FIELD

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application No. 62/903,356, fded on September 20, 2019, the content of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates generally to methods for forming a glass ribbon and, more particularly, to methods for forming a glass ribbon with a glass manufacturing apparatus comprising a control assembly.

BACKGROUND

[0003] It is known to manufacture molten material into a glass ribbon with a glass manufacturing apparatus. Sometimes, when there is contact with the glass ribbon, there is potential for damage to the glass ribbon. To limit damage, an end effector can engage the glass ribbon. However, matching a speed and travel path of the end effector to the glass ribbon can be difficult.

SUMMARY

[0004] The following presents a simplified summary of the disclosure to provide a basic understanding of some embodiments described in the detailed description.

[0005] In some embodiments, the glass manufacturing apparatus comprises one or more devices that facilitate reducing relative motion between the glass ribbon and an end effector. For example, the end effector can engage the glass ribbon and move in a travel direction with the glass ribbon. The end effector can be coupled to a sensor, which can sense any forces imparted upon the end effector by the glass ribbon. A control assembly can be electrically connected to the sensor and to a robot arm that controls movement of the end effector. The control assembly can receive force data from the sensor, and adjust a speed and/or a path of the end effector to more closely match a speed and/or a path of the glass ribbon. Consequently, relative motion between the glass ribbon and the end effector can be reduced, thus reducing any forces imparted upon the glass ribbon.

[0006] In accordance with some embodiments, methods for forming a glass ribbon comprises moving the glass ribbon along a travel path in a travel direction at a ribbon velocity. Methods comprise engaging the glass ribbon with an end effector attached to a robot arm. Methods comprise moving the end effector at a first robot velocity in the travel direction. Methods comprise sensing a force exerted by the glass ribbon upon the end effector. Methods comprise changing a speed of the end effector from the first robot velocity to a second robot velocity when a magnitude of the force exceeds a predetermined value.

[0007] In some embodiments, methods comprise separating a first ribbon portion of the glass ribbon from a second ribbon portion of the glass ribbon prior to changing the speed.

[0008] In some embodiments, methods comprise engaging the second ribbon portion of the glass ribbon prior to changing the speed.

[0009] In some embodiments, methods comprise maintaining the speed of the end effector at the first robot velocity during a time period from the engaging the first ribbon portion with the end effector to the separating of the first ribbon portion from the second ribbon portion.

[0010] In some embodiments, the force is sensed at a plurality of locations.

[0011] In accordance with some embodiments, methods for forming a glass ribbon comprise moving the glass ribbon along a travel path in a travel direction. Methods comprise engaging a first ribbon portion of the glass ribbon with an end effector attached to a robot arm. Methods comprise moving the end effector at a first robot velocity in the travel direction during a first operational cycle during a time period from the engaging of the first ribbon portion with the end effector to a separation of the first ribbon portion from a second ribbon portion of the glass ribbon. Methods comprise sensing a first force exerted by the first ribbon portion upon the end effector during the first operational cycle. Methods comprise engaging the second ribbon portion with the end effector following the first operational cycle. Methods comprise changing a speed of the end effector from the first robot velocity to a second robot velocity based on the first force and moving the end effector at the second robot velocity in the travel direction during a second operational cycle.

[0012] In some embodiments, methods comprise separating the first ribbon portion from the second ribbon portion prior to engaging the second ribbon portion.

[0013] In some embodiments, methods comprise sensing a second force exerted by the second ribbon portion upon the end effector during the second operational cycle. Methods comprise engaging a third ribbon portion of the glass ribbon with the end effector following the second operational cycle. Methods comprise changing the speed of the end effector from the second robot velocity to a third robot velocity based on one or more of the first force or the second force and moving the end effector at the third robot velocity in the travel direction during a third operational cycle.

[0014] In some embodiments, methods comprise maintaining the speed of the end effector at the first robot velocity throughout the first operational cycle during a time period from the engaging the first ribbon portion with the end effector to the separating of the first ribbon portion from the second ribbon portion.

[0015] In some embodiments, methods comprise separating the second ribbon portion from the third ribbon portion prior to engaging the third ribbon portion.

[0016] In some embodiments, methods comprise maintaining the speed of the end effector at the second robot velocity throughout the second operational cycle during a time period from the engaging the second ribbon portion with the end effector to the separating of the second ribbon portion from the third ribbon portion.

[0017] In some embodiments, the first force is sensed at a plurality of locations.

[0018] In some embodiments, the changing the speed occurs when a magnitude of the first force exceeds a predetermined value.

[0019] In some embodiments, the speed of the end effector is changed to the second robot velocity prior to the start of the second operational cycle.

[0020] In accordance with some embodiments, methods for forming a glass ribbon comprise moving the glass ribbon along a travel path in a travel direction at a ribbon velocity. Methods comprise engaging a first ribbon portion of the glass ribbon with an end effector attached to a robot arm. Methods comprise moving the end effector at a robot velocity in the travel direction. Methods comprise sensing a force exerted by the first ribbon portion upon the end effector. Methods comprise quantifying the ribbon velocity by correlating the ribbon velocity to the robot velocity when a magnitude of the force is within a predetermined value. Methods comprise adjusting a parameter of the glass ribbon based on the ribbon velocity.

[0021] In some embodiments, quantifying the ribbon velocity comprises determining an average ribbon velocity during a time period from the engaging the first ribbon portion with the end effector to a separation of the first ribbon portion from a second ribbon portion of the glass ribbon.

[0022] In some embodiments, the adjusting the parameter comprises maintaining a constant length of the first ribbon portion and the second ribbon portion.

[0023] In some embodiments, the quantifying the ribbon velocity comprises determining an instantaneous ribbon velocity during a sampling period that is less than about 2 milliseconds.

[0024] Additional features and advantages of the embodiments disclosed herein will be set forth in the detailed description that follows, and in part will be clear to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings. It is to be understood that both the foregoing general description and the following detailed description present embodiments intended to provide an overview or framework for understanding the nature and character of the embodiments disclosed herein. The accompanying drawings are included to provide further understanding and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure, and together with the description explain the principles and operations thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] These and other features, embodiments and advantages are better understood when the following detailed description is read with reference to the accompanying drawings, in which:

[0026] FIG. 1 schematically illustrates example embodiments of a glass manufacturing apparatus in accordance with embodiments of the disclosure; [0027] FIG. 2 illustrates a perspective cross-sectional view of the glass manufacturing apparatus along line 2-2 of FIG. 1 in accordance with embodiments of the disclosure;

[0028] FIG. 3 illustrates an enlarged portion of the glass manufacturing apparatus taken at view 3 of FIG. 1 in accordance with embodiments of the disclosure;

[0029] FIG. 4 illustrates a side view of the glass manufacturing apparatus comprising an end effector along line 4-4 of FIG. 3 in accordance with embodiments of the disclosure;

[0030] FIG. 5 illustrates a side view of the glass manufacturing apparatus similar to FIG. 4 with the end effector engaging a glass ribbon in accordance with embodiments of the disclosure;

[0031] FIG. 6 illustrates a side view of the glass manufacturing apparatus similar to FIG. 5 with a first ribbon portion being separated in accordance with embodiments of the disclosure;

[0032] FIG. 7 illustrates a side view of the glass manufacturing apparatus similar to FIG. 6 with the first ribbon portion being separated from a second ribbon portion in accordance with embodiments of the disclosure;

[0033] FIG. 8 illustrates a side view of the glass manufacturing apparatus similar to FIG. 7 with the end effector engaging the second ribbon portion in accordance with embodiments of the disclosure;

[0034] FIG. 9 illustrates a side view of the glass manufacturing apparatus similar to FIG. 8 with the end effector separating the second ribbon portion from a third ribbon portion in accordance with embodiments of the disclosure;

[0035] FIG. 10 illustrates a side view of the glass manufacturing apparatus similar to FIG. 9 with the end effector engaging the third ribbon portion of the glass ribbon following the second operational cycle;

[0036] FIG. 11 illustrates a control diagram of the glass manufacturing apparatus in accordance with embodiments of the disclosure; and

[0037] FIG. 12 illustrates a plot of time and a force exerted upon an end effector by the glass ribbon in accordance with embodiments of the disclosure. DETAILED DESCRIPTION

[0038] Embodiments will now be described more fully hereinafter with reference to the accompanying drawings in which example embodiments are shown. Whenever possible, the same reference numerals are used throughout the drawings to refer to the same or like parts. However, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0039] The present disclosure relates to a glass manufacturing apparatus and methods for forming a glass ribbon. For purposes of this application, “glass ribbon” is considered one or more of a glass ribbon in a viscous state, a glass ribbon in an elastic state (e.g., at room temperature) and/or a glass ribbon in a viscoelastic state between the viscous state and the elastic state. Methods and apparatus for forming a glass ribbon will now be described by way of example embodiments for producing the glass ribbon. As schematically illustrated in FIG. 1, in some embodiments, an exemplary glass manufacturing apparatus 100 can comprise a glass melting and delivery apparatus 102 and a forming apparatus 101 comprising a forming vessel 140 designed to produce a glass ribbon, for example, a glass ribbon 103 from a quantity of molten material 121. In some embodiments, the glass ribbon 103 can comprise a central portion 152 positioned between opposite edge portions (e.g., edge beads) formed along a first outer edge 153 and a second outer edge 155 of the glass ribbon 103, wherein a thickness of the edge portions can be greater than a thickness of the central portion. Additionally, in some embodiments, a separated glass ribbon 104 can be separated from the glass ribbon 103 along a separation path 151 by a glass separator 149 (e.g., scribe, score wheel, diamond tip, laser, etc.).

[0040] In some embodiments, the glass melting and delivery apparatus 102 can comprise a melting vessel 105 oriented to receive batch material 107 from a storage bin 109. The batch material 107 can be introduced by a batch delivery device 111 powered by a motor 113. In some embodiments, an optional controller 115 can be operated to activate the motor 113 to introduce a desired amount of batch material 107 into the melting vessel 105, as indicated by arrow 117. The melting vessel 105 can heat the batch material 107 to provide molten material 121. In some embodiments, a melt probe 119 can be employed to measure a level of molten material 121 within a standpipe 123 and communicate the measured information to the controller 115 by way of a communication line 125. [0041] Additionally, in some embodiments, the glass melting and delivery apparatus 102 can comprise a first conditioning station comprising a fining vessel 127 located downstream from the melting vessel 105 and coupled to the melting vessel 105 by way of a first connecting conduit 129. In some embodiments, molten material 121 can be gravity fed from the melting vessel 105 to the fining vessel 127 by way of the first connecting conduit 129. For example, in some embodiments, gravity can drive the molten material 121 through an interior pathway of the first connecting conduit 129 from the melting vessel 105 to the fining vessel 127. Additionally, in some embodiments, bubbles can be removed from the molten material 121 within the fining vessel 127 by various techniques.

[0042] In some embodiments, the glass melting and delivery apparatus 102 can further comprise a second conditioning station comprising a mixing chamber 131 that can be located downstream from the fining vessel 127. The mixing chamber 131 can be employed to provide a homogenous composition of molten material 121, thereby reducing or eliminating inhomogeneity that may otherwise exist within the molten material 121 exiting the fining vessel 127. As shown, the fining vessel 127 can be coupled to the mixing chamber 131 by way of a second connecting conduit 135. In some embodiments, molten material 121 can be gravity fed from the fining vessel 127 to the mixing chamber 131 by way of the second connecting conduit 135. For example, in some embodiments, gravity can drive the molten material 121 through an interior pathway of the second connecting conduit 135 from the fining vessel 127 to the mixing chamber 131.

[0043] Additionally, in some embodiments, the glass melting and delivery apparatus 102 can comprise a third conditioning station comprising a delivery chamber 133 that can be located downstream from the mixing chamber 131. In some embodiments, the delivery chamber 133 can condition the molten material 121 to be fed into an inlet conduit 141. For example, the delivery chamber 133 can function as an accumulator and/or flow controller to adjust and provide a consistent flow of molten material 121 to the inlet conduit 141. As shown, the mixing chamber 131 can be coupled to the delivery chamber 133 by way of a third connecting conduit 137. In some embodiments, molten material 121 can be gravity fed from the mixing chamber 131 to the delivery chamber 133 by way of the third connecting conduit 137. For example, in some embodiments, gravity can drive the molten material 121 through an interior pathway of the third connecting conduit 137 from the mixing chamber 131 to the delivery chamber 133. As further illustrated, in some embodiments, a delivery pipe 139 can be positioned to deliver molten material 121 to forming apparatus 101, for example the inlet conduit 141 of the forming vessel 140.

[0044] Forming apparatus 101 can comprise various embodiments of forming vessels in accordance with features of the disclosure, for example, a forming vessel with a wedge for fusion drawing the glass ribbon, a forming vessel with a slot to slot draw the glass ribbon, or a forming vessel provided with press rolls to press roll the glass ribbon from the forming vessel. In some embodiments, the forming apparatus 101 can comprise a sheet redraw, for example, with the forming apparatus 101 as part of a redraw process. For example, the glass ribbon 104, which can comprise a thickness, may be heated up and redrawn to achieve a thinner glass ribbon 104 comprising a smaller thickness. By way of illustration, the forming vessel 140 shown and disclosed below can be provided to fusion draw molten material 121 off a bottom edge, defined as a root 145, of a forming wedge 209 to produce the glass ribbon 103. For example, in some embodiments, the molten material 121 can be delivered from the inlet conduit 141 to the forming vessel 140. The molten material 121 can then be formed into the glass ribbon 103 based, in part, on the structure of the forming vessel 140. For example, as shown, the molten material 121 can be drawn off the bottom edge (e.g., root 145) of the forming vessel 140 along a draw path extending in a travel direction 154 of the glass manufacturing apparatus 100. In some embodiments, edge directors 163, 164 can direct the molten material 121 off the forming vessel 140 and define, in part, a width “W” of the glass ribbon 103. In some embodiments, the width “W” of the glass ribbon 103 extends between the first outer edge 153 of the glass ribbon 103 and the second outer edge 155 of the glass ribbon 103. In some embodiments, a pulling roll assembly 158 can aid in drawing the glass ribbon 103 downwardly along the travel direction 154 away from the root 145. The pulling roll assembly 158 can comprise one or more pulling rolls that may be driven, for example, by motors.

[0045] In some embodiments, the width “W” of the glass ribbon 103, which extends between the first outer edge 153 of the glass ribbon 103 and the second outer edge 155 of the glass ribbon 103, can be greater than or equal to about 20 millimeters (mm), for example, greater than or equal to about 50 mm, for example, greater than or equal to about 100 mm, for example, greater than or equal to about 500 mm, for example, greater than or equal to about 1000 mm, for example, greater than or equal to about 2000 mm, for example, greater than or equal to about 3000 mm, for example, greater than or equal to about 4000 mm, although other widths less than or greater than the widths mentioned above can be provided in further embodiments. For example, in some embodiments, the width “W” of the glass ribbon 103 can be within a range from about 20 mm to about 4000 mm, for example, within a range from about 50 mm to about 4000 mm, for example, within a range from about 100 mm to about 4000 mm, for example, within a range from about 500 mm to about 4000 mm, for example, within a range from about 1000 mm to about 4000 mm, for example, within a range from about 2000 mm to about 4000 mm, for example, within a range from about 3000 mm to about 4000 mm, for example, within a range from about 20 mm to about 3000 mm, for example, within a range from about 50 mm to about 3000 mm, for example, within a range from about 100 mm to about 3000 mm, for example, within a range from about 500 mm to about 3000 mm, for example, within a range from about 1000 mm to about 3000 mm, for example, within a range from about 2000 mm to about 3000 mm, for example, within a range from about 2000 mm to about 2500 mm, and all ranges and subranges therebetween.

[0046] FIG. 2 shows a cross-sectional perspective view of the forming apparatus

101 (e.g., forming vessel 140) along line 2-2 of FIG. 1. In some embodiments, the forming vessel 140 can comprise a trough 201 oriented to receive the molten material 121 from the inlet conduit 141. For illustrative purposes, cross-hatching of the molten material 121 is removed from FIG. 2 for clarity. The forming vessel 140 can further comprise the forming wedge 209 comprising a pair of downwardly inclined converging surface portions 207, 208 extending between opposed ends 210, 211 (See FIG. 1) of the forming wedge 209. The pair of downwardly inclined converging surface portions 207, 208 of the forming wedge 209 can converge along the travel direction 154 to intersect along the root 145 of the forming vessel 140. A draw plane 213 of the glass manufacturing apparatus 100 can extend through the root 145 along the travel direction 154. In some embodiments, the glass ribbon 103 can be drawn in the travel direction 154 along the draw plane 213. As shown, the draw plane 213 can bisect the forming wedge 209 through the root 145 although, in some embodiments, the draw plane 213 can extend at other orientations relative to the root 145. In some embodiments, the glass ribbon 103 can move along a travel path 221 that may be co-planar with the draw plane 213 in the travel direction 154.

[0047] Additionally, in some embodiments, the molten material 121 can flow in a direction 156 into and along the trough 201 of the forming vessel 140. The molten material 121 can then overflow from the trough 201 by simultaneously flowing over corresponding weirs 203, 204 and downward over the outer surfaces 205, 206 of the corresponding weirs 203, 204. Respective streams of molten material 121 can then flow along the downwardly inclined converging surface portions 207, 208 of the forming wedge 209 to be drawn off the root 145 of the forming vessel 140, where the flows converge and fuse into the glass ribbon 103. The glass ribbon 103 can then be drawn off the root 145 in the draw plane 213 along the travel direction 154. In some embodiments, the glass ribbon 103 comprises one or more states of material based on a vertical location of the glass ribbon 103. For example, at one location, the glass ribbon 103 can comprise the viscous molten material 121, and at another location, the glass ribbon 103 can comprise an amorphous solid in a glassy state (e.g., a glass ribbon).

[0048] The glass ribbon 103 comprises a first major surface 215 and a second major surface 216 facing opposite directions and defining a thickness “T” (e.g., average thickness) of the glass ribbon 103. In some embodiments, the thickness “T’ of the glass ribbon 103 can be less than or equal to about 2 millimeters (mm), less than or equal to about 1 millimeter, less than or equal to about 0.5 millimeters, for example, less than or equal to about 300 micrometers (pm), less than or equal to about 200 micrometers, or less than or equal to about 100 micrometers, although other thicknesses may be provided in further embodiments. For example, in some embodiments, the thickness “T’ of the glass ribbon 103 can be within a range from about 20 micrometers to about 200 micrometers, within a range from about 50 micrometers to about 750 micrometers, within a range from about 100 micrometers to about 700 micrometers, within a range from about 200 micrometers to about 600 micrometers, within a range from about 300 micrometers to about 500 micrometers, within a range from about 50 micrometers to about 500 micrometers, within a range from about 50 micrometers to about 700 micrometers, within a range from about 50 micrometers to about 600 micrometers, within a range from about 50 micrometers to about 500 micrometers, within a range from about 50 micrometers to about 400 micrometers, within a range from about 50 micrometers to about 300 micrometers, within a range from about 50 micrometers to about 200 micrometers, within a range from about 50 micrometers to about 100 micrometers, within a range from about 25 micrometers to about 125 micrometers, comprising all ranges and subranges of thicknesses therebetween. In addition, the glass ribbon 103 can comprise a variety of compositions, for example, borosilicate glass, alumino-borosilicate glass, alkali-containing glass, or alkali-free glass, alkali aluminosilicate glass, alkaline earth aluminosilicate glass, soda-lime glass, etc.

[0049] In some embodiments, the glass separator 149 (see FIG. 1) can then separate the glass ribbon 104 from the glass ribbon 103 along the separation path 151 to provide a plurality of separated glass ribbons 104 (i.e., a plurality of sheets of glass). According to other embodiments, a longer portion of the glass ribbon 104 may be coiled onto a storage roll. The separated glass ribbon can then be processed into a desired application, e.g., a display application. For example, the separated glass ribbon can be used in a wide range of display applications, comprising liquid crystal displays (LCDs), electrophoretic displays (EPD), organic light emitting diode displays (OLEDs), plasma display panels (PDPs), touch sensors, photovoltaics, and other electronic displays.

[0050] Referring to FIG. 3, an example of the glass manufacturing apparatus 100 taken at view 3 of FIG. 1 is illustrated. In some embodiments, methods for forming the glass ribbon 103 can comprise moving the glass ribbon 103 along the travel path 221 in the travel direction 154 at a ribbon velocity. In some embodiments, the travel direction 154 may be substantially parallel to the y-axis. In some embodiments, the travel path 221, and the glass ribbon 103, may be substantially parallel to the x-axis and the y-axis, while the travel path 221 and the glass ribbon 103 may be substantially perpendicular to the z-axis. In some embodiments, the glass manufacturing apparatus 100 can comprise a robot assembly 301. The robot assembly 301 can comprise a robot arm 303 and one or more end effectors 305. In some embodiments, the one or more end effectors 305 can be attached to the robot arm 303. The robot assembly 301 can bring the one or more end effectors 305 into engagement with the glass ribbon 103. In some embodiments, the robot assembly 301 can move the one or more end effectors 305 in the travel direction 154 along a path that is substantially parallel to the travel path 221. The robot assembly 301 can apply a bending force to the glass ribbon 103 in a direction perpendicular to the first major surface 215 and/or the second major surface 216 to produce a bending moment about the x-axis. For example, the bending moment about the x-axis induced by the robot assembly 301 can produce a tensile stress across a score line created by the glass separator 149 (e.g., illustrated in FIG. 1) across the separation path 151 that extends along the x-axis. The tensile stress can cause a crack to propagate through the thickness of the glass ribbon 103, thereby separating a portion of the glass ribbon 103 from an upstream portion of the glass ribbon.

[0051] In some embodiments, the one or more end effectors 305 can engage the first major surface 215 and/or the second major surface 216 of the glass ribbon 103. For example, the one or more end effectors 305 can comprise a plurality of end effectors (e.g., four end effectors). In some embodiments, the one or more end effectors 305 can comprise soft vacuum suction cups. Vacuum lines can be connected to the suction cups and can be attached to a vacuum source that can generate a negative pressure or vacuum at the suction cups. The suction cups can engage the glass ribbon 103 and, in some embodiments, form a vacuum suction attachment with the glass ribbon 103 such that relative movement between the glass ribbon 103 and the one or more end effectors 305 is limited. In some embodiments, the four end effectors can engage the first major surface 215 of the glass ribbon 103 at four locations, for example, a first engagement position 307, a second engagement position 309, a third engagement position 311, and a fourth engagement position 313. The first engagement position 307 and the second engagement position 309 can be located adjacent to the first outer edge 153 of the glass ribbon 103. The first engagement position 307 and the second engagement position 309 can be oriented along the travel direction 154. The third engagement position 311 and the fourth engagement position 313 can be located adjacent to the second outer edge 155 of the glass ribbon 103. The third engagement position 311 and the fourth engagement position 313 can be oriented along the travel direction 154. In some embodiments, the glass ribbon 103 can exert a force upon the one or more end effectors 305 when the one or more end effectors 305 engage the glass ribbon 103. For example, the forces exerted upon the one or more end effectors 305 can comprise a force in a direction of one or more of the x-axis, the y-axis, or the z-axis. In addition, or in the alternative, the glass ribbon 103 can exert a torque upon the one or more end effectors 305, for example, about the x-axis (e.g., M _x ), about the y- axis (e.g., M _y ), and/or about the z-axis (e.g., M _z ).

[0052] Referring to FIG. 4, a side view of the glass manufacturing apparatus 100 is illustrated along line 4-4 of FIG. 3 in which the glass ribbon 103 is moving along the travel path 221 in the travel direction 154. In some embodiments, the one or more end effectors 305 of the robot assembly 301 can comprise a first end effector 401 and a second end effector 403. The first end effector 401 can engage the glass ribbon 103 at the first engagement position 307 (e.g., illustrated in FIG. 3) while the second end effector 403 can engage the glass ribbon 103 at the second engagement position 309 (e.g., illustrated in FIG. 3). In some embodiments, the one or more end effectors 305 can comprise a third end effector and a fourth end effector, with the third end effector obscured from view by the first end effector 401 and the fourth end effector obscured from view by the second end effector 403. The first end effector 401, the second end effector 403, and other end effectors may be substantially identical in structure and function, for example, by comprising suction cups.

[0053] In some embodiments, the robot assembly 301 can comprise a sensor 405 that can sense and/or signal information indicative of one or more forces (e.g., linear force, torque, etc.) at the one or more end effectors 305, and, thus, being exerted on the glass ribbon 103 by the one or more end effectors 305 when the one or more end effectors 305 engage the glass ribbon 103. In some embodiments, the sensor 405 can comprise a multiple axis or multiple degree-of-freedom force sensor, for example, a six-axis force and/or torque sensor (or six-degrees-of-freedom force sensor) that can sense forces in six directions. In some embodiments, the sensor 405 can be configured to sense forces in more or less than six directions. In some embodiments, forces that can be sensed by the sensor 405 can comprise a force in a direction of the x-axis F _x , a force in a direction of the y-axis F _y , a force in a direction of the z-axis F _z , a torque (or moment of force) about the x-axis M _x , a torque (or moment of force) about the y-axis M _y , and/or a torque (or moment of force) about the z-axis M _z . As used herein, the term “force” can comprise a linear force (e.g., along the x-axis, y-axis, z-axis, etc.) and/or a force component of the torque. In some embodiments, the sensing components of the sensor 405 can comprise a transducer that can sense forces in the six directions. The sensor 405 can further comprise programming and/or circuitry that can generate and transmit electrical signals conveying sensed information. In some embodiments, the sensor 405 can comprise a sampling rate of 50 hertz (Hz) or more, or, for example, a sampling rate of 100 Hz or more. Some non-limiting examples of the sensor 405 can comprise, for example, six-degrees-of-freedom force sensors available from FANUC America Corp., under the trade designations FS-lOiA™, FS-30™, and FS-60™; force/torque sensors available from ATI Industrial Automation, Inc., for example under the trade designation Omega 160™; etc.

[0054] In some embodiments, the glass manufacturing apparatus 100 can comprise a control assembly 409 that can receive data from the sensor 405 and operate the robot arm 303. The control assembly 409 can comprise a control device (e.g., a computer, a computer-like device, a programmable logic controller, etc.) configured to (e.g., programmed to, encoded to, designed to, and/or made to) operate the robot arm 303. For example, the control assembly 409 may be electrically connected to (e.g., wired or wireless) the sensor 405 and the robot arm 303. In some embodiments, the control assembly 409 can receive force data 411 from the sensor 405. The control assembly 409 can transmit motion instructions 413 to the robot arm 303. In some embodiments, the control assembly 409 can comprise one or more controllers, for example, a first controller 415 and a second controller 417. In some embodiments, the first controller 415 can control operation of the robot arm 303 while the second controller 417 can process and/or analyze the force data 411 (e.g., force-related feedback information) from the sensor 405 and can generate responsive adjustments to the robot arm 303. For example, the motion instructions 413 can be transmitted from the first controller 415 to the robot arm 303 and/or to a separate controller at the robot arm 303 that controls movement of the segments of the robot arm 303. The robot arm 303 can move in response to the motion instructions 413. For example, the motion instructions 413 may specify one or more of a path along which the robot arm 303 may travel, a velocity of the robot arm 303, a distance to be traveled by the robot arm 303, etc. The robot arm 303 can therefore move in accordance with the motion instructions 413.

[0055] The first controller 415 can receive the force data 411 from the sensor 405, whereupon the first controller 415 can transmit the force data 411 to the second controller 417. In some embodiments, the force data 411 from the sensor 405 can be transmitted directly to the second controller 417 by bypassing the first controller 415. The glass ribbon 103 can exert a force upon the one or more end effectors 305, with the force configured to be sensed by the sensor 405 and transmitted as part of the force data 411 to the control assembly 409. For example, the force data 411 may comprise the forces that may be sensed along one or more of the x-axis, the y-axis, the z-axis, a torque about the x-axis, a torque about the y-axis, or a torque about the z-axis. The second controller 417 can determine possible adjustments to the operation of the robot arm 303 such as, for example, changes or adjustments in one or more of a position, a path, or a velocity of the one or more end effectors 305. The adjustments determined by the second controller 417 may be based, in part, on the force data 411 received by the second controller 417. In some embodiments, the second controller 417 can transmit these adjustments as adjustment data 419 to the first controller 415. The first controller 415 can receive the adjustment data 419 from the second controller 417 and can incorporate the adjustment data 419 into the motion instructions 413 to the robot arm 303. In some embodiments, a user can input user-inputted data 421 to the first controller 415. For example, in some embodiments, the user-inputted data 421 can represent the motion instructions 413 for the robot arm 303 during a first operational cycle of the robot arm 303, wherein the user-inputted data 421 can comprise one or more of an initial position, an initial path, or an initial velocity of the one or more end effectors 305. In some embodiments, the motion instructions 413 can subsequently be changed based on the force data 411, such that the user-inputted data 421 may no longer be implemented.

[0056] In some embodiments, methods for forming the glass ribbon 103 can comprise engaging the glass ribbon 103 with an end effector (e.g., the one or more end effectors 305) attached to the robot arm 303. For example, the robot arm 303 can move the one or more end effectors 305 between a disengaged position 427 and an engaged position 429. In the disengaged position 427, the one or more end effectors 305 may not contact or engage the glass ribbon 103 and may be spaced a distance apart from a major surface (e.g., the first major surface 215) of the glass ribbon 103. To engage the glass ribbon 103, the robot arm 303 can move the one or more end effectors 305 in an engagement direction 425 toward the glass ribbon 103. The one or more end effectors 305 can be moved in the engagement direction 425 at least until the one or more end effectors 305 engage the first major surface 215, thus forming a suction attachment with the first major surface 215. When the one or more end effectors 305 engage the glass ribbon 103, relative movement between the glass ribbon 103 and the one or more end effectors 305 may be substantially limited, such that glass ribbon 103 and the one or more end effectors 305 may move together with one another.

[0057] FIG. 5 illustrates the one or more end effectors 305 in engagement (e.g., in the engaged position 429) with the first major surface 215 of the glass ribbon 103. For example, the one or more end effectors 305 can engage a first ribbon portion 501 of the glass ribbon 103. The first ribbon portion 501 can be located downstream from a second ribbon portion 503 of the glass ribbon 103 relative to the travel direction 154. For example, as the glass ribbon 103 travels along the travel direction 154, the first ribbon portion 501 can pass a location prior to the second ribbon portion 503 passing the same location. In some embodiments, a first operational cycle may last from the engagement of the first ribbon portion 501 with the one or more end effectors 305 (e.g., illustrated in FIG. 4) to a separation of the first ribbon portion 501 from the second ribbon portion 503 (e.g., illustrated in FIG. 7).

[0058] In some embodiments, methods for forming the glass ribbon 103 can comprise moving the one or more end effectors 305 at a robot velocity, for example, a first robot velocity 505, in the travel direction 154. For example, the glass ribbon 103 can move along the travel path 221 in the travel direction 154 at a ribbon velocity 507. In some embodiments, methods for forming the glass ribbon 103 can comprise sensing a force, for example, a first force, exerted by the first ribbon portion 501 of the glass ribbon 103 upon the one or more end effectors 305 during the first operational cycle. For example, in some embodiments, a ribbon velocity and a ribbon path of the first ribbon portion 501 may or may not match a pre-programmed robot velocity and a robot path of the one or more end effectors 305.

[0059] In some embodiments, the first robot velocity 505 and the ribbon velocity 507 can be substantially identical, for example, by comprising the same magnitude and the same direction (e.g., along the travel direction 154). When the first robot velocity 505 and the ribbon velocity 507 are substantially identical and when the paths along which the first ribbon portion 501 and the one or more end effectors 305 travel are substantially parallel, then the first ribbon portion 501 and the one or more end effectors 305 may be traveling at the same speed along parallel paths. As such, the first force that may be sensed may be zero or close to zero. For example, due to the first robot velocity 505 and the ribbon velocity 507 being substantially identical, relative motion between the first ribbon portion 501 and the one or more end effectors 305 along the y-axis may be negligible, such that the first force may be zero or close to zero. In some embodiments, the first force may be sensed at a plurality of locations (e.g., along a plurality of axes, for example, the x-axis, the y-axis, the z-axis, a torque about the x-axis, a torque about the y-axis, and/or a torque about the z-axis).

[0060] As used herein, the term “velocity” (e.g., as used with the first robot velocity 505, the ribbon velocity 507, other velocities herein, etc.) is not limited to a single velocity (e.g., a single magnitude of speed in a single direction). Rather, in some embodiments, as used herein, “velocity” can comprise a set of varying velocities. For example, during an operational cycle, in some embodiments, the velocity, for example, one or more of the first robot velocity 505, the ribbon velocity 507, etc. can comprise a constant velocity (e.g., a constant speed in a single direction). In some embodiments, however, “velocity” is not limited to a constant velocity, but, rather, a set of varying velocities during an operational cycle. For example, in some embodiments, the velocity (e.g., the first robot velocity 505, the ribbon velocity 507, etc.) can change during the operational cycle, for example, between about every 10 ms to about every 50 ms. The changing velocity can comprise, for example, a changing magnitude of speed and/or a changing direction. As such, the “velocity” during an operational cycle can comprise a plurality of velocities that may change in speed and/or direction.

[0061] In some embodiments, methods for forming the glass ribbon 103 can comprise changing the speed of the one or more end effectors 305 from the first robot velocity 505 to a second robot velocity 509 when a magnitude of the force exceeds a predetermined value. The magnitude of the force can comprise an absolute value of the force. For example, the sensor 405 can sense the force that is exerted upon the one or more end effectors 305 by the first ribbon portion 501. The sensor 405 can transmit this force as the force data 411 to the first controller 415, which can then be transferred to the second controller 417. In some embodiments, the second controller 417 can compare a magnitude of the force data 411 to a predetermined value that may be set by a user. In some embodiments, the force data 411 may comprise a magnitude of the force that may be within the predetermined value, for example, when the first robot velocity 505 and the ribbon velocity 507 are substantially identical and relative motion between the first ribbon portion 501 and the one or more end effectors 305 is zero. The force data 411 may therefore be indicative of a force that is zero or close to zero, which may be within the predetermined value. In some embodiments, when a magnitude of the force that is sensed by the sensor 405 is within the predetermined value, a speed of the one or more end effectors 305 may not be changed, but, rather, the speed of the one or more end effectors 305 may remain constant. As such, the first controller 415 may not alter the motion instructions 413 that are transmitted to the robot arm 303.

[0062] In some embodiments, a magnitude of the force data 411 may exceed the predetermined value, for example, when the first robot velocity 505 and the ribbon velocity 507 are not identical and relative motion exists between the first ribbon portion 501 and the one or more end effectors 305. The force data 411 may therefore be indicative of a force that is not near zero, but rather, may be greater than zero or less than zero and, thus, may exceed the predetermined value. In some embodiments, when a magnitude of the force that is sensed by the sensor 405 exceeds the predetermined value, a speed of the one or more end effectors 305 may be changed. For example, the first controller 415 may change the motion instructions 413 that are transmitted to the robot arm 303 to provide motion instructions 413 that change the speed of the robot arm 303 from the first robot velocity 505 to the second robot velocity 509. It will be appreciated that in FIG. 5, the length of the lines representing the first robot velocity 505 and the second robot velocity 509 may be different, thus representing a change in speed of the one or more end effectors 305 from the first robot velocity 505 to the second robot velocity 509. In some embodiments, the second robot velocity 509 may be closer to the ribbon velocity 507 than the first robot velocity 505, for example, with a first difference between the second robot velocity 509 and the ribbon velocity 507 being less than a second difference between the first robot velocity 505 and the ribbon velocity 507. In some embodiments, when the second robot velocity 509 is substantially identical to the ribbon velocity 507, such that the force sensed by the sensor 405 may be zero or close to zero, then the force sensed by the sensor 405 may not exceed the predetermined value. However, in some embodiments, when the second robot velocity 509 differs from the ribbon velocity 507, such that the force sensed by the sensor 405 may be zero or close to zero, then a magnitude of the force sensed by the sensor 405 may not exceed the predetermined value. In this way, changing the speed can occur when a magnitude of the first force exceeds the predetermined value, however, if the magnitude of the first force is within the predetermined value, then the speed may not be changed.

[0063] In some embodiments, the first ribbon portion 501 can exert a force upon the one or more end effectors 305 along a first force direction 511 that may be in the same direction as the travel direction 154. When the first ribbon portion 501 exerts a force along the first force direction 511, then the ribbon velocity 507 may be greater than the first robot velocity 505, such that the first ribbon portion 501 may be traveling faster than the one or more end effectors 305. To compensate for this discrepancy between the ribbon velocity 507 and the first robot velocity 505, the second robot velocity 509 may be greater than (e.g., faster than) the second robot velocity 509, such that the second robot velocity 509 may more closely match the ribbon velocity 507. In some embodiments, the first ribbon portion 501 can exert a force upon the one or more end effectors 305 along a second force direction 513 that may be opposite the first force direction 511 and opposite the travel direction 154. When the first ribbon portion 501 exerts a force along the second force direction 513, then the ribbon velocity 507 may be less than the first robot velocity 505, such that the first ribbon portion 501 may be traveling slower than the one or more end effectors 305. To compensate for this discrepancy between the ribbon velocity 507 and the first robot velocity 505, the second robot velocity 509 may be less than (e.g., slower than) the second robot velocity 509, such that the second robot velocity 509 may more closely match the ribbon velocity 507.

[0064] In some embodiments, methods for forming the glass ribbon 103 can comprise quantifying the ribbon velocity 507 by correlating the ribbon velocity 507 to the robot velocity (e.g., the first robot velocity 505 or the second robot velocity 509) when a magnitude of the force is within a predetermined value. For example, in some embodiments, when the robot velocity (e.g., the first robot velocity 505 or the second robot velocity 509) of the one or more end effectors 305 substantially matches the ribbon velocity 507 of the first ribbon portion 501, relative motion between the first ribbon portion 501 and the one or more end effectors 305 may be negligible, such that the first force may be zero or close to zero. In some embodiments, when the first force is zero or close to zero, then a magnitude of the first force may be within the predetermined value. As such, with the magnitude of the first force within the predetermined value, the robot velocity (e.g., the first robot velocity 505 or the second robot velocity 509) can be assumed to substantially match the ribbon velocity 507. The robot velocity, for example, a magnitude of the robot velocity, may be a known quantity due to the first controller 415 transmitting the motion instructions 413 to the robot arm 303. The ribbon velocity 507 can therefore be quantified by correlating the ribbon velocity 507 to the robot velocity (e.g., the first robot velocity 505 or the second robot velocity 509), for example, by assigning the known robot velocity to the ribbon velocity 507.

[0065] In some embodiments, when a magnitude of the first force exceeds the predetermined value, then relative motion between the first ribbon portion 501 and the one or more end effectors 305 may exist, such that the first force may be non-negligible. In some embodiments, the relative motion may cause a magnitude of the first force to exceed the predetermined value. When the magnitude of the first force exceeds the predetermined value, then the robot velocity can be assumed to be different than the ribbon velocity 507. As such, the ribbon velocity 507 may not be quantifiable until the robot velocity is changed to substantially match the ribbon velocity 507 such that the magnitude of the first force is within the predetermined value.

[0066] In some embodiments, quantifying the ribbon velocity 507 can comprise determining one or more of an average ribbon velocity or an instantaneous ribbon velocity. For example, in some embodiments, the quantifying the ribbon velocity 507 can comprise determining an average ribbon velocity during a time period from the engaging (e.g., illustrated in FIG. 4) the first ribbon portion 501 with the one or more end effectors 305 to a separation (e.g., illustrated in FIG. 7) of the first ribbon portion 501 from the second ribbon portion 503 of the glass ribbon 103. For example, the average ribbon velocity can be represented by equation

[0067] (1) ^V avg [0068] In equation (1), P(t _s tan) can represent a position of the first ribbon portion 501 when the one or more end effectors 305 first engages the first ribbon portion 501. P(tend) can represent a position of the first ribbon portion 501 when the first ribbon portion 501 is separated (e.g., illustrated in FIG. 7) from the second ribbon portion 503. Thus, the numerator of equation (1) (e.g., P(t _e nd) - P(tstan)) can represent a distance that the first ribbon portion 501 travels from the time that the one or more end effectors 305 first engages the first ribbon portion 501 to the time that the first ribbon portion 501 is separated from the second ribbon portion 503. In some embodiments, tstan can represent a time that the one or more end effectors 305 first engages the first ribbon portion 501 while tend can represent a time that the first ribbon portion 501 is separated from the second ribbon portion 503. Thus, the denominator of equation (1) (e.g., tend - tstan) can represent the time that has elapsed between when the one or more end effectors 305 first engages the first ribbon portion 501 to when the first ribbon portion 501 is separated from the second ribbon portion 503. As such, the average ribbon velocity of the first ribbon portion 501 can be determined during a first operational cycle, for example, from when the one or more end effectors 305 first engages the first ribbon portion 501 to the separation of the first ribbon portion 501 from the second ribbon portion 503.

[0069] In addition, or in the alternative, in some embodiments, the quantifying the ribbon velocity can comprise determining an instantaneous ribbon velocity during a sampling period that may be less than about 2 milliseconds (ms), less than about 1 millisecond, etc. For example, the instantaneous ribbon velocity can comprise a real-time ribbon velocity of the glass ribbon 103 within a sampling period. In some embodiments, the instantaneous ribbon velocity can be represented by equation (2):

[0071] In equation (2), At can represent a sampling period that may be less than about 2 milliseconds. P(t _k ) can represent a position of the first ribbon portion 501 at time t _k while P(t _k + At) can represent a position of the first ribbon portion 501 at time t _k + At, or, in other words, after the sampling period has passed. For example, the numerator of equation (2) (e.g., P(t _k + At) — P{t _k )) can represent a distance that the first ribbon portion 501 travels during the sampling period At, which may be less than about 2 milliseconds, less than about 1 millisecond, etc. In some embodiments, the sampling period can be within a range from about 1 millisecond to about 2 milliseconds. The denominator of equation (2) At can represent the time that has elapsed, for example, the sampling period. As such, the instantaneous ribbon velocity of the first ribbon portion 501 can be determined during the sampling period.

[0072] In some embodiments, methods of forming the glass ribbon 103 can comprise adjusting a parameter of the glass ribbon 103 based on the ribbon velocity 507. For example, in some embodiments, once the ribbon velocity 507 is known (e.g., the average ribbon velocity and/or the instantaneous ribbon velocity), a parameter of the glass ribbon 103 can be adjusted to compensate for the ribbon velocity 507. For example, if the ribbon velocity 507 is less than a target ribbon velocity, then adjusting the parameter can comprise maintaining a constant length of the first ribbon portion 501 and the second ribbon portion 503 of the glass ribbon 103. Due to the ribbon velocity 507 being less than the target ribbon velocity, the separating of the first ribbon portion 501 from the second ribbon portion 503 can be delayed to compensate for the slower ribbon velocity 507, thus allowing for a length of the first ribbon portion 501 to be longer prior to separating. If the ribbon velocity 507 is faster than the target ribbon velocity, then the separation of the first ribbon portion 501 from the second ribbon portion 503 can occur earlier, thus allowing for a length of the first ribbon portion 501 to be shorter prior to separating. In some embodiments, additional parameters that can be adjusted may comprise, for example, localized heating of the glass ribbon 103, altering a chemistry of the glass ribbon 103, etc. In some embodiments, the second ribbon portion 503 can be separated from an upstream portion of the glass ribbon 103 such that a length of the second ribbon portion 503 matches a length of the first ribbon portion 501. Therefore, in some embodiments, a constant length of the first ribbon portion 501 and the second ribbon portion 503 can be maintained. In some embodiments, a length of the first ribbon portion 501 and/or the second ribbon portion 503 can be adjusted across a width of the first ribbon portion 501 and/or the second ribbon portion 503. For example, in some embodiments, the length of the first ribbon portion 501 and/or the second ribbon portion 503 (e.g., and other ribbon portions of the glass ribbon 103) can be adjusted along the first outer edge 153, a second outer edge 155, and/or at locations between the first outer edge 153 and the second outer edge 155. In some embodiments, the changing and/or maintaining of the length of the ribbon portions (e.g., first ribbon portion 501, the second ribbon portion 503, etc.) can be made based on a change in a process parameter, for example, a change in a diameter of the pulling roll assembly 158, a speed of the glass separator 149, etc.

[0073] Referring to FIG. 6, in some embodiments, as part of a separation process, a score line 601 can be formed in the glass ribbon 103. For example, to separate the first ribbon portion 501 from the second ribbon portion 503, the glass separator 149 can form the score line 601 in the second major surface 216, though, in addition, or in the alternative, the score line 601 can be formed at the first major surface 215. In some embodiments, the score line 601 can define a boundary between the first ribbon portion 501 and the second ribbon portion 503. For example, the first ribbon portion 501 can lie on one side of the score line 601 while the second ribbon portion 503 can lie on an opposing side of the score line 601.

[0074] Referring to FIGS. 6-7, in some embodiments, methods for forming the glass ribbon 103 can comprise separating the first ribbon portion 501 of the glass ribbon 103 from the second ribbon portion 503 of the glass ribbon 103 prior to changing the speed. For example, as illustrated in FIG. 7, the first operational cycle can comprise manipulating the robot arm 303 to move the one or more end effectors 305 and cause the first ribbon portion 501 to bend relative to a remainder of the glass ribbon 103, for example, the second ribbon portion 503. In some embodiments, the one or more end effectors 305 can pivot the first ribbon portion 501 about the x-axis, for example, counterclockwise about the x-axis, at the score line 601. The pivoting of the first ribbon portion 501 relative to the second ribbon portion 503 at the score line 601 can cause the first ribbon portion 501 to separate from the second ribbon portion 503. In some embodiments, the first ribbon portion 501 can be moved in a separation direction 701 away from the second ribbon portion 503 and away from the travel path 221 along which the second ribbon portion 503 travels. In some embodiments, the robot arm 303 can move the first ribbon portion 501 to a discrete area and release the first ribbon portion 501 from the one or more end effectors 305, thus disengaging the one or more end effectors 305 from the first ribbon portion 501.

[0075] In some embodiments, the robot arm 303 can move at the first robot velocity 505 for the duration of the first operational cycle, for example, beginning with the engagement of the first ribbon portion 501 with the one or more end effectors 305 and concluding with the separation of the first ribbon portion 501 from the second ribbon portion 503. By moving at the first robot velocity 505 the duration of the first operational cycle, methods for forming the glass ribbon 103 can comprise maintaining the speed of the one or more end effectors 305 at the first robot velocity 505, for example, throughout the first operational cycle, during a time period from the engaging the first ribbon portion 501 with the one or more end effectors 305 to the separating of the first ribbon portion 501 from the second ribbon portion 503. By maintaining the speed of the one or more end effectors 305 and by separating the first ribbon portion 501 prior to changing the speed, the one or more end effectors 305 may remain at the first robot velocity 505 during the first operational cycle without changing to the second robot velocity 509 (e.g., illustrated in FIG. 5)

[0076] In some embodiments, the speed of the one or more end effectors 305 may be maintained at the first robot velocity 505 due to a magnitude of the force sensed by the sensor 405 being within the predetermined value. For example, when the first robot velocity 505 is substantially identical to the ribbon velocity 507, then the force sensed by the sensor 405 may be zero or close to zero, and, thus, a magnitude of the force may be within the predetermined value. However, in some embodiments, the speed of the one or more end effectors 305 may be maintained at the first robot velocity 505 during the first operational cycle regardless of the force sensed by the sensor 405. For example, it may be beneficial to maintain the one or more end effectors 305 at the first robot velocity 505 during the first operational cycle even if a magnitude of the force sensed by the sensor 405 exceeds the predetermined value. This may be due, in part, to reduce the demand for data acquisition and computing power. For example, by not changing the first robot velocity 505 to the second robot velocity 509 during the first operational cycle, data transfer (e.g., in the form of updated motion instructions 413) from the first controller 415 to the robot arm 303 may be reduced. In addition, computing power may likewise be reduced due to a reduced demand for generating the motion instructions 413. Accordingly, in some embodiments, the control assembly 409 can change the robot velocity in real-time during the first operational cycle (e.g., as described relative to FIG. 5) from the first robot velocity 505 to the second robot velocity 509 in response to a magnitude of the force sensed by the sensor 405 exceeding the predetermined value. However, in other embodiments, the control assembly 409 can maintain the robot velocity at the first robot velocity 505 during the first operational cycle even if the magnitude of the force sensed by the sensor 405 exceeds the predetermined value. In some embodiments, regardless of whether the control assembly 409 changes the robot velocity during the first operational cycle, the control assembly 409 can receive the force data 411 throughout the first operational cycle and store the force data 411, for example, in the memory. The force data 411 that may be stored can comprise, for example, one or more of the force sensed by the sensor 405, the velocity (e.g., the first robot velocity 505, the second robot velocity 509, etc.) of the one or more end effectors 305, an estimate of the ribbon velocity 507 based on the force sensed by the sensor 405 at a robot velocity, an instantaneous ribbon velocity, an average ribbon velocity, etc.

[0077] Referring to FIG. 8, in some embodiments, methods for forming the glass ribbon 103 can comprise separating the first ribbon portion 501 (e.g., illustrated in FIG. 7) prior to engaging the second ribbon portion 503. For example, once the first ribbon portion 501 is separated from the second ribbon portion 503, the one or more end effectors 305 can disengage from the first ribbon portion 501. In some embodiments, methods for forming the glass ribbon 103 can comprise engaging the second ribbon portion 503 of the glass ribbon 103 prior to changing the speed of the one or more end effectors 305. For example, in some embodiments, the control assembly 409 can maintain the robot velocity at the first robot velocity 505 during the first operational cycle even if the magnitude of the force sensed by the sensor 405 exceeds the predetermined value. After the completion of the first operational cycle in which the first ribbon portion 501 may be separated from the second ribbon portion 503, the one or more end effectors 305 can engage the second ribbon portion 503. For example, the one or more end effectors 305 can engage the second ribbon portion 503 in a substantially identical manner to the one or more end effectors 305 engaging the first ribbon portion 501 (e.g., illustrated in FIG. 4 wherein the robot arm 303 moves the one or more end effectors 305 in the engagement direction 425). In some embodiments, methods for forming the glass ribbon 103 can comprise engaging the second ribbon portion 503 with the one or more end effectors 305 following the first operational cycle. The engagement of the second ribbon portion 503 with the one or more end effectors 305 can represent the start of the second operational cycle, which may last until the second ribbon portion 503 is separated from a third ribbon portion 801.

[0078] In some embodiments, the speed of the one or more end effectors 305 can be changed to the second robot velocity 509 (e.g., from the first robot velocity 505) prior to the start of the second operational cycle. For example, during the first operational cycle, the first controller 415 can receive the force data 411 from the sensor 405, wherein the force data 411 is indicative of a first force exerted upon the one or more end effectors 305 by the first ribbon portion 501 (e.g., illustrated in FIGS. 4-7). If a magnitude of the first force is within the predetermined value for the duration of the first operational cycle, then the first robot velocity 505 (e.g., illustrated in FIGS. 5-7) may be substantially identical to the ribbon velocity 507. However, if the magnitude of the first force exceeds the predetermined value during the first operational cycle, then the first robot velocity 505 (e.g., illustrated in FIGS. 5-7) differs from the ribbon velocity 507. In some embodiments, the first force may be indicative of this difference in velocity, such that the second controller 417 can process and/or analyze the first force to determine a correction to the first robot velocity 505. For example, the second controller 417 can generate the second robot velocity 509, which may comprise a correction to the first robot velocity 505 based on the first force, and transmit the second robot velocity 509 to the first controller 415 as the adjustment data 419. In response, the first controller 415 can transmit the motion instructions 413, which may contain the second robot velocity 509, to the robot arm 303. In some embodiments, the robot arm 303 can then move the one or more end effectors 305 at the second robot velocity 509 for the duration of the second operational cycle. In this way, in some embodiments, methods for forming the glass ribbon 103 can comprise changing the speed of the one or more end effectors 305 from the first robot velocity 505 (e.g., illustrated in FIGS. 5-7) to the second robot velocity 509 based on the first force and moving the one or more end effectors 305 at the second robot velocity 509 in the travel direction 154 during the second operational cycle. In some embodiments, a difference between the second robot velocity 509 and the ribbon velocity 507 may be less than a difference between the first robot velocity 505 and the ribbon velocity 507.

[0079] In some embodiments, methods for forming the glass ribbon 103 can comprise sensing a second force exerted by the second ribbon portion 503 upon the one or more end effectors 305 during the second operational cycle. For example, the sensing of the second force can be substantially identical to the sensing of the first force (e.g., illustrated and described relative to FIG. 5). In some embodiments, the second robot velocity 509 and the ribbon velocity 507 can be substantially identical, for example, by comprising the same magnitude and the same direction (e.g., along the travel direction 154). When the second robot velocity 509 and the ribbon velocity 507 are substantially identical, then the second ribbon portion 503 and the one or more end effectors 305 may be traveling along the same path at the same speed. As such, the second force that may be sensed may be zero or close to zero. In some embodiments, when the magnitude of the second force exceeds the predetermined value, the second robot velocity 509 of the one or more end effectors 305 can be changed (e.g., to a third velocity) in a similar manner to the change from the first robot velocity 505 to the second robot velocity 509.

[0080] Referring to FIG. 9, in some embodiments, methods for forming the glass ribbon 103 can comprise separating the second ribbon portion 503 from the third ribbon portion 801 prior to engaging the third ribbon portion 801. For example, the second ribbon portion 503 can be removed in a substantially identical manner as to how the first ribbon portion 501 (e.g., illustrated in FIG. 7) is removed from the second ribbon portion 503. For example, the glass separator 149 can form a score line 901 in the glass ribbon 103, for example, in the second major surface 216 and/or in the first major surface 215. In some embodiments, the score line 901 can define a boundary between the second ribbon portion 503 and the third ribbon portion 801. For example, the second ribbon portion 503 can lie on one side of the score line 901 while the third ribbon portion 801 can lie on an opposing side of the score line 901. In some embodiments, during the second operational cycle, the robot arm 303 can be manipulated to move the one or more end effectors 305 and cause the second ribbon portion 503 to bend relative to a remainder of the glass ribbon 103, for example, the third ribbon portion 801. In some embodiments, the one or more end effectors 305 can pivot the second ribbon portion 503 about the x-axis, for example, counterclockwise about the x-axis, at the score line 901. The pivoting of the second ribbon portion 503 relative to the third ribbon portion 801 at the score line 901 can cause the second ribbon portion 503 to separate from the third ribbon portion 801. [0081] In some embodiments, methods for forming the glass ribbon 103 can comprise maintaining the speed of the one or more end effectors 305 at the second robot velocity 509 throughout the second operational cycle during a time period from the engaging the second ribbon portion 503 with the one or more end effectors 305 to the separating of the second ribbon portion 503 from the third ribbon portion 801. For example, the maintaining the speed of the one or more end effectors 305 at the second robot velocity 509 throughout the second operational cycle can be substantially identical to the maintaining the speed of the one or more end effectors 305 at the first robot velocity 505 (e.g., illustrated in FIGS. 5-7) during the first operational cycle. In some embodiments, the speed of the one or more end effectors 305 may be maintained at the second robot velocity 509 due to a magnitude of the second force sensed by the sensor 405 being within the predetermined value. When the second force is within the predetermined value, then a magnitude of the second robot velocity 509 may be substantially identical to the ribbon velocity 507. However, in some embodiments, the speed of the one or more end effectors 305 may be maintained at the second robot velocity 509 during the second operational cycle regardless of the force sensed by the sensor 405. For example, to reduce the demand for data acquisition and computing power, the control assembly 409 may not change the robot velocity in real-time during the second operational cycle from the second robot velocity 509 to a third robot velocity even if the magnitude of the second force sensed by the sensor 405 exceeds the predetermined value. In some embodiments, even if the second robot velocity 509 is maintained throughout the second operational cycle, the control assembly 409 can receive the force data 411 throughout the second operational cycle and store the force data 411, for example, in the memory.

[0082] Referring to FIG. 10, in some embodiments, methods for forming the glass ribbon 103 can comprise engaging the third ribbon portion of the glass ribbon 103 with the one or more end effectors 305 following the second operational cycle. For example, in some embodiments, after the completion of the second operational cycle in which the second ribbon portion 503 may be separated from the third ribbon portion 801, the one or more end effectors 305 can disengage from the second ribbon portion 503 and engage the third ribbon portion 801. The one or more end effectors 305 can engage the third ribbon portion 801 in a substantially identical manner to the one or more end effectors 305 engaging the first ribbon portion 501 and/or the second ribbon portion 503. The engagement of the third ribbon portion 801 with the one or more end effectors 305 can represent the start of the third operational cycle, which may last until the third ribbon portion 801 is separated from another portion of the glass ribbon 103 (e.g., a fourth ribbon portion).

[0083] In some embodiments, methods for forming the glass ribbon 103 can comprise changing the speed of the one or more end effectors 305 from the second robot velocity 509 (e.g., illustrated in FIGS. 5-9) to a third robot velocity 1001 based on one or more of the first force (e.g., exerted upon the one or more end effectors 305 during the first operational cycle illustrated in FIGS. 4-7) or the second force (e.g., exerted upon the one or more end effectors 305 during the second operational cycle illustrated in FIGS. 7-9) and moving the one or more end effectors 305 at the third robot velocity 1001 in the travel direction 154 during the third operational cycle. For example, in some embodiments, the speed of the one or more end effectors 305 from the second robot velocity 509 to the third robot velocity 1001 can be changed based on the force data 411 from the most recent operational cycle, for example, the second operational cycle. In some embodiments, if the magnitude of the second force sensed during the second operational cycle exceeds the predetermined value, then the second robot velocity 509 differs from the ribbon velocity 507. The second force may be indicative of this difference in velocity, such that the second controller 417 can process and/or analyze the second force to determine a correction to the second robot velocity 509. For example, the second controller 417 can generate the third robot velocity 1001, which may comprise a correction to the second robot velocity 509. The third robot velocity 1001 may be transmitted to the first controller 415 as the adjustment data 419 and, in response, the first controller 415 can transmit the motion instructions 413 to the robot arm 303. The robot arm 303 can then move the one or more end effectors 305 at the third robot velocity 1001 for the duration of the third operational cycle.

[0084] In some embodiments, changing the speed of the one or more end effectors 305 from the second robot velocity 509 to the third robot velocity 1001 is not limited to being based on the force data 411 from the most recent operational cycle. Rather, in some embodiments, the speed can be changed based on a combination of the first force sensed during the first operational cycle and the second force sensed during the second operational cycle. For example, in some embodiments, the second controller 417 can combine the first force and the second force, such as by averaging the first force and the second force, to determine a correction to the second robot velocity 509. The second controller 417 can then generate the third robot velocity 1001, which may be transmitted to the robot arm 303 by the first controller 415 via the motion instructions 413.

[0085] FIG. 11 illustrates an exemplary control diagram 1101 or control architecture representing controls that may be implemented by the control assembly 409. In some embodiments, a user may initially enter the user-inputted data 421 to a control algorithm 1103. The control algorithm 1103 can compare the force data from the sensor 405 to the user-inputted data 421. Based on a difference between the magnitude of the force sensed by the sensor 405 and the user-inputted data 421, the control algorithm 1103 can generate motion instructions 1104 to a robot controller 1105, which can control movement of the robot arm 303. The sensor 405 can sense the force exerted by the glass ribbon 103 upon the one or more end effectors 305, and transmit the force data 411 to a filter 1107, whereupon signal filtering of the force data 411 can be performed. In some embodiments, the force data 411 can then be transmitted to a memory 1109 for storage. For example, the memory 1109 can store the force data for some or all of an operational cycle, such as the first operational cycle, the second operational cycle, etc. In some embodiments, the stored force data from an operational cycle can be transmitted to the control algorithm 1103, whereupon the control algorithm 1103 can compare the force data to a predetermined value, and can update the motion instructions 1104 accordingly.

[0086] In some embodiments, the control algorithm 1103 can be represented by equation (3):

[0087] (3) U _f c(t) = u _fc-! (t) + OAy _fc _i(t)

[0088] In equation (3), t can represent a sampled time series within one operational cycle while can represent a difference between a desired force profile (e.g., during the operational cycle) and an actual force profile y _fc-1 that is sensed by the sensor 405. F can represent an update law that can be causal or non-causal. For example, the update law may be: F = — a, which can evaluate the effectiveness of the algorithm. By using this iterative learning control algorithm, the initial user-inputted data 421 may or may not be precise. Rather, in some embodiments, the control algorithm 1103 can compensate for imprecision in the user-inputted data 421 by sensing the forces and making adjustments to the one or more end effectors 305. Accordingly, over time, the control algorithm 1103 will reduce errors between a desired force profile and an actual force profile.

[0089] FIG. 12 illustrates a relationship between time and a force sensed by the sensor 405 for a given operational cycle. The x-axis (e.g., horizontal axis) represents time (e.g., in seconds) while the y-axis (e.g., vertical axis) represents the force (e.g., in Newtons “N”) sensed by the sensor 405. A first line 1201 represents the time versus force sensed for a first operational cycle. A second line 1203 represents the time versus force sensed for a second operational cycle which follows the first operational cycle. A third line 1205 represents the time versus force sensed for a third operational cycle which follows the second operational cycle. A fourth line 1207 represents the time versus force sensed for a fourth operational cycle which follows the third operational cycle. In some embodiments, the first operational cycle occurs without any adjustments or corrections made during the cycle. Following the first operational cycle, an adjustment to a speed and path of the one or more end effectors 305 is made based on the force sensed during the first operational cycle. The second operational cycle represented by the second line 1203 follows a path that is based on the adjustment from the first operational cycle. Following the second operational cycle, another adjustment to a speed and path of the one or more end effectors 305 is made based on the force sensed during the second operational cycle. The third operational cycle represented by the third line 1205 follows a path that is based on the adjustment from the second operational cycle. Following the third operational cycle, another adjustment to a speed and path of the one or more end effectors 305 is made based on the force sensed during the third operational cycle. The fourth operational cycle represented by the fourth line 1207 follows a path that is based on the adjustment from the third operational cycle.

[0090] In some embodiments, the first operational cycle, represented by the first line 1201, experiences the largest force discrepancy, with the force discrepancy increasing over time from about 15 N at 0 seconds to about -60 N at 401 seconds. The second operational cycle, represented by the second line 1203, experiences the second largest force discrepancy, with the force discrepancy increasing over time from about 15 N at 0 seconds to about -35 N at 401 seconds. The third operational cycle, represented by the third line 1205, experiences the third largest force discrepancy, with the force discrepancy increasing over time from about 15 N at 0 seconds to about -20 N at 401 seconds. The fourth operational cycle, represented by the fourth line 1207, experiences the smallest force discrepancy, with the force discrepancy increasing over time from about 15 N at 0 seconds to about -5 N at 401 seconds. Accordingly, after each operational cycle, a correction to the speed and path of the one or more end effectors 305 may be made, with the correction based on the forces sensed during the most recently completed operational cycle. Each subsequent operational cycle can achieve a smaller force discrepancy, thus indicating that the control algorithm 1103 of FIG. 11 can improve the speed and/or path of the one or more end effectors 305 to more closely match a speed and/or path of the glass ribbon 103.

[0091] The glass manufacturing apparatus 100 can provide several benefits. For example, by adjusting the speed and/or path of the one or more end effectors 305 after an operational cycle as opposed to in real-time, the demand for data acquisition and computing power may be reduced while improvements in force reduction between the one or more end effectors 305 and the glass ribbon 103 may still be improved. In addition, the ribbon velocity 507 can be quantified by correlating the ribbon velocity 507 to the robot velocity (e.g., the first robot velocity 505, the second robot velocity 509, etc.) when a magnitude of the force sensed by the sensor 405 is within the predetermined value. Once the magnitude of the ribbon velocity 507 is known, a parameter of the glass ribbon 103, for example, a length of the glass ribbon 103, can be adjusted to compensate for the ribbon velocity 507 such that ribbon portions of the glass ribbon 103 can comprise the same length. In some embodiments, the ribbon velocity 507 may vary over time, such as, for example, due to wear of the pulling roll assembly 158 and a gradual reduction in diameter of the pulling roll assembly 158. These variances in the ribbon velocity 507 can be compensated for with the control assembly 409, thus providing for a matching speed and/or travel path of the one or more end effectors 305 and the glass ribbon 103. Further, in some embodiments, the time to reduce the force sensed by the sensor 405 from exceeding the predetermined value to being within the predetermined value may be fast, for example, within a second. For example, in less than a second, the sensor 405 can sense that a magnitude of the force exceeds the predetermined value, which can trigger an adjustment to the speed or path of the one or more end effectors 305, thus providing for the force to revert back to nearly zero (e.g., within the predetermined value).

[0092] Embodiments and the functional operations described herein can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments described herein can be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a tangible program carrier for execution by, or to control the operation of, data processing apparatus. The tangible program carrier can be a computer readable medium. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, or a combination of one or more of them.

[0093] The term “processor” or “controller” can encompass all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The processor can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them.

[0094] A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, or declarative or procedural languages, and it can be deployed in any form, including as a standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network. [0095] The processes described herein can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit) to name a few.

[0096] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random-access memory or both. The essential elements of a computer are a processor for performing instructions and one or more data memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Moreover, a computer can be embedded in another device, e.g., a mobile telephone, a personal digital assistant (PDA), to name just a few.

[0097] Computer readable media suitable for storing computer program instructions and data include all forms data memory including nonvolatile memory, media and memory devices, including by way of exemplary semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD- ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0098] To provide for interaction with a user, embodiments described herein can be implemented on a computer comprising a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, and the like for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, or a touch screen by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, input from the user can be received in any form, including acoustic, speech, or tactile input. [0099] Embodiments described herein can be implemented in a computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front end component, e.g., a client computer comprising a graphical user interface or a Web browser through which a user can interact with implementations of the subject matter described herein, or any combination of one or more such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Embodiments of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.

[00100] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and comprising a client-server relationship to each other.

[00101] It should be understood that while various embodiments have been described in detail relative to certain illustrative and specific examples thereof, the present disclosure should not be considered limited to such, as numerous modifications and combinations of the disclosed features are possible without departing from the scope of the following claims.