System and method for sensing ammonia

A system and method for the monitoring of ammonia in a fluid. The ammonia monitoring system includes an ammonia sensor that is configured to detect trace amounts of ammonia (NH3) in a fluid (i.e., gas or liquid) that is pumped through it in real time. The real time ammonia sensor includes an interferometer configured to track the amount of ammonia that is pumped into the real time ammonia sensor. The ammonia monitoring system, via the real time ammonia sensor, is further configured to detect ammonia levels in industrial poultry houses and provide electronic feedback to the building's ventilation control system.

BACKGROUND

Ammonia is a byproduct of poultry excretion. Studies have shown that maintenance of low ammonia levels in industrial poultry houses is an important factor in increasing processing yield and feed efficiency, reducing bird stress and disease, and improving bird uniformity. Birds subject to high levels of ammonia weigh less, on average, than birds growing in low levels. Additionally, there is a greater spread in bird weight, and greater numbers of significantly undersized birds, making processing more difficult. High ammonia levels also negatively affect bird welfare at minimum and major levels. Levels above 35 parts per million (ppm) may adversely affect birds' growth, respiration, and disease immunity over time. At ammonia levels above 50 ppm, the spread of viruses, like Newcastle disease virus, can accelerate exponentially in a flock to the point where the whole flock can be lost. Conical lesions also dramatically increase at ammonia levels above 50 ppm. Above 100 ppm, birds may face immediate life threatening danger if action is not taken.

In order to control the amount of ammonia exposure, industrial poultry houses are ventilated based upon the levels of ammonia found in such poultry houses. However, humans vary in their ability to smell ammonia at levels below 50 ppm. Ammonia is currently managed by taking occasional point measurements using disposable colormatic tubes, and/or by tracking poultry house humidity as a loose proxy for ammonia, and then trying to set ventilation regimens accordingly. Such a process is burdensome, since it requires constant manual monitoring and adjustment. Further, ventilation can quickly become ineffective, particularly at nighttime. The building's lighting, ventilation, heating, humidity, and other parameters are typically adjusted automatically by a controller. The controller generally reduces ammonia levels by increasing ventilation, but excessive ventilation can reduce temperature inside the building, also negatively impacting bird health and increasing energy costs.

Therefore, there is a need for a real-time continuous ammonia sensor that can be used to continuously optimize ventilation. Further, there is a need for the real-time ammonia sensor to function in an automated feedback loop that keeps ammonia levels in the desired range using minimum ventilation.

SUMMARY OF INVENTION

The present invention provides an ammonia monitoring system. The ammonia monitoring system includes an ammonia sensor that is configured to detect trace amounts of ammonia (NH3) in a fluid (i.e., gas or liquid) that is pumped through it in real time. The real time ammonia sensor includes an interferometer configured to track the amount of ammonia that is pumped into the real time ammonia sensor. The ammonia monitoring system, via the real time ammonia sensor, is further configured to detect ammonia levels in industrial poultry houses and provide electronic feedback to the building's ventilation control system.

In one embodiment of the present invention, the ammonia monitoring system is further configured to display ammonia levels determined by the real time ammonia sensor in real time.

According to another embodiment of the present invention, the ammonia monitoring system is configured to log historical data, including data related to the ammonia levels detected by the real time ammonia sensor.

According to another embodiment of the present invention, the real time ammonia monitoring system is further configured to issue threshold alerts.

These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.

Both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the invention as claimed. The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute part of this specification, illustrate several embodiments of the invention, and together with the description serve to explain the principles of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 1-2, the present invention is directed to an ammonia monitoring system10. In an exemplary aspect, the ammonia monitoring system10illustrated inFIGS. 1-2is configured for use in poultry houses12. WhileFIGS. 1-2show the ammonia monitoring system10configured for monitoring air in poultry houses12, the ammonia monitoring system10can be used in a variety of settings in which the continuous monitoring for ammonia in a fluid (i.e., gas or liquid) is needed. For example, the ammonia monitoring system10can be configured for use in concentrated animal feed operations, such as, but not limited to, turkey grow-out and swine houses. Further, the ammonia monitoring system10can be utilized in utility industry settings. Such industrial settings include, but are limited to, remediating dangerous smokestack gases with ammonia and the monitoring of ammonia leaks when ammonia is utilized as a coolant. In addition, components of the ammonia monitoring system10as described below can be modified for use in environmental protection applications, including, but not limited to, measuring the ammonia level in water.

The ammonia monitoring system10includes a real time ammonia sensor20, a junction box14, intake hoses16and exhaust hoses17, and a dust and feather filter18. Further, the ammonia monitoring system10, and more specifically, the real time ammonia sensor20, are configured to interact with the house controller30(seeFIG. 2) of the poultry house12, and more specifically, with the ventilation components of the control system, including the house controller30, of the poultry house12.

In an aspect, the ammonia monitoring system10is configured for use in a poultry house12, with the junction box14, intake hoses16, exhaust hoses17, and dust and feather filter18configured to be located within the poultry holding area12a, and the real time ammonia sensor20located in the control room12b. In some aspects, the ammonia monitoring system10can also include additional in-house sensors (not shown) positioned within the poultry holding area12a. Such sensors can include, but are not limited to, humidity and temperature sensors, and can be found in the junction box14. Various fastening means, including, but not limited to, mounting brackets, may be used to secure the components of the ammonia monitoring system10at their respective positions within the poultry house12. While the junction box14and the real time ammonia sensor20can be mounted at various locations within the poultry holding area12aand the control room12brespectively, it is preferable that the junction box14and real time ammonia sensor20be mounted approximate to one another on a shared wall. For example, it is preferable to mount the real time ammonia sensor20approximately five feet off the ground to facilitate touchscreen operation with the junction box14mounted at a level about a foot below the bottom of the sensor. While the above describes the preferred mounting configuration, the ammonia monitoring system10is not limited to such. For example, other embodiments of the ammonia monitoring system10include having the ammonia sensor20and junction box14within the poultry house itself. Further, in some settings, the ammonia monitoring system10may not require a junction box14. All that is needed is for the ammonia monitoring system10to have ways to provide fluid from a poultry holding area12ato the real time ammonia sensor20.

In an aspect, the junction box14provides a protected location to house the junctions and cover holes drilled in the wall for the intake hoses16and exhaust hoses17to connect to the real time ammonia sensor20. In an aspect, the junction box14includes a mounting flange and is of sturdy enough construction to withstand pressure washing during house cleanout of the industrial poultry house12(and more specifically, the poultry holding area12a) between flocks. In an aspect, the junction box14has two air paths, one for the poultry house intake hose16and one for the exhaust hose17, both discussed in more detail below. In an aspect, the junction box14preferably includes a cover that is removable during end-of-cycle maintenance.

In an exemplary aspect of the invention, the intake hose16of the ammonia monitoring system10can be configured to be comprised of two sections, one section16bfor use in the control room side12band one section16afor use in the poultry holding area12a. In an exemplary aspect, both sections16a,16bof the intake hose16are of a standard size. In an exemplary aspect, the diameter of the sections16a,16bcan be ¼ inch. Hoses16a,16bwith larger diameters can require longer priming time as well as increased surface area for condensation, which can lead to a less efficient ammonia monitoring system10. However, the sections16a,16bcan have diameters of various sizes. In addition, it is preferable that the material of the intake hose16, including the different sections16a,16b, are made out of a material that does not absorb ammonia and is low in surface energy to prevent moisture adhesion. In an aspect, the intake hose16can be made out of materials including, but not limited to, polytetrafluoroethylene (PTFE). While PTFE can absorb ammonia, it is inert and does not change ammonia chemically. The lengths of the section16aof the intake hose16found in poultry holding area12aand the section16bof the intake hose found in the control room12bcan vary based upon the needs of the poultry house12. In an exemplary aspect, the ammonia monitoring system10can be distributed a 20-50 ft section16aof the intake hose16for the poultry holding area12aand with a 2 ft section16bof intake hose16for the control room side12b. However, in other aspects, each section16a,16bof the intake hose16can be shortened as required for the particular installation. The section16bof the intake hose16on the control room side12bis configured to connect to section16aof the intake hose16found in the poultry holding area12athrough the junction box14via a hole in the control room wall. The other end of the section16bof the intake hose16found in the control room12bis further configured to connect to the real time ammonia sensor20of the system10, as shown inFIG. 1. The section16aof the intake hose16stretching through the poultry holding area12aconnects to the short intake hose section16bthrough the intake path of the junction box14.

In an exemplary aspect, the sections16a,16bof the intake hose16are configured to be transparent to allow inspection for moisture, excessive dust, or debris in the intake hose16. However, in other embodiments, the intake hose16may be opaque. In an aspect, one end of the section16aof the intake hose16in the poultry holding area12acan configured to be connected with the dust and feather filter18. While the height of the end of the section16aof the intake hose16, and the coupled dust and feather filter18, as placed within the poultry holding area12acan vary. In an exemplary aspect, the end of the section16aof the intake hose16is oriented so that it takes in air at a level just above the height of a full-grown chicken. In an aspect, the intake hose16and dust and feather filter18are configured to be moveable (e.g., flexible and removable) so as not to impede workers and their equipment during house maintenance.

In an aspect, the dust and feather filter18is configured to block objects and dust, but must not reduce the filtered fluid's humidity or affect the ammonia level in the air. The dust and feather filter18can be configured out of suitable materials that prevent dust particles, feather, and bugs from entering the intake hose16. In an aspect, the ammonia monitoring system10can utilize a dust and feather filter18comprised of reticulated foam (e.g., INOAC's EZ-Dri polyether-polyurethanane foam) and a fine mesh wire screen. Filter types known to those of ordinary skill in the art can be utilized in other embodiments of the present invention.

As illustrated inFIG. 1, the ammonia monitoring system10includes an exhaust hose17. While the exhaust hose17can be of any length, the exhaust hose17does not need to be extremely long because the exhaust hose17is used to return air to the poultry house. Further, while the diameter of the exhaust hose17may be of any size, it is preferable that the exhaust hose17diameter be of a different diameter than the section16bof the intake hose in the control room12bto preclude cross connection with the ammonia sensor20. Further, it is preferable that the exhaust hose17include an exhaust filter19to prevent backflow of dust when the ammonia monitoring system10is not circulating air. In an aspect, the exhaust filter19can be changed or cleaned with water or forced air.

As shown inFIG. 2, the real time ammonia sensor20includes a housing22, a user interface40, and external connections50. In addition, the housing22of the real time ammonia sensor20contains various hardware and software components discussed in further detail below. In an aspect, the housing22is configured to be rugged, and made of a sturdy material, including but not limited to, sheet metal or molded plastic, sufficient to protect the inner components of the ammonia sensor20and meet various safety and regulatory requirements. In an aspect, the housing22can include a removable filter cover, giving access to certain components of the ammonia sensor20, including an ammonia filter cartridge, discussed in more detail below. In the preferred embodiment of the present invention, the housing22is configured to notify (e.g., via a switch) the various hardware and software components of the ammonia sensor20when the filter cover is removed or reinstalled.

In an aspect, the real time ammonia sensor20includes a user interface40. In an exemplary aspect, the user interface40comprises a single, large, backlit color touchscreen on which all user controls and displays reside. In such an aspect, the user interface40can include an interactive touchscreen. While the preferred embodiment of the present invention uses an interactive touchscreen, the ammonia sensor20can include other types of user interfaces40, including, but not limited to, a combination keypad and display screen, and the like. In some embodiments of the present invention, it may be desirable for the ammonia sensor20not to have any direct human assessable interface, limiting the control of the ammonia sensor20to authorized individuals remotely through a wireless or wired connection, discussed in more detail below. Specific controls and displays, and their functions, are discussed in more detail below. While the dimensions of the user interface40and the housing22can be of various combinations, it is preferable that the touchscreen display40be approximately 6″×4.5″ and the housing22not be more than 7″×9″ in area, and not more than 3″ deep.

As shown inFIG. 2, the real time ammonia sensor20provides external connections50that facilitate the monitoring of ammonia levels within the poultry holding area12a, as well communication with the house controller30. In an exemplary aspect of the ammonia sensor20shown inFIG. 2, the bottom of the housing22provides five external connections50, including two fluidic connections52a,52b, a communication connector54, a power connector56, and an auxiliary data port58. In other aspects, the ammonia sensor20can include more or fewer external connections50, as well as connections of different types.

The fluidic connections52include an intake port52a(“IN”) and an exhaust port52b(“OUT”), which connect to the intake hose16and the exhaust hose17, respectively. The intake port52aand the exhaust port52bconnect the intake hose16and the exhaust hose17to components within the housing22of the ammonia sensor20. Such components include, but are not limited to, a fluid circulation subsystem (FCS)100and a chemical sensor module (CSM)200, both shown inFIGS. 3-7and discussed in more detail below. These ports52a,52bmay include nipples that connect to the respective intake hose16and exhaust hose17. As discussed above, it is preferable that the nipples of the intake port52aand the exhaust port52band intake hose16and exhaust hose17are of different sizes to preclude cross connection. Further, it is preferable that the intake hose16and all other parts exposed to air on the inlet side be made of materials that do not off-gas, and do not absorb ammonia or other gases. This material, as discussed above, can include, but is not limited to, polytetrafluoroethylene.

In an aspect, the communication connector54(CTRL) is configured to output real-time information to various components associated with the ammonia monitoring system10. In an aspect, such real-time information can include, but is not limited to, NH3and humidity levels as well as temperature. In an aspect, the communication connector54can be configured to output the real-time information to the house controller30. In an aspect, the house controller30is configured to control lighting, ventilation, heating, humidity, and other parameters in the poultry holding area12a. In an exemplary aspect, the house controller30is configured to control the ventilation of the poultry house12based upon the notification from the ammonia monitoring system10that the concentration of ammonia in the poultry housing area12bhas reached a certain level or passed a given threshold. Specific format and content for the real time information transmitted by the communication connector54are discussed below. Various connectors can be used with the communication connector54, dependent on the needs of the house controller30and various components. In some embodiments of the present invention, the various connectors may have a standard connector on the end that connects to communication connector54of the ammonia sensor20, with the other end being defined by the type of house controller30. The communication connector54could also be achieved wirelessly by adding an external wireless dongle at the communication connector54, or by using an internal modem.

