CA1270377A - Meat grader - Google Patents
Meat graderInfo
- Publication number
- CA1270377A CA1270377A CA000486872A CA486872A CA1270377A CA 1270377 A CA1270377 A CA 1270377A CA 000486872 A CA000486872 A CA 000486872A CA 486872 A CA486872 A CA 486872A CA 1270377 A CA1270377 A CA 1270377A
- Authority
- CA
- Canada
- Prior art keywords
- value
- addresses
- signal
- address
- carcass
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
- G01B11/06—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness for measuring thickness ; e.g. of sheet material
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/02—Food
- G01N33/12—Meat; fish
Abstract
ABSTRACT
The present invention is a meat grader comprising a probe for insertion through a meat carcass to be graded, a light source, and a light sensitive apparatus associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted and/or retracted through the carcass, apparatus for generating a first signal representative of the amount of light detected by the light sensitive means, apparatus for generating a second signal each predetermined increment of axial movement of the probe through the carcass, and apparatus means for reading and storing the first signal each time the second signal is generated. By subtracting the addresses of the storage locations for the first signal and multiplying the difference by a constant an indication of the thickness of the lean meat and/or fat can be obtained.
The present invention is a meat grader comprising a probe for insertion through a meat carcass to be graded, a light source, and a light sensitive apparatus associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted and/or retracted through the carcass, apparatus for generating a first signal representative of the amount of light detected by the light sensitive means, apparatus for generating a second signal each predetermined increment of axial movement of the probe through the carcass, and apparatus means for reading and storing the first signal each time the second signal is generated. By subtracting the addresses of the storage locations for the first signal and multiplying the difference by a constant an indication of the thickness of the lean meat and/or fat can be obtained.
Description
~2~37~
01 This invention relates to apparatus used 02 to determine the thickness of meat and/or fat in a 03 carcass, and is usefully employed as a pork grader.
04 Farmers are paid for their meat carcasses, 05 often not only on the basis of total weight of the 06 carcasses, but also on the absolu~e or relative amount 07 o~ lean meat -to fat in the carcass. In order to 08 de-termine the absolute or relative thickness of lean 09 meat and fat, a probe is pushed into the carcass, the probe carrying a light source and photosensor adjacent 11 its tip for sensing whether the probe is passing 12 through meat or at. The amount o~ light reflected 13 from the surrounding tissue from the light source, as 14 sensed by the photosensor determines whether the sensor is embedded in lean meat or fat; fat reflects a 16 large amount of light while lean meat reflects a small 17 amount of light.
18 Such meat probes have been known and used 19 for many years, for example as described and claimed in Canadian Patent 1,157,257 issued 21 November 22nd, 1983 to Hennessy et al and Canadian 22 Patent 1,075,457 issued April 15th, 1982 to Hennessy.
23 In both the aforenoted patents a probe 24 carrying a light and photosensor as described above are pushed through the flesh of a carcass. As the 26 probe moves through the carcass the position of the 27 interfaces between highly and poorly reflective meat 28 are noted. A mechanical plate supported at the 29 surface of the carcass is linked to a position measuring apparatus, i.e. a distance scale. The 31 distance that the probe moves between the aforenoted 32 interfaces provides the operator an indication of the 33 thickness of the meat and/or fat.
34 In Canadian Patent 1,075,457 a mechanical scale is controlled by the movement of the probe 36 relative to the plate which rests on the surface oE
37 the carcass. The operator zeroes and notes the scale r; ~r ~7~3~
01 values. However in this apparatus I have determined 02 that inaccuracies can occur due to operator error in 03 setting the scale and in reading the scale. The 04 mechanica] manner of linkage o~ the scale to the 05 moving parts also can introduce errors due to wear of 06 the apparatus.
07 In Canadian patent 1,157,257 signals 08 representing the maximum and minimum amounts of light 09 received by the light sensitive elements are stored in a pair of capacitors. These reflectance values are 11 set when the probe is inserted into -the carcass. The 12 circuit automatically sets an intermediate level to 13 establish the interface signal level between lean and 14 fat meat. A second light source - light sensitive element pair are located adjacènt a grid, which causes 16 the light sensitive element to pulse as the grid 17 passes between them when the meat probe is withdrawn.
18 By counting the number of pulses between the selected 19 intermediate voltage level and the ambient outside of -the carcass, the depth of the outer fat level is 21 determined. In the latter patent it is only possible 22 to determine the outer fat thickness, and not the 23 thickness of the lean mea-t. Further, the maximum and 24 minimum signal values are stored on a pair of capacitors, which can leak and thus can give rise to 26 erroneous readings. Further, the intermediate voltage 27 level is arbitrarily set, and due to the possible 28 interleaving of fat and lean meat, it is possible to 2g indicate an erroneous outer fat layer. In addition, the aforenoted patent measures the thickness by a 31 direct physical determination by the position of the 32 probe. Because the signal levels stored are analog in 33 nature, they can drift, and can be rendered inaccurate.
34 The present invention, on the other hand, can determine the thickness of both the meat and fat 36 layers (and/or their sum) with a high degree of 37 accuracy. Signals corresponding to the reflected ,~
~L~7~3377 01 light values are stored in a digital memory. Rather 02 than setting a val.ue arbitrarily between the highest ~3 and lowest reflectance values, I have determined that 04 a more accurate indication of the interface between 05 fat and lean meat can be obtained by operating on the 06 slope, tha~ is the rate of change of the reflected 07 light signal. The term reflectance value as used 08 herein is intended to mean the light signal level 09 received by the photosensor reflected by the carcass from the light source.
ll ~ather than providing a mechanical 12 distance measuring apparatus as in the ~ennessy 13 patents, the present invention does not concern itself 14 with the absolute position of the probe or distance measuring mechanical parts, and thus does not measure 16 the fat layer thickness directly from a base point as 17 the probe is withdrawn as in Hennessy. The presen-t 18 invention requires only that there should be relative 19 movement between the probe and an apparatus which moves as the probe is inserted and withdrawn from the 21 carcass. This relative movement causes regular 22 readings to be taken of the reflectance values at 23 positions related to increments of movement, rather 24 than at absolute positions. Thus there is no need to indicate a first signal reading position of'the probe 26 or mechanical distance measuring apparatus, with the 27 attendant mechanical linkage errors, as in the 28 aforenoted prior art patents.
2g Further, since all readings taken are digitally stored, they can be moved to archival memory 31 for later recall in case of dispute between the farmer 32 and marketing organization, the total or accumulative 33 amounts of meat supplied by the farmer can be 34 established and kept by the present apparatus, and the thickness values can be printed on a printer or 36 transmitted to a digital computer.
37 In general, the invention is a meat yrader 38 - 3 ~
~i,i ~7~37~7 01 comprising a probe for insertion through a meat 02 carcass to be graded, a light source, and a light 03 sensitive apparatus associated with the probe for 04 detecting light from the light source reflected from 05 the meat carcass as the probe is inserted and/or 06 retracted through the carcass, apparatus for 07 generating a first signal representative of the amount 08 of li.ght detected by the light sensitive apparatus, 09 apparatus for generating a second signal each predetermined increment of axial movement of the probe 11 through the carcass, and apparatus for reading the 12 first signal each time the second signal is generated, 13 and for storing each read first signal. Further 14 apparatus determines the thickness of lean meat represented by a stored low light reflection value or 16 the thickness of fat meat represented by a stored high 17 light reflection value comprising apparatus for 18 establishes the addresses of stored signals 19 representing the interfaces between low and high light values, apparatus for determining the the number of 21 first signals stored between the addresses, and 22 apparatus for multiplying the number of first signals 23 stored between the addresses by a predetermined 24 constant to provide lean or fat meat thickness representation signals for storage or display.
26 Another embodiment of the invention is a 27 meat grader comprising a probe for insertion through a 28 meat carcass to be graded, a light source, and a light 29 sensitive apparatus associated with the probe for detecting light from the light source reflected from 31 the meat carcass as the probe is inserted or retracted 32 through the carcass, apparatus for generating a first 33 signal representative of the amount of light detected 34 by the light sensitive apparatus, apparatus for generating a second signal each predetermined 36 increment of axial movement of the probe through the 37 _ 4 _ , ~ , . .
,.
01 carcass, apparatus for reading the first signal each 02 time the second signal is generated, and for storing 03 each read first signal in a memory at addresses 04 corresponding to the second signals~ and further 05 comprising apparatus for reading the stored first 06 signals, and for determining a high positive rate of 07 change in stored values at successive addresses, and 08 for establishing a first reference signal value at an 09 address location having a low signal level just prior to the addresses having ~he high rate of change 11 values, determining a second reference signal value at 12 an address having a value related to a predetermined 13 minimum negative rate of change in the values with 14 increasing addresses, determining a third reference signal value at the first address higher than that of 16 the second reference point following a range of 17 increasing values with increasing addresses, which 18 contains a value equivalent to that at the second 19 reference point, or a value a predetermined amount less than the value equivalent to the second re~erence 21 point, whichever is the greater, apparatus for 22 subtracting the addresses of the first and second 23 reference points and multiplying the difference by a 24 constant to obtain a signal representative of fat content of a carcass, and for subtracting the 26 addresses of the second and third reference points and 27 multiplying the difference by a constant to obtain a 28 signal representative of lean meat content of a 29 carcass, and apparatus for providing the representative signals for display or storage.
31 Another embodiment of the invention is a 32 meat grader comprising a probe for insertion through a 33 meat carcass to be graded, a light source, and a light 34 sensitive apparatus associated with the probe for detecting light from the light source reflected from 36 the meat carcass as the probe is inserted or retracted 37 - 4a -~2~
01 through the carcass, apparatus for generating a first 02 signal representative of the amount of light detected 03 by the light sensi.tive apparatus, apparatus for 04 generating a second signal each predetermined 05 increment of axial movement of the probe through the 06 carcass, apparatus for reading the first signal each 07 time the second signal is generated, and for storing 08 each read Eirst signal in a memory at addresses 09 corresponding to the second signals, and further comprising apparatus for reading the stored first 11 signals, and for determining a high positive rate of 12 change in stored values at successive addresses, and 13 for establishing a first reference signal value at an 14 address location having a low signal level just prior to the addresses having the high rate of change 16 values, determining a first marker value "a" at an 17 address location higher than the first reference value 18 where the rate of change of stored values has 19 decreased by a predetermined amount over a predetermined number of values having increasing 21 addresses, determining a second marker value "b" at an 22 address higher than the address of the first marker 23 value where the value is increasing or has remained 24 constant over a predetermined number of increasing addresses, determining a third marker value "c" at the 26 address containing the largest value between the first 27 marker value and a value at an address a predetermined 28 number of addresses preceding, and establishing a 29 second reference signal value at the address midway between the addresses containing the second and third 31 marker values, establishing a third reference signal 32 value at the first address higher than that of the 33 second marker value which contains a value equivalent 34 to that at the second reference point or a value a predetermined amount less than the value equivalent to 36 the second reference point, whichever is the greater, 37 - 4b -.. : .
.
~`'7~7~7 01 and apparatus for transmitting the first, second and ~2 third reference signals via a communication line to a 03 printer or a remote terminal.
04 ~nother embodiment of the invention is a 05 meat grader comprising a probe for insertion through a 06 meat carcass to be graded, a light source, and a light 07 sensitive apparatus associated with the probe for 08 detecting light from the light source reflected from 09 the meat carcass as the probe is inserted or retracted through the carcass, apparatus for generating a first 11 signal representative of the amount of light detected 12 by the light sensitive apparatus, apparatus for 13 generating a second signal each predetermined 14 increment of axial movement of t~le probe through the carcass, apparatus for reading the first signal each 16 time the second signal is generated, and for storing 17 each read first signal in a memory at addresses 18 corresponding to the second signals, and further 19 comprising apparatus for reading the stored first signals, and for determining a high rate of change in 21 stored values at successive addresses, and for 22 establishing a first reference signal value at an 23 address location having a low signal level just prior 24 to the addresses having the high rate of change values, determining a first marker value "a" at an 26 address location higher than the first reference value 27 where the rate of change of stored values has 28 decreased by a predetermined amount over a 29 predetermined number of values having increasing addresses, determining a second marker value "bl' at an 31 address higher than the address of the first marker 32 value where the value is increasing or has remained 33 constant over a predetermined number of increaslng 34 addresses, determining a third marker value l'c" at an address containing the largest value between the first 36 marker value and a value at an address a predetermined 37 - 4c -1'~'7~3~
01 number of addresses preceding, and establishing a 02 second reference signal value at the address midway 03 between the addresses containing the second and third 04 marker values, establishing a third reference signal 05 value at the ~irst address ~igher than that of the 06 second marker value which contains a value equivalent 07 to that at the second reference point or a value a 08 predetermined amount less than a value equivalent to 09 the second reference signal value, whichever is the greater, apparatus for subtracting the addresses of 11 the first and second reference signal values and 12 multiplying the difference by a constant to obtain a 13 signal representative of fat content of a carcass, and 14 for subtracting the addresses of the second and third lS reference signal values and multiplying the difference 16 by a constant to obtain a signal representative of 17 lean meat content of a carcass, and apparatus for 18 providing the representative signals for display or 19 storage.
Another embodiment of the invention is a 21 meat grader comprising a probe for insertion through a 22 meat carcass to be graded, a light source, and a light 23 sensitive apparatus associated with the probe for 24 detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted 26 through the carcass, apparatus for generating a first 27 signal representative of the amount of light detected 28 by the light sensitive apparatus, apparatus for 29 generating a second signal each predetermined increment of axial movement of the probe through the 31 carcass, apparatus for reading the first signal each 32 time the second signal is generated, and for storing 33 each read first signal in a memory at addresses 34 corresponding to the second signals, and representative signals generated therein, and 37 - 4d -,~
~, . . .
.~ .
~L~71~
01 including a light emitting diode light source 02 connected to the input of a first analog to digital 03 converter, the Olltput of the converter being connected 04 to the data input of a digital memory, a photosensor 05 connected to the input of a second analog to digital 06 converter, the output of the second converter being 07 connected to the input of an address selector, the 08 output of the address selector being connected to the 09 address input of the memory, a microprocessor connected to the address selector, the memory and the 11 analog to digital converters for enabling the 12 converters, and for controlling the address selector 13 and memory, whereby the ~irst signals are stored at 14 addresses represented by the second signals.
Another embodiment of the invention is a 16 method of grading a carcass comprising obtaining the 17 light reflectivity of the meat in a carcass at 18 progressive depths within the meat, storing digital 19 signals representative of the reflectivity at successive memory addresses representative of a 21 relative location of the particular reflectivity from 22 an indeterminate position outside the meat to an 23 indeterminate depth within the meat, determining a 24 high rate of change in stored values at successive addresses, and establishing a first reference signal 26 value at an address having a low signal level just 27 prior to the addresses having the high rate of change 28 values, determining a second reference signal value at 29 an address storing a value related to a predetermined minimum negative rate of change in the values with 31 increasing addresses, determining a third reference 32 signal value at the first address higher than that of 33 the second reference signal value following a range o~
34 increasing values with increasing addresses, which contains a value equivalent to that at the second 36 reference point, or a value a predetermined amount 37 - 4e -01 less than the value equivalent to the second reference Q2 point, whichever is the greater, and for subtracting 03 the addresses of the first and second reference point 04 and multiplying the difference by a constant to obtain 05 a signal representative of Eat content of a carcass, 06 and ~or subtracting the second and thlrd addresses and 07 multiplying the difference by a constant to obtain a 08 signal representative of lean meat content of a 09 carcass, and apparatus for providing the representative signals for display or storage.
