Abstract:
Systems and methods are provided for estimating a quality of air in proximity to a vehicle. In one embodiment, a method includes: determining a radius of the vehicle; estimating a number of vehicles within the radius of the vehicle; estimating the quality of air based on the number of vehicles; and selectively generating a control signal to an air inlet valve based on the quality of air.

Description:
FIELD 
       [0001]    The present disclosure generally relates to the field of vehicles and, more specifically, to methods and systems for estimating a quality of air based on vehicle traffic conditions. 
       BACKGROUND 
       [0002]    Certain vehicles today may rely on sensor data received from one or more air quality sensors to determine air quality. The air quality sensors sense the quality of the ambient air in proximity to the vehicle and provide the vehicle with the sensed data. The vehicle interprets the sensed data to determine a quality of the air. The inclusion of such sensors in a vehicle may increase costs. 
         [0003]    Accordingly, it is desirable to provide methods and systems for estimating air quality without the use of an air quality sensor. Furthermore, it is desirable to provide methods and systems for compensating when the determined air quality is poor. Furthermore, other desirable features and characteristics of the present invention will be apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background. 
       SUMMARY 
       [0004]    Systems and methods are provided for estimating a quality of air in proximity to a vehicle. A method includes: determining a radius of the vehicle; estimating a number of vehicles within the radius of the vehicle; estimating the quality of air based on the number of vehicles; and selectively generating a control signal to an air inlet valve based on the quality of air. 
         [0005]    A system includes a first module that estimates, by a processor, a number of vehicles within a radius of the vehicle. The system further includes a second module that estimates, by a processor, the quality of air based on the number of vehicles. The system further includes a third module that selectively generates, by a processor, a control signal to an air inlet valve based on the quality of air. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The present disclosure will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and 
           [0007]      FIG. 1  is a functional block diagram illustrating a vehicle having an air quality estimation and control system in accordance with various embodiments; 
           [0008]      FIG. 2  is a dataflow diagram illustrating an air quality estimation and control module in accordance with various embodiments; and 
           [0009]      FIG. 3  is a flowchart illustrating an air quality estimation and control method in accordance with various embodiments. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0010]    The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description. As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic, and/or processor device, individually or in any combination, including without limitation: application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality. 
         [0011]    With reference to  FIG. 1 , a vehicle  100  is shown that includes an air quality estimation and control system  102  in accordance with various embodiments. Although the figures shown herein depict an example with certain arrangements of elements, additional intervening elements, devices, features, or components may be present in an actual embodiment. It should also be understood that  FIG. 1  is merely illustrative and may not be drawn to scale. 
         [0012]    As depicted in  FIG. 1 , the vehicle  100  generally includes a chassis  104 , a body  106 , front wheels  108 , rear wheels  110 , a steering system  112 , a heating ventilation and/or air conditioning (HVAC) system  114 , and a propulsion system  116 . In various embodiments, the body  106  is arranged on the chassis  104  and substantially encloses the other components of the vehicle  100 . The body  106  and the chassis  104  may jointly form a frame. The wheels  108 - 110  are each rotationally coupled to the chassis  104  near a respective corner of the body  106 . The steering system  112 , at a minimum, includes a steering wheel  118  coupled to a steering shaft  120 . In various embodiments, the steering system  112  further includes various other features (not depicted in  FIG. 1 ), such as a steering gear, intermediate connecting shafts between the column and the gear, connection joints, either flexible or rigid, allowing desired articulation angles between the intermediate connecting shafts, and tie-rods. The steering gear, in turn, comprises a rack, input shaft, and internal gearing. The steering system  112  influences the steerable front road wheels  108  during steering based upon any torque received from a driver of the vehicle  100  via the steering wheel  118 . 
         [0013]    The HVAC system  114  includes one or more components to control the in-vehicle air temperature and air quality. In various embodiments, the HVAC system  114  includes, amongst other features, an air inlet flap  122  that permits ambient air to flow from outside the vehicle  100  to inside of the vehicle  100 . The air inlet flap  122  may be mechanically and/or electronically controlled by one or more actuator devices (not shown). 
         [0014]    The propulsion system  116  may include any one of, or combination of, a number of different types of propulsion systems, such as, for example, a gasoline or diesel fueled combustion engine, a “flex fuel vehicle” (FFV) engine (i.e., using a mixture of gasoline and ethanol), a gaseous compound (e.g., hydrogen or natural gas) fueled engine, a combustion/electric motor hybrid engine, and an electric motor. As can be appreciated, the vehicle  100  may be any one of a number of different types of automobiles, such as, for example, but not limited to, a sedan, a wagon, a truck, or a sport utility vehicle (SUV), and may be two-wheel drive (2WD) (i.e., rear-wheel drive or front-wheel drive), four-wheel drive (4WD) or all-wheel drive (AWD), or any other type of vehicle. 
         [0015]    The vehicle  100  further includes at least one controller  124  that is communicatively coupled to one or more sensors  126 - 130  and a global positioning system (GPS)  132 . In various embodiments, the sensors  126 - 130  include, but are not limited to, an ambient air temperature sensor  126 , a wind speed sensor  128 , and a vehicle speed sensor  130 . The ambient air temperature sensor  126  senses a temperature of the ambient air outside of the vehicle  100  and generates temperature sensor signals based thereon. The wind speed sensor  128  senses a speed of the air or wind outside of the vehicle  100  and generates wind speed sensor signals based thereon. The vehicle speed sensor  130  senses a rotational speed of the one or more wheels  108 - 110  of the vehicle  100  and generates vehicle speed sensor signals based thereon. The GPS  132  includes one or more communication devices for communicating with one or more satellites. The GPS  132  provides time and location information to the controller  124  based on the communications with the satellites. 
         [0016]    The controller  124  receives and processes the various sensor signals and the GPS information and controls one or more components of the vehicle  100  based thereon. In various embodiments, the controller  124  controls the HVAC system  114 . As can be appreciated, the controller  124  may control other vehicle components such as, but not limited to, the steering system  112 , the propulsion system  116 , and/or other components not described. 
         [0017]    In various embodiments, the controller  124  includes an air quality estimation and control module  134 . The air quality estimation and control module  134  receives the sensor signals and the GPS information. The air quality estimation and control module  134  processes the sensor signals and the GPS information to estimate a quality of the air outside of the vehicle  100 . The air quality estimation and control module  134  generates control signals to control the HVAC system  122  based on the estimated air quality. For example, if the estimated air quality is poor, then the air quality estimation and control module  134  generates control signals to control the inlet flap  122  of the HVAC system  114  such that intrusion of the pollutants into the vehicle  100  is prevented. For example, the control signals control one or more actuator devices associated with the inlet flap  122  to control a position of the inlet flap  122 . 
         [0018]    Referring now to  FIG. 2  and with continued reference to  FIG. 1 , a dataflow diagram illustrates the air quality estimation and control module  134  of  FIG. 1  in accordance with various embodiments. As can be appreciated, various embodiments of the air quality estimation and control module  134 , according to the present disclosure, may include any number of sub-modules. For example, the sub-modules shown in  FIG. 2  may be combined and/or further partitioned to similarly estimate air quality and control one or more features of the HVAC system  122 . As discussed above, inputs to the air quality estimation and control module  134  may be received from the sensors  126 - 130  of the vehicle  100  and/or other sensors (not shown), received from other controllers (not shown) of the vehicle  100 , received from other modules of the controller  124 , or determined by other sub-modules (not shown) of the air quality estimation and control module  134 . In various embodiments, the air quality estimation and control module  134  includes a radius determination module  140 , a vehicle number determination module  142 , an air quality estimation module  144 , a recirculation control module  146 , a radius datastore  148 , and an air quality datastore  150 . 
         [0019]    The radius determination module  140  receives as input ambient air temperature data  152 . The ambient air temperature data  152  may be based on, for example, the sensor signals received from the ambient air temperature sensor  126 . The radius determination module  140  determines a radius  154  based on the ambient air temperature data  152 . The radius  154  corresponds to a radius around the vehicle  100  (e.g., where the vehicle is the center of the radius). For example, the radius  154  may be determined from a value  156  that is determined from a lookup table stored in the radius datastore  148 . 
         [0020]    The lookup table may be a one dimensional interpolation table that is indexed by ambient air temperature. The radius values can be populated in the lookup table based on relationships between ambient air temperature, air density, and smoke travel characteristics. For example, if ambient air temperature is low, the air density will be higher. A higher air density will not allow smoke to settle on the ground. Higher smoke temperature and lower pressure will cause smoke to flow upwards. In this case there is less probability that the smoke will travel a long distance to reach the vehicle  100 . Thus, at low ambient air temperatures, the radius to evaluate around the vehicle  100  may be set to a smaller value (e.g., Radius=200 m for ambient air temperature=5 degrees and less, 500 m for ambient air temperature=6 degrees to 20 degrees, etc.]); and at higher ambient air temperatures, the radius to evaluate around the vehicle may be set to a greater value (e.g., 1 Km for ambient air temperature=21 degrees or more). 
         [0021]    The vehicle number determination module  142  receives as input the determined radius  154  and GPS data  158 . The GPS data  158  may include coordinates of other vehicles within a proximity of the vehicle  100 . The GPS data  158  may be based on, for example, the information received from the GPS  132 . The vehicle number determination module  142  determines a number of vehicles  160  within the determined radius  154  of the vehicle  100  based on the GPS data  158 . For example, the vehicle number determination module  142  keeps a count of the number of other vehicles having coordinates within the determined radius of the vehicle  100  as identified in the GPS data  158 ; and the count is set equal to the number of vehicles  160 . 
         [0022]    The air quality estimation module  144  receives as input the number of vehicles  160 , wind speed data  162 , and vehicle speed data  164 . The wind speed data  162  may be based on, for example, the sensor signals received from the wind speed sensor  128 . The vehicle speed data  164  may be based on, for example, the sensor signals received from the vehicle speed sensor  130 . The air quality estimation module  144  estimates a quality of air  166  in proximity to the vehicle  100  based on the received data  160 - 164 . For example, the estimated air quality  166  may be determined from a value  168  that is determined from a lookup table stored in the air quality datastore  150 . 
         [0023]    The lookup table may be a one dimensional interpolation table that is indexed by the number of vehicles  160 . For example, the air quality values  168  can be populated in the lookup table based on a predetermined emission value per vehicle. In another example, the air quality values  168  can indicate low, medium, or high and can be based on a range of vehicles (e.g., number of vehicles  160 &lt;5, then the quality of air  166  is set to no pollution; number of vehicles  160 =5-15, then the quality of air  166  is set to low pollution; number of vehicles  160 &gt;15, then the quality of air  166  is set to high pollution). As can be appreciated, in various embodiments, information about the other vehicles (e.g., make, model, year, etc.) may also be used to determine the air quality values  168  if it is available from the GPS  132  or other system. 
         [0024]    The recirculation control module  146  receives as input the estimated air quality  166 . The recirculation control module  1446  evaluates the estimated air quality  166  and selectively generates controls signals  170  to control the HVAC system  114  based on the evaluation. For example, the recirculation control module  146  generates control signals  170  to control the inlet flap  122  to a position that prevents airflow into the vehicle  100  when the air quality estimation is greater than a first threshold. In another example, the recirculation control module  146  generates control signals  170  to control the inlet flap  122  to a second position to permit airflow into the vehicle  100  when the air quality estimation is less than a second threshold. As can be appreciated, the first threshold and the second threshold may be the same or different values. 
         [0025]    With reference now to  FIG. 3 , a flowchart of a method  200  for estimating a quality of air in proximity to the vehicle and controlling the HVAC system based thereon is shown in accordance with exemplary embodiments. The method  200  can be utilized in connection with the vehicle  100  and the air quality estimation and control system  102 , in accordance with exemplary embodiments. As can be appreciated in light of the disclosure, the order of operation within the method is not limited to the sequential execution as illustrated in  FIG. 3 , but may be performed in one or more varying orders as applicable and in accordance with the present disclosure. 
         [0026]    As depicted in  FIG. 3 , the method may begin at  205 . The ambient air temperature sensor signals are received and processed to determine the ambient air temperature data  152  at  210 . The wind speed sensor signals are received and processed to determine the wind speed sensor data  162  at  220 . The vehicle speed sensor signals are processed to determine the vehicle speed data  164  at  230 . The wind speed sensor data  162  and the vehicle speed sensor data  164  is evaluated at  240  and  250 . For example, it is determined whether the wind speed is greater than a wind speed pollution threshold at  240 , and whether the vehicle speed is greater than a vehicle speed pollution threshold at  250 . If the wind speed is greater than the wind speed threshold at  240 , or the vehicle speed is less than the vehicle speed pollution threshold at  250 , it is determined that there is no effective air pollution at  260  and the method may end at  270 . 
         [0027]    If, however, the wind speed is less than the wind speed pollution threshold at  240  and the vehicle speed is less than the vehicle speed pollution threshold at  250 , the method continues with estimating the quality of air  166  outside of the vehicle  100  and optionally, controlling the HVAC system  114  of the vehicle  100  based thereon at  280 - 300 . For example, the radius  154  is determined based on the ambient air temperature data  152  at  280 . The number of vehicles  160  within the determined radius  154  is determined based on the GPS data  158  at  290 . The air quality  166  is estimated based on the number of vehicles  160  at  300 . 
         [0028]    Optionally, the estimated air quality is evaluated at  310 . For example, if the estimated air quality  166  is greater than a threshold at  310 , the control signals  170  are generated to control the inlet flap  122  to prevent air from entering the vehicle at  320 . Otherwise, the method may end at  270 . 
         [0029]    While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.