Rotatable lower arm for robot sewing assembly
The rotatable lower arm in the robotic sewing assembly addresses the challenge of sewing complex parts by allowing dynamic adjustment and collision avoidance, facilitating efficient sewing of 3D planar components.
Patent Information
- Application Number
- JP2025048166
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-09-19
- Filing Date
- 2025-03-24
- Publication Date
- 2025-10-14
AI Technical Summary
Robotic sewing technologies with fixed-position lower arm posts struggle to sew parts with complex shapes due to potential collisions and limited access, necessitating adjustments or realignments.
A robotic sewing assembly with a rotatable lower arm that can pivot about a horizontal axis, equipped with a motor-driven rotation mechanism, drive trains, and a programmable control system to maintain stitch plate position and avoid collisions, allowing for sewing complex 3D planar parts.
Enables seamless sewing of complex 3D planar parts by dynamically adjusting the lower arm to fit the part's geometry, enhancing sewing efficiency and avoiding collisions.
Smart Images
Figure 2025156071000001_ABST
Abstract
Description
[Background technology]
[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS]
[0002]
[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 571,783, filed March 29, 2024, the disclosure of which is incorporated herein by reference in its entirety. [background]
[0003]
[0002] Exemplary embodiments of the present disclosure relate to the art of robotic sewing assemblies for use in sewing processes.
[0004] Current robotic sewing technology often includes a sewing head with a lower arm post that is fixed in a predetermined position (i.e., a fixed-position lower arm post). Due to the presence of the lower arm post and the fact that the lower arm post is fixed in a predetermined position, the lower arm post often makes it difficult to sew parts with complex shapes. During a sewing operation for a part with a complex shape, the lower arm post may collide with the part itself or otherwise prevent the sewing head from accessing certain portions of the part. In these and other cases, it may be necessary to adjust or realign the sewing head to allow the sewing head to complete the sewing operation.
[0005]
[0004] The hand sewing industry, particularly in the manufacture of footwear, bags and luggage, has used rotary lower arm technology, which is not available in robotic sewing technology.
[0006] overview
[0007] According to one aspect of the present disclosure, a robotic sewing assembly is provided, the robotic sewing assembly including a sewing head body, an upper arm, a motor, and a lower arm. The upper arm is attachable to the sewing head body and includes a sewing needle oriented along a first axis. The lower arm is rotatably attachable to the sewing head body so as to be rotatable by the motor about a second axis defined transversely to the first axis. The lower arm includes a stitch plate, a butterfly looper, and first and second drive trains. The first drive train is extendable through the lower arm and configured to maintain the position of the stitch plate during rotation of the lower arm. The second drive train is extendable through the lower arm and configured to drive the butterfly looper during rotation of the lower arm.
[0008] According to additional and / or alternative embodiments, the upper arm, sewing needle, and lower arm define an empty interior sewing area.
[0009] According to additional and / or alternative embodiments, the lower arm is rotatable 160° about the second axis.
[0010] According to additional and / or alternative embodiments, the lower arm and the first and second drive trains are correspondingly U-shaped.
[0011] According to additional and / or alternative embodiments, at least one of the first drive train and the second drive train includes a concentric shaft.
[0012] According to additional and / or alternative embodiments, the counterweight is disposable to reduce torque requirements on the lower arm.
[0013] According to additional and / or alternative embodiments, the bearing is disposable and supportable on the sewing head body for supporting the lower arm relative to the sewing head body.
[0014]
[0012] According to additional and / or alternative embodiments, wings can extend outward from the sewing head body, and roller bearings can be attached to the lower arm to support the lower arm relative to the wings during rotation of the lower arm.
[0015] According to additional and / or alternative embodiments, a programmable control system is configured to robotically control the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm, the programmable control system including a sensor system for measuring a distance between the lower arm and an article to be sewn, the programmable control system being configured to modify programmed operation of the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm according to readings of the sensor system.
[0016] According to one aspect of the present disclosure, a robotic sewing assembly is provided, the robotic sewing assembly including a sewing head body, an upper arm, a motor, a lower arm rotational drive train, and a lower arm. The upper arm is attachable to the sewing head body and includes a sewing needle oriented along a first axis. The lower arm is rotatably attachable to the sewing head body so as to be rotatable about a second axis defined transversely to the first axis by the motor via the lower arm rotational drive train. The lower arm includes a stitch plate, a butterfly looper, a first drive train, and a second drive train. The first drive train is extendable through the lower arm and configured to maintain the position of the stitch plate during rotation of the lower arm. The second drive train is extendable through the lower arm and configured to drive the butterfly looper during rotation of the lower arm.