11 A better understanding of this invention 12 will be obtained by the detailed description below 13 with reference to the following drawings, in which: -14 Figure 1 is a perspective view of a meat probe, 16 Figures 2 and 3 are a side sectional view 17 and a top mechanical view illustrating details of the 18 invention, 19 Figure 4 is a block diagram of the electronic portion of the invention, and 21 Figure 5 is a graph showing readings of 22 reflectance values which are stored in the memory of 23 the present invention.
24 Referring first to Figure 1, a pointed probe 1 is fixed to and extends forwardly of a housing 26 2 to which a carrying handle 3 also is fixed. ~n 27 aiming plate 4 is fixed to the front of a pair of 28 shafts 5 which extend through apertures 6 in the front 29 wall of the housing 2. The probe 1 fixed to the housing extends through an aperture 7 in the aiming 31 plate 4. ~ light source 8 and a photosensor 9 are 32 embedded within the probe close to the tip, and are 33 light-accessible at the surface thereof.
34 In operation, the probe tip is inserted 36 - 4~ -.:.. ,.. 1: .;
~7~;~ ,7~
01 into the carcass and is pushed through the meat and 02 fa-t to the bone area. The aiming plate 4 rests at the 03 surEace of the carcass, causing shafts 5 to move 04 through the apertures 6 in the housing 2. According 05 to the prior art, the relative posi-tion o~ the aiming 06 plate 4 to the proba was directly measured, in 07 Canadian patent 1,075,457 for example by the use of a 08 mechanical gauge, and in Canadian patent 1,157,257 by 09 an elec-tronic counter which begins incrementing and thus measuring the position at a predetermined signal 11 level inter~ediate the highest and lowest signal 12 levels detected on the photosensor. The thickness of 13 the meat was determined by a count of pulses stored in 14 the counter, each pulse being directly related to the position of the aiming plate relative to the probe.
16 In the present invention determination of 17 the absolute position of the aiming plate relative to 18 the probe is avoided, in order to reduce or eliminate 19 the mechanical inaccuracy problems described earlier.
The position of the aiming plate in the present 21 invention merely causes readings of the signal value 22 received from the photosensor to be taken and stored.
23 Determination of the thickness of the lean meat and/or 24 fat is determined in a microprocessor, operating on the stored signal values.
26 In the present invention a potentiometer 27 is rotated by movement of the aiming plate; a DC
28 current is applied to the potentiometer resulting in 29 an analog output signal to be generated across the sliding tap and one terminal of the potentiometer in a 31 well known manner. This output signal is applied to 32 an analog-to-digital converter. The potentiometer's 33 rotation is calibrated so that preferably 0.55 ~m 34 movement of the aiming plate causes a 1 bit change in the output signal from the analog-to-digital 36 converter. The use of the above will be explained 37 below, but first the mechanical structure to produce :~, '' ' ~. ~
. ~ .....
:
3'77 01 the above will be described with reference to Figures 02 2 and 3.
03 Figure 2 i:Llustrates a vertical section 04 thr~ugh the housing showing the aiming plate, a shaft 05 5 and the apparatus important to illust:rate the 06 principles of the mechanical structure. Aiming plate 07 4 is shown coupled to shaft 5 which ext:ends through 08 aperture 6 in the front wall of housing 2. A
09 potentiometer 10 has its rotational shaft axially coupled to a pulley 11 and is mounted in an axis 11 orthogonal to the axis of shaft 5. A flexible strap 12 12 is fastened to the pulley at its end 13, the other 13 end 14 of the strap being fixed to a cross brace 15 14 which is fixed to and couples both shafts 5. Thus as aiming plate 4 is pushed toward the housing 2, shafts 16 5 extend further into the housing, pulling strap 12, 17 and rotating pulley 11.
18 A bushing 16 extends axially from and is 19 fixed to the pulley 11, and a second strap or wire 17 which is fixed to an extension spring 18 is wound in 21 the opposite direction to strap 12 around bushing 16.
22 The other end of spring 18 is fixed at a fixing point 23 19 to the housing. Thus as the pulley rotates as the 24 aiming Plate 14 extends into the housing, spring 18 is stretched, causing a counter restoring force against 26 the direction of movement of aiming plate 14.
27 Potentiometer 10 has its shaft coaxially fixed to 28 bushing 16 and pulley 11, and is itself fixed to the 29 housing 2. Thus as aiming plate 4 is pushed into the housing, as pulley 11 rotates, the sha-ft of 31 potentiometer 10 rotates.
32 Turning now to Figure 4, a block schematic 33 circuit of the invention is illustrated.
34 Potentiometer 10 is shown as a block, but it wilL be understood that a constant current is applied to it, 36 resulting in an output voltage dependent on the 37 position of the rotor or shaft of the potentiometer.
, ~
. ..
, . :
.
.~ . ' .
~7~37~7 01 Also a light source 8 (preferably a light emi-tting 02 diode) has a constant current source 20 connected to 03 cause it to illuminate in a well known manner. A
04 photosensor 9, preferably a phototransistor, receives 05 the light from light source 8 reflected from the 06 carcass, also in a well known manner.
07 The output o phototransistor 9 is 08 connected to an analog~to-digital converter 21, which 09 has its output connected to the data input of a memory 22. The output of potentiometer 10 is connected to 11 analog-to-digital converter 23 which has its output 12 connected to the input of an address selector 24. A
13 microprocessor 25 is connected to the 14 analog-to-digital converters 21 and 23, to address selector 24 and to memory 22, in order to operate them 16 in accordance with the algorithm to be described 17 below.
18 Preferably a keyboard 26 and a display 27 19 are connected to microprocessor 25, the keyboard being used for inputting data such as farmer number, carcass 21 unit number, etc. for storage in memory 22, and 22 display 27 being used for communication with the 23 operator, e.g. providing instantaneous readouts of the 24 light reflectance signal, meat thickness, or other instructions, if desired, rather than merely storing 26 them for later display or recording in other 27 apparatus. ~icroprocessor 25 also has an input-output 28 port shown as lead I/0, for providing an output signal 29 of carcass number, and/or farmer number and lean meant/fat thicknesses to a storage computer, to a 31 . printer, or other peripheral apparatus.
32 As indicated earlier, the potentiometer's 33 rotation is calibrated so that preferably O.S mm 34 movement of the aiming plate causes 1 bit change in the output of analog to-digital converter 23. It has 36 been found that a 2000 ohm potentiometer is suitable, ., ~
., ~ .
7~377 01 and the analog-to-digital converter should have a 02 resolution selected -to achieve the above.
03 Microprocessor 25 monitors the output of 04 analog-to-digital converter 23 and each time there is 05 a 1 bit change in its output, due to rotation of the 06 potentiometer 10, it enables the address selector 24 07 to read the output of the analog-to-digital converter 08 23. The resulting address signal is then applied to 09 the input of memory 22, which is also a-t that time enabled to read the output of analog-to-digital 11 converter 21 by microprocessor 25.
12 The analog output signal of photosensor 9 13 is applied to analog-to-digital converter 21, which 14 converts it to a digital signal. At the time of addressing memory 22 the mi.croprocessor 25 also causes 16 the analog-to-digital converter 21 (or a latch at its 17 output) to output its signal as a data signal to the 18 data inputs of memory 22. Memory 22 thus stores the 19 digital signal level read at the address indicated by address selector 24.
21 In the above manner a complete sequence of 22 readings will be obtained and stored in memory 22 as 23 the probe is inserted and/or retracted from the 24 carcass.
Figure 5 illustrates a continuous graph of 26 signal value stored at each me~ory location. The 27 graph consists of a series oE stepped amplitude 28 levels, each step corresponding to a specific 29 reading. Thus the axis "successive readings"
corresponds directly to memory locations, while the 31 signal value amplitude represents the digital value of 32 the stored signal at each memory location resulting 33 from the photosensor.
34 Looking from left to right, it may be seen that a very low signal level, representing very low 36 reflectance (the probe being external to the carcass) 37 is first stored at low addresses, followed by high , .
.
~L270~77 01 readings which represents the outer layer of fat.
02 Once the probe has entered a lean meat region, the 03 signal level drops to a low l.evel ex~ending over a 04 range indicated by L. The reflec-tance then increases 05 again as the pho-tosensor reaches the bone and sinew 06 region where there are additional regions of fat.
07 It is desired to determine various signal 08 level reference points in order to determine where the 09 meat and/or fat and/or ambient interfaces occur.
A first reference point (value and 11 address) determines the sensed ligh-t value when the 12 photosensor enters or leaves the carcass outer at 13 layer. This reference point "o" can be determined by 14 several possible means, the preferred one of which is to determine the interface between the very low light 16 value and a high increase rate of change of light 17 (i.e. a high slope). Alternatively an absolute low 18 light value can be used.
19 In order to determine a second reference point, first a point "a" is determined when the li~ht 21 value has decreased by a value o~ 60 or more units 22 over a distance of 3 mm from a peak following the 23 point "0". The microprocessor then searches for a 24 point "b" where the light value is increasing or has been constant ~or three successive readings. This 26 point "b" is interpreted as the light value for the 27 lean meat (low reflection).
2s3 A point "c" is then determined which is 29 the largest light value between "a" and preferably six readings prior to "a".
31 The second reference point (ref 2nd) is 32 established where the middle light value between 33 points "b" and "c" crosses the curve (which will often 34 be close to point "a"). This establishes the fat to lean meat interface.
36 A third reference point is established 37 where the same light value as at the second reference 38 _ 9 _ ~?.
..
~L27~ 7 01 point crosses the curve a second time, i.e. at "d".
02 If no point is found, the light value of the second 03 reference point is reduced by an arbi-trary value e.g.
04 10 is used. This sequence should continue until the 05 -third reference point is found.
06 Thus it may be seen that the light signal 07 levels between the first and second reference points 08 are due to the outer layer of fat, and the light 09 signal levels between the second and third reference points are due to the lean meat. The light signal 11 levels between the first and third reference points 12 are caused by the combined thickness of fat and lean 13 meat.
14 Subtracting the addresses between the reference points, and multiplying the differences by a 16 constant thus provides an indication of the fat, lean 17 meat and total thicknesses. These signals can be 18 stored in the memory for later retrieval, successive 19 totals can be added, the values can be output via the I/0 port to a printer or computer, etc. It should be 21 understood that successive increasing memory addresses 22 is intended to mean increasing in either the positive 23 or negative direction.
24 The structure described above clearly has significant advantages over the prior art both in 26 manipulation and storage of data, and in the accuracy 27 of thickness measurement, and also since a direct
01 This invention relates to apparatus used 02 to determine the thickness of meat and/or fat in a 03 carcass, and is usefully employed as a pork grader.
04 Farmers are paid for their meat carcasses, 05 often not only on the basis of total weight of the 06 carcasses, but also on the absolu~e or relative amount 07 o~ lean meat -to fat in the carcass. In order to 08 de-termine the absolute or relative thickness of lean 09 meat and fat, a probe is pushed into the carcass, the probe carrying a light source and photosensor adjacent 11 its tip for sensing whether the probe is passing 12 through meat or at. The amount o~ light reflected 13 from the surrounding tissue from the light source, as 14 sensed by the photosensor determines whether the sensor is embedded in lean meat or fat; fat reflects a 16 large amount of light while lean meat reflects a small 17 amount of light.
18 Such meat probes have been known and used 19 for many years, for example as described and claimed in Canadian Patent 1,157,257 issued 21 November 22nd, 1983 to Hennessy et al and Canadian 22 Patent 1,075,457 issued April 15th, 1982 to Hennessy.
23 In both the aforenoted patents a probe 24 carrying a light and photosensor as described above are pushed through the flesh of a carcass. As the 26 probe moves through the carcass the position of the 27 interfaces between highly and poorly reflective meat 28 are noted. A mechanical plate supported at the 29 surface of the carcass is linked to a position measuring apparatus, i.e. a distance scale. The 31 distance that the probe moves between the aforenoted 32 interfaces provides the operator an indication of the 33 thickness of the meat and/or fat.
34 In Canadian Patent 1,075,457 a mechanical scale is controlled by the movement of the probe 36 relative to the plate which rests on the surface oE
37 the carcass. The operator zeroes and notes the scale r; ~r ~7~3~
01 values. However in this apparatus I have determined 02 that inaccuracies can occur due to operator error in 03 setting the scale and in reading the scale. The 04 mechanica] manner of linkage o~ the scale to the 05 moving parts also can introduce errors due to wear of 06 the apparatus.
07 In Canadian patent 1,157,257 signals 08 representing the maximum and minimum amounts of light 09 received by the light sensitive elements are stored in a pair of capacitors. These reflectance values are 11 set when the probe is inserted into -the carcass. The 12 circuit automatically sets an intermediate level to 13 establish the interface signal level between lean and 14 fat meat. A second light source - light sensitive element pair are located adjacènt a grid, which causes 16 the light sensitive element to pulse as the grid 17 passes between them when the meat probe is withdrawn.
18 By counting the number of pulses between the selected 19 intermediate voltage level and the ambient outside of -the carcass, the depth of the outer fat level is 21 determined. In the latter patent it is only possible 22 to determine the outer fat thickness, and not the 23 thickness of the lean mea-t. Further, the maximum and 24 minimum signal values are stored on a pair of capacitors, which can leak and thus can give rise to 26 erroneous readings. Further, the intermediate voltage 27 level is arbitrarily set, and due to the possible 28 interleaving of fat and lean meat, it is possible to 2g indicate an erroneous outer fat layer. In addition, the aforenoted patent measures the thickness by a 31 direct physical determination by the position of the 32 probe. Because the signal levels stored are analog in 33 nature, they can drift, and can be rendered inaccurate.
34 The present invention, on the other hand, can determine the thickness of both the meat and fat 36 layers (and/or their sum) with a high degree of 37 accuracy. Signals corresponding to the reflected ,~
~L~7~3377 01 light values are stored in a digital memory. Rather 02 than setting a val.ue arbitrarily between the highest ~3 and lowest reflectance values, I have determined that 04 a more accurate indication of the interface between 05 fat and lean meat can be obtained by operating on the 06 slope, tha~ is the rate of change of the reflected 07 light signal. The term reflectance value as used 08 herein is intended to mean the light signal level 09 received by the photosensor reflected by the carcass from the light source.
ll ~ather than providing a mechanical 12 distance measuring apparatus as in the ~ennessy 13 patents, the present invention does not concern itself 14 with the absolute position of the probe or distance measuring mechanical parts, and thus does not measure 16 the fat layer thickness directly from a base point as 17 the probe is withdrawn as in Hennessy. The presen-t 18 invention requires only that there should be relative 19 movement between the probe and an apparatus which moves as the probe is inserted and withdrawn from the 21 carcass. This relative movement causes regular 22 readings to be taken of the reflectance values at 23 positions related to increments of movement, rather 24 than at absolute positions. Thus there is no need to indicate a first signal reading position of'the probe 26 or mechanical distance measuring apparatus, with the 27 attendant mechanical linkage errors, as in the 28 aforenoted prior art patents.
2g Further, since all readings taken are digitally stored, they can be moved to archival memory 31 for later recall in case of dispute between the farmer 32 and marketing organization, the total or accumulative 33 amounts of meat supplied by the farmer can be 34 established and kept by the present apparatus, and the thickness values can be printed on a printer or 36 transmitted to a digital computer.
37 In general, the invention is a meat yrader 38 - 3 ~
~i,i ~7~37~7 01 comprising a probe for insertion through a meat 02 carcass to be graded, a light source, and a light 03 sensitive apparatus associated with the probe for 04 detecting light from the light source reflected from 05 the meat carcass as the probe is inserted and/or 06 retracted through the carcass, apparatus for 07 generating a first signal representative of the amount 08 of li.ght detected by the light sensitive apparatus, 09 apparatus for generating a second signal each predetermined increment of axial movement of the probe 11 through the carcass, and apparatus for reading the 12 first signal each time the second signal is generated, 13 and for storing each read first signal. Further 14 apparatus determines the thickness of lean meat represented by a stored low light reflection value or 16 the thickness of fat meat represented by a stored high 17 light reflection value comprising apparatus for 18 establishes the addresses of stored signals 19 representing the interfaces between low and high light values, apparatus for determining the the number of 21 first signals stored between the addresses, and 22 apparatus for multiplying the number of first signals 23 stored between the addresses by a predetermined 24 constant to provide lean or fat meat thickness representation signals for storage or display.
26 Another embodiment of the invention is a 27 meat grader comprising a probe for insertion through a 28 meat carcass to be graded, a light source, and a light 29 sensitive apparatus associated with the probe for detecting light from the light source reflected from 31 the meat carcass as the probe is inserted or retracted 32 through the carcass, apparatus for generating a first 33 signal representative of the amount of light detected 34 by the light sensitive apparatus, apparatus for generating a second signal each predetermined 36 increment of axial movement of the probe through the 37 _ 4 _ , ~ , . .
,.
01 carcass, apparatus for reading the first signal each 02 time the second signal is generated, and for storing 03 each read first signal in a memory at addresses 04 corresponding to the second signals~ and further 05 comprising apparatus for reading the stored first 06 signals, and for determining a high positive rate of 07 change in stored values at successive addresses, and 08 for establishing a first reference signal value at an 09 address location having a low signal level just prior to the addresses having ~he high rate of change 11 values, determining a second reference signal value at 12 an address having a value related to a predetermined 13 minimum negative rate of change in the values with 14 increasing addresses, determining a third reference signal value at the first address higher than that of 16 the second reference point following a range of 17 increasing values with increasing addresses, which 18 contains a value equivalent to that at the second 19 reference point, or a value a predetermined amount less than the value equivalent to the second re~erence 21 point, whichever is the greater, apparatus for 22 subtracting the addresses of the first and second 23 reference points and multiplying the difference by a 24 constant to obtain a signal representative of fat content of a carcass, and for subtracting the 26 addresses of the second and third reference points and 27 multiplying the difference by a constant to obtain a 28 signal representative of lean meat content of a 29 carcass, and apparatus for providing the representative signals for display or storage.
31 Another embodiment of the invention is a 32 meat grader comprising a probe for insertion through a 33 meat carcass to be graded, a light source, and a light 34 sensitive apparatus associated with the probe for detecting light from the light source reflected from 36 the meat carcass as the probe is inserted or retracted 37 - 4a -~2~
01 through the carcass, apparatus for generating a first 02 signal representative of the amount of light detected 03 by the light sensi.tive apparatus, apparatus for 04 generating a second signal each predetermined 05 increment of axial movement of the probe through the 06 carcass, apparatus for reading the first signal each 07 time the second signal is generated, and for storing 08 each read Eirst signal in a memory at addresses 09 corresponding to the second signals, and further comprising apparatus for reading the stored first 11 signals, and for determining a high positive rate of 12 change in stored values at successive addresses, and 13 for establishing a first reference signal value at an 14 address location having a low signal level just prior to the addresses having the high rate of change 16 values, determining a first marker value "a" at an 17 address location higher than the first reference value 18 where the rate of change of stored values has 19 decreased by a predetermined amount over a predetermined number of values having increasing 21 addresses, determining a second marker value "b" at an 22 address higher than the address of the first marker 23 value where the value is increasing or has remained 24 constant over a predetermined number of increasing addresses, determining a third marker value "c" at the 26 address containing the largest value between the first 27 marker value and a value at an address a predetermined 28 number of addresses preceding, and establishing a 29 second reference signal value at the address midway between the addresses containing the second and third 31 marker values, establishing a third reference signal 32 value at the first address higher than that of the 33 second marker value which contains a value equivalent 34 to that at the second reference point or a value a predetermined amount less than the value equivalent to 36 the second reference point, whichever is the greater, 37 - 4b -.. : .
.
~`'7~7~7 01 and apparatus for transmitting the first, second and ~2 third reference signals via a communication line to a 03 printer or a remote terminal.
04 ~nother embodiment of the invention is a 05 meat grader comprising a probe for insertion through a 06 meat carcass to be graded, a light source, and a light 07 sensitive apparatus associated with the probe for 08 detecting light from the light source reflected from 09 the meat carcass as the probe is inserted or retracted through the carcass, apparatus for generating a first 11 signal representative of the amount of light detected 12 by the light sensitive apparatus, apparatus for 13 generating a second signal each predetermined 14 increment of axial movement of t~le probe through the carcass, apparatus for reading the first signal each 16 time the second signal is generated, and for storing 17 each read first signal in a memory at addresses 18 corresponding to the second signals, and further 19 comprising apparatus for reading the stored first signals, and for determining a high rate of change in 21 stored values at successive addresses, and for 22 establishing a first reference signal value at an 23 address location having a low signal level just prior 24 to the addresses having the high rate of change values, determining a first marker value "a" at an 26 address location higher than the first reference value 27 where the rate of change of stored values has 28 decreased by a predetermined amount over a 29 predetermined number of values having increasing addresses, determining a second marker value "bl' at an 31 address higher than the address of the first marker 32 value where the value is increasing or has remained 33 constant over a predetermined number of increaslng 34 addresses, determining a third marker value l'c" at an address containing the largest value between the first 36 marker value and a value at an address a predetermined 37 - 4c -1'~'7~3~
01 number of addresses preceding, and establishing a 02 second reference signal value at the address midway 03 between the addresses containing the second and third 04 marker values, establishing a third reference signal 05 value at the ~irst address ~igher than that of the 06 second marker value which contains a value equivalent 07 to that at the second reference point or a value a 08 predetermined amount less than a value equivalent to 09 the second reference signal value, whichever is the greater, apparatus for subtracting the addresses of 11 the first and second reference signal values and 12 multiplying the difference by a constant to obtain a 13 signal representative of fat content of a carcass, and 14 for subtracting the addresses of the second and third lS reference signal values and multiplying the difference 16 by a constant to obtain a signal representative of 17 lean meat content of a carcass, and apparatus for 18 providing the representative signals for display or 19 storage.
Another embodiment of the invention is a 21 meat grader comprising a probe for insertion through a 22 meat carcass to be graded, a light source, and a light 23 sensitive apparatus associated with the probe for 24 detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted 26 through the carcass, apparatus for generating a first 27 signal representative of the amount of light detected 28 by the light sensitive apparatus, apparatus for 29 generating a second signal each predetermined increment of axial movement of the probe through the 31 carcass, apparatus for reading the first signal each 32 time the second signal is generated, and for storing 33 each read first signal in a memory at addresses 34 corresponding to the second signals, and representative signals generated therein, and 37 - 4d -,~
~, . . .
.~ .
~L~71~
01 including a light emitting diode light source 02 connected to the input of a first analog to digital 03 converter, the Olltput of the converter being connected 04 to the data input of a digital memory, a photosensor 05 connected to the input of a second analog to digital 06 converter, the output of the second converter being 07 connected to the input of an address selector, the 08 output of the address selector being connected to the 09 address input of the memory, a microprocessor connected to the address selector, the memory and the 11 analog to digital converters for enabling the 12 converters, and for controlling the address selector 13 and memory, whereby the ~irst signals are stored at 14 addresses represented by the second signals.
Another embodiment of the invention is a 16 method of grading a carcass comprising obtaining the 17 light reflectivity of the meat in a carcass at 18 progressive depths within the meat, storing digital 19 signals representative of the reflectivity at successive memory addresses representative of a 21 relative location of the particular reflectivity from 22 an indeterminate position outside the meat to an 23 indeterminate depth within the meat, determining a 24 high rate of change in stored values at successive addresses, and establishing a first reference signal 26 value at an address having a low signal level just 27 prior to the addresses having the high rate of change 28 values, determining a second reference signal value at 29 an address storing a value related to a predetermined minimum negative rate of change in the values with 31 increasing addresses, determining a third reference 32 signal value at the first address higher than that of 33 the second reference signal value following a range o~
34 increasing values with increasing addresses, which contains a value equivalent to that at the second 36 reference point, or a value a predetermined amount 37 - 4e -01 less than the value equivalent to the second reference Q2 point, whichever is the greater, and for subtracting 03 the addresses of the first and second reference point 04 and multiplying the difference by a constant to obtain 05 a signal representative of Eat content of a carcass, 06 and ~or subtracting the second and thlrd addresses and 07 multiplying the difference by a constant to obtain a 08 signal representative of lean meat content of a 09 carcass, and apparatus for providing the representative signals for display or storage.
11 A better understanding of this invention 12 will be obtained by the detailed description below 13 with reference to the following drawings, in which: -14 Figure 1 is a perspective view of a meat probe, 16 Figures 2 and 3 are a side sectional view 17 and a top mechanical view illustrating details of the 18 invention, 19 Figure 4 is a block diagram of the electronic portion of the invention, and 21 Figure 5 is a graph showing readings of 22 reflectance values which are stored in the memory of 23 the present invention.
24 Referring first to Figure 1, a pointed probe 1 is fixed to and extends forwardly of a housing 26 2 to which a carrying handle 3 also is fixed. ~n 27 aiming plate 4 is fixed to the front of a pair of 28 shafts 5 which extend through apertures 6 in the front 29 wall of the housing 2. The probe 1 fixed to the housing extends through an aperture 7 in the aiming 31 plate 4. ~ light source 8 and a photosensor 9 are 32 embedded within the probe close to the tip, and are 33 light-accessible at the surface thereof.
34 In operation, the probe tip is inserted 36 - 4~ -.:.. ,.. 1: .;
~7~;~ ,7~
01 into the carcass and is pushed through the meat and 02 fa-t to the bone area. The aiming plate 4 rests at the 03 surEace of the carcass, causing shafts 5 to move 04 through the apertures 6 in the housing 2. According 05 to the prior art, the relative posi-tion o~ the aiming 06 plate 4 to the proba was directly measured, in 07 Canadian patent 1,075,457 for example by the use of a 08 mechanical gauge, and in Canadian patent 1,157,257 by 09 an elec-tronic counter which begins incrementing and thus measuring the position at a predetermined signal 11 level inter~ediate the highest and lowest signal 12 levels detected on the photosensor. The thickness of 13 the meat was determined by a count of pulses stored in 14 the counter, each pulse being directly related to the position of the aiming plate relative to the probe.
16 In the present invention determination of 17 the absolute position of the aiming plate relative to 18 the probe is avoided, in order to reduce or eliminate 19 the mechanical inaccuracy problems described earlier.
The position of the aiming plate in the present 21 invention merely causes readings of the signal value 22 received from the photosensor to be taken and stored.
23 Determination of the thickness of the lean meat and/or 24 fat is determined in a microprocessor, operating on the stored signal values.
26 In the present invention a potentiometer 27 is rotated by movement of the aiming plate; a DC
28 current is applied to the potentiometer resulting in 29 an analog output signal to be generated across the sliding tap and one terminal of the potentiometer in a 31 well known manner. This output signal is applied to 32 an analog-to-digital converter. The potentiometer's 33 rotation is calibrated so that preferably 0.55 ~m 34 movement of the aiming plate causes a 1 bit change in the output signal from the analog-to-digital 36 converter. The use of the above will be explained 37 below, but first the mechanical structure to produce :~, '' ' ~. ~
. ~ .....
:
3'77 01 the above will be described with reference to Figures 02 2 and 3.
03 Figure 2 i:Llustrates a vertical section 04 thr~ugh the housing showing the aiming plate, a shaft 05 5 and the apparatus important to illust:rate the 06 principles of the mechanical structure. Aiming plate 07 4 is shown coupled to shaft 5 which ext:ends through 08 aperture 6 in the front wall of housing 2. A
09 potentiometer 10 has its rotational shaft axially coupled to a pulley 11 and is mounted in an axis 11 orthogonal to the axis of shaft 5. A flexible strap 12 12 is fastened to the pulley at its end 13, the other 13 end 14 of the strap being fixed to a cross brace 15 14 which is fixed to and couples both shafts 5. Thus as aiming plate 4 is pushed toward the housing 2, shafts 16 5 extend further into the housing, pulling strap 12, 17 and rotating pulley 11.
18 A bushing 16 extends axially from and is 19 fixed to the pulley 11, and a second strap or wire 17 which is fixed to an extension spring 18 is wound in 21 the opposite direction to strap 12 around bushing 16.
22 The other end of spring 18 is fixed at a fixing point 23 19 to the housing. Thus as the pulley rotates as the 24 aiming Plate 14 extends into the housing, spring 18 is stretched, causing a counter restoring force against 26 the direction of movement of aiming plate 14.
27 Potentiometer 10 has its shaft coaxially fixed to 28 bushing 16 and pulley 11, and is itself fixed to the 29 housing 2. Thus as aiming plate 4 is pushed into the housing, as pulley 11 rotates, the sha-ft of 31 potentiometer 10 rotates.
32 Turning now to Figure 4, a block schematic 33 circuit of the invention is illustrated.
34 Potentiometer 10 is shown as a block, but it wilL be understood that a constant current is applied to it, 36 resulting in an output voltage dependent on the 37 position of the rotor or shaft of the potentiometer.
, ~
. ..
, . :
.
.~ . ' .
~7~37~7 01 Also a light source 8 (preferably a light emi-tting 02 diode) has a constant current source 20 connected to 03 cause it to illuminate in a well known manner. A
04 photosensor 9, preferably a phototransistor, receives 05 the light from light source 8 reflected from the 06 carcass, also in a well known manner.
07 The output o phototransistor 9 is 08 connected to an analog~to-digital converter 21, which 09 has its output connected to the data input of a memory 22. The output of potentiometer 10 is connected to 11 analog-to-digital converter 23 which has its output 12 connected to the input of an address selector 24. A
13 microprocessor 25 is connected to the 14 analog-to-digital converters 21 and 23, to address selector 24 and to memory 22, in order to operate them 16 in accordance with the algorithm to be described 17 below.
18 Preferably a keyboard 26 and a display 27 19 are connected to microprocessor 25, the keyboard being used for inputting data such as farmer number, carcass 21 unit number, etc. for storage in memory 22, and 22 display 27 being used for communication with the 23 operator, e.g. providing instantaneous readouts of the 24 light reflectance signal, meat thickness, or other instructions, if desired, rather than merely storing 26 them for later display or recording in other 27 apparatus. ~icroprocessor 25 also has an input-output 28 port shown as lead I/0, for providing an output signal 29 of carcass number, and/or farmer number and lean meant/fat thicknesses to a storage computer, to a 31 . printer, or other peripheral apparatus.
32 As indicated earlier, the potentiometer's 33 rotation is calibrated so that preferably O.S mm 34 movement of the aiming plate causes 1 bit change in the output of analog to-digital converter 23. It has 36 been found that a 2000 ohm potentiometer is suitable, ., ~
., ~ .
7~377 01 and the analog-to-digital converter should have a 02 resolution selected -to achieve the above.
03 Microprocessor 25 monitors the output of 04 analog-to-digital converter 23 and each time there is 05 a 1 bit change in its output, due to rotation of the 06 potentiometer 10, it enables the address selector 24 07 to read the output of the analog-to-digital converter 08 23. The resulting address signal is then applied to 09 the input of memory 22, which is also a-t that time enabled to read the output of analog-to-digital 11 converter 21 by microprocessor 25.
12 The analog output signal of photosensor 9 13 is applied to analog-to-digital converter 21, which 14 converts it to a digital signal. At the time of addressing memory 22 the mi.croprocessor 25 also causes 16 the analog-to-digital converter 21 (or a latch at its 17 output) to output its signal as a data signal to the 18 data inputs of memory 22. Memory 22 thus stores the 19 digital signal level read at the address indicated by address selector 24.
21 In the above manner a complete sequence of 22 readings will be obtained and stored in memory 22 as 23 the probe is inserted and/or retracted from the 24 carcass.
Figure 5 illustrates a continuous graph of 26 signal value stored at each me~ory location. The 27 graph consists of a series oE stepped amplitude 28 levels, each step corresponding to a specific 29 reading. Thus the axis "successive readings"
corresponds directly to memory locations, while the 31 signal value amplitude represents the digital value of 32 the stored signal at each memory location resulting 33 from the photosensor.
34 Looking from left to right, it may be seen that a very low signal level, representing very low 36 reflectance (the probe being external to the carcass) 37 is first stored at low addresses, followed by high , .
.
~L270~77 01 readings which represents the outer layer of fat.
02 Once the probe has entered a lean meat region, the 03 signal level drops to a low l.evel ex~ending over a 04 range indicated by L. The reflec-tance then increases 05 again as the pho-tosensor reaches the bone and sinew 06 region where there are additional regions of fat.
07 It is desired to determine various signal 08 level reference points in order to determine where the 09 meat and/or fat and/or ambient interfaces occur.
A first reference point (value and 11 address) determines the sensed ligh-t value when the 12 photosensor enters or leaves the carcass outer at 13 layer. This reference point "o" can be determined by 14 several possible means, the preferred one of which is to determine the interface between the very low light 16 value and a high increase rate of change of light 17 (i.e. a high slope). Alternatively an absolute low 18 light value can be used.
19 In order to determine a second reference point, first a point "a" is determined when the li~ht 21 value has decreased by a value o~ 60 or more units 22 over a distance of 3 mm from a peak following the 23 point "0". The microprocessor then searches for a 24 point "b" where the light value is increasing or has been constant ~or three successive readings. This 26 point "b" is interpreted as the light value for the 27 lean meat (low reflection).
2s3 A point "c" is then determined which is 29 the largest light value between "a" and preferably six readings prior to "a".
31 The second reference point (ref 2nd) is 32 established where the middle light value between 33 points "b" and "c" crosses the curve (which will often 34 be close to point "a"). This establishes the fat to lean meat interface.
36 A third reference point is established 37 where the same light value as at the second reference 38 _ 9 _ ~?.
..
~L27~ 7 01 point crosses the curve a second time, i.e. at "d".
02 If no point is found, the light value of the second 03 reference point is reduced by an arbi-trary value e.g.
04 10 is used. This sequence should continue until the 05 -third reference point is found.
06 Thus it may be seen that the light signal 07 levels between the first and second reference points 08 are due to the outer layer of fat, and the light 09 signal levels between the second and third reference points are due to the lean meat. The light signal 11 levels between the first and third reference points 12 are caused by the combined thickness of fat and lean 13 meat.
14 Subtracting the addresses between the reference points, and multiplying the differences by a 16 constant thus provides an indication of the fat, lean 17 meat and total thicknesses. These signals can be 18 stored in the memory for later retrieval, successive 19 totals can be added, the values can be output via the I/0 port to a printer or computer, etc. It should be 21 understood that successive increasing memory addresses 22 is intended to mean increasing in either the positive 23 or negative direction.
24 The structure described above clearly has significant advantages over the prior art both in 26 manipulation and storage of data, and in the accuracy 27 of thickness measurement, and also since a direct
2~ reading of thickness does not depend on a measurement 29 of absolute aiming plate position.
A person understanding this invention may 31 now conceive of alternative variations based on the 32 principles described herein. All are considered to be 33 within the sphere and scope of this invention as 34 defined in the claims appended hereto.
.,~
A person understanding this invention may 31 now conceive of alternative variations based on the 32 principles described herein. All are considered to be 33 within the sphere and scope of this invention as 34 defined in the claims appended hereto.
.,~
Claims (9)
1. A meat grader comprising:
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by -the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) means for determining the thickness of lean meat represented by a stored low light reflection value or the thickness of fat meat represented by a stored high light reflection value comprising means for establishing the addresses of stored signals representing the interfaces between low and high light values, means for determining the number of first signals stored between the addresses, and means for multiplying the number of first signals stored between the addresses by a predetermined constant to provide lean or fat meat thickness representation signals for storage or display.
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by -the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) means for determining the thickness of lean meat represented by a stored low light reflection value or the thickness of fat meat represented by a stored high light reflection value comprising means for establishing the addresses of stored signals representing the interfaces between low and high light values, means for determining the number of first signals stored between the addresses, and means for multiplying the number of first signals stored between the addresses by a predetermined constant to provide lean or fat meat thickness representation signals for storage or display.
2. A meat grader comprising:
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high positive rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a second reference signal value at an address having a value related to a predetermined minimum negative rate of change in said values with increasing addresses, (iii) determining a third reference signal value at the first address higher than that of the second reference point following a range of increasing values with increasing addresses, which contains a value equivalent to that at the second reference point, or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, means for subtracting the addresses of the first and second reference points and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the addresses of the second and third reference points and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high positive rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a second reference signal value at an address having a value related to a predetermined minimum negative rate of change in said values with increasing addresses, (iii) determining a third reference signal value at the first address higher than that of the second reference point following a range of increasing values with increasing addresses, which contains a value equivalent to that at the second reference point, or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, means for subtracting the addresses of the first and second reference points and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the addresses of the second and third reference points and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
3. A meat grader comprising:
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high positive rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at the address containing the largest value between the first marker value and a value at an address a predetermined number of addresses preceding, and establishing a second reference signal value at the address midway between the addresses containing the second and third marker values, (iii) establishing a third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, and means for transmitting said first, second and third reference signals via a communication line to a printer or a remote terminal.
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high positive rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at the address containing the largest value between the first marker value and a value at an address a predetermined number of addresses preceding, and establishing a second reference signal value at the address midway between the addresses containing the second and third marker values, (iii) establishing a third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, and means for transmitting said first, second and third reference signals via a communication line to a printer or a remote terminal.
4. A meat grader comprising:
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at an address containing the largest value between the first marker value and a value at an address a predetermined number of addresses preceding, and establishing a second reference signal value at the address midway between the addresses containing the second and third marker values, (iii) establishing a third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than a value equivalent to the second reference signal value, whichever is the greater, means for subtracting the addresses of the first and second reference signal values and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the addresses of the second and third reference signal values and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and (f) further comprising means for reading the stored first signals, and for (i) determining a high rate of change in stored values at successive addresses, and for establishing a first reference signal value at an address location having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at an address containing the largest value between the first marker value and a value at an address a predetermined number of addresses preceding, and establishing a second reference signal value at the address midway between the addresses containing the second and third marker values, (iii) establishing a third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than a value equivalent to the second reference signal value, whichever is the greater, means for subtracting the addresses of the first and second reference signal values and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the addresses of the second and third reference signal values and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
5. A meat grader as defined in claim 4 further including means for transmitting said representative signals to a printer or a remote terminal.
6. A meat grader as defined in claim 4 including a light emitting diode light source connected to the input of a first analog to digital converter, the output of the: converter being connected to the data input of a digital memory, a photosensor connected to the input of a second analog to digital converter, the output of the second converter being connected to the input of an address selector, the output of the address selector being connected to the address input of the memory, a microprocessor connected to the address selector, the memory and the analog to digital converters for enabling the converters, and for controlling the address selector and memory, whereby said first signals are stored at addresses represented by the second signals, and whereby said first signals can be read by the microprocessor at said addresses, and said representative signals generated therein.
7. A meat grader comprising:
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and representative signals generated therein, and (f) including a light emitting diode light source connected to the input of a first analog to digital converter, the output of the converter being connected to the data input of a digital memory, a photosensor connected to the input of a second analog to digital converter, the output of the second converter being connected to the input of an address selector, the output of the address selector being connected to the address input of the memory, a microprocessor connected to the address selector, the memory and the analog to digital converters for enabling the converters, and for controlling the address selector and memory, whereby said first signals are stored at addresses represented by the second signals.
(a) a probe for insertion through a meat carcass to be graded, (b) a light source, and a light sensitive means associated with the probe for detecting light from the light source reflected from the meat carcass as the probe is inserted or retracted through the carcass, (c) means for generating a first signal representative of the amount of light detected by the light sensitive means, (d) means for generating a second signal each predetermined increment of axial movement of the probe through the carcass, (e) means for reading the first signal each time the second signal is generated, and for storing each read first signal in a memory at addresses corresponding to the second signals, and representative signals generated therein, and (f) including a light emitting diode light source connected to the input of a first analog to digital converter, the output of the converter being connected to the data input of a digital memory, a photosensor connected to the input of a second analog to digital converter, the output of the second converter being connected to the input of an address selector, the output of the address selector being connected to the address input of the memory, a microprocessor connected to the address selector, the memory and the analog to digital converters for enabling the converters, and for controlling the address selector and memory, whereby said first signals are stored at addresses represented by the second signals.
8. A method of grading a carcass comprising:
(a) obtaining the light reflectivity of the meat in a carcass at progressive depths within the meat, (b) storing digital signals representative of said reflectivity at successive memory addresses representative of a relative location of the particular reflectivity from an indeterminate position outside the meat to an indeterminate depth within the meat, (c) (i) determining a high rate of change in stored values at successive addresses, and establishing a first reference signal value at an address having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a second reference signal value at an address storing a value related to a predetermined minimum negative rate of change in said values with increasing addresses, (iii) determining a third reference signal value at the first address higher than that of the second reference signal value following a range of increasing values with increasing addresses, which contains a value equivalent to that at the second reference point, or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, and means for subtracting the addresses of the first and second reference point and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the second and third addresses and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
(a) obtaining the light reflectivity of the meat in a carcass at progressive depths within the meat, (b) storing digital signals representative of said reflectivity at successive memory addresses representative of a relative location of the particular reflectivity from an indeterminate position outside the meat to an indeterminate depth within the meat, (c) (i) determining a high rate of change in stored values at successive addresses, and establishing a first reference signal value at an address having a low signal level just prior to the addresses having said high rate of change values, (ii) determining a second reference signal value at an address storing a value related to a predetermined minimum negative rate of change in said values with increasing addresses, (iii) determining a third reference signal value at the first address higher than that of the second reference signal value following a range of increasing values with increasing addresses, which contains a value equivalent to that at the second reference point, or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater, and means for subtracting the addresses of the first and second reference point and multiplying the difference by a constant to obtain a signal representative of fat content of a carcass, and for subtracting the second and third addresses and multiplying the difference by a constant to obtain a signal representative of lean meat content of a carcass, and means for providing said representative signals for display or storage.
9. A method as defined in claim 8, including:
determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at the address containing the largest value between the first marker value and the value at an address a predetermined number of addresses preceding, and establishing the second reference signal value at the address midway between the addresses containing the second and third marker values, and establishing the third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater.
determining a first marker value "a" at an address location higher than said first reference value where the rate of change of stored values has decreased by a predetermined amount over a predetermined number of values having increasing addresses, determining a second marker value "b" at an address higher than the address of the first marker value where the value is increasing or has remained constant over a predetermined number of increasing addresses, determining a third marker value "c" at the address containing the largest value between the first marker value and the value at an address a predetermined number of addresses preceding, and establishing the second reference signal value at the address midway between the addresses containing the second and third marker values, and establishing the third reference signal value at the first address higher than that of the second marker value which contains a value equivalent to that at the second reference point or a value a predetermined amount less than the value equivalent to the second reference point, whichever is the greater.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000486872A CA1270377A (en) | 1985-07-16 | 1985-07-16 | Meat grader |
| GB08617180A GB2179443A (en) | 1985-07-16 | 1986-07-15 | Meat grader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000486872A CA1270377A (en) | 1985-07-16 | 1985-07-16 | Meat grader |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1270377A true CA1270377A (en) | 1990-06-19 |
Family
ID=4130985
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000486872A Expired - Lifetime CA1270377A (en) | 1985-07-16 | 1985-07-16 | Meat grader |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA1270377A (en) |
| GB (1) | GB2179443A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK159839C (en) * | 1986-09-05 | 1991-04-29 | Slagteriernes Forskningsinst | SENSING UNIT FOR AUTOMATIC DETERMINATION OF QUALITY CHARACTERISTICS |
| DK163382C (en) * | 1990-02-28 | 1992-08-03 | Slagteriernes Forskningsinst | PROCEDURE FOR DETERMINING THE QUALITY CHARACTERISTICS OF INDIVIDUAL GROUPS |
| GB9110474D0 (en) * | 1991-05-15 | 1991-07-03 | Commission Meat & Livestock | Meat quality sensing apparatus |
| FR2691543B1 (en) * | 1992-05-22 | 1995-07-07 | Sydel | MEAT QUALITY MEASURING APPARATUS. |
| WO2007000166A1 (en) | 2005-06-27 | 2007-01-04 | Sfk Technology A/S | Recording of position-specific wavelength absorption spectra |
| CN104374716B (en) * | 2014-08-18 | 2017-05-17 | 浙江工商大学 | Spliced beef detection system and method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1549065A (en) * | 1976-11-13 | 1979-08-01 | Pigs Marketing Board Northern | Apparatus for measuring thuckness of a layer |
| GB1576582A (en) * | 1978-05-31 | 1980-10-08 | Pigs Marketing Board Northern | Muscle quality |
| DK167715B1 (en) * | 1978-12-08 | 1993-12-06 | Slagteriernes Forskningsinst | PROCEDURE FOR AD OPTICAL WAY TO DETERMINE THE MEAT / SPEECH RELATIONSHIP IN SUBJECTS SUCH AS ANIMAL OR PART OF ANIMALS |
-
1985
- 1985-07-16 CA CA000486872A patent/CA1270377A/en not_active Expired - Lifetime
-
1986
- 1986-07-15 GB GB08617180A patent/GB2179443A/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| GB8617180D0 (en) | 1986-08-20 |
| GB2179443A (en) | 1987-03-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4503707A (en) | Hygrometry probe | |
| CA2141553C (en) | Dual sensitivity stud sensor | |
| US4390956A (en) | Apparatus for correcting measured gas flow | |
| US5035064A (en) | Linear measuring devices | |
| US4257107A (en) | Measuring device | |
| US4263653A (en) | Digital RF wattmeter | |
| US6205672B1 (en) | Digital tire caliper | |
| CA1270377A (en) | Meat grader | |
| US4672750A (en) | Thread measurement tool | |
| US6898866B2 (en) | Digital display tape measuring device | |
| CA1303349C (en) | General-purpose measuring implement usable in the field, and its datatransfer method | |
| US6686585B2 (en) | Position encoder with scale calibration | |
| US6191371B1 (en) | Electronic formula processing scale | |
| US7775421B2 (en) | Device for determining the sex (gender) of fish by measurement of morphological characteristics | |
| US4749858A (en) | Nuclear measuring gauge with automatic detection of source depth | |
| CA2018806A1 (en) | Displacement servo gauge | |
| US4651147A (en) | Device for setting a numeric display | |
| GB2241060A (en) | "Electronic tape measure" | |
| US3354551A (en) | Land measuring device | |
| EP0156140B1 (en) | Thread measurement tool | |
| RU206025U1 (en) | Device for measuring phyllotaxis parameters | |
| CN218329952U (en) | On-spot mapping device is used to engineering cost | |
| EP0068638B1 (en) | Protractors | |
| KR900005455B1 (en) | Apparatus for measuring calories | |
| KR20040086886A (en) | A digital scale for home use |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |