Method and device for planning fiber placement track of complex curved surface

Abstract

The invention relates to the technical field of carbon fiber composite material forming and manufacturing, in particular to a fiber placement track planning method and device for a complex curved surface. The method comprises the steps that a laying curved surface is divided into a plurality of areas by arranging a plurality of guide lines; determining the guide line in each area as a current track, performing equidistant offset on the current track, determining a new track as the current track if the new track obtained after each equidistant offset meets a corresponding expected laying direction requirement, and otherwise, performing planning adjustment on the new track according to the expected laying direction; and in the equidistant offset process, stopping when reaching the boundary of the area or the next guide line, and finishing track planning of the workpiece to be subjected to wire placement according to all the obtained current tracks. The problems that an existing fiber placement track planning method cannot meet the track planning requirement when a strict angle requirement exists or a curved surface is complex, gap overlapping is likely to be too large, machining wrinkles are likely to occur, and the deviation between the gap overlapping and the preset angle is large are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon fiber composite material molding and manufacturing, and in particular to a method and device for planning fiber laying trajectory for a complex curved surface. Background Art

[0002] Carbon fiber placement is a process in which continuous fibers are laid down in specific paths and angles and then cured, usually with resin, to form a composite material. This process enables the manufacture of parts with complex shapes and excellent strength and stiffness.

[0003] Trajectory planning technology is a key technology for carbon fiber placement. Its main function is to generate a placement trajectory according to the designed placement direction, while minimizing overlaps, gaps, wrinkles and other defects. At present, for simple components, algorithms such as fully fixed angles and equidistant offsets are often used. However, on irregular surfaces or surfaces with special angle requirements, these algorithms often produce shortcomings such as excessive gap overlaps, processing wrinkles, and large deviations from the predetermined angle, which cannot meet the requirements.

[0004] The existing laying trajectory planning method cannot completely solve the trajectory planning problem when there are strict angle requirements or when the surface is more complex. For example, projection is required when planning the laying trajectory, but many surfaces (such as rotational surfaces) cannot be projected, and its specific planning method still uses the traditional fixed angle or geodesic algorithm; at the same time, its dense laying method only uses the method of changing the bandwidth, and does not use the dynamic increase or decrease of laying, which cannot meet the requirements when the surface angle requirements are complex. Summary of the invention

[0005] The present invention proposes a fiber placement trajectory planning method and device for complex curved surfaces to solve the problem that the existing fiber placement trajectory planning method cannot meet the trajectory planning requirements when there are strict angle requirements or the curved surface is relatively complex, and is prone to problems such as excessive gap overlap, processing wrinkles, and large deviations from the predetermined angle.

[0006] According to one aspect of the present invention, a method for planning a fiber placement trajectory on a complex curved surface is provided, comprising:

[0007] Acquire a three-dimensional curved surface model of a workpiece to be wire laid, and divide the laying curved surface of the three-dimensional curved surface model into a plurality of regions by setting a plurality of guide lines;

[0008] Determine the guide line in each area as the current trajectory, perform equidistant offset on the current trajectory, and determine whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements. If so, determine the new trajectory as the current trajectory; otherwise, plan and adjust the new trajectory according to the expected laying direction, and determine the adjusted new trajectory as the current trajectory;

[0009] During the equidistant offset process, the process stops when reaching the boundary of the area or the next guide line, and the trajectory planning of the workpiece to be wire laid is completed based on all the current trajectories obtained.

[0010] Preferably, a closed curve for marking a laying area and / or a window opening area is set on the laying surface of the acquired three-dimensional surface model;

[0011] Wherein, the boundary is: a closed curve of the laying area.

[0012] Preferably, the method of dividing the laying surface of the three-dimensional curved surface model into a plurality of regions by setting a plurality of guide lines comprises:

[0013] Each of the regions is adjacent to at most two of the guide lines and at least one of the guide lines, and there is no intersection between the guide lines.

[0014] Preferably, the method for judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirement includes:

[0015] Determine whether the workpiece to be laid has a certain axis. If yes, the projection of the axis direction at any point on the new trajectory is the desired laying direction corresponding to the new trajectory.

[0016] If not, the expected laying direction corresponding to the new trajectory is determined according to the guide lines in the area.

