Robot and method for sewing object
By designing robotic systems for sewing objects in the automotive industry, using the precise path movement of pre-sewn stitches and controllers, the labor-intensive problems of leather cover fixing and sewing processes are solved, and automated sewing is achieved and improved Production efficiency and product quality.
Patent Information
- Application Number
- CN202280095874.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2022-05-24
- Publication Date
- 2024-12-24
AI Technical Summary
In the automotive industry, the fixing and sewing process of leather coverings relies on manual work, resulting in labor-intensive and time-consuming assembly, lacking automated solutions.
Design a robot system for sewing objects, using robot arms and controllers to perform sewing operations on the surface of flexible material through pre-sewn stitches, the needle moving along a path defined between the bottom side and the outer surface of the line segment to avoid physical Penetrates the body to reduce scratches and scratches.
The possibility of automatic sewing on soft materials is realized, the sewing operation performed by the robot is simplified, scratches and scratches caused by accidental contact are reduced, and production efficiency and product quality are improved.
Smart Images
Figure CN119183407A_ABST
Abstract
Description
Technical Field
[0001] Embodiments of the present disclosure relate generally to the field of industrial robots, and more particularly to industrial robots for sewing objects. Background Art
[0002] In the automotive industry, more and more cars are being manufactured to be equipped with leather-covered steering wheels. Leather not only improves the appearance of the steering wheel, but also improves the comfort of the feel. This is because the leather covering resists the slippery feeling caused by sweat, which means safer driving.
[0003] Typically, leather coverings are manually attached to the raw steering wheel by hand using manual work. The worker first attaches the leather covering to the raw steering wheel by gluing and then sews the leather covering to the raw steering wheel by sewing stitch by stitch. This is labor-intensive and time-consuming. For a single steering wheel, to complete this assembly process, it takes one hour even for an experienced operator. There is an increasing need to automate the assembly process by means of industrial robots. Summary of the invention
[0004] Exemplary embodiments of the present disclosure provide a robot and method for sewing an object, which can achieve automatic sewing using a needle.
[0005] In a first aspect of the present disclosure, a robot for sewing an object is provided. The robot for sewing an object comprises: a robot arm configured to hold a needle, the needle being pre-tied with a thread, and a controller configured to move the needle, wherein the object comprises a flexible outer surface and pre-stitches formed on the outer surface, each of the pre-stitches comprising a thread segment, the thread segment comprising a top side and an opposite bottom side, the bottom side facing the outer surface, and the controller is configured to perform a sewing operation by passing the needle through the thread segment along a path defined between the bottom side of the thread segment and the outer surface of the object.
[0006] According to the present disclosure, due to the arrangement of the pre-sewn stitches, in order to perform suturing on soft materials, the needle does not have to physically penetrate the body of the object, and the sewing operation performed by the robot can be simplified. Moreover, since the needle is passed through the thread segment along a path defined between the bottom side of the thread segment and the outer surface of the object, scratches caused by accidental contact with the object can be further reduced. Through the above arrangement, automatic suturing can be performed on soft and flexible materials by a robot using a needle.
[0007] In some embodiments, the controller may be configured to: determine a position to be sewn corresponding to the line segment of the pre-sewn stitch; move the needle to a preparation position located at a first lateral side of the line segment, the preparation position being offset from the position to be sewn by an offset distance; determine the posture of the needle so that the longitudinal axis of the needle is tangent to the outer surface where the path on the object is located; and when the needle is in the determined posture, move the needle from the first lateral side of the line segment to the opposite second lateral side of the line segment by a first distance so that the needle passes over the line segment, the first distance being greater than the offset distance.
[0008] In some embodiments, the robot may further include a camera for capturing an image of the object, wherein the position to be sewn and a tangent angle at which the needle is tangent to the outer surface are determined based on the captured image.
[0009] In some embodiments, the controller may be configured to: at the preparation position, press the needle toward the outer surface in a direction perpendicular to the outer surface to deform the outer surface of the object.
[0010] In some embodiments, the robot may further include a force sensor attached to the robot arm for sensing a contact force between the needle and the object, wherein a degree of compression is determined based on the sensed contact force, the degree of compression being determined in association with a material of the object.
[0011] In some embodiments, the controller may be configured to: while the needle remains pressed, linearly move the needle from the first lateral side of the thread segment by the first distance to the opposite second lateral side of the thread segment.
[0012] In some embodiments, the controller may be configured to: adjust the posture of the needle so that the needle tip of the needle tilts upward away from the outer surface after moving the first distance; and move the needle a second distance in the adjusted posture.
[0013] In some embodiments, the degree of inclination of the needle tip may be determined so that further movement of the needle tip does not interfere with other pre-sewn stitches.
[0014] In some embodiments, the object may include a covering pre-wrap around a steering wheel, the covering being made of leather, artificial leather, or fabric.
[0015] In a first aspect of the present disclosure, a method for sewing an object is provided. The method includes: holding a needle by a robot arm, the needle being pre-tied with a thread, and performing a sewing operation by a controller by making the needle pass over the thread segment from the bottom side of the thread segment, wherein the object includes a flexible outer surface and pre-sewn stitches formed on the outer surface, each of the pre-sewn stitches includes the thread segment, the thread segment includes a top side and an opposite bottom side, the bottom side facing the outer surface.
[0016] In some embodiments, the method may also include: determining, by the controller, a position to be sewn corresponding to the line segment of the pre-sewn stitch; moving, by the controller, the needle to a preparation position located at a first lateral side of the line segment, the preparation position being offset from the position to be sewn by an offset distance; determining, by the controller, a posture of the needle so that the longitudinal axis of the needle is tangent to an outer surface of the object, the outer surface being located at the line segment through which the needle passes; and when the needle is in the determined posture, by the controller, moving the needle from the first lateral side of the line segment a first distance to the opposite second lateral side of the line segment so that the needle passes through the line segment, the first distance being greater than the offset distance.
[0017] In some embodiments, the method may further include determining the to-be-sewn position and a tangent angle at which the needle is tangent to the outer surface based on a captured image captured by a camera.
[0018] In some embodiments, the method may also include: at the preparation position, pressing the needle toward the outer surface in a direction perpendicular to the outer surface to deform the outer surface of the object, and the degree of pressing is determined based on the contact force sensed by the force sensor attached to the robot arm.
[0019] In some embodiments, the method may further include: while the needle maintains the pressing state, linearly moving the needle from the first lateral side of the wire segment by the first distance to the opposite second lateral side of the wire segment.
[0020] In some embodiments, the method may also include: adjusting the posture of the needle so that the needle tip is tilted upward away from the outer surface after moving the first distance, wherein the degree of inclination of the needle tip is determined so that further movement of the needle tip does not interfere with other pre-sewn stitches; and moving the needle a second distance in the adjusted posture.
[0021] In some embodiments, the object may include a covering pre-wrap around a steering wheel, the covering being made of leather, artificial leather, or fabric. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The above and other objects, features and advantages of the exemplary embodiments disclosed herein will become more easily understood through the following detailed description with reference to the accompanying drawings. In the accompanying drawings, several exemplary embodiments disclosed herein are shown by way of example and not limitation, in which:
[0023] Figure 1 is a schematic diagram of a robot for sewing an object according to an exemplary embodiment of the present disclosure;
[0024] Figure 2 is a schematic diagram of a robot for sewing an object according to another exemplary embodiment of the present disclosure;
[0025] Figure 3 is a schematic perspective view of stitches sewn by a robot for sewing an object according to an exemplary embodiment of the present disclosure;
[0026] Figure 4 is a schematic enlarged view of a portion of a robot for sewing an object according to another exemplary embodiment of the present disclosure, illustrating a positional relationship between a needle prepared for performing a sewing operation and an object;
[0027] Figure 5-Figure 8 is a schematic cross-sectional process diagram illustrating the principle of how a needle is operated to penetrate the object to perform sewing according to an exemplary embodiment of the present disclosure, showing different states of the needle relative to a pre-sewn stitch;
[0028] Fig. 9 is a flowchart of a method for sewing an object according to an exemplary embodiment of the present disclosure.
[0029] Throughout the drawings, the same or similar reference numbers are used to refer to the same or similar elements. DETAILED DESCRIPTION
[0030] The principles of the present disclosure will now be described with reference to several example embodiments shown in the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that these embodiments are described only to facilitate those skilled in the art to better understand and thereby implement the present disclosure, rather than to limit the scope of the present disclosure in any way.
[0031] The terms "including" or "comprising" and their variations should be interpreted as open-ended terms, which mean "including but not limited to". The term "or" should be interpreted as "and / or", unless the context clearly indicates otherwise. The term "based on" should be understood as "based at least in part on". The term "operably" refers to a function, action, movement or state that can be achieved through operation caused by a user or an external mechanism. The terms "one embodiment" and "embodiment" should be understood as "at least one embodiment". The term "another embodiment" should be understood as "at least one other embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may be included below. Unless the context clearly indicates otherwise, the definitions of terms are consistent throughout the specification.
[0032] There is an increasing need to automate the assembly process of sewing a cover onto a steering wheel. The present invention proposes a novel robotic system for sewing, which can sew a cover onto a steering wheel. It should be understood that although the present disclosure uses a steering wheel with a cover as an example to illustrate the principles of the present invention, this is merely illustrative and the concept of the present invention can be applied to any other object that needs to be sewn.
[0033] Figure 1 A robotic system 100 for sewing an object is shown. Figure 1 As shown, the robot system 100 includes a support 140 for supporting an object to be sewn (in the example shown, a steering wheel 190), a first robot arm 120, and a second robot arm 130. The object may be a semi-finished product transferred from a previous process, and may include a covering and a blank steering wheel. The covering may be substantially bonded to the blank steering wheel, and the covering should be further sewn according to a predetermined sewing pattern so as to tightly fix the covering to the blank steering wheel. The robot system 100 is configured to perform the above-mentioned sewing operation.
[0034] The robotic system 100 also includes a controller 110 that can communicate with the first robotic arm 120 and the second robotic arm 130 to control their movements to perform sewing operations.
[0035] The robot system 100 may also include one or more cameras 152, 154. The cameras 152 and 154 may be connected to different locations of the robot system so as to obtain images of the object from different perspectives. The image of the object may be sent to the controller 110. In some embodiments, the controller is configured to visually inspect the object based on the image from the camera, and provide an inspection result indicating whether the object can be sewn by the device before the sewing operation. In some embodiments, the sewing quality after the sewing operation may be provided. In some embodiments, the controller 110 is configured to identify multiple positions to be sewn based on the image from the camera and generate a sewing path. The sewing path determines the sewing pattern based on the input rules of the pattern preparation based on the identified multiple positions to be sewn, and the sewing pattern defines the positions to be sewn in sequence. According to the sewing path, the controller controls the first robot arm 120 and the second robot arm 130 to perform the sewing operation. Through multiple sewing operations, multiple stitches are automatically formed.
[0036] The first robot arm 120 and the second robot arm 130 are arranged adjacent to the support 140 and thus can approach the steering wheel 190 to perform the sewing operation. The first robot arm 120 and the second robot arm 130 each include a gripper configured to hold the needle 180. The support 140 may include a rotatable shaft so that the position of the steering wheel 190 can be adjusted according to the position of the steering wheel 190 to be sewn.
[0037] The sewing operation of the robot system 100 is as follows. The first robot arm 120 first holds the needle 180, and the needle 180 is tied to a certain length of thread 185. The second robot arm 130 is in a standby position. The controller 110 identifies the position to be sewn and instructs the first robot arm 120 to move to the identified position to be sewn so that the needle 180 penetrates a portion of the steering wheel 190. Then, the controller 110 instructs the second robot arm 130 to hold the penetrated portion of the needle 180, and pull the entire needle 180 out of the steering wheel 190 after the needle 180 is released by the first robot arm 120.
[0038] As a material for covering the steering wheel, the cover is generally soft and has a certain toughness to improve the hand's control feeling. In some embodiments, the cover is made of leather, artificial leather, fabric, etc. On the other hand, the needle generally has a sharp needle tip, which means that there is a high possibility that the needle may scratch the outer surface of the cover. This means that once the sharp needle tip of the needle directly contacts the outer surface of the cover, the cover is likely to be pierced by the needle, which destroys the appearance of the cover and reduces product quality.
[0039] Therefore, the sewing process requires that the needle must penetrate a portion of an object or a covering without scratching it. The present disclosure provides a novel robot for sewing an object, which is capable of penetrating a portion of a covering made of a flexible material without the risk of scratching it. According to an exemplary embodiment of the present disclosure, pre-sewn stitches, such as two rows of pre-sewn stitches, are formed on an outer surface, and the pre-sewn stitches define a sewing area. Appropriate pre-sewn stitches are selected, and the needle is moved to penetrate these selected pre-sewn stitches, respectively. Through this process, a portion of an object or a covering can be penetrated without scratching it, especially when a sewing operation is performed on the surface of a soft material.
[0040] Figure 2 A robotic system 200 is shown for sewing an object having a soft outer surface. Figure 2 As shown, the robot system 200 includes a robot arm 220 and a controller 210. An object 290 to be sewn (e.g., a leather covering) can be placed in an appropriate position accessible to the robot arm 220. The controller 210 can communicate with the robot arm 220 to control its movement to perform the sewing operation. The robot arm 220 may include a clamp for holding a needle 280. The root of the needle includes a hole. A thread 285 passes through the hole and is tied to the needle 280. The tip portion of the needle 280 is sharp and can penetrate the object. In some embodiments, for example, with reference to Figure 3 and Figure 5 , the object 290 includes a flexible outer surface 297 and pre-sewn stitches formed on the outer surface 297, each pre-sewn stitch includes a thread segment 292, and the thread segment 292 includes a top side 293 and an opposite bottom side 295 facing the outer surface 297. The controller 210 is configured to perform a sewing operation by passing the needle 280 through the thread segment 292 along a path defined between the bottom side 295 of the thread segment 292 and the outer surface 297 of the object 290. When the needle 280 is moved by the robot and penetrates the object, the thread 285 penetrates the object accordingly. After multiple sewing operations, a plurality of stitches are formed on the object, so that the object is sewn by the needle 280 and the thread 285.
[0041] Figure 3 FIG. 2 is a schematic perspective view of a sewing stitch 285 of a robot 200 for sewing an object according to an exemplary embodiment of the present disclosure. Figure 3 As shown, two rows of pre-sewn stitches are formed on the outer surface of the object in advance. Each pre-sewn stitch includes a thread segment. The thread segment has a top side facing the upward direction and an opposite bottom side facing the outer surface. In order to perform the sewing operation, the needle moves on the thread segment along a path defined between the bottom side of the thread segment and the outer surface of the object. Therefore, since the needle does not have to penetrate the body 296 of the object 290 (see also Figure 5 ), so scratches caused by the needle can be reduced.
[0042] Return to reference Figure 2 The robot system 200 may also include one or more cameras 252. The camera 252 may be attached to an appropriate location of the robot system and configured to obtain an image of the object. The image of the object may be sent to the controller 210. The controller 210 is configured to identify a plurality of locations to be sewn, i.e., a plurality of pre-sewn stitches, based on the image from the camera. Figure 3 As shown, when the needle passes through each selected pre-sewn stitch, a sewing pattern is produced. It should be understood that Figure 3 The sewing patterns in are merely illustrative, and the sewing patterns may be in any other suitable form.
[0043] Figure 4 2 is a schematic enlarged perspective view of a portion of a robot for sewing an object, and shows a positional relationship between a needle 280 held by a robot arm 220 and an object 290 to be sewn. Figure 4 As shown, also refer to Figure 5 , the object 290 includes a flexible covering 294 and a body 296. In this embodiment, when the object 290 is a steering wheel, the body 296 is a blank steering wheel. The flexible covering 294 can be substantially bonded to the body 296. The flexible covering 294 can be provided with two rows of pre-sewn stitches 292, and the area between the two rows of pre-sewn stitches 292 defines a sewing area. The needle 280 carries a certain length of thread 285 and can move from one lateral side of each pre-sewn stitch 292 to the other lateral side of each pre-sewn stitch 292. Through this movement of the needle, the thread 285 also moves from one lateral side of each pre-sewn stitch 292 to the other lateral side of each pre-sewn stitch 292. For each selected pre-sewn stitch 292, the needle repeats the above steps. Thus, a plurality of stitches are formed by the thread 285. Therefore, the covering 294 is sewn to the body 296 by tightening the covering 294 around the body 296.
[0044] like Figure 4 As shown, the needle 280 is held by the robot arm 220 and can be moved by the robot arm 220. The object 290 has a line segment 292 of a plurality of pre-sewn stitches. The position of the needle is represented by P(x, y, z; β). In some embodiments, the position information is acquired by a controller and an associated sensor (e.g., a camera). In P(x, y, z; β), x, y, z represent coordinates in a coordinate system, the xy plane represents the horizontal plane at the position Q to be sewn on the object 290 (which corresponds to a line section of a pre-sewn stitch), and the z axis represents the direction perpendicular to the xy plane. The angle β represents the angle formed by the tip of the needle relative to the xy plane. It should be understood that P(x, y, z; β) is merely illustrative and the position of the tip of the needle can be represented by any other appropriate coordinate system. In Figure 4, the needle tip has coordinates (x, y, z; β) and is offset by Δx, Δy, Δz relative to the sewing position Q. The controller can use this information to control the robot arm 220 to move the needle 280 (particularly the needle tip) to the appropriate position to perform sewing.
[0045] Figure 5-Figure 8 is a schematic cross-sectional process diagram illustrating a principle of operating a needle to penetrate an object to perform sewing according to an exemplary embodiment of the present disclosure, showing different states of the needle relative to a pre-sewn stitch. Figure 5-Figure 8 Similar to Figure 4 , but a plan view of the yz plane is shown, in which the relative position between the needle and the object can be better shown.
[0046] exist Figure 5 In the case of a needle, the needle is in a deflected position before penetrating the object. Figure 5 As shown, also refer to Figure 4 The object 290 includes a covering 294 having a flexible outer surface 297 and a plurality of pre-sewn stitches formed on the outer surface 297 (in Figure 5 Each pre-sewn stitch includes a thread segment 292 including a top side 293 and an opposite bottom side 295 facing an outer surface 297. To ensure that there are no scratches, the needle 280 is controlled to pass through the thread segment 292 along a path defined between the bottom side 295 of the thread segment 292 and the outer surface 297 of the object 290.
[0047] Assuming that the needle penetrates the line segment 292 (ie, the line segment 292 located on the left side of the line segment 292), it Figure 5 denoted by Q in FIG. The position Q is determined, for example, by the camera 252. The position P of the needle tip is also known to the robot. Therefore, the relative relationship between the needle tip and the position Q is known to the controller.
[0048] The orientation of the needle penetrating the object is determined by the controller so that the longitudinal axis of the needle is tangent to the outer surface of the object where the path is located. In other words, the longitudinal axis of the needle should be in the xy plane. This means that when the needle penetrates the object or passes through the line segment 292, the direction of the needle tip is always tangent to the outer surface of the object at position Q. By these measures, the orientation of the needle tip can be accurately controlled and scratches caused by the needle tip are reduced.
[0049] Once the above parameters are determined, the robotic arm 220 is lowered onto the object 290 and, with the needle in the determined posture, moves the needle from a first lateral side of the thread segment 292 to an opposite second lateral side of the thread segment to allow the needle to pass through the thread segment. In this manner, the needle can penetrate the thread segment 292 with fewer or no scratches. In some embodiments, the first distance is greater than the offset distance. This ensures that the needle penetrates the thread segment 292.
[0050] In some embodiments, in the preparation position, the needle is pressed toward the outer surface in a direction perpendicular to the outer surface so as to deform the outer surface of the object. Figure 6 As shown, before penetrating the object, the needle is in a ready position, and the needle is a first distance away from position Q. Moreover, the needle tip is tangent to the outer surface of the object at position Q. Figure 6 In the embodiment, when the needle is pressed toward the outer surface in a direction perpendicular to the outer surface, a gap 298 is formed between the bottom side 295 of the wire segment 292 and the outer surface 297 of the object 290. By pressing the outer surface of the object in the z direction, the gap 298 can be formed between the bottom side 295 of the wire segment 292 and the outer surface 297 of the object 290. Due to the generated gap 298, there is no scratch when the needle passes through the wire segment 292. Therefore, scratches caused by the needle tip can be completely avoided.
[0051] It should be understood that this is merely illustrative and not restrictive. In some embodiments, the step of pressing the needle may be omitted. For example, when a small gap is initially formed between the line segment of the pre-sewn stitches and the outer surface of the object and the needle can penetrate the small gap, it may not be necessary to press the needle.
[0052] In some embodiments, the robot may further include a force sensor attached to the robot arm. The force sensor is configured to sense the contact force between the needle and the object. In this way, the degree of compression is determined based on the sensed contact force. In some embodiments, the degree of compression is determined in association with the material properties of the object (e.g., the hardness of the covering). Using the force sensor, the force used to deform the outer surface of the object can be accurately controlled.
[0053] like Figure 6 and Figure 7 As shown, with the needle held in the depressed state, the needle 280 moves a first distance from a first lateral side of the thread segment to an opposite second lateral side of the thread segment. The needle passes through the thread needle without obstruction.
[0054] In some embodiments, Figure 8 As shown, the posture of the needle can be further adjusted so that the needle tip of the needle leaves the outer surface upwardly tilted after moving the first distance. For example, the posture of the needle can be adjusted by rotating the needle, such as Figure 8As shown by the arrow in . In some embodiments, the degree of inclination of the needle tip of the needle is determined so that further movement of the needle tip does not interfere with other pre-sewn stitches. Then, the needle moves a second distance with an adjusted posture. At the second distance, the needle can be pulled out, for example, by a robot arm or any other appropriate device. Thus, a sewing operation of one stitch is achieved. It should be understood that adjusting the posture of the needle is merely illustrative and not restrictive. In some embodiments, if the movement of the needle tip does not interfere with other pre-sewn stitches, the steps can be avoided.
[0055] Fig. 9 FIG. 3 is a flow chart of a method 300 for sewing an object according to an exemplary embodiment of the present disclosure. Fig. 9 As shown, method 300 includes the following actions. In box 302, a needle is held by a robot arm, wherein the needle is pre-tied with a thread. In box 304, the needle is moved, for example, by a controller, to pass over the thread segment from the bottom side of the thread segment. The object includes a flexible outer surface and pre-sewn stitches formed on the outer surface, each pre-sewn stitch includes a thread segment, and the thread segment includes a top side and an opposite bottom side facing the outer surface. Through the arrangement of the pre-sewn stitches, the method of the present disclosure can easily penetrate an object made of a soft material.
[0056] In some embodiments, the position to be sewn of the thread segment corresponding to the pre-sewn stitch is determined. The needle moves to a ready position located at a first lateral side of the thread segment, and the thread segment is offset from the position to be sewn by an offset distance. The posture of the needle is determined so that the longitudinal axis of the needle is tangent to the outer surface of the thread segment on the object where the needle passes through. When the needle is in a determined posture, the needle moves a first distance from the first lateral side of the thread segment and reaches the opposite second lateral side of the thread segment so that the needle passes through the thread segment, and the first distance is greater than the offset distance. Through this arrangement, scratches caused by the needle tip can be reduced.
[0057] In some embodiments, the position to be sewn and the tangent angle at which the needle is tangent to the outer surface can be determined based on the captured image captured by the camera. In this way, the position to be sewn and the tangent angle can be easily determined. It should be understood that this is merely illustrative and not restrictive, and any other appropriate device can be used to determine the position to be sewn and the tangent angle.
[0058] In some embodiments, in the preparation position, the needle can be pressed toward the outer surface in a direction perpendicular to the outer surface so as to deform the outer surface of the object, the degree of pressing being determined based on the contact force sensed by the force sensor attached to the robot arm. In this way, scratches caused by the needle tip can be minimized.
[0059] In some embodiments, when the needle is kept in the pressed state, the needle can be linearly moved from a first lateral side of the line segment to a first distance and reach an opposite second lateral side of the line segment. Through linear movement, the posture of the needle can be well maintained to avoid shaking of the needle tip.
[0060] In some embodiments, the posture of the needle can be adjusted so that after moving a first distance, the needle tip is tilted upward away from the outer surface, wherein the degree of inclination of the needle tip is determined so that further movement of the needle tip does not interfere with other pre-sewn stitches. With the adjusted posture, the needle is moved a second distance. This is particularly advantageous when the pre-sewn stitches are arranged adjacent to each other.
[0061] In some embodiments, the object may include a cover pre-wrap around a steering wheel, the cover being made of leather, artificial leather, or fabric.
[0062] By the teaching provided in the above description and the related drawings, those skilled in the art to which the present disclosure belongs will understand many modifications and other embodiments of the present disclosure given herein. Therefore, it should be understood that the embodiments of the present disclosure are not limited to the specific embodiments of the present disclosure, and modifications and other embodiments are intended to fall within the scope of the present disclosure. In addition, although exemplary embodiments are described in the context of some illustrative combinations of components and / or functions in the above description and the related drawings, it should be appreciated that different combinations of components and / or functions can be provided in alternative embodiments without departing from the scope of the present disclosure. In this regard, for example, it is expected that other combinations of components and / or functions different from those explicitly described above will also fall within the scope of the present disclosure. Although specific terms are used here, they are only used in general and descriptive senses, rather than restrictive.
Claims
1. A robot for sewing an object (290), comprising: a robotic arm (220) configured to hold a needle, the needle being pre-wired, and a controller (210) configured to move the needle, The object (290) includes a flexible outer surface (297) and pre-sewn stitches formed on the outer surface (297), each of the pre-sewn stitches includes a thread segment (292), the thread segment (292) includes a top side (293) and an opposite bottom side (295), the bottom side (295) faces the outer surface (297), and the controller (210) is configured to perform a sewing operation by causing the needle to pass through the thread segment (292) along a path defined between the bottom side (295) of the thread segment (292) and the outer surface (297) of the object (290).
2. The robot according to claim 1, wherein the controller (210) is configured to: Determining a position to be sewn corresponding to the line segment (292) of the pre-sewn stitch; moving the needle to a preparation position at a first lateral side of the thread section (292), the preparation position being offset from the to-be-sewn position by an offset distance; determining a pose of the needle such that a longitudinal axis of the needle is tangent to an outer surface (297) of the object (290) where the path is located; and With the needle in the determined posture, the needle is moved a first distance from the first lateral side of the line segment (292) to the opposite second lateral side of the line segment (292) so that the needle passes over the line segment (292), and the first distance is greater than the offset distance.
3. The robot according to claim 2 further comprises a camera (252) for capturing an image of the object (290), wherein the position to be sewn and the tangent angle of the needle to the outer surface (297) are determined based on the captured image.
4. The robot according to claim 2, wherein the controller (210) is configured to: At the preparation position, the needle is pressed toward the outer surface (297) in a direction perpendicular to the outer surface (297) to deform the outer surface (297) of the object (290).
5. The robot according to claim 4 further comprises a force sensor, which is attached to the robot arm (220) and is used to sense the contact force between the needle and the object (290), wherein a degree of pressing is determined based on the sensed contact force, and the degree of pressing is determined in association with the material of the object (290).
6. The robot according to claim 4, wherein the controller (210) is configured to: While the needle is kept pressed, the needle is linearly moved from the first lateral side of the thread segment (292) by the first distance to reach the opposite second lateral side of the thread segment (292).
7. The robot according to claim 4, wherein the controller (210) is configured to: adjusting the posture of the needle so that the needle tip of the needle is tilted upward away from the outer surface (297) after moving the first distance; and With the adjusted posture, the needle is moved a second distance.
8. The robot according to claim 7, wherein the degree of inclination of the needle tip of the needle is determined so that further movement of the needle tip does not interfere with other pre-sewn stitches.
9. The robot according to any one of claims 1-8, wherein the object (290) comprises a covering (294) pre-wound around a steering wheel, the covering (294) being made of leather, artificial leather or fabric.
10. A method for sewing an object (290), comprising: The needle is held by a robotic arm (220), the needle being pre-wired, and A sewing operation is performed by a controller (210) by causing the needle to pass over the thread segment (292) from the bottom side (295) of the thread segment (292), wherein the object (290) includes a flexible outer surface (297) and pre-sewn stitches formed on the outer surface (297), each of the pre-sewn stitches including the thread segment (292), the thread segment (292) including a top side (293) and an opposite bottom side (295), the bottom side (295) facing the outer surface (297).
11. The method according to claim 10, further comprising Determining, by means of the controller (210), a position to be sewn corresponding to the line segment (292) of the pre-sewn stitch; Moving the needle to a preparation position at a first lateral side of the thread section (292) by the controller (210), the preparation position being offset from the to-be-sewn position by an offset distance; determining, by the controller (210), a posture of the needle such that a longitudinal axis of the needle is tangent to an outer surface (297) on the object (290) located at the line segment (292) through which the needle passes; and When the needle is in the determined posture, the controller (210) moves the needle a first distance from a first lateral side of the thread segment (292) to an opposite second lateral side of the thread segment (292) so that the needle passes through the thread segment (292), and the first distance is greater than the offset distance.
12. The method according to claim 11, further comprising determining the to-be-sewn position and a tangent angle of the needle to the outer surface (297) based on a captured image captured by a camera (252).
13. The method according to claim 11, further comprising: In the prepared position, the needle is pressed toward the outer surface (297) in a direction perpendicular to the outer surface (297) to deform the outer surface (297) of the object (290), and the degree of pressing is determined based on the contact force sensed by a force sensor attached to the robot arm (220).
14. The method according to claim 13, further comprising: While the needle is maintained in the pressed state, the needle is linearly moved from the first lateral side of the thread segment (292) by the first distance to reach the opposite second lateral side of the thread segment (292).
15. The method according to claim 13, further comprising: adjusting the posture of the needle so that the needle tip of the needle is tilted upward away from the outer surface (297) after moving the first distance, wherein the degree of inclination of the needle tip is determined so that further movement of the needle tip does not interfere with other pre-sewn stitches; and With the adjusted posture, the needle is moved a second distance.
16. The method according to any one of claims 10-15, wherein the object (290) comprises a covering (294) pre-wound around a steering wheel, the covering (294) being made of leather, artificial leather or fabric.