Patent Publication Number: US-11384790-B2

Title: Flexural pivot

Description:
RELATED APPLICATIONS 
     This is a divisional application of U.S. application Ser. No. 15/448,538, filed Mar. 2, 2017, entitled “Flexural Pivot”, which is incorporated by reference in its entirety herein. 
    
    
     BACKGROUND 
     Flexural pivots are devices that permit mechanical members to pivot about a common axis relative to each other through a limited angle range. 
     Because angular motion is accomplished through flexing of elastic flexural elements, rather than contact surface displacement, flexural pivots operate without friction and thus without a need for lubrication. Flexural pivots can therefore be a substitute for bearings in applications where friction and/or the need for lubrication are concerns. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention; and, wherein: 
         FIG. 1A  is an illustration of a flexural pivot in accordance with an example of the present disclosure. 
         FIG. 1B  is an exploded view of the flexural pivot of  FIG. 1A . 
         FIG. 2  illustrates a flexible blade unit of the flexural pivot of  FIGS. 1A  and  1 B. 
         FIG. 3  illustrates a first flexure support member of the flexural pivot of  FIGS. 1A and 1B . 
         FIG. 4  illustrates a second flexure support member of the flexural pivot of  FIGS. 1A and 1B . 
         FIG. 5  illustrates a third flexure support member of the flexural pivot of  FIGS. 1A and 1B . 
         FIG. 6A  is an illustration of a flexural pivot manufacturing system in accordance with an example of the present disclosure. 
         FIG. 6B  is an exploded view of the flexural pivot manufacturing system of  FIG. 6A . 
     
    
    
     Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. 
     DETAILED DESCRIPTION 
     As used herein, the term “substantially” refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, an object that is “substantially” enclosed would mean that the object is either completely enclosed or nearly completely enclosed. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context. However, generally speaking the nearness of completion will be so as to have the same overall result as if absolute and total completion were obtained. The use of “substantially” is equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result. 
     As used herein, “adjacent” refers to the proximity of two structures or elements. Particularly, elements that are identified as being “adjacent” may be either abutting or connected. Such elements may also be near or close to each other without necessarily contacting each other. The exact degree of proximity may in some cases depend on the specific context. 
     An initial overview of the inventive concepts is provided below and then specific examples are described in further detail later. This initial summary is intended to aid readers in understanding the examples more quickly, but is not intended to identify key features or essential features of the examples, nor is it intended to limit the scope of the claimed subject matter. 
     A variety of flexural pivots are commercially available for variety of applications. Common problems with typical commercial off-the-shelf (COTS) flexural pivots that have brazed joints are repeatable performance and reliability, particularly where high performance and durability are required for the application. This may be due to the difficulty in manufacturing flexural pivots in a commercially viable manner. Additionally, applications that require relatively large angular ranges of motion may cause stresses that exceed the strength of COTS flexural pivots, often resulting in brazed joint failures. Thus, it is desirable to develop a flexural pivot design that provides high performance, large angular travel, and reliability while being relatively simple and cost-effective to produce. 
     Accordingly, a flexural pivot is disclosed with brazed joints that can provide high performance, large range of motion, and reliability and that is readily able to be manufactured. The flexural pivot can include a plurality of flexure support members, each flexure support member having a plurality of flexure openings and a plurality of wells each in fluid communication with a respective flexure opening. The flexural pivot can also include at least one flexure to rotatably couple the plurality of flexure support members to one another. The at least one flexure can have first and second flexible blades arranged in a cross configuration. The first and second flexible blades can be disposed in the flexure openings of the flexure support members, and braze material or other coupling material (e.g. an epoxy or other adhesive) deposited in the flexure openings can couple the first and second flexible blades to the flexure support members. 
     In one aspect, a flexural pivot precursor is disclosed. The flexural pivot precursor can comprise a plurality of flexure support members, each flexure support member having a plurality of flexure openings and a plurality of wells each in fluid communication with a respective flexure opening. The flexural pivot precursor can also include at least one flexure to rotatably couple the plurality of flexure support members to one another. The at least one flexure can have first and second flexible blades arranged in a cross configuration. The first and second flexible blades can be disposed in the flexure openings of the flexure support members. 
     A flexural pivot manufacturing system is also disclosed. The system can comprise a fixture having a bottom support and a top support coupled to the bottom support. The system can also comprise a plurality of flexural pivot support member workpieces coupled to the fixture. The plurality of flexural pivot support member workpieces can include a first flexural pivot support member workpiece supported by and coupled to the bottom support, and a second flexural pivot support member workpiece supported by and coupled to the top support. The top and bottom supports can facilitate formation of flexure openings and wells in fluid communication with the flexure openings extending into ends of the flexural pivot support member workpieces to form flexural pivot flexure support members. The top and bottom supports can also facilitate disposing at least one flexure in the flexure openings. The at least one flexure can have first and second flexible blades arranged in a cross configuration. In addition, the top and bottom supports can facilitate disposing braze or other coupling material in the wells to couple the at least one flexure to the flexural pivot flexure support members to provide for rotational movement of the flexural pivot flexure support members relative to one another. 
     In addition, a method for making a flexural pivot is disclosed. The method can comprise coupling a plurality of flexural pivot support member workpieces to a fixture, wherein a first flexural pivot support member workpiece is coupled to a bottom support of the fixture, and a second flexural pivot support member workpiece is coupled to a top support of the fixture. The method can also comprise coupling the top and bottom support to one another. The method can further comprise forming flexure openings and wells in fluid communication with the flexure openings extending into ends of the flexural pivot support member workpieces to form a plurality of flexural pivot flexure support members. The method can even further comprise disposing at least one flexure in the flexure openings of the plurality of flexural pivot flexure support members, wherein the at least one flexure has first and second flexible blades arranged in a cross configuration. The method can still further comprise disposing coupling material in the wells. Additionally, the method can comprise heating the coupling material sufficient to cause the coupling material to flow into the flexure openings to couple the at least one flexure to the flexural pivot flexure support members and thereby rotatably couple the plurality of flexural pivot flexure support members to one another. With respect to the coupling of the at least one flexure to the flexural pivot flexure support members, the method can alternatively comprise disposing an epoxy or other adhesive in the wells, wherein the epoxy or other adhesive comprises a viscosity sufficient to facilitate wicking of the epoxy or other adhesive into the flexure openings via capillary action. 
     One example of a flexural pivot  100  is illustrated in  FIGS. 1A and 1B . The flexural pivot  100  can comprise flexure support members rotatably coupled to one another. For example, the flexural pivot  100  can include a first flexure support member  110 , a second flexure support member  120  rotatably coupled to the first flexure support member  110  for relative rotation about a first axis  101 , and a third flexure support member  130  rotatably coupled to the second flexure support member  120  for relative rotation about a second axis  102 . The axes  101 ,  102  can be orthogonal. Although three flexure support members  110 ,  120 ,  130  are illustrated, it should be recognized that a flexural pivot  100  can include only two flexure support members coupled to one another for relative rotation about only a single axis. 
     The flexural pivot  100  can be coupled to external structures to facilitate relative rotation of the structures about the first and second axes  101 ,  102 . For example, the flexural pivot  100  can be coupled to and utilized with fast steering mirrors, which are commonly used in electro-optical sensors, directed energy systems, long range laser communications systems, telescopes, or other precision optics applications, and therefore may be included in laboratory-based systems, airborne line of sight stabilization systems, satellites, cameras, etc. Thus, one structure can be an optical bench of an electro-optical sensor, and the other structure can be a mirror. The external structures can be coupled to the first and third flexure support members  110 ,  130  utilizing coupling interfaces such as openings or holes  103  (which can be threaded), slots, pins, studs, and other coupling interfaces. 
