[001] Produce may typically be washed and transported to processing facilities after harvest. Once at the processing facility, the produce can be inspected to confirm its suitability for commercial production. During inspection, defective produce (e.g., rotten, bruised) and produce not meeting certain criteria (e.g., size, color) may be culled from the production line at the processing facility. If unsuitable produce could be culled at or near the harvest site prior to washing, water resources and transportation costs could be reduced. Early characterization of food items or identification of defective food items may reduce processing costs, even for non-produce items.

[002] Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.

SUMMARY

[003] Techniques are generally described that include methods and systems. An example system may include a hopper configured to contain a plurality of food items, a chute coupled to the hopper and shaped to receive an individual one of the plurality of food items at an end of the chute, an electrical impedance tomography (EIT) sensor positioned to receive the individual one of the plurality of food items, the EIT sensor may be configured to apply a signal and measure a resulting signal from the individual one of the plurality of food items, and a sorting gate that may be configured to direct the individual one of the plurality of food items into a selected one of a plurality of outputs based in part on the resulting signal.

[004] An example method may include transporting an individual food item from a hopper into contact with an electrical impedance tomography sensor (an EIT sensor), applying a signal to the individual food item using the EIT sensor and measuring a resulting signal from the individual food item using the KIT sensor to provide EIT sensor signals, and routing the individual food item to a selected output based on the EIT sensor signals.

[005] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[006] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several examples in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings, in which:

Figure 1 is a block diagram of a system for sorting food items;

Figure 2 is a schematic illustration of a system for sorting food items;

Figure 3 is a schematic illustration of a portion of an EIT sensor;

Figure 4 is a block diagram of a portion of a system for sorting food items,

Figure 5 is a flowchart of an example method;

Figure 6 is a block diagram illustrating an example computer device; and Figure 7 is a block diagram illustrating an example computer program product, all arranged in accordance with at least some embodiments of the present disclosure.

DETAILED DESCRIPTION

[007] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative examples described in the detailed description, drawings, and claims are not meant to be limiting. Other examples may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, ail of which are implicitly contemplated herein.

[008] This disclosure is drawn, inter alia, to methods, systems, products, devices, and/or apparatus generally related to a system for sorting food items, which may include a hopper configured to contain a plurality of food items, a chute coupled to the hopper and shaped to receive an individual one of the plurality of food items at an end of the chute, an electrical impedance tomography (EIT) sensor positioned to receive the individual one of the plurality of food items, the EIT sensor configured to apply a signal and measure a resulting signal through at least a portion of the individual one of the plurality of food items, and a sorting gate configured to direct the individual one of the plurality of food items into a selected one of a plurality of outputs based in part on the signal.

[009] Figure 1 is a block diagram of a system for sorting food items 100, arranged in accordance with at least some embodiments described herein. Figure 1 shows hopper 102, chute 104, EIT sensor 106, optional additional sensors 107, computer system 108, sorting gate 110, and outputs 112, 114, and 116. The various components described in Figure 1 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[010] The hopper 102 may be located at or near the top of the system 100 in some embodiments. Multiple food items may be placed in the hopper 102 at a time. For example, workers may pour boxes of food items (e.g., potatoes, apples) into the hopper 102, In some embodiments, the hopper 102 may be coupled to additional equipment. For example, the hopper 102 may be coupled to a tube (not shown) carrying food items. In another example, the hopper 102 may be coupled to harvesting equipment (e.g., conveyor on a potato harvester).

[011] From the hopper 102, food items may pass through chute 104. The food items may be transported through the chute 104 by gravity, forced air, and/or other transport mechanism (e.g., a conveyor). In some embodiments, transport of food items from the hopper 102 to the chute 104 may be controlled by a computer system, such as computer system 108. For example, a computer system 108 can be coupled to a conveyor (not shown), where signals from the computer system 108 may be received by the conveyor to adjust the speed of the conveyor such that the transport of food items from the hopper 102 to the chute 104 may be controlled. In some embodiments, hopper 102 may be omitted, and a conveyor may directly transport food items to the chute 104. The chute 104 may have a diameter suitable to allow the food items to pass through the chute 104 one at a time. In some embodiments, the diameter of the chute 104 may be adjustable.

The chute 104 may convey individual food items to the EIT sensor 106. For example, transport of food items from the chute 104 to the EIT sensor 106 may be controlled by a computer system that is coupled to the chute, where the operation of the chute is actuated responsive to signals received from the computer system. The EIT sensor 106 may include multiple electrodes. The EIT sensor 106 may apply one or more signals (e.g., voltages, currents) to a food item and measure a resulting signal or signals (e.g., currents, voltages, impedance) through the food item or at least a portion of the food item. The EIT sensor 106 may generate EIT signals based on the measured signals. In some embodiments, system for sorting food items 100 may include multiple EIT sensors 106.

The EIT sensor 106 may be coupled to the computer system 108 to provide EIT signals to the computer system 108, The computer system 108 may process the EIT signals to determine whether or not the food item is defective and/or determine a characteristic of the food item (e.g., moisture content, sugar content, size). In some embodiments, the computer system 108 may provide signals (e.g., control signals) to the EIT sensor 106. For example, the EIT sensor 106 may apply signals and/or measure resulting signals responsive to signals from the computer system 108,

The system for sorting food items 100 may optionally include additional sensors 107.

In some embodiments, some or all of the additional sensors 107 are included in a unit including the EIT sensor 106. In some embodiments, some or ail of the additional sensors 107 may be separate from the EIT sensor 106. Additional sensors 107 may include, but are not limited to temperature sensors, position sensors, and optical sensors (e.g., charged coupled device). The additional sensors 107 may also provide signals that may be used to determine whether or not the food item is defective and/or determine a characteristic of the food item. For example, an optical sensor may determine a color of a food item. In another example, a position sensor may determine a volume, diameter, length, and/or other dimension of a food item. The additional sensors 107 may provide additional sensor signals to the computer system 108 for processing.

[015] After characteristics of a food item have been measured by the EIT sensor 106 (and optional ly additional sensors 107), the food item may be routed by a sorting gate 1 10 into one of multiple outputs. The sorting gate 1 10 may be coupled to and controlled by the computer system 108 in some embodiments. Based on the determination of a defect and/or characteristic, the computer system 108 may provide a signal (e.g., a control signal) to the sorting gate 1 10. Based on the signal, the sorting gate may route the food item to an output.

[016] As shown in Figure 1 , the system for sorting food items 100 may have three outputs

1 12, 1 14, and 1 16. However, in some embodiments, the system for sorting food items 100 may have two outputs (e.g., acceptable and unacceptable) or more than three outputs. In the example shown in Figure 1, output 1 12 may be for food items suitable for a first production line, output 1 14 may be for food items unsuitable for the first production line but suitable for a second production line and/or other application, and output 1 16 may be for defective (e.g., moldy) food items. For example, some potatoes may have a suitable moisture content for frying into potato chips. These potatoes may be sorted to output 1 2. Other potatoes may be rotten and unsuitable for any production. These potatoes may be sorted to output 1 16. Final ly, the remaining potatoes may have a moisture content unsuitable for potato chips, but are not moldy or otherwise defective. These potatoes may be sorted into output 1 14, perhaps to be sold whole to consumers or used in another food production line (e.g., powdered mashed potatoes, French fries). This described configuration of output types is provided as an example, and the system for sorting food items 100 is not limited to these output types.

[017] Figure 2 is a schematic illustration of a system for sorting food items 200, arranged in accordance with at least some embodiments described herein. Figure 2 shows hopper 202, chute 204, EIT sensor 206, sorting gate 208, and outputs 210 and 212. The various components described in Figure 2 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[018] As shown in Figure 2, in some embodiments, the hopper 202 may have a conical or sloped portion that may couple to the chute 204 below. However, in some embodiments, the hopper 202 may be positioned next to the chute 204 rather than above the chute 204. The chute 204 may be made of a single member (e.g., tube, trough) or multiple members. In some embodiments, the chute 204 may include six or more vertical members that define a cylinder-shape. This example embodiment is shown in the example in Figure 2 in the longitudinal cross-section 205 of the chute 204.

[019] The chute 204 is positioned to effectively transport food items from the hopper 202 to the EIT sensor 206. The EIT sensor 206 may be located at the end of the chute 204 or at an intermediate location located along a path of the chute 204. As shown in the example in Figure 2, the EIT sensor 206 is located midway along the chute 204, In other words, individual food items may continue down the path of the chute 204 after passing through the EIT sensor 206 in some embodiments. As can be seen in the longitudinal cross-section 207, the EIT sensor 206 may include multiple portions (e.g., six). In some embodiments, the portions of the EIT sensor 206 may be electrodes. In some embodiments, the portions of the EIT sensor 206 may include electrode supports, which may include one or more electrodes. The portions of the EIT sensor 206 may be flexibly mounted to the chute 204 in some embodiments. For example, the portions may be pivotally mounted or spring mounted to a surface or edge of the chute 204. In some embodiments, the EIT sensor 206 may be a self- contained unit that is located downstream of the chute 204 (e.g., positioned in a location encountered by an individual food item after entering and/or exiting the chute 204). That is, the EIT sensor 206 may receive individual food items from the chute, but may not be physically coupled to the chute. For example, the EIT sensor 206 may be located at an end of the chute 204. In another example, the FIT sensor 206 may be spaced (e.g., 1 cm, 5 cm, 10 cm) from an end of the chute 204. ] Whether coupled to the chute 204 or an independent unit, the various portions of the HI I sensor 206 may be biased towards the individual food items (e.g., hinge, spring, flexible material), which may allow electrodes of the EIT sensor 206 to maintain contact with the food item during measurement of characteristics of the individual food items (e.g., voltage, current, temperature, etc.). In some embodiments, the EIT sensor 206 may have one or more mechanical actuators that move a portion or portions of the EIT sensor 206 into contact with individual food items. The mechanical actuators may be controlled by signals provided by a computer system (not shown in FIG. 2) in some embodiments, for example computer system 108 shown in FIG. 1. One or more of the electrodes of the EIT sensor 206 may apply a signal (e.g., current, voltage) through at least a portion of the food item, A second signal (e.g., current, impedance) resulting from the signal applied may be detected at the electrode and/or one or more of the other electrodes. Multiple signals may be applied and/or measured simultaneously (e.g., in a same time period) and/or in sequence by one or more electrodes of the EIT sensor 206 at different locations on the food item. Based on the measured signals, the EIT sensor 206 may generate sensor signals.

I Although various examples described herein refer to electrodes that apply current to food items to facilitate measurements made with FIT sensors, it is contemplated that any appropriate signal may be applied via electrodes, including but not limited to currents, voltages, and other electrical signals. In some examples, signals may be applied by the electrodes in a continuous manner as measurements are being made. In other examples, signals may be applied by the electrodes in a pulsed manner as measurements are being made. In still other examples, signals may be applied by the electrodes as a waveform (e.g., sine, ramp, saw tooth, linear, non-linear, or piecewise waveform etc.) as measurements are being made. In still further examples, signals may be applied by the electrodes in a complex manner, with a combination of continuous signals, pulsed signals, and/or any appropriate waveform(s).

] In some embodiments, the EIT sensor 206 may make characteristic measurements on every individual food item that passes through chute 204. In other embodiments, the EIT sensor 206 may make characteristic measurements on only select individual food items. That is, only a sample (e.g., 1%, 5%, 20%) of the individual food items may be measured by the EIT sensor 206. The sample size may be based on government regulations, industry standards, and/or user preference. Measurements by the EIT sensor 206 may take 1-10 seconds in some embodiments. Measurement times may be longer or shorter depending on factors such as electrode type, grade of electronic components, and/or type of food item being measured.

[023] Although not shown in FIG. 2, the system for sorting food items 200 may also include additional sensors, such as the additional sensors 107 described with reference to FIG. 1. The additional sensors may be included with EIT sensor 206 and/or located proximate to EIT sensor 206 along chute 204. The additional sensors may make characteristic measurements on the individual food items before, during, and/or after the EIT sensor 206 makes measurements. For example, a position sensor may be included with the EIT sensor 206. When the EIT sensor 206 moves to make contact with an individual food item, the position sensor may determine a dimension and/or volume of the individual food item based at least in part on the position of the EIT sensor 206. In some embodiments, the EIT sensor 206 may move responsive to signals from a computer system to actuators included with the EIT sensor 206. In some embodiments, the EIT sensor may move responsive to the individual food item applying force to a spring-loaded pivot pin included with the EIT sensor 206. In another example, a CCD camera may be mounted in chute 204 and may acquire images of individual food items. The images may be analyzed by a computer system to determine one or more characteristics of the individual food items (e.g., color, size, shape). In a further example, a thermal camera may be included with the EIT sensor 206 or mounted in chute 204 and may acquire a thermal image (e.g., heat map) of the individual food items. The thermal image may be acquired before, during, and/or after measurements are made with the EIT sensor 206.

[024] After the EIT sensor 206 has made measurements on the food item, it may pass down another portion of chute 204 as shown in Figure 2, or may pass directly to the sorting gate 208. In some embodiments, the sorting gate 208 may include one or more paddles that can pivot to different positions to selectively block one or more outputs. As shown in Figure 2, the paddl e of the sorting gate 208 i s blocking output 210. Thus, a food item passing through the EIT sensor 206 can be routed to output 212. In some embodiments, the sorting gate 208 may be a turntable that aligns a chute to a desired output with the EIT sensor 206. The sorting gate 208 may route food items to different outputs based, at least in part, on the current measured by the EIT sensor 206. In some embodiments, the sorting gate 208 may route food items directly responsive to the EIT sensor signals. In other embodiments, the sorting gate 208 may route food items responsive to signals provided by a computer system (not shown in Figure 2).

I The system for sorting food items 200 includes two outputs 210 and 212. One of the two outputs (e.g., 210) may be for suitable food items and the other output may be for defective and/or unsuitable food items. In some embodiments, the outputs 210 and 212 may include troughs, bins, and/or conveyors. For example, a first potato may be suitable for production and be routed by the sorting gate to output 210. Output 210 may lead to a bin for storing acceptable potatoes for washing. A second potato may be found to be defective (e.g., moldy). Output 212 may include a chute that dumps the second potato on the ground behind the system for sorting food items 200, and the second potato may be churned back into the ground for fertilizer by other equipment. This example is provided for illustrative purposes, and the outputs 210, 212 are not limited to this configuration. Furthermore, as mentioned earlier in reference to system for sorting food items 100, system for sorting food items 200 may include more than two outputs.

I Figure 3 is a schematic illustration of a portion 300 of an EIT sensor, arranged in accordance with at least some embodiments described herein. Figure 3 shows a side view 302, a front view 304, and an end view 306 of an electrode support 308 with a pivot pin 312, electrode 310, and optional additional sensor 307. The various components described in Figure 3 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

I The electrode support 308 may be implemented with metal, plastic, and/or a composite (e.g., fiber glass, carbon fiber). In some embodiments, such as the one shown in the front view 304 of Figure 3, the electrode support 308 may be trapezoidal shaped with a narrow portion at an end near the electrode 310 and a wide portion at another end opposite the electrode 310. The electrode support 308 may be implemented in a variety of shapes. For example, the electrode support 308 may be rectangular or ovular. As can be seen in the side view 302, the electrode support 308 may be substantially straight with a flat surface. However, in some examples the electrode support 308 may be curved and/or the surface that contacts food items may have a concave surface in some embodiments. In some embodiments, the surface or a portion of the surface in contact with food items may be textured and/or include a coating (e.g., rubber, silicon) that may improve contact with individual food items.

] The electrode support 308 may couple to a chute (e.g., chute 204 in Figure 2) or another portion of a system for sorting food items. The electrode support 308 may be coupled by pivot pin 312. The electrode support 308 may be configured to pivot around the pivot pin to conform with a surface of an individual food item. In some embodiments, the pivot pin 312 may be spring-loaded such that the electrode support 308 is biased towards the individual food items. In some embodiments, a spring (not shown) may be coupled between the electrode support 308 and another surface (e.g., a chute) to bias the electrode support 308.

] The electrode 310 may be located at a lower tip of the electrode support 308 as shown in Figure 3, However, the electrode 310 may be located anywhere on the surface of the electrode support 308 that contacts food items. In some embodiments, the electrode 310 may be one of a plurality of electrodes on the electrode support 308. In some embodiments, the electrode support 308 itself may be an electrode. In embodiments where the electrode support 308 itself is an electrode, the electrode may be spring-loaded such that the electrode is biased towards the individual food items. The electrode 310 may be implemented as a ball of conductive material (e.g., copper, gold, conductive polymer) in some embodiments. The electrode 310 may be implemented as a conductive film and/or plating in some embodiments. The electrode 3 0 may be configured to apply a signal (e.g., current) and/or measure a resulting signal through at least a portion of an individual food item. Based on the electrode 310 measurements, the EIT sensor may generate EIT sensor signals. ] Optionally, the electrode support 308 may include an additional sensor 307 (or sensors) in some embodiments. Additional sensor 307 may include, but are not limited to position sensors, temperature sensors, and optical sensors (e.g., CCD, thermal camera, photodiode). For example, in some embodiments, the pivot pin 312 may include a strain gauge. The strain gauge may act as a position sensor and/or a portion of a position sensor. In another example, additional sensor 307 may include a thermocouple that detects a temperature of an individual food item. In some embodiments, additional sensors may be included in another portion of the BIT sensor.

] Figure 4 is a block diagram of a portion of a system for sorting food items 400, arranged in accordance with at least some embodiments described herein. Figure 4 shows computer system 406, FIT sensor 402, sorting gate 404, and optional additional sensor 407. Computer system 406 may include a processing unit 408 and memory 410 that may include executable instructions for BIT analysis 412, BIT reference data 414, optional executable instructions for additional sensor analysis 415, and additional sensor reference data 16. The various components described in Figure 4 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

] Computer system 406 may be used to implement computer system 108 shown in

Figure 1. BIT sensor 402 may be implemented with BIT sensor 106 or BIT sensor 206 and sorting gate 404 may be implemented with sorting gate 110 or sorting gate 208 in some embodiments. In some embodiments, the computer system 406 may be configured to receive an BIT signal from the BIT sensor 402, The BIT signal may be indicative of a signal (e.g., current, impedance, voltage) measured by the EIT sensor 402 through at least a portion of a food item. The signal may have been measured at one or more locations of the food item. The computer system 406 may receive one or more EIT signals from the EIT sensor 402. The BIT signal may be received continuously, periodically (e.g., pulsed, sampled), or non- periodicaliy (e.g., intermittently, when an individual food item is detected in the EIT sensor, when desired by a user). Based at least in part on the EIT signal, the computer system 406 may provide a signal to the sorting gate 404 to select an output to route the food item to. Responsive to the signal, the sorting gate 404 may route the food item to the selected one of multiple outputs (not shown in Figure 4). For example, the computer system 406 may provide a first signal to route the food item to a first output if the food item is determined to have a defect and a second signal to route the food item to a second output if the food item is determined to be defect-free.

[033] In some embodiments, the processing unit 408 included in the computer system 406 may execute the executable instructions for EIT analysis 412 stored in memory 410. The processing unit 408 may perform other tasks such as generating signals to send to the sorting gate 404 in some embodiments. The processing unit 408 may be implemented with one or more processors.

[034] The executable instructions for EIT analysis 412 may include instructions to compare the received EIT signal with the EIT reference data 414 stored in memory in some embodiments. The comparison of the received EIT signal and the EIT reference data 414 may be used to determine whether or not the food item has a defect or to determine another characteristic of the food item (e.g., moisture content). The control signal generated by the computer system 406 to route the food item to a particular output may be based, at least in part, on this characteristic determination. In some embodiments, the computer system 406 may determine whether or not the food item has a defect or determine another characteristic of the food item without comparing the EIT signal to the EIT reference data 414.

[035] The EIT reference data 414 may include one or more sets of EIT measurements from one or more food items in some embodiments. For example, the EIT reference data 414 may include sets of measurements from food items known to have a certain moisture content and/or known to have one or more defects. In some embodiments, the EIT reference data 414 may include one or more threshold values (e.g., current voltage, impedance). For example, an EIT signal indicative of a value above or below a threshold value may be indicative of a defect. In another example, an EIT signal indicative of a value between two threshold values may be indicative of a particular moisture content.

[036] In some embodiments, the computer system 406 may receive EIT signals from multiple EIT sensors 402, For example, a system for sorting food items may include multiple EIT sensors 402 to test an individual food item. In another example, a system for sorting food items may measure multiple individual food items at once. This may allow for parallel processing of food items. Similarly, the computer system 406 may provide signals to multiple sorting gates 404. Multiple sorting gates 404 may be used when there are multiple outputs and/or when individual food items are being sorted in parallel.

] In some embodiments, the computer system 406 may optionally be configured to receive an additional sensor signal from the additional sensor 407, Based at least in part on the additional sensor signal and/or combination of the additional sensor signal and EIT signal, the computer system 406 may provide a signal to the sorting gate 404 to select an output to route the food item to the selected one of multiple outputs. In some embodiments, the processing unit 408 may execute the executable instructions for additional sensor analysis 415 stored in memory 410. In some embodiments, the memory 410 may further include additional sensor reference data 416, which may be used by the computer system 406 to determine whether or not the food item has a defect or to determine another characteristic of the food item.

] Figure 5 is a flowchart of an example method 500 according to at least some of the embodiments described herein. An example method may include one or more operations, functions or actions as illustrated by one or more of blocks 502, 504, 506, 508 and/or 510. The operations described in the blocks 502 through 510 may be performed in response to execution (such as by one or more processors described herein, for example, processing unit 408 in Figure 4) of computer-executable instructions stored in a computer-readable medium, such as a computer-readable medium of a computer device or some other controller similarly configured.

] An example process may begin with block 502, which recites "Transport food item from hopper into contact with EIT sensor." Block 502 may be followed by block 504, which recites "Apply a signal to food item and measure a resulting signal through food item." Block 504 may be followed by block 506, which recites "Compare EIT sensor signal with reference data to provide defect signal." Block 506 may be followed by block 508, which recites, "Determine moisture content of food item." Block 508 may be followed by block 510, which recites, "Route food item to selected output."

i\ The blocks included in the described example methods are for illustration purposes.

In some embodiments, the blocks may be performed in a different order. In some other embodiments, various blocks may be eliminated. In still other embodiments, various blocks may be divided into additional blocks, supplemented with other blocks, or combined together into fewer blocks. Other variations of these specific blocks are contemplated, including changes in the order of the blocks, changes in the content of the blocks being split or combined into other blocks, etc. In some examples, block 506 and/or block 508 may be omitted.

L] Block 502 recites, "Transport food item from hopper into contact with HI I sensor."

The food item may be transported from a hopper (e.g., hopper 102, hopper 202) to contact an EIT sensor through a chute (e.g., chute 104, chute 204) in some embodiments. The food item may be transported via gravity, a conveyor, water stream, and/or a pneumatic system. In some embodiments, the food item may be brought into contact with one or more electrodes included with the EIT sensor. The one or more electrodes may be arranged around a circumference of a chute. The one or more electrodes may conform to a surface of the food item.

t] Block 504 recites, "Apply a signal to food item and measure a resulting signal through food item." The signal may be applied by one or more EIT sensors that include one or more electrodes in contact with the food item. One or more signals may be applied by one or more electrodes at the same time or in sequence. The resulting signal or signals may be measured by one or more electrodes. In some embodiments, signals may be applied by the electrodes in a continuous manner as measurements are being made. In other embodiments, signals may be applied by the electrodes in a pulsed manner as measurements are being made. In still other examples, signals may be applied by the electrodes as a waveform (e.g., sine, ramp, saw tooth, linear, non-linear, or piecewise waveform etc. ) as measurements are being made. In still further embodiments, signals may be applied by the electrodes in a complex manner, with a combination of continuous signals, pulsed signals, and/or any appropriate waveforrn(s). For example, an electrode may apply a voltage to a food item and one or more other electrodes may measure a current through at least a portion of the food item. The current through the food item may be indicati ve of a characteristic of the food item, such moisture content. In another example, an electrode may apply a current to a food item and the electrode and/or one or more electrodes may measure an impedance of the food item. The impedance of the food item may be indicative of a defect in the food item such as internal rot,

[043] Block 506 recites, "Compare EIT sensor signal with reference data to provide defect signal." The EIT sensor may generate an EIT sensor signal indicative of the resulting signal or signals measured through the individual food item. The EIT sensor signal may be compared to reference data. In some embodiments, the EIT sensor signal may be received by a computer system (e.g., computer system 406), The computer system may analyze the EIT sensor signal. The computer system may include a memory that contains reference data to compare to the received EIT sensor signal. Based on the comparison of the EIT sensor signal with the reference data, the computer system may generate a defect signal indicative of whether or not the food item has a defect. In some embodiments, the EIT sensor may generate a defect signal based on the measured resulting signal rather than a computer system. In some embodiments, block 506 or a portion of 506 may be omitted. For example, a system for sorting food items may be configured to determine characteristics of food, not to determine whether or not food items are defective. In another example, the computer system may generate a defect signal based on a calculation or threshold value rather than reference data,

[044] Block 508 recites, "Determine moisture content of food item." In some embodiments, the EIT sensor signal may be received by a computer device. The computer system may determine the moisture content of the food item based at least in part on the EIT sensor signal. In some embodiments, block 508 may be omitted. For example, a system for sorting food items may be configured to determine whether or not food items have defects, not determine specific characteristics of food items. [045] Block 510 recites, "Route food item to selected output." The food item may be routed based on the EIT sensor signals. In some embodiments, the routing of the individual food item is based on a defect signal generated by the EIT sensor and/or computer system. In some embodiments, the routing of the food item is based on the determined moisture content of the food item. Routing the food item to the selected output may involve controlling a sorting gate to open a path to the selected output. The sorting gate may be controlled responsive to a signal based on the EIT sensor signal. In some embodiments, the computer system may generate the signal and provide the signal to the sorting gate.

[046] After the individual food item has been routed to the selected output, the next food item may be transported to the EIT sensor. The next food item may be processed according to blocks 502-510 of method 500. In some embodiments, method 500 may be repeated until all food items in the hopper have been sorted.

[047] Figure 6 is a block diagram illustrating an example computer device 600 that is arranged for sorting food items in accordance with the present disclosure. In some embodiments, computer device 600 may be used to implement computer system 406 shown in Figure 4. In a very basic configuration 601, computer device 600 typically includes one or more processors 610 and system memory 620. A memory bus 630 may be used for communicating between the processor 610 and the system memory 620.

[048] Depending on the desired configuration, processor 610 may be of any type including but not limited to a microprocessor (μΡ), a microcontroller (μθ), a digital signal processor (DSP), or any combination thereof. In some embodiments, processor 610 may be used to implement processing unit 408. Processor 610 may include one or more levels of caching, such as a level one cache 611 and a level two cache 612, a processor core 613, and registers 614. An example processor core 613 may include an arithmetic logic unit (ALU), a floating point unit (FPU), a digital signal processing core (DSP Core), or any combination thereof. An example memory controller 615 may also be used with the processor 610, or in some implementations, the memory controller 615 may be an internal part of the processor 610.

[049] Depending on the desired configuration, the system memory 620 may be of any type including but not limited to volatile memory (such as RAM), non-volatile memory (such as ROM, flash memory, etc.) or any combination thereof. System memory 620 may include an operating system 621, one or more applications 622, and program data 624. Application 622 may include an FIT analysis procedure 623 (e.g., executable instructions for EIT analysis 412 shown in Figure 4) that is arranged to determine the presence of food defects and/or determine characteristics of food items as described herein. Program data 624 may include EIT reference data 625 (e.g., EIT reference data 414), and/or other information useful for the implementation of EIT analysis. In some embodiments, application 622 may be arranged to operate with program data 624 on an operating system 621 such that any of the procedures described herein may be performed. This described basic configuration is illustrated in FIG. 6 by those components within dashed line of the basic configuration 601.

[050] Computer device 600 may have additional features or functionality, and additional interfaces to facilitate communications between the basic configuration 601 and any required devices and interfaces. For example, a bus/interface controller 640 may be used to facilitate communications between the basic configuration 601 and one or more storage devices 650 via a storage interface bus 641 . The storage devices 650 may be removable storage devices 651, non-removable storage devices 652, or a combination thereof. Examples of removable storage and non-removable storage devices include magnetic disk devices such as flexible disk drives and hard-disk drives (HDD), optical disk drives such as compact disk (CD) drives or digital versatile disk (DVD) drives, solid state drives (SSD), and tape drives to name a few. Example computer storage media may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data.

[051] System memory 620, removable storage 651 and non-removable storage 652 are all examples of computer storage media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which may be used to store the desired information and which may be accessed by computer device 600. Any such computer storage media may be part of computer device 600. [052] Computer device 600 may also include an interface bus 642 for facilitating communication from various interface devices (e.g., output interfaces, peripheral interfaces, and communication interfaces) to the basic configuration 601 via the bus/interface controller 640. Example output devices 660 include a graphics processing unit 661 and an audio processing unit 662, which may be configured to communicate to various external devices such as a display or speakers via one or more A/V ports 663, Example peripheral interfaces 670 include a serial interface controller 671 or a parallel interface controller 672, which may be configured to communicate with external devices such as input devices (e.g., keyboard, mouse, pen, voice input device, touch input device, etc.) or other peripheral devices (e.g., printer, scanner, etc.) via one or more 170 ports 673. An example communication device 680 includes a network controller 681, which may be arranged to facilitate communications with one or more other computer devices 690 over a network communication link via one or more com muni cation ports 682.

[053] The network communication link may be one example of a communication media.

Communication media may typically be embodied by computer readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and may include any information delivery media. A "modulated data signal" may be a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, and not limitation, communication media may include wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency (RF), microwave, infrared (IR) and other wireless media. The term computer readable media as used herein may include both storage media and communication media.

[054] Computer device 600 may be implemented as a portion of a small-form factor portable (or mobile) electronic device such as a cell phone, a personal data assistant (PDA), a personal media player device, a wireless web-watch device, a personal headset device, an application specific device, or a hybrid device that include any of the above functions. Computer device 600 may also be implemented as a personal computer including both laptop computer and non-laptop computer configurations. [055] Figure 7 is a block diagram illustrating an example computer program product 700 that is arranged to store instructions for sorting food items in accordance with the present disclosure. The signal bearing medium 702 which may be implemented as or include a computer-readable medium 706, a recordable medium 708, a communications medium 710, or combinations thereof, stores programming instructions 704 that may configure a processing unit (e.g., processing unit 408) to perform all or some of the processes previously described. These instructions may include, for example, one or more executable instmctions for causing transport an individual food item from a hopper into contact with an electrical impedance tomography sensor, apply voltages to the individual food item using the EIT sensor and measuring currents through the individual food item using the EIT sensor to provide EIT sensor signals, and route the individual food item to a selected output based on the EIT sensor signals. Although the example in FIG. 7 provides for applying voltages to a food item and measuring a current, it is understood that a computer program product could include executable instructions for applying and measuring other signals or a combination of signals through an individual food item. Other signals include, but are not limited to, alternating current, direct current, impedance, and light (e.g., infrared).

[056] The systems and methods described herein may be used with various food items, such as potatoes. However, the systems and methods may be used with other food items including but not limited to yams, apples, and grapefruits. The systems and methods described herein may allow for food items to be sorted at or near a harvest site and/or receiving site. Sorting food items as described herein may allow defective or otherwise unsuitable food items to be separated out, and washing and transportation costs for these food items may be avoided.

[057] The present disclosure i s not to be limited in terms of the arti cular examples described in this application, which are intended as illustrations of various aspects. Many modifications and examples can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and examples are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds compositions or biological systems, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting.

] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art. can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.).

] It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to examples containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should be interpreted to mean "at least one" or "one or more"), the same holds true for the use of defi nite arti cles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations).

[061] Furthermore, in those instances where a convention analogous to "at least one of A,

B, and C, etc." is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibi lities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or " A and B "

[062] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[063] As will be understood by one skilled in the art, for any and ail purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as "up to," "at least," "greater than," "less than," and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 items refers to groups having 1 , 2, or 3 items. Similarly, a group having 1-5 items refers to groups having 1, 2, 3, 4, or 5 items, and so forth.

[064] While the foregoing detailed description has set forth various examples of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples, such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one example, several portions of the subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), Digital Signal Processors (DSPs), or other integrated formats. However, those skilled in the art will recognize that some aspects of the examples disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and/or firmware would be well within the skill of one of skill in the art in light of this disclosure. For example, if a user determines that speed and accuracy are paramount, the user may opt for a mainly hardware and/or firmware vehicle, if flexibility is paramount, the user may opt for a mainly software implementation; or, yet again alternatively, the user may opt for some combination of hardware, software, and/or firmware.

[065] In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative example of the subject matter described herein applies regardless of the particular type of signal bearing medium used to actually carry out the distribution. Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a Hard Disk Drive (HDD), a Compact Disc (CD), a Digital Video Disk (DVD), a digital tape, a computer memory, etc.; and a transmission type medium such as a digital and/or an analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communication link, a wireless communication link, etc.).

[066] Those skilled in the art will recognize that it is common within the art to describe devices ami/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes into data processing systems. That is, at least a portion of the devices and/or processes described herein can be integrated into a data processing system via a reasonable amount of experimentation. Those having skill in the art will recognize that a typical data processing system generally includes one or more of a system unit housing, a video display device, a memory such as volatile and nonvolatile memory, processors such as microprocessors and digital signal processors, computational entities such as operating systems, drivers, graphical user interfaces, and applications programs, one or more interaction devices, such as a touch pad or screen, and/or control systems including feedback loops and control motors (e.g., feedback for sensing position and/or velocity; control motors for moving and/or adjusting components and/or quantities). A typical data processing system may be implemented utilizing any suitable commercially available components, such as those typically found in data computing/communication and/or network computing/communication systems.

[067] The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected", or "operably coupled", to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable", to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.

While various aspects and examples have been disclosed herein, other aspects and examples will be apparent to those skilled in the art. The various aspects and examples disclosed herein are for puiposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.