In an aspect, the power connector56is configured to accept a plug-in power cable. The power cable can be a standard 110 VAC, 3-prong cable approved for use in the United States. Other power cables may be utilized as well. In some embodiments of the present invention, the power cable is hardwired into the ammonia sensor20, with an appropriate strain relief. Power can be provided through various means known in the art. In another aspect, the ammonia sensor20can include an internal power source, including, but not limited to, a battery, solar panel assembly, or the like. In such aspects, a power connector56may not be necessary.

In an aspect, the ammonia sensor20can include auxiliary data ports58. In an aspect, the auxiliary data ports58can be configured to include a USB port. In such aspects, the USB port of the ammonia sensor20can be configured to be compatible with standard USB cables. In other aspects, the ammonia sensor20can have other auxiliary data port types58that are compatible with various other connectivity means known in the art. For example, some embodiments of the ammonia sensor20can include a dedicated memory stick configured to removably couple to the auxiliary data port58. The memory stick may include pre-loaded software for installing a simple application on a user's computer. The memory stick can be configured to connect to the ammonia sensor20to download data, which can then be transferred to a user's own computer, where software will retrieve it for the user to store, display, and manipulate.

In an aspect, an auxiliary data port58can be configured to provide the interface for calibration and diagnostics, as well as the uploading of new software. In such aspects, the auxiliary data port58can be provided as a separate output from the communication connector54to allow a user to connect to the auxiliary data port58and download historical or real-time data without interrupting the output signal to the house controller30. Preferably, the communication connector54should be of a different physical connection type from the auxiliary data port58to preclude cross-connection.

As discussed above, the ammonia sensor20includes hardware and software components. In an aspect, the hardware components of the ammonia sensor20include three interdependent subsystems organized by hardware function—not by physical location or implementation. In the aspect shown inFIG. 3, the subsystems include a fluid circulation subsystem (FCS)100, a chemical sensor module (CSM)200, and a monitor controller (MC)300. The FCS100, CSM200, and the MC300work together to monitor the concentration of ammonia in the poultry holding area12b, and alert the house controller30to ventilate the poultry holding area12bupon reaching a certain threshold concentration.

In an aspect, the FCS100can include a pump110and valve108that interact with an ammonia filter104, the junction box14, and all external hoses (intake16and exhaust17and respective filters18,19) and internal hoses discussed in more detail below. Components of the FCS100can be connected to the CSM200. In an aspect, the CSM200includes a laser240, waveguide230, camera250, and mount (shown inFIGS. 5-6). In an aspect, the FCS100and CSM200are connected to the MC300. In an aspect, the MC300is an embedded system or single board computer which controls the FCS100, the CSM200, image processing from the CSM200, data processing from any additional sensors, the touchscreen display40, user Interface connections, and power conditioning. In an aspect, the MC300provides power and commands to all electronic components of the FCS100and CSM200, and receives data from the CSM200. The MC300can also input and output data to the communication connector54and auxiliary data ports58, including receiving commands. In the preferred embodiment, 110 VAC power enters through the power connector56and is converted to required levels by the internal electronics of the MC300.

FIG. 4is a block diagram showing connections and flow in the FCS100to various components of the ammonia monitoring system10. In one embodiment, fluid enters on the left through the intake port52a(labeled air inlet inFIG. 4), and is immediately split into two paths: a filtered path102going through the ammonia filter104, the unfiltered path106bypassing the ammonia filter104. In an aspect, the ammonia filter104filters ammonia out of the fluid, but should not affect its humidity level, temperature, or other characteristics. The ammonia filter104can be made of a variety of filter material comprised of but not limited to, copper sulfate pentahydrate, copper bromide, and the like.

Both the filtered path102and the unfiltered path106terminate in inlets to a valve108, which selects either the filtered fluid (i.e., from the filtered path102with the filter104) or the unfiltered fluid (i.e., unfiltered path106) to pass through via additional tubing112to a waveguide of the CSM200. In an aspect, a pump110can control the flow of the fluid to CSM200. By having a filtered path102and an unfiltered path106, the ammonia sensor20, and more specifically the CSM200, can be configured to self-calibrate on a regular basis to reduce sensor drift and maintain accuracy. For each sense cycle, the filtered fluid is first measured to establish a zero-ammonia baseline, in order to cancel waveguide drift. The filtered path102and the unfiltered path106should be balanced in terms of the pressure drop through the path, the time travel for fluid through the path, and the relative humidity. In another aspect, to further ensure accurate measurement, the FCS100can utilize a temperature sensor and a temperature controlling mechanism (e.g., a fan or heating coil) to regulate temperatures of the fluids passing through the filtered path102and unfiltered path106.

The pump110, whose location in the stream can change (i.e., the pump110can be external to the ammonia sensor20), either pushes or pulls fluid from the poultry holding area12athrough the ammonia sensor20, including to the CSM200, for ammonia level measurement. The fluid exits the CSM200via additional tubing114and passes through the exhaust port52b, which passes the fluid to the exhaust hose17. Table 1 below discloses parameters of the various components of the FCS100according to an aspect.

In an alternative aspect, the ammonia sensor20can contain two valves108, and fluid is continually pumped through both the filtered path102and unfiltered path106so that there is no latency between the environmental characteristics of the fluid the filtered path102and unfiltered path106. In such an aspect, fluid from the path not being pulled or pushed through the CSM200bypasses the CSM200and is coupled with fluid coming out of the CSM200to be exhausted through the exhaust port52b.

In another aspect, an ammonia monitoring system2000can be configured to provide a multi-valve switching mechanism for multi-point sampling in the poultry holding areas2012a, particularly for the mega-coops, as illustrated inFIG. 16. As shown, multiple intake hoses2016and filters2018can be found in multiple poultry holding areas2012a. The multiple intake hoses2016can be configured to fit a junction box2014with a multi-valve switching mechanism (not shown) that switches between multiple inlets. In such an aspect, the ammonia sensor2020(in control room2012b) and the intake switching (within the junction box2014) are synchronized by a controller in the ammonia sensor2020. In an exemplary aspect, the switching mechanism can be modular so that additional intake lines2016can be added when needed. A significantly greater area can be covered with this method. However, since only one intake hose2016can be sampled at one time, the sampling rate per intake will be longer. The intakes2016not currently being sampled can be continuously purged by a pump in the junction box2014; this will decrease the need to prime the lines when the ammonia sensor2020switches to a new intake2016.

While it is important for the intake port52aand exhaust port52bto remain unblocked, the preferred embodiment of the ammonia monitoring system10, and more specifically the FCS100, is configured to operate without causing self-inflicted damage if either port becomes blocked for an indefinite period of time. Further, the ammonia filter104and/or neutral filter should be replaced as a part of normal maintenance at the end of each flock, nominally 8 weeks.

FIGS. 5-8illustrate components of the chemical sensor module (CSM)200. The CSM200can be configured to utilize optical interferometry to sense the amount of ammonia in the fluid. In an exemplary aspect, the CSM200contains a Mach-Zehnder interferometer. In other aspects, other optical interferometers, including, but not limited to, Michelson, Fabry-Perot, Twyman-Green, Sagnac, Rayleigh, and Jamin interferometers can be used. The interferometer includes a sense channel234coated with a polymer that selectively changes its index of refraction when exposed to ammonia, discussed in detail below.

Fluid, labeled as “fluid flow” at the top ofFIG. 5, is pumped in from the right through an inlet tube210, and passes through a sealed chamber220(i.e., flowcell) over a waveguide230. At the same time, a low power laser240launches a beam of monochromatic light into the waveguide230. Interference patterns are displayed on a camera250(e.g., a camera chip250) or otherwise captured by another form of optical detector, at the output side of the CSM200. In an aspect, the CSM200utilizes a UI-1542LE-M model camera250from IDS Imaging.

In an aspect, as illustrated inFIGS. 6-8, the waveguide230is a stacked thin film structure with a base of optical glass, a thin core layer of a higher-index material, and an upper cladding layer into which are etched the long, narrow channels234,236. In an aspect, the waveguide230consists of an input grating232, one or more pairs of parallel channels—e.g., a sense channel234and a reference channel236—and one or more output gratings238. For example, in the exemplary aspect illustrated inFIG. 7, the waveguide230can be configured to have four pairs of sense channels234and reference channels236, as well as four input gratings232and output gratings238. The CSM200can be configured for the laser240to be oriented under the waveguide230so that the light of the laser240enters the input grating232from the bottom of the waveguide230, and is refracted to travel down the length of the sense channel234and reference channel236(left to right inFIGS. 5-7).

In an aspect, the sense channel(s)234is filled with a chemically sensitive polymer whose index of refraction changes in proportion to adsorption of the corresponding chemical, causing the speed of light in that polymer to change correspondingly. Further, the chemically-sensitive polymer that is utilized is configured to adsorb the chemical as the polymer is exposed to the chemical, and desorbs as the polymer is exposed to a fluid without the chemical. In an exemplary aspect, the chemically-sensitive polymer is an ammonia adsorptive polymer, whose index of refraction changes in proportion to ammonia adsorption. The polymer used to coat the sense channel(s)234in the preferred embodiment of the present invention is a polyvinylphenol (PVP) titrated to a pH of 7 with potassium hydroxide covered with a top coat of ethyl cellulose. The reference channel236is covered so as to not be affected by the polymer coating (i.e., it is not adsorptive of ammonia).

In an exemplary aspect, the sense channel(s) is coated with PVP at a thickness of the PVP is 1600 Angstroms, while the thickness of the ethyl cellulose is 5000 Angstroms. In other embodiments of the invention, other coatings and thicknesses can be used. The speed of light in the sense channel234and the reference channel236will be different to a degree proportional to the amount of ammonia in the fluid sample. In an aspect, both the sense channel234and the reference channel236are either equally adsorptive to water vapor, or the CSM200is calibrated and inclusive of a humidity sensor, or the ammonia monitoring system10contains filters which dampen humidity transients in the fluid coming into the CSM200, so that the overall effect of humidity on system performance is immaterial. In an exemplary aspect, both the sense channel234and the reference channel236are also covered with a protective coating, permeable to ammonia, to reduce fouling.

In an aspect, as the sense channel234and reference channel236are exposed to the ammonia-containing fluid (i.e., the fluid that has gone through the unfiltered path106, such path potentially containing a “neutral” filter which does not affect the chemical composition of the fluid but does balance pressure and flow through the unfiltered path with that of the filtered path102), ammonia adsorbs to the sense channel234in proportion to the amount of the exposure (i.e., the more time exposed to ammonia, the more ammonia is adsorbed). Once the waveguide230has been exposed for the desired time, the waveguide230can then be exposed to the filtered fluid (i.e., the fluid that has gone through the filtered path102and filter104). Light from the laser240is coupled into the waveguide230and a portion of this coupled light (its evanescent field, as shown inFIG. 8) travels through the polymer coating that has been applied to the surface of the sense channel234. Laser light also travels down the adjacent reference channel236. The interference pattern generated by the optical interaction of light from the sense channel234and the reference channel236is imaged on the camera250. The sense channel234, and more specifically the ammonia sensitive polymer, will capture or release ammonia molecules in proportion to the concentration of ammonia in the fluid, changing the index of refraction of the ammonia sensitive polymer on the sense channel234, which therefore alters, in a quantifiable way, the interference pattern created by the recombination of the light passing through the sense channel234and the reference channel236. The phase shift of the interference pattern, which, in an exemplary aspect, is proportional to the concentration of the ammonia, is determined using a processor running image processing algorithms, discussed in more detail below.

After exiting the right-hand side of the sense channel234and the reference channel236, both light beams are again refracted and combined by the output grating238, creating, as mentioned above, an interference pattern on the surface of the two-dimensional camera250or other form of optical detector. If ammonia is present, the light waves in the sense channel234and the reference channel236will travel at different speeds, and one will arrive at the output grating238before the other, causing a phase shift in the interference pattern on the camera chip250that is proportional to ammonia concentration. The MC300analyzes the image from the camera chip250and measures the phase shift (the movement in the interference pattern over time as the ammonia concentration changes) to determine the ammonia concentration using calibration coefficients associated with the ammonia sensor20already accessible (e.g., stored within the MC300). These coefficients may be updated through various means as well.

WhileFIG. 6depicts a single pair of channels234,236on the waveguide230, waveguides230may also contain multiple channel pairs (e.g., seeFIG. 7), each with the same or different polymer pairs, to sense multiple analytes in the air sample, or to increase reliability. Table 2 below provides the characteristics for the CSM200according to one exemplary aspect.

In an aspect, the MC300is resident in the ammonia sensor20and is not accessible to the user except functionally via the user interface40or external connectors50. In an aspect, the MC300includes the power control system of the ammonia sensor20. In an aspect, the power control system of the MC300includes a current monitor to detect off-nominal conditions, discussed in more detail below. In an aspect, the MC300includes on-board memory. In an exemplary aspect, the memory of the MC300is configured to be of a nonvolatile type and provides enough on-board memory to store three days' worth of readings at the shortest reading interval, which can be set by the user. In such aspects, the memory of the MC300is erased on a first-in, first-out basis when the memory becomes full. In an aspect, the memory of the MC300is configured to maintain a system log file and user-defined identification data. In an exemplary aspect, the memory of the MC300is configured to have 1 16 k of user-defined identification data and at least 512 k to maintain a system log file. In an aspect, the MC300is configured to include a real time clock (RTC) which continues to track time even when the system10, or more specifically the ammonia sensor20, is powered down. It is preferred that the RTC shall maintain an accuracy of better than ±6 hours per year for up to three years.

In other embodiments, the location and association of the components of the ammonia monitoring system10may vary from what is described above. For example, the junction box14may house various components, including, but not limited to, the pump110, valve108, and ammonia filter104. In other embodiments, the junction box14may also include the CSM200and the FCS100, with the MC300being housed separately in the housing22of the ammonia sensor20. In addition, some elements as discussed above may not be utilized in other embodiments. For example, in an aspect, the ammonia monitoring system10can be configured not to include a junction box14: the various pumps110, valves108, the filter104, and hoses that form the filtered path102and unfiltered path106can be exposed, or be contained within the housing of the ammonia sensor20.

In an aspect, the MC300is configured to control overall operations of the ammonia sensor20. In an aspect, the MC300is configured to: control a user interface40, which can comprise a touchscreen display; interface with the communication connector54and auxiliary data ports58; interface with the user via the user interface40to set options and conduct maintenance; manage power input to the ammonia monitoring system10; detect system faults and respond to them; save ammonia concentration data to a time-stamped data file; save significant events to a System Log; and detect and react to exceptions and errors. These functions can be implemented and run through various applications, including, but not limited to, Labview software from National Instruments.

In an aspect, the MC300is further configured to control the operation of the FCS100and the CSM200. In an aspect, the MC300is configured to control various functions of the CSM200. In an aspect, the MC300can be configured to determine the ammonia concentration as well. The MC300is configured to use applications, including an ammonia detection application discussed in detail below, to determine the ammonia concentration. In addition, the MC300can be configured to process the images from the CSM200, including image cropping, to determine the ammonia concentration. In an aspect, the MC300can determine the ammonia concentration through a method600as illustrated inFIG. 9. In an aspect, the ammonia concentration is done by determining an appropriate measurement zone of the image (step610), determining the interference pattern period within the measurement zone (step620), determining the phase shift that has occurred from the interference pattern period (step630), correlating the phase shift data with calibration data to obtain an analyte concentration reading (step640), and processing the stream analyte concentration reading to eliminate noise and other potential faulty data (step650). In an exemplary aspect, the ammonia detection application can perform the method600.

The MC300can determine the appropriate measurement zone for the images collected by the camera250in various ways (step610). In an aspect, the MC300can determine the appropriate measurement zone by evaluating the relative high and low intensities of the images captured by the camera250. Other known methods can be used to determine the appropriate measure zone.

Once the measurement zone has been determined, the MC300can determine the interference pattern period within the measurement zone (step620). In an aspect, the MC300can utilize image processing algorithms to determine the interference pattern period. In an exemplary aspect, the MC300can utilize a spatial Fourier transform algorithm. In such an aspect, the spatial Fourier transform algorithm is used to get the spatial frequency components of the interference pattern, and more specifically to find the dominant spatial frequency component. In other aspects, other algorithms or methods can be used to determine the interference pattern frequency and components other than the dominant frequency component of the interference pattern can be used to determine concentration.

Once the interference pattern's dominant spatial frequency has been determined (step620), the MC300can find the phase shift that has occurred from the interference pattern period (step630). In an exemplary aspect, the MC300can use the dominant spatial frequency component that was determined by the Fourier transform algorithm. In such an aspect, a phase demodulation can use the dominant frequency component to measure the phase shift. In other aspects, other processes can be used to determine the phase shift measurement.

Upon determining the phase shift measurement data, the MC300can then correlate the phase shift data with calibration data to obtain an analyte concentration reading (step640). In an exemplary aspect, the phase shift data can be multiplied by a calibration coefficient to determine the ammonia concentration reading.

Once the analyte concentration reading is determined, the MC300can process the concentration reading to eliminate noise and other potential faulty data (step650). This can be done by using weighted averaging algorithms or other signal processing techniques. In addition, other environmental conditions can be considered as well to eliminate faulty data. For example, the analyte concentration reading can be adjusted according to the current humidity level. Such information can be obtained through humidity sensors. The analyte concentration reading can then be displayed by the user interface40, and can be utilized to determine when the ammonia level in the poultry holding area12ahas reached a level that necessitates the activation of the house controller30to ventilate the holding area12a.

As discussed above, the MC300is configured to control the operation of the ammonia monitoring system10. In an aspect, the MC300is configured to provide simple operations for a user. As such, in exemplary aspects of the system10, the ammonia sensor20has a limited number of modes: a measurement mode, a standby mode, a system error mode, a maintenance mode, and a calibration and diagnostic Mode. While it is preferred that the ammonia sensor20be limited to these five modes, other embodiments may include more optional modes, different modes, or fewer modes.

FIGS. 10-12depict screen illustrations of the modes discussed above as displayed to a user according to an aspect and are not meant to suggest specific layout or artwork for the screen. The screens shown are meant to correspond to the display/user interface40ofFIG. 2. As shown inFIGS. 10-12, the display40includes certain information provided to the user, including the status of which mode the ammonia sensor20is presently operating, and any corresponding readings. For example, the display40can include a measurement status indicator. As shown inFIG. 8, the measurement status indicator shows that the system is in standby mode. In standby mode, the ammonia sensor20is not operational, and displays “STANDBY” on its screen. This mode is generally used during times when no animals are present in the poultry holding area12a.

When in the measurement mode, the ammonia sensor20can be configured to continuously measure, display, and record ammonia levels according to system presets, which can be adjusted by the user. In an additional aspect, when in measurement mode, the ammonia sensor20can be configured to notify the house controller30with the ammonia level reaches a certain level or threshold. In an aspect, the ammonia sensor20can continuously pass along information related to the ammonia levels to the house controller30, and the house controller30can be configured to determine with the supplied ammonia levels surpass safe ammonia levels that necessitate ventilating the poultry holding area12a.

As shown inFIG. 11, the measurement status indicator shows that the system is in the MEASUREMENT mode, displaying a “NORMAL” to indicate the system is presently taking measurements, and the last measurement was within the Normal threshold set by the user. In an aspect, when the ammonia sensor20finds that a last measurement of ammonia is above a caution threshold set by the user, a “CAUTION” measurement status indicator can be displayed. Likewise, when the ammonia sensor20finds that a last measurement of ammonia is above a user-set Warning threshold, a “WARNING” status indicator can be displayed. Other embodiments may use descriptive words other than “Normal,” “Caution,” or “Warning.” In other aspects, colors (e.g, green, yellow, and red) can be associated and displayed to indicate the status of the ammonia levels measured.

In addition to the measurement status indicator, the display40can include other information. Such information can include a last measurement numerical indicator, a data/time display, and the filter capacity display. The numerical indicator indicates the last ammonia level reading taken. In standby mode, this indicator reads “--.-”, as shown inFIG. 10. Further, it is preferable that the numerical indicator display the amount with 0.1 ppm precision. The data/time display shows the present date and time, with minute precision, and is user adjustable in the preferred embodiment. Also in the preferred embodiment, the date/time display adjusts for daylight savings time (US and Europe) and leap years. Lastly, the filter capacity display indicates the status, present capacity, or remaining life of the ammonia filter. In an exemplary aspect, the MC300, through various means discussed below, keeps track of the total amount of ammonia to which the ammonia filter104has been exposed, as well as the time of exposure, and calculates remaining filter life. In an aspect, the numerical indicator can have colors associated with the remaining capacity of the filter104: green for high capacity, yellow at a lower value, and red at a still lower value. In an aspect, when the NH3filter capacity is at zero, the ammonia sensor will no longer take readings, and displays a “change filter” message. The default threshold values for the color changes can be changed based upon the user's preference. In an exemplary aspect, the number is automatically reset to its maximum each time the user goes through maintenance mode. In some embodiments of the present invention, the filter capacity display will notify the user when a new filter has been installed improperly.

Referring toFIGS. 10-11, the display40can be configured to include Main Menu Controls. In an exemplary aspect, the Main Menu Controls displayed can include a Start/Pause Measurement button, a Performance Maintenance button, a Set Options button, and a Return to Display button.

In an aspect, the Start/Pause Measurement button toggles between ‘Start’ and ‘Pause’ measurement. When pushed from Standby mode, it places the system in Measurement mode. When pushed from Measurement mode, it places the system in Standby mode. The Perform Maintenance button launches Maintenance mode, described in more detail below. The Set Options button opens a lower level of menus and keypad displays that allow the user to change system options. The Return to Display button returns to the graphical display of historical measured NH3levels, as shown inFIG. 12. When in Standby Mode, the display is static and shows the most recent readings. When in Measurement Mode, the display is dynamic and continues to update. The Measurement Status Indicator, Last Measurement Numerical Indicator, Filter Capacity Indicator, and Date/Time Display continue to be displayed, independent of whether the graphical display or the menu is included in the embodiment.

As discussed above, the Graphical Display is initiated from the “Return to Display” button on the Main Menu.FIG. 12illustrates the Graphical Display in Measurement Mode. As shown, the only control on the Graphical Display screen is the “Menu” button, which returns to the Main Menu (while remaining in either Standby or Measurement Mode). In other embodiments of the present invention, other buttons may be included on the Graphical Display.

The Graphical Display shows historical ammonia level readings. In Measurement Mode, it updates in real time. In Standby Mode, it shows the most recent readings. The ‘x’ axis is time; ‘y’ axis is ammonia level in ppm. Both axes are user-adjustable and can autoscale, as necessary and as desired, to accommodate the data. In an aspect, the lines can be displayed in a certain color for certain threshold levels of ammonia (e.g., yellow and red lines indicate the user-adjusted “Caution” and “Warning” thresholds, respectively). Date range limits on the display can be set by the user.

In an aspect, the parameters are displayed as a series of points connected by straight lines, during periods where the ammonia sensor20was in Measurement Mode. If the ammonia sensor20was placed in Standby Mode at any point during the time interval displayed, values during those durations are not displayed on the display, appearing as gaps in the line. WhileFIG. 12shows the display illustrating the numbers using a traditional x and y axis that correspond to time and ammonia levels, other types of graphical representations may be used in other embodiments, including, but not limited, bar charts with min, max, and current levels.

In an aspect, the ammonia sensor20and the overall ammonia monitoring system10enters Measurement mode: (a) when “Start Measurement” is selected from the Main Menu; or (b) when the system returns from System Error Mode, if Measurement Mode was the last known mode (note: on return from a power dropout, the system starts in Standby Mode).

In Measurement Mode, the display40illustrates the Graphical Display as inFIG. 12. The user may toggle between the Graphical Display and the Main Menu without leaving Measurement Mode. The ammonia sensor20continuously takes ammonia level readings at the time interval specified by the Measurement Interval parameter, according to the behavioral flow shown inFIG. 13.

When the Measurement Mode is started (1000), the graphical display is changed (1001) to show something similar to that presented inFIG. 12. The pump110, laser240, and camera250are turned on and initialized as appropriate (1002). Using image processing algorithms, which in one embodiment includes the use of Fourier transforms, the system10begins tracking both the phase shift that occurs in the interference pattern detected by the camera (1003) In an aspect, the system10can also track the relative humidity (1004). Using a real-time clock, a counter is set (1005) for a duration. In an exemplary aspect, the counter is set for 20 seconds. In other aspects, the duration can vary depending on the environment in which the ammonia monitoring system10is utilized. Once the counter is set, the valve108can be switched (1006) so that fluid filtered by the ammonia filter104(filtered path102) travels through the flow cell220and over the waveguide230(i.e., unfiltered fluid from the unfiltered path106, containing, in an exemplary aspect, the neutral filter, has already been exposed to the waveguide230and the sense channel234, with ammonia being adsorbed).

Once filtered fluid is flowing, the MC300can then acquire phase shift data through images of the interference pattern from the waveguide230captured by the camera250and utilizing image processing algorithms (steps1007and1008). In an aspect, the ammonia monitoring system10first takes the derivative (or slope) of the phase data, and then filters the derivative phase shift data to remove high frequency noise components (step1007). The maximum negative value of this processed data is then found (1008). Since the speed of the chemical adsorption and desorption of the ammonia responsive polymer coating of the sense channel234is proportional to the concentration of ammonia in the sample, the derivative approach can be used, preserving filter capacity. The value found in (1008) is then multiplied by a calibration coefficient, which can be adjusted according to the current humidity level (i.e., performed at step1005) (1009).

If the value obtained is within a reasonable range and not dramatically different from the last measurement (1010), and if no other errors or failures are detected in the sensor, the value is then logged and passed along for graphical display as well as for communication to the Controller (1012). Errors would cause the sensor to enter System Error Mode (1011). If no errors are found, the system10waits until the countdown has reached zero (1013) and, when this has occurred, the valve108is switched so that the poultry house fluid is passed unfiltered through the flow cell220to the waveguide230(1014). The countdown clock is then reset (1015), allowing the waveguide230, and more specifically the polymer of the sense channel234to adsorb ammonia from the poultry house. In an exemplary aspect, the clock is reset can be set to 100 seconds. In other embodiments, other time periods can be utilized. When the countdown again reaches zero (1016) and the ammonia sensor20has not been asked to pause or standby (1017), the ammonia sensor20then resets the countdown and switches back to the filtered state (1005and1006). Otherwise, the system10enters standby mode (1018).

In an aspect, the ammonia sensor20exits measurement mode when: (a) the user selects “Pause Measurement Mode” from the Main menu; (b) a System Error occurs, or (c) the system is powered down. The ammonia sensor20enters Standby Mode when: (a) the system is powered up; (b) the user selects “Pause Measurement” from the Main Menu, or; (c) the system recovers from a System Error and the last state before the error was Standby Mode. When the Graphical Display is shown on the user interface40during Standby mode, only historical data is presented, with the time intervals during which the system is in standby having no data appearing as gaps in the curve. In one embodiment of the present invention, if the user invokes Standby mode while the ammonia sensor20is taking a measurement, the ammonia sensor20interrupts the measurement, and then enters Standby Mode.

In Standby mode, the various components of the ammonia monitoring system10can be put into the following status: the valve108can be set to “Sense” (unfiltered) input, to minimize flow through the ammonia filter104, the pump110can be turned off, and the CSM200, including the laser240and camera250, can be turned off as well. Further, the communication connector54can hold a ‘no data’ reading.

In an aspect, the ammonia sensor20enters SYSTEM ERROR mode when it encounters certain error conditions. In some embodiments of the present invention, the System Error Mode is identical to Standby Mode, except that it is initiated by certain System Errors that require measurements to stop in order to prevent possible damage to the ammonia sensor or the reporting of ‘junk’ data. In System Error Mode, the Status Indicator shown on the user interface40can read “SYSTEM ERROR”. In an aspect, when the error condition is corrected, the ammonia sensor20can exit System Error Mode and return to the last saved mode, either automatically or by user action. The System Log can record time & date for entry into, and exit from, System Error mode.

Maintenance mode places the ammonia monitoring system10in a safe state and guides the user through maintenance actions to be performed at the end of each flock cycle. Maintenance on the ammonia monitoring system10is intended to be carried out at the end of each flock cycle, but can be performed any time the user desires. The ammonia monitoring system10may incorporate a maintenance countdown, which alerts the user to when the system needs regularly scheduled maintenance. In addition to keeping a ‘maintenance countdown’, the ammonia monitoring system may keep a separate ‘Replacement Countdown’, and shall alert the user via a Touchscreen text message when a replacement ammonia sensor is due.

FIG. 14illustrates an exemplary aspect of system behavior in Maintenance Mode (method1100). The User enters Maintenance mode by selecting “Perform Maintenance” from the main menu. The ammonia sensor configures the system as if in Standby Mode. A series of Text Messages on the Touchscreen guides the user through the maintenance steps, and the ammonia sensor performs several self-tests to ensure maintenance was carried out properly. The screen messages may include graphics that illustrate the task to be performed. In an aspect, the System Log records the start and end time/date of each maintenance.

As shown inFIG. 14, the maintenance mode is started by selecting the maintenance mode (step1101). When started, the system10, through the MC300, sets the valve108to sample input (open to unfiltered path106) (step1102), turns the pump110off (step1103), and turns the laser240and camera off (step1104). In addition, the MC300can call upon the system log to record the initiation of the maintenance (step1105). The ammonia sensor20, via the user interface40, can then prompt the user to open the filter door (step1106). The MC300can then wait to receive confirmation that the filter door has been open, via a switch or some other means of sensing the door is open (step1107). Upon receiving the notice of the door being opened, the MC300can then prompt the user to replace the ammonia filter104, and potentially the neutral filter as well, on the user interface40(step1108). In addition, the MC300can prompt the user to confirm, via the user interface (e.g., select OK tab) when done.

Upon receiving confirmation of the replacement (e.g., selection of the OK and closing of the door) (step1109), the MC300can prompt the user to change the dust and feather filter18and exhaust filter19of the intake hose16and exhaust hose17(step1110). In an aspect, the MC300can prompt the user to confirm the change by providing notification (e.g., OK tab). In other aspects, sensors employed at these filters18,19can be utilized, reporting back to the MC300. Once the cleaning has been confirmed (step1111), the MC300can notify the user via the interface40that a system self check will be performed (step1112). The MC300can then perform a self check by using a sample measurement for each measurement mode (step1113). Once completed, the MC300can call upon the pump to see if the current is normal (step1114). If the reading is not normal, a fluid circulation exception is generated (step1115), and a maintenance error, along with the time, data, and error info is recorded to the system log (step1118). If the pump circulation is normal, then the MC300checks to see if the reading is physically possible, perhaps by comparing it to recent readings (e.g., checking the sanity as shown inFIG. 14) (step1116). If the reading is not, a bad reading exception is generated (step1117), and the maintenance error is recorded as well (step1118). If the reading is acceptable, the MC300notifies the user, stating that maintenance is complete, and provides a means of confirmation to the user (e.g., the OK tab) (step1119). If the circulation or reading is not acceptable, the ammonia monitoring system10enters into system error mode (step1120). Upon receiving the input of OK from the user (step1121), the MC300will write that the maintenance has been completed in the system log, along with the time and date (step1122). In an aspect, the concentration of ammonia will also be recorded as well. The MC300can then reset the next maintenance countdown (step1123), including resetting the Next Maintenance display value (step1124), and enter into standby mode (step1125).

In an aspect, the ammonia monitoring system10can also have a calibration and diagnostic mode. The Calibration and Diagnostic mode facilitates calibrating the unit and performing certain diagnostics. In an aspect, the user can initiate the Calibration and Diagnostic mode by connecting a computer to an auxiliary data port58and running a calibration & diagnostic application from a computer. The application calibrates the chemical sensor by exposing the ammonia sensor to a test fixture containing known levels of ammonia mixed with air, as verified by a reliable, high-precision reference sensor. The calibration & diagnostic application may be configured to guide the operator through the calibration steps, and generate appropriate calibration coefficients, based on formulas and/or lookup tables. In an aspect, the calibration coefficients are stored locally on the ammonia sensor. In other aspects, the coefficients can also be stored in a global database.

The calibration & diagnostic application will also load identifying data into the local memory of the ammonia sensor20(discussed below), as well as the global database. Identifying data includes device hardware revision, firmware revision, serial number, date of manufacture, CSM200and waveguide230identifiers, with space reserved for user-defined data. Other identifying data may be included as well.

In an aspect, the calibration & diagnostic application can also have the ability to retrieve, store, and display real-time diagnostic data from the ammonia sensor20, to assist in troubleshooting and understanding behavior of the ammonia monitoring system10. Parameters may include, but are not limited to, pump current draw, total current draw, CSM current draw, CRC scan results, measurement history, system log, raw image data, and manual control of various subsystems.

In an aspect, a user can set options of the ammonia monitoring system10, and the ammonia sensor20. In an aspect, the user can set the options by selecting “Set Options” from the Main Menu to open a new menu with a number of options available to the user. These are specified in Table 3 below. The ‘min’ and ‘max’ refer to the highest and lowest levels of various components (e.g., ammonia coefficient, filter capacity, time, etc.) the user is allowed to select. In an aspect, the system10can be configured to have at least 5 ppm between “Caution” min and max, to prevent the user from setting thresholds that transition the system directly from “Normal” to “Warning”, with no “Caution” zone in between. While Table 3 shows number of options available to the user in the preferred embodiment of this invention, other embodiments may vary in the number and variability of the options.

As discussed above, the ammonia monitoring system10may be configured to communicate data from the ammonia sensor20to other devices. In an aspect, the ammonia sensor20can be configured to automatically transfer such information to a device through the auxiliary data port58. In an aspect, a program may guide the user through the process. To download data from the ammonia sensor20, the user can connect a device, including, but not limited to, a memory stick, to the auxiliary data port58and wait for a “data download complete” message on the user interface40before removing the device. Connection and data download can take place in any ammonia sensor mode, without interrupting the ammonia sensor measurements or other functions.

In an exemplary aspect, the device (e.g., a memory stick configured for connection with another computer or a computer itself) can include the program guide and be further configured to provide an interface to prompt the user to utilize the acquired data. For example, a simple interface will allow the user to: view date ranges available for download; select a date range and download the data as a comma separated text file, for import to a program such as Microsoft Excel or other spreadsheet applications; display the data graphically for a selected date range; and/or download a copy of the System Log as a text file. In an aspect, the device can be configured to communicate over a network, including, but not limited to, the internet. In such an aspect, the device, with user's permission, can connect to a designated website and check for available firmware upgrades. If one is available, the device can download the information for later uploading to the ammonia sensor20. If the ammonia sensor20is in measurement mode, the device can call upon the ammonia sensor to complete the present measurement and place the system10in Standby mode during upgrade, then automatically return the system to Measurement mode.

As discussed above, the MC300of the ammonia sensor20can maintain a system log for historical and diagnostic purposes according to an aspect. In such aspects, the system log shall be available for download as a text file, and can be viewable from the options screen. The system log can contain time-stamped records of all significant system events. The timestamp shall be independent of the user's clock setting. Examples of ‘significant system events’ are: Maintenance start/stop times; System Errors; Start/Stop Measurement Mode; User Data Downloads; Options Changes by User; and Power-ups.

The MC300of the ammonia sensor20is configured to handle exceptions and off-normal events during its operation. These events will not cause ammonia monitoring system10instability, hardware damage, or an unsafe situation. Exceptions are normally handled by error messaging prompting the user to take action.

As discussed above, the ammonia sensor20is typically mounted in a poultry house control room12b, adjacent to a house controller30, which regulates ventilation, light, heating, curtains, water sprinklers, food dispensers, and other systems in the poultry holding area12a, generally based on readings of temperature, humidity, and bird weight that the house controller30takes with its own sensor systems. Several controllers on the market (e.g., controllers supplied by ChoreTime Brock) already have an input for “ammonia level” built into them, but at present this input is unused. No industry standard exists as to data format for this input. Therefore, the communication connector54of the ammonia sensor20can be configured to conform to interface specifications defined by one or more of the controller vendors.

Embodiments of the ammonia sensor20may be designed for compatibility with the controller output interface, so that commands from the controller could potentially be received and managed. The following design “hooks” may be built into the hardware (i.e., MC300) of the ammonia sensor20: one or more Analog-to-Digital Converter ports going into the microprocessor; one or more dedicated SPI bidirectional interfaces; one or more dedicated12C bidirectional interfaces; Room for signal conditioning/amplifier circuitry; and microprocessor and memory overhead to manage the above items.

FIG. 15is a block diagram illustrating an exemplary operating environment for performing the disclosed methods above by the ammonia sensor20, and more specifically the MC300of the ammonia sensor20. This exemplary operating environment is only an example of an operating environment and is not intended to suggest any limitation as to the scope of use or functionality of operating environment architecture. Neither should the operating environment be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment.

Further, one skilled in the art will appreciate that the systems and methods disclosed herein can be implemented via the monitor controller (MC)1401illustrated inFIG. 13(the MC1401can be thought of as a general-purpose computing device like a computer board1401but contained within the ammonia sensor20). The components of the MC1401can comprise, but are not limited to, one or more processors or processing units1403, a system memory1412, and a system bus1413that couples various system components including the processor1403to the system memory1412. In the case of multiple processing units1403, the system can utilize parallel computing.

The system bus1413represents one or more of several possible types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, and a processor or local bus using any of a variety of bus architectures. By way of example, such architectures can comprise an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MCA) bus, an Enhanced ISA (EISA) bus, a Video Electronics Standards Association (VESA) local bus, an Accelerated Graphics Port (AGP) bus, and a Peripheral Component Interconnects (PCI), a PCI-Express bus, a Personal Computer Memory Card Industry Association (PCMCIA), Universal Serial Bus (USB) and the like. The bus1413, and all buses specified in this description can also be implemented over a wired or wireless network connection and each of the subsystems, including the processor1403, a mass storage device1404, an operating system1405, detection application1406, detection data1407(including the ammonia concentration amounts, thresholds, etc.), a network adapter1408, system memory1412, an Input/Output Interface1410, a display adapter1409, a display device1411, and a human machine interface1402.

The MC1401can comprise computer readable media. Exemplary readable media can be any available media that is accessible by the MC1401and comprises, for example and not meant to be limiting, both volatile and non-volatile media, removable and non-removable media. The system memory1412comprises computer readable media in the form of volatile memory, such as random access memory (RAM), and/or non-volatile memory, such as read only memory (ROM). The system memory1412typically contains data such as detection data1407and/or program modules such as operating system1405and detection application1406that are immediately accessible to and/or are presently operated on by the processing unit1403.

In another aspect, the MC1401can also comprise other removable/non-removable, volatile/non-volatile computer storage media. By way of example,FIG. 13illustrates a mass storage device1404which can provide non-volatile storage of computer code, computer readable instructions, data structures, program modules, and other data for the MC1401. For example and not meant to be limiting, a mass storage device1404can be a hard disk, a removable magnetic disk, a removable optical disk, magnetic cassettes or other magnetic storage devices, flash memory cards, CD-ROM, digital versatile disks (DVD) or other optical storage, random access memories (RAM), read only memories (ROM), electrically erasable programmable read-only memory (EEPROM), and the like.

Optionally, any number of program modules can be stored on the mass storage device1404, including by way of example, an operating system1405and detection application1406. Each of the operating system1405and the detection application1406(or some combination thereof) can comprise elements of the programming and the detection application1406. Detection data1407can also be stored on the mass storage device1404. Detection data1407can be stored in any of one or more databases known in the art. Examples of such databases comprise, DB2®, Microsoft® Access, Microsoft® SQL Server, Oracle®, mySQL, PostgreSQL, and the like. The databases can be centralized or distributed across multiple systems.

In another aspect, the user can enter commands and information into the ammonia sensor via the MC1401through the human machine interface1402. For example, the human machine interface can take the form of the interface40shown inFIG. 2. However, other input devices, including, but not limited to, a keyboard, mouse, and the like, can be used. These and other input devices can be connected to the processing unit1403via a human machine interface1402that is coupled to the system bus1413, but can be connected by other interface and bus structures, such as a parallel port, game port, an IEEE 1394 Port (also known as a Firewire port), a serial port, or a universal serial bus (USB).

In yet another aspect, a display device1411can also be connected to the system bus1413via an interface, such as a display adapter1409. In an aspect, the display device1411can be the interface40as shown inFIG. 2. In addition to the display device1411, other output peripheral devices can comprise components can be connected to the MC1401via Input/Output Interface1410(e.g, the external connectors50ofFIG. 2). Any step and/or result of the methods can be output in any form to an output device. Such output can be any form of visual representation, including, but not limited to, textual, graphical, animation, audio, tactile, and the like.

As discussed above, the MC1401can operate and control a fluid control system (FCS)1501and a chemical sensor module (CSM)1601. The MC1401can be connected to the FCS1501and CSM1601through various input/output interfaces1410.

For purposes of illustration, application programs and other executable program components such as the operating system1405are illustrated herein as discrete blocks, although it is recognized that such programs and components reside at various times in different storage components of the MC1401, and are executed by the data processor(s) of the MC1401. An implementation of the detection application1406can be stored on or transmitted across some form of computer readable media. Any of the disclosed methods can be performed by computer readable instructions embodied on computer readable media. The methods and systems can employ Artificial Intelligence techniques such as machine learning and iterative learning. Examples of such techniques include, but are not limited to, expert systems, case based reasoning, Bayesian networks, behavior based AI, neural networks, fuzzy systems, evolutionary computation (e.g. genetic algorithms), swarm intelligence (e.g. ant algorithms), and hybrid intelligent systems (e.g. Expert inference rules generated through a neural network or production rules from statistical learning).

While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. To the extent necessary to understand or complete the disclosure of the present invention, all publications, patents, and patent applications mentioned herein are expressly incorporated by reference therein to the same extent as though each were individually so incorporated.

Having thus described exemplary embodiments of the present invention, those skilled in the art will appreciate that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope of the present invention. Accordingly, the present invention is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims.