Patent Publication Number: US-10773902-B2

Title: Adaptive apparatus and system for automated handling of components

Description:
FIELD 
     The present subject matter relates generally to automated manufacturing processes. More particularly, the present subject matter relates to apparatus adaptable for handling components of a variety of shapes. Most particularly, the present subject matter relates to apparatus handling plies of a variety of shapes. 
     BACKGROUND 
     Composite materials are more commonly being used for fabrication of a wide variety of components. For example, carbon fiber composites have high strength and a low weight, making carbon fiber composites attractive for use in aviation applications that require these functionalities. As another example, ceramic matrix composite (CMC) materials can withstand relatively extreme temperatures; accordingly, there is particular interest in replacing components within a combustion gas flow path of a gas turbine engine with components made from CMC materials. Many composite materials, such as carbon fiber and CMC materials, are formed into plies of the composite material, and the composite plies may be laid up to form a preform component that may then undergo various processing cycles to arrive at a component formed from the composite material. 
     Typically, composite components formed from plies of the composite material comprise many composite plies. Each ply is cut from a sheet of the composite material, and then the cut composite plies are laid up to form one or more ply stacks that form the component preform. Often, the cut plies are manually removed from the sheet and manually placed in a ply storage area or manually stacked. Thus, the handling and forming of composite preforms is a time consuming and labor intensive process, which increases the cost of the part. 
     Automating the removal and storage or stacking of the preform process could reduce the part cost and cycle time, as well as reduce employee health concerns from the repetitive nature of ply removal and handling. However, several barriers must be overcome to automate the process of removing composite plies from the sheet of composite material and moving the plies either to a ply storage area or for stacking. For example, to maximize material usage and minimize material waste, a variety of ply shapes and sizes are nested within the composite sheet and then cut prior to removal. Therefore, an automated apparatus for removing the composite plies must be able to adapt to a variety of ply shapes. Also, the automated apparatus must be able to remove the composite ply from the nested plies without displacing the skeleton or remaining composite sheet material. As another example, for large composite plies, the automated apparatus must be able to maintain tension on a ply as it is removed and moved to prevent damaging the ply as it is removed or moved. 
     Accordingly, an automated ply manipulation apparatus would be desirable. For example, a ply manipulation end effector for a robotic arm would be beneficial. In particular, a ply manipulation apparatus with features for automatically adjusting a position of grippers used to pick up a ply would be useful. Additionally, a modular ply manipulation tool for adapting to a plurality of ply shapes and/or sizes would be helpful. 
     BRIEF DESCRIPTION 
     Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     In one exemplary embodiment of the present disclosure, a ply manipulation tool module is provided. The module comprises a first shuttle including a first gripper and a first clamping element, and a second shuttle including a second gripper and a second clamping element. The first and second shuttles move with respect to one another along a path to position the first and second grippers to grip a ply and to position the first and second clamping elements outside the ply. 
     In another exemplary embodiment of the present disclosure, a ply manipulation tool module is provided. The module comprises a lead screw that includes a first lead screw portion and a second lead screw portion. The second lead screw portion has threads opposite to threads of the first lead screw portion. The module further comprises a first nut assembly that includes a first gripper, and a second nut assembly that includes a second gripper. The first nut assembly is threaded on the first lead screw portion and the second nut assembly is threaded on the second lead screw portion such that rotating the first and second lead screw portions moves the first and second nut assemblies toward and away from one another. 
     In a further exemplary embodiment of the present disclosure, a ply manipulation tool assembly. The assembly comprises a first module; a second module; and a longitudinal linear drive member that includes a first longitudinal portion and a second longitudinal portion. Each of the first module and the second module are pivotable relative to the longitudinal linear drive member. Further, each of the first module and the second module include a linear drive member including a first portion and a second portion; a first shuttle including a first gripper; and a second shuttle including a second gripper. The first shuttle is received on the first portion of the linear drive member and the second shuttle is received on the second portion of the linear drive member. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
         FIG. 1  provides a schematic cross-section view of an exemplary gas turbine engine according to various embodiments of the present subject matter. 
         FIG. 2  provides a top view of an arbitrarily shaped composite ply according to an exemplary embodiment of the present subject matter. 
         FIG. 3  provides a schematic view of an automated machine positioned for removing plies cut from a sheet of composite material laid on a cutting table and for moving the removed plies to a suitable location. 
         FIG. 4  provides a top, schematic view of a ply manipulation tool module according to an exemplary embodiment of the present subject matter. 
         FIG. 5A  provides a side, schematic view of a shuttle of the ply manipulation tool module of  FIG. 4  according to an exemplary embodiment of the present subject matter. 
         FIG. 5B  provides a side, schematic view of a tilting gripper assembly of the ply manipulation tool module of  FIG. 4  according to an exemplary embodiment of the present subject matter. 
         FIG. 5C  provides a side, schematic view of the gripper assembly of  FIG. 5B  lifting a ply from a cutting table according to an exemplary embodiment of the present subject matter. 
         FIG. 5D  provides a top, schematic view of a nut assembly of the ply manipulation tool module of  FIG. 4  according to an exemplary embodiment of the present subject matter. 
         FIG. 5E  provides side, schematic views of the ply manipulation tool module of  FIG. 4  according to an exemplary embodiment of the present subject matter. 
         FIG. 5F  provides partial schematic views of the ply manipulation tool module of  FIG. 5E . 
         FIG. 6A  provides a top, schematic view of a ply manipulation tool assembly according to an exemplary embodiment of the present subject matter. 
         FIG. 6B  provides an enlarged view of a portion of the ply manipulation tool assembly of  FIG. 6A  according to an exemplary embodiment of the present subject matter. 
         FIG. 6C  provides an enlarged view of another portion of the ply manipulation tool assembly of  FIG. 6A  according to an exemplary embodiment of the present subject matter. 
         FIG. 6D  provides a top, schematic view of a plurality of ply manipulation tool assemblies coupled to a flange for attaching the assemblies to an automated machine according to an exemplary embodiment of the present subject matter. 
         FIG. 7  provides a top, schematic view of two ply manipulation tool modules, each module attached to a separate robotic arm, according to an exemplary embodiment of the present subject matter. 
         FIG. 8  provides a top, schematic view of a ply manipulation system including two ply manipulation tool assemblies, each assembly attached to a separate robotic arm, according to an exemplary embodiment of the present subject matter. 
         FIG. 9  provides a top, schematic view of a ply manipulation system including a plurality of ply manipulation tool assemblies attached to a plurality of robotic arms according to an exemplary embodiment of the present subject matter. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to present embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the invention. As used herein, the terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “upstream” and “downstream” refer to the relative direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the direction from which the fluid flows and “downstream” refers to the direction to which the fluid flows. 
     Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures,  FIG. 1  is a schematic cross-sectional view of a gas turbine engine in accordance with an exemplary embodiment of the present disclosure. More particularly, for the embodiment of  FIG. 1 , the gas turbine engine is a high-bypass turbofan jet engine  10 , referred to herein as “turbofan engine  10 .” As shown in  FIG. 1 , the turbofan engine  10  defines an axial direction A (extending parallel to a longitudinal centerline  12  provided for reference) and a radial direction R. In general, the turbofan  10  includes a fan section  14  and a core turbine engine  16  disposed downstream from the fan section  14 . 
     The exemplary core turbine engine  16  depicted generally includes a substantially tubular outer casing  18  that defines an annular inlet  20 . The outer casing  18  encases, in serial flow relationship, a compressor section including a booster or low pressure (LP) compressor  22  and a high pressure (HP) compressor  24 ; a combustion section  26 ; a turbine section including a high pressure (HP) turbine  28  and a low pressure (LP) turbine  30 ; and a jet exhaust nozzle section  32 . A high pressure (HP) shaft or spool  34  drivingly connects the HP turbine  28  to the HP compressor  24 . A low pressure (LP) shaft or spool  36  drivingly connects the LP turbine  30  to the LP compressor  22 . 
     For the depicted embodiment, fan section  14  includes a fan  38  having a plurality of fan blades  40  coupled to a disk  42  in a spaced apart manner. As depicted, fan blades  40  extend outward from disk  42  generally along the radial direction R. The fan blades  40  and disk  42  are together rotatable about the longitudinal axis  12  by LP shaft  36 . In some embodiments, a power gear box having a plurality of gears may be included for stepping down the rotational speed of the LP shaft  36  to a more efficient rotational fan speed. 
