Flexible fabric suction placement method adapted to complex surfaces

Abstract

The present application relates to a kind of flexible fabric suction laying method suitable for complex surface, it uses a laying executor, the laying executor includes middle ridge module, rib module and elastic glass fiber rod;The middle ridge module includes middle ridge linear executor and middle ridge motor;The rib module includes rib linear executor, rib motor and several suction units.Middle ridge motor controls the extension and contraction of pull rod in middle ridge linear executor, makes elastic glass fiber rod deformation, forms the change of middle ridge curvature.Rib motor controls rib linear executor, changes rib module shape, forms the change of rib curvature of surface.By changing middle ridge, rib curvature, realize the change of entire plane double curvature, again by several suction units form a suction flexible fabric suction surface.The present application realizes the change of suction surface from plane state to double curved surface, so as to realize the clamping of fabric in plane, laying in complex surface.

Description

TECHNICAL FIELD

[0001] The present application relates to a fabric laying method, in particular to a flexible fabric suction laying method suitable for complex curved surfaces, and belongs to the technical field of automatic fabric laying of composite materials. BACKGROUND

[0002] Carbon fiber laying is one of the main steps in the manufacture of carbon fiber composite components. However, for complex components, carbon fiber layers are prone to form defects such as wrinkles, therefore, single-fiber laying with smaller width, compaction and shaping are often used to complete carbon fiber laying, because narrower fibers have good control characteristics. However, single-fiber laying has the problem of low efficiency, and it takes a lot of time to manufacture large-size and large-thickness components, and the production efficiency is difficult to improve, which cannot meet the increasing requirements of carbon fiber component production. Therefore, it is imperative to develop large-area fabric laying technology.

[0003] Complex curved surfaces have double curvature characteristics, and in the actual composite structure manufacturing process, multiple fabrics need to be laid on the tool surface, and the change of the size of the mold itself structure will also lead to various curvature surfaces.

[0004] Therefore, in order to adapt to these curved surface objects, it is necessary to provide an innovative flexible fabric suction laying method suitable for complex curved surfaces. SUMMARY

[0005] The purpose of the present application is to provide a flexible fabric suction laying method suitable for complex curved surfaces, which realizes the suction of fabric on the plane and the laying on the complex curved surface.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: a flexible fabric suction laying method suitable for complex curved surfaces, which adopts a laying executor, the laying executor includes a middle ridge module, a rib module and an elastic glass fiber rod; the middle ridge module includes a middle ridge linear executor and a middle ridge motor; the rib module includes a rib linear executor, a rib motor and a plurality of suction units;

[0007] The suction laying method includes the following process steps:

[0008] 1) The upper computer obtains the position information of the fabric and the required laying mold curvature, determines the motion path of the mechanical arm and the required process parameters of the laying executor;

[0009] 2) After the upper computer outputs the motion path of the mechanical arm and the required process parameters of the laying executor, the mechanical arm moves along the predetermined trajectory, and the laying executor adjusts the posture, the middle ridge motor controls the middle ridge linear executor on the middle ridge module to change the shape of the elastic glass fiber rod, and the rib motor controls the rib linear executor to change the shape of the rib module, in order to prepare for suction of the required fabric;

[0010] 3), when the mechanical arm moves to the predetermined position of the fabric that can be sucked, the suction units change the suction strength respectively through the parameters output by the host computer, and the fabric is completed to be sucked;

[0011] 4), after the fabric is completed to be sucked, the mechanical arm moves to the position to be laid along the predetermined track, the posture of the laying executor is adjusted, two curvatures are formed by the elastic glass fiber rod and the rib linear executor respectively through the control of the middle ridge motor and the rib motor, and the double curvature surface with the same curvature as the position to be laid is realized;

[0012] 5), after the mechanical arm and the laying executor move to the specified position of the fabric to be laid, the fabric is attached to the laying position, the suction units are withdrawn, then the mechanical arm moves away from the laying position, and thus the laying of the flexible fabric is completed.

[0013] The flexible fabric suction and laying method for adapting to complex surfaces further has that the middle ridge motor is connected with and controls the pull rod extension and retraction of the middle ridge linear executor; the middle ridge linear executor is connected to the elastic glass fiber rod, can change the shape of the elastic glass fiber rod, realizes the bending of the middle ridge module, and forms the main aspect curvature of the laying executor.

[0014] The flexible fabric suction and laying method for adapting to complex surfaces further has that a connecting piece is arranged on the middle ridge module, the connecting piece is connected with the mechanical arm, and thus the whole laying executor is fixedly connected to the mechanical arm.

[0015] The flexible fabric suction and laying method for adapting to complex surfaces further has that the rib linear executors are uniformly and symmetrically installed on the elastic glass fiber rod, are linked with the elastic glass fiber rod, and make the longitudinal curvature of the rib module controlled by the curvature of the middle ridge module.

[0016] The flexible fabric suction and laying method for adapting to complex surfaces further has that the rib motor is connected with and drives the rib linear executor to contract, changes the shape of the rib module, makes the transverse curvature of the rib module controlled by the displacement amount of the rib linear executor, and obtains the secondary aspect curvature of the laying executor.

[0017] The flexible fabric suction and laying method for adapting to complex surfaces further has that the adjacent suction units are connected through the spline, and thus a plurality of suction unit groups are formed; the suction unit groups are respectively installed on the rib linear executors; wherein the suction unit in the middle of each suction unit group is connected with the elastic glass fiber rod, makes the curvature of the middle part of each suction unit group consistent with the curvature of the middle ridge module; the postures of the suction units on both sides of each suction unit group are determined by the rib module, and thus the whole suction surface forms a double curvature surface.

[0018] The flexible fabric suction placement method for complex curved surfaces of the present application further comprises that in step 1), a total of 145 process parameters are selected for the placement executor: 3 parameters for the middle ridge motor position, 15 parameters for the rib motor position, and 127 parameters for the strength of each suction unit.

[0019] The flexible fabric suction placement method for complex curved surfaces of the present application further comprises that the control method of the upper computer comprises the following steps:

[0020] 1-1), the CATIA software is used to integrate the to-be-placed curved surface mold model and the placement executor into the CAD model; with the help of CATScript macro and the python framework, the placement executor is moved to the position of the to-be-placed curved surface mold model; then, the ridges and ribs of the placement executor are deformed, and the distance between the suction surface and the mold surface is measured after each deformation step;

[0021] 1-2), the off-line programming software calculates the travel of the middle ridge linear executor and the rib linear executor according to the deformation parameters of the ridges and ribs, according to the expected position of the placement executor, and solves the motion parameters of each joint of the mechanical arm to plan the motion trajectory of the mechanical arm;

[0022] 1-3), the servo motor corresponding to each joint of the mechanical arm drives the joint to move according to the given motion trajectory of the software, so that the placement executor reaches the expected position; the middle ridge motor and the rib motor are reversed to drive the pull rod in the middle ridge linear executor to contract, change the shape of the middle ridge and the rib, and make the curvature of the suction surface consistent with the curvature of the to-be-placed mold;

[0023] 1-4), after the above steps are completed, the fabric is placed according to the predetermined placement position;

[0024] 1-5), after the placement is completed, the mechanical arm is reversely moved back to the initial position, the middle ridge motor and the rib motor are forward rotated to drive the pull rod in the middle ridge linear executor to elongate, and the suction surface is changed from a hyperboloid to a plane, preparing for suction of the next organization object.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] 1. The present application can be applied to low-defect placement of flexible fabric for complex curved surfaces, which controls the deformation of the elastic glass fiber rod through the middle ridge motor to form the change of the middle ridge curvature, controls the shape of the rib module through the rib motor to form the change of the rib curvature of the curved surface, so that it can adapt to double-curvature curved surfaces with different curvatures through the size change of the structure of the device itself.

[0027] 2. In the placement process, no human intervention is needed, and the fabric can be adsorbed on the surface of the device through the suction unit, effectively avoiding wrinkles of the fabric in the placement process. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a perspective view of a flexible fabric suction placement placement executioner of the present application which is suitable for complex curved surface.

[0029] Figure 2 is Figure 1 is an array view of suction units in

[0030] Figure 3 is Figure 1 is an installation schematic view of elastic glass fiber rod and rib linear executioner in

[0031] Figure 4 is Figure 1 is a perspective view of a middle ridge module in

[0032] Figure 5 is Figure 1 is a partial enlarged view of A in

[0033] Figure 6 is a schematic view of a placement executioner of the present application installed on a mechanical arm. DETAILED DESCRIPTION

[0034] Please refer to the drawings in the description of the present application Figure 1 to the drawings, which is a placement executioner of the present application which is suitable for flexible fabric suction placement of complex curved surface, which adopts middle ridge-rib structure to construct hyperboloid structure, and is composed of middle ridge module 100, rib module 200, elastic glass fiber rod 3 and other parts. Figure 6

[0035] The middle ridge module 100 is composed of middle ridge linear executioner 1 and middle ridge motor 2 and other parts. The middle ridge motor 2 is connected to and controls the extension and retraction of the pull rod 11 of the middle ridge linear executioner 1. The middle ridge linear executioner 1 is connected to the elastic glass fiber rod 3, which can change the shape of the elastic glass fiber rod 3, realize the bending of the middle ridge module 100, and form the main aspect curvature of the placement executioner. Further, a connecting piece 7 is arranged on the middle ridge module 100, and a transmission mechanism is installed in the connecting piece 7. The connecting piece 7 is connected to the mechanical arm 300, so as to fix the whole placement executioner on the mechanical arm 8.

[0036] ​The rib module 200 is composed of several parts such as rib linear actuators 4, rib motors 5 and several suction units 6. Among them, the rib linear actuators 4 are uniformly and symmetrically installed on the elastic glass fiber rod 3, and are linked with the elastic glass fiber rod 3, so that the longitudinal curvature of the rib module 200 is controlled by the curvature of the spine module 100. The rib motor 5 is connected and drives the rib linear actuator 4 to contract, so as to change the shape of the rib module 200, so that the transverse curvature of the rib module 200 is controlled by the displacement amount of the rib linear actuator 4, and the secondary aspect curvature of the laying actuator is obtained.

[0037] Further, adjacent suction units 6 are connected through splines 8, thereby forming several suction unit groups. In the embodiment, the suction unit groups are divided into 15 groups, as shown in the accompanying drawings. Figure 2 The suction unit groups are respectively installed on the rib linear actuators 4 and driven by the rib linear actuators 4. Among them, the suction unit 6 in the middle of each group of suction unit groups is connected with the elastic glass fiber rod 3, so that the curvature of the middle part of each group of suction unit groups is consistent with the curvature of the spine module 100. The posture of the suction units 6 on both sides of each group of suction unit groups is determined by the rib module 200, so that the entire suction surface forms a double curvature surface.

[0038] The design principle of the laying actuator is as follows:

[0039] 1), the main body is composed of the elastic glass fiber rod 3 as the basic material, which forms a stable bendable frame structure and serves as the spine mechanism of the actuator, and adapts to the change of the main aspect curvature of the curved surface. The spine linear actuator 1 is arranged on the spine, and the flexible spine model 100 is established, the displacement amount of the spine linear actuator 1 is associated with the deformation amount of the spine, after the geometric size of the curved surface to be laid is determined, the displacement amount of the spine linear actuator 1 is controlled and adjusted by the spine motor 2, so that the curvature of the spine of the laying actuator is consistent with the one-way curvature of the curved surface to be laid.

[0040] 2), the parallel rib module 200 is arranged on the spine, the rib linear actuator 4 is installed on the rib module 200, the displacement amount of the rib linear actuator 4 is changed by the rib motor 5, so that the rib module 200 can be deformed and bent, and adapt to the change of the secondary aspect curvature of the curved surface to be laid; at the same time, the array of suction units 6 with vacuum suction cups is arranged, and the airflow and suction force of the single suction unit 6 can be adjusted.

[0041] The method for sucking and laying the flexible fabric on the complex curved surface by using the above laying actuator includes the following process steps:

[0042] 1), the host computer obtains the position information of the fabric and the required laying mold curvature, determines the motion path of the robot arm 8 and the required process parameters of the laying actuator. Among them, the laying actuator needs to select a total of 145 process parameters: 3 parameters for the middle ridge motor position, 15 parameters for the rib motor position, and 127 parameters for the strength of each suction unit.

[0043] 2), after the host computer outputs the required process parameters of the laying actuator and the motion path of the robot arm, the robot arm moves along the predetermined trajectory, while the laying actuator adjusts the posture, the middle ridge motor 2 controls the middle ridge linear actuator 1 on the middle ridge module to change the shape of the elastic glass fiber rod 3, and the rib motor 5 controls the rib linear actuator 4 to change the shape of the rib module 200 to prepare for suction of the required fabric.

[0044] 3), when the robot arm moves to the predetermined position where the fabric can be sucked, the suction units 6 change the suction strength respectively through the parameters output by the host computer, and the suction of the fabric is completed.

[0045] 4), after the fabric is sucked, the robot arm moves along the predetermined trajectory to the laying position, during which the laying actuator adjusts the posture, and through the control of the middle ridge motor 2 and the rib motor 5, the elastic glass fiber rod 3 and the rib linear actuator 4 form two curvatures respectively to realize the double curvature surface with the same curvature as the laying position.

[0046] 5), after the robot arm and the laying actuator move to the specified position of the laid fabric, the fabric is attached to the laying position, the suction units 6 are removed, and then the robot arm moves away from the laying position, thus completing the laying of the flexible fabric.

[0047] Further, the control method of the host computer is as follows:

[0048] 1-1), use CATIA software to integrate the laying surface mold model and the laying actuator into the CAD model; with the help of CATScript macro and python framework, the laying actuator is moved to the position of the laying surface mold model; then, the spine and ribs of the laying actuator are deformed, and the distance between the suction surface and the mold surface is measured after each deformation step. This simulation can provide the desired position and direction of the end effector, appropriate deformation parameters, and the target profile of the fabric on the end effector.

[0049] 1-2), the off-line programming software calculates the motion parameters of each joint of the robot arm according to the desired position of the laying actuator to plan the motion trajectory of the robot arm, and calculates the stroke of the middle ridge linear actuator and the rib linear actuator according to the deformation parameters of the spine and ribs.

[0050] 1-3), the servomotor corresponding to each joint of the mechanical arm drives the joint to move according to the software given motion trajectory, so that the laying executor reaches the desired position; the middle ridge motor 2 and the rib motor 5 are reversed to drive the pull rod in the middle ridge linear executor 1 to contract, change the shape of the middle ridge and the rib, and make the curvature of the suction surface consistent with the curvature of the to-be-laid mold.

[0051] 1-4), after the above steps are completed, the fabric is laid according to the predetermined laying position.

[0052] 1-5), after the laying is completed, the mechanical arm moves reversely back to the initial position, the middle ridge motor 2 and the rib motor 5 are forward rotated to drive the pull rod in the middle ridge linear executor 1 to elongate, the suction surface is changed from a double curved surface to a plane, and the next organization object is prepared to be sucked.

[0053] The above specific embodiments are only the preferred embodiments of the present application, and are not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A flexible fabric tape laying method for complex surfaces, characterized in that: It adopts a laying actuator which comprises a middle ridge module, a rib module and a flexible glass fiber rod; the middle ridge module comprises a middle ridge linear actuator and a middle ridge motor; the rib module comprises a rib linear actuator, a rib motor and a plurality of suction units; The suction laying method comprises the following process steps: 1) The upper computer obtains the position information of the fabric and the required laying mold curvature, determines the movement path of the mechanical arm and the required process parameters of the laying actuator; 2) After the upper computer outputs the movement path of the mechanical arm and the required process parameters of the laying actuator, the mechanical arm moves along the predetermined trajectory, and the laying actuator adjusts the posture, the middle ridge motor controls the middle ridge linear actuator on the middle ridge module to change the shape of the flexible glass fiber rod, and the rib motor controls the rib linear actuator to change the shape of the rib module to prepare for suction of the required fabric; 3) After the mechanical arm moves to the predetermined position where the fabric can be sucked, the suction units change the suction strength respectively through the parameters output by the upper computer, and the suction of the fabric is completed; 4) After the suction of the fabric is completed, the mechanical arm moves to the laying position along the predetermined trajectory, and the laying actuator adjusts the posture in the process, and through the control of the middle ridge motor and the rib motor, two curvatures are formed by the flexible glass fiber rod and the rib linear actuator respectively to realize the double curvature surface with the same curvature as the laying position; 5) After the mechanical arm and the laying actuator move to the specified position of the laid fabric, the fabric is attached to the laying position, the suction units are removed, and then the mechanical arm moves away from the laying position, thus completing the laying of the flexible fabric.

2. The flexible fabric tape laying method for conforming to complex surfaces of claim 1, wherein: The middle ridge motor connects and controls the extension and retraction of the pull rod of the middle ridge linear actuator; the middle ridge linear actuator is connected to the flexible glass fiber rod, which can change the shape of the flexible glass fiber rod to realize the bending of the middle ridge module and form the main aspect curvature of the laying actuator.

3. The flexible fabric tape laying method for conformal surfaces of claim 2, wherein: A connecting piece is arranged on the middle ridge module, which is connected with the mechanical arm to fix the whole laying actuator on the mechanical arm.

4. The flexible fabric tape laying method for conforming to complex surfaces of claim 1, wherein: The rib linear actuators are uniformly and symmetrically installed on the flexible glass fiber rod, which are linked with the flexible glass fiber rod to make the longitudinal curvature of the rib module controlled by the curvature of the middle ridge module.

5. The flexible fabric tape laying method for conformal surfaces of claim 4, wherein: The rib motor connects and drives the rib linear actuator to contract to change the shape of the rib module, so that the transverse curvature of the rib module is controlled by the displacement amount of the rib linear actuator to obtain the secondary aspect curvature of the laying actuator.

6. The flexible fabric tape laying method for conforming to complex surfaces of claim 1, wherein: The adjacent suction units are connected by spline to form a plurality of suction unit groups; the suction unit groups are respectively installed on the rib linear actuators; wherein the suction unit in the middle of each suction unit group is connected with the flexible glass fiber rod, so that the curvature of the middle part of each suction unit group is consistent with the curvature of the middle ridge module; the postures of the suction units on both sides of each suction unit group are determined by the rib module, so that the whole suction surface forms a double curvature surface.

7. The flexible fabric tape laying method for conformal surfaces of claim 1, wherein: In step 1), a total of 145 process parameters are selected for the laying actuator: 3 parameters for the middle ridge motor position, 15 parameters for the rib motor position, and 127 parameters for the strength of each suction unit.

8. The flexible fabric tape laying method for conforming to complex surfaces of claim 1, wherein: The control method of the upper computer comprises the following steps: 1-1), the mold model of the surface to be laid and the laying actuator are integrated into the CAD model using CATIA software; with the help of CATScript macro and python framework, the laying actuator is moved to the position of the mold model of the surface to be laid; then, the spine and ribs of the laying actuator are deformed, and the distance between the suction surface and the mold surface is measured after each deformation step; 1-2), the off-line programming software calculates the stroke of the middle spine linear actuator and the rib linear actuator according to the expected position of the laying actuator, and solves the motion parameters of each joint of the robot arm using inverse kinematics for robot arm motion trajectory planning, and calculates the stroke of the middle spine linear actuator and the rib linear actuator according to the deformation parameters of the spine and ribs; 1-3), the servo motor corresponding to each joint of the robot arm drives the joint to move according to the software given motion trajectory, so that the laying actuator reaches the expected position; the middle spine motor and the rib motor are reversed, the pull rod in the middle spine linear actuator is retracted, the shape of the middle spine and the rib is changed, and the curvature of the suction surface is consistent with the curvature of the mold to be laid; 1-4), after the above steps are completed, the fabric is laid according to the predetermined laying position; 1-5), after laying is completed, the robot arm moves reversely to the initial position, the middle spine motor and the rib motor are forward rotated, the pull rod in the middle spine linear actuator is elongated, the suction surface is changed from a hyperboloid to a plane, and the next tissue is prepared for suction.

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