     The flexural pivot  100  can include flexures  140   a - d  (i.e., cross blade flexures) rotatably coupling the first, second and third flexure support members  110 ,  120 ,  130  to one another. For example, the flexures  140   a - b  can rotatably couple the first and second flexure support members  110 ,  120  to one another, and the flexures  140   c - d  can rotatably couple the second and third flexure support members  120 ,  130  to one another. Thus, the first and second flexure support members  110 ,  120  can move relative to one another about the first axis  101 , and the second and third flexure support members  120 ,  130  can move relative to one another about the second axis  102 , which can provide relative rotation of the first and third flexure support members  110 ,  130  about two axes or in two degrees of freedom. Two or more flexures can be utilized for a given axis to provide stability for the flexure support members. The second flexure support member  120  moves in only a single degree of freedom with respect to each of the first and third flexure support members  110 ,  130 . The second flexure support member  120  may be referred to as a coupler due to its intermediate relationship with respect to the first and third flexure support members  110 ,  130  and function coupling the two-axis rotational movement of the flexural pivot  100 . In one aspect, the flexural pivot  100  can provide a frictionless pivot coupling between two bodies (i.e., external structures) that can support significant loads during high accelerations and allow large angular travel. In addition, the flexural pivot  100  can be designed such that the masses of all the moving parts are balanced at the same center of gravity. For example, the second flexure support member  120  or coupler can be configured so its center of gravity is at the intersection of both the first and second pivot axes  101 ,  102 , which allows its weight to not affect the balancing of the supported or moving mass in both axes. 
     Each flexure  140   a - d  can have two or more flexible blades  141  arranged in a cross configuration. For example, the flexible blades  141  can have a C-shape or configuration. The flexible blades  141  can be oriented with the open sides of the C-shapes facing and oriented about 90 degrees relative to one another to achieve the cross blade configuration. A flexible blade  141  is shown isolated in  FIG. 2 . The flexible blades  141  can have any suitable dimension, as the principles disclosed herein provide flexural pivot components that are scalable to accommodate a wide range of sizes and applications. In one example, a flexural pivot  100  can have an overall size dimension (e.g., length and/or width) of 1.86 inches, and the flexible blades  141  can have a thickness of 0.012 inches. The flexible blades  141  can be made of any suitable material. In some examples, the flexible blade  141  can be made of materials having relatively high yield and fatigue strength, such as steel (e.g., high-carbon spring stainless steel), or titanium (e.g., 6Al-4V). 
     Each of the first, second and third flexure support members  110 ,  120 ,  130  can have flexure openings  150 ,  151 , which can be configured as slots to receive the flexible blades  141 . The flexure openings  150 ,  151  can extend into ends of the first, second and third flexure support members  110 ,  120 ,  130 . In addition, each of the first, second and third flexure support members  110 ,  120 ,  130  can have wells  152 ,  153  (e.g., braze or adhesive wells) in fluid communication with the flexure openings  150 ,  151  to facilitate coupling the flexible members  141  to the flexure support members  110 ,  120 ,  130 . Braze material or another type of coupling material (e.g., epoxy or other adhesive) (not shown) can be disposed in the wells  152 ,  153 . A braze material can be heated and caused to flow from the wells  152 ,  153  into the flexure openings  150 ,  151  about the flexible members  141  to couple the flexible members  141  to the first, second and third flexure support members  110 ,  120 ,  130 . For clarity, flexure openings  150 ,  151  and wells  152 ,  153  of the first, second and third flexure support members  110 ,  120 ,  130  are only identified on portions of the second and third flexure support members  120 ,  130  in  FIGS. 1A and/or 1B . These features are shown in  FIGS. 3-5  and identified with the same reference numbers associated with each individually illustrated flexure support member. Using an epoxy or other adhesive to couple the flexible members  141  to the first, second and third flexure support members  110 ,  120 ,  130 , the adhesive can be selected as having a sufficient viscosity to facilitate wicking of the adhesive into the flexure openings  150 ,  151  via capillary action. Although it is contemplated that various coupling materials can be used, the following detailed description and the examples presented will be illustrated using a braze material as the example coupling material. However, this is not intended to be limiting in any way. 
     The wells  152 ,  153  can be located at ends of the flexure openings  150 ,  151  (e.g., radially outward relative to the flexure openings  150 ,  151 ). This can locate the wells  152 ,  153  proximate to or disposed about portions of the flexible blades  141  that are disposed in the flexure openings  150 ,  151  to facilitate coupling the flexible blades  141  to the first, second and third flexure support members  110 ,  120 ,  130 . The flexible blades  141  can be disposed in the flexure openings  150 ,  151 , which can be configured as slots, such that side walls of the flexure openings  150 ,  151  are disposed on opposite sides of coupling portions  142   a ,  142   b  of the flexible blades  141 . For example, as shown in  FIG. 1B , a flexible blade  141  can be disposed in the flexure opening  150  of the third flexure support member  130 , such that side walls of the flexure opening  150  are disposed on opposite sides of a coupling portion  142   a  of the blade. In addition, the same flexible blade  141  can be disposed in the flexure opening  150  of the second flexure support member  120 , such that side walls of the flexure opening  150  are disposed on opposite sides of a coupling portion  142   b  of the blade  141 . Each of the flexible blades  141  can be similarly disposed in the other flexure openings  150 ,  151  of the flexure support members  110 ,  120 ,  130 . In some embodiments, the flexible blades  141  can extend at least partially into the wells  152 ,  153 . 
     The wells  152 ,  153  can have any suitable shape or configuration. For example, the wells  152 ,  153  can comprise cylindrical openings oriented to extend along the radially outward ends of the flexure openings  150 ,  151  or along ends  143   a ,  143   b  of the flexible blades  141 . In addition, the flexure openings  150 ,  151  can be configured to facilitate a brazed coupling with the flexible blades  141  while maintaining braze material within the flexure openings  150 ,  151  away from the free length or bending portion  144  between the coupling portions  142   a ,  142   b  of the flexible blades  141 . For example, the flexure openings  150 ,  151  can “neck down” or narrow away from the wells  152 ,  153 . This geometry of the flexure openings  150 ,  151  combined with the presence of the flexible blade  141  can capture or limit the flow or capillary action of braze material away from the wells  152 ,  153 . The side walls of the flexure openings  150 ,  151  can therefore be configured to maintain or confine the braze material in the flexure openings  150 ,  151  and prevent or limit braze material from contacting the bending portions  144  of the flexible blades  141 . The side walls defining the flexure openings  150 ,  151  can be precisely formed to engage with the blades  141  and accommodate braze material and/or block braze material flow. 
     By brazing or capturing the coupling portions  142   a ,  142   b  of the flexible blade  141  within the flexure openings  150 ,  151  with braze material originating proximate the outside ends  143   a ,  143   b  or edges of the flexible blades  141 , the bending portion  144  between the coupling portions  142   a ,  142   b  of the flexible blades  141  can be precisely controlled, which can provide repeatable and predictable performance of the flexural pivot  100 . In addition, with the braze material being remotely located from the bending portions  144  (i.e., not located at junctions of the bending portions and the flexure support members), braze material is kept away from the bending portions  144  (which are subject to fatigue), and stress concentrations in the bending portions  144  can be reduced or minimized. Thus, angular travel can be increased for the same bending portion length without failure of the blades. In addition, because the bending portion  144  of the blade  141  does not terminate at the braze material, the braze material does not experience bending stress. The flexural performance of the blades  141  are therefore not limited by the braze couplings with the flexure support members  110 ,  120 ,  130 . Although braze material is not illustrated in  FIG. 1A  for clarity in showing certain aspects of the present disclosure, the braze material can be located in the flexure openings  150 ,  151  between the flexible blades  141  and the side walls of the flexure openings  150 ,  151  in the flexure support members  110 ,  120 ,  130 . As illustrated (i.e., without braze material),  FIG. 1A  shows a flexural pivot precursor in accordance with one example of the present disclosure. 
     In one aspect, the bending portions  144  of the flexible blades  141  can be prevented from contacting adjacent components (e.g., another flexible blade  141  and/or a flexure support member  110 ,  120 ,  130  to which the flexible blade  141  is coupled) to facilitate smooth, unrestricted movement of the flexible blades  141  during operation. For example, the bending portions  144  of the flexible blades  141  can be recessed  145 ,  146  on outer sides of the flexible blades  141  to prevent the bending portions  144  from contacting adjacent components. In other words, an outer edge or surface of the bending portion  141  may not be coplanar or flush with the outer edge or surfaces of the coupling portions  142   a ,  142   b . In addition, the flexible blades  141  can have a C-shape or configuration to facilitate arranging two flexible blades  141  in a cross configuration while providing bending portions  144  that are offset from one another. For example, the recess  146  can be much larger than the recess  145 , thus effectively positioning the bending portion  144  laterally offset with respect to the coupling portions  142   a ,  142   b . This configuration can maximize the lateral size of the coupling portions  142   a ,  142   b  to improve coupling integrity with the flexure support members  110 ,  120 ,  130 . As shown in  FIGS. 1A and 1B , the flexible blades  141  can be substantially identical. 
     In one aspect, the first, second and third flexure support members  110 ,  120 ,  130  can include travel stops  159   a ,  159   b  to mechanically limit a rotational range of motion of the flexible blades  141 . The opposing travel stops  159   a ,  159   b  of the flexure support members can be configured to contact one another at the rotational travel limits. The travel stops  159   a ,  159   b  can limit the range of motion to any suitable degree. Typically, the travel stops  159   a ,  159   b  will be configured to prevent excessive bending of the flexible blades  141  that may result in failure (e.g., yielding) of the blades. The travel stops  159   a ,  159   b  can have any suitable configuration or interface surface to contact opposing travel stops. The travel stops  159   a ,  159   b  can be defined at least partially by the outer side surfaces  155 ,  156  of the flexure support members  110 ,  120 ,  130 . 
       FIGS. 6A and 6B  illustrate a flexural pivot manufacturing system  160  in accordance with an example of the present disclosure. The manufacturing system  160  can include a fixture  161  having a bottom support  170  and a top support  180 . The top and bottom supports  180 ,  170  can be configured to facilitate manufacturing and assembly of a flexural pivot, such as the flexural pivot  100  described above. Thus, the manufacturing system  160  can include flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ coupled to the fixture  161 . A complete flexural pivot  100  (excluding braze material) is shown in  FIGS. 6A and 6B  to demonstrate how the fixture  161  can be used to facilitate certain manufacturing and assembly steps in a method for making a flexural pivot  100 . Thus, it should be recognized that flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ can be at any suitable stage of manufacture when the fixture  161  is utilized. The first, second and third flexure support members  110 ,  120 ,  130  can be made of any suitable material, such as titanium or steel. 
     The workpieces  110 ′,  120 ′,  130 ′ for manufacturing the three flexure support members  110 ,  120 ,  130  can be coupled to and supported by the fixture  161 . For example, the flexural pivot support member workpiece  110 ′ that will form the first flexure support member  110  can be supported by and coupled to the top support  180 . The flexural pivot support member workpiece  130 ′ that will form the third flexure support member  130  can be supported by and coupled to the bottom support  170 . The flexural pivot support member workpiece  120 ′ that will form the second flexural pivot flexure support member  120  can be disposed between the other flexural pivot support member workpieces  110 ′,  130 ′. The workpiece  120 ′ can be supported by and coupled to the top support  180  and/or the bottom support  170 . In the illustrated example, the flexural pivot support member workpiece  120 ′ that will form the second flexural pivot flexure support member  120  is coupled to the bottom support  170 . The flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ can be coupled to the bottom and top supports  170 ,  180  by fasteners  190 ,  191  and/or pins  193 , which can utilize any suitable coupling interface, such as the holes or openings  103  and/or slots. In addition, the bottom and top supports  170 ,  180  can be coupled to one another, such as by fasteners  192  and/or pins  195 . The pins  193 ,  195  can be used to precisely position the top support  180 , the bottom support  170 , and/or the various flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ relative to one another. Pivot flexure interface surfaces of the fixture  161 , such as the interface surface  171  of the bottom support  170 , can be configured to interface with outer (e.g., top and bottom) surfaces of the flexural pivot  100  to mount and support the workpieces  110 ′,  120 ′,  130 ′ during manufacture and assembly. In one aspect, the interface surface  171  can be recessed and sidewalls  172  of the recess can serve as locating or positioning features for the flexure support member workpieces  110 ′,  120 ′,  130 ′. 
     The fixture  161  can include standoff spacers  162  located in the corners of the flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ (i.e., adjacent to sides of the workpieces  110 ′,  120 ′,  130 ′ to position the top and bottom supports  180 ,  170  relative to one another and thereby position the flexural pivot support member workpieces  110 ′,  120 ′,  130 ′ relative to one another. In other words, the standoff spacers  162  can form four legs located in four concave corners of the flexural pivot support member workpieces  110 ′,  120 ′,  130 ′. The standoff spacers  162  can be associated with the top support  180  and/or the bottom support  170 . In the illustrated embodiment, the standoff spaces  162  are associated with the bottom support  170 . The top and bottom supports  180 ,  170  of the fixture  161  can have a plate or block configuration and the standoff spacers  162  can be disposed between the plates or blocks. This fixture configuration of top and bottom supports and standoff spacers  162  can expose the ends of the flexural pivot support member workpieces  110 ′,  120 ′,  130 ′, which can facilitate formation of the flexure openings  150 ,  151  and wells  152 ,  153 , which is described below. 
     The top and bottom supports  180 ,  170  of the fixture  161  can be configured to facilitate formation of the flexure openings  150 ,  151 , described above with respect to  FIGS. 1A-5 , to form the first, second and third flexure support members  110 ,  120 ,  130 . The flexure openings  150 ,  151  can be formed in the workpieces  110 ′,  120 ′,  130 ′ in any suitable manner utilizing any suitable process or combination of processes. For example, the flexure openings  150 ,  151  may be formed in the workpieces  110 ′,  120 ′,  130 ′ by a material removal process, such as machining. Example machining processes include electrical discharge machining (EDM), water jet cutting, milling, etc. A manufacturing process may be selected based on the design objectives, tolerance requirements, cost, etc. A wire EDM process may provide precise machining that can meet tight tolerances and accurately control the flexure openings  150 ,  151 . In one aspect, utilizing a common fixture  161  to support the first, second and third flexure support member workpieces  110 ′,  120 ′,  130 ′ can establish and maintain precision mounting relationships during machining or material removal operations that form the flexure openings  150 ,  151 . Thus, flexure openings  150 ,  151  can be formed in the same fixture setup and at the same time to ensure proper alignment of the flexure openings  150 ,  151  for the flexible blade  141 . This can minimize stresses induced in the blades  141  during assembly due to misalignment, which can provide predictable performance of the flexural pivot  100 . The cuts can be generally in radial directions or, in other words, radially inward and outward relative to the axes of rotation  101 ,  102 . The flexure openings  150 ,  151  and the wells  152 ,  153  can be formed with the same material removal operation. 
     In one aspect, the flexure support members  110 ,  120 ,  130  and the fixture  161  can be designed to allow the assembly-level formation of the flexure openings  150 ,  151  to ensure alignment of the flexure openings  150 ,  151  for assembly with the flexible blades  141 . For example, with the first, second and third flexure support members  110 ,  120 ,  130  in the “assembled” relationship shown in  FIG. 1B , projected profiles of the flexure openings  150 ,  151  and/or the wells  152 ,  153  can extend uninterrupted by adjacent flexure support members in directions parallel to an axis of rotation  101 ,  102  associated with a given flexure  140   a - d . In other words, the geometry of the first, second and third flexure support members  110 ,  120 ,  130  can be such that a line of sight along the flexure openings  150 ,  151  and/or the wells  152 ,  153  for a given flexure support member is not blocked by an adjacent or neighboring flexure support member. This attribute can facilitate manufacture of the flexure support members  110 ,  120 ,  130  coupled together in a common jig or fixture  161 , such as by wire EDM. 
     As an example, the flexure openings  150  in the flexure support member  120 , shown in  FIGS. 1B and 4 , can be made simultaneously with the same manufacturing processes, such as wire EDM. For example, holes in a top cross portion  121  of the flexure support member  120  can be formed (e.g., by drilling) as a starting location for a wire EDM process. The holes can be located across a gap or recess  122  from one another. The same drilling operation can form both holes. The holes can form the wells  152  or the wells can be finish machined by a wire EDM process. The wire for the EDM process can extend through both holes to machine both flexure openings  150  in the top cross portion  121  with the same wire EDM process at the same time. Because the flexure support member  130  is disposed in the assembled position during the machining processes, the flexure support member  130  can include a gap or recess  132  ( FIG. 5 ) that is configured to provide clearance for the drill, wire, etc. used to form the wells  152  and the flexure openings  150  in the top cross portion  121  of the second flexure support member  120 . This sort of clearance relationship between adjacent flexure support members and part features to be machined (e.g., flexure openings and wells) can be replicated throughout the pivot flexure to facilitate simultaneous fixturing and machining of such features in all three of the first, second and third flexure support members  110 ,  120 ,  130 . 
     Cutting or forming the flexure openings  150 ,  151  in the same fixture setup can provide good alignment of the flexure openings. This can reduce or minimize displacement driven stresses in the blades due to misalignment of the flexure openings  150 ,  151 . Once the flexure openings  150 ,  151  have been formed, the flexure support members  110 ,  120 ,  130  can be removed from the fixture  161  and cleaned prior to final assembly where the flexure support members are again secured in the fixture  161  and receive the flexible blades  141  in the flexure openings  150 ,  151 , as described above with respect to  FIGS. 1A-5 . 
     The flexible blades can be manufactured utilizing any suitable process or technique, such as milling, EDM, water jet machining, casting, forging, stamping, photochemical machining (PCM), laser cutting, etc. A wire EDM, PCM, and/or laser cutting process may be utilized to provide accurate control of the part geometry. Final surfaces may be achieved by grinding, honing, polishing, etc. to a desired geometric and/or dimensional tolerance, and/or surface finish. 
     The top and bottom supports  180 ,  170  can be configured to facilitate disposing the flexible blades  141  in the flexure openings  150 ,  151  to rotatably couple the first, second and third flexure support members  110 ,  120 ,  130  to one another. For example, the top and bottom supports (including standoff spacers  162 ) can provide access to ends of the first, second and third flexure support members  110 ,  120 ,  130  to facilitate disposing the flexible blades  141  in the flexure openings  150 ,  151  of the first, second and third flexure support members  110 ,  120 ,  130 . By providing sufficient space about the ends of the flexure support members  110 ,  120 ,  130 , the flexible blades  141  can be inserted into the flexure openings  150 ,  151 . In addition, supporting the first, second and third flexure support members  110 ,  120 ,  130  in the fixture  161  can align the flexure openings  150 ,  151  to facilitate stress-free assembly of the blades  141  prior to brazing. 
     With the flexure support members  110 ,  120 ,  130  fixtured or fixed and the flexible blades  141  disposed in the flexure openings  150 ,  151  as illustrated in  FIGS. 1A and 1B , braze material can be disposed in the wells  152 ,  153  to couple the flexible blades  141  to the flexure support members. This configuration can represent a flexural pivot precursor in accordance with one example of the present disclosure. As described herein, the top and bottom supports  180 ,  170  can be configured to facilitate coupling the flexible blades  141  to the flexure support members  110 ,  120 ,  130 , such as by providing access to the ends of the flexure support members for putting braze material in the wells  152 ,  153 . Any suitable type of braze material in any suitable configuration may be utilized. For example, braze material in wire form can be disposed in the wells  152 ,  153 . Alternatively, braze material in foil form can be disposed about the ends of the flexible blades  141 . In this case, the braze material can be initially located in the wells  152 ,  153  and/or in the flexure openings  150 ,  151 . 
     With braze material disposed in the wells  152 ,  153 , the braze material can be heated sufficiently to cause the braze material to flow (e.g., via capillary action) into the flexure openings  150 ,  151  about the flexible blades  141  to couple the flexible blades to the flexure support members  110 ,  120 ,  130 . The braze material can be heated in any suitable manner, such as by disposing the manufacturing system  160  in a furnace. Thus, the same fixture  161  can be used to support the parts through a brazing operation. Brazing the flexible blades  141  to the flexure support members  110 ,  120 ,  130  in the same fixture  161  can ensure proper alignment of the blades  141  as they are brazed. The flexible blades  141  can therefore be brazed in a single brazing operation with no post-machining necessary. The principles disclosed herein can provide superior brazed connections than that available in COTS flexural pivots. 
     As indicated above, although brazing has been discussed herein as the exemplary way to couple the flexible blades to the flexure support members, such is not intended to be limiting in any way. For example, it is contemplated that the flexible blades can be coupled to the flexure support members using an epoxy or other adhesive, which can be injected into the wells. The epoxy or other adhesive can comprise a viscosity sufficient to cause the epoxy or other adhesive to wick into the flexure openings via capillary action. Those skilled in the art will recognize still other ways that the flexible blades can be coupled to the flexure support members. 
     It is noted that no specific order is required in the methods disclosed herein, though generally in some embodiments, method steps can be carried out sequentially. 
     It is to be understood that the examples set forth herein are not limited to the particular structures, process steps, or materials disclosed, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular examples only and is not intended to be limiting. 
     Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more examples. In the description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of the technology being described. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. 
     While the foregoing examples are illustrative of the principles of the invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts described herein. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.