[0017] According to additional and / or alternative embodiments, the upper arm, sewing needle, and lower arm define an empty interior sewing area.
[0018] According to additional and / or alternative embodiments, the lower arm is rotatable 160° about the second axis.
[0019] According to additional and / or alternative embodiments, the lower arm and the first and second drive trains are correspondingly U-shaped.
[0020] According to additional and / or alternative embodiments, at least one of the first drive train and the second drive train includes concentric shafts.
[0021] According to additional and / or alternative embodiments, the counterweight is disposable to reduce torque requirements on the lower arm.
[0022] According to additional and / or alternative embodiments, the bearing is supportable and disposable on the sewing head body for supporting the lower arm relative to the sewing head body.
[0023]
[0021] According to additional and / or alternative embodiments, wings can extend outward from the sewing head body, and roller bearings can be attached to the lower arm to support the lower arm relative to the wings during rotation of the lower arm.
[0024] According to additional and / or alternative embodiments, a programmable control system is configured to robotically control the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm. The programmable control system includes a sensor system for measuring a distance between the lower arm and an article to be sewn. The programmable control system is configured to modify programmed operation of the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm according to readings of the sensor system.
[0025] According to one aspect of the present disclosure, there is provided a method of operating a robotic sewing assembly, the method including programming the robotic sewing assembly to perform a sewing operation on an article, and driving the robotic sewing assembly in accordance with the programming, the driving step including operating an upper arm including a sewing needle oriented along a first axis, rotating a lower arm about a second axis defined transverse to the first axis, driving a first drive train extending through the lower arm to maintain a position of a stitch plate of the lower arm during rotation of the lower arm, and driving a second drive train extending through the lower arm to drive a butterfly looper of the lower arm during rotation of the lower arm.
[0026]
[0024] According to further and / or alternative embodiments, the method further includes the steps of sensing the distance between the lower arm and the article, determining whether the distance is less than a predetermined distance, and, if the distance is less than the predetermined distance, modifying the drive of the robotic sewing head in accordance with programming to increase the distance.
[0027]
[0025] Further features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the present disclosure are described in detail herein and are considered part of the claimed technical concept. For a better understanding of the advantages and features of the present disclosure, please refer to the description and drawings. [Brief explanation of the drawings]
[0028] For a more complete understanding of this disclosure, reference is now made to the following brief description taken in conjunction with the accompanying drawings and detailed description, wherein like reference numerals represent like parts. [Figure 1A] FIG. 1A is a perspective view of a robotic sewing assembly including a rotatable lower arm according to an embodiment. [Figure 1B]FIG. 1B is a perspective view of a robotic sewing assembly including a rotatable lower arm according to an embodiment. [Figure 1C] FIG. 1C is a perspective view of a robotic sewing assembly including a rotatable lower arm according to an embodiment. [Figure 2] 2 is an enlarged and partially cut-away perspective view of a portion of the robotic sewing assembly including the rotatable lower arm of FIG. 1 according to an embodiment. [Figure 3A] FIG. 3A is a side view of a sewing needle and stitch plate assembly of the robotic sewing assembly of FIGS. 1 and 2, according to an embodiment. [Figure 3B] FIG. 3B is a side view of a sewing needle and stitch plate assembly of the robotic sewing assembly of FIGS. 1 and 2, according to an embodiment. [Figure 3C] FIG. 3C is a side view of a sewing needle and stitch plate assembly of the robotic sewing assembly of FIGS. 1 and 2, according to an embodiment. [Figure 4] FIG. 4 is a side schematic view of the concentric shafts of the drive train of the robotic sewing assembly of FIGS. 1 and 2, according to an embodiment. [Figure 5] FIG. 5 is a perspective view of a robotic sewing assembly including the rotatable lower arm of FIGS. 1 and 2 and a balance weight according to an embodiment. [Figure 6] FIG. 6 is a perspective view of a robotic sewing assembly including the rotatable lower arm of FIGS. 1 and 2 having bearings and support elements according to an embodiment. [Figure 7] FIG. 7 is a perspective view of a robotic sewing assembly including the rotatable lower arm of FIGS. 1 and 2 having wings and roller bearings, according to an embodiment. [Figure 8] FIG. 8 is a schematic diagram of a robotic sewing assembly, programmable control system, and sensor system according to an embodiment. [Figure 9] FIG. 9 is a flow diagram illustrating a method of operating a robotic sewing assembly according to an embodiment.
