in the following detailed description , certain specific terminology will be employed for the sake of clarity and a particular embodiment described in accordance with the requirements of 35 usc 112 , but it is to be understood that the same is not intended to be limiting and should not be so construed inasmuch as the invention is capable of taking many forms and variations within the scope of the appended claims . referring to fig1 , the apparatus 10 according to a first embodiment of the invention includes a contour sensor arrangement supported by a support member , here shown as comprised of an elongated sensor bar 16 which mounts a series of height or thickness sensors 38 extending along the length of the sensor bar 16 . sensor bar support posts 20 , 22 are provided at each end of the manually movable sensor bar 16 , a handle 18 provided at one end to enable convenient manual movement by a user . the posts 20 , 22 locate the sensor bar 16 at a predetermined height above a support surface defined by a table 12 . a motion detector arrangement is provided to generate signals corresponding to the extent and direction of motion of the sensor bar 16 , during manual stroking of the sensor bar 16 over the surface of the table 12 and along an item 14 to be portioned resting on the table 12 . in this embodiment , the motion detector arrangement includes motion detectors 40 , 42 located at the bottom end of each support post 20 , 22 , respectively . as described in the cross referenced co - pending application , a contour sensing arrangement comprised of a linear series of height sensors 38 installed extending along the length of the sensor bar 16 which produce signals corresponding to the height of the upper surface of the item 14 above the support surface defined by the table 12 at points along the cross section of the item 14 aligned with the sensor bar 16 . alternatively , sensors 38 may sense the thickness of the item 14 at points along the section of the item lying below the sensor bar 16 , as described in the co - pending cross - referenced application . this contour sensor arrangement generates signals corresponding to the cross sectional contour of the item 14 at each section lying below and aligned with the sensor bar 16 at successive positions thereof along the item 14 . the height or thickness sensors 38 can be of various types , as described in detail in the cross - referenced co - pending application , such as optical or sonic sensors emitting and receiving light or sound waves respectively and receiving reflections thereof from the item 14 , or penetrating the item 14 and reflecting from the surface of the table 12 . the motion detector and sensor arrangement signals are transmitted to a signal processor 24 which may be a programmable microprocessor contained in a casing 26 as shown in fig2 , which computes the total volume of the selected segment of the item 14 from the motion detector and contour sensor arrangement signals . this calculated volume is converted into a corresponding numeric value , usually the weight or a price based on the weight of a selected segment of the item 14 . this numeric value is displayed substantially contemporaneously in an upright display 30 which may be mounted to the casing 26 as shown in fig1 and 2 . the motion detectors 40 , 42 each generate electronic signals corresponding to the direction and extent of horizontal motion of the bottom end of each support post 20 , 22 respectively as the sensor bar 16 is moved in either direction along the item 14 from a starting or reference position over any selected section of an item 14 to be portioned to reach a position over another selected section of said item 14 . as the sensor bar 16 is moved along the item 14 on the table surface 12 , the bottom end of each support post 20 , 22 is intended to be kept in constant contact with the surface of the table 12 . according to the present invention , the signals generated by each of the motion detectors 40 , 42 are processed to determine the displacement and direction of displacement of the bottom of each post 20 , 22 respectively . the motion detectors 40 , 42 are each preferably comprised of accelerometers included therein , and preferably of accelerometers of a type known as “ mems ” ( micro electro - mechanical systems ) accelerometers . mems accelerometers may be based on various designs and sensing methods some of which are described in an article titled “ design of padless mouse system with mems accelerometers and analog read - out circuitry ” ( by seungbae lee , gi - joon nam , junseok chae , and hanseup kim , department of eecs , university of michigan , usa ). this article discusses some mems accelerometer sensing technologies including piezoelectric , tunneling , and capacitive . other technologies include ( but are not limited to ) strain gauge sensing . this article is hereby incorporated by reference into this application in its entirety . mems accelerometer devices are well known and are also described in u . s . published application 2004 / 0211258 , and u . s . pat . nos . 5 , 392 , 650 ; 5 , 006 , 487 ; 4 , 945 , 765 ; 4 , 699 , 006 ; and 4 , 512 , 192 , also incorporated herein by reference . as described in the referenced article , the use of two such mems accelerometers mounted orthogonally to each other enables the determination of the positions in a plane of a member that is moved over a 2 - dimensional flat surface . also , as described , the use of three orthogonally arranged mems accelerometers enables the determination of the positions in space of a member that is moved about in that space . thus , in a three dimensional implementation , if a member that is moved over a flat surface is lifted off the flat surface or tilted , the three axis arrangement of mems accelerometers will enable detection of that occurrence . each of the motion detectors 40 , 42 associated with the respective sensor bar support posts 20 , 22 may consist of an orthogonal arrangement of two mems accelerometers that enables the sensing of the accelerations of the respective sensor bar support posts 20 , 22 about two orthogonal axes as the sensor bar 16 traverses the table 12 with the support posts 20 , 22 staying in constant contact with the surface of the table 12 . the corresponding generated signals are communicated to and processed by a signal processor 24 to derive signals corresponding to displacements of the end of each sensor bar support post 20 , 22 as the sensor bar 16 is moved along the item 14 . an orthogonally arranged cluster of three mems accelerometers may also be employed as motion detectors 40 , 42 that are associated with the respective sensor bar support posts 20 , 22 . the use of three clustered mems accelerometers enables the detection of three axes of acceleration of the lower free end of each of the respective sensor bar support posts 20 , 22 as the sensor bar 16 is moved along and above the item 14 . the detector signals are communicated to and processed by the signal processor 24 to determine the displacements of the end of each sensor bar support post 20 , 22 as the sensor bar 16 is moved along the item 14 on the table surface 12 . the resultant ability to detect vertical axis accelerations allows detection of lift off of one or both of the sensor bar support posts 20 , 22 from the surface of the table 12 such as when an operator inadvertently lifts one or both of the support posts off the table 12 when passing the sensor bar 16 over the item 14 . an audible alarm 28 ( fig2 ) in the display case 26 may be sounded when this occurs , thus alerting the operator of the need to start over in scanning the item 14 in order to ensure accurate results . the use of a single axis mems accelerometer aligned to sense vertical movement of the sensor bar 16 may also accomplish this same purpose . the sensor bar 16 and support posts 20 , 22 should be consistently held in a substantially vertical orientation . the determination of the support post motion in three axes may be utilized to detect tilting of the sensor bar 16 . for this determination , alternative higher locations of the motion detectors 40 a , 42 a ( as exemplified in fig1 a ) or 40 b , 42 b ( as exemplified in fig1 b ), are preferred , as an out - of - plumb sensor bar 16 position would usually cause a greater sensor bar vertical axis positional change at the top of the support posts 20 , 22 or the sensor bar 16 itself than at the bottom thereof . thus slight tilting will be more easily detectable . an out - of - plumb alarm or indicator 34 ( fig2 ) in the case 26 may be triggered responsive to an excessive tilted orientation of the sensor bar 16 as detected by the motion detectors , 40 a , 42 a , 40 b , 42 b . this arrangement also supplements or could eliminate the need for a separate spirit level 36 ( fig2 ) or other tilt indicator . the orientation of the sensor bar 16 may also be used to mathematically compensate when calculating the weight or price of a selected segment of the item 14 when the sensor bar 16 is tilted , instead of merely activating a tilt alarm 34 . thus , the preferred mems based accelerometers used in the motion detectors 40 a , 42 a or 40 b , 42 b are those that are comprised of a three axis cluster of mems accelerometers that enables the determination of the orientation of the sensor bar 16 as the sensor bar 16 is traversed over the table surface 12 , enables a determination if one or both of the sensor bar support posts 20 , 22 has lifted off of the table surface 12 , and enables the determination of the extent and direction of motion of each of the support posts 20 , 22 . the unlimited variety of locations for the mems accelerometer based motion detectors enables these detectors to be placed in the most secure / stable locations that are less subject to vibrational , physical , or other stresses , thus avoiding possible false readings or displacement detector damage . such stresses would often occur at the lower ends of sensor bar support posts 20 , 22 as this area is in constant contact with the surface of the table 12 as the sensor bar 16 traverses the surface of the table 12 . this versatility in motion detector placement enables a more flexible sensor bar design in order to meet the demands of various applications , manufacturing requirements , or aesthetic requirements . the use of multiple axis clustered accelerometer versions of mems motion detectors 40 , 42 enables detection of lift up of one or both of the support posts 20 , 22 off the table surface 12 by detecting vertical motion thereof . this offers clear advantages over the displacement detectors described in the above cross referenced parent utility application . although optical based displacement detectors described therein can detect a loss of reflected light from the surface of the table 12 due to the lifting of displacement support posts 20 , 22 off the surface of the table 12 , such loss of reflected light can also result from other conditions such as a dirty or dull finished surface of the table 12 . although electromagnetic based displacement detectors also described in the parent application may also detect when sensor bar support posts are lifted off of the surface of the table 12 by sensing the absence of magnetic fields , the use of those displacement detectors requires a specialized digitizer tablet type table surface instead of an off - the - shelf conventional cutting board as can be used with the mems accelerometer motion detectors 40 , 42 . similarly , although previously described firm - pointed stylus pressure sensitive based displacement detectors may detect when support posts 20 , 22 are lifted off the surface of the table 12 by sensing the lack of pressure from the pointed stylus , the use of such displacement detectors requires a specialized pressure sensitive tablet based table surface whereas an off - the - shelf conventional cutting board can be used with the mems accelerometer based motion detectors 40 , 42 . alternatively , separate mems accelerometer based motion detectors that each contain only a single axis mems accelerometer may be placed elsewhere on or in the sensor bar 16 , or carried on or in other components on the sensor bar 16 to determine if the sensor bar 16 has moved upwards ( indicating one or both of the sensor bar support posts 20 , 22 has moved upwards off of the table surface 12 ). mems accelerometer based motion detectors may be utilized in all sensor bar configurations such as those described in this application as well as the cross referenced parent application in place of displacement detectors based on other technologies such as optical , optical - mechanical , electromagnetic , pressure - sensitive tactile , etc . for example , the moiré fringe optical displacement detector described in the parent application may be replaced with one or both of the mems accelerometer based motion detectors 44 a or 44 b as illustrated in fig3 . that is , either one or both of motion detectors 44 a or 44 b may be mounted to respective sides of either upright 46 or 48 as shown in fig3 . alternatively , a single mems accelerometer based motion detector 44 a , 44 b may be mounted to only one of the uprights 46 , 48 or to the connected portion of the sensor bar 16 a to sense single axis motion only along the direction of constrained movement across the table 12 a since the sensor bar 16 a is itself constrained to move along a single axis over the table 12 a . both detectors 44 a , 44 b may be used for the sake of redundancy or to detect skewing caused by bearing wear , etc . the mems based accelerometers 44 a , 44 b are each comprised of a single axis mems accelerometer as only the determination of the extent and direction of linear motion is required . the mems accelerometer based motion detectors used to replace other displacement detectors in the cross referenced co - pending application may incorporate either a combination of two orthogonally oriented mems based accelerometers to sense movements along two orthogonal axes in the plane of the item support surface or a cluster of three orthogonally oriented mems based accelerometers to detect motion along three orthogonal axes in the plane of the item support surface and the space above the support surface . each of the mems accelerometer based motion detectors 40 , 42 , 40 a , 42 a , 40 b , 42 b , 44 a , 44 b are preferably encased in a sealed housing isolated from the environment whereby they are not subject to damage by debris , water , dirt , oils , cleaning products , or other contaminants . furthermore , this sealed environment isolates the mems accelerometer based displacement detector from physical damage ( e . g ., chipping , cracking , scratching , or frictional induced damage ) caused by contact with either the table surface 12 or other materials , surfaces , equipment , or utensils and thus can better withstand operator abuse or neglect such as a standard knife or other kitchen utensil may encounter . mems accelerometer based motion detectors 40 , 42 , 40 a , 42 a , 40 b , 42 b , 44 a , 44 b also do not have any macro moveable components that are subject to macro frictional wear . furthermore , due to the sealed housings and maintenance free aspect of the mems accelerometer based motion detector , the disassembly , removal , or special handling of the motion detectors is not required prior to or during cleaning of the sensor bar 16 . as mems accelerometer based motion detectors 40 , 42 , 44 a , 44 b do not interact with the surface of the table 12 , their operation is independent of the type of table employed as well as the condition of the table surface 12 . hence , acceptable tables may be constructed out of virtually any type of material such as wood , plastic , marble , etc . acceptable surfaces for the table 12 may also be smooth , rough , reflective , non - reflective , greasy , oily , wet , slippery , dusty , etc . the lower ends of the sensor bar support posts 20 , 22 easily maintain constant contact with virtually any table surfaces 12 as they are able to glide on smooth , rough , reflective , non - reflective , greasy , oily , wet , slippery , or dusty surfaces as the sensor bar 16 ( or other sensor arrangement support ) traverses the table surface 12 . these just described surface conditions are common in many situations where for example portioning of fish filets is carried out . as is fully described in the apparatus described in the cross referenced co - pending application , as the sensor bar 16 ( or other sensor arrangement support implementations ) traverses the table surface 12 , the displacement of the sensor bar 16 is continually determined from the signals generated by the motion detectors 40 , 42 employed . such determinations of displacements are required in order to carry out calculations to determine the volume of a segment and thus the weight or price of any selected segment of the item 14 defined between any two selected sections of the item lying below the sensor bar 16 in two positions thereof as described in the cross referenced co - pending u . s . patent application . as described in the cross referenced co - pending patent application , a linear displacement sensor based on a photoelectric reflection array may be used to measure the vertical displacement of plungers 50 shown in fig4 which are used as a sensor arrangement for determining the cross sectional contour of successive sections of the item 14 , or for marking , scoring , or cutting of the item 14 . a linear displacement sensor may also be used to determine when a plunger 50 rests on the top surface of the item 14 , or to determine when a plunger 50 has been fully withdrawn into its retracted position inside of the sensor bar 16 b . each such linear displacement sensor based on photoelectric reflection array technology may be replaced with a mems accelerometer based linear motion detector that utilizes a single axis mems accelerometer , to determine vertical displacements . each mems accelerometer based linear motion sensor detector 52 is shown mounted within the lower end of plunger 50 in fig4 and 6 . another acceptable location of a mems accelerometer based linear motion sensor 52 a ( fig5 ) is between the plunger stem 47 and main plunger body 54 . only one of the single axis motion sensors 52 , 52 a would normally be mounted to each plunger 50 . the use of the mems type accelerometers in detectors 52 , 52 a enables the sensing of the vertical z axis acceleration of the plunger 50 as the plunger 50 moves up and down ( and possibly stops ) through the cavity 58 formed by the solenoid coil windings 56 . as illustrated in fig5 and 6 , by utilizing mems accelerometer based linear motion detectors , 52 , 52 a , the optical components associated therewith described in the cross referenced co - pending application is eliminated , and the plungers 50 may completely occupy the cavity 58 formed by the solenoid coil windings 56 . mems accelerometer based linear motion detectors 52 , 52 a also do not require that the springs 60 have a matte finish . the signals corresponding to the acceleration of the plungers 50 generated by the associated mems accelerometer 52 , 52 a are transmitted to the signal processor 24 ( fig2 ) to compute the relative vertical or z axis displacement of each plunger 50 as the plunger 50 moves up and down ( or stops ) within the above described cavity 58 . the signal processor 24 contained in case 26 ( fig2 ) processes those signals to calculate the cross sectional contour of the section of the item 14 under the sensor bar 16 b , or to determine when a plunger 50 has settled ( without movement ) onto the top surface of the item 14 , or to determine when a plunger 50 has settled ( without movement ) into its fully retracted position inside of the sensor bar 16 b . as the mems accelerometer based linear motion detectors 52 , 52 a are each contained within or otherwise associated with the plunger 50 , the plunger 50 is a one - piece unit which is contained within the cavity 58 formed by solenoid windings 56 . this one - piece construction simplifies the construction of the overall plunger assembly . since the mems accelerometer detector 52 , 52 a of this one - piece unit acts independently of surrounding assemblies or mechanisms , the possibility of misalignment during installation and use is minimal . furthermore , as exemplified by the location of the detectors 52 or 52 a in fig5 and 6 , the mems accelerometer motion detectors 52 , 52 a may be placed in various locations . this provides for flexibility of design and manufacturing and also enables the mems accelerometer motion detectors 52 to be placed in areas less subject to physical and vibrational stresses as undergone at locations near the bottom end of plungers 50 . each of the mems accelerator based linear motion detectors 52 , 52 a are preferably encased in a sealed housing isolated from the environment whereby they are not subject to damage by debris , water , dirt , oils , cleaning products , or the other contaminants . when the position of a sensor bar 16 is used to visually indicate to an observer the sections of the item 14 which define an item segment of interest , it may be desirable to make it easier to see the bounds of the segment of the item as it corresponds to the numeric display . since the sensor bar 16 may have appreciable thickness and is spaced above the item 14 , the exact item section lying directly beneath the sensor arrangement associated with the sensor bar 16 may not be easily ascertained by an onlooker . similarly , the viewing angle of an observer such as a customer or operator may affect his or her ability to determine the exact location of that section . when plungers 50 are used , this is not a problem , but with non - contact sensors it may be desirable to provide a clearer indication to the observer of the exact item segment corresponding to the display . a more accurate discernment of the segment bounds may be enabled by projecting an elongated pattern , i . e ., a narrow band of visible light onto the item 14 extending across the section which contour is being determined from the signals generated by the sensors 38 . this is shown in fig7 where a selected start reference section of the item 14 is temporarily indicated by a curved wire marker element 63 positioned on the surface of the table 12 by the weight of attached blocks 61 , or by magnetic attraction of magnetized blocks 61 to a magnetic support surface 12 . the marker element 63 , is placed in alignment with a narrow light band projected from the sensor bar 16 onto item 14 at a start or reference position of the sensor bar 16 . the sensor bar 16 is then shifted to a second position where a narrow visible light band 62 is projected to impinge onto the item 14 extending across a section spaced from the start position . the light band is projected from the underside of a sensor bar 16 c , 16 d ( fig8 , 9 ). the weight or cost of a segment of the item 14 defined between the start section below wire marker element 63 and the offset section at the light band 62 in the second position of the sensor bar 16 c , 16 d will be numerically shown by display 30 . this provides a more readily seen visual indication of the bounds of the particular segment of the item 14 corresponding to the displayed weight or cost .” fig8 shows one arrangement for producing the projected narrow visible light band 62 . a series of lamps , visible light emitting diodes or other visible light emitters 64 is mounted along the underside of a sensor bar 16 c , suitably masked and focused to project downwardly from the sensor bar 16 c the narrow light band 62 aligned with the sensors 38 on the sensor bar 16 c so that the light band 62 lies on the same item 14 section which is housing its cross sectional contour determined from the sensor 38 signals . thus , the numeric value displayed at any time will correspond to the segment bounded on one side by the light band 62 . the light band 62 is readily visible on the surface of the item 14 to an observer even if he or she is standing some short distance away . this indication removes any problems with parallax effects and is precise enough to satisfy the interests of the on - looking person being served or the server . the sensor bar 16 c will also mount for example , acoustic , optical or other sensors ( not shown ) as described in the cross referenced patent application for determining the cross sectional contours of sections of the item 14 in order to enable calculation of volumes of selected segments of the item described therein . the narrow visible light band should be located to be aligned with the item section which is being scanned at that time by the contour sensors 38 in order to provide an accurate correspondence therebetween . an example of such an arrangement is shown in fig9 where visible light emitters 66 on the underside of a sensor bar 16 d are aligned with and placed between optical triangulation emitter - receiver 68 of a type described in the cross referenced co - pending application or other types of height or thickness sensors . it would also be possible to use visible light in the optical contour measuring sensors 68 themselves therein to project the readily seen narrow band of visible light onto the item 14 .
an apparatus and method for displaying the weight or cost of an uncut selected segment of an item involves passing a position indicating member over the item lying on a support surface . the position indicating member carries one or more sensors which generate signals corresponding to succeeding cross sectional contours of the item as the member is traversed along the item from a reference position to a selected other position over this item , defining the selected segment of the item . at the same time , a motion detector arrangement preferably comprised of one or more microelectromechanical accelerometer devices generates signals corresponding to motion of the position indicator support member as it is moved along the item . these signals are processed in a signal processor to determine the volume of the uncut selected segment of the item lying between selected successive positions of the indication member . each of these cumulative volume determinations are converted into numeric weight or price values based on the density factor for the particular type of item , whereby numeric weight and price values are displayed as the member is traversed along the item , thus enabling the operator to contemporaneously provide an on - looking consumer weight or price information before a particular segment is cut from the item . a visible light band is projected from the sensor bar onto a section of the item to clearly show the selected segment bounds corresponding to the numeric display to the onlooker .