

[0039] The robotic arm 110 is preferably a six-axis or seven-axis robotic arm, and is further preferably a six-axis robotic arm, with a printing unit 130 installed at its end; further, the robotic arm 110 can control the rotational movement of each joint by a control signal transmitted by the controller 102, and the combination of the rotational movements of each joint can make the printing unit 130 at the end of the robotic arm 110 move at any speed with reference to the robotic arm base coordinate system 201 in the following forms: ±X direction, ±Y direction, ±Z direction, ±θx direction of rotation around the X-axis, ±θy direction of rotation around the Y-axis, ±θz direction of rotation around the Z-axis, and any combination of the above.

[0040] The positioner 120 is arranged below the robot 110, and is preferably a two-degree-of-freedom or three-degree-of-freedom positioner, and is further preferably a two-degree-of-freedom positioner, whose surface is provided with a printing platform 121, and the printing unit 130 at the end of the robot 110 forms a part 123 on the surface of the printing platform 121 or the sacrificial mold 122; further, the positioner 120 can control the rotation movement of each joint by the control signal transmitted by the controller 102, and the combination of the rotation movement of each joint can make the printing platform 121 and the sacrificial mold 122 on the surface of the positioner 120 move at any speed with reference to the positioner origin coordinate system 202 in the following forms: ±θz direction of rotation around the Z axis; ±θy direction of rotation around the Y axis; according to the needs of specific applications, keep synchronized with the movement speed of the printing unit 130 at the end of the robot 110 or keep it stationary and at any angle.

[0041] The printing platform 121 is rigidly connected to the upper surface of the positioner 120, and a sacrificial mold 122 is fixed thereon. The surfaces of the printing platform 121, the sacrificial mold 122 and the part 123 can all be used to receive the composite filament 141 formed by the printing unit 130 at the end of the robot 110, and finally bond and stack them layer by layer into a high-density part 123; the printing platform 121 and the positioner 120 cannot have relative movement, and are preferably an aluminum alloy plate.

[0042] Reference Figure 2 The printing unit 130 includes a laser unit 131 , a wire feeding unit 132 , and a pressure roller unit 133 .

[0043] The laser unit 131 is hinged to the robot arm 110, and its laser emitting end is arranged at the discharge end of the composite filament 141 relative to the gap of the wire feeding unit 132. The power of the laser unit 131 is adjusted by the controller 102, and its laser power is precisely matched with the movement speed of the printing unit, so as to heat the composite filament 141 by laser to a semi-molten state higher than the glass transition temperature of the resin and lower than its melting point.

[0044] The wire feeding unit 132 is connected to the robot arm 110, and can limit the exposed portion of the composite filament 141 to a position below the pressure roller unit 133. As the printing unit 130 moves, the bonded composite filament 141 generates a pulling force on the unmelted wire material, so that the wire material is continuously fed out from the wire storage tray 140 through the wire feeding unit 132.

[0045] The pressure roller unit 133 is connected to the robot arm 110 and includes a freely rotatable roller. According to the printing path requirements, the surface of the roller is always parallel to the surface of the printing platform 121, the surface of the sacrificial mold 122 or the surface of the part 123 during the forming process. The pressure of the pressure roller unit 133 is adjusted by the controller 102. The generated pressure can flatten the composite filament 141 that has not yet solidified after being heated by the laser beam into a strip.

[0046] The air supply pipe 134 provides a predetermined shielding gas from a gas source to the vicinity of the wire feeding unit 132, and the shielding gas can replace oxygen in a local range, and when the composite filament 141 is heated by the laser unit 131, the shielding gas inhibits its combustion. Further preferably, the shielding gas in the air supply pipe 134 is nitrogen.

[0047] The wire storage tray 140 can store composite filaments 141 of limited length. The composite filaments 141 are continuous fiber composite wires, composed of reinforcements and a matrix, and have a cross-section of a circle with a diameter of 0.2 mm to 1.0 mm, including but not limited to cylindrical composite wires of continuous carbon fibers impregnated with thermoplastic resins. Further, the reinforcements in the composite filaments 141 are continuous fibers, which can be one or more of glass fibers, aramid fibers, carbon fibers, carbon nanotube fibers, and ceramic fibers. The number of continuous fibers can be between 1K and 16K (each wire contains 1000 to 16000 continuous carbon fiber filaments). The matrix of the composite filaments 141 can be one or more of thermoplastic resins such as PA, PLA, ABS, PET, PETG, and PEEK, or can be thermosetting resins, cement, metals, or ceramics.