[0029] Detailed Description
[0030]
[0036] A detailed description of one or more embodiments of the disclosed apparatus and methods is presented herein by way of example and not limitation with reference to the drawings in which:
[0031]
[0037] The present disclosure provides the ability to sew complex 3D planar parts using a robotic sewing cell, as opposed to robotic sewing techniques that include sewing heads with fixed-position lower arm posts. While robotic sewing heads with fixed-position posts may be limited in their ability to sew parts with complex geometries, the present disclosure provides a robotic sewing assembly with a lower arm that can rotate about a horizontal axis. The rotatable lower arm allows the lower arm to actively sew the part while rotating about the horizontal axis, while maintaining the position of the stitch plate relative to the upper portion of the sewing head. Thus, as the part is being sewn, the lower arm can be manipulated and repositioned to optimize the sewing head to fit the part's geometry. The complex 3D planar part may be an instrument panel (IP) for a vehicle.
[0032]
[0038] 1A, 1B, 1C, and 2, a robotic sewing assembly 101 is provided, which includes a sewing head body 110, an upper arm 120 attached to the sewing head body 110 and including a sewing needle 121 oriented along a first axis A1 and a leg 122 from which the sewing needle 121 extends, a motor 130, a lower arm rotation drive train 140, and a lower arm 150. The lower arm 150 is rotatably attached to the sewing head body 110 so as to rotate about a second axis A2. The second axis A2 is defined transversely or perpendicularly to the first axis A1. Rotation of the lower arm 150 is drivable by the motor 130 via the lower arm rotation drive train 140.
[0033]
[0039] The lower arm rotation drive train 140 includes a motor 130, a pair of a spur gear 141 and a pinion gear 142, and a right-angle gearbox 143. The motor 130 drives the right-angle gearbox 143, which in turn drives the spur gear 141 via the pinion gear 142. The spur gear 141 is fixed to the lower arm 150, and the spur gear 141 is driven by the pinion gear 142, causing the lower arm 150 to rotate about the second axis A2. The lower arm 150 is attached to a horizontal intermediate shaft 144 that protrudes from a post portion 145 of the sewing head body 110. The lower arm 150 can be mounted on a sleeve bearing so that the lower arm 150 is supported by the horizontal intermediate shaft 144 but does not move as the horizontal intermediate shaft 144 rotates.
[0034]
[0040] According to an embodiment, the horizontal intermediate shaft 144 may have a diameter of 16 mm or greater to improve the integrity and rigidity of the mechanism.
[0035]
[0041] The lower arm 150 includes a stitch plate 160, a butterfly looper 170, a first drive train 180, and a second drive train 190. The first drive train 180 is extendable through the interior of the lower arm 150 and is configured to maintain the position of the stitch plate 160 relative to the sewing needle 121 during rotation of the lower arm 150. The second drive train 190 is extendable through the interior of the lower arm 150 and is configured to drive the butterfly looper 170 during rotation of the lower arm 150.
[0036]
[0042] According to an embodiment, the lower arm 150, first drive train 180, and second drive train 190 may be correspondingly U-shaped. In this manner, the upper arm 120, sewing needle 121, legs 122, and lower arm 150 cooperate to define a substantially empty interior sewing area 201. This substantially empty interior sewing area 201 provides ample space to accommodate portions of an article, such as an IP, to be sewn. The rotatability of the lower arm 150 effectively increases the size and usability of the substantially empty interior sewing area 201 by allowing the lower arm 150 to be moved out of the way of the article during a particular sewing operation.
[0037]
[0043] The stitch plate 160 is free-floating on the horizontal shaft. The first drive train 180 includes a bevel gear 181, a set of interconnected shafts 182, and a connecting gear 183 disposed below the stitch plate 160 and to which the set of interconnected shafts 182 is connected. The bevel gear 181 is fixed to the sewing head body 110. As the lower arm 150 rotates about the horizontal intermediate shaft 144, the bevel gear 181 drives the set of interconnected shafts 182, which in turn drives the connecting gear 183. As the lower arm 150 and the set of interconnected shafts 182 rotate, the connecting gear 183 can be driven at a 1:1 ratio relative to the lower arm 150. Thus, as the lower arm 150 rotates, the stitch plate 160 rotates relative to the lower arm 150 and maintains its rotational position relative to the sewing needle 121 , the legs 122 , and the remainder of the sewing head body 110 .
[0038]
[0044] 1A, 1B, and 1C, the lower arm 150 can rotate up to 160 degrees or more about the second axis A2. That is, the lower arm 150 can rotate up to 80 degrees or more clockwise about the second axis A2 from a central position (see FIG. 1B), and the lower arm 150 can rotate up to 80 degrees or more counterclockwise about the second axis A2 from a central position (see FIG. 1C).
[0039]
[0045] The butterfly looper 170 may be a butterfly-type looper that moves through a continuous rotational motion, as opposed to the traditional sickle looper and lockstitch mechanism often used in most robotic sewing heads. The butterfly looper 170 was chosen over a lockstitch mechanism due to its compact packaging, ease of integration into the lower arm 150, and the advantages of using a chain stitch over a lockstitch.
[0040]
[0046] 2 and further referring to FIGS. 3A, 3B, and 3C, a second drive train 190 drives the butterfly looper 170 and is mounted on the horizontal intermediate shaft 144 and connected to a bevel gear 191. The second drive train 190 includes a set of interconnected bevel shafts 192 driven by the bevel gear 191, a pulley 193, a belt 194 that transfers rotation from the set of interconnected bevel shafts 192 to the pulley 193, a stitch plate support, a pulley casing 1945, and a gear 195. The butterfly looper 170 is driven from the pulley 193, which is driven by the belt 194. The butterfly looper 170 is supported by the stitch plate 160, which maintains its rotational position relative to the sewing needle 121, the legs 122, and the rest of the sewing head body 110, via the gear 195. Stitch plate 160 is mounted to lower arm 150 by structural components 196 that include bearings 197 that allow polyaxial constrained rotation of stitch plate 160. Sheet metal shield 198 prevents material from contacting pulley 193.
[0041]
[0047] 4, according to an embodiment, at least one of the first drive train 180 and the second drive train 190 may include concentric shafts 401 to reduce spatial requirements. That is, for the first drive train 180, at least a portion of the set of interconnected shafts 182 may include or be provided as concentric shafts 401, and for the second drive train 190, at least a portion of the set of interconnected bevel shafts 192 may include or be provided as concentric shafts 720.
[0042]
[0048] 5, according to an embodiment, robotic sewing assembly 101 may further include a counterweight 501 (motor 130 has been removed for clarity). Counterweight 501 may be disposed on lower arm 150 and configured to effectively reduce torque requirements associated with rotation of lower arm 150. Counterweight 501 may be oriented so as not to encroach on substantially empty interior sewing area 201 or to limit encroachment into substantially empty interior sewing area 201 to a practical extent.
[0043]
[0049] 6 , according to an embodiment, the robotic sewing assembly 101 may further include a bearing 601 having a support element 602 supportably positionable on the sewing head body 110 to support the lower arm 150 relative to the sewing head body 110. The bearing 601 and support element 602 enable rotation of the lower arm 150 and may be positioned about the horizontal intermediate shaft 144. In this configuration, the bearing element 601 and support element 602 effectively replace the reliability of the lower arm 150 being mounted on the horizontal intermediate shaft 144.
[0044]
[0050] Referring to FIG. 7 , according to an embodiment, the robotic sewing assembly 101 may further include wings 701 extending outward in opposite directions from the sewing head body 110 to define a support plane for rotation of the lower arm 150 and a roller bearing 702. The roller bearing 702 may be attachable to the lower arm 150 and provide support for the lower arm 150 relative to the wings 701 during rotation of the lower arm 150. The rotational length of the wings 701 may be at least sufficient to support the full rotational capability of the lower arm 150. Thus, if the lower arm 150 is rotatable clockwise about the second axis A2 by 80 degrees or more from a center position, one wing 701 extends a sufficient length to support the entire clockwise rotation of the lower arm 150, and if the lower arm 150 is rotatable counterclockwise about the second axis A2 by 80 degrees or more from a center position, the other wing 701 extends a sufficient length to support the entire counterclockwise rotation of the lower arm 150.
[0045]
[0051] 8 , robotic sewing assembly 101 may include a programmable control system 801, which may include a sensor system 802. Programmable control system 801 may include a processing unit and a memory for storing executable instructions readable and executable by the processing unit, whereby the processing unit controls the operation of robotic sewing assembly 101 according to readings of sensor system 802, and may include an input / output (I / O) unit through which the processing unit communicates with robotic sewing assembly 101 and sensor system 802. Thus, programmable control system 801 may be configured to robotically control the operation of sewing head body 110, upper arm 120, sewing needle 121, lower arm 150, the rotation of lower arm 150, and each of first drive train 180 and second drive train 190 without operator involvement. Sensor system 802 may be configured to measure the distance between lower arm 150 and an article being sewn. The programmable control system 801 can be further configured to modify the programmed operation of the sewing head body 110, the upper arm 120, the sewing needle 121, the lower arm 150, the rotation of the lower arm 150, and the respective operation of the first drive train 180 and the second drive train 190 according to readings from the sensor system 802. For example, to the extent that the size, shape, and / or configuration of the article being sewn deviates from a nominal size, shape, and / or configuration that poses a risk of a portion of the robotic sewing assembly 101 colliding with the article during sewing, the sensor system 802 can detect the potential collision, and the programmable control system 801, upon being alerted to the potential collision by the sensor system 802, can modify its programmed operation to avoid the potential collision.
[0046]
[0052] While the various embodiments described above have been described separately, it should be understood that they can be combined together in various combinations. Furthermore, it should be understood that other configurations than those described above are possible. For example, motor 130 and lower arm rotary drive train 140 could be replaced by a motor driving roller bearing 702 in FIG. 7, which would allow corresponding modifications to first drive train 180 and second drive train 190.
[0047]
[0053] 9, a method 900 of operating a robotic sewing assembly, such as the robotic sewing assembly 101 described above, is provided. As shown in FIG. 9, method 900 can include programming the robotic sewing assembly to perform a sewing operation on an article (block 901) and driving the robotic sewing assembly in accordance with the programming (block 902). The driving step of block 902 can include operating an upper arm including a sewing needle oriented along a first axis (block 9021), rotating a lower arm about a second axis defined transverse to the first axis (block 9022), driving a first drive train extending through the lower arm to maintain a position of a stitch plate of the lower arm during rotation of the lower arm (block 9023), and driving a second drive train extending through the lower arm to drive a looper of the lower arm during rotation of the lower arm (block 9024). According to a further embodiment, the method 900 may further include the steps of sensing the distance between the lower arm and the article (block 903), determining whether the distance is less than a predetermined distance such that there is a risk of a possible impact as described above (block 904), and if the distance is less than the predetermined distance, modifying the actuation of block 902 according to programming to increase the distance (block 905).
[0048]
[0054] A technical effect and advantage of the present disclosure is the provision of a robotic sewing assembly capable of sewing complex 3D planar parts. The robotic sewing assembly has a rotatable lower arm that allows the lower arm to rotate while maintaining the position of the stitch plate relative to an upper portion of the sewing assembly and while actively sewing the part. Thus, as the part is being sewn, the lower arm may be manipulated and repositioned to optimize the sewing assembly to fit the geometry of the part.
[0049]
[0055] The term "about" is intended to include the degree of error associated with measurement of a particular quantity based on equipment available at the time of filing. For example, "about" can include a range of ±8%, 5%, or 2% of a given value.
[0050]
[0056] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly dictates otherwise. It is further understood that the terms "comprises" and / or "comprising," when used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.
[0051]
[0057] While the present disclosure has been described with reference to one or more exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its essential scope. Therefore, it is not intended that the disclosure be limited to the particular embodiment disclosed as the best mode contemplated for carrying out the disclosure, but rather that the disclosure is intended to include all embodiments falling within the scope of the appended claims.
Claims
1. 1. A robotic sewing assembly comprising: A sewing head body, an upper arm attachable to the sewing head body and including a sewing needle oriented along a first axis; A motor; a lower arm rotatably mounted to the sewing head body by the motor and rotatable about a second axis defined transversely to the first axis; The lower arm comprises: Stitch plate and Butterfly Looper and a first drive train extendable through the lower arm and configured to maintain the position of the stitch plate during rotation of the lower arm; a second drive train extendable through the lower arm and configured to drive the butterfly looper during rotation of the lower arm; 1. A robotic sewing assembly comprising:
2. The robotic sewing assembly of claim 1 , wherein the upper arm, the sewing needle, and the lower arm define an empty interior sewing area.
3. The robotic sewing assembly of claim 1 , wherein the lower arm is rotatable 160° about the second axis.
4. 2. The robotic sewing assembly of claim 1, wherein the lower arm and the first and second drive trains are correspondingly U-shaped.
5. The robotic sewing assembly of claim 1 , wherein at least one of the first drive train and the second drive train comprises concentric shafts.
6. The robotic sewing assembly of claim 1 , further comprising a disposable counterweight to reduce torque demands on the lower arm.
7. The robotic sewing assembly of claim 1 , further comprising a supportive disposable bearing on the sewing head body for supporting a lower arm relative to the sewing head body.
8. wings extendable outwardly from the sewing head body; a roller bearing mountable to the lower arm for supporting the lower arm relative to the wing during rotation of the lower arm; The robotic sewing assembly of claim 1 further comprising:
9. 10. A robotic sewing assembly, further comprising: a programmable control system configured to robotically control the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm, the programmable control system includes a sensor system for measuring the distance between the lower arm and an article to be sewn; 2. The robotic sewing assembly of claim 1, wherein the programmable control system is configured to modify programmed movements of the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm according to readings of the sensor system.
10. 1. A robotic sewing assembly comprising: A sewing head body, an upper arm attachable to the sewing head body and including a sewing needle oriented along a first axis; A motor; a lower arm rotation drive train; a lower arm rotatably attached to the sewing head body so as to be rotatable by the motor via the lower arm rotation drive train about a second axis defined transversely to the first axis; The lower arm comprises: Stitch plate and Butterfly Looper and a first drive train extendable through the lower arm and configured to maintain the position of the stitch plate during rotation of the lower arm; a second drive train extendable through the lower arm and configured to drive the butterfly looper during rotation of the lower arm; 1. A robotic sewing assembly comprising:
11. The robotic sewing assembly of claim 10 , wherein the upper arm, the sewing needle, and the lower arm define an empty interior sewing area.
12. The robotic sewing assembly of claim 10 , wherein the lower arm is rotatable 160° about the second axis.
13. The robotic sewing assembly of claim 10 , wherein the lower arm and the first and second drive trains are correspondingly U-shaped.
14. The robotic sewing assembly of claim 10 , wherein at least one of the first drive train and the second drive train comprises concentric shafts.
15. The robotic sewing assembly of claim 10 , further comprising a disposable counterweight to reduce torque demands on the lower arm.
16. The robotic sewing assembly of claim 10, further comprising a supportive disposable bearing on the sewing head body for supporting a lower arm relative to the sewing head body.
17. wings extendable outwardly from the sewing head body; a roller bearing mountable to the lower arm for supporting the lower arm relative to the wing during rotation of the lower arm; The robotic sewing assembly of claim 10 further comprising:
18. 10. A robotic sewing assembly, further comprising: a programmable control system configured to robotically control the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm, the programmable control system includes a sensor system for measuring the distance between the lower arm and an article to be sewn; 11. The robotic sewing assembly of claim 10, wherein the programmable control system is configured to modify programmed movements of the sewing head body, the upper arm, the lower arm, and the rotation of the lower arm according to readings of the sensor system.
19. 1. A method of operating a robotic sewing assembly, comprising: programming a robotic sewing assembly to perform a sewing operation on the article; driving the robotic sewing assembly in accordance with the program; operating an upper arm with a sewing needle oriented along a first axis; rotating the lower arm about a second axis defined transversely to the first axis; driving a first drive train extending through the lower arm to maintain the position of a stitch plate on the lower arm during rotation of the lower arm; driving a second drive train extending through the lower arm during rotation of the lower arm to drive a butterfly looper of the lower arm; and A method comprising:
20. sensing a distance between the lower arm and the article; determining whether the distance is less than a predetermined distance; if the distance is less than the predetermined distance, modifying the drive of the robotic sewing head in accordance with the program to increase the distance; 20. The method of claim 19 further comprising: