Patent ID: 12225861

DESCRIPTION

Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

One aspect of the invention provides a method of delivering light (e.g. photosynthetically active photons) to a plurality of plants within a grow room of an indoor farming operation while maintaining a desired temperature range within (and throughout) the grow room.

FIG.1depicts an exemplary method100of delivering light (e.g. photosynthetically active photons) to a plurality of plants within a grow room according to one embodiment of the invention. For the purpose of illustrating method100, an exemplary non-limiting grow room10is described herein.

FIGS.2and3depict an exemplary non-limiting grow room10. It should be understood that grow room10is presented for illustrative purposes. The description and drawings of grow room10provided herein are not intended to limit any aspects of a grow room for which method100may be employed. For example, the description and drawings herein are not intended to limit the grow room size, grow room shape, arrangement of racks within the grow room, arrangement of lights within the grow room, arrangement of plants within the grow room, choice of plant varietal within the grow room, etc.

As shown inFIGS.2and3, a plurality of plants20are arranged on racks30within grow room10. Racks30may be spaced apart horizontally (e.g. in the x-direction and/or y-direction). Lights40may be arranged to provide photons to each plant20. Each light40may provide light to one or more plants20.

Racks30may comprise any suitable racks. Each rack30may provide multiple rows32of plants20and lights40. This is not mandatory. Rows32may be stacked in the z-direction (e.g. vertically or substantially vertically) as shown inFIG.3. In the illustrated embodiment, each rack30comprises four rows32(e.g. rows32-1,32-2,32-3,32-4). This is not mandatory. Each rack30may comprise any number of rows32.

Plants20may comprise any suitable plants. Plants20may comprise plants of a single varietal or of multiple varietals. For example, plants20may comprise leafy greens (e.g. lettuce, spinach, kale, Swiss chard, etc.), spices (e.g. saffron, vanilla, mustard, etc.), herbs, microgreens, vegetables (e.g. mushrooms, eggplants, squash, peppers, cucumbers, etc.), fruit (e.g. berries, tomatoes, etc.), grains (rice, wheat, corn, barley, oat, sorghum, rye, quinoa etc.), cannabis, medicinal plants, sprouts, pumpkins, etc. Plants20may comprise another plant varietal suitable for indoor farming. Plants may have nutrients delivered via different techniques (e.g. hydroponics, aquaponics, aeroponics, etc.). Plants20may be grown in a substrate medium that could be natural or synthetic (e.g. soil, rock wool, peat moss, coconut coir, perlite, vermiculite, clay pebbles, rock lava, rocks, polymer-based mediums, etc.).

Lights40may comprise any suitable lights which produce photosynthetically active photons. Lights40may comprise full spectrum lights. Lights40may comprise LED lights. When lights40are turned on, lights40may produce heat. The heat output of lights40may be approximately proportionate to the intensity of the light output of lights40.

In the illustrated embodiments, two lights40are provided for each plant20. This not mandatory. A greater or lesser number of lights40per plant20may be provided. Each light40may correspond to one or more plants20and each plant20may correspond to one or more lights40. In other words, one light40may provide photons to a plurality of plants and/or each plant may receive photons from a plurality of lights.

To better control which lights40deliver photons to which plants20, one or more dividers, walls, curtains or the like may be provided. For example, one or more dividers, walls, curtains or the like may be provided between racks30to prevent lights40on a first rack30from undesirably providing photons to plants20on a second rack30. Similarly, one or more dividers, walls, curtains or the like may be provided between rows32to prevent lights40on a first row32from undesirably providing photons to plants20on a second row32. Such dividers, walls, curtains or the like could even be provided within rows32to separate plants20and lights40within a row32.

Grow room10may be enclosed so as to prevent natural light or other exterior light from entering grow room10. The walls, windows and/or ceiling of grow room10may be covered at least in part in a reflective material such as panda film and/or insulating elements (e.g. insulation panels).

Returning toFIG.1, method100comprises a first step110of obtaining or determining the desired total light integral (“TLI”) for each plant20within grow room10. Like DLI, TLI may be used to understand and evaluate the quantity of light a plant is receiving. Like DLI, TLI is a cumulative measure of photosynthetically active radiation (“PAR”). TLI may be defined as the quantity of photosynthetically active photons received by plants per area for a given time period. Unlike, DLI which is limited to a 24 hour time period, the TLI may provide a measure of the quantity of light received by plants per area for a time period other than 24 hours. However, where the time period is 24 hours, the TLI would be equal to the DLI. The TLI may be determined based at least in part on the DLI. The DLI and/or TLI for each plant20may be obtained at step110by any suitable method. For example, the DLI and/or TLI may be obtained through pre-existing sources of such information or through experimentation. In some embodiments, the PPFD and/or photoperiod may also be obtained or determined at step110.

In some embodiments, the DLI for each plant20within grow room10will be the same or similar (e.g. each plant20with grow room10will be of the same varietal or varietals having the same or similar DLI and/or TLI), but this is not mandatory. Different plant varietals having different DLIs, TLIs, photoperiods and/or PPFDs may be provided within grow room10and/or different plant varietals having the same or similar DLIs, TLIs, photoperiods and/or PPFDs may be provided within grow room10.

At step120, each plant20is separated into a group50. While plants20in a group50may be physically separated from plants20in other groups50, this is not mandatory. Instead, plants20may be nominally separated into groups50such that plants20from one group50may be spread out in the x, y and/or z-directions within grow room10and/or separated from each other by plants20of other groups50.

The plants20of each group50may be chosen to achieve the following characteristics:each plant20in a group50has the same (or similar) photoperiod; andthe sum of the PPFD for all plants20in a group50is the same (or similar) for all groups50.

To achieve the above-noted characteristics of each group50, plants20may be separated into groups50based on a number of factors. For example, each plant20may be separated into groups50based on one or more of:the plant's DLI;the plant's TLI;the plant's photoperiod;the plant's PPFD;the plant's varietal;the plant's location within grow room10;the total number of plants20within grow room10;etc.

Groups50may be chosen such that plants20within a group50each have a photoperiod within 20% of each other, 10% of each other, 5% of each other or less. In this way, if all plants20within each group50are provided with light at the same time, no plant in group50will receive too many or too few hours of light.

Groups50may be chosen such that plants20within a group50each have a PPFD within 20% of each other, 10% of each other, 5% of each other or less. In this way, if all plants20within each group50are provided with the same intensity of light, no plant in group50will receive light that is too intense or not intense enough.

By arranging groups50such that the sum of the PPFD for all plants20in a group50is the same (or similar) for all groups50, energy consumption (e.g. to power lights) and heat output (e.g. from the lights) for each group50may be approximately consistent. This maintenance of approximately consistent light (and heat) output all day may reduce temperature fluctuations within grow room10and reduce overall energy consumption. For example, by reducing temperature fluctuations within grow room10due to heat generated from lights40, the usage of heating and cooling may be reduced thereby reducing energy usage and even capital costs necessary to build grow room10. Further, by maintaining more consistent temperatures within grow room10, less energy may be required for maintaining a desired humidity within grow room10. This effect may be rather substantial since more energy is required to remove moisture from cool air than from warm air and therefore avoiding coldspots or colder periods of time may be particularly advantageous.

Groups50may be chosen such that plants20within a group50each have a DLI within 20% of each other, 10% of each other, 5% of each other or less. Groups50may be chosen such that plants20within a group50each have a TLI within 20% of each other, 10% of each other, 5% of each other or less. In this way, if all plants20within each group50are provided with the same quantity of light, no plant in group50will receive too much or too little light.

To simplify achieving the above-noted characteristics of each group50, each group50could comprise an approximately equal number of plants20of a single varietal. This is not mandatory. Instead, groups50could be arranged with multiple varietals of plants20and different numbers of plants20. The number, N, of plants20in each group50may be any suitable number. In some embodiments, the number, N, of plants in each group50is chosen to achieve groups50with approximately equal rates of heat output during the photoperiod of the plant (e.g. with approximately equal sums of the PPFD for all plants20in a group50). For example, if plants20of a first group50of plants20each benefit from a relatively lower PPFD (with relatively lower heat output per light40) as compared to plants20of a second group50, then the first group50may be chosen to have a greater number, N, of plants20as compared to the second group50to achieve similar cumulative rates of heat output per group50. Put differently, if the PPFD of each plant20of the first group50is represented by a1and the PPFD of each plant20of the second group50is represented by a2where the first group has N1plants20and the second group has N2plants20, then the number, N1, of plants20in the first group20may be determined approximately as follows:

N1≈a2⁢N2a1

At step120, plants20may be separated into any number, n, of groups50. In some embodiments, the number, n, of groups50is based at least in part on the photoperiod(s) of plants20. In some embodiments, the sum of the photoperiods of all groups50is approximately equal to or greater than a time period, t. For practical reasons, the time period, t, may be 24 hours but this is not mandatory. For example, if the photoperiod of plants20in each group50is six hours, it may be desirable for the number, n, of groups50to be a multiple of four. With four groups and a photoperiod of six hours, each group50may be provided with its DLI in series in a 24 hour period.

In some embodiments, plants20in each group50are spread throughout grow room10in the x, y and/or z-directions. Spreading plants20of a group50around grow room10may facilitate even heat output of lights40around grow room10. As compared to arranging plants20of a group50together, spreading plants20of a group50throughout grow room10may reduce undesirable hot spots (e.g. where there is a greater concentration of lights40operating at a specific time in one area of grow room10than in other areas) and/or cool spots (e.g. where there is a lesser concentration of lights40operating at a specific time in one area of grow room10than in other areas).

Plants20in each group50may be spread out by alternating racks30and/or rows32within racks30into different groups50. For example, every second rack30could be a in a first group50while every remaining rack30is in a second group50. As another example, every second row32of every rack30may be in a first group50while the remaining rows32are in a second group50.

To facilitate spreading plants20within a group50throughout grow room10, grow room10may be nominally separated into sections12. In theFIG.2embodiment, room10is nominally separated into four sections12(section A, section B, section C and section D), each having four racks30. It should be understood that a grow room10may be nominally separated into any number of sections12, each having one or more racks30or portions of racks30. While sections12are depicted as being rectangular, this is not mandatory and sections12may be of any shape. The number, size and shape of sections12may be dependent on the size and/or shape of grow room10and/or the size, shape and/or number of racks30.

While sections12are depicted as including entire racks30, this is not mandatory. Instead, a first portion of a rack30may be part of a first section12while a second part of a rack may be part of a second section12. For example, a section12could include the first rows32-1of some or all of the racks30in a grow room10or a section12could include all of the even number rows32-2,32-4, etc. of some or all of the racks30in a grow room10. Similarly, while sections12are depicted and/or described as including entire rows32of racks30, this is not mandatory. Instead, different portions of rows could be part of different section12. For example, a first portion of a row32may be part of a first section12while a second portion of a row32may be part of a second section12.

To achieve a desired spread of plants20in each group50throughout grow room10, plants20may be picked from each section12. For example, each group50may comprise an equal or approximately equal number of plants20from each section12.

A similar principle may be applied to achieve a desired spread of plants20in each group50at different heights. For example, each group20may have at least one plant at every row32height or in alternating rows heights.

At step130, the desired TLI is provided to each plant20over the course of a time period, t, by sequentially providing light to each group50. The desired TLI for each plant is provided sequentially on a group-by-group basis. In some embodiments, light is provided sequentially to each group of plants50in a sequence that maintains the sum of PPFD in grow room10approximately constant throughout time period, t. Time period, t, may be a 24 hour time period but this is not mandatory. In some embodiments, lights40of only a single group50is on at any given time during time period, t, such that the sum of the PPFD in grow room10for any given time during time period, t, is approximately consistent. In other embodiments, lights40for multiple groups may be on at the same time. In such cases, the photoperiod for a first group50may overlap (in part or in whole) with the photoperiod of one or more other groups50. Where the photoperiods of groups50overlap, the sequence may be chosen such that the sum of the PPFD in grow room10for any given time during time period, t, is approximately consistent by maintaining consistent overlap between groups50receiving light. For example, if two groups50overlap at a given time during time period, t, then the sequence may be arranged such that two groups50substantially always (e.g. except for brief periods between photoperiods or otherwise) overlap during time period, t.

The schedule for sequentially providing light to groups20may be determined based on a number of factors to achieve an approximately constant cumulative heat output throughout time period, t (e.g. by maintaining an approximately constant sum of PPFD within grow room10throughout time period, t). In some embodiments, the total time of the photoperiods of groups50is approximately equal to the time period, t. In such embodiments, lights40for each group may be turned on sequentially for their corresponding photoperiod in series. In some embodiments, the total time of the photoperiods of groups50is less than the time period, t. In such cases, there may be short periods of time with no lights on. These short periods of time with no lights on may be spaced apart during time period, t, to reduce the effect of such time periods on the temperature within grow room10. An alternate heat source may be turned on (or turned up) during these short periods of time with no lights on. In some embodiments, where an alternative heat source is also used while the lights are on, the heat output of the alternative heat source may be increased during these short periods of time with no lights on (relative to when the lights are on). In some embodiments, the total time of the photoperiods of groups50is greater than the time period, t. In such cases, there may be overlap (in whole or in part) of photoperiods of different groups50.

In some embodiments, rather than provide lights40that are turned on for some periods of time and turned off for other periods of time, a smaller number of lights40that are always turned on (or turned on most of the time) is employed by moving lights40from group50to group50and/or moving groups50to lights40. By moving lights40and/or plants20, the same number of lights40may be turned on at all times which may result in a approximately constant rate of heat output from lights40.

Plants20may be placed on a conveyor system (e.g. a conveyor belt, a hanging conveyor, a water-based conveyor or the like). Plants20in a group50may then be moved under lights40to achieve the desired TLI and then moved away from lights40when the desired TLI is achieved to make way for another group50of plants20. The achieved TLI of plants20may therefore be controlled by the speed or interval at which they are moved under lights40, the intensity of lights40, etc.

Lights40may be placed on a conveyor system (e.g. a hanging conveyor or the like). Lights40may then be moved over a group50of plants20to achieve the desired TLI and then moved away from that group50when the desired TLI is achieved. Lights40may then be moved over another group50of plants20. The achieved TLI of plants20may therefore be controlled by the speed or interval at which lights40are moved, the intensity of lights40, etc.

In some embodiments, both lights40and plants20are arranged to be moveable to facilitate providing the desired TLI to plants20.

To better illustrate method100, a series of exemplary scenarios for grow room10are provided. These scenarios are meant to be illustrative only and are not intended to limit method100in any way. For the purpose of simplifying the following scenarios, it may be assumed that each row32of each rack30comprises the same number of plants20and the same number of lights40. However, it should be understood that in practice, each row32may have different numbers of plants20and/or lights40. Moreover, while the following scenarios are based on grow room10forFIGS.2and3, it should be understood that the scenarios could be modified for different grow rooms10described herein or otherwise. Further, while each of the following scenarios rely on turning lights40on and off, it should be understood that lights40and/or plants20could be moveable to avoid turning lights on and off.

Exemplary Scenario 1

In a first exemplary scenario, all plants20have a same or similar TLI and have a photoperiod of 12 hours. Plants20are nominally separated into a first group comprising all of plants20within racks A1, A3, B1, B3, C1, C3, D1and D3and a second group comprising all of plants20within racks A2, A4, B2, B4, C2, C4, D2and D4. In this way, there is an approximately equal number of plants20of each group50in each section12and at each row height.

A time period, t, of 24 hours is separated into a first sub-period of 12 hours and a second sub-period of 12 hours. During the first sub-period, lights40for the first group of plants20are turned on while lights40for the second group of plants20are turned off. During the second sub-period, lights40for the second group of plants20are turned on while lights40for the first group of plants20are turned off.

In the first exemplary scenario, the same number of lights40are turned on with the same intensity at all times during time period, t. Moreover, since plants20of each of the first and second groups50are spread apart around grow room10(in the x, y and z-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Exemplary Scenario 2

In a second exemplary scenario, all plants20have a same or similar TLI and have a photoperiod of 12 hours. Plants20are nominally separated into a first group comprising all of plants20within even-numbered rows of racks (e.g. all plants on rows32-2and32-4in grow room10) and a second group comprising all of plants20within odd-numbered rows racks (e.g. all plants on rows32-1and32-3in grow room10). In this way, there is an approximately equal number of plants20of each group50in each section12and at each row height.

A time period, t, of 24 hours is separated into a first sub-period of 12 hours and a second sub-period of 12 hours. During the first sub-period, lights40for the first group of plants20are turned on while lights40for the second group of plants20are turned off. During the second sub-period, lights40for the second group of plants20are turned on while lights40for the first group of plants20are turned off.

In the second exemplary scenario, the same number of lights40are turned on with the same intensity at all times during time period, t. Moreover, since plants20of each of the first and second groups50are spread apart around grow room10(in the x, y and z-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Exemplary Scenario 3

In a third exemplary scenario, all plants20have a same or similar TLI and have a photoperiod of 6 hours. Plants20are nominally separated into a first group comprising all plants20on rows32-1and32-3of racks A1, A3, B1, B3, C1, C3, D1and D3, a second group comprising all plants20on rows32-2and32-4of racks A1, A3, B1, B3, C1, C3, D1and D3, a third group comprising all plants20on rows32-1and32-3of racks A2, A4, B2, B4, C2, C4, D2and D4and a fourth group comprising all plants20on rows32-2and32-4of racks A2, A4, B2, B4, C2, C4, D2and D4. In this way, there is an approximately equal number of plants20of each group50in each section12and at each row height.

A time period, t, of 24 hours is separated into a first sub-period of 6 hours, a second sub-period of 6 hours, a third sub-period of 6 hours and a fourth sub-period of 6 hours. During the first sub-period, lights40for the first group of plants20are turned on while lights40for the second, third and fourth groups of plants20are turned off. During the second sub-period, lights40for the second group of plants20are turned on while lights40for the first, third and fourth groups of plants20are turned off. During the third sub-period, lights40for the third group of plants20are turned on while lights40for the first, second and fourth groups of plants20are turned off. During the fourth sub-period, lights40for the fourth group of plants20are turned on while lights40for the first, second and third groups of plants20are turned off.

As in the first exemplary scenario, the same number of lights40are turned on with the same intensity at all times during time period, t. Moreover, since plants20of each of the first, second, third and fourth groups50are spread apart around grow room10(in the x, y and z-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Exemplary Scenario 4

In a fourth exemplary scenario, all plants20have a same or similar TLI and have a photoperiod of 12 hours. Plants20are nominally separated into a first group comprising all plants20on rows32-1of all racks in grow room10, a second group comprising a all plants20on rows32-2of all racks in grow room10, a third group comprising all plants20on rows32-3of all racks in grow room10and a fourth group comprising all plants20on rows32-4of all racks in grow room10. In this way, there is an approximately equal number of plants20of each group50in each section12.

A time period, t, of 24 hours is separated into a first sub-period of 6 hours, a second sub-period of 6 hours, a third sub-period of 6 hours and a fourth sub-period of 6 hours. During the first sub-period, lights40for the first and fourth groups of plants20are turned on while lights40for the second, and third groups of plants20are turned off. During the second sub-period, lights40for the first and second groups of plants20are turned on while lights40for the third and fourth groups of plants20are turned off. During the third sub-period, lights40for the second and third groups of plants20are turned on while lights40for the first and fourth groups of plants20are turned off. During the fourth sub-period, lights40for the third and fourth groups of plants20are turned on while lights40for the first and second groups of plants20are turned off.

As in the first exemplary scenario, the same number of lights40are turned on with the same intensity at all times during time period, t. Moreover, since plants20of each of the first, second, third and fourth groups50are spread apart around grow room10(in the x and y-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Exemplary Scenario 5

In a fifth exemplary scenario, plants20are of two different varietals. The TLI for each plant is approximately equal but the first plant varietal has a photoperiod of 12 hours and the second varietal has a photoperiod of 6 hours. Plants20are nominally separated into a first group comprising plants20of the first varietal arranged on rows racks A1, B1, C1and D1, a second group comprising plants20of the first varietal arranged on racks A2, B2, C2and D2, a third group comprising plants20of the second varietal arranged on rows32-1and32-3of racks A3, B3, C3and D3, a fourth group comprising plants20of the second varietal arranged on rows32-2and32-4of racks A3, B3, C3and D3, a fifth group comprising plants20of the second varietal arranged on rows32-1and32-3of racks A4, B4, C4and D4and a sixth group comprising plants20of the second varietal arranged on rows32-2and32-4of racks A4, B4, C4and D4.

A time period, t, of 24 hours is separated into a first sub-period of 6 hours, a second sub-period of 6 hours, a third sub-period of 6 hours and a fourth sub-period of 6 hours. During the first sub-period, lights40for the first and third groups of plants20are turned on while lights40for the second, fourth, fifth and sixth groups of plants20are turned off. During the second sub-period, lights40for the first and fourth groups of plants20are turned on while lights40for the third, fourth, fifth and sixth groups of plants20are turned off. During the third sub-period, lights40for the second and fifth groups of plants20are turned on while lights40for the first, third, fourth and sixth groups of plants20are turned off. During the fourth sub-period, lights40for the second and sixth groups of plants20are turned on while lights40for the first, third, fourth and fifth groups of plants20are turned off.

Despite the presence of multiple varietals with different photoperiods, the same number of lights40are turned on with the same intensity at all times during time period, t. Moreover, since plants20of each of the first, second, third and fourth groups50are spread apart around grow room10(in the x, y and z-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Exemplary Scenario 6

In a sixth exemplary scenario, plants20are of two different varietals. The first plant varietal has a PPFD of half that of the second varietal. Both varietals have a photoperiod of 8 hours. Plants20are nominally separated into a first group comprising plants20of the first varietal arranged on rows32-1and32-3of all racks in grow room10, a second group comprising plants20of the second varietal arranged on rows32-2of all racks in grow room10and a third group comprising plants20of the second varietal arranged on rows32-4of all racks in grow room10.

A time period, t, of 24 hours is separated into a first sub-period of 8 hours, a second sub-period of 8 hours and a third sub-period of 8 hours. During the first sub-period, lights40for the first group of plants20are turned on while lights40for the second and third groups of plants20are turned off. During the second sub-period, lights40for the second group of plants20are turned on while lights40for the first and third groups of plants20are turned off. During the third sub-period, lights40for the third group of plants20are turned on while lights40for the first and second groups of plants20are turned off.

Despite the presence of multiple varietals with different PPFDs, and different numbers of lights40turned on at different times during time period, t, the cumulative heat output of lights40is maintained approximately constant by having half the number of lights at twice the intensity during the second and third sub-periods as compared to the first sub-period. Moreover, since plants20of each of the first, second, third and fourth groups50are spread apart around grow room10(in the x, y and/or z-directions), a likelihood of hotspots (due to heat from lights40that are turned on) or coldspots (due to a lack of heat from lights40that are turned off) within grow room10is reduced.

Interpretation of Terms

Unless the context clearly requires otherwise, throughout the description and the claims:“comprise”, “comprising”, and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”;“connected”, “coupled”, or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof; elements which are integrally formed may be considered to be connected or coupled;“herein”, “above”, “below”, and words of similar import, when used to describe this specification, shall refer to this specification as a whole, and not to any particular portions of this specification;“or”, in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list;the singular forms “a”, “an”, and “the” also include the meaning of any appropriate plural forms.

Words that indicate directions such as “vertical”, “transverse”, “horizontal”, “upward”, “downward”, “forward”, “backward”, “inward”, “outward”, “vertical”, “transverse”, “left”, “right”, “front”, “back”, “top”, “bottom”, “below”, “above”, “under”, and the like, used in this description and any accompanying claims (where present), depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein may assume various alternative orientations. Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly.

Although the operations of the method(s) herein are shown and described in a particular order, the order of the operations of each method may be altered so that certain operations may be performed in an inverse order or so that certain operation may be performed, at least in part, concurrently with other operations. In another embodiment, instructions or sub-operations of distinct operations may be in an intermittent and/or alternating manner.

Where a component is referred to above, unless otherwise indicated, reference to that component (including a reference to a “means”) should be interpreted as including as equivalents of that component any component which performs the function of the described component (i.e. that is functionally equivalent), including components which are not structurally equivalent to the disclosed structure which performs the function in the illustrated exemplary embodiments of the invention.

Various features are described herein as being present in “some embodiments”. Such features are not mandatory and may not be present in all embodiments. Embodiments of the invention may include zero, any one or any combination of two or more of such features. This is limited only to the extent that certain ones of such features are incompatible with other ones of such features in the sense that it would be impossible for a person of ordinary skill in the art to construct a practical embodiment that combines such incompatible features. Consequently, the description that “some embodiments” possess feature A and “some embodiments” possess feature B should be interpreted as an express indication that the inventors also contemplate embodiments which combine features A and B (unless the description states otherwise or features A and B are fundamentally incompatible).

While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are consistent with the broadest interpretation of the specification as a whole.

Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions, and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments.