Patent Publication Number: US-2021187526-A1

Title: Portable low-pressure airless sprayer

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 62/952,817, filed on Dec. 23, 2019, the contents of which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     In a typical fluid spraying system, a fluid applicator is fluidically coupled to a source of fluid and is configured to apply the fluid to a surface. In some cases, the fluid includes substances composed of coloring matter or pigment. 
     The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background. 
     SUMMARY 
     A handheld portable spraying system includes a fluid source having a plurality of different fluids and a fluid container configured to separately contain the plurality of different fluids. The handheld portable spraying system also includes a fluid pathway configured to carry the plurality of different fluids from the fluid source through an outlet of the handheld portable spraying system, and a fluid conveyance system configured to cause the plurality of different fluids to flow along the fluid pathway. The handheld portable spraying system further includes a controller configured to generate a control signal to control the flow of the plurality of different fluids along the fluid pathway. 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, is not intended to describe each disclosed example or every implementation of the claimed subject matter and is not intended to be used as an aid in determining the scope of the claimed subject matter. Many other novel advantages, features, and relationships will become apparent as this description proceeds. The figures and the description that follow more particularly exemplify illustrative examples. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view showing one example of a spraying system. 
         FIG. 1B  is a block diagram showing one example of a spraying system. 
         FIG. 2  is a perspective view showing one example of a spraying system operated by a user. 
         FIG. 3  is a perspective view showing one example of a spraying system. 
         FIG. 4  is a perspective view showing one example of a spraying system. 
         FIG. 5  is a bottom-view showing one example of a spraying system. 
         FIGS. 6A-6C  are perspective views of examples of a housing. 
         FIG. 7  is a sectional view showing one example of a housing. 
         FIGS. 8A-8B  are diagrammatic views showing one example of a fluid pathway. 
         FIG. 9  is a perspective view showing one example of a computing device. 
         FIG. 10  is a perspective view showing one example of a mixing unit. 
         FIGS. 11A-11D  are illustrative examples of reference samples and/or surfaces. 
         FIGS. 12A-12C  are illustrative examples of user interface displays. 
         FIG. 13  is an illustrative example of a user interface display. 
         FIG. 14  is a perspective view showing one example of a spraying system. 
         FIG. 15  is a block diagram showing one example of a spraying system architecture. 
         FIG. 16  is a block diagram showing one example of a color matching system. 
         FIGS. 17-18  are flow diagrams showing example operations of a color matching system. 
         FIG. 19  is a block diagram showing the architecture illustrated in  FIG. 15  deployed in a remote server computing environment. 
         FIG. 20  is a block diagram showing one example of a computing environment that can be used in the architecture illustrated in previous FIGS. 
     
    
    
     While the above-identified figures set forth one or more examples of the disclosed subject matter, other examples are also contemplated, as noted in the disclosure. In all cases, this disclosure presents the disclosed subject matter by way of representation and not limitation. It should be understood that numerous other modifications and examples can be devised by those skilled in the art which fall within the scope and spirit of the principles of this disclosure. 
     DETAILED DESCRIPTION 
     There are a wide variety of fluid spraying systems. For example, a typical airless sprayer sprays fluid from a fluid source (e.g., 5-gallon paint bucket) at a very high pressure (e.g., up to approximately 3000 PSI), through a hose and out of a small opening or orifice in a spray gun tip. The tip is configured to break up the paint into a generally fan-shaped spray pattern of tiny droplets (e.g., atomization). In some airless sprayers, different tips can be used to accommodate different liquids, as well as to adjust the spray pattern, directionality, etc. To operate at the high pressure, some airless sprayer systems require a separate motor and pump assembly (usually carried on a cart) delivering pressurized fluid to the spray gun through a line extending from motor and pump assembly to a fitting on the gun. Additionally, the high pressure at which the fluid is pressurized requires that components of the spraying system be configured to withstand the high pressure, typically requiring more robust materials. While these high-pressure systems allow for a wide variety of fluids to be sprayed, the system requirements can add additional cost as well as limit the mobility of the system. Furthermore, the high pressure can increase material waste (such as from overspray) and can be difficult for a user to properly operate, particularly an inexperienced user. 
     Other types of spraying systems exist. For example, a high-volume low pressure (HVLP) spraying system generally seeks to reduce the drawbacks associated with a high-pressure spraying system by propelling fluid from a fluid source with a high volume of air at a lower pressure. This can reduce, for example, the amount of material waste, as well as the size and requirements for the system and can be easier for a user to operate. However, even for these HVLP systems, a separate assembly (e.g., an air compressor) is generally required which can add cost and limit portability. Furthermore, the materials must still be robust enough to handle the high volume of compressed air. These requirements can impose a cost that can be prohibitive to some users or for use in some fluid application operations. 
     Additionally, the fluid (e.g., paint) used in a high pressure and/or high-volume low-pressure system is typically pre-mixed (or pre-pigmented) off-site at, for example, various fluid vendors. The user can select from a variety of color options that the vendor offers, or in some cases, can bring in a sample color for the vendor to try and match. In any case, there is an added expense and inconvenience of having to leave the jobsite to resupply and/or go to a vendor ahead of time in preparation for a job. Additionally, once the fluid is mixed it is difficult to adjust the color, especially without additional expense and/or inconvenience. 
     Less expensive and more convenient (in some ways) alternatives exist. For example, spray paint cans (e.g., aerosol cans) can come in a variety of colors and are relatively inexpensive as compared to a can/bucket of paint. However, spray paint cans can release pollutants into the environment. Additionally, the pounds per square inch (PSI) output (e.g., approximately 100 PSI) of typical spray paint cans can be well below the required PSI output to spray (or spray desirably) higher quality paints (e.g., thicker paints) as well as certain other fluids. 
     In some examples described herein, a portable handheld airless spraying system operates at significantly lower pressures than typical airless spraying systems and with high atomization rates. In one example, the spraying system comprises a spray gun having an onboard fluid source that can be pressurized at an operating pressure suitable to spray a variety of fluids, including higher quality paints. In one example, the onboard fluid source can be pressurized at a pressure lower than typical airless sprayers (e.g., less than approximately 3000 PSI) and higher than typical aerosol spraying systems (e.g., more than approximately 100 PSI). In one example, the spraying system can pressurize the onboard fluid source at a range of 100 PSI to 1000 PSI. In one example, the fluid is pressurized by a liquified gas contained within a pressure vessel. For instance, but not limited to, a replaceable Carbon Dioxide (CO 2 ) cannister that applies pressure to a fluid container (e.g., a collapsible bag, bladder, etc.) at approximately 700-800 PSI. In some examples, the handheld spraying system is provided with an electronics assembly having, for example, but not limited to, processor(s)/controller(s), an interactive display (e.g., touchscreen) which can include a variety of user input mechanisms and/or display elements, as well as a variety of other items (e.g., sensors, various logic, and circuitry, etc.). The processor(s)/controller(s) and/or interactive display can, in some examples, allow a user to control, modify, adjust, etc. a variety of characteristics, parameters, etc. relative to the spraying system, for example, but not limited to, a ratio, flow rate, volume, etc. of fluid(s) from the fluid source, the operating pressure, etc. 
     Additionally, in further examples, the handheld spraying system includes a fluid source having multiple fluid compartments, the flow from which can be controlled (e.g., automatically by a control system, manually by a user, etc.) to desirably control a mixture of fluid to be sprayed by the spraying system. In some examples, the multiple fluid compartments are configured to contain different fluids (e.g., differently colored/pigmented paints). Further examples provide the handheld spraying system with a color matching system configured to match a preprogrammed, user selected, and/or automatically determined (e.g., via sensors and processing) color by controllably conveying fluid(s) from fluid source(s) to generate a desirably mixed fluid. In some examples, the color matching system includes a color sensor, which can be coupled to the handheld spraying system (e.g., electronically, physically, and/or communicatively, etc.) which can sense a surface and generate a sensor signal indicative of a color of the surface. The color matching system can include various logic which, based upon the sensor signal, can determine a color of the surface and generate control/action signals to components of the spraying system (e.g., metering elements [valves, pumps, etc.], a fluid conveyance system [e.g., motor(s), pump(s), pressure vessel(s), etc.], etc.) to, for example, control the flow of fluid(s) from fluid source(s) to, for example, but not limited to, generate a fluid having a mixture configured to replicate the determined color, as well as to generate a variety of displays, indications, recommendations, etc. on the user interface. 
       FIG. 1A  is a perspective view showing one example spraying system  100 . As illustrated, spraying system  100  is a handheld, portable spray gun, although in other examples, spraying system  100  can comprise any number of other spraying systems. Spraying system  100  includes housing  102 , housing cap  104 , handle  106 , trigger  108 , gun body  109 , spray tip  110 , outlet  111 , electronics assembly  112 , display  114 , actuators  116  and  118 , display elements  120  and  122 , grip portion  124 , alignment indicator  126 , fastener(s)  128 , input/output port  141 . 
     Housing  102  is configured to house various elements of spraying system  100  including, but not limited to, fluid source(s), fluid pathway(s), metering device(s), mixing chamber(s), fluid conveyance (e.g., motor(s), pump(s), pressure vessel(s)) various sensor(s), as well as a variety of other elements, as will be discussed further herein. For purposes of illustration, housing  102  will be discussed with regard to a fluid source, for example, containing fluid(s) and/or source(s) of fluid to be sprayed out of outlet  111 . Housing  102  can be removably coupled to spraying system  100 . For example, housing  102  can be removably coupled (e.g., threadably coupled) to housing cover  104 . Housing cover  104  can be coupled to the bottom-end of handle  106 . For example, but not by limitation, housing cover  104  can be fixably mounted to the bottom-end of handle  106  such that housing  102  can fasten or couple to housing cover  104  for installation of housing  102  onto spraying system  100 . In another example, housing cover  104  can have an opening configured to allow a portion of handle  106  therethrough such that housing  102  is coupled to handle  106  and installed on spraying system  100 . A proper alignment of handle  106  and housing  102  and/or housing cover  104  can be indicated by alignment indicator  126 , illustratively shown as an arrow. In any case, fluid, contained within housing  102 , is carried by a fluid pathway (upon actuation of trigger  108  for example) from housing  102 , through handle  106  and gun body  109  through spray tip  110  and out of outlet  111 . 
     Handle  106  can comprise a grip portion  124  that can comprise a different material than the remainder of handle  106  (or the rest of spraying system  100 ) and include surface geometry (e.g., ridges) such that it is easier for a user to operate spraying system  100 . For example, grip portion  124  can comprise a slip-resistant (e.g., “grippier”) material (e.g., rubber) and include surface geometry, such as ridges, such that a user&#39;s hand can more easily grasp and control spraying system  100 . Handle  106  can be fastened or otherwise coupled to gun body  109  by fasteners  128 , illustratively shown as a screw. Fasteners  128  can be recessed within the body of handle  106  to prevent tampering or loosening of fasteners  128  (e.g., by inadvertent contact with some object) and/or to prevent potentially dangerous contact with fasteners  128  (e.g., a user&#39;s hand being cut by screwhead). In some examples, handle  106  can also include a filter, fluid lines(s), metering device(s), mixing chamber(s), fluid conveyance (e.g., pressure vessel(s), motor(s), pump(s), etc.) as well as a variety of other components. 
     Gun body  109  can include internal mechanics (e.g., a valve) that are actuated by user actuation of trigger  108  such that fluid flows from housing  102  and out of outlet  111 . Spray tip  110  is coupled to an end of gun body  109  and is configured to control the flow or pattern of spray of fluid as it exits outlet  111 . Spray tip  110  can be adjustable such that the flow rate (e.g., volumetric flow rate) or spray pattern is adjustable. For example, a user can turn spray tip  110  in a clockwise or counterclockwise direction, as indicated by arrow  129 . Additionally, spray tip  110  can be replaced with a different type of tip for a different spray pattern or to accommodate a different fluid, for example. In some examples, gun body  109  can also include a filter, fluid line(s), metering device(s), mixing chamber(s), fluid conveyance (e.g., pressure vessel(s), motor(s), pump(s), etc.) as well as a variety of other components. 
     Electronics assembly  112  is coupled to spraying system  100 , for example, by fasteners  130  (illustratively shown in  FIG. 2  as a screw). Electronics assembly  112  can include a variety of components, including, but not limited to user interface(s) (e.g., display(s)), power source(s), controller(s)/processor(s), logic, circuitry, data stores (e.g., memory) as well as various other components. As shown in  FIG. 1 , electronics assembly  112  includes display  114 , illustratively shown as an interactive display (e.g., a touchscreen). Display  114  can include a number of user input mechanisms and/or display elements. For example, but not limited to, any number of user input mechanisms to allow a user to control, modify, adjust etc. various characteristics, parameters, etc. of spraying system  100  (e.g., flow of fluids, operating pressure, etc.) as well as to interact with electronics assembly  112  and/or spraying system  100 . Additionally, display  114  can include any number of display elements configured to display a variety of information, items, etc., for example, but not limited to, characteristics, parameters, etc. of spraying system  100  (e.g., operating pressure, battery life, remaining fluid, ratio, flow rate, volume, connectivity, etc.). Display  114  can include any number of other items as well. 
     As illustrated, display  114  includes user input mechanisms  116  and  118  and display elements  120 ,  122  and  123 . User input mechanisms  116  and  118 , illustratively shown as “+” and “−” buttons or other actuators, are user actuatable and configured to allow a user to, for example, adjust an operating parameter of spraying system  100 . As shown in  FIG. 1A , a corresponding display element  120  is displayed between each set of “+” “−” actuators  116  and  118 . As shown, display elements  120  are “0”, “3” and “1” respectively. Display element  122 , illustratively shown as a color circle, indicates a preprogrammed, determined, and/or user selected color of fluid to be sprayed by spraying system  100 . Display element  123 , can display a variety of information. For example, display element  123  can be a textual display that indicates what the sum total of group display elements  120  (e.g., mixture requirements [ratio, flow rate, volume, etc.]) should be for the preprogrammed, determined, and/or user selected color of fluid as indicated by display element  122 . 
     As an illustrative example, the color selected and/or sensed by spraying system  100  and indicated by display element  122  is a “lime-green”. Display  114  indicates that, for a red-yellow-blue color palette, lime green should be 0 parts red, 3 parts yellow and 1 part blue (as indicated by display elements  120 ). A user can adjust the input of each color via user input mechanisms  116  and  118  (the input corresponding to a ratio, flow rate, volume, etc. of each colored fluid respectively). In any case, fluid can be drawn from housing  102  according to the desired mixture of fluid as indicated by display elements  120 . It is to be understood that display  114  can include any number of display elements, user input mechanisms, as well as other items, including various menus and displays. 
     As shown in  FIG. 1A , spraying system  100  can include an input/output port  141  (e.g., a USB port) configured to allow communicative coupling between components of spraying system  100  (e.g., electronics assembly  112 , color sensor  150  shown below, etc.) and various devices (e.g., computing devices), as well as to allow power supply (e.g., charging) to various components of spraying system  100  (e.g. power source(s)  610 , electronics assembly  112 , color sensor  150 , fluid conveyance  608 , fluid assembly  175 , etc.). For example, a charger can be “hooked-up” to port  140  such that a power source (e.g., a rechargeable battery) of spraying system  100  and its various components can be charged/recharged. This power source can be configured to provide power to any and all of the components of spraying system  100 . In another example, input/output port  141  can be configured to receive a wired connection to a power source, for example a power cord configured to plug into an outlet. 
       FIG. 1B  is a simplified block diagram showing one example spraying system  100 . As illustrated in  FIG. 1B , spraying system  100  includes electronics assembly  112 , fluid pathway  175 , fluid conveyance system  608 , one or more processors or controllers  614 , and can include a variety of other items  616  as well. As shown in  FIG. 1B , processor(s)/controller(s) can be a component of electronics assembly  114  or can be remote from but coupled to electronics assembly  114 . For the sake of illustrative clarity, spraying system  100  has been simplified in  FIG. 1B . It should be understood that spraying system  100  can include any number of other items as will be discussed in more detail herein, for example with regard to  FIG. 15 . 
     In any case, fluid conveyance system  608  causes fluid to flow (or otherwise be conveyed) along fluid pathway  175  to be, for example, sprayed out of an outlet (e.g.,  111 ). Fluid conveyance system  608  can include a number of items configured to cause a fluid to flow (or otherwise be conveyed), including, but not limited to, pump(s), motor(s), pressure vessel(s) etc. In one example, fluid conveyance system  608  comprises a liquified gas contained within a pressure vessel that is configured to apply a pressure to a fluid and/or fluid source such that the fluid is conveyed along fluid pathway  175 . In one example, the pressure vessel provides a pressure of less than approximately 3000 PSI. In one example the pressure vessel provides a pressure between 100 and 1000 PSI. In one example, the pressure vessel comprises a replaceable CO 2  canister containing liquified CO 2  that provides pressure to a collapsible fluid container (e.g., bag/bladder, etc.) such that fluid within the container is pushed out (via compression of the container) of an outlet of the container and along fluid pathway  175 . In one example, the replaceable CO 2  cannister provides a pressure of approximately 700-800 PSI. Though any number of pressure sources providing pressure at any pressure range can be used. In some examples, fluid conveyance system  608  can be controllably operated by processor(s)/controller(s)  614 , for instance automatically (e.g., based on sensor signals, based on preprogrammed and/or other stored data, etc.), or based on a user input, for example on display  114 . Additionally, various characteristics, parameters, etc. relative to fluid conveyance system  608  (as well as spraying system  100  generally) can be displayed via display elements on display  114 . 
     Fluid is carried by fluid pathway  175  from a fluid source (e.g., compartments  154 , fluid containers  159 , etc.) through an outlet of spraying system  100  (e.g.,  111 ). Fluid pathway  175  can include a number of items, including, but not limited to, fluid source(s), fluid line(s), metering element(s), mixing chamber(s), as well as a variety of other items. In some examples, metering element(s) can comprise valve(s) (e.g., needle valves), pump(s) (e.g., peristaltic pumps) as well as a variety of other suitable metering element(s). In one example, metering element(s) can be controllably operated by processor(s)/controller(s)  614 , for instance automatically (e.g., based on sensor signals, based on preprogrammed and/or other stored data, etc.), or based on a user input, for example, on display  114 . For instance, but not limited to, controlling metering element(s) to control a ratio, flow rate, volume of fluids along fluid pathway  175 . Additionally, various characteristics, parameters, etc. relative to fluid pathway  175  (as well as spraying system  100  generally) can be displayed via display elements on display  114 . In some examples, various fluids (e.g., differently colored paints) are controllably conveyed (e.g., caused to flow) along fluid pathway  175  to mixing chamber(s) where the separately conveyed fluids are converged and configured to mix and are output, in some examples, from a single outflow (e.g., fluid line) from the mixing chamber(s) through the outlet of spraying system  100 . 
     It should be noted that these are merely examples of the items included in and operation of spraying system  100 . Spraying system  100  can include a variety of other items and be operated in a variety of other ways, including those described further herein. 
       FIG. 2  is a perspective view showing spraying system  100  operated by one example user  132 . As shown in  FIG. 2 , user  132  grips handle  106  with hand  134 . Trigger finger  136  of hand  134  is thus able to actuator trigger  108  to control the flow of fluid from housing  102  out of outlet  111 . 
       FIG. 3  is a perspective view of spraying system  100 . As shown in  FIG. 3 , display  114  includes user input mechanisms  116  and  118  and display elements  120  and  123 . A user (e.g.,  132 ) can actuate user input mechanisms  116  and  118  to adjust a variety of parameters and/or characteristics of spraying system  100  and/or the fluid to be sprayed. For example, the mixture of fluids (e.g., mixture of colors), the flow rate of each fluid, the brightness/darkness (e.g., hue) of the preprogrammed, determined, or selected color, as well as a variety of other characteristics and parameters. Display elements  120  can display a number or value corresponding to the fluids and/or colors. For example, the mixture of fluids (e.g., red, yellow, blue). The number or value can, in one example, correspond to a ratio, flow rate, or volume of each fluid to be mixed by spraying system  100 . 
       FIG. 4  is a perspective view of spraying system  100 . Electronics assembly  112  can include an input/output port (e.g., a USB port), such as input/output  140  (shown in  FIG. 4 ) and/or input/output port  142  (shown in  FIG. 5 ). In some examples, electronics assembly  112  can include both port  140  and port  142 . In other examples, electronics assembly  112  includes only one of port  140  or port  142 . Input/output ports  140  and/or  142  are configured to allow communicative coupling between electronics assembly  112  and various devices (e.g., computing devices), as well as to allow power supply (e.g., charging) to various components of electronics assembly  112 . For example, a charger can be “hooked-up” to port  140  and/or  142  such that a power source (e.g., rechargeable battery) within or coupled to electronics assembly  112  can be charged/recharged. In another example, input/output ports  140  and/or  142  can be configured to receive a wired connection to a power source, for example a power cord configured to plug into an outlet. 
       FIG. 5  is a bottom-view of spraying system  100 . As can be seen in  FIG. 5 , housing  102  has an opening  146  on its bottom side configured to allow access to as well as provide a viewing pathway for color sensor  150 . Color sensor  150  can be housed within housing  102 , and further within sensor housing  148 . Sensor housing  148  is configured to protect color sensor  150  (as well as components thereof) from contamination (e.g., dust, debris, fluid spray, etc.) and damage (e.g., contact with other elements of a worksite environment). Color sensor  150  is coupled to electronics assembly  112 . Color sensor  150  can comprise an optical and/or imaging sensor (e.g., a camera) configured to sense a characteristic of a color matching surface (e.g., a surface having a color to be matched) indicative of a color of that color matching surface. The color matching surface can include a variety of items, objects, and/or surfaces, for example, but not limited to, a color sample, a color swathe, a paint chip, a surface of a wall, etc., including any other item, object, or surface that color sensor  150  can view. In another example, color sensor  150  can comprise a spectrophotometer. Color sensor  150  can include a receiver and an illumination source that can project light onto the color matching surface. Color sensor  150  can include various other items as well, such as a one or more filters to filter out undesired light. 
     In one example operation of color sensor  150 , a user positions spraying system  100  such that color sensor  150  can scan and/or capture an image of a desired color matching surface. Housing  102  and opening  146  can provide a desirable imaging environment (e.g., lighting conditions) such that color sensor  150  can scan and/or capture an accurate image of the color matching surface. For example, housing  102  can block undesired light (e.g., ambient light) from being received by color sensor  150 . In one example, a user can place the bottom side of housing  102  over the color matching surface such that the color matching surface is in a field of view of color sensor  150  and scan and/or capture an image of the color matching surface with color sensor  150 . In one example, color sensor  150  can be operated via electronics assembly  112  (e.g., via a user input mechanism [e.g., a button] on screen  114 ) to, for example, scan and/or capture an image, adjust characteristics and/or parameters of color sensor  150  (e.g., lighting [e.g., flash], viewing angle, and various other imaging/optical system characteristics and/or parameters). Color sensor  150 , which can be pre-calibrated by the manufacturer, generates a sensor signal indicative of a color which is received by controller(s)/processor(s) of electronics assembly  112  to determine the color of the color matching surface. A control/action signal (or other output) can then be generated, based on the sensor signal, indicative of the sensed color. In one example, the sensed and determined/detected color can be displayed to the user on display  114 , for example as display element (e.g., a color circle)  122 . Further, in some examples, the required mixture of fluids for the sensed and/or determined/detected color can be indicated by display elements (e.g., numbers/values)  120 . In this way, spraying system  100  can be controlled to spray a fluid that comprises a mixture of fluids configured to replicate the color of the color matching surface. 
     In another example, color sensor  150  includes an illumination source (e.g., a flash element, white light generator, etc.) that is adjustable (e.g., brightness, on/off, etc.) via, for instance, a user input on display  114  or automatically via electronics assembly  112  (e.g., by a threshold [e.g., ambient light, brightness threshold]). In another example, the position of color sensor  150  is adjustable (e.g., viewing angle) via, for instance a user input on display  114  or automatically via electronics assembly (e.g., by a threshold [e.g., clarity threshold, quality threshold, position of color matching surface, etc.]). 
     In one example, color sensor  150  can be removable from spraying system  100 . As illustrated in  FIG. 5 , color sensor  150  can be retained within housing  102  by retaining device  147  which can be coupled and/or fastened to spraying system  100 . For example, retaining device  147  can include a surface having mating features (e.g., threads) configured to mate with mating features (e.g., threads) on an interior of housing  102  (e.g., on surface of wall defining opening  146 ). Retaining feature  102  can include features configured to make it easier for a user to install and uninstall retaining feature  147 . As illustrated, retaining feature  147  includes projections  149  which a user can, for example, grip or bear against to remove or couple retaining device  147  to spraying system  100 . In the case of threads, for example, projections  149  allow a user to more easily screw and unscrew retaining device  147 . 
     Color sensor  150  can be removed from housing  102 . For example, to allow a user to sense a color matching surface remotely from spraying system  100 . Color sensor  150  can maintain a communicative coupling with spraying system  100  even when removed from housing  102 , for example, color sensor  150  can maintain a wired connection with spraying system  100  (e.g., electronics assembly  112 ) or can maintain a wireless communicative coupling (e.g., Bluetooth) with spraying system  100  (e.g., electronics assembly  112 ). The removability allows, for example, a user to remove color sensor  150  from spraying system  100  during a spraying operation such that color sensor  150  is further protected from contaminants (e.g., dust, debris, liquid overspray, etc.). Additionally, the removal of color sensor  150  reduces the weight of spraying system  100  which can make it easier for the user to handle, for example, during a spraying operation. Further, the removability of color sensor  150  allows a user to scan and/or capture an image of a color matching surface without having to bring the entirety of spraying system  100  along. This can increase safety if the location of the color matching surface is in a difficult to reach location, or if, for example, a user has to climb a ladder to reach the color matching surface. Additionally, this can allow, for example, a tandem (e.g., a team) of workers at a worksite to split the operation of spraying system  100 . For example, one worker can take color sensor  150  to the location of the color matching surface (which can be remote from the surface that is to be sprayed) while the other worker can remain in the location of the surface to be sprayed. It is to be understood that these are merely examples of the advantages of a removable color sensor and that numerous other advantages are contemplated herein. 
       FIGS. 6A-6C  are perspective views of examples of housing  102 . Housing  102  includes lip  152 , compartments  154 , walls  156 , divider  158  and fluids  160 ,  162 ,  164 , and  166 . As illustrated in  FIG. 6 , the interior of housing  102  can be divided by divider  158  into separate compartments  154  defined by walls  156  of divider  158 . Each compartment  154  can hold a fluid (e.g., paint). As illustrated in  FIG. 6A , housing  102  may include four separate compartments  154 . Each of the four compartments  154  illustratively hold a different color paint, in this case Cyan  160 , Magenta  162 , Yellow  164  and Black  166  (collectively referred to as CMYK). As illustrated in  FIG. 6B , in another example, housing  102  may include three separate compartments  154 . Each of the three compartments  154  illustratively hold a different colored/pigmented paint, in this case, Red  168 , Yellow  170  and Blue  172  (collectively referred to as RYB). As illustrated in  FIG. 6C , in yet another example, housing  102  may include a single compartment  154  holding a single fluid  173 . For example, housing  102  (as shown in  FIG. 6C ) can be configured to hold a single fluid (e.g., a single colored/pigmented paint). In some examples, spraying system  100  can operate without color matching and allow the user to, for instance, interchangeably adjust the fluid(s) to be sprayed by spraying system  100  by changing the fluid within housing  102 , or attaching a new housing  102  having a different fluid. Additionally, even in examples of spraying system  100  having a multi-compartment housing  102  (e.g.,  FIGS. 6A and 6B ), color matching is not necessary. For example, a user (e.g., via display  114 ) can adjustably control the flow of fluids (as well as various other characteristics, parameters, etc.) without requiring color matching. 
     In other examples, housing  102  can have any number of compartments  154  containing any number of fluids (e.g., colored paints), and/or any number of compartments containing any number of fluids of various combinations, for example, multiple compartments of the same color fluid along with singular compartments of different colored fluids. Additionally, each of the separate compartments  154  can be configured to hold a separate type of fluid, for example, but not limited to, primer, paint, sealer, etc. 
     While illustrated examples are discussed above in the context of red-yellow-blue (RYB) and/or cyan-magenta-yellow-black (CMYK) color models, it is to be understood that a variety of other color models can be used, for example, but not limited to red-green-blue (RGB). Furthermore, a hue-saturation-value (HSV), sometimes called hue-saturation-brightness (HSB), model can be used wherein white and black are added to modify, for example, base colors generated by a variety of colors (e.g., RYB, CMYK, RGB, etc.). It should be understood that spraying system  100  can include any number of colored/pigmented fluids having any number and/or variety of colors/pigments. 
     Additionally, spraying system  100  and by extension housing  102  can include a number of sensors. For example, housing  102  (or spraying system  100 ) can include fluid level sensors that sense the amount of remaining fluid in housing  102  (e.g., the amount of fluid remaining in each of the compartments  154 ). Fluid level sensing can be done in a number of ways, including, but not limited to, ultrasound, pressure, etc. When the fluid from one or more compartments is running low a user may be notified. For example, an alert or other indication can be surfaced to a user interface, for example, display  114  (as well as various other displays on other machines, systems, devices, etc.), or a device (e.g., a handheld device, a computer, etc.). In some examples the device can be remote from spraying system  100  and communicated with over a network. 
     In any case, and as will be discussed in further detail below, spraying system  100  is configured to, in one example, pump or otherwise cause fluid from each of the compartments  154  to flow along a fluid pathway and out of outlet  111 . The ratio, volume and/or flow rate (e.g., volumetric flow rate) can be controlled by spraying system  100  and can be user adjustable, modifiable, etc. In another example, the color is modifiable (e.g., via a user input) and spraying system  100  (e.g., color matching system  624 ) automatically adjusts the mixture of fluids based on, for example, a user input. For the purpose of illustration, but not by limitation, in the example shown in  FIG. 1  with “lime green”, spraying system  100  can pump or otherwise cause fluid, according to the mixture requirements (e.g., “0” Red, “3” Yellow and “1” Blue), to flow from each of the compartments  154 . 
       FIG. 7  is a sectional view showing one example of housing  102 . Housing  102  includes lip  152 , compartments  154 , wall  156 , connection portion  157 , divider  158 , fluid containers  159 , red  168  and blue  172 . As illustrated in  FIG. 7 , housing  102  is a sectional view of housing  102  from  FIG. 6B  and illustrates a sectional view of compartments  154  that hold red  168  and blue  172 . As shown in  FIG. 7 , compartments  154  can include or comprise fluid containers  159 . In one example, fluid containers  159  comprise collapsible bladders/bags made of suitable material (e.g., polymer, rubber, etc.) that are configured to collapse as fluid is drawn from them (or gaseous pressure is applied to them) such that substantially all of the fluid can be drawn from fluid containers  159  and there is little to no remainder. In one example, and as will be explained in more detail below, the fluid in compartments  154  and/or in fluid containers  159  can be pressurized by mixing with and/or being exposed to a pressurizing fluid contained in a pressure vessel (shown below). In this way, spraying system  100  comprises an “airless” spraying system, such that none of the propellant leaves the outlet with the fluid to be sprayed (e.g., paint). In one example, the fluid in the pressure vessel is CO 2  (e.g., the pressure vessel comprises a replaceable CO 2  cannister). In one example, connection portion(s)  157  can connect with or otherwise be coupled to (e.g., fluidically coupled) to metering devices configured to control the flow of fluid from fluid containers  159 . 
       FIGS. 8A-8B  (collectively referred to as  FIG. 8 ) are diagrammatic views showing one example of fluid pathway  175 . Fluid pathway  175  includes compartments  154 , Cyan  160 , Magenta  162 , Yellow  164 , Black  166 , Red  168 , Yellow  170 , Blue  172 , other(s)  174 , metering element(s)  176 , fluid lines  178  and mixing chamber(s)  180 . The flow of fluid along fluid pathway  175  can be controlled by metering element(s)  176 . Metering element(s)  176 , can comprise a number of devices, including, but not limited to pumps (e.g., peristaltic pumps), valves (e.g., needles valves) as well as various other metering devices. Metering element(s)  176  can be controllable (e.g., programmatically, via circuitry [e.g., electronic signals from a sensor], etc.) and be configured to actuate based upon generated control/action signals from controller(s)/processor(s) (e.g., a control/action signal generator). For example, but not by limitation, upon color sensor  150  generating a sensor signal indicative of a sensed color of a color matching surface, controller(s)/processor(s) (e.g., within electronics assembly  112 ) can determine the color to be matched and generate control signals to fluid conveyance system  608  and/or metering element(s)  176  to control the flow (e.g., ratio, flow rate, volume etc.) of fluid from compartments  154  (as well as fluid containers  159 ) along fluid pathway  175 . In another example, spraying system  100  can include a motor configured to drive metering element(s)  176  (e.g., a pump) based on generated control signals to the motor. While multiple metering element(s)  176  are shown in  FIG. 7 , this need not be the case. A single metering element  176  can be used to control the flow from all of compartments  154 , for example, a metering valve manifold. 
     In any case, metering element(s)  176  control the flow of fluid from compartments  154 , which can include or comprise fluid containers  159 , along fluid pathway  175  through fluid lines  178 . Fluid lines  178  can comprise any number of materials or structures suitable for the carriage of fluid (e.g., polymer/rubber tubing, etc.). The metered fluid is optionally sent to mixing chamber(s)  180  such that the separate fluids drawn from compartments  154  are mixed before reaching spray tip  110  (and out of outlet  111 ) as indicated by arrow  181 . Mixing chamber(s)  180  can comprise a number of devices with various internal geometries. For example, the internal geometry of mixing chamber(s)  180  can comprise a series of progressive and/or regressive steps having varying diameters (e.g., a series of progressive and/or regressive diameters). In another example, mixing chamber(s)  180  can comprise a turbulation chamber. The internal geometry of mixing chamber(s)  180  can be such that it is configured to effectively mix separate fluids from compartments  154  and/or maintain desirable pressure in fluid lines  178 . As shown in  FIG. 8 , fluid pathway  175  can also include other  174  which can comprise any number of fluids, including fluids (e.g., paints) having different color/pigment than those listed. Additionally, compartments  154 , while shown with specific colors for purpose of illustration, can include any number of colors, any number of types of fluids (e.g., primer, paint, sealer, etc.), as well as any number of combinations thereof. For instance, compartments  154  can contain all of the same color, all of the same type of fluid. In another example, a number of compartments  154  can have the same color or type of fluid while another number of compartments  154  can have a different color or type of fluid. 
       FIG. 9  is a perspective view of one illustrative example of a computing device  200 . Device  200  includes display  202 , illustratively shown as an interactive touchscreen display, and can include icons, tiles or other user input mechanisms  204 . Mechanisms  204  can be used by a user (e.g., via user input, such as touch) to perform various functionalities with device  200 , for example, but not limited to, running applications. Device  200  can have various connections  206  to various networks and/or devices, including, but not limited to, cellular, Bluetooth, Wi-Fi, etc. In one example, device  200  can include one or more user input mechanisms  204  configured to cause device  200  to perform various functionalities relative to color matching (e.g., color sensing, fluid mixing, etc.), as well as other functionalities relative to spraying system  100 , or a mixing machine  300  (shown below). For example, device  200  can include color matching  624  as, for example, an application, represented by input mechanism  208 . 
     In one example, color matching application  208  can interact with a color sensor. For example, an imaging sensor (e.g., camera) on device  200 , as represented indicated by input mechanism  210  (which can comprise a camera application that allows a user (or color matching system  624 ) to access and control a camera associated with device  200 ). A user, using color matching application  208 , can, in one example, scan and/or capture an image of a color matching surface (e.g., paint chip, wall, etc.) indicative of a color of the color matching surface. Color matching application  208  can, based on the scan and/or captured image, determine a color of the color matching surface (e.g., via processor(s)/controller(s), logic, color matching system  624  described further below, etc.). Color matching application  208  can include and/or display various display elements and/or user input mechanisms. For example, color matching application  208  can include user input mechanisms (e.g., buttons, actuators, etc.) configured to allow a user to modify the brightness/darkness of the determined color, modify the mixture of fluids, as well as control, modify, change, etc. various other characteristics and/or parameters, including characteristics and/or parameters relative to a color of a fluid, fluid mixture, etc. Once a color is determined or selected (e.g., by the user) it can be communicated to spraying system  100  via, for example, communicative coupling (e.g., Bluetooth) between device  200  and spraying system  100  (e.g., electronic assembly  112 ). In another example, it can be communicated to mixing machine  300  via, for example communicative coupling (e.g., Bluetooth) between device  200  and mixing machine  300  (shown below). Based on the communication, spraying system  100  can be controlled to generate fluid relative to the determined or selected color, determined or selected fluid mixture, etc. Similarly, based on the communication, mixing machine  300  can be controlled to generate fluid relative to the determined or selected color, determined or selected fluid mixture, etc. The determined or selected colors can be, in one example, stored in various data stores, local to or remote from device  200  and/or the color matching application  208 . The colors can be stored automatically by, for instance, application  208  or manually by a user. 
     In another example, the color matching application  208  can include preset (e.g., preprogrammed) colors, selectable by a user, which can, in some examples, be modified by a user (e.g., brightness/darkness). In such an example, it is not necessary to first sense a color matching surface, though in some examples, sensing of the sprayed surface can be done to determine/detect quality characteristics and/or metrics relative to the sprayed fluid and/or operation of the spraying system. 
     Some applications, like Sherwin-Williams ColorSnap® Visualizer allow a user to preview a color on a surface, such as a wall in an image. In some examples, color matching application  208  can provide a display that demos a determined or selected color on a surface, such as a wall, that is imaged by an imaging sensor on device  200 . In this way, the user can preview a selected or determined color on a surface to be sprayed. In some examples, the user can simultaneously modify characteristics (e.g., hue, brightness, shade, color) of the color being demoed on the surface, and such modification will be dynamically represented in the display. The color matching application  208  can output values, such as a ratio, a mixture, a volume, or a flowrate, of the different colors (such as the different colors in spraying system  100  or mixing machine  300 ) needed to be mixed generate the color being displayed on the surface. In yet other examples, the imaging sensor on device  200  can be used to scan identifying information, such as a barcode or data matrix (e.g., QR code) corresponding to a paint color, such as identifying information on a paint can, a product brochure, a color, paint sample stickers, as well as any number of other items having identifying information that indicates a color of paint. Based on the scanned information, color matching application  208  can provide a display of the color corresponding to the color indicated by the identifying information, such as a display of the color on a surface imaged by the imaging sensor on device  200 , or a display of the color as a display element on device  200 , as well as output values, such as a ratio, a mixture, a volume, or a flowrate, of the different colors needed to be mixed to generate the color indicated by the identifying information. 
     While not shown in  FIG. 9 , it is to be understood that device  200  can include a variety of components, including, but not limited to various logic, circuitry, processor(s)/controller(s), data stores (e.g., memory, cloud, etc.), etc. 
       FIG. 10  is perspective view showing one example of a mixing machine  300 . Mixing machine  300  includes display  302 , housing  304 , docking station  306 , mixed fluid container  308  and compartments  154 . Mixing machine  300  can, in one example, mix a variety of fluids (e.g., colored/pigmented paints) from fluid compartments  154 , based on a variety of received inputs and/or control/action signals, and dispense the mixed fluids into mixed fluid container  308  (e.g., a paint bucket) to be used with a variety of spraying systems, including, but not limited to, spraying system  500  shown below. Mixing machine can, in one example, dispense the mixed fluids through an outlet (not shown). For example, mixing unit  300  can mix fluids from compartments  154  based on received sensor signals from a variety of sensor(s) (e.g.,  150 ,  210 ,  602  shown below, etc.) indicative of a color. Additionally, mixing unit  300  can mix fluids from compartments  154  based on control/action signals received from a variety of control systems (e.g.,  112 ,  208 ,  604  shown below, etc.). Furthermore, mixing unit  300  can mix fluids from compartments  154  based on user inputs on a number of displays including, but not limited to, displays  114 ,  202  and  302 . Display  302  is illustratively shown as an interactive touchscreen display that can include a number of display elements, user input mechanisms, as well as a variety of other items. In one example, a user can interact with display  302  to select and/or modify characteristics or parameters relative to fluid mixture or color, including, but not limited to, selecting a color stored in a data store associated with mixing unit  300  (e.g., preprogrammed and/or saved colors stored in memory). While in  FIG. 10 , compartments  154  are illustratively shown as comprising/including cyan  160  and magenta  162 , mixing unit  300  can include a variety of other colored/pigmented fluids (e.g., paint) as well as a variety of other types of fluids. 
     While not shown in  FIG. 10 , is to be understood that mixing unit  300  can include a variety of components, including, but not limited to various logic, circuitry, processor(s)/controller(s), data stores (e.g., memory, cloud, etc.), etc. 
       FIGS. 11A-11D  (collectively referred to as  FIG. 11 ) are illustrative examples of reference sample and/or surface  350  (hereinafter “reference  350 ”). Reference  350 , illustratively shaped as a handheld card (though it can be any number of shapes), includes a number of reference color(s)  352  on its surface. The reference color(s) each have a known color value, that is predefined, preset, programmed, stored, etc. (e.g., calibrated) or otherwise obtained by color matching  624 . For example, a portion (including the entire surface) of reference  350  can comprise a single reference color  352  (as illustrated in  FIG. 11A ). In another example, a number of portions of a surface of reference  350  can include a number of reference color(s) (as illustrated in  FIGS. 11B-11D ). For example, reference  350  can include red, yellow, and blue reference color(s)  352  (as illustrated in  FIG. 11B ). In another example, reference  350  can include cyan, magenta, yellow, and black reference color(s)  352  (as illustrated in  FIG. 11C ). In yet another example, reference  350  can include any number of different reference color(s)  350  (as illustrated in  FIG. 11D ). While a particular size of reference color(s)  350  is shown in  FIG. 11 , it is to be understood that reference color(s)  350  can cover a variety of surface area(s) of reference  350 . 
     In any case, the known color values of reference  350  allows a user to calibrate color sensor(s) and/or color matching  624  (including preset, preprogrammed, or otherwise stored color(s) and fluid mixture(s) in memory [e.g., data store(s)]). In one example, calibrating includes compensating for environmental factors of the location in which the image is scanned and/or captured by the color sensor(s), for example, but not limited to, compensating for the effect(s) of lighting condition(s), viewing angle, reflectance (e.g., specular, diffuse, etc.), as well as any other factors which can affect image quality (e.g., accuracy). 
     In one example, a user holds (or otherwise places) reference  350  proximate to the color matching surface (e.g., the surface to be matched), such that both reference  350  and color matching surface are within the field of view of the color sensor(s) (e.g.,  150 ,  210 , etc.), and scans and/or captures an image. Reference  350  has reference color(s)  352  with predefined, preset, preprogrammed, etc. (e.g., calibrated) color values. Color matching  624  can, based on the scanned or captured image, determine the difference (e.g., offset) of the color values indicated by the image relative to the known color values of the reference color(s)  352  and compensate the color values of the color matching surface to be matched based on the determined difference. In this way, the color to be matched can be compensated for environmental factors. For illustrative example, but not by limitation, reference colors  352  can comprise the color red with color values known to color matching  624  (e.g., predefined, preset, preprogrammed, etc. [e.g., saved in memory and accessible]). A user can hold (or otherwise place) the red reference color next to the color matching surface (e.g., a brown wall) and scan and/or capture an image with color sensor(s). Because of, for example, the lighting conditions at the worksite, the known reference color red can appear, in the image, as “light-red” for instance, and the brown wall can appear in the image as “light-brown.” However, because the red reference color has color value(s) known to color matching  624 , color matching  624  can determine a difference between the color value(s) of the red (i.e., light red) in the image to the known color value(s) for the red reference color  352 . Based on this determined difference, color matching  624  can compensate the color value(s) of the brown (i.e., light-brown) in the image such that the environmental factors (e.g., lighting) are compensated for (e.g., effectively filtered out) and color matching  624  can control spraying system  100 , mixing machine  300 , etc., to generate a fluid having a color more accurately representative of the actual color of the color matching surface (e.g., wall), in this particular example, the generated fluid can be closer to the brown of the wall rather than the light-brown of the image. 
     Color matching system  624  can determine colors, mixtures of fluids, as well as various other characteristics in a number of ways. Generally, the color sensor receives illumination reflected from a color matching surface and based on the received illumination, determines a color of the color matching surface. For example, a color sensor (e.g.,  150 ,  210 , etc.) can comprise an imaging or optical device that scans and/or captures an image of a surface to be matched. In one example, the scan or image can be compared to preset, predefined, preprogrammed, etc. colors stored in memory (e.g., a data store). These stored colors can have known color values, for example, but not limited to, known fluid mixtures required to produce those colors (e.g., ratios of red-yellow-blue, cyan-magenta-yellow-black, as well as ratios of a variety of other color combinations). Based on the comparison, color matching system  624  can determine a color of the color matching surface and generate an output based on the determination (e.g., control/action signals based on the determination). In another example, color matching system  624  can perform analysis of the scan and/or image and obtain color data, such as red-yellow-blue (RYB) color data, cyan-magenta-yellow-black (CMYK) color data, red-green-blue (RGB) color data, as well as hue-saturation-value (HSV), also sometimes referred to as hue-saturation-brightness (HSB), color data. Based on the obtained color data, color matching system  624  can determine various characteristics and/or parameters relative to color and/or fluid mixture, for example, but not limited to color values, fluid mixture requirements (e.g., ratio, flow rate, volume, etc.) and based on those determinations, control, for example, spraying system  100 , mixing machine  300 , to generate a fluid (e.g., mix a fluid) having a color that matches and/or approximately matches the sensed color matching surface. 
     In one example, the color sensor can comprise an illumination detector and an illumination source. The illumination source projects light onto a color matching surface and the illumination detector detects light reflected from the color matching surface and based on the detected light, a color of the color matching surface can be determined. In one example, the color can be determined electronically (e.g., a spectrophotometer), for example, using a light-to-voltage converter in the sensor that causes the color sensor to respond to the reflected light by generating a voltage proportional to the color. The illumination source can include, for example, a white light generator, a flash feature on a camera, as well as a number of other illumination sources. In some examples, only the ambient light is used, and the effects of the ambient light can be compensated for if necessary. The color sensor can also include various filters, for example, filters that are configured to filter out undesired light (e.g., undesired wavelengths). The filters can have wavelength sensitivities at various lengths (e.g., various nanometer sensitivities). 
       FIGS. 12A-12C  are illustrative examples of user interface displays that can be displayed on various devices.  FIGS. 12A-12C  (collectively referred to as  FIG. 12 ) are illustrative examples of user interfaces that can be generated on a display (e.g.,  114 ,  202 ,  302 ). User interface  402  can comprise a “main menu” having selection mechanisms  404  that are user interactable/selectable and correspond with, in one example, a respective color space, for example, red-yellow-blue (RYB) as indicated by  406 , cyan-magenta-yellow-black (CYMK) as indicated by  408 , as well as a variety of other color space combinations. Upon user selection of the RYB or CYMNK color space  406  or  408 , user interfaces  410  or  411  can be displayed which include display elements  412 , which, as illustrated, can correspond to a particular color, as well as include value display elements  414 , which, as illustrated, can correspond to a value/metric associated with a particular color, for example a flow rate or volume of a particular color. In one example, value display elements  414  are automatically populated based on a color sensed by, for example, sensors  150  and/or  210 . Interfaces  410  or  411  can further include actuators  416  (represented by arrows) which are user interactable/selectable to, for example, adjust the value/metric associated with a particular color displayed by value display elements  414 . Interfaces  410  or  411  can also include a search element  418 , interactable/selectable by a user, to, for example, search for a stored (e.g., in a data store) color, which when found, can be displayed in display element  420  as, for example, a textual representation of the color (e.g., “LIME GREEN”). 
       FIG. 13  is an illustrative example of a user interface  450  that can be generated on a display (e.g.,  114 ,  202 ,  302 ). User interface  450  can comprise a “main menu” having a number of user input mechanisms  452  that are user interactable/selectable and correspond with, in one example, a respective color. In one example, user interface  450  allows a user to select from a number of preprogrammed and/or saved colors with a corresponding mixture (e.g., ratio, flow rater, volume, etc.). In another example, upon selection of one of user input mechanisms  452 , another user interface is displayed which can include a variety of display elements, user input mechanisms, etc., which can, in some examples, be used by the user to modify a parameter or characteristic relative to fluid mixture or color (e.g., brightness/darkness). In one example, upon selection of a color, a user can be directed to a user interface that allows the user to select from a range of shades (e.g., gradient) corresponding to the selected color. Similarly, in combination with or alternatively, user interface  450  can display a color gradient that is user interactable/selectable to select a color. 
       FIG. 14  is a perspective view showing one example spraying system  500 . Spraying system  500  includes pump  502  that is mounted on a cart  504  and couples to applicator  510  through delivery line  506 . Pump  502  includes a fluid intake  508  that is disposed within a fluid source (e.g., a five-gallon bucket of paint [e.g., mixed fluid container  308 ]). Pump  502  pumps the fluid from the fluid source through fluid intake  508  and pumps the fluid at a given pressure to applicator  510  through delivery line  506 . Mounted on or otherwise coupled to fluid intake  508  are fluid level sensor(s)  512  that can sense the amount of remaining fluid in the fluid source (e.g., via ultrasound, pressure, etc.). When the fluid is running low, a user can be notified. For example, surfacing an indication (e.g., alert, notification, message, display, etc.) on a display. Fluid level sensor  512  can also track usage over time and notify a user at given intervals, or store values indicative of usage in a data store. For example, a user may want to be notified when they have three-quarters remaining, one-half remaining, one-quarter remaining, etc. This may be useful in helping a user maintain an even coat of fluid coverage over a large spraying job. 
     Fluid applicator  510  (e.g., spray gun) receives fluid through an inlet  514  from delivery line  506 . Trigger  516  actuates to allow fluid flow from inlet  514  to an outlet  520  of tip  518  where the fluid is expelled. Tip  518  can be replaced with a different type of tip for a different spray pattern or to accommodate a different fluid. While fluid applicator  510  is shown in  FIG. 14 , various other fluid applicators can be used in combination with the architectures shown herein, including, but not limited to, spraying system  100 . For example, spraying system  100 . 
       FIG. 15  illustrates one example of a spraying system architecture  600  having a spraying system  100  configured to perform a spraying operation. Examples of spraying system  100  include, but are not limited to, spraying system  100  illustrated in  FIGS. 1-8 . Spraying system  100  can be communicatively coupled to computing device  200  and/or mixing machine  300  via various connections (e.g., Bluetooth) over network  644 . Additionally, user  650  can interact with or otherwise operate spraying system  100 , computing device  200  and/or mixing machine  300 . 
     Spraying system  100  includes housing  102 , housing cover  104 , handle  106  (which can include grip portion  124 ), trigger  108 , gun body  109 , spray tip  110 , outlet  111 , electronics assembly  112 , fluid pathway  175 , sensor(s)  602 , control system  604 , data store  606 , fluid conveyance system  608 , power source(s)  610 , input/output ports  611 , communication system  612 , processor(s)/controller(s)  614 , and other items  616  as well. Electronics assembly  112  includes display  114 , user input mechanism(s)  646  (e.g.,  116  and  118 ), display element(s)  648  (e.g.,  120 ,  122 ,  123 ) and can include other items  649  as well. 
     Display  114  is, in one example, an interactive touchscreen display having user input mechanism(s)  646  configured to allow intractability with user  650  to control or modify various characteristics and/or parameters relative to spraying system  100  as well as display element(s)  648  configured to display various information relative to spraying system  100 . Display  114  can, via display elements  648 , display a variety of characteristics, parameters, data, etc. of spraying system  100 , for example, but not limited to, battery life, amount of fluid remaining, amount of fluid used in current operation (or per operation, or over life-time, etc.), flow rate, current mixture, as well as a variety of other information relative to spraying system  100 , including any and all characteristics sensed by sensor(s)  602  and/or determined by control system  604 . 
     Fluid pathway  175  includes compartments  154  (which may include or comprise fluid containers  159 ), metering element(s)  176 , fluid lines  178 , mixing chambers(s)  180 , fluids  662  (which may include fluids of a variety of colors, including those described herein, and/or a variety of fluid types) and can include other items  664  as well. 
     Control system  604  is configured to control other components and systems of spraying system  100  as well as computing device  200  and mixing machine  300 . For instance, control system  604  includes a communication controller  626  configured to control communication system  612  to communicate between components of spraying system  100  and/or with other systems, machines, devices, etc. (e.g., computing device  200 , mixing machine  300 , etc.) over a network  644 . Network  644  can be any of a wide variety of different types of networks such as the Internet, a cellular network, Bluetooth, a wide area network (WAN), a local area network (LAN), a near-field communication network, or any of a wide variety of other networks or combinations of networks or communication systems. 
     Communication system  612  can include wireless communication logic, which can be substantially any wireless communication system that can be used by the systems and components of spraying system  100  to communicate information to other items, such as between control system  604 , sensor(s)  602 , electronics assembly  112 , fluid pathway  175 , fluid conveyance system  608 , and data store  606 . This information can include the various sensor signals and output signals generated by the sensor characteristics and/or sensed characteristics. 
     Sensor(s)  602  can include any number of different types of sensors that sense or otherwise detect any number of characteristics. In the illustrated example, sensor(s)  602  include color sensor(s)  618 , fluid level sensor(s)  620  and can include other sensor(s)  622  as well. Color sensor(s)  618  are configured to sense a color matching surface and generate a sensor signal indicative of a color of the color matching surface. Color sensor(s)  618  can include, but are not limited to, a variety of optical or imaging sensors (e.g., camera(s), receiver and illumination source, spectrophotometer, etc.), as well as color sensor(s)  150  and  210 . Fluid level sensor(s)  620  are configured to sense a level of fluid in a fluid source (e.g., level and/or volume of remaining fluid) such as compartments  154 , fluid containers  159 , as well as a variety of other fluid sources, and generate a sensor signal indicative of the remaining fluid in the fluid source(s). Other sensor(s)  622  can include any number of sensors. For example, positional sensors configured to sense a position of spraying system  100 , for instance, the position relative to or a distance from a surface to be sprayed, for example, but not limited to, a time of flight camera or a laser-based distance sensor configured to sense a distance of spraying system  100  from an object (e.g., wall to be sprayed, color matching surface, etc.). Other sensor(s)  622  can include orientation sensors, to sense, for instance, the tilt of spraying system  100 . Other sensor(s)  622  can include pressure sensor(s) configured to sense a pressure within, for example, fluid lines  178 , compartments  154 , fluid containers  159 , pressure vessel(s)  640 , etc. Other sensor(s)  622  can include flow sensor(s) configured to sense a flow rate of fluid through fluid pathways  175 , for instance. 
     Control system  604  is configured to control various characteristics and/or parameters of spraying system  100 , computing device  200 , mixing machine  300  including systems and elements thereof. Control system  604  receives or otherwise accesses sensor signals from sensor(s)  602  to determine a number of characteristics and generate a number of action/control signals based thereupon. Control system  604  includes color matching system  624 , communication controller  626  and can include other items  628  as well. Color matching system  624 , which will be discussed in more detail below, is generally configured to determine colors (e.g., sensed by sensor(s)  602 , selected by user  650 , etc.) and generate control/action signals to various components of architecture  600  to mix fluids based on the determined colors. Other items  628  can include various other systems, circuitry, logic as well as a variety of other items. Additionally, based upon received or accessed sensor signals from sensor(s)  602 , control system  604  can generate control/action signals to surface a variety of displays, recommendations or other indications (e.g., alerts) on, for instance, a variety of displays (e.g.,  114 ,  202 ,  302 ). 
     In one example, based on a sensor signal indicative of the position of spraying system  100  relative to a surface to be sprayed (e.g., a wall), control system  604  can control display  114  to surface an indication indicative of the distance. For example, but not limited to, activating display element(s)  648  to indicate the distance. For instance, a red light to indicate that the distance is sub-optimal (e.g., too far from or too close to the surface to be sprayed), or a green light to indicate that the distance is optimal (e.g., optimal spraying distance to/from surface to be sprayed, such as for optimal spraying coverage). Similarly, based on a sensor signal indicative of the orientation (e.g., tilt) of spraying system  100 , control system  604  can control display to surface an indication indicative of the orientation. For example, but not limited to, activating display element(s)  648  to indicate the orientation. For instance, a red light to indicate that the orientation is sub-optimal, or a green light to indicate that the orientation is optimal. Similarly, display element(s)  648  can comprise a scale (e.g., a red-to-green progressive/regressive scale) indicative of a current level of optimality of the position and/or orientation of spraying system  100 . 
     Spraying system  100  includes a data store  606  configured to store data for use by spraying system  100 , computing device  200  and/or mixing machine  300 , such as color data  630 , which can include a variety of data relative to various colors (e.g., sensed colors, user selected/modified colors, preprogrammed colors, etc.), mixture data, which can include a variety of data relative to fluid mixture requirements (e.g., ratio of fluid, flow rate, volume, etc.) for various colors, as well as various other data  634 . 
     Fluid conveyance system  608  is a controllable subsystem configured to convey fluid from fluid sources along fluid pathways. Fluid conveyance system  608  include motor(s)  636 , pump(s)  638 , pressure vessel(s)  640  and other items  642  as well. In one example, fluid conveyance system  608  includes a battery-powered motor  636  (e.g., powered by power source(s)  610 , such as a rechargeable battery) that drives a pump  638  (e.g., a gear pump) to controllably convey fluid from fluid sources. In another example, fluid conveyance system  608  includes a pressure vessel  640  that contains a pressurized or liquified gas used to pressurize the fluid in compartments  154  and/or fluid containers  159 . In one example, pressure vessel  640  comprises a CO 2  cartridge with liquified CO 2 , which can apply a pressure of around 700-800 PSI to a fluid source. When trigger  108  is actuated by user  650 , the liquified CO 2  is expanded into, for example, compartments  154  and/or fluid containers  159 , and it evaporates, creating a gaseous pressure. In one example, it creates a gaseous pressure of 700-800 PSI. In another example, fluid container  159  comprises a compressible bladder/bag that has a connection portion  157  that connects or otherwise couples (e.g., fluidically couples) to metering element(s)  176 , for instance a valve. CO 2  can thus be released into compartments  154  and the gaseous pressure compresses the compressible bladder/bag in order to convey fluid along fluid pathway  175  (e.g., upon actuation of trigger  108 ). It should be understood various other pressurized or liquified gases can be used which can apply pressure of various PSI ranges. 
     Fluid conveyance system  608  can be coupled to and/or disposed within spraying system  100 , as well as other systems, devices and/or machines (e.g., mixing machine  300 ). For example, but not limited to, a CO 2  cartridge coupled (e.g., fluidically) to compartments  154  and/or fluid containers  159  (e.g., via suitable fluidic pathways [e.g., valves, lines, conduits, tubing, etc.]) and can be disposed within spraying system  100 , for example, within handle  106 , housing  102  and various other locations. 
     Power source(s)  610  are configured to provide power to components of spraying system  100 , computing device  200 , and/or mixing machine  300 . Power source(s)  610  can comprise any number of power sources, including, but not limited to, batteries, rechargeable batteries, wired connections (e.g., power cord configured to plug into an outlet), as well as a variety of other power source(s). In one example, power source(s)  610  comprise a rechargeable battery that can be recharged via input/output ports  611  (e.g.,  140 ,  141 ,  142 ) which may comprise, for example, USB ports (e.g., micro-USB ports). In another example, power source(s)  610  comprise a rechargeable battery that is removably coupled to spraying system  100 . 
     Processor(s)/controller(s)  614  allow for the control of spraying system  100 , computing device  200  and/or mixing machine  300  and can be utilized by various elements of architecture  600 , including, but not limited to, control system  604 . Similarly, the various logic of architecture  600  can be embodied within or executed by processor(s)/controller(s)  614 . 
     A user  650  is shown interacting with computing device  200  and mixing machine  300  (as well as spraying system  100 ). Computing device  200  can include any number of computing devices (e.g., a mobile device, a tablet, a computer, etc.) including computing device  200  illustrated in  FIG. 9 . Computing device  200  includes display  202 , power source(s)  610 , and can include other items  660  as well. Computing device  200  can also optionally include (as represented by the dashed lines) sensor(s)  602 , control system  604 , data store  606 , and processor(s)/controller(s)  614 . For example, computing device  200  can include control system  604  which can include some or all of the components of control system  604 , as discussed with reference to spraying system  100 , for instance, color matching  624 . Display  202  includes user input mechanisms  204  and display elements  658  that can display any number of characteristics, parameters, data, and/or other information relative to computing device  200  and/or architecture  600 , including, but not limited to, characteristics sensed by sensor(s)  602  and/or determinations by control system  604 . 
     Mixing machine  300  can include any number of devices configured to mix fluids including mixing machine  300  illustrated in  FIG. 10 . Mixing machine  300  includes fluid pathway  175 , display  302 , fluid conveyance system  608 , power source(s)  610 , and can include other items  656  as well. Mixing machine  300  can also optionally include (as represented by the dashed lines) sensor(s)  602 , control system  604 , data store  606 , and processor(s)/controller(s)  614 . For example, computing device  200  can include control system  604  which can include some or all of the components of control system  604 , as discussed with reference to spraying system  100 , for instance, color matching  624 . Display  302  includes user input mechanism(s)  652  configured to allow user interaction with and/or control of mixing machine  300  and display element(s)  654  configured to display any number of characteristics, parameters, data, and/or other information relative to mixing machine  300  and/or architecture  600 , including, but not limited to, characteristics sensed by sensor(s)  602  and/or determinations by control system  604 . 
       FIG. 16  is a block diagram illustrating one example of color matching system  624 . Color matching system  624  includes communication system  612 , processor(s)/controller(s)  614 , color determination system  700 , fluid mixture system  702 , data capture logic  704 , quality determination system  705 , alert/notification system  708 , control/action signal generator  710 , and can include other items  726  as well. Color matching system  624  is configured to determine a color of a fluid to be sprayed, determine the required fluid mixture required to generate a fluid having the determined color, determine a quality of the fluid sprayed based on a comparison of the fluid sprayed to the determined color, as well as a variety of other functionalities. Color matching system  624  is further configured to, based on the various determinations, generate action/control signals to, for instance, control the operation of spraying system  100 , computing device  200  and/or mixing machine  300  or to generate displays, recommendations, and/or other indications (e.g., an alert). 
     Data capture logic  704  includes sensor accessing logic  720 , data store accessing logic  722 , and other logic  724 . Sensor accessing logic  720  can be used to obtain sensor data (or values indicative of the sensed variables) provided from sensor(s)  602  that can be used for a number of determinations including, but not limited to, determining a color of a color matching surface, determining requirements for fluid mixture to generate fluid having a particular color, determining a quality of a color of fluid sprayed, as well as a variety of other determinations. 
     Data store accessing logic  722  can be used to obtain stored data from a data store (e.g.,  606 ) for a number of determinations including, but not limited to, determining a color of a color matching surface, determining requirements for fluid mixture to generate fluid having a particular color, determining a quality of a color of fluid sprayed, as well as a variety of other determinations. 
     Upon receiving sensor data or indications of the sensed characteristics, as well as various other data, including data from a data store, color determination system  700  can determine a color for a fluid to be sprayed. This can include, for example, color recognition logic  712  determining a color of a color matching surface sensed by a color sensor (e.g.,  150 ,  210 ) and/or determining a color based on a user input (e.g., user selection of preprogrammed colors, user modification of color, etc.). Various other types of determinations relative to color of a fluid to be sprayed can also be made by other logic  714 . 
     Based on the various determinations, color determination system  700  can, for example, generate various recommendations/indications via alert/notification system  708  (e.g., surfacing a display to displays via display elements). Additionally, color determination system can generate various control/action signals via control/action signal generator  710  to control spraying system  100 , computing device  200 , and/or mixing machine  300 . Additionally, color determination system  700  can communicate, via communication system  612 , the determinations to various other components of architecture  600  (e.g., fluid mixture system  702 ). 
     Upon receiving sensor data or indications of the sensed characteristics, various other data from a data store, as well as communications from, for example, color determination system  700 , fluid mixture system  702  can determine fluid mixture requirements for a fluid to be sprayed. This can include, for example, fluid mixture logic  716  determining a ratio, flow rate, volume, etc. of fluid from fluid sources (e.g., compartments  154 , containers  159 ). Various other types of determinations relative to mixture requirements of a fluid to be sprayed can also be made by other logic  718 . 
     Based on the various determinations, fluid mixture system can, for example, generate various recommendations/indications via alert/notification system  708  (e.g., surfacing a display via display elements). Additionally, fluid mixture system  702  can generate various control signals via control/action signal generator  710  to control spraying system  100 , computing device  200  and/or mixing machine  300 . Additionally, fluid mixture system  702  can communicate, via communication system  612 , the determinations to various other components of architecture  600 . 
     As illustrated in  FIG. 16 , color matching system  624  includes quality determination system  705 . Upon receiving data or indications of the sensed characteristics, various other data from a data store, as well as communications from, for example, color determination system  700  and/or fluid mixture system  702 , quality determination system  705  can determine various quality metrics relative to spraying system  100 , computing device  200  and/or mixing machine  300 . For example, upon receiving sensor data from a color sensor indicative of a color of substance sprayed onto a surface, quality logic  706  can determine a quality of the fluid sprayed based on, for example, a comparison of the color of the fluid sprayed to a comparison of the determined color. In another example, upon receiving sensor data from a flow sensor, for example, quality logic  706  can determine a quality of the operation of fluid pathway  175  based on, for example, a comparison of the required mixture determination. Various other types of determinations of quality metrics relative to spraying system  100 , computing device  200  and/or mixing machine  300  can be made by other logic  707 . 
     Based on the various determinations, quality determination system  705  can, for example, generate various recommendations/indications via alert/notification system  708  (e.g., surfacing a display via display elements). Additionally, quality determination system  705  can generate various control signals via control/action signal generator  710  to control spraying system  100 , computing device  200  and/or mixing machine  300 . Additionally, quality determination system  705  can communicate, via communication system  612 , the determinations to various other components of architecture  600 . 
       FIGS. 17-18  are flow diagrams showing example operations of a color matching system  624  illustrated in  FIG. 16 . The operation shown in  FIG. 17  is one example of the operation of the system shown in  FIG. 16  in determining characteristics relative to a fluid to be sprayed. It is to be understood that the operation can be carried out at any time or at any point throughout a spraying operation, or even if a spraying operation is not currently underway. Further, while the operation will be described in accordance with architecture  600  (e.g., spraying system  100 , computing device  200 , and/or mixing machine  300 ), it is to be understood that other architectures, systems, devices, machines, etc. with a color matching system  624  can be used as well. 
     Operation  800  begins at block  802  where data is obtained (e.g., received, accessed, etc.) by color matching system  624 . Data (e.g., sensor data and/or values indicative of sensed variables, etc.) can be obtained from sensor(s)  602  as indicated by block  804 . However, data can also be obtained from a variety of other sensors of other systems. Sensor data can include, for example, sensor data indicative of a color of a color matching surface. For instance, a captured image of a color matching surface by a color sensor, for example, a camera or other imaging/optical sensor, and/or color sensors  150  and/or  210 . Data can be obtained from data store  606  as indicated by block  806 . However, data can also be obtained from a variety of other data stores of other systems. Data from a data store can include, for example, determined and/or preprogrammed fluid colors, determined and/or preprogrammed fluid mixture requirements, saved user inputs, as well as a variety of other data in a data store relative to characteristics of a fluid to be sprayed. Data can also be obtained from a variety of other sources as indicated by block  808 . Other data  808  can include, but is not limited to, user inputs indicative of a color and/or a mixture of a fluid to be sprayed. 
     Upon obtaining data, processing turns to block  810  where characteristics relative to a fluid to be sprayed are determined or otherwise detected. In one example, color matching system  624  (e.g., color determination system  700 ) can obtain the data and can determine/detect a color of a fluid to be sprayed (e.g., determine/detect a color of a color matching surface) as indicated by block  812 . In another example, color matching system  624  (e.g., fluid mixture system  702 ) can obtain data and can determine/detect mixture requirements for a fluid to be sprayed (e.g., determine a ratio, flow rate, volume of fluids to, for instance, generate [e.g., mix] a fluid having a determined color) as indicated by block  814 . In another example, color matching system  624  can obtain the data and can determine/detect a number of other characteristics relative to a fluid to be sprayed as indicated by block  816 . 
     Upon determining/detecting characteristics relative to a fluid to be sprayed, processing proceeds to block  818  where control/action signal generator  710  generates an action signal. In one example, action signals can be used to control characteristics, parameters, etc., of architecture  600  (e.g., spraying system  100 , computing device  200 , mixing machine  300 ), including subsystems thereof as indicated by block  820 , to generate user interface display(s) (or other indication(s)/recommendation(s), such as an alert) as indicated by block  822 , or in other ways as indicated by block  824 . 
     Control signals can be used, for example, to control fluid pathway  175  (e.g., activate, adjust, etc., metering elements  176 ), sensor(s)  602  (e.g., adjust lighting, viewing angle, etc.), fluid conveyance  608  (e.g., activate, adjust, etc. motor(s)  636 , pump(s)  638 , pressure vessel(s)  640 , etc.). In one example, based on a color and/or mixture requirement determined by color matching system  624 , a control signal can be generated to control the flow of fluids from fluid sources such that a fluid with a desired color is generated for spraying. A variety of other control signals can be generated to control components of architecture  600  in a variety of ways. 
     A user interface display can be generated on, for example, display  114 , display  202  and/or display  302 , as well as other interfaces, and can indicate a variety of information, for instance, but not limited to information relative to a mixture of fluid, characteristics relative to a color of fluid, current operating information (e.g. battery life, distance from a surface, orientation of spraying system  100 , amount of fluid left, etc.), recommendations, indications, alerts, as well as numerous other information. However, other user interface displays can be generated as well. 
     Processing then turns to block  826  where it is determined whether additional data has been received by color matching system  624 . If, at block  826 , it is determined that additional data has been received, processing proceeds at block  810  where characteristics relative to a fluid to be sprayed are determined. If, however, it is determined that additional data has not been obtained, processing turns to block  828 , where it is determined if operation of architecture  600  has finished. If, at block  828 , it is determined that the operation has not finished, then processing proceeds at block  826  where it is determined if additional data has been obtained. If, however, it is determined that the operation has finished, then operation  800  ends. 
     The operation shown in  FIG. 18  is one example of the operation of the system shown in  FIG. 16  in determining a variety of quality characteristics and/or metrics relative to architecture  600  (e.g., spraying system  100 , computing device  200  and/or mixing machine  300 ). It is to be understood that the operation can be carried out at any time or at any point throughout a spraying operation, or even if a spraying operation is not currently underway. Further, while the operation will be described in accordance with architecture  600 , it is to be understood that other architectures, systems, devices, machines, etc. with a color matching system  624  can be used as well. 
     Operation  900  begins at block  902  where data is obtained (e.g., received, accessed, etc.) by color matching system  624 . Data (e.g., sensor data and/or values indicative of sensed variables, etc.) can be obtained from sensor(s)  602  as indicated by block  904 . However, data can also be obtained from a variety of other sensors of other systems. Sensor data can include, for example, sensor data indicative of a color of a fluid sprayed (e.g., on a surface). For instance, a captured image of a sprayed surface by a color sensor, for example, a camera or other imaging/optical sensor. In another example, sensor data can include, for example, sensor data indicative of an operating characteristic/parameter of architecture  600  (e.g., flow rate of fluid in fluid pathway  175 , remaining fluid in fluid compartments  154  or fluid containers  159 , remaining fluid in pressure vessel(s), etc.). 
     Data can be obtained from data store  606  as indicated by block  906 . However, data can also be obtained from a variety of other data stores of other systems. Data from a data store can include, for example, determined and/or preprogrammed fluid colors, determined and/or preprogrammed fluid mixture requirements, saved user inputs, as well as a variety of other data in a data store relative to quality characteristics and/or metrics of a fluid to be sprayed. Data can also be obtained from a variety of other sources as indicated by block  808 . Other data can include, but is not limited to, user inputs. 
     Upon obtaining data, processing turns to block  910  where characteristics and/or metrics relative to architecture  600 , including, but not limited to, quality characteristics and/or metrics relative to a fluid to be sprayed (or already sprayed). In one example, color matching system  624  (e.g., quality determination system  705 ) can obtain the data and can determine and/or detect quality characteristics and/or metrics relative to a color of fluid to be sprayed or already sprayed (e.g., determine/detect color of fluid sprayed on surface and, for instance, compare to the determined, preprogrammed, user selected color, etc.) as indicated by block  912 . In another example, color matching system  624  (e.g., quality determination system  705 ) can obtain data and can determine/detect quality characteristics and/or metrics relative to a mixture of fluid (e.g., determine/detect the mixture [e.g., ratio, flow rate, volume of fluids, etc.] of the fluid sprayed and, for instance, compare to the determined, preprogrammed, user selected mixture requirements, etc.) as indicated by block  914 . In another example, color matching system  624  can obtain the data and can determine/detect a number of other quality characteristics and/or metrics relative to a fluid to be sprayed (or already sprayed) as indicated by block  916 . 
     Upon determining/detecting quality characteristics and/or metrics relative to a fluid to be sprayed (or already sprayed), processing proceeds to block  918  where control/action signal generator  710  generates an action signal. In one example, action signals can be used to control characteristics, parameters, etc. of architecture  600  (e.g., spraying system  100 , computing device  200 , mixing machine  300 ) including subsystems thereof as indicated by block  920 , to generate user interface display(s) (or other indication(s)/recommendation(s), such as an alert) as indicated by block  922 , or in other ways as indicated by block  924 . 
     Control signals can be used, for example, to control fluid pathway  175  (e.g., activate, adjust, etc., metering elements  176 ), sensor(s)  602  (e.g., adjust lighting, viewing angle, etc.), fluid conveyance system  608  (e.g., activate, adjust, etc. motor(s)  636 , pump(s)  638 , pressure vessel(s)  640 , etc.). In one example, based on determined/detected quality characteristics and/or metrics of a color and/or mixture of a fluid to be sprayed (or already sprayed), a control signal can be generated to control the flow of fluids from fluid sources. In some examples, the control signal is further based on a comparison to determined, preprogrammed, and/or user selected color and/or mixture requirements, etc. 
     A user interface display can be generated on, for example, display  114 , display  202  and/or display  302 , as well as other interfaces, and can indicate a variety of information, for instance, but not limited to, information relative to quality characteristics and/or metrics of a fluid to be sprayed (or already sprayed), current operating information (e.g., battery life, distance from surface, orientation of spraying system  100 , amount of fluid left, etc.), recommendations (e.g., recommended mixture to compensate/correct quality), indications, alerts, as well as numerous other information. However, other user interface displays can be generated as well. 
     A variety of other actions signals can be generated at block  918 , as indicated by block  924 , including, but not limited to, action signals to store and/or update already stored information relative to a color and/or mixture of fluids in, for example, a data store (e.g.,  606 ). For example, upon determining/detecting quality characteristics and/or metrics relative to a fluid to be sprayed (or already sprayed) color matching system  624  (e.g., quality determination system  705 ) can update (e.g., calibrate) information relative to determined, preprogrammed, user selected information relative to, for example, color and/or mixture requirements of a fluid to be sprayed. In this way, colors and/or mixtures of fluids can be dynamically updated and can be calibrated for a variety of different working environments, characteristics, etc. 
     Processing then turns to block  926  where it is determined whether additional data has been received by color matching system  624 . If, at block  926 , it is determined that additional data has been received, processing proceeds at block  910  where quality characteristics and/or metrics relative to a fluid to be sprayed (or already sprayed) are determined. If, however, it is determined that additional data has not been obtained, processing turns to block  928 , where it is determined if operation of architecture  600  has finished. If, at block  928 , it is determined that the operation has not finished, then processing proceeds at block  926  where it is determined if additional data has been obtained. If, however, it is determined that the operation has finished, then operation  900  ends. 
     It will be noted that the above discussion has described a variety of different systems, components and/or logic. It will be appreciated that such systems, components and/or logic can be comprised of hardware items (such as processors and associated memory, or other processing components, some of which are herein) that perform the functions associated with those systems, components and/or logic. In addition, the systems, components and/or logic can be comprised of software that is loaded into a memory and is subsequently executed by a processor or server, or other computing component, as described below. The systems, components and/or logic can also be comprised of different combinations of hardware, software, firmware, etc., some examples of which are described below. These are only some examples of different structures that can be used to form the systems, components and/or logic described above. Other structures can be used as well. 
     The present discussion has mentioned processors and servers. In one example, the processors and servers include computer processors with associated memory and timing circuitry, not separately shown. They are functional parts of the systems or devices to which they belong and are activated by and facilitate the functionality of the other components or items in those systems. 
     Also, a number of user interface displays have been discussed. They can take a wide variety of different forms and can have a wide variety of different user actuatable input mechanisms disposed thereon. For instance, the user actuatable input mechanisms can be text boxes, check boxes, icons, links, drop-down menus, search boxes, etc. They can also be actuated in a wide variety of different ways. For instance, they can be actuated using a point and click device (such as a track ball or mouse). They can be actuated using hardware buttons, switches, a joystick or keyboard, thumb switches or thumb pads, etc. They can also be actuated using a virtual keyboard or other virtual actuators. In addition, where the screen on which they are displayed is a touch sensitive screen, they can be actuated using touch gestures. Also, where the device that displays them has speech recognition components, they can be actuated using speech commands. 
     Also, the figures show a number of blocks with functionality ascribed to each block. It will be noted that fewer blocks can be used so the functionality is performed by fewer components. Also, more blocks can be used with the functionality distributed among more components. 
       FIG. 19  is a block diagram of one example of architecture  600 , shown in  FIG. 15 , where spraying system  100 , computing device  200 , and mixing machine  300  communicate with elements in a remote server architecture  1002 . In an example, remote server architecture  1002  can provide computation, software, data access, and storage services that do not require end-user knowledge of the physical location or configuration of the system that delivers the services. In various examples, remote servers can deliver the services over a wide area network, such as the internet, using appropriate protocols. For instance, remote servers can deliver applications over a wide area network and they can be accessed through a web browser or any other computing component. Software or components shown in  FIG. 15  as well as the corresponding data, can be stored on servers at a remote location. The computing resources in a remote server environment can be consolidated at a remote data center location or they can be dispersed. Remote server infrastructures can deliver services through shared data centers, even though they appear as a single point of access for the user. Thus, the components and functions described herein can be provided from a remote server at a remote location using a remote server architecture. Alternatively, they can be provided from a conventional server, or they can be installed on client devices directly, or in other ways. 
     In the example shown in  FIG. 19  some items are similar to those shown in  FIG. 15  and they are similarly numbered.  FIG. 19  specifically shows that control system  604  (including color matching  624 ) and/or data store  606  can be located at a remote server location  1004 , illustratively shown in  FIG. 19  as a cloud server, though other remote server locations are also contemplated herein. Therefore, spraying system  100 , computing device  200 , and/or mixing machine  300  access those systems through remote server location  1004 . 
       FIG. 19  also depicts another example of a remote server architecture.  FIG. 19  shows that it is also contemplated that some elements of  FIG. 15  are disposed at remote server location  1004  while others are not. By way of example, data store  606  can be disposed at a location separate from location  1004  and accessed through the remote server at location  1004 . Alternatively, or in addition, control system  604  can be disposed at location(s) separate from location  1004  and accessed through the remote server at location  1004 . 
     Regardless of where they are located, they can be accessed directly by spraying system  100 , computing device  200  and/or mixing machine  300 , through a network (either a wide area network or a local area network), they can be hosted at a remote site by a service, or they can be provided as a service, or accessed by a connection service that resides in a remote location. Also, the data can be stored in substantially any location and intermittently accessed by, or forwarded to, interested parties. For instance, physical carriers can be used instead of, or in addition to, electromagnetic wave carriers. In such an example, where cell coverage is poor or nonexistent, another system, device and/or machine can have an automated information collection system. The collected information can then be forwarded to the main network as the other system, device and/or machine reaches a location where there is cellular coverage (or other wireless coverage). All of these architectures are contemplated herein. Further, the information can be stored on the spraying system, computing device and/or mixing machine until the spraying system, computing device, and/or mixing machine enters a covered location. The spraying system, computing device, mixing machine, themselves, can then send and receive the information to/from the main network. 
       FIG. 20  is one example of a computing environment in which elements of  FIG. 15 , or parts of it, (for example) can be deployed. With reference to  FIG. 20 , an example system for implementing some embodiments includes a computing device in the form of a computer  1210 . Components of computer  1210  may include, but are not limited to, a processing unit  1220  (which can comprise processors or servers from previous FIGS.), a system memory  1230 , and a system bus  1221  that couples various system components including the system memory to the processing unit  1220 . The system bus  1221  may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. Memory and programs described with respect to  FIG. 15  can be deployed in corresponding portions of  FIG. 20 . 
     Computer  1210  typically includes a variety of computer readable media. Computer readable media can be any available media that can be accessed by computer  1210  and includes both volatile and nonvolatile media, removable and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media is different from, and does not include a modulated data signal or carrier wave. It includes hardware storage media including both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by computer  1210 . Communication media may embody computer readable instructions, data structures, program modules or other data in a transport mechanism and includes any information delivery media. The term “modulated data signal” means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. 
     The system memory  1230  includes computer storage media in the form of volatile and/or nonvolatile memory such as read only memory (ROM)  1231  and random access memory (RAM)  1232 . A basic input/output system  1233  (BIOS), containing the basic routines that help to transfer information between elements within computer  1210 , such as during start-up, is typically stored in ROM  1231 . RAM  1232  typically contains data and/or program modules that are immediately accessible to and/or presently being operated on by processing unit  1220 . By way of example, and not limitation,  FIG. 20  illustrates operating system  1234 , application programs  1235 , other program modules  1236 , and program data  1237 . 
     The computer  1210  may also include other removable/non-removable volatile/nonvolatile computer storage media. By way of example only,  FIG. 20  illustrates a hard disk drive  1241  that reads from or writes to non-removable, nonvolatile magnetic media, an optical disk drive  1255 , and nonvolatile optical disk  1256 . The hard disk drive  1241  is typically connected to the system bus  1221  through a non-removable memory interface such as interface  1240 , and optical disk drive  1255  is typically connected to the system bus  1221  by a removable memory interface, such as interface  1250 . 
     Alternatively, or in addition, the functionality described herein can be performed, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), Application-specific Integrated Circuits (e.g., ASICs), Application-specific Standard Products (e.g., ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), etc. 
     The drives and their associated computer storage media discussed above and illustrated in  FIG. 20 , provide storage of computer readable instructions, data structures, program modules and other data for the computer  1210 . In  FIG. 20 , for example, hard disk drive  1241  is illustrated as storing operating system  1244 , application programs  1245 , other program modules  1246 , and program data  1247 . Note that these components can either be the same as or different from operating system  1234 , application programs  1235 , other program modules  1236 , and program data  1237 . 
     A user may enter commands and information into the computer  1210  through input devices such as a keyboard  1262 , a microphone  1263 , and a pointing device  1261 , such as a mouse, trackball or touch pad. Other input devices (not shown) may include a joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit  1220  through a user input interface  1260  that is coupled to the system bus, but may be connected by other interface and bus structures. A visual display  1291  or other type of display device is also connected to the system bus  1221  via an interface, such as a video interface  1290 . In addition to the monitor, computers may also include other peripheral output devices such as speakers  1297  and printer  1296 , which may be connected through an output peripheral interface  1295 . 
     The computer  1210  is operated in a networked environment using logical connections (such as a local area network—LAN, or wide area network—WAN or a controller area network—CAN) to one or more remote computers, such as a remote computer  1280 . 
     When use in a LAN networking environment, the computer  1210  is connected to the LAN  1271  through a network interface or adapter  1270 . When used in a WAN networking environment, the computer  1210  typically includes a modem  1272  or other means for establishing communications over the WAN  1273 , such as the Internet. In a networked environment, program modules may be stored in a remote memory storage device.  FIG. 20  illustrates, for example, that remote application programs  1285  can reside on remote computer  1280 . 
     At least some examples are described herein in the context of applying a coating material, such as paint, to a surface. As used herein, “paint” includes substances composed of coloring matter or pigment suspending in a liquid medium as well as substances that are free of coloring matter or pigment. “Paint” can also include preparatory coatings, such as primers. “Paint” can be applied to coat a surface as a liquid or a gaseous suspension, for example, and the coating provided can be opaque, transparent, or semi-transparent. Some particular examples include, but are not limited to, latex paint, oil-based paint, stain, lacquers, varnish, inks, and the like. 
     It should also be noted that the different examples described herein can be combined in different ways. That is, parts of one or more examples can be combined with parts of one or more other examples. All of this is contemplated herein. 
     Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.