[0048] refer to Figure 3 The system coordinate system includes a robot base coordinate system 201, a positioner origin coordinate system 202, and a robot end coordinate system 203; the robot base coordinate system 201 is a reference coordinate system of the manufacturing system 101, the positioner origin coordinate system 202 is a coordinate system determined according to the intersection of the rotation axes of the positioner 120, and the robot end coordinate system 203 is a coordinate system established according to a certain point near the end of the pressure roller unit 133 in the printing unit 130; when placing the robot 110 and the positioner 120, the X coordinate system of the robot base coordinate system 201 is The plane formed by the A and Y axes must be parallel to the plane formed by the X and Y axes of the positioner origin coordinate system 202; at the initial moment of printing, the positioner origin coordinate system 202 and the robot arm end coordinate system 203 must ensure that they are in the set initial relative positions; further, at the initial moment of printing, the relative posture relationship between the robot arm base coordinate system 201, the positioner origin coordinate system 202, and the robot arm end coordinate system 203 is known, and the relative posture of the sacrificial mold 122 and the positioner origin coordinate system 202 is fixed and known.

[0049] The controller 102 includes the hardware and software required to control the robot arm 110, the positioner 120 and the laser unit 131, the wire feeding unit 132 and the pressure roller unit 133 in the printing unit 130 at the end of the robot arm 110 in the manufacturing system 101, so as to manufacture the part 123; the controller 102 can accurately control the movement speed of the printing unit 130, the laser power of the laser unit 131 and the pressure generated by the pressure roller unit; the controller 101 includes computer-aided design / computer-aided manufacturing (CAD / CAM) functions to complete model design, layered slicing, path planning, communication control, and simulation. Furthermore, the printing path information generated by the controller 102 does not need to be planar sliced ​​and stacked in the Z direction like traditional FDM printing. Its path information can form a three-dimensional surface and can be stacked in any direction.

[0050] Reference Figure 4 , a robot-assisted laser additive manufacturing method for interlaminar reinforcement of continuous fiber composite materials, the steps are as follows:

[0051] (1) The controller 102 adaptively slices the three-dimensional digital model of the part (such as an STL model file) into multiple layers, and then generates printing path information for each slice layer according to the optimal filling strategy and exports a text file that can be read by the manufacturing system 101, and then transmits it to the robot arm 110 and the positioner 120 to enable coordinated movement;

[0052] (2) The manufacturing system 101 drives the terminal continuous fiber feeding unit 132 and the pressing roller unit 133 to move in space through the robot arm 110. The controller 102 accurately controls the movement speed of the printing unit 130, the laser power of the laser unit 131, and the pressure generated by the pressing roller unit 133. The laser beam generated by the laser unit 131 is used to heat the composite filament 141 to make it reach a semi-molten state and be flattened into a strip under the action of the pressing roller unit 133. As the printing unit 130 moves, the bonded composite filament 141 generates traction on the unmelted wire material, so that it is continuously fed out of the wire storage disk 140. The surfaces of the printing platform 121, the sacrificial mold 122, and the part 123 can all be used to receive the composite filament 141 formed by the printing unit 130 at the end of the robot arm 110, and finally bond and stack them layer by layer to form a high-density part 123.

[0053] In the forming method, the thermoplastic resin that has not yet solidified after being heated by the laser beam can penetrate into the pores between the layers under the pressure of the pressure roller unit 133, and evenly wrap the continuous fibers, thereby improving the interlayer bonding performance and density of the composite material, so that when the formed part is subjected to stress, the stress can be effectively transferred to the continuous fibers through the resin matrix, showing higher mechanical properties; the printing path information generated by the controller does not need to be planar sliced ​​and stacked in the Z direction like traditional FDM printing, and its path information can form a three-dimensional surface and can be stacked in any direction; the introduced robot-assisted additive manufacturing system expands the freedom and workspace of the printing unit, and the printing unit 130 is driven by the robot arm 110 and the coordinated movement of the positioner 120 and can be formed at any position in the workspace; the composite wire material 141 is not flattened before deposition, and is a cylinder with a diameter of 0.2mm to 1.0mm. Compared with the strip material, it can easily form a higher precision corner and a complex path. The combined influence of the above effects enables the forming method to achieve both interlayer reinforcement of continuous fiber composite materials and high-performance additive manufacturing of large-sized complex parts.

[0054] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A forming method of a robot-assisted laser additive manufacturing system for interlayer reinforcement of continuous fiber composites, characterized in that: The system includes: a controller, a robot arm, a positioner and a printing unit; wherein the printing unit includes a laser unit, a wire feeding unit and a pressure roller unit; The wire feeding unit is connected to the end of the mechanical arm, and is used to feed the continuous fiber composite filament, and limit the fed part to the position below the pressure roller unit; wherein the continuous fiber composite filament is composed of a reinforcement and a matrix, the reinforcement is a continuous fiber, and the matrix is ​​a thermoplastic resin; the continuous fiber composite filament is not flattened before deposition, and is a cylinder with a diameter of 0.2mm-1.0mm; The laser unit is connected to the end of the mechanical arm and is used to heat the delivered continuous fiber composite filament to a semi-molten state with a temperature higher than the glass transition temperature of the resin and lower than its melting point by laser; The pressing roller unit is connected to the end of the mechanical arm, and is used to generate pressure to flatten the continuous fiber composite filaments that have not yet solidified after being heated by the laser beam into a strip shape. The thermoplastic resin that has not yet solidified after being heated by the laser beam penetrates into the pores between the layers under the pressure of the pressing roller unit, and evenly wraps the continuous fibers, thereby improving the interlayer bonding performance and density of the composite material, so that when the formed part is subjected to stress, the stress is transmitted to the continuous fibers through the resin matrix, and has higher mechanical properties; The positioner is arranged below the robot arm, and a printing platform is rigidly connected to its surface, so as to receive the composite filaments formed by the printing unit at the end of the robot arm, and finally bond and stack them layer by layer into a high-density part; The controller is used to control the rotational movement of each joint of the robot arm, the rotational movement of each joint of the positioner, the movement speed of the printing unit, the laser power of the laser unit and the pressure generated by the pressure roller unit; the combination of the rotational movement of each joint of the robot arm can enable the printing unit at the end of the robot arm to achieve six degrees of freedom; the combination of the rotational movement of each joint of the positioner can enable the printing platform to achieve multi-degrees of freedom movement; the size of the movement speed of the printing unit matches the size of the laser power; Forming methods include: S1. Adaptively slice the 3D digital model of the part into multiple layers, generate the printing path information of each slice layer according to the optimal filling strategy, and export the text file that can be read by the manufacturing system, and then transmit it to the robot arm and positioner to make them move in coordination; S2. The manufacturing system drives the end wire feeding unit and the pressure roller unit to move in space through the robotic arm. At the same time, the controller accurately controls the movement speed of the printing unit, the laser power of the laser unit and the pressure generated by the pressure roller unit. The laser beam generated by the laser unit is used to heat the continuous fiber composite filament to make it reach a semi-molten state and is flattened into a strip under the action of the pressure roller unit. S3. As the printing unit moves, the bonded composite filaments exert traction on the unmelted wire, causing it to be continuously fed out from the wire storage tray through the wire feeding unit. The surfaces of the printing platform, sacrificial mold and parts can all be used to receive the composite filaments formed by the printing unit at the end of the robotic arm, and finally bonded and stacked layer by layer into a high-density part.

2. The forming method of a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement according to claim 1, characterized in that: The system also includes a sacrificial mold; the path of the printing unit follows the surface contour of the sacrificial mold, which is used to form complex curved surface parts.

3. The forming method of a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement according to claim 2, characterized in that: The pressure roller unit is provided with a freely rotating roller, and during the forming process, the surface of the roller is always parallel to the surface of the printing platform, the surface of the sacrificial mold or the surface of the formed part.

4. The forming method of a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement according to any one of claims 1 to 3, characterized in that: The system also includes an air supply pipe; the air supply pipe is used to provide a protective gas near the wire feeding unit, and when the continuous fiber composite filament is heated by the laser unit, the protective gas inhibits its combustion.

5. The forming method of a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement according to claim 4, characterized in that: The protective gas is nitrogen.

6. The forming method of a robot-assisted laser additive manufacturing system for continuous fiber composite interlayer reinforcement according to any one of claims 1 to 4, characterized in that: The system also includes a filament storage tray for storing continuous fiber composite filament raw materials.

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