[0017] Preferably, the method for determining the desired laying direction corresponding to the new trajectory according to the guide line in the area includes:

[0018] If the area is adjacent to a guide line, then:

[0019] Determine the point P2 on the guide line corresponding to the point P1 on the new trajectory when the distance to the guide line is the shortest;

[0020] Determine the tangent direction V1 at point P2;

[0021] Determine the tangent plane S of the laid surface at point P1;

[0022] V2 obtained by projecting V1 onto S is the desired laying direction of point P1.

[0023] Preferably, the method for determining the desired laying direction corresponding to the new trajectory according to the guide line in the area includes:

[0024] If the region is adjacent to two guide lines, then:

[0025] Determine the points P2 and P3 on the guide lines corresponding to when any point P1 on the new trajectory reaches the closest point between the two guide lines;

[0026] Determine the tangent directions V1 and V2 at points P2 and P3;

[0027] According to V1 and V2, determine the weighted direction V3 of the two guide line directions;

[0028] Project V3 to S to obtain the desired laying direction V4 of point P1;

[0029] and / or,

[0030] The method for determining the weighted direction V3 of the directions of the two guide lines according to V1 and V2 includes:

[0031] The weighted direction V3=d2*V1+d1*V2;

[0032] Where: d1 is the distance from P2 to P1, d2 is the distance from P3 to P1.

[0033] Preferably, the method for judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirement includes:

[0034] It is determined whether the angle between the new trajectory and the corresponding expected laying direction of the area does not exceed a predetermined value. If so, the new trajectory meets the corresponding expected laying direction requirement; otherwise, the new trajectory does not meet the corresponding expected laying direction requirement.

[0035] Preferably, the method for planning and adjusting the new trajectory according to the desired laying direction includes:

[0036] The direction of the new track is adjusted to the corresponding desired laying direction, and the distance between the new track and the previous current track is adjusted to minimize the overlap rate and gap rate between the two.

[0037] Preferably, the method for completing trajectory planning of a workpiece to be wire laid according to all current trajectories obtained comprises:

[0038] The obtained current trajectory is divided into a laying area trajectory and a non-laying area trajectory by using the closed curve;

[0039] The segmented current trajectory is discretized into trajectory points, and numerical control machining codes are generated according to the trajectory points.

[0040] According to one aspect of the present invention, a fiber placement trajectory planning device for a complex curved surface is provided, comprising:

[0041] A region segmentation unit is used to obtain a three-dimensional surface model of a workpiece to be wire laid, and to segment a laying surface of the three-dimensional surface model into a plurality of regions by setting a plurality of guide lines;

[0042] A trajectory determination unit is used to determine the guide line in each area as the current trajectory, perform equidistant offset on the current trajectory, and determine whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements. If so, the new trajectory is determined to be the current trajectory; otherwise, the new trajectory is planned and adjusted according to the expected laying direction, and the adjusted new trajectory is determined to be the current trajectory;

[0043] The trajectory planning unit is used to stop when reaching the boundary of the area or the next guide line during the equidistant offset process, and complete the trajectory planning of the workpiece to be wired based on all the current trajectories obtained.

[0044] The present invention has at least the following beneficial effects:

[0045] The present invention proposes a fiber placement trajectory planning method and device for complex curved surfaces, which divides the area by setting guide lines, plans a trajectory with an angle consistent with the guide line at the guide line, and fully lays the fiber in the area divided by the guide line by adding or reducing wires while meeting the angle requirements. This allows the design of the laying angle to have a high degree of freedom, allows the planned trajectory to meet the design angle as much as possible, and controls the gap and overlap within a smaller range. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present invention and, together with the specification, are used to explain the technical solutions of the present invention.

[0047] Figure 1 A flowchart showing a method for planning a fiber placement trajectory for a complex curved surface according to an embodiment of the present invention is shown;

[0048] Figure 2 A schematic diagram of guide lines on a wire laying curved surface according to an embodiment of the present invention is shown;

[0049] Figure 3 A schematic diagram of a fiber placement curved surface segmentation area according to an embodiment of the present invention is shown;

[0050] Figure 4 A schematic diagram showing a desired laying direction according to an embodiment of the present invention is shown;

[0051] Figure 5 A schematic diagram of a laying trajectory according to an embodiment of the present invention is shown;

[0052] Figure 6 A schematic diagram showing a non-laying trajectory line of a non-laying area according to an embodiment of the present invention;

[0053] Figure 7 A flow chart showing a method for determining a laying trajectory according to an embodiment of the present invention is shown;

[0054] Figure 8 A diagram showing a flat surface model according to an embodiment of the present invention is shown;

[0055] Fig. 9 A diagram showing the results of wire laying trajectory planning for a flat surface model according to an embodiment of the present invention is shown;

[0056] Fig.10 The embodiment according to the present invention is shown Fig. 9 A partial enlarged view of

[0057] Fig.11 A C-beam curved surface model diagram according to an embodiment of the present invention is shown;

[0058] Fig.12 A diagram showing the wire laying trajectory planning result of a C-beam curved surface model according to an embodiment of the present invention is shown;

[0059] Fig.13 The embodiment according to the present invention is shown Fig.12 A partial enlarged view of . DETAILED DESCRIPTION

[0060] Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0061] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0062] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0063] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0064] Figure 1 Flowchart of the fiber placement trajectory planning method for complex curved surfaces; Figure 2 It is a schematic diagram of the guide line on the wire laying surface; Figure 3 It is a schematic diagram of the segmentation area of ​​the wire laying surface; Figure 4 A schematic diagram of the desired laying direction;

[0065] Figure 5 This is a schematic diagram of laying the trajectory line; Figure 6 It is a schematic diagram of non-laying trajectory lines in the non-laying area; Figure 7 A flow chart of a method for determining a laying trajectory line; Figure 8 This is a flat surface model diagram; Fig. 9 The wire laying trajectory planning result diagram for flat surface models; Fig.10 for Fig. 9 A partial enlarged view of Fig.11 This is the C-beam surface model diagram; Fig.12 This is the result diagram of wire laying trajectory planning for the C-beam surface model; Fig.13 for Fig.12 A partial enlarged view of the Figure 1-13 As shown, a fiber placement trajectory planning method for a complex surface includes: step S01: obtaining a three-dimensional surface model of a workpiece to be placed, and dividing the placement surface of the three-dimensional surface model into a plurality of regions by setting a plurality of guide lines; step S02: determining the guide line in each region as the current trajectory, equidistantly offsetting the current trajectory, and judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected placement direction requirement, if so, determining the new trajectory as the current trajectory, otherwise, planning and adjusting the new trajectory according to the expected placement direction, and determining the adjusted new trajectory as the current trajectory; step S03: in the equidistant offset process, stopping when reaching the boundary of the region or the next guide line, and completing the trajectory planning of the workpiece to be placed according to all the current trajectories obtained.

[0066] The method for planning fiber placement trajectories on a complex curved surface provided by an embodiment of the present invention specifically includes the following steps:

[0067] Step S01: obtaining a three-dimensional surface model of a workpiece to be wire laid, and dividing the laying surface of the three-dimensional surface model into a plurality of regions by setting a plurality of guide lines.

[0068] In an embodiment of the present invention, the acquired three-dimensional curved surface model of the workpiece to be wire laid includes a laying surface, and the laying surface can be a plane, a curved surface, a combined curved surface or a special-shaped revolved surface.

[0069] In the present invention, a closed curve for marking a laying area and / or a window opening area is set on the laying surface of the acquired three-dimensional surface model; wherein the boundary is: a closed curve of the laying area.

[0070] In an embodiment of the present invention, a laying boundary composed of closed curves is set on the laying surface of the three-dimensional surface model for marking the laying area. A window boundary composed of closed curves can also be set for marking the window area, that is, the area where no wire laying is performed.

[0071] On the laying surface of the 3D surface model, one or more penetrating guide lines are set at the same time to serve as laying angle references.

[0072] In the present invention, the method of dividing the laying surface of the three-dimensional surface model into several areas by setting several guide lines includes: each of the areas is adjacent to at most two of the guide lines and at least one of the guide lines, and there is no intersection between the guide lines.

[0073] In the embodiment of the present invention, the laying surface is divided into multiple areas by setting guide lines, and each area is adjacent to at most two guide lines and at least one guide line. If there are edges on the three-dimensional surface model of the workpiece to be laid, it is necessary to set guide lines along the edges according to the required laying direction or force direction.

[0074] like Figure 2 As shown, a laying boundary 2 and a laying window boundary 3 , as well as a first guide line 4 and a second guide line 5 are set on the laying surface 1 .

[0075] like Figure 3 As shown, the first guide line and the second guide line divide the laying surface 1 into three independent areas, namely area 1, area 2 and area 3. Area 1 is adjacent to the first guide line 4, area 2 is adjacent to the first guide line 4 and the second guide line 5, and area 3 is adjacent to the second guide line 5.

[0076] Step S02: Determine the guide line in each area as the current trajectory, perform equidistant offset on the current trajectory, and determine whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements. If so, determine the new trajectory as the current trajectory; otherwise, plan and adjust the new trajectory according to the expected laying direction, and determine the adjusted new trajectory as the current trajectory.

[0077] In the present invention, the method for judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements includes: judging whether the workpiece to be laid has a certain axis. If so, the projection of the axis direction at any point on the new trajectory is the expected laying direction corresponding to the new trajectory; if not, the expected laying direction corresponding to the new trajectory is determined according to the guide lines in the area.

[0078] In the embodiment of the present invention, the desired laying direction of any point in each area can be determined by a variety of methods, such as an axis or a guide line.

[0079] When the direction field is established with an axis, the expected laying direction of any point on the new trajectory in the area is the projection of the axis direction of the surface of the workpiece to be laid at that point.

[0080] When the direction field is established with guide lines, the expected placement direction of any point on the new trajectory in the area is determined by the direction of the adjacent guide lines and the distance from the point to the guide lines. The shorter the distance between the point and the guide lines, the greater the influence of the guide lines on the placement direction.

[0081] In the present invention, the method for determining the expected laying direction corresponding to the new trajectory based on the guide line in the area includes: if the area is adjacent to a guide line, then: determining the point P2 on the guide line corresponding to any point P1 on the new trajectory when the distance to the guide line is shortest; determining the tangent direction V1 at point P2; determining the tangent plane S of the laying surface at point P1; and V2 obtained by projecting V1 onto S is the expected laying direction of point P1.

[0082] In the embodiment of the present invention, when the direction field is established by the guide line, if there is only one guide line in the area, such as Figure 3 As shown in regions 1 and 3 in FIG, a new trajectory g in the region is determined by a single guide line. now The expected laying direction of any point on the surface, if there are two guide lines in the area, such as Figure 3 As shown in area 2, the new trajectory g in the area is determined by two guide lines. now The desired laying direction at any point on the

[0083] Among them, the method of determining the desired laying direction by a single guide line is:

[0084] Determine the new trajectory g in the area now For any point P1 on the surface, find the point P2 closest to P1 on the guide line of the area;

[0085] Determine the tangent direction V1 of the guide line at point P2;

[0086] Determine the tangent plane S of the laid surface at point P1;

[0087] Project V1 to S to get V2, then V2 is point P1, that is, the new trajectory g now The corresponding expected laying direction.

[0088] In the present invention, the method for determining the expected laying direction corresponding to the new trajectory according to the guide lines in the area includes: if the area is adjacent to two guide lines, then: determining the points P2 and P3 on the guide lines corresponding to the point P1 on the new trajectory when the distance between the two guide lines is the shortest; determining the tangent directions V1 and V2 at the points P2 and P3; determining the weighted direction V3 of the directions of the two guide lines according to V1 and V2; projecting V3 to S to obtain the expected laying direction V4 of the point P1; and / or, the method for determining the weighted direction V3 of the directions of the two guide lines according to V1 and V2 includes:

[0089] The weighted direction V3 = d2*V1 + d1*V2 (1);

[0090] Where: d1 is the distance from P2 to P1, d2 is the distance from P3 to P1.

[0091] In an embodiment of the present invention, the method for determining the laying direction by two guide lines is:

[0092] Determine the new trajectory g in the area now For any point P1 on the surface, find the points P2 and P3 closest to P1 on the two guide lines in the area, as well as the distances d1 and d2 between P1, P2 and P3;

[0093] Determine the tangent directions V1 and V2 of the guide line at points P2 and P3;

[0094] Determine the tangent plane S of the laid surface at point P1;

[0095] According to the tangent directions V1 and V2, the weighted direction V3 of the two guide line directions is determined using formula (1);

[0096] Project the weighted direction V3 onto the tangent plane S to obtain V4, then V4 is point P1, that is, the new trajectory g now The corresponding expected laying direction.

[0097] like Figure 4 As shown, the desired laying angle field of each area based on the first guide line 4 and the second guide line 5 is shown. Figure 4 6, 7, and 8 are the new trajectories g in the three segmented areas. now Any point on .

[0098] Among them, the area where point 6 is located is only adjacent to the first guide line 4, so its expected angle (expected laying direction) is determined by the first guide line 4. Similarly, the area where point 8 is located is only adjacent to the second guide line 5, so its expected angle is determined by the second guide line 5; the area where point 7 is located is adjacent to the first guide line 4 and the second guide line 5, so its expected angle is determined by both guide lines.

[0099] In the present invention, a method for determining whether a new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirement includes: determining whether an angle between the new trajectory and the corresponding expected laying direction of the area does not exceed a predetermined value; if so, the new trajectory meets the corresponding expected laying direction requirement; otherwise, the new trajectory does not meet the corresponding expected laying direction requirement.

[0100] In the embodiment of the present invention, Figure 7 As shown in FIG. 1 , it is a flowchart for determining the current track in each area. The method for determining the current track in each area, that is, the specific process of step S02 is as follows:

[0101] Step S02.1: Generate a guide line trajectory g1 in the area strictly according to the direction of the guide line; if there are two guide lines, generate two guide line trajectories g1 and g2; use the guide line trajectory g1 or g1 and g2 as the current trajectory g current ;

[0102] Step S02.2: For the current trajectory g current Perform equidistant offset, the direction of the equidistant offset is the direction away from the guide line in the area, and the new trajectory g is obtained after equidistant offset now ;

[0103] Step S02.3: Determine the new trajectory g now Whether the matching degree between the new trajectory g and the corresponding expected laying direction meets the predetermined requirements, if yes, then the new trajectory g is determined. now is the current trajectory g current , otherwise, for the new trajectory g now Re-plan and adjust the expected laying direction of the area to determine the adjusted new trajectory g now is the current trajectory g current .

[0104] The preset value ranges from 5 to 10 degrees.

[0105] In the present invention, the method for planning and adjusting the new trajectory according to the expected laying direction includes: adjusting the direction of the new trajectory to the corresponding expected laying direction, and adjusting the distance between the new trajectory and its previous current trajectory to minimize the overlap rate and gap rate between the two.

[0106] In the embodiment of the present invention, the new trajectory g now The direction is adjusted to the corresponding desired laying direction, and the new trajectory g is adjusted at the same time now Its previous current trajectory g current , that is, the spacing between the current tracks before the equidistant offset, so that the gap between the two is minimized under the set overlap rate.

[0107] Step S03: During the equidistant offset process, the process stops when reaching the boundary of the area or the next guide line, and completes the trajectory planning of the workpiece to be wire laid based on all the current trajectories obtained.

[0108] In the present invention, the method for completing the trajectory planning of the workpiece to be wire-laid based on all the current trajectories obtained includes: dividing the current trajectory obtained into a laying area trajectory and a non-laying area trajectory using the closed curve; discretizing the divided current trajectory into trajectory points, and generating CNC machining codes based on the trajectory points.

[0109] In the embodiment of the present invention, step S03.1: repeating steps S02.2 to S02.3 until reaching the laying area boundary of the area or reaching the next guide line, then all current trajectories g current Lay out track lines for the area.

[0110] Step S03.2: Repeat steps S02.1 to S03.1 to obtain the laying trajectory lines of all areas.

[0111] like Figure 5 As shown, in Figure 5 9 and 10 are two new trajectories g1 and g2 generated from the first guide line 4 and the second guide line 5, and then offset by equal distance. now , the new trajectory is the two laying trajectory lines.

[0112] After all the laying trajectory lines are obtained, the laying trajectory lines are divided into laying area trajectories and non-laying area trajectories according to the laying area and window area boundaries marked by closed curves. Figure 6 As shown, a planned laying trajectory line is shown, which is divided into a laying trajectory line 12 and a non-laying trajectory line 11 by the boundary of the laying area and the window area.

[0113] Each laying trajectory line is discretized into trajectory points, and the NC machining code is generated based on them.

[0114] like Figure 8As shown, a flat-plate model surface input, the dotted line is a closed laying boundary line, and the two solid lines are penetrating guide lines; according to the present invention, firstly, the two guide lines will divide the model surface into three areas, and then the wire laying trajectory planning is performed for the three areas respectively. During the planning process, the expected laying direction field of any point of the new trajectory in the three areas is determined. If the two boundary areas are adjacent to only one guide line, their expected direction is the same as the adjacent guide line. The middle area is adjacent to two guide lines, and its expected direction is the weighted direction of the two guide lines. After planning, the trajectory is cut with the laying boundary line to determine whether the trajectory is within the laying area. Finally, the processing code is generated based on the laying trajectory. Fig. 9 and 10 The results after trajectory planning are shown; Fig.10 In Figure a, Fig. 9 The middle part is enlarged, and Figure b is Fig. 9 From the enlarged view of the edge part, we can see that the guide line is completely consistent with the expected angle. The middle area automatically increases or decreases the yarn while ensuring the full laying angle and well controlling the overlap and gap.

[0115] Fig.11 The model surface of a C-beam is input, which includes a closed placement boundary line and two penetrating guide lines. The two guide lines divide the model surface into three areas, and the wire laying trajectory is planned for each of the three areas. After planning, the trajectory is cut with the placement boundary line to determine whether the trajectory is within the placement area. Finally, the processing code is generated based on the placement trajectory. Fig.12 and 13 To demonstrate the results after trajectory planning, the ability of the method of the present invention to plan trajectories for combined surfaces is demonstrated. It can be seen that the guide line is completely consistent with the expected angle. The middle area is fully laid out by automatically increasing or decreasing the yarn, while ensuring the laying angle and having good control over overlaps and gaps.

[0116] It can be understood that the above-mentioned various method embodiments mentioned in the present invention can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present invention will not go into details.

[0117] The execution subject of the fiber placement trajectory planning method for a complex curved surface may be a fiber placement trajectory planning device for a complex curved surface. For example, the fiber placement trajectory planning method for a complex curved surface may be executed by a terminal device or a server or other processing device, wherein the terminal device may be a user equipment (UE), a mobile device, a user terminal, a terminal, a cellular phone, a cordless phone, a personal digital assistant (PDA), a handheld device, a computing device, a vehicle-mounted device, a wearable device, etc. In some possible implementations, the fiber placement trajectory planning method for a complex curved surface may be implemented by a processor calling a computer-readable instruction stored in a memory.

[0118] Those skilled in the art will appreciate that, in the above method of specific implementation, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of the steps should be determined by their functions and possible internal logic.

[0119] In the present invention, a fiber placement trajectory planning device for complex surfaces is also proposed, including: a region segmentation unit, used to obtain a three-dimensional surface model of a workpiece to be placed, and divide the placement surface of the three-dimensional surface model into a plurality of regions by setting a plurality of guide lines; a trajectory line determination unit, used to determine the guide line in each region as the current trajectory, equidistantly offset the current trajectory, and judge whether the new trajectory obtained after each equidistant offset meets the corresponding expected placement direction requirement, if so, determine the new trajectory as the current trajectory, otherwise, plan and adjust the new trajectory according to the expected placement direction, and determine the adjusted new trajectory as the current trajectory; a trajectory planning unit, used to stop when reaching the boundary of the region or the next guide line during the equidistant offset process, and complete the trajectory planning of the workpiece to be placed according to all the current trajectories obtained.

[0120] In some embodiments, the functions or modules and units included in the device provided by the embodiment of the present invention can be used to execute the method described in the above method embodiment. Its specific implementation can refer to the description of the above method embodiment. For the sake of brevity, it will not be repeated here.

[0121] Mechanical or process limitations usually impose multiple restrictions on the laying angle. The method of the present invention makes the design of the laying angle more flexible. Different angle references can be designed in different areas of the curved surface through multiple guide lines, which can ensure that the angle at the guide line strictly meets the angle reference. In the guide line area, by adding or reducing yarn (filament), the laying angle can be made close to the angle reference and less than the allowable deviation, which can effectively ensure that the laying angle meets the design intent and process limitations, thereby obtaining better mechanical properties and reducing processing defects.

[0122] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A fiber placement trajectory planning method for a complex curved surface, characterized in that: include: Acquire a three-dimensional curved surface model of a workpiece to be wire laid, and divide the laying curved surface of the three-dimensional curved surface model into a plurality of regions by setting a plurality of guide lines; Determine the guide line in each area as the current trajectory, perform equidistant offset on the current trajectory, and determine whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements. If so, determine the new trajectory as the current trajectory; otherwise, plan and adjust the new trajectory according to the expected laying direction, and determine the adjusted new trajectory as the current trajectory; During the equidistant offset process, the process stops when reaching the boundary of the area or the next guide line, and the trajectory planning of the workpiece to be wire laid is completed based on all the current trajectories obtained.

2. The method for planning fiber placement trajectory on a complex curved surface according to claim 1, characterized in that: A closed curve for marking a laying area and / or a window opening area is set on the laying surface of the acquired three-dimensional surface model; Wherein, the boundary is: a closed curve of the laying area.

3. The method for planning fiber placement trajectory on a complex curved surface according to claim 1, characterized in that: The method of dividing the laying surface of the three-dimensional curved surface model into a plurality of regions by setting a plurality of guide lines comprises: Each of the regions is adjacent to at most two of the guide lines and at least one of the guide lines, and there is no intersection between the guide lines.

4. The method for planning fiber placement trajectory on a complex curved surface according to claim 1, characterized in that: The method for judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirement includes: Determine whether the workpiece to be laid has a certain axis. If yes, the projection of the axis direction at any point on the new trajectory is the desired laying direction corresponding to the new trajectory. If not, the expected laying direction corresponding to the new trajectory is determined according to the guide lines in the area.

5. The method for planning fiber placement trajectory for complex curved surfaces according to claim 4, characterized in that: The method for determining the expected laying direction corresponding to the new trajectory according to the guide line in the area includes: If the area is adjacent to a guide line, then: Determine the point P2 on the guide line corresponding to the point P1 on the new trajectory when the distance to the guide line is the shortest; Determine the tangent direction V1 at point P2; Determine the tangent plane S of the laid surface at point P1; V2 obtained by projecting V1 onto S is the desired laying direction of point P1.

6. The method for planning fiber placement trajectory for complex curved surfaces according to claim 5, characterized in that: The method for determining the expected laying direction corresponding to the new trajectory according to the guide line in the area includes: If the region is adjacent to two guide lines, then: Determine the points P2 and P3 on the guide lines corresponding to when any point P1 on the new trajectory reaches the closest point between the two guide lines; Determine the tangent directions V1 and V2 at points P2 and P3; According to V1 and V2, determine the weighted direction V3 of the two guide line directions; Project V3 to S to obtain the desired laying direction V4 of point P1; and / or, The method for determining the weighted direction V3 of the directions of the two guide lines according to V1 and V2 includes: The weighted direction V3=d2*V1+d1*V2; Where: d1 is the distance from P2 to P1, d2 is the distance from P3 to P1.

7. The method for planning fiber placement trajectory on a complex curved surface according to claim 1, characterized in that: The method for judging whether the new trajectory obtained after each equidistant offset meets the corresponding expected placement direction requirements includes: It is determined whether the angle between the new trajectory and the corresponding expected laying direction of the area does not exceed a predetermined value. If so, the new trajectory meets the corresponding expected laying direction requirement; otherwise, the new trajectory does not meet the corresponding expected laying direction requirement.

8. The method for planning fiber placement trajectory for a complex curved surface according to any one of claims 1 to 7, characterized in that: The method for planning and adjusting the new trajectory according to the expected laying direction includes: The direction of the new track is adjusted to the corresponding desired laying direction, and the distance between the new track and the previous current track is adjusted to minimize the overlap rate and gap rate between the two.

9. The method for planning fiber placement trajectory on a complex curved surface according to claim 2, characterized in that: The method for completing trajectory planning of a workpiece to be wire laid according to all current trajectories obtained includes: The obtained current trajectory is divided into a laying area trajectory and a non-laying area trajectory by using the closed curve; The segmented current trajectory is discretized into trajectory points, and numerical control machining codes are generated according to the trajectory points.

10. A fiber placement trajectory planning device for complex curved surfaces, characterized in that: include: A region segmentation unit is used to obtain a three-dimensional surface model of a workpiece to be wire laid, and to segment a laying surface of the three-dimensional surface model into a plurality of regions by setting a plurality of guide lines; A trajectory determination unit is used to determine the guide line in each area as the current trajectory, perform equidistant offset on the current trajectory, and determine whether the new trajectory obtained after each equidistant offset meets the corresponding expected laying direction requirements. If so, the new trajectory is determined to be the current trajectory; otherwise, the new trajectory is planned and adjusted according to the expected laying direction, and the adjusted new trajectory is determined to be the current trajectory; The trajectory planning unit is used to stop when reaching the boundary of the area or the next guide line during the equidistant offset process, and complete the trajectory planning of the workpiece to be wired based on all the current trajectories obtained.

Images