Abstract:
A scale for measuring the weight of a subject associated with a personal mobility system. The scale includes a sheet sized to receive the subject and at least a portion of the personal mobility system, a plurality of weighing pads separate from and selectively engageable with the sheet in a pattern corresponding to either the subject or a portion of the personal mobility device, and a display device in communication with the weighing pads to display a weight either of the subject or the subject and personal mobility system.

Description:
RELATED APPLICATIONS 
       [0001]    This application is based on and claims the benefit of U.S. Provisional Patent Application No. 61/998,279 filed on Jun. 24, 2014, and U.S. Provisional Patent Application No. 61/962,350 filed on Nov. 6, 2013, the entire disclosures of which are hereby incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    The disclosure relates generally to scales arranged for use with personal mobility systems, such as wheelchairs. 
         [0003]    While most people have easy access to a scale that will accurately measure their weight, many people who use wheelchairs do not enjoy this luxury. Wheelchair users have mainly two types of options for measuring their weight and neither are easy to use or convenient. 
         [0004]    First, large platform scales exist for weighing wheelchair users. However, these scales are large, heavy, and expensive. This keeps their use primarily to large hospitals that have the money and space to invest in such resources. Even if an individual wheelchair user had the money to afford buying one, such scales do not fit well in a home. Thus, while these scales are theoretically easy to use, as the wheelchair user can simply roll on and press a button, they cannot be adopted by the wheelchair-using population as a weighing solution for home use. 
         [0005]    Second, systems are available that replace the large structure described above with a plurality of weighing pads that are designed to be aligned with each wheel of the chair and, together, weigh the user. By using separate wireless battery-powered weighing pads for each wheel, the systems are far lighter, smaller, and more portable than large platform scales. For example, such systems can be reasonably carried in a suitcase. However, these scale systems must be specially configured to match each object it is weighing, and each time it is transported and then used again, it must be assembled and configured. This poses a large obstacle for individuals with disabilities, as the process of setting up the scale is difficult and laborious, and many wheelchair users may be unable to do it without assistance, which keeps them from using such a scale independently. Even if they do have assistance, the need to set up the scale for every individual use requires extra labor. Such scales can also be extremely expensive and cost more than some large, bulky platform scales. 
         [0006]    Therefore, a need exists for a cost effective and easy to use weight measuring scale for wheelchair users. 
       BRIEF SUMMARY 
       [0007]    A scale system is disclosed that addresses the above shortcomings. The system may include a sheet of material on which at least one pad is placed. The pad&#39;s bottom surface contacts the sheet of material, and its top surface is shaped to hold a peg or wheel. Weight measurements from the pads are transferred to a readout for user display. 
         [0008]    In one aspect, a scale is provided for measuring the weight of a subject associated with a personal mobility system. The scale includes a sheet sized to receive the subject and at least a portion of the personal mobility system, a plurality of weighing pads separate from and selectively engageable with the sheet in a pattern corresponding to either the subject or a portion of the personal mobility device, and a display device in communication with the weighing pads to display a weight either of the subject or the subject and personal mobility system. 
         [0009]    In another aspect, a weighing pad is provided for use in a portable, adjustable, scale system including a plurality of the weighing pads to determine a weight of a subject associated with a personal mobility system and communicate the weight to a display device. The weighing pad includes an electronics housing, a controller arranged within the electronics housing and configured to communicate with the display device, and a load sensor in communication with the controller. A column is coupled to the electronics housing and is arranged to substantially center the subject or a portion of the subject and the personal mobility system the over the load sensor. A ramp is coupled to the column and arranged to facilitate rolling access to the column. An attachment element is arranged to selectively couple the weighing pad to the sheet. 
         [0010]    In another aspect, the invention provides a scale for measuring the weight of a subject sitting in a four-wheel wheelchair. The scale includes a sheet of flexible material arranged to lay flat on a floor surface and be manipulated into a storage arrangement, and four weighing pads separate from and selectively engageable with the sheet in a pattern corresponding to the four wheels of the wheelchair. Each of the weighing pads is independent of the other weighing pads and includes an electronics housing, a controller arranged within the electronics housing, a load sensor in communication with the controller, a column coupled to the electronics housing, arranged above the load sensor, and configured to substantially center one of the wheels over the load sensor, a ramp coupled to the column and arranged to facilitate rolling access to the column, and an attachment element arranged to releasably couple the weighing pad to the sheet. The scale further includes a display device that is in communication with the controllers of the weighing pads to display a weight of the subject and the wheelchair. 
         [0011]    The foregoing and other aspects and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention, however, and reference is made therefore to the claims and herein for interpreting the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]    The disclosure will be better understood and features, aspects and advantages other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such detailed description makes reference to the following drawings. 
           [0013]      FIG. 1  is a photo of a personal mobility system, in the form of a wheelchair, and user weighing himself on a scale including four pads according to the present disclosure. 
           [0014]      FIG. 2  is a pictorial view of the scale of  FIG. 1 . 
           [0015]      FIG. 3  is a pictorial view of one of the pads of the scale of  FIG. 1 . 
           [0016]      FIG. 4  is a side view of the pad of  FIG. 3 . 
           [0017]      FIG. 5  is a pictorial view of an adjustable width pad according to another aspect of the disclosure. 
           [0018]      FIG. 6  is a top view of a pattern used to arrange the pads on the scale of  FIG. 1 . 
           [0019]      FIG. 7  is a pictorial view of another pad according to the disclosure. 
           [0020]      FIG. 8  is a pictorial view of the pad of  FIG. 7  with spacers installed. 
           [0021]      FIG. 9  is a front view of a display device according to one embodiment of the disclosure. 
           [0022]      FIG. 10  is an operational flowchart illustrating operation of the scale of  FIG. 1 . 
           [0023]      FIG. 11  is a pictorial view of a placeholder that may be used with the scale of  FIG. 1  for conveniently attaching the pads. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
         [0025]    The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention. 
         [0026]      FIG. 1  shows a subject in the form of a user  10  sitting in a personal mobility system, illustrated as a wheelchair  11 , that acts as the platform on top of a portable, configurable low-profile scale  12 , looking at a display device  13  to read his weight. That is, personal mobility systems may include a variety of systems including crutches, walkers, wheelchairs, scooters, and the like. The user  10  might be a person with limited mobility, either walking, using crutches or a walker, or using a wheelchair. In other words, the wheelchair  11  may be replaced with another personal mobility system (e.g., crutches, a walker, a scooter, and so on) and the scale  12  configured to accurately measure the weight of the subject. To this end, reference to a wheelchair is for illustrative purposes only and can be substituted with other personal mobility systems. In other arrangements, the subject may be an animal or an object. The user  10  may use the scale  12  independently or with assistance. 
         [0027]    While typical scales have some kind of platform built in, the inventive scale  12  makes use of the personal mobility system or assistance device, such as wheelchair  11 , to provide the platform. By removing the often bulky and heavy platform of typical scales, the scale  12  is made more portable and less expensive while still being easy to use by users  10  with a readily available platform (e.g., wheelchair  11 ). The platform could be anything that supports itself with legs or wheels such that some or all of the legs or wheels fit onto a weighing pad  15 . Possible platforms include a wheelchair  11  with wheels  14 , a large sheet of sturdy material with pegs (i.e., a portable platform), a chair, a bed, a table, a walker with or without a seat, or a vehicle. Because the scale  12  is designed to be easily configured by the user  10 , the same scale  12  can be easily used with a variety of platforms by rearrangement of the pads  15 . 
         [0028]    The display device  13  can be wireless or wired and it can be a device that comes with the scale  12 , a phone, a computer, or any other device with the capability to receive and display information. A display device  13  which is wireless is preferred because long wires can tangle or interfere with the use of the scale  12 . The display device  13  can have a visual display or it can have an audio output. Having both a visual and an audio output provides the advantage of being accessible to those with hearing impairments and those with visual impairments. Having the output on a display device  13  which is wireless is particularly advantageous for wheelchair users or others with a physical disability as it allows them to use the scale  12  without needing to look down at the scale  12 , which may be difficult to do around a wheelchair  11 , or may be difficult if use of the neck and upper body is impaired. A display device  13  which is wireless also allows the user  10  to use the scale  12  while moving their wheelchair  11  using their hands to push the wheels  14  or an electric system controller such as a joystick by not requiring the use of the hands to transport it, as it can be placed in the lap or mounted onto the wheelchair  11 . 
         [0029]    Turning to  FIG. 2 , the illustrated scale  12  includes four weighing pads  15  on a sheet of material  20 . The scale  12  may have any number of pads  15 , and these pads  15  may be placed in any configuration on the sheet  20 . The configuration will be chosen to match the desired platform. For example, the scale  12  can be configured for a typical manual wheelchair  11  with four pads  15  placed on the sheet  20  such that one pad  15  is directly under each wheel  14  during use. 
         [0030]    As shown in  FIG. 3 , each pad  15  includes a plastic housing  30  that encases the inner parts of the pad  15  and protects them from moisture, debris, and force. The housing  30  can be made of any sufficiently rigid material, such as ABS, PVC, or PP plastics, such that it does not break or significantly bend under the forces applied by the user  10  and platform. 
         [0031]    The housing includes a column  31  that transfers the load of the user  10  from the platform to the inner parts of the pad  15  where that load is measured. The column  31  may be shaped to fit the wheels  14 , pegs, or legs of the wheelchair  11  or platform to help center the load over the column  31 , which can increase the accuracy of many weighing methods, especially pneumatic weighing methods. The column  31  design depicted is one example of a design that will hold a wheel  14  in place over the column  31  without allowing it to roll while also centering the wheel  14  over the column  31 . This makes it easier for the user  10  to get the wheels  14  of the wheelchair  11  in the right place on the scale  12 , and it increases the accuracy by centering the load. The column  31  can be made out of any rigid material that can hold the load while remaining intact, including wood, metal, or plastic. 
         [0032]    The housing further includes, ramps  32  that assist the user  10  in rolling or otherwise moving the platform onto the column  31  of the pad  15 . The ramps  32  can be a part of the housing  30 , or they could be a separate part made of a similarly rigid material that is able to withstand the weight of the subject being weighed (e.g., the user  10 ). The ramps  32  could be permanently removable, removable and easily reattached to the housing  30 , or entirely absent if unnecessary, for example if being used with a platform that does not roll, like a chair or static bed, or if the pad is low enough that the ramps  32  are not necessary. Having removable or absent ramps  32  provides the advantage of lowering the weight and bulk of the pad  15  when used in situations where the ramps  32  are not necessary. 
         [0033]    The housing  30  can be specifically designed to aid in the use of the scale  12  with different platforms. For example, it may have guiding ridges  33  which can help direct the wheels  14  of the wheelchair  11  properly over the column  31 . 
         [0034]    An electronics housing  34  can be contained under any part of the pad  15 , such as the ramp  32 , guide ridges  33 , or the column  31 , or it could be entirely separate. 
         [0035]    The housing  30  also includes an attachment element  45  for attaching to the sheet  20 , as shown in  FIG. 4 . The attachment element  45  can take the form of holes into which a push rivet or adhesive strip is anchored, magnets, hook-and-loop fasteners, places where pegs stick out, or anything else to help attach the pad  15  to the sheet of material  20 . 
         [0036]    The pads  15  may also provide feedback to the user  10  to help the user  10  make sure the platform is properly placed onto the pads  15 . This feedback could be tactile, such as a going over a bump to get onto the column  31 , or it could be an auditory or visual feedback provided by the pad  15 , the display device  13 , or both. This feedback is particularly advantageous to wheelchair users  10  using the scale  12  who may not be able to look at the wheels  14  of the wheelchair  11  to check if they are properly placed on the pads  15 . 
         [0037]    The pads  15  may also have features that make them easy to move around during the configuration process. This could include a strap or loop of fabric to make the pads  15  easier to grab for people with physical disabilities. It could include a clip so that wheelchair users  10  could clip the pads onto their wheels  14  at the top of the wheels  14 , then roll the wheels  14  such that the pads  15  are under the wheels  14 . 
         [0038]    Turning to  FIG. 4 , positioned within the illustrated pad  15  are a rigid plate  40 , a flexible pressure vessel  41 , a pressure sensor  42 , and a printed circuit board  43 . The illustrated pressure sensor  42  and printed circuit board  43  are arranged within the electronics housing  34  and sealed from outside elements by a seal  44 . 
         [0039]    The rigid plate  40  is part of the column  31  and aids in transferring the load to the load sensor. The accuracy of the pressure-based pads  15  is dependent on the rigid plate  40  having constant area contacting the flexible pressure vessel  41 . The rigid plate  40  must be made out of a material stiff enough to prevent bending, because bending would change the contact area and lead to inaccuracy of the scale measurement. The rigid plate  40  rests on top of the flexible pressure vessel  41 , which is attached to the pressure sensor  42  such that the fluid or air in the system does not leak. 
         [0040]    The pads  15  may use any mechanism for weighing, including strain gauges, a pneumatic system with non-compressible or compressible fluid, or capacitive plates. The pads  15  that the user rolls onto are advantageously thin (less than 0.75 inch thick) and make it easier for the user  10  to roll, place, or otherwise move the wheelchair  11  or other platform onto the scale  12 . Keeping the pads  15  smaller also helps reduce the overall bulk and weight of the scale  12 , and makes the scale  12  easier to manipulate, which makes storing or moving the scale  12  easier for the user  10 . The ease of storage and movement of the scale  12  is especially important for users with physical disabilities, who may have more difficulty manipulating and transporting them than the general population. The size can be kept to a minimum by keeping the pads  15  thin and by reducing the electrical components in each pad  15  by moving functions like conversion, averaging, filtering, or display to the display device  13 , rather than having these functions done by the sheet of flexible material  20  or the pads  15 . 
         [0041]    In these images the pads  15  are positioned on and attached to a sheet of flexible material  20  to hold them in place, although the pads  15  can also be used without the sheet  20  or can be used on the sheet but without being attached to the sheet  20 . The pads  15  can be attached to the sheet  20  through any method of attachment (e.g., attachment element  45 ), including plastic rivets, hook-and-loop fasteners, tape, glue, friction, magnets, or pegs, so long as they will not be accidentally shifted or moved during use and will instead maintain the chosen configuration. Attaching the pads  15  to the flexible sheet  20  allows the whole scale  12  to be manipulated for storage without changing the configuration. Thus if the scale  12  is being used for only one platform, it can be easily stored or transported without the need to reconfigure the scale  12  each time, saving time and effort and increasing independence for the user  10 . This is especially advantageous to users  10  with a physical disability that may make configuring the scale  12  especially difficult. 
         [0042]    This attachment process could be made easier through the use of a template  60  as shown in  FIG. 6 , which can be shaped to match the layout of a pad and can thus more easily indicate where holes must be made or hook-and-loop fasteners attached in order to have a pad  15  in a certain location on the sheet  20 . The attachment process could also be made easier through the use of a placeholder  110  (See  FIG. 11 ), a 3-dimensional object that could be placed on the mat such that the pad  15  clips into it or otherwise gets attached. This would allow the configuration to be maintained even if a pad  15  needs to be removed for any reason, for example to replace a battery or to share pads  15  among multiple users  10 . 
         [0043]    The same scale  12  can be used with multiple different users  10  or platforms possibly by using multiple sheets  20  with different marked configurations, different configurations of attached placeholders  110 , or by reconfiguring the pads  15  on the same sheet  20 . This could be useful, for example, for a visiting physician who wishes to use the scale  12  with multiple patients who use different wheelchairs. Configurations could be marked on the sheet  20  using masking tape, markers, or any other method. Methods that allow multiple configurations to be marked at once on the same sheet  20  may be preferred so that the sheet  20  can be shared, and methods that are removable may be preferred for aesthetic reasons. 
         [0044]    The pads  15  could contain the necessary parts to measure, compute, and wirelessly transmit weight data, or they could be connected to other parts of the scale  12 , such as a central electronics box, that perform some or all of these functions. Information could be transmitted through wires, which could be free or embedded in the mat, or information could be transmitted wirelessly via any method including Bluetooth, WiFi, or cellular telephone signals. Transmitting information via Bluetooth has the advantages of working well at close distances, interfacing well with modern smartphones, being low cost, and using little power. Pads  15  could be powered by any energy source, including an external power source like a wall outlet, or by internal batteries, which could be rechargeable or non-rechargeable. Self-contained batteries or wireless power transfer provide the advantage of reducing external wires or connections that can tangle or interfere with the use of the scale  12 . The pads  15  may contain their own calibration information used to calculate weight from a measurement, or that information may be stored externally, for example by the display device  13  or on the internet such that the display device  13  can access it. 
         [0045]    The sheet  20  can be made of any durable and/or flexible material like rubber, fabric, vinyl, leather, elastomer foams, wood (e.g., a hinged plywood sheet), or bamboo mats. A sheet made from a flexible and durable material is preferred because the flexibility allows the sheet  20  to be rolled up or folded for storage, possibly with the pads  15  still attached, and the durability allows it to be rolled up or folded, moved, and used many times without deteriorating. A rubber material similar to that used for yoga mats is advantageous for the sheet  20  because it provides good grip between the sheet  20  and the floor as well as between the sheet  20  and the pads  15 . This will help keep the sheet  20  from bunching up when wheels are rolled over it and will help keep the pads  15  from moving during use. A less squishy sheet  20 , such as a tough rubber or a thin fabric, can improve accuracy by keeping the pads  15  from tilting if a load is applied off-center and the pad technology needs weight to be focused on the center of the pad. The sheet  20  may also have images or pictures on it, such as a grid, indications for where to place the pads  15 , or logos. These images may assist in the configuration of the scale  12 . The sheet  20  may also have holes, additional parts, or other physical modifications to assist with configuration, rolling, moving, or storage. Some examples of potential physical modifications to the sheet  20  include a hook-and-loop fastener strap to keep it rolled up, plastic pegs in a set configuration in the mat to attach to pads  15 , or a small loop or handle to assist with being picked up or moved. The sheet  20  should be large enough to encompass the footprint of the user&#39;s platform. In the case of most manual wheelchairs 36″×36″ is enough, but these dimensions may need to be larger to accommodate electric wheelchairs or electric scooters. 
         [0046]    Another pad  15 ′ is shown in  FIG. 5 . Two weight measurement mechanisms, in this case strain gauge devices  50 , form the guiding ridges  33 ′ which guide a platform onto the column  31 ′. The column  31 ′, instead of being directly on top of the weighing mechanism, is attached to the strain gauge devices  50  on each side, and then descends to form a basket-like shape. This way the part of the column  31 ′ on which the platform is placed is kept as thin as possible, keeping it easy to roll or place a platform. This design could be used with weighing methods other than strain gauges. For instance, it could have a pneumatic weighing device on either side instead. 
         [0047]    Turning to  FIG. 6 , the template  60  that could be used to mark or modify a sheet  20  to prepare it for attaching pads  15 . This template  60  could have holes  61  corresponding to the attachment element  45  on a pad  15 . These holes  61  can then help direct the user  10  configuring the scale  12  where to mark or make holes or attach parts to help attach the pads  15 . Instead of holes the points could instead be tools for piercing the sheet  20  such that holes are made in the proper place for attachment. The template  60  could also have a window  62  that corresponds to where the column  31  or another relevant part of the pad will be to help the person configuring the scale  12  place the template  60  in the correct place. 
         [0048]    In  FIGS. 7 and 8  there is shown a configurable pad design  70 . Since pads  15  are more accurate for some weighing technologies when the load is properly centered over the pad  15 , it is advantageous to have a pad  15  that aids the user  10  in centering the leg or wheel  14  of the platform on the pad  15 . In addition to the pad components shown in  FIGS. 3 and 4 , the configurable pad  70  has slots  71  for spacers  80 . The spacers  80  are added to reduce the available width to match the width of the wheel  14  or peg of the platform. The spacers  80  can be made out of any solid material, such as wood, plastic, metal, an inflatable pressure vessel, compressible foam, or rubber. If the spacers  80  are rigid they can be made hollow to reduce weight and material use, but it is not necessary for their operation. Other mechanical designs to achieve the same result can also be used, including spacers that slide and are locked into place by friction, pegs, or some other attachment method. 
         [0049]    In  FIG. 9  there is shown an example display device  13 . The display device  13  may include a screen  90  which displays the weight visually, a speaker  91  for an audio output if desired by the user  10 , and at least one button  92  which the user uses to query weight. The display device  13  can also include a loop or handle  93  to help the user  10  to pick up or hold on to the display device  13 . The display device  13  can also include additional buttons, switches, or menus to help the user  10  change options or settings, such as taking a tare weight, changing the units, or creating and managing a profile that stores a specific tare weight or other information for a specific user or group of users. The display device  13  could also have a mounting mechanism  94  to attach it to a wall or part of the platform  11 , such as the arms or back of a wheelchair. A mounting mechanism  94  could be advantageous for people who may not prefer to or may not be able to hold the display device  13 . 
         [0050]    Much of the computational work of the scale  12  can be allocated to the display device  13 , thereby saving cost and bulk in the pads  15 , which then may not require electronic components capable of doing complex computation. This computational work can include filtering the weight data, averaging the weight data, storing weight data, displaying aggregate weight data (e.g. as a graph of weight over time), storing user information as a profile, determining the correct user profile, alerting the user  10  if a particular event happens, a pad  15  is damaged or needs the battery replaced, or a goal is reached, or communicating with the internet or other applications on the display device  13 . 
         [0051]    The ability to have multiple profiles may be especially useful for doctors or nurses that may use the same scale  12  with multiple users  10 , or for users  10  who may be sharing the scale  12 . Being able to determine the correct profile based on matching weight or based on an ID associated with a particular sheet  20  reduces the burden on the user  10 . 
         [0052]    The flowchart in  FIG. 10  describes the process of reading weight measurements from each pad  15  and sending a weight value to the display device  13 . In step  105 , the measured weights from each pad  15  (calculated in steps  100 - 104 ) are added together. In the chart, there are five pads  15  that calculate weight, and all five are added together. For any number of pads  15 , all of the weights would be added together to calculate a total weight. 
         [0053]    In step  106 , the scale  12  subtracts the previously measured weight of the platform being used (e.g., the wheel chair  11 ), the weight of which is known as the tare weight. This step may or may not be used. This could be a weight that is known and is an input from the user  10 , or it could be a weight that is measured and then stored by the scale  12 . If this function is not needed, the tare weight may be the weight reading when there is no load on the scale  12 . The resulting measurement is the weight of the subject (e.g., user  10 , an animal, or another object) being weighed, which may be transmitted (at step  107 ) wirelessly or through wires to a phone, computer, or other remote device (e.g., the display device  13 ). The phone, computer, or other remote device may then transfer that information to the internet, to display on websites or applications such as www.facebook.com or a website or application used to monitor weight or aggregate health data over time, or to another person, such as the user&#39;s doctor. 
         [0054]    In  FIG. 11  there is shown an example placeholder design. The placeholder  110  is composed of walls  111 , which securely hold the pad  15  in the placeholder without letting it slide or move. The placeholder  110  is attached to the sheet of flexible material  20  through a secure and semi-permanent attachment  112 , which could be a rivet, magnets, hook-and-loop fasteners, tape, a bolt, or any other attachment method. The pad  15  can then be secured in the placeholder  111  through a non-permanent attachment  113 , which could be magnets, hook-and-loop fasteners, a click fitting, or any other repeatable non-permanent attachment. This allows a user  10  to easily and conveniently share a set of weighing pads  15  with multiple different configurations on different sheets  20 . Placeholders  110  with a more permanent attachment to the pad  15  may be used for scales that are only used by a single user. 
         [0055]    It will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein.