Patent Description:
Manufacturing facilities include platforms to position one or more workers in proximity to a workpiece. The platforms are large enough to hold one or more workers and the tools necessary to complete work on the workpiece. For large workpieces, the platforms are elevated above a floor. The platforms are designed to keep the workers safe while performing the work. This includes positioning the leading edge of the platform in proximity to the work piece. This prevents and/or reduces a gap between the platform and workpiece that could cause a worker to fall through to the floor, or to get their foot trapped which could lead to an injury. This also prevents tools and materials from inadvertently falling through the gap and down to the floor below.

At some facilities, the workpieces are positioned on a mandrel that rotates the workpiece. This is particularly applicable for large workpieces. This allows for the workpiece to rotate past the worker who remains on the platform and can perform work on an entire workpiece. For example, aircraft tooling is often constructed from multiple different large sections. The individual sections are mounted on a mandrel and then rotated to allow a worker to complete work tasks on the entirety of the section without moving from the platform. In one specific example, a fuselage of a large aircraft is constructed from multiple pieces that are each constructed and then subsequently attached together.

An issue with this type of platform is the workpiece may include a complex contoured shape with a varying nominal exterior surface. A work platform with a fixed shape is positioned at the workpiece to support the workers. Because of the shape of the workpiece, a gap is formed between the workpiece and the work platform at one or more rotational positions of the workpiece. The size of the gap can vary depending upon the complex contoured shape of the workpiece.

One current work platform addresses this issue by the platform being constructed from two or more smaller sections. The sections are configured to be manually moved by the workers to position the leading edges at the workpiece at each of the various rotational positions. This requires the workers to move off of the platform, insert safety guards, move the sections of the platform away from the work piece, rotate the work piece while the sections are positioned away, manually move the sections back to the workpiece, and remove the safety guards. Once the platform sections are placed back at the workpiece, the workers can again move onto the platform and begin work. This is a time-consuming process for the workers to move and reposition the platform sections. Further, no work can be performed on the workpiece while the workers are moving the platform sections.

Some current systems have included an automated work platform. Sensors are positioned to detect the size of the gap between the platform and the workpiece. However, the sensors can become dirty or otherwise blocked which prevent their operation. Further, these systems can have difficulty with detecting a size of the gap when irregular details of the workpiece such as small troughs and protrusions that can be positioned on the exterior of the workpiece. These irregular details can cause the sensors to improperly position the platform relative to the workpiece.

<CIT> describes a universal platform and an assembly method of an aircraft using the same. The universal platform includes a plurality of scissor lifts arranged around an aircraft, wherein each of the plural scissor lifts includes a base frame, a support frame located above the base frame, a support table fixedly coupled to an upper portion of the support frame, a plurality of link members axially assembled to be mutually pivoted between the support frame and the base frame, a plurality of hydraulic cylinders coupled to the respective link members and the base frame so as to lift the support frame in upward and downward directions, and a slide member slidably coupled to the support table, and the slide member slides from the support table toward the aircraft so as to allow a worker to work according to height, and there is provided the assembly method of the aircraft using the universal platform.

<CIT> describes a method of making an aircraft. A mandrel is caused to pass through frames carried by a magazine; and as it passes through, the frames are transferred onto the mandrel.

In a first aspect of the presently claimed invention, there is provided a work platform as defined in claim <NUM>.

The sliders may be positioned together with at least one of the lateral edges sliding along a lateral edge of an adjacent one of the sliders.

The platform may comprise a base that supports the sliders, and rails mounted to the base and connected to the sliders with the rails engaged with the sliders for the sliders to move relative to the base.

The platform may comprise a camshaft that is rotated by the one or more motors, cam paths spaced apart along the camshaft with each of the cam paths corresponding to the sectional shape of the workpiece at the cam path, and link members connected to the cam paths and the sliders. The control unit may be configured to maintain the leading edges of the sliders at a constant distance away from the workpiece with the movement of each of the sliders controlled by one of the one or more motors according to a predefined motion profile.

The platform may comprise a mat connected to two or more of the sliders with the sliders being movable relative to the mat.

Two or more of the sliders may move different amounts during rotation of the workpiece.

The work platform may comprise a base and sliders supported by the base and that extend along the workpiece with the sliders located at a different position along the length of the workpiece. The sliders may be movable relative to the base to adjust a distance of leading edges of the sliders relative to the workpiece. One or more motors may move the sliders relative to the base. The movement of each of the sliders may be a function of the sectional shape of the workpiece at the position of the slider along the length of the workpiece and a rotational position of the workpiece.

The sliders may comprise a leading edge that is positioned towards the workpiece and lateral edges with the sliders being aligned together with the lateral edges of adjacent ones of the sliders in proximity to form a continuous floor.

The work platform may comprise cams spaced apart and positioned at the sliders with the cams comprising a cam path that corresponds to the sectional shape of the workpiece where the cam is located along the length of the workpiece, and link members that extend between cams and the sliders.

The work platform may comprise a control unit configured to control the one or more motors to synchronize the movement of the sliders with the rotational position of the workpiece.

The sliders may form a floor of the work platform.

The work platform may comprise a mat that extends over and is connected to two or more of the sliders with the sliders being movable relative to the mat.

In a second aspect of the presently claimed invention, there is provided a method as defined in claim <NUM>.

The method may further comprise operatively connecting each of the sliders to a cam that comprises a cam path that corresponds to the sectional shape of the workpiece at the cam; and rotating each of the cams in a synchronized manner with the workpiece and laterally moving the sliders.

The method may further comprise moving two or more the sliders different amounts while rotating the workpiece between a first rotational position and a second rotational position.

The method may further comprise moving one or more of the sliders and concurrently maintaining a position of one or more of the sliders.

The features, functions and advantages that have been discussed can be achieved independently in various aspects or may be combined in yet other aspects, insofar as they fall within the scope of the appended claims, further details oof which can be seen with reference to the following description and the drawings.

The present application is directed to a work platform <NUM> as illustrated in <FIG> configured to support one or more workers in proximity to a workpiece <NUM>. The work platform <NUM> includes sliders <NUM> that are aligned along the length L of the workpiece <NUM>. The sliders <NUM> are movable towards and away from the workpiece <NUM> as illustrated in arrow A to maintain the leading edges <NUM> at the workpiece <NUM> to minimize and/or eliminate gaps. The sliders <NUM> are individually movable with a position of each of the sliders <NUM> being a function of the sectional shape of the workpiece <NUM> where the slider <NUM> is positioned and the rotational position of the workpiece <NUM>.

The work platform <NUM> provides for the leading edge <NUM> of the sliders <NUM> to remain at the workpiece <NUM> during rotation of the workpiece <NUM>. The workpiece <NUM> has a complex contoured shape along the length L. As illustrated in <FIG>, this complex sectional shape has a non-constant cross section with a variable radius R measured between the centerline C and the nominal exterior surface <NUM>. The lateral movement of the sliders <NUM> adjusts the position of the leading edges <NUM> relative to the workpiece <NUM> to prevent and/or reduce the size of a gap formed between the work platform <NUM> and workpiece <NUM>. This reduction or elimination in the gap provides for a safe work environment for workers on the work platform <NUM>.

<FIG> illustrate the sliders <NUM> of the work platform <NUM> adjusting to accommodate the complex contoured shape of the workpiece <NUM>. The work platform <NUM> is positioned with the leading edges <NUM> of the sliders <NUM> positioned towards the workpiece <NUM>. In one example, the leading edges <NUM> are positioned against the exterior surface <NUM> of the workpiece <NUM>. In another example, the leading edges <NUM> are positioned in close proximity, such as within <NUM>,<NUM> (<NUM> inches) of the exterior surface <NUM>.

Each of the sliders <NUM> is aligned at a different location along the length L of the workpiece <NUM>. The movement of each slider <NUM> is a function of the sectional shape of the workpiece <NUM> at the location of the slider <NUM> and a rotational position of the workpiece <NUM>. <FIG> illustrates the workpiece <NUM> at a first rotational position. Each of the sliders <NUM> is adjusted with the leading edges <NUM> positioned at the workpiece <NUM>.

As illustrated in <FIG>, the workpiece <NUM> has rotated in the direction of arrow R about the center point C to a different second rotational position relative to the work platform <NUM>. This different rotational position provides for a different point along the exterior surface <NUM> to be aligned with the sliders <NUM>. Due to the complex contoured shape of the workpiece <NUM>, one or more of the sliders <NUM> has laterally moved towards or away from the workpiece <NUM> to match the sectional shape where the slider <NUM> is positioned along the length L. Each of the sliders <NUM> moves separately from the other sliders <NUM>. Thus, the amount of movement of each slider <NUM> is a function of the shape of the workpiece <NUM> at the location of the slider <NUM> and the rotational position of the workpiece <NUM>. One or more of the sliders <NUM> may not move when the sectional shape of the workpiece <NUM> is constant between the different rotational positions.

<FIG> illustrates the workpiece <NUM> at a third rotational position relative to the work platform <NUM>. Again, one or more of the sliders <NUM> has laterally adjusted relative to the workpiece <NUM> to conform to the sectional shape where the slider <NUM> is located along the length L. In each of the different rotational positions, the leading edges <NUM> of the sliders <NUM> remain at the workpiece <NUM> to eliminate and/or reduce gaps.

The work platform <NUM> can be used to locate workers at various positions relative to the workpiece <NUM>. <FIG> illustrates one example with a pair of work platforms 19a, 19b positioned on opposing sides of a workpiece <NUM>. The work platforms <NUM> are elevated above the floor <NUM> and provide a structure to support one or more workers that are working on the workpiece <NUM>. The work platforms <NUM> are positioned to allow the workers to access the workpiece <NUM> as the workpiece <NUM> is rotated about a centerline C.

The work platform <NUM> can include various lengths. In one example, the workstation <NUM> has a length that matches the length L of the workpiece <NUM>. Other examples include a length that is shorter than the workpiece <NUM>, and a length that is longer than the workpiece <NUM>. The work platform <NUM> can include various numbers of sliders <NUM>. In one example, the sliders <NUM> extend across the entirety of the work platform <NUM>. In another example, the sliders <NUM> are positioned along a limited length of the work platform <NUM>.

<FIG> illustrates a slider <NUM> that includes a leading edge <NUM> that is positioned towards the workpiece <NUM>, an opposing trailing edge <NUM>, and lateral sides <NUM>, <NUM> that extend between the leading and trailing edges <NUM>, <NUM>. <FIG> includes a slider <NUM> with a substantially rectangular shape. Sliders <NUM> can also include various other shapes and sizes. In one example, each of the sliders <NUM> of a work platform <NUM> include the same shape and size. In another example, one or more of the sliders <NUM> includes a different shape and/or size. <FIG> further includes the leading edge <NUM> being flat and perpendicular to the lateral sides <NUM>, <NUM>. Other examples include the leading edge <NUM> having different shapes.

In one example as illustrated in <FIG>, the sliders <NUM> are positioned with one or both of the lateral sides <NUM>, <NUM> contacting against adjacent sliders <NUM>. This spacing forms a continuous floor <NUM> as illustrated in <FIG> without spaces that could cause a trip hazard or provide for a tool to fall through to the floor <NUM> below. In another example, a space is positioned between one or both of the lateral sides <NUM>, <NUM> and the adjacent sliders <NUM>.

The sliders <NUM> can be supported on the work platform <NUM> in a variety of different manners.

<FIG> illustrates the sliders <NUM> being mounted to a top side of a base <NUM>. In this example, the sliders <NUM> form the floor <NUM> on which the workers stand. To ensure the safety of the workers, the movement of the sliders <NUM> as illustrated by arrow A can be relatively small and/or slow to still provide for the floor <NUM> to safely support the workers. <FIG> includes an example in which a mat <NUM> is positioned on a top side of the sliders <NUM>. The mat <NUM> can be attached to one or both of the sliders <NUM> and the base <NUM>. The mat <NUM> can be formed from an elastic material, such as rubber to accommodate the moving sliders <NUM>. The mat <NUM> forms the surface of the floor <NUM> and stretches during movement of the sliders <NUM> such that the workers do not feel the movement. In one example, the mats <NUM> have a rectangular shape and are connected at the corners to adjacent sliders <NUM>. The mats <NUM> have a flexibility to accommodate the differences in movement between the sliders <NUM>. In one specific example, adjacent sliders <NUM> can move a relative difference of about <NUM>,<NUM> (one inch) during the lateral movement.

<FIG> illustrates a portion of a work platform <NUM> with sliders 30a, 30b, 30c positioned on a base <NUM>. A slider is removed from the base <NUM> to illustrate rails <NUM> that are mounted to the base <NUM> and are configured to movably support the sliders <NUM> to provide for the lateral movement. Corresponding rails extend from the bottom of the sliders <NUM> and engage with the rails <NUM>. A mat <NUM> extends over one or more of the sliders <NUM> and forms the floor <NUM>. <FIG> includes just a pair of mats <NUM> attached to the sliders <NUM>, however, additional mats <NUM> would be attached across the sliders <NUM> to form a larger and complete floor <NUM> when the work platform <NUM> is completely constructed.

In another example as illustrated in <FIG>, the sliders <NUM> are positioned below the floor <NUM>. In this example, the sliders <NUM> are positioned below the base <NUM> which forms the floor <NUM>. The top surface of the sliders <NUM> extend the floor <NUM> outward from the base <NUM> towards the workpiece <NUM>.

The sliders <NUM> can be driven in a number of different manners to move laterally for the leading edges <NUM> to remain at the workpiece <NUM>. <FIG> illustrates one example that includes the sliders <NUM> connected to a camshaft <NUM> that is driven by a motor <NUM>. The camshaft <NUM> is positioned in proximity to the sliders <NUM> and includes cams <NUM> spaced apart along the length. A link member <NUM> extends between each of the cams <NUM> and the corresponding slider <NUM>. Each of the link members <NUM> follows a cam path on the corresponding cam <NUM> such that the movement of the slider <NUM> corresponds to the sectional shape of the workpiece <NUM> where the slider <NUM> is located.

The cams <NUM> each include a cam path <NUM> that is followed by the link member <NUM>. The cam path <NUM> can be positioned at various locations on the cam <NUM>. <FIG> illustrates a cam <NUM> having a complex shape with an irregular exterior edge <NUM>. An opening <NUM> extends through the cam <NUM> to receive the camshaft <NUM>. In this example, the cam path <NUM> is positioned inward from the exterior edge <NUM>. <FIG> includes a cam <NUM> with the cam path <NUM> formed at the exterior edge <NUM>.

The link member <NUM> operatively connects the slider <NUM> to the cam path <NUM>. The link member <NUM> includes an elongated shape with a first end <NUM> attached to the cam path <NUM> and the second end <NUM> attached to the slider <NUM>. In one example as illustrated in <FIG>, the first end <NUM> includes a clevis <NUM> that extends on opposing sides of a cam <NUM> and rides within the cam path <NUM>. In another example, the first end <NUM> rides in the cam path <NUM> that is recessed around the exterior edge of the cam <NUM>. In another example, the second end <NUM> is attached to the slider <NUM> at the trailing edge <NUM>. Other examples include an attachment at other points along the slider <NUM>.

The motor <NUM> is connected to and configured to rotate the camshaft <NUM> to provide for the movement of the sliders <NUM> to be synchronized with the workpiece <NUM>. In one example as illustrated in <FIG>, the motor <NUM> is in communication with a motor <NUM> that rotates the workpiece <NUM>. The motors <NUM>, <NUM> are electrically linked to provide for the synchronized movement of the workpiece <NUM> and the sliders <NUM>. In one example, motor <NUM> is attached to a mandrel that extends through the workpiece <NUM>. In another example, a single motor, such as motor <NUM> or motor <NUM>, is mechanically linked to and rotates both the camshaft <NUM> and the mandrel that extends through the workpiece <NUM>.

In one example, a control unit <NUM> provides for the synchronized movement. <FIG> illustrates a control unit <NUM> configured to control one or more of the motors <NUM>, <NUM>. An interface <NUM> provides for communicatively connecting with the motors <NUM>, <NUM>. The control unit <NUM> includes a control circuit <NUM> and a memory circuit <NUM>. The control circuit <NUM> controls the operation of the motors <NUM>, <NUM> according to program instructions stored in the memory circuit <NUM>. Within examples, the control circuit <NUM> includes one or more circuits, microcontrollers, microprocessors, hardware, or a combination thereof. Memory circuit <NUM> includes a non-transitory computer readable storage medium storing program instructions, such as a computer program product, that configures the control circuit <NUM> to implement one or more of the techniques discussed herein. Memory circuit <NUM> can include various memory devices such as, for example, read-only memory, and flash memory. In one example, memory circuit <NUM> is a separate component as illustrated in <FIG>. In another example, memory circuit <NUM> is incorporated with the control circuit <NUM>. In one example, motion profiles for the sliders <NUM> are stored in the memory circuit <NUM> to control the movement of the sliders <NUM>.

A user interface <NUM> provides for a user to control one or more aspects of one or more of the motors <NUM>, <NUM>. This can include one or more displays <NUM> for displaying information to the user. The user interface <NUM> can also include one or more input devices <NUM> such as but not limited to a keypad, touchpad, roller ball, and joystick. The one or more input devices <NUM> provide for the user to enter commands to the control circuit <NUM>.

In one example, each of the motors <NUM>, <NUM> is a stepper motor or a servo-controlled motor. The motors divide their rotational range into a series of equal steps. The control unit <NUM> can control their positions by signaling commands to move motors <NUM>, <NUM> which provides for rotational movement in defined increments to the desired rotational positions. This incremental, stepped functionality provides for the control unit <NUM> to maintain the motors <NUM>, <NUM> synchronized and the sliders <NUM> moving in accordance with the sectional shape of the nominal exterior surface <NUM> of the workpiece <NUM>.

<FIG> illustrates another example of a work platform <NUM> that synchronizes the movement of the sliders <NUM>. Motors <NUM> are attached to each of the sliders <NUM> to provide for the lateral movement to follow the workpiece <NUM>. A camshaft <NUM> is driven by a motor <NUM> and operatively connected to each of the sliders <NUM> by a link member <NUM>. In this example, the motors <NUM> are configured to provide the movement force, with the camshaft <NUM> and link members <NUM> attached to the sliders <NUM> to act as a redundant mechanical check of their synchronized movement with the workpiece <NUM>. A control unit <NUM> oversees the operation and receives signals from and controls operations of the motors <NUM>, <NUM>, <NUM> to maintain the synchronized movement.

<FIG> illustrates an example in which the cams <NUM> are driven by separate motors <NUM>. The cams <NUM> are operatively connected via link members <NUM> to the sliders <NUM> to control the lateral movement relative to the workpiece <NUM>. A control unit <NUM> controls the operation of the motors <NUM>, <NUM> to maintain the synchronized movement.

In one example of a work platform <NUM> with a camshaft <NUM>, the cams <NUM> and link members <NUM> eliminate and/or reduce the risk of the sliders <NUM> becoming misaligned with the rotation of the workpiece <NUM>. This maintained alignment ensures that the gaps formed between the sliders <NUM> and the workpiece <NUM> remain within an acceptable size and the sliders <NUM> do not contact against the workpiece <NUM>.

<FIG> illustrates an example in which motors <NUM> provide the force for moving the sliders <NUM> relative to the workpiece <NUM>. A control unit <NUM> controls the operations of the motors <NUM> and operation of motor <NUM> that rotates the workpiece <NUM>. The camshaft and link members have been removed from this example as the digital control of the motors <NUM> provides for the synchronization.

In one example, motors <NUM> that drive the sliders <NUM> are used for large work platforms <NUM> that include a large number of sliders <NUM>. The motors <NUM> can drive the sliders <NUM> and provide for more accurate movement than may be possible with a camshaft <NUM>. In one example, a work platform <NUM> that uses slider motors <NUM> is about <NUM>,<NUM> (<NUM> feet) long to extend along the length of a corresponding workpiece <NUM>.

In another example, the motor <NUM> that rotates the workpiece <NUM> also provides a driving force to move the sliders <NUM>. The motor <NUM> is mechanically linked to the sliders <NUM>, such as a chain drive, gear drive, or shaft drive. Because the motor <NUM> provides the force for both rotation of the workpiece <NUM> and movement of the sliders <NUM>, the movement of these components is synchronized.

<FIG> illustrates a method of aligning a work platform <NUM> relative to a workpiece <NUM>. The work platform <NUM> is positioned along a length of the workpiece <NUM> (block <NUM>). This can include either moving the work platform <NUM> to the workpiece <NUM>, moving the workpiece <NUM> to the work platform <NUM>, or a combination of both. This includes positioning the leading edges <NUM> of sliders <NUM> at the workpiece <NUM>. In one example, the work platform <NUM> includes a camshaft <NUM>. The work platform <NUM> is positioned with a centerline of the camshaft <NUM> being parallel with a centerline of the workpiece <NUM>. In one example, the sliders <NUM> have a centerline that is perpendicular to a centerline of the workpiece <NUM>.

The workpiece <NUM> is rotated while the work platform <NUM> is positioned at the workpiece <NUM> (block <NUM>). This provides for the one or more workers on the work platform <NUM> to continue working on the workpiece without having to move off of the work platform <NUM> to adjust the position. This provides for a higher production rate as the work area is brought to the workers in a fast, orderly process.

During the rotation, the method includes individually moving the sliders <NUM> towards and away from the workpiece <NUM> (block <NUM>). The movement of each of the sliders <NUM> is a function of the sectional shape of the workpiece <NUM> at the slider <NUM> and a rotational position of the workpiece <NUM>.

In one example, the distance between the leading edges <NUM> and the workpiece <NUM> varies during rotation of the workpiece <NUM>. In another example, the distance between the leading edges <NUM> and the workpiece <NUM> remains constant.

The work platform <NUM> can be used for a variety of different workpieces <NUM>. In one example, the work platform <NUM> is used for manufacturing composite aircraft components. Each component is constructed from overlapping composite sheets. The rotating workpiece <NUM> provides for the workers to apply the composite sheets around the entirety of the component to build the composite part.

The work platform <NUM> is applicable for positioning workers to perform work on a variety of different workpieces <NUM>. One application includes work on an aircraft sections that have relatively large sizes. The types of aircraft can vary, including various commercial aircraft, manned aircraft, unmanned aircraft, manned spacecraft, unmanned spacecraft, manned rotorcraft, unmanned rotorcraft, satellites, rockets, missiles, manned terrestrial aircraft, unmanned terrestrial aircraft, manned surface water borne aircraft, unmanned surface water borne aircraft, manned sub-surface water borne aircraft, unmanned sub-surface water borne aircraft, and combinations thereof.

By the term "about" or "substantial" and "substantially" or "approximately," with reference to amounts or measurement values, it is meant that the recited characteristic, parameter, or value need not be achieved exactly. Rather, deviations or variations, including, for example, tolerances, measurement error, measurement accuracy limitations, and other factors known to those skilled in the art, may occur in amounts that do not preclude the effect that the characteristic was intended to provide.

Claim 1:
A work platform (<NUM>) configured to be positioned in proximity to a rotating workpiece (<NUM>), the work platform (<NUM>) comprising:
a workpiece motor (<NUM>) to rotate the workpiece (<NUM>);
sliders (<NUM>) aligned along a length of the work platform (<NUM>), the sliders (<NUM>) comprising a leading edge (<NUM>), a trailing edge (<NUM>), and opposing lateral edges (<NUM>, <NUM>), the sliders (<NUM>) being arranged with the leading edges (<NUM>) positioned towards the workpiece (<NUM>);
one or more motors (<NUM>, <NUM>) that move the sliders (<NUM>) towards and away from the workpiece (<NUM>) to maintain the leading edges (<NUM>) at the workpiece (<NUM>) and with a position of the leading edges (<NUM>) being a function of the sectional shape of the workpiece (<NUM>) at the slider (<NUM>) and the rotational position of the workpiece (<NUM>); and
a control unit (<NUM>) configured to control the one or more motors (<NUM>, <NUM>) and the workpiece motor (<NUM>) to synchronize the movement of the sliders (<NUM>) with rotation of the workpiece (<NUM>).