     Referring still to the exemplary embodiment of  FIG. 1 , disk  42  is covered by rotatable front nacelle  48  aerodynamically contoured to promote an airflow through the plurality of fan blades  40 . Additionally, the exemplary fan section  14  includes an annular fan casing or outer nacelle  50  that circumferentially surrounds the fan  38  and/or at least a portion of the core turbine engine  16 . It should be appreciated that nacelle  50  may be configured to be supported relative to the core turbine engine  16  by a plurality of circumferentially-spaced outlet guide vanes  52 . Moreover, a downstream section  54  of the nacelle  50  may extend over an outer portion of the core turbine engine  16  so as to define a bypass airflow passage  56  therebetween. 
     During operation of the turbofan engine  10 , a volume of air  58  enters turbofan  10  through an associated inlet  60  of the nacelle  50  and/or fan section  14 . As the volume of air  58  passes across fan blades  40 , a first portion of the air  58  as indicated by arrows  62  is directed or routed into the bypass airflow passage  56  and a second portion of the air  58  as indicated by arrows  64  is directed or routed into the LP compressor  22 . The ratio between the first portion of air  62  and the second portion of air  64  is commonly known as a bypass ratio. The pressure of the second portion of air  64  is then increased as it is routed through the high pressure (HP) compressor  24  and into the combustion section  26 , where it is mixed with fuel and burned to provide combustion gases  66 . 
     The combustion gases  66  are routed through the HP turbine  28  where a portion of thermal and/or kinetic energy from the combustion gases  66  is extracted via sequential stages of HP turbine stator vanes  68  that are coupled to the outer casing  18  and HP turbine rotor blades  70  that are coupled to the HP shaft or spool  34 , thus causing the HP shaft or spool  34  to rotate, thereby supporting operation of the HP compressor  24 . The combustion gases  66  are then routed through the LP turbine  30  where a second portion of thermal and kinetic energy is extracted from the combustion gases  66  via sequential stages of LP turbine stator vanes  72  that are coupled to the outer casing  18  and LP turbine rotor blades  74  that are coupled to the LP shaft or spool  36 , thus causing the LP shaft or spool  36  to rotate, thereby supporting operation of the LP compressor  22  and/or rotation of the fan  38 . 
     The combustion gases  66  are subsequently routed through the jet exhaust nozzle section  32  of the core turbine engine  16  to provide propulsive thrust. Simultaneously, the pressure of the first portion of air  62  is substantially increased as the first portion of air  62  is routed through the bypass airflow passage  56  before it is exhausted from a fan nozzle exhaust section  76  of the turbofan  10 , also providing propulsive thrust. The HP turbine  28 , the LP turbine  30 , and the jet exhaust nozzle section  32  at least partially define a hot gas path  78  for routing the combustion gases  66  through the core turbine engine  16 . 
     In some embodiments, components of turbofan engine  10 , particularly components within hot gas path  78 , such as components of combustion section  26 , HP turbine  28 , or LP turbine  30 , may comprise a ceramic matrix composite (CMC) material, which is a non-metallic material having high temperature capability. Exemplary CMC materials may include silicon carbide (SiC), silicon, silica, or alumina matrix materials, or combinations thereof, and ceramic fibers embedded within the matrix material. Additionally or alternatively, components of turbofan engine  10 , such as fan  28 , may comprise a carbon fiber composite material or another composite material, such as a polymer matrix composite (PMC) material. As discussed herein, such composite materials, e.g., CMC, carbon fiber, PMC, etc., are referred to generally as “composite materials” or “composites.” 
     Components made from composite materials may be formed from plies of the composite material that are laid up to form a preform and then processed to produce the final composite component. For example, the composite material may be made as a thin sheet, and plies of the composite material (i.e., composite plies), may be cut from each sheet of composite material. Often, hundreds or thousands of plies are required to form one composite component. Typically, each ply is removed from the sheet of composite material manually, i.e., by human hands, and either manually moved to a ply storage area or moved to a ply layup area, where the composite plies are laid up to form the composite preform. Accordingly, an automated process for removing and moving the composite plies could help reduce fabrication time and cost and also may help reduce errors in the fabrication process. 
     Some composite components utilize plies that may be relatively large in size and/or may have an arbitrary shape. For example, composite plies may have a length that ranges from about 15 centimeters (cm) to about 300 cm and a width that ranges from about 4 cm to about 120 cm. As an example of a component, plies for forming a fan blade  40  of fan  38  may be up to about 150 cm (or 1.5 meters) in length. However, other sizes of plies may be used as well. Further, some plies may have generally geometric shapes, such as generally rectangular, circular, or other another geometric shape, but other plies may have arbitrary shapes. For instance, some plies may be generally non-geometric in shape and may, e.g., comprise one or more bends, curves, and/or angles. An exemplary arbitrarily shaped ply  100 , having a length L, a width W, and an edge or perimeter  101 , is illustrated in  FIG. 2 , but it will be appreciated that the plies  100  used to form a composite component may have any shape and/or size. The shape and size of each ply  100  is arbitrary to the present subject matter, as described in greater detail herein. 
     Referring to  FIG. 3 , in exemplary embodiments of the present subject matter, one or more automated machines  102 , such as a robot or the like, are used to remove composite plies  100  that have been cut from a sheet  104  of composite material that, e.g., is positioned on a cutting table  106 . More particularly, the cutting table  106  may define a first horizontal direction X, a second horizontal direction Y that is perpendicular to the first horizontal direction X, and a vertical direction Z. A sheet  104  of composite material may be positioned on a top surface  105  of the table  106  such that the sheet  104  is generally planar, extending along the first horizontal direction X and the second horizontal direction Y. A plurality of plies  100  may be cut from the sheet  104 , and then automated machine  102  may be used to remove the plies  100  from the sheet  104 . As described herein, the automated machine  102  has one or more features such that the shape and/or size of each ply  100  is immaterial to the machine&#39;s ability to remove the plies  100  from the sheet  104 ; the machine  102  is configured to adapt to the shape and/or size of each ply  100  to remove the ply from the sheet. As such, the plies  100  may be referred to as arbitrarily shaped plies  100 . After removing a ply  100  from the sheet  104  of composite material, the automated machine  102  may move the ply to a ply storage area  108 , to a ply layup area  110 , or to another suitable location away from the sheet  104 . Thus, removing and moving composite plies cut from a sheet of composite material may be an automated process performed by one or more machines rather than a manual process performed by human hands. 
     Further, it should be understood that, although described herein with respect to composite plies  100 , the present subject matter is not limited to manipulation or handling of plies of composite material. Rather, the present subject matter also may be applicable to the handling of other thin objects, which may be formed from a variety of materials, may be rigid, flexible, or semi-rigid, and/or may be an element of a finished component or a finished component. 
     Referring to  FIG. 4 , in one exemplary embodiment, an end effector in the form of a ply manipulation tool is received on a robotic arm  112  of an automated machine  102 . In some embodiments, the end effector ply manipulation tool may be a ply manipulation tool module  200 , but in other embodiments, described in greater detail below, an end effector ply manipulation tool in the form of a ply manipulation tool assembly  250  may be received on robotic arm  112  of automated machine  102 . It will be appreciated that the automated machine  102  may include any suitable control system for controlling the features of the machine without deviating from the scope of the present disclosure. For instance, automated machine  102  may have various suitable configurations and/or control circuitries for removing one or more plies  100  from a sheet  104  of composite material, moving one or more plies  100  to a suitable location, or performing any of the various operations described herein. In the schematic depiction of  FIG. 3 , for example, automated machine  102  includes an articulable robotic arm  112  and module  200  for removing and moving plies  100 , but machine  102  may include any suitable features and components for performing the functions described herein. Further, although described herein with respect to an articulated or 6-axis industrial type robot, it should be appreciated that any suitable robot or automated machine  102  may be used as well. For example, dual arm robots, SCARA robots, Cartesian or gantry robots, parallel or delta robots, cylindrical robots, redundant robots, or the like, as well as mobile robots or manipulators, may be suitable for use with the subject matter described herein. 
     In one embodiment, automated machine  102  includes a control circuit having one or more processors  114  and associated memory device(s) configured to perform a variety of computer-implemented functions (e.g., performing the methods, steps, calculations and the like disclosed herein). As used herein, the term “processor” refers not only to integrated circuits referred to in the art as being included in a computer, but also refers to a controller, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application specific integrated circuit, and other programmable circuits. Additionally, the memory device(s) may generally comprise memory element(s) including, but not limited to, computer readable medium (e.g., random access memory (RAM)), computer readable non-volatile medium (e.g., a flash memory), a floppy disk, a compact disc-read only memory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc (DVD) and/or other suitable memory elements. 
     Such memory device(s) may generally be configured to store suitable computer-readable instructions that, when implemented by the processor(s)  114 , configure the control circuit to perform various functions including, but not limited to, removing one or more plies  100  from the sheet of composite material and moving the one or more plies  100  to a suitable location (e.g., a ply storage area or a ply layup area) or other functions. More particularly, the instructions may configure the control circuit to perform functions such as receiving directly or indirectly signals from one or more sensors (e.g. voltage sensors, current sensors, and/or other sensors) indicative of various input conditions, and/or various other suitable computer-implemented functions, which enable the automated machine(s)  102  to carry out the various functions described herein. An interface can include one or more circuits, terminals, pins, contacts, conductors, or other components for sending and receiving control signals. Moreover, the control circuit may include a sensor interface (e.g., one or more analog-to-digital converters) to permit signals transmitted from any sensors within the system to be converted into signals that can be understood and processed by the processor(s)  114 . 
       FIG. 4  provides a top view of a ply manipulation tool module  200  according to an exemplary embodiment of the present subject matter. The module  200  defines a longitudinal direction L M , a transverse direction T M , and a vertical direction V M  ( FIG. 5A ), which are orthogonal to one another. The module  200  includes a linear drive member  202  having a first portion  204  and a second portion  206 . More specifically, in the exemplary embodiment of  FIG. 4 , the linear drive member  202  is a lead screw  202  that includes a first lead screw portion  204  and a second lead screw portion  206 . The second lead screw portion has threads  210  opposite to threads  208  of the first lead screw portion  204 . The first lead screw portion  204  and the second lead screw portion  206  are aligned with one another along a straight line SL. However, it should be appreciated that, in other embodiments, the linear drive member  202  may have other configurations and need not be a lead screw. For example, the linear drive member  202  may be a rod or the like that supports linear motion of components received thereon. 
     The module  200  further comprises at least one shuttle  212  that moves along a path defined by the linear drive member  202 . In the exemplary embodiment of  FIG. 4 , module  200  includes two shuttles  212  in the form of a first nut assembly  212   a  threaded on the first lead screw portion  204  and a second nut assembly  212   b  threaded on the second lead screw portion  206 . Each nut assembly  212  includes a gripper  216  and a clamping element  218  supported on a platform  220  ( FIG. 5A ), as well as a nut  222  for threading the nut assembly  212  onto the respective lead screw portion  204 ,  206 . More particularly, the first nut assembly  212   a  includes a first gripper  216   a  and a first clamping element  218   a  supported on a first platform  220   a  that is carried on a first nut  222   a . The second nut assembly  212   b  includes a second gripper  216   b  and a second clamping element  218   b  supported on a second platform  220   b  and carried on a second nut  222   b . As with linear drive member  202 , the nut assembly embodiment described herein is provided by way of example only, and it should be understood that each shuttle  212  may have other configurations as well. 
     Grippers  216  of module  200  are used to “grip” plies  100 , e.g., to pick up plies  100  and hold on to plies  100  as the plies are handled, e.g., removed and/or moved from the sheet  104  of composite material. Each gripper  216  may be a vacuum gripper, suction or vacuum cup, needle gripper, adhesive gripper, electrostatic gripper, a plate surface with engravings, or other suitable device. Alternatively, module  200  may utilize a combination of types of grippers  216 , e.g., the gripper  216   a  of first shuttle  212   a  may be different from the gripper  216   b  of second shuttle  212   b . Additionally, each gripper  216  is not limited to a certain shape or a certain size, but the grippers  216  may have a custom shape and/or a custom size, and module  200  may utilize any combination of different shape and size grippers  216 . For instance, each gripper  216  may have the same shape and size, each gripper  216  may have a different shape and size, or some grippers  216  may have the same shape and size. Moreover, although  FIG. 4  illustrates each shuttle  212  having one gripper  216 , other numbers and configurations of grippers  216  may be provided for each assembly  212 . 
     Further, clamping elements  218  may be used, e.g., to hold down the skeleton or remaining material of the sheet  104  of composite material as plies  100  are removed by the module  200 . That is, clamping elements  218  ensure each ply  100  is removed from the sheet  104  of composite material and that no “additional” composite material, i.e., no material other than the ply or plies  100  intended to be removed, is removed from the sheet  104 . As such, each clamping element  218  may be positioned outside an edge or perimeter  101  of the ply  100  to hold down material other than the ply  100  that is being removed. Clamping elements  218 , for example, may comprise cylinders  224  with extendable rods  226  as shown in  FIG. 5A , where the rod  226  extends in a direction opposite a direction in which the module  200  removes ply  100  from the sheet  104  (e.g., the rod  226  extends in a direction opposite of a ply removal direction) such that the rod  226  keeps the skeleton from being removed with the ply  100 . The rod  226  may retract when the ply  100  is removed from sheet  104 , i.e., the clamping element  218  may extend opposite to the ply removal direction until the ply  100  is removed from the sheet  104 . In other embodiments, clamping elements  218  may be any other suitable device for ensuring only the intended ply or plies  100  are removed from the sheet  104  of composite material. In some embodiments of module  200 , a combination of clamping elements  218  may be used, e.g., the clamping element  218  of the first gripping or nut assembly  212   a  may be different from the clamping element  218  of the second gripping or nut assembly  212   b.    
     As depicted in  FIG. 4 , the module  200  further includes an actuator  228 , such as a servomotor, belt drive, lead screw actuator, ball screw actuator, planetary roller screw actuator, rack and pinion actuator, or the like, in operational communication with one or more components for adjusting the positions of the shuttles  212  with respect to one another. In the depicted embodiment, in which the linear drive member  202  is a lead screw, the actuator  228  is in operational communication with the lead screw. The actuator  228  rotates the first lead screw portion  204  and the second lead screw portion  206  of the lead screw  202  to adjust the position of the first nut assembly  212   a  and the second nut assembly  212   b  and thereby adjust the position of each gripper  216  and clamping element  218 . In other embodiments, the actuator  228  may be in operational communication with each shuttle  212  to linearly actuate the assemblies  212  such that the gripper  216   a  and clamping element  218   a  of the first shuttle  212   a  moves with respect to the gripper  216   b  and clamping element  218   b  of the second shuttle  212   b  along the path of the linear drive member  202 . More particularly, a processor  114 , such as described above, may control the actuator  228  to adjust the position of each gripping or nut assembly  212  and thereby adapt the position of grippers  216  and clamping elements  218  according to a shape of a ply  100  for removing the ply  100  from a sheet  104  of composite material. For example, the processor  114  may send one or more signals to actuator  228  to move the first gripping or nut assembly  212   a  to position the first gripper  216   a  near a first portion  101   a  of an edge of ply  100  and to move the second gripping or nut assembly  212   b  to position the second gripper  216   b  near a second portion  101   b  of an edge of ply  100 . The shuttles  212  may move linearly toward and away from one another when actuated, e.g., the first shuttle  212   a  may move along the first portion  204  of linear drive member  202  and the second shuttle  212   b  may move along the second portion  206  of linear drive member  202  such that the shuttles  212  move linearly toward and away from one another. 
     In some embodiments, the processor  114  may automatically control the position of the first shuttle  212   a  and the second shuttle  212   b . For instance, referring to the embodiment of  FIG. 4 , a ply removal pattern may be pre-programmed such that processor  114  stores the positions of the first nut assembly  212   a  and the second nut assembly  212   b  for removing a first ply  100   a , the positions of the first nut assembly  212   a  and the second nut assembly  212   b  for removing a second ply  100   b , and so on for each ply  100  to be removed from a sheet  104  of composite material. Using the pre-programmed positions of the nut assemblies  212 , the processor  114  can control the actuator  228  to reposition the nut assemblies  212  between when the module  200  releases one ply  100  and is positioned to pick up the next ply  100 . In other embodiments, module  200  may include one or more sensors  229  that, e.g., sense and provide inputs to the processor  114  regarding the relative position of each gripper  216 , clamping element  218 , and/or the plies  100  cut in sheet  104 . For example, a sensor  229  may be positioned on each platform  220 , and each sensor  229  may provide inputs to processor  114  regarding the position of an associated gripper  216  with respect to an edge of a ply  100 , the distance of an associated gripper  216  from a reference point, the shape of the ply, or the like. Suitable sensors  229  may include edge sensors, laser distance sensors, color sensors, optical sensors (such as cameras), or any other appropriate sensor. The processor  114  may then use the inputs from each sensor  229  to control the actuator  228  to reposition the nut assemblies  212  such that the position of each gripper  216  and clamping element  218  is adapted to a position for removing the ply  100  according to the ply shape. It will be appreciated that the processor  114  includes any appropriate memory device(s), sensor interface(s), subsystem(s), etc., such as a camera image processing subsystem or the like, for using the inputs from the one or more sensors  229  to control actuator  228 . 
     Thus, the processor  114  may automatically control the gripping or nut assemblies  212  (e.g., by rotating the lead screw portions  204 ,  206  or linearly actuating the shuttles  212  as described) to reposition the grippers  216  for gripping the next ply  100  to be picked up. Such automatic control of the gripper  216  positions may help reduce the time required to remove plies  100  from a sheet  104  of composite material because, e.g., the processor can reposition the gripping or nut assemblies  212  (and thereby the grippers  216 ) for picking up the next ply  100  as the module is moving to pick up the next ply. Accordingly, by the time the module  200  is in place to pick up the next ply  100 , the grippers  216  are in position to engage the next ply. In some embodiments, multiple ply removal patterns may be pre-programmed into the processor  114  or, alternatively, the positions of the gripping or nut assemblies  212  may be sent to the processor  114 , e.g., by an operator or based on inputs from one or more sensors  229 , substantially in real time. 
     The module  200  also comprises a frame  230 . The frame  230  supports various features of the module  200 , such as the linear drive member  202  and/or shuttles  212 , illustrated as lead screw  202 , first nut assembly  212   a , and second nut assembly  212   b  in the exemplary embodiment. As illustrated in  FIG. 4 , the frame  230  may define a perimeter of the module  200 , but in other embodiments, the frame  230  may have a different configuration, i.e., the frame  230  may not extend about or define the perimeter of the module  200 . The frame  230  may have any suitable shape, e.g., a square, rectangular, or other polygonal or appropriate shape, for supporting and/or providing an attachment structure for the various components of the module  200 . 
     As shown in  FIGS. 3 and 4 , the ply manipulation tool module  200  is attached to a robotic arm  112  of the automated machine  102  via a flange  116 . For example, the frame  230  of the module  200  may be coupled to the flange  116  to attach the module  200  to the robotic arm  112 . The flange  116  allows the module  200  to rotate about the robotic arm  112 . That is, a processor  114  of the automated machine  102  may send one or more signals to an actuator  228  to control the angular position of the module  200  with respect to the robotic arm  112  by varying the position of the flange  116 . For example, the flange  116  may rotate with respect to the arm  112 , thereby changing the angular position of the module  200 , which is attached to the flange  116 , with respect to the arm  112 . Moreover, the robotic arm  112  may control the longitudinal, lateral, and vertical location or position of the ply manipulation tool module  200  with respect to the sheet  104  of composite material and the plies  100  to be removed from the sheet  104 . As described above, the processor  114  may automatically control the actuator  228  to reposition the module  200  with respect to the robotic arm according to a pre-programmed ply removal pattern. In other embodiments, one or more sensors  229  may be provided such that processor  114  may automatically control the actuator  228  to reposition or adapt the position of module  200  according to one or more inputs from the sensor(s)  229 , e.g., substantially in real time. 
     Turning to  FIG. 5B , in some embodiments, the sheet  104  of composite material is positioned on a cutting table  106  that places a vacuum on the sheet  104  to hold the sheet in place on the table. As such, a vacuum seal may be formed between the cutting table  106  and plies  100  cut from the sheet  104  of composite material, which may increase the difficulty of removing the plies  100  from the sheet  104  and away from the cutting table  106 . More particularly, the vacuum applied to the sheet  104  may remain on as a ply  100  is removed from the sheet, e.g., to hold the sheet  104  and/or remaining plies  100  in place on the table  106 , and the vacuum may be a relatively strong down force on the sheet  104  and plies  100  cut from the sheet. Thus, to remove the plies  100 , the vacuum seal between the table  106  and the ply or plies  100  being removed from the table may need to be released before attempting to remove the plies  100  from the table  106 . For example, in some embodiments, the vacuum seal may be such that about 400N or more of vertical force may be required to lift a ply straight up from the cutting table  106 , which may unduly strain the module  200  and/or robotic arm  104 . Therefore, releasing the vacuum seal may be desirable to avoid damage to the module  200 , robotic arm  112 , and/or plies  100 . 
     Accordingly, in some embodiments, the module  200  may utilize tilting grippers  232  to help break the vacuum seal and thereby reduce the amount of vertical force required to lift a ply  100  off of the cutting table  106  and remove the ply  100  from the sheet  104  of composite material, while the vacuum force holds the remaining sheet material and/or plies  100  in place on the table. As shown in  FIG. 5B , the first nut assembly  212   a  of module  200  includes a tilting gripper assembly  232  that comprises a cylinder  234 , linkage system  236 , and gripper  216 . In the illustrated exemplary embodiment, the linkage system  236  includes an extendable rod  238  that extends from and retracts into the cylinder  234 ; a main link  240 ; and a pivot link  242 . The main link  240  connects to the rod  238  at a first joint J 1 , the pivot link  242  connects to the main link  240  at a joint J 2 , and the cylinder connects to the nut assembly  212   a  at a third joint J 3 . It should be understood that the tilting gripper assembly  232  may be used with other forms of shuttles  212  and not solely with the nut assemblies  212  of the illustrated embodiment. 
     As shown in  FIG. 5B , when the gripper  216  of tilting gripper assembly  232  is brought down into contact with a ply  100 , the linkage system  236  is arranged such that the gripper  216  is brought down vertically or straight onto the ply  100 . That is, the main link  240  and the pivot link  242  of the linkage system  236  are generally vertical, or aligned generally along the vertical direction V, as the gripper  216  is brought into contact with the ply to grip the ply. To release the vacuum seal between the ply  100  and the cutting table  106 , the rod  238  is retracted into the cylinder  234 , which tilts the main link  240  toward the cylinder  234 . Referring to  FIG. 5C , as the main link  240  tilts toward the cylinder  234 , the main link  240  pulls the pivot link  242  in the direction of the main link  240 , which pulls the gripper  216  in the direction of the main link  240 , i.e., the tilting pivot link  242  tilts the gripper  216  toward the cylinder  234 . As such, an edge  246  of the gripper  216  farthest from the cylinder  234  lifts vertically upward from the table  106 , thereby lifting the ply  100  away from the table and releasing the vacuum seal between the ply  100  and the cutting table  106 , as depicted in  FIG. 5C . After the vacuum seal is released, the module  200  may move slightly vertically, and the rod  238  may be extended from the cylinder  234  to return the main link  240 , pivot link  242 , and gripper  216  to a vertical position to remove the ply  100  from the sheet  104  and away from the cutting table  106 . 
     By releasing the vacuum seal before removing the ply  100  from the sheet  104  of composite material and away from the cutting table  106 , the vertical force required to lift the ply  100  away from the cutting table  106  may be reduced to, e.g., as little as about 10N. Thus, releasing the vacuum seal before vertically lifting the ply  100  can greatly reduce the amount of vertical force required to remove the ply  100  from the sheet  104  of composite material and the cutting table  106 . In some embodiments, a combination of non-tilting grippers  216  and tilting grippers or gripper assemblies  232  may be used in module  200 , i.e., some grippers  216  of the module  200  may be in a fixed position while other grippers  216  may be part of a tilting gripper assembly  232  and thus able to tilt or pivot relative to the vertical direction V. In other embodiments, each gripper  216  of module  200  is part of a gripper assembly  232 , i.e., each gripper of the module is a tilting gripper that tilts or pivots relative to the vertical direction V. 
     Moreover, in some embodiments, multiple or a plurality of clamping elements  218  may be provided on a shuttle  212  of the module  200 . More particularly, more than one clamping element  218  may be supported on a platform  220  of a shuttle  212 . As shown in the exemplary embodiment of  FIG. 5D , the first platform  220   a  of the first nut assembly  212   a  may protrude from one side of the first lead screw portion  204 , on which the first platform  220   a  is received, i.e., the first platform  220   a  may not be centered on the lead screw portion. In such embodiments, a platform guiding rod  244  may be provided, e.g., to help support platform  220  and/or to help guide the platform  220  as the nut assembly  212  is positioned for gripping a ply  100  and clamping down the remaining sheet  104  of composite material. As illustrated in  FIG. 5D , a first platform guiding rod  244   a  may extend generally parallel to the first lead screw portion  204  for guiding and/or supporting first platform  220   a . That is, as the first lead screw portion  204  is rotated as shown by the arrow S, the first platform  220   a  of first nut assembly  212   a  may translate along the first lead screw portion  204  and the first platform guiding rod  244   a  as shown by the arrow N. It will be appreciated that a platform guiding rod  244  may be provided for each platform  220  of module  200 , e.g., a second platform guiding rod  244   b  may extend generally parallel to the second lead screw portion  206  for guiding and/or supporting second platform  220   b.    
     In some embodiments, each of the clamping elements  218  may be individually controlled such that the clamping elements  218  may be selectively utilized in removing plies  100  from the sheet  104  of composite material. That is, not every clamping element  218  need be used to remove a particular ply  100  from the sheet. For example, to remove a narrow ply  100 , one or more clamping elements  218  may be used to hold down the composite material remaining in the sheet  104 , e.g., on either side of the narrow ply. Multiple clamping elements  218  also can help hold down the composite material skeleton where the ply  100  to be removed has a sharp or tight corner. 
     As stated, each of the plurality of clamping elements  218  of a gripping or nut assembly  212  may be selectively activated such that an appropriate number of clamping elements  218  is used for a particular ply configuration. For example, in the exemplary embodiment depicted in  FIG. 5D , the module  200  comprises a first nut assembly  212   a  with three clamping elements  218  arranged in a generally triangular configuration. To remove a first ply  100   a , all three clamping elements  218  may be required to hold down the sheet  104  of composite material as the ply  100  is removed; accordingly, all three clamping elements  218  are activated to hold down the sheet. However, the next ply  100   b  removed by the module  200  may have a different configuration such that only one of the clamping elements  218  of the first nut assembly  212   a  is required to hold down the composite skeleton on the cutting table  106 . Thus, only the one clamping element  218  is activated to hold down the remaining composite material. In other embodiments, the platform  220  may support any suitable number of clamping elements  218 , and the clamping elements  218  may be arranged in any suitable configuration. For example, for a module  200  having two clamping elements  218 , one clamping element  218  may be positioned adjacent one side of the platform  220  and the other clamping element  218  may be positioned adjacent an opposite side of the platform  220 ; the two clamping elements  218  also may be offset from one another such that one clamping element is not directly opposite the other clamping element. As another example, for a module  200  having four clamping elements  218 , the clamping elements  218  may be arranged in a generally rectangular configuration. Of course, other numbers and/or configurations of clamping elements  218  may be used in other embodiments. 
     In still other embodiments, the module  200  may be able to adapt the position of grippers  216  for removing plies  100  from or moving plies  100  to an uneven surface. Referring to  FIG. 3 , as described above, module  200  may be used to remove plies  100  from a generally planar sheet  104  of composite material. Turning to  FIG. 5E , module  200  also may be configured to lay up plies  100  on a layup tool  120  having an uneven layup surface. Further, module  200  may remove plies  100  from a non-planar sheet  104  or from non-planar stack of plies  100 , or module  200  may move plies  100  to a non-planar ply stack. To accommodate handling plies  100  with respect to such uneven or non-planar surfaces, module  200  may include a pivot element  248  that supports pivoting each linear drive member portion  204 ,  206  with respect to the vertical direction V. As shown in the exemplary embodiment of  FIGS. 5E and 5F , the pivot element  248  may pivot a first portion  248   a  about a hinge point P H  to vary the position of first lead screw portion  204 , and thereby the position of first gripper  216   a , with respect to the vertical direction V. The pivot element  248  may pivot a second portion  248   b  about the hinge point P H  to vary the position of second lead screw portion  206 , and thereby the position of second gripper  216   b , with respect to the vertical direction V. It will be appreciated that the figure on the left in both  FIG. 5E  and  FIG. 5F  depicts the grippers  216  in a substantially linear position, while the figure on the left in both  FIG. 5E  and  FIG. 5F  depicts the grippers in a non-linear position. 
     Moreover, as shown in  FIG. 5E , a guide element  247  may be provided on a linear drive member  205  oriented perpendicularly to linear drive member portions  204 ,  206 . A guide line  249   a  extends from guide element  247  to an end of the first linear drive member  204  opposite the pivot element  248 . Similarly, a guide line  249   b  extends from guide element  247  to an end of the second linear drive member  206  opposite the pivot element  248 . An actuator  228  may actuate the guide element  247  such that the guide element  247  travels along the linear drive member  205 , and the motion of the guide element  247  actuates the pivot element  248  to pivot the linear drive member portions  204 ,  206 . The guide lines  249   a ,  249   b  may help support the linear drive member portions  204 ,  206  and help facilitate pivoting of the linear drive member portions  204 ,  206  about the hinge point P H . The pivot element  248  may be, e.g., a gear assembly or the like. In other embodiments, other configurations of module  200  may be used to adjust the positions of grippers  216  to pick up plies  100  from or move plies  100  to uneven or non-planar surfaces. 
     Additionally, the ply manipulation tool module  200  includes features for releasing ply  100  that is gripped by grippers  216  from the grippers  216 . For instance, one or more mechanical devices may separate the ply  100  from the module  200 . The mechanical device or devices may be a part of module  200  or may be separate from the module. In other embodiments, pressurized air or other non-mechanical means may be used to release the ply  100  from the module  200 . Further, in embodiments in which the ply  100  is gripped by one or more vacuum grippers  216 , a vacuum release valve may be included to release the vacuum of the gripper(s)  216 . 
     The ability of the shuttles  212  to move relative to one another also provides a means of releasing the ply  100  from the ply manipulation module  200 . For example, once the ply  100  has been removed from sheet  104  and moved to a suitable location, such as ply storage area  108  or play layup area  110 , the shuttles  212  can be moved toward one another to facilitate the release of the ply  100  from the grippers  216  of the shuttles  212 . In some embodiments, only one shuttle  212  may be moved toward the other shuttle  212 , or the shuttles  212  may be moved in other ways relative to one another to release the ply  100  from the grippers  216 . The ply manipulation module  200  also may include other features for releasing the ply  100 , or whatever component is gripped by the module  200 , from the module  200 . 
     It will be appreciated that the embodiments of module  200  described above may adapt to a variety ply shapes and/or size. As such, module  200  is not limited to removing and/or moving plies  100  having only one shape and/or size. When used with a machine such as automated machine  102  having a robotic arm  112  and a processor  114 , the module  200  may be referred to as a “smart” end-effector, as the module  200  is, e.g., programmable to automatically adapt to various ply configurations. 
     Turning to  FIG. 6A , a top view is provided of a ply manipulation tool assembly  250  according to an exemplary embodiment of the present subject matter. The assembly  250  defines a longitudinal direction L A , a transverse direction T A , and a vertical direction V A , which are orthogonal to one another. As shown in  FIG. 6A , in some embodiments, a ply manipulation tool assembly  250  used with an automated machine  102  may utilize multiple modules  200 . More particularly, the illustrated ply manipulation tool assembly  250  includes a first module  200   a  and a second module  200   b . Each of the first and second modules  200   a ,  200   b  may include the various elements described above with respect to the exemplary embodiments of module  200  shown in  FIG. 4  and  FIGS. 5A through 5F . 
     More specifically, referring to  FIG. 6B , the first module  200   a  includes a linear drive member  202  having a first portion  204  and a second portion  206 , which are shown and described with respect to the exemplary embodiment of first module  200   a  as a lead screw  202  including a first lead screw portion  204  and a second lead screw portion  206 . The second lead screw portion  206  of the first module  200   a  has threads  210  opposite to threads  208  of the first lead screw portion  204  of the first module  200   a . The first lead screw portion  204  and the second lead screw portion  206  of the lead screw  202  of the first module  200   a  are aligned with one another along a straight line SL 1 . The first module  200   a  further includes a first shuttle  212   a , embodied as a first nut assembly  212   a  including a first gripper  216   a  and a first clamping element  218   a  supported on a first platform  220   a  carried on a first nut  222   a . The first module  200   a  also includes a second shuttle  212   b , embodied as a second nut assembly  212   b  including a second gripper  216   b  and a second clamping element  218   b  supported on a second platform  220   b  and carried on a second nut  222   b . The first nut  222   a  of the first nut assembly  212   a  of the first module  200   a  is threaded on the first lead screw portion  204  of the first module  200   a , and the second nut  222   b  of the second nut assembly  212   b  is threaded on the second lead screw portion  206  of the first module  200   a . As such, the first nut assembly  212   a  is received on the first lead screw portion  204  of the first module  200   a , and the second nut assembly  212   b  is received on the second lead screw portion  206  of the first module  200   a . The nut assemblies  212  of the first module  200   a  may linearly move along the respective lead screw portion  204 ,  206  to position each gripper  216  and clamping element  218  in a position for removing a ply  100  from a sheet  104  of composite material. 
     Similarly, as illustrated in  FIG. 6C , the second module  200   b  includes a linear drive member  202  having a first portion  204  and a second portion  206 , which are shown and described with respect to the exemplary embodiment of second module  200   b  as a lead screw  202  including a first lead screw portion  204  and a second lead screw portion  206 . The second lead screw portion  206  of the second module  200   b  has threads  210  opposite to threads  208  of the first lead screw portion  204  of the second module  200   b . The first lead screw portion  204  and the second lead screw portion  206  of the lead screw  202  of the second module  200   b  are aligned with one another along a straight line SL 2 . The second module  200   b  further includes a first shuttle  212   a , embodied as a first nut assembly  212   a  including a first gripper  216   a  and a first clamping element  218   a  supported on a first platform  220   a  that is carried on a first nut  222   a . The second module  200   b  also includes a second shuttle  212   b , embodied as a second nut assembly  212   b  including a second gripper  216   b  and a second clamping element  218   b  supported on a second platform  220   b  that is carried on a second nut  222   b . The first nut assembly  212   a  is received on the first lead screw portion  204  of the second module  200   b , and the second nut assembly  212   b  is received on the second lead screw portion  206  of the second module  200   b . The nut assemblies  212  of the second module  200   b  may translate along the respective lead screw portion  204 ,  206  to position the gripper  216  and clamping element  218  of each nut assembly  212  in a position for removing a ply  100  from a sheet  104  of composite material. 
     Referring back to  FIG. 6A , the first and second modules  200   a ,  200   b  are received on a longitudinal linear drive member  252 , having a first longitudinal portion  254  and a second longitudinal portion  256 . In the exemplary embodiment, the longitudinal linear drive member  252  is a longitudinal lead screw  252  that includes a first longitudinal lead screw portion  254  and a second longitudinal lead screw portion  256 . The second longitudinal lead screw portion  256  has threads  260  opposite to threads  258  of the first longitudinal lead screw portion  254 . The first longitudinal lead screw portion  254  and the second longitudinal lead screw portion  256  are aligned with one another along a straight line SL 3 . 
     The ply manipulation tool assembly  250  further comprises a longitudinal coupling assembly  262  for coupling each module  200  to the longitudinal linear drive member  252  such that the modules  200  may move along a path defined by the longitudinal linear drive member  252 . In the exemplary embodiment of  FIG. 6A , each longitudinal coupling assembly  262  is a longitudinal nut assembly  262 , and a first longitudinal nut assembly  262   a  couples the first module  200   a  to the longitudinal lead screw  252  and a second longitudinal nut assembly  262   b  couples the second module  200   b  to the longitudinal lead screw  252 . Each longitudinal nut assembly  262  includes a platform  264  and a nut  266 . Each platform  264  supports and/or carries the components of the respective longitudinal nut assembly  262 . Each nut  266  is threaded on a longitudinal lead screw portion  254 ,  256  to couple the first module  200   a  and the second module  200   b  to the longitudinal lead screw  252 . More particularly, the first longitudinal nut assembly  262   a  includes a first nut  266   a  that is carried by a first platform  264   a  and is threaded on the first longitudinal lead screw portion  254  to couple the first module  200   a  to the longitudinal lead screw  252 . Similarly, the second longitudinal nut assembly  262   b  includes a second nut  266   b  that is carried by a second platform  264   b  and is threaded on the second longitudinal lead screw portion  256  to couple the second module  200   b  to the longitudinal lead screw  252 . 
     Further, each longitudinal coupling assembly  262  includes a pivot flange  268  supported by the platform  264  such that each module  200  may pivot with respect to the longitudinal linear drive member  252 . In the depicted embodiment, the first longitudinal nut assembly  262   a  includes a first pivot flange  268   a  that enables the first module  200   a  to pivot relative to the first longitudinal lead screw portion  254 . The second longitudinal nut assembly  262   b  includes a second pivot flange  268   b  that enables the second module  200   b  to pivot relative to the second longitudinal lead screw portion  256 . Accordingly, each of the first module  200   a  and the second module  200   b  are pivotable relative to the longitudinal linear drive member  252 , depicted as a longitudinal lead screw  252  in the exemplary embodiment of  FIGS. 6A, 6B, and 6C . 
     As with the ply manipulation tool module  200  described above, the lead screw and nut assembly embodiment described with respect to  FIGS. 6A to 6C  is provided by way of example only. It should be understood that the longitudinal linear drive member  252  and each longitudinal coupling assembly  262  may have other configurations as well. Further, the linear drive member  202  and shuttles  212  of each module  200  of the ply manipulation tool assembly  250  need not be configured as a lead screw and nut assemblies, respectively, but may have other appropriate configurations for adapting the positions of the grippers  216  and clamping elements  218  according to the shape of a ply  100 . 
     It will be appreciated that the ply manipulation tool assembly  250  may include a plurality of actuators  228  that, e.g., control the movement of the shuttles  212  of each module  200 , as well as the movement of each of the longitudinal coupling assemblies  262 . In the exemplary embodiment depicted in  FIG. 6A , five actuators  228  are provided. First, one actuator  228   a  controls the movement of first and second longitudinal nut assemblies  262   a ,  262   b  on the longitudinal lead screw  252 , e.g., by rotating each longitudinal lead screw portion  254 ,  256 . Second, one actuator  228   b  controls the movement of nut assemblies  212  of the first module  200   a  on the lead screw  202  of the first module  200   a , e.g., by rotating each lead screw portion  204 ,  206  of the first module  200   a . Third, one actuator  228   c  controls the pivotable movement of the first module  220   a  relative to the longitudinal lead screw  252 , e.g., by changing an angular position of the first pivot flange  268   a  with respect to the longitudinal lead screw  252 . Fourth, one actuator  228  controls the movement of nut assemblies  212  of the second module  200   b  on the lead screw  202  of the second module  200   b , e.g., by rotating each lead screw portion  204 ,  206  of the second module  200   b . And fifth, one actuator  228  controls the pivotable movement of the second module  200   b  relative to the longitudinal lead screw  252 , e.g., by changing an angular position of the second pivot flange  268   b  with respect to the longitudinal lead screw  252 . 
     In some embodiments, one actuator  228  may be capable of controlling multiple movements; for example, an appropriate actuator  228  may control both the linear movement of the shuttles  212  of the first module  200   a , as well as the pivotable movement of the first module  200   a  relative to the longitudinal linear drive member  252 . Further, it will be understood that a suitable number of actuators  228  may be provided to control the movement of the various elements of the ply manipulation tool assembly  250 . For example, if the assembly  250  includes three modules  200  rather than two modules  200 , an appropriate number of actuators  228  should be provided to control the movement of each movable element of the three modules  200 , as well as the movement of the three modules  200  relative to the longitudinal lead screw  252 . Moreover, an appropriate type of actuator  228 , such as a servomotor, belt drive, lead screw actuator, ball screw actuator, planetary roller screw actuator, rotary actuator, rack and pinion actuator, etc., may be used for each of the multiple movements. In some embodiments, one type of actuator  228 , such as a servomotor or the like, may be able to produce each of the required movements such that each actuator  228  of ply manipulation tool assembly  250  is of the same type. However, in other embodiments, an appropriate combination of types of actuators  228  may be used. 
     Moreover, similar to the ply manipulation tool module  200  described above, the ply manipulation tool assembly  250  comprises at least one processor  114  to control the actuators  228  to adjust the position of each longitudinal coupling assembly  262 , as well as the position of each module  200 , and thereby position grippers  216  and clamping elements  218  in proper positions for removing a ply  100  from a sheet  104  of composite material. In some embodiments, one processor  114  may be utilized to control the one or more actuators  228  of the ply manipulation tool assembly  250 . In other embodiments, a plurality of processors  114  may be provided to control the actuators of the assembly  250 . As previously described, the one or more processors  114  may automatically control the positions of the shuttles  212  of the modules  200 , as well as the positions of the modules  200  with respect to the longitudinal linear drive member  252 . For instance, a ply removal pattern may be pre-programmed such that processor(s)  114  store the positions of the longitudinal coupling assemblies  262  and the shuttles  212  of the first and second modules  200   a ,  200   b  for removing a first ply  100   a , the positions of the assemblies  212 ,  262  for removing a second ply  100   b , and so on for each ply  100  to be removed from a sheet  104  of composite material. In other embodiments, one or more sensors  229  may be provided such that processor  114  may automatically control the actuator(s)  228  to reposition or adapt the position of assemblies  212 ,  262  according to one or more inputs from the sensor(s)  229 , e.g., substantially in real time. Thus, the processor(s)  114  may automatically control the assemblies  212 ,  262  to reposition the grippers  216  for gripping the next ply  100  to be removed, which may, e.g., help reduce the time required to remove plies  100  from a sheet  104  of composite material. In some embodiments, multiple ply removal patterns may be pre-programmed into the processor(s)  114  or, alternatively, the positions of the assemblies  212 ,  262  may be sent to the processor(s)  114 , e.g., by an operator or based on inputs from one or more sensors  229 , substantially in real time. 
     As illustrated in  FIG. 6A , a frame  270  supports various elements of the ply manipulation tool assembly  250 . Similar to the frame  230  of the module  200  illustrated in  FIG. 4 , the frame  270  of the assembly  250  may define a perimeter of the assembly  250 , but in other embodiments, the frame  270  may have a different configuration, i.e., the frame  270  may not extend about or define the perimeter of the ply manipulation tool assembly  250 . It will be appreciated that the frame  270  may have any suitable shape, e.g., a square, rectangular, or other polygonal or appropriate shape, for supporting and/or providing an attachment structure for the various components of the assembly  250 . 
     Further, as shown in  FIG. 6A , the frame  270  of the ply manipulation tool assembly  250  may be coupled to a robotic arm  112  of the automated machine  102  via a flange  116 , thereby attaching the assembly  250  to the robotic arm  112 . The flange  116  allows the ply manipulation tool assembly  250  to rotate about the robotic arm  112 . That is, a processor  114  of the automated machine  102  may send one or more signals to an actuator  228  to control the angular position of the assembly  250  with respect to the robotic arm  112  by varying the position of the flange  116 . For example, the flange  116  may rotate with respect to the arm  112 , thereby changing the angular position of the assembly  250 , which is attached to the flange  116 , with respect to the arm  112 . Moreover, the robotic arm  112  may control the longitudinal, lateral, and vertical position or location of the ply manipulation tool assembly  250  with respect to the sheet  104  of composite material and the plies  100  to be removed from the sheet  104 . 
     Some embodiments of ply manipulation tool assembly  250  may utilize clamping elements  218  comprising a cylinder  224  and extendable rod  226 , as described with respect to  FIG. 5A , where the extendable rod extends as the assembly  250  is lifted vertically to hold the remaining composite material in place such that only the ply  100  gripped by the grippers  216  is removed from the cutting table  106 . Further, in some embodiments, the shuttles  212  of the modules  200  of assembly  250  may utilize tilting gripper assemblies  232  as described above with respect to  FIGS. 5B and 5C . That is, one or more of the grippers  216  of the shuttles  212  of first module  200   a  and/or one or more of the grippers  216  of the shuttles  212  of second module  200   b  may tilt to release a vacuum seal between the ply  100  being removed from a sheet  104  of composite material and the cutting table  106  on which the sheet  104  is laid to cut ply shapes into the sheet  104 . More particularly, as previously described, each tilting gripper assembly  232  may comprise a cylinder  234 , linkage system  236 , and gripper  216 . In exemplary embodiments, the linkage system  236  includes an extendable rod  238  that extends from and retracts into the cylinder  234 ; a main link  240 ; and a pivot link  242 . The main link  240  connects to the rod  238  at a first joint J 1 , the pivot link  242  connects to the main link  240  at a joint J 2 , and the cylinder  234  connects to the nut assembly  212  at a third joint J 3 . After the gripper is brought into contact with a ply  100 , the rod  238  may be retracted into the cylinder  234  to tilt the main link  240  toward the cylinder  234 . As the main link  240  tilts toward the cylinder  234 , the main link  240  pulls the pivot link  242  in the direction of the main link  240 , which pulls the gripper  216  in the direction of the main link  240 , i.e., the tilting pivot link  242  tilts the gripper  216  away from the vertical direction V and toward the cylinder  234 . The edge  246  of gripper  216  farthest from cylinder  234  lifts away from the cutting table  106 , thereby lifting the ply  100  to release the vacuum seal between the ply  100  and the cutting table  106 , as depicted in  FIG. 5C . After the vacuum seal is released, the rod  238  may be extended from the cylinder  234  to return the main link  240 , pivot link  242 , and gripper  216  to a vertical position to fully remove the ply  100  from the sheet  104  and away from the cutting table  106 . Before returning the gripper  216  to the vertical position, the tool assembly  250  may be lifted vertically away from table  106  such that the downward force of the vacuum is not reapplied to the ply  100 . 
     As previously described, releasing the vacuum seal before attempting to remove the ply  100  from the sheet  104  of composite material and away from the cutting table  106  can greatly reduce the vertical force required to lift the ply  100  away from the cutting table  106 . It will be appreciated that, in some embodiments, the ply manipulation tool assembly  250  may utilize a combination of non-tilting grippers  216  and tilting grippers or gripper assemblies  232 , i.e., some grippers  216  of the modules  200  may be in a fixed position while other grippers  216  may be part of a tilting gripper assembly  232  and, thus, may be able to tilt or pivot relative to the vertical direction V. In other embodiments, each gripper  216  of the ply manipulation tool assembly  250  is part of a gripper assembly  232 , i.e., each gripper  216  of the modules  200  is a tilting gripper that tilts or pivots relative to the vertical direction V. 
     Further, as described in greater detail above and illustrated in  FIG. 5D , in some embodiments, multiple clamping elements  218  or a plurality of clamping elements  218  may be provided on one or more of the shuttles  212  of the modules  200  of assembly  250 . As previously described, more than one clamping element  218  may be supported on a platform  220  of a shuttle  212 , and a platform guiding rod  244  may be provided to guide and/or support the platform  220 . In some embodiments, each of the clamping elements  218  may be individually controlled such that the clamping elements  218  may be selectively utilized in removing plies  100  from the sheet  104  of composite material. Each of the plurality of clamping elements  218  of a shuttle  212  may be selectively activated such that an appropriate number of clamping elements  218  is used for removing each ply  100 . 
     Moreover, as described with respect to  FIGS. 5E and 5F , the modules  200  of ply manipulation tool assembly  250  may be able to adapt the position of grippers  216  for removing plies  100  from or moving plies  100  to an uneven surface. For example, one or more modules  200  of assembly  250  may include a hinged frame  246  such that the positions of grippers may pivot with respect to the vertical direction V and thereby adapt to the contour of a ply  100  positioned on an uneven surface or to adapt the contour of the ply  100  for positioning on an uneven surface. As another example, one or more modules  200  of assembly  250  may include vertical positioning assemblies  248  for varying the vertical position of each gripper  216 . Each vertical positioning assembly  248  may include a cylinder  234  and extendable rod  238  arranged to vary the vertical position of a gripper  216  as the rod  238  extends and retracts. Further, the gripper  216  may be pivotally attached to the rod  238  of the assembly  248  such that the gripper  216  may pivot about the rod  238  to adjust to the contour of the ply  100  on which the gripper  216  is positioned. Accordingly, modules  200  may be able to adjust the positions of grippers  216  to pick up plies  100  from or move plies  100  to uneven surfaces. 
     Additionally, as previously described with respect to ply manipulation tool module  200 , the ply manipulation tool assembly  250  may include or be used with one or more features for releasing the ply or plies gripped by the assembly  250  from the assembly. Mechanical or non-mechanical means for releasing the ply or plies as described with respect to module  200  may be used to release the ply or plies from assembly  250 . For instance, the modules  200  of ply manipulation tool assembly  250  may move relative to one another to release a ply gripped by the modules  200 , or the shuttles of a module  200  of the assembly  250  may move relative to one another to release a ply gripped by the module  200  or the assembly  250 . As another example, in embodiments utilizing one or more vacuum grippers  216 , a vacuum release valve may be included to release the vacuum applied by the gripper(s)  216  to grip the ply or plies. Other means for releasing the component or components gripped by the ply manipulation tool assembly  250  may be used as well. 
     Although illustrated in  FIG. 6A  with two modules  200 , the ply manipulation tool assembly  250  may have any suitable number of modules  200 . For example, a ply manipulation tool assembly  250  may comprise a single module  200 , i.e., one module  200  may be received on a longitudinal linear drive member  252 . In other embodiments, an assembly  250  may comprise two, three, four, or more modules  200 . A single frame  270  may support every module  200  of the assembly  250 , or the assembly  250  may comprise multiple frames  270  to support the modules  200  of the assembly  250 . Alternatively or additionally, a module frame  230  may be included with some or all of the modules  200  of assembly  250  to help support the various elements of the assembly  250 . 
       FIG. 6D  provides a top view of an exemplary embodiment of the present subject matter in which multiple ply manipulation tool assemblies  250  are connected to a robotic arm  112  via a flange  116 . More particularly, in the embodiment of  FIG. 6D , two ply manipulation tool assemblies  250  are each connected to a connector  272 . The connector  272  is coupled to the flange  116  to attach the assemblies  250  to the robotic arm  112  of automated machine  102 . In other embodiments, any suitable number of ply manipulation tool assemblies  250  may be connected to connector  272 , which in turn is coupled to a flange  116  to attach the assemblies to an automated machine  102 . As described above, flange  116  allows the angular position of the assemblies  250  to vary with respect to the arm  112 , e.g., processor  116  may send one or more signals to vary the position of flange  116 , thereby altering the position of the attached assemblies  250  with respect to the arm  112 . 
     A ply manipulation tool assembly  250  comprising multiple modules  200  may be helpful in removing complex shaped plies  100  from a sheet  104  of composite material and/or in moving such plies  100 . For instance, some plies  100  used in forming a composite preform may be relatively long and/or wide or may have a shape that includes one or more bends, curves, and/or angles. Further, the same assembly  250  may be used to remove and/or move plies  100  having a variety of shapes, i.e., at least one ply  100  removed and/or moved by assembly  250  may not have the same shape as other plies  100  removed and/or moved by the assembly. As such, the grippers  216  of assembly  250  preferably may be positioned in a multitude of configurations to adapt to a variety of ply shapes. Moreover, one ply manipulation tool assembly  250  may be used to remove and/or move more than one ply  100  at a time. For example, the grippers  216  may be positionable to simultaneously remove two or more separate plies  100  from a sheet  104  of composite material and move the plies  100  to a suitable location. Accordingly, an assembly  250  having a plurality of modules  200  may be adaptable to a variety of ply shapes as well as to simultaneously picking up multiple, separate plies  100 . 
     Referring now to  FIG. 7 , in some embodiments, a ply manipulation tool module  200  may be attached to a robotic arm  112  and another ply manipulation tool module  200  may be attached to another robotic arm  112 , and together, the tool modules  200  attached to the separate robotic arms  112  may pick up a single ply  100 . For instance, as shown in the exemplary embodiment of  FIG. 7 , a first ply manipulation tool module  200   a  is attached to a first robotic arm  112   a  at a first flange  116   a , and a second ply manipulation tool module  200   b  is attached to a second robotic arm  112   b  at a second flange  116   b . Each robotic arm  112  may be independently controlled such that, e.g., the position of the first module  200   a  with respect to the sheet  104  may be independent of the position of the second module  200   b  with respect to the sheet  104 . Further, the angular position of the linear drive member  202  of each module  200  may be independently controlled, i.e., the angular position of the linear drive member  202  of the first module  200   a  may be different from the angular position of the linear drive member  202  of the second module  200   b . It will be appreciated that, in other embodiments, more than two robotic arms  112 , each arm  112  having one or more ply manipulation tool modules  200  attached to the arm, may be used. Moreover, it will be understood that the two or more robotic arms  112  may be part of a single automated machine  102  or one or more of the multiple robotic arms  112  may be a component of a separate machine  102 , e.g., in the embodiment of  FIG. 7 , each arm  112  may be part of a separate automated machine  102 . 
     Using multiple or a plurality of robotic arms  112 , each arm  112  having a ply manipulation tool module  200 , may be particularly useful for removing relatively long composite plies  100  from a sheet  104  of composite material. As an example, as a ply  100  greater than about 100 cm in length is moved, the air resistance on the ply may be such that control over the ply may be lost, which could damage the ply. By using modules  200  on independent robotic arms  112 , tension may be applied to the ply  100  to keep control over the ply, i.e., to ensure the stability of the ply as it is moved. For example, the ply  100  may be vertically lifted by modules  200  and then robotic arms  112  may slightly separate from one another to hold the ply  100  in the tension. Once in tension, the ply  100  may be more easily handled than a ply not held in tension, which can help in moving or otherwise handling the ply as described above. 
     Of course, utilizing multiple robotic arms  112  may be helpful in other situations as well. For example, as shown in  FIG. 8 , a ply manipulation system  280  may comprise a plurality of robotic arms  112 , each robotic arm  112  having a ply manipulation tool assembly  250  with multiple modules  200  attached to the arm via a flange  116 . As such, the ply manipulation system  280  provides a plurality of grippers  216  that are positionable in a plurality of locations. More particularly, because each ply manipulation tool assembly  250  is rotatable about the robotic arm  112  to which the assembly  250  is attached, and the robotic arm  112  can vary the longitudinal, lateral, and vertical location or position of each assembly  250  with respect to the sheet  104  of composite material, the ply manipulation system  280  can adapt its grippers  216  to any of a variety of ply shapes and/or sizes. For example, the ply manipulation system  280  can position its grippers  216  for removal of a ply  100  having a complex shape (e.g., a ply with a sharp bend, a ply with multiple bends, etc.), a relatively long ply  100  (e.g., greater than about 70 cm long), a relatively wide ply  100  (e.g., greater than about 10 cm wide), or the like. In addition, as described above, the ability to move or reposition the grippers  216  relative to one another can assist in releasing a ply  100 , or other component gripped by the ply manipulation system  280 , from the ply manipulation system  280 , although the system  280  may include other features for releasing the ply  100  or other component from the system. 
     In other embodiments, such as the embodiment illustrated in  FIG. 9 , the ply manipulation system  280  may comprise a plurality of robotic arms  112  and each robotic arm  112  includes a plurality of ply manipulation tool assemblies  250  attached to the arm via a flange  116 . For example, as depicted in  FIG. 9 , the ply manipulation system  280  may include a first robotic arm  112   a  having a first flange  116   a  to which is attached two ply manipulation tool assemblies  250 . The system  280  also may include a second robotic arm  112   b  having a second flange  116   b  to which is attached two ply manipulation tool assemblies  250 . Similar to the ply manipulation system  280  described with respect to  FIG. 8 , a system  280  comprising a plurality of ply manipulation tool assemblies  250  attached to a plurality of robotic arms  112  may be useful for manipulating plies  100  having complex shapes and/or for manipulating plies  100  that are relatively large in size. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.