Grid shutter control for brake cooling

Abstract

The present disclosure provides "grille shutter control for brake cooling". A vehicle control system for a vehicle may include a brake assembly to apply a negative torque to one or more wheels of the vehicle; a grille shutter assembly that, when opened, directs airflow above the brake assembly and, when closed, prevents airflow from facing the brake assembly; and a controller that calculates a target brake temperature, the controller operably coupled to the grille shutter assembly to control positioning of the grille shutter assembly based on a comparison of a current brake temperature and the target brake temperature.

Description

Technical Field

[0001] Exemplary embodiments relate generally to vehicle aerodynamics and, more particularly, to a controllable aerodynamic grille for cooling brakes based on situational awareness. Background Art

[0002] Vehicles, and particularly electric vehicles, can generally benefit from good aerodynamics. For example, an electric vehicle can increase range for a given battery capacity if aerodynamics are enhanced, or the same range can be achieved with a smaller battery. At the same time, again as vehicles become further electrified, electrical components that aid in the application of brake torque are becoming more common. While air can be used in conjunction with cooling brake components, such cooling may degrade aerodynamics. Therefore, it may be desirable to strike an optimal balance between aerodynamic performance and temperature control of brake components. Summary of the invention

[0003] According to an exemplary embodiment, a vehicle control system for a vehicle may be provided. The system may include: a brake assembly for applying negative torque to one or more wheels of the vehicle; a grille shutter assembly that directs airflow over the brake assembly when open and prevents airflow toward the brake assembly when closed; and a controller that calculates a target brake temperature, the controller being operably coupled to the grille shutter assembly to control positioning of the grille shutter assembly based on a comparison of a current brake temperature with the target brake temperature.

[0004] In another exemplary embodiment, a method of providing selective air cooling to a brake assembly of a vehicle may be provided. The method may include: receiving status information from a sensor network of the vehicle; determining a target temperature of a brake component of the brake assembly based on the status information; comparing a current brake temperature to the target temperature; and controlling airflow for cooling the brake component via a positioning aerodynamic device based on the comparison of the current brake temperature and the target temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Having thus generally described the invention, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and in which:

[0006] Figure 1 A block diagram of a vehicle control system according to an exemplary embodiment is shown;

[0007] Figure 2 According to an exemplary embodiment, Figure 1 A block diagram of some components of a vehicle control system of a vehicle control system;

[0008] Figure 3 shows a perspective view of a vehicle having a grille shutter assembly according to an exemplary embodiment;

[0009] Figure 4 A block diagram showing a control algorithm for controlling a grille shutter assembly provided on a vehicle according to an exemplary embodiment; and

[0010] Figure 5 A block diagram of a method for providing a balance between brake cooling and vehicle aerodynamics is shown according to an exemplary embodiment. DETAILED DESCRIPTION

[0011] Some exemplary embodiments will now be described more fully below with reference to the accompanying drawings, in which some but not all exemplary embodiments are shown. In fact, the examples described and depicted herein should not be construed as limiting the scope, applicability or configuration of the present disclosure. Rather, these exemplary embodiments are provided so that the present disclosure will meet applicable requirements. The same reference numerals always refer to the same elements. In addition, as used herein, the term "or" will be interpreted as a logical operator whose result is true whenever one or more of its operands are true. As used herein, an operable connection should be understood to involve a direct or indirect connection, in which case the connection can achieve functional interconnection of components that are operably connected to each other.

[0012] Some exemplary embodiments described herein may provide an enhanced system for automatic aerodynamic control that balances the provision of brake component cooling with aerodynamic performance. Exemplary embodiments effectively aim to keep brake components as cool as possible based on aerodynamic considerations. In some cases, the control system provided herein may utilize information about vehicle payload, vehicle route selection, or other factors about the environment that may be known in advance or in real time, and such information may be used to define a target temperature below which the brake components may be kept in an effort to be kept. When the brakes are kept cool, aerodynamic performance may be maximized by closing the grille shutters to suppress cooling airflow. However, as the brakes heat up, the grille shutters may be opened proportionally until such temperatures reach a level at which fully open shutters can be supplied while reducing aerodynamic performance. In addition, in challenging situations where higher temperatures are encountered, it may also be possible to bias the application of brake torque toward reducing the use of friction brakes. For future electric vehicles (EVs), optimizing the balance between component cooling and aerodynamic performance may allow for increased range for a given battery capacity. However, in addition to EVs, the benefits of optimizing this balance may also be extended to internal combustion engine (ICE) vehicles. As a result, vehicle performance and driver satisfaction may also be improved.

[0013] Figure 1A block diagram of a vehicle control system 100 of an exemplary embodiment is shown. Components of the vehicle control system 100 may be incorporated into a vehicle 110 (e.g., via an operative connection to a chassis of the vehicle 110 and / or an electronic control system of the vehicle 110). It is worth noting that although Figure 1 The components of the vehicle control system 100 may be connected to the chassis of the vehicle 110, but it should be understood that such connection may be direct or indirect. In addition, some components of the vehicle control system 100 may be connected to the vehicle 110 via intermediate connections to other components of the chassis or other systems or components.

[0014] The vehicle control system 100 may include a grille shutter assembly 120 that may include one or more aerodynamic devices (e.g., shutters, spoilers, vents, air guides, etc.) that may be moved in response to control initiated by the vehicle control system 100 while the vehicle 110 is in motion. In its simplest form, the grille shutter assembly 120 may include a single aerodynamic device (e.g., shutter) that may be disposed in a passage 122 having a grille formed in a portion of the body of the vehicle 110. The device (e.g., shutter) may be repositioned within the passage 122 to change the amount of airflow 124 that is able to enter the grille and pass through the passage 122. Thus, for example, the shutter may be repositioned to change the device between an open state (in which airflow through the passage is maximized) and a closed state (in which airflow 124 is not allowed to pass through the passage). Changes between the open and closed states, and changes in the shutter position therebetween, may be considered state changes of the grille shutter assembly 120. Thus, for example, the open state may be 100% open, the closed state may be 0% open, and various (or even continuous) positions between the open state and the closed state may be included to define respective percentages of opening that the shutter may be in each respective position. The vehicle control system 100 may include programming and a programmatically controlled physical structure that enables initiation of changes in the state of the grille shutter assembly 120 based on various conditions or information related to vehicle status, vehicle location, route selection, load, and based on driver or operator control or preference.

[0015] The grille shutter assembly 120 of the exemplary embodiment may be dynamic and intelligently controlled. The "intelligently controlled" nature of the grille shutter assembly 120 refers to the fact that automatic adjustments are made to optimize the positioning of the aerodynamic devices (e.g., shutters). The "dynamic" nature of the grille shutter assembly 120 refers to the fact that it can be dynamically repositioned in response to real-time conditions and status information to actively change the aerodynamic performance of the vehicle 110 while also actively changing the amount of air cooling provided to the brake assembly 126 of the vehicle 110. Thus, for example, when an operator has enabled automatic control of the grille shutter assembly 120 by selecting a mode in which the vehicle control system 100 is operable, the state of the dynamic device may be controlled based on the status information, the current position, and various other conditions experienced by the vehicle 110. Thus, for example, various changes in conditions or vehicle states may dynamically cause a change in the state of the aerodynamic device based on the programmed rules or algorithms used to control the grille shutter assembly 120.

[0016] In an exemplary embodiment, the vehicle control system 100 may include a repositioning assembly (e.g., actuator 130) that may be provided as part of the vehicle control system 100 to reposition or move the grille shutter assembly 120 under the control of a controller 140 (or control module) of the vehicle control system 100. In some cases, the controller 140 may be part of a vehicle dynamics module (VDM) or other control system of the vehicle 110 that is configured to perform other tasks related or unrelated to aerodynamic control or performance management. However, in some cases, the controller 140 may be a dedicated or stand-alone controller. Further, in some cases, the controller 140 may be a proportional-integral-derivative (PID) controller.

[0017] The operator (or driver) can disable or enable the operation of the actuator 130 by using the user interface 132. For example, in one or more modes, the actuator 130 can be disabled, and in one or more other modes, the actuator 130 can be enabled to move under the control of the controller 140. As an alternative to having the mode directly disable or enable the actuator 130, the actuator 130 can be indirectly controlled via the controller 140. Thus, in some cases, the user interface 132 can interact with the controller 140 instead of the actuator 130. The user interface 132 can be internal or external relative to the vehicle 110. Thus, for example, when internal, the user interface 132 can include a switch, a joystick, a button, a mouse, a touch screen display, or any other suitable human-machine interface (HMI). Also as an example, when external, the user interface 132 can be an external console, a smart phone, or other interface component that can communicate wirelessly with the vehicle 110.

[0018] The actuator 130 may include a motion source (e.g., an electric motor, a hydraulic actuator, a pneumatic actuator, etc.) that is operably coupled to an aerodynamic device (e.g., a shutter) of the grille shutter assembly 120, either directly or via a linkage mechanism that is in turn operably coupled to the aerodynamic device of the grille shutter assembly 120. Thus, for example, the linkage mechanism may include a mechanical structure (e.g., a hinge, a link, an arm, a rod, a deformable material, etc.) that operably couples motion from the output of the motion source to the aerodynamic device. In the case where the aerodynamic device is a single shutter, one such shutter may be associated with a corresponding instance of the channel 122 leading to each of the rear wheels, and more specifically, the rear brakes at the rear wheels. However, in some cases, it may also be possible to have four channels, with one channel at each of the front and rear wheels.

[0019] In an exemplary embodiment, the controller 140 may receive information from various components or subassemblies 150 of the vehicle 110 that is used to determine the vehicle state (or environmental conditions) and the vehicle position or is associated with the various components or subassemblies. Additionally or alternatively, various sensors may be included that are operably coupled to the components or subassemblies 150 and that may provide input to the controller 140 for determining the vehicle state and position. Such sensors may be part of a sensor network 160, and the sensors of the sensor network 160 may be operably coupled to the controller 140 (and / or the components or subassemblies 150) via a vehicle communication bus (e.g., a controller area network (CAN) bus) 170.

[0020] The component or subassembly 150 may include, for example, a brake assembly 126 and / or a wheel assembly of the vehicle 110. Sensors associated with the brake assembly 126 may provide inputs such as brake pedal position, brake torque request, or brake pressure to the controller 140. Sensors associated with the wheel assembly may provide information about vehicle speed, wheel angle, etc. Other sensors of the sensor network 160 that may be operably connected to the brake assembly, wheel assembly, or other parts of the vehicle 110 may provide information related to brake torque, brake torque rate, vehicle speed change rate, individual wheel speed / angle, etc. Other examples of the component or subassembly 150 and / or corresponding sensors of the sensor network 160 may provide information related to pitch, yaw, pitch rate, yaw rate, lateral G force, throttle position, selector button position associated with chassis and / or vehicle control selection, etc. Thus, for example, the sensor may include an inclinometer, a gyroscope, an inertial measurement unit, etc. In some cases, the sensor network 160 may also include sensors for detecting weather conditions, road conditions, etc. For example, moisture sensors and temperature sensors can detect wet or icy roads, ambient temperature, brake component temperature, etc.

[0021] In some cases, cameras, microphones, rain sensors, etc. may also be used to determine road conditions. Thus, for example, the sensor network 160 may also include one or more cameras operating in the visible spectrum, infrared cameras, lidar, etc. to detect debris or other obstacles or road conditions. However, in some cases, the camera may also detect a location or position relative to a specific feature of the road ahead. For example, the camera may detect turns or straights and various tilt conditions. In addition, the camera may detect the size of the tilt, turn, or straight length. In an exemplary embodiment, the camera is also able to compare the image data with previously captured images to determine whether the location where the vehicle 110 is currently operating also happens to be the location where the vehicle 110 was operating in the past. When a location correlation occurs, a comparison between previous traversals of the location may be performed to determine the best setting (or at least the setting to be used) for the grille shutter assembly 120 at the location (currently or in the near future). However, other means may be used to determine the location instead. For example, global positioning system (GPS) data or other location sensors may also or alternatively be used.

[0022] Thus, for example, controller 140 may be capable of receiving numerous different parameters, indications, and other information that may relate to or indicate different situations or conditions associated with a vehicle state. Controller 140 may also receive information indicative of a vehicle position. Controller 140 may then be configured to use the received information defining a vehicle state and / or position associated with the execution of one or more control algorithms that may be used to provide instructions to actuator 130 in order to control the state (or position) of one or more aerodynamic devices of grille shutter assembly 120.

[0023] Figure 2 A block diagram of various components of the vehicle control system 100 of an exemplary embodiment is shown in greater detail. In this regard, for example, the controller 140 may receive state information 200 via the vehicle communication bus 170 (e.g., from the sensor network 160). The state information 200 may include any or all of the types of information described above, among others. The controller 140 may also or alternatively receive location information, or more specifically route information 202, from, for example, either or both of a camera (which may obtain image data indicating various environmental or topographical aspects of the operating environment of the vehicle 110) and a GPS device 204.

[0024] In some cases, the state information 200 may include information about a brake torque request 206 indicating the amount of negative torque requested to be applied to the wheels of the vehicle 110 using the brake assembly 126. The brake assembly 126 may include friction brakes and, in some cases, electromechanical brakes (or other electrically operated brake components). In some examples, the braking force distribution may be allocated between an electrical braking option and a mechanical braking option, as will be discussed in more detail below. The state information 200 may also include information about the payload or load of the vehicle 110. Thus, for example, the ride height sensor 208 may provide ride height information as part of the state information 200, where the ride height information indicates how much load the vehicle 110 is currently carrying. Other sensors of the sensor network 160 may also provide other information (e.g., ambient temperature, combined vehicle mass, etc.).

[0025] The processing circuitry at the controller 140 (e.g., the processor 210 and the memory 212) can process the state information 200 and the position information, or more specifically, the route information 202 by running one or more control algorithms. The control algorithm may include instructions that can be stored by the memory 212 for retrieval and execution by the processor 210. In some cases, the memory 212 may also store one or more tables (e.g., lookup tables), models, etc. and may use the information in the tables or models, the state information 200, and / or the route information 202 to perform various calculations and / or applications.

[0026] The processor 210 may be configured to execute the control algorithm 220 or multiple instances of the control algorithm 220 in series or in parallel for respective different wheels. Thus, for example, each individual instance of a wheel (and corresponding brake components associated therewith) may have its own control determination made by one instance of the control algorithm 220. Alternatively, one control determination made by the control algorithm 220 may be applied to all instances of wheels and brakes. Figure 2 , grille shutter assembly 120 is shown to include four different shutter elements 230 (eg, shutter element #1, shutter element #2, shutter element #3, and shutter element #4). This arrangement assumes that there are Figure 1120 and 121. The processor 210 may include four separate instances of channel 122, one associated with each of the four wheels of the vehicle 110. Thus, the brake assembly 126 will also include four separate local brake assemblies at each wheel (where such local brake assemblies include friction and / or electrically operable brake components). However, some embodiments may only apply shutters for the rear wheels (and corresponding rear brakes). The processor 210 may have sufficient speed and processing power to ensure that both the state information 200 and the route information 202 received via the vehicle communication bus 170 are received and processed in real time (or near real time), resulting in corresponding changes to the positioning of the grille shutter assembly 120 (and its specific shutter elements).

[0027] As described above, the controller 140 may execute one or more control algorithms at a time to control the grille shutter assembly 120 in a situationally aware manner. The controller 140 may perform calculations or determinations associated with the control algorithms to ultimately position the shutter elements 230 of the grille shutter assembly 120 in a manner that optimizes cooling of the brake assembly 126 while also taking into account aerodynamic performance.

[0028] As described above, the state information 200 may be provided from sensors of the sensor network 160. Inputs from various components, such as acoustic information, moisture data, steering angle, vehicle speed, brake torque request, wheel speed, ride height, etc., may be included in the state information 200. At the same time, the route information 202 (or more generally, location information) may be used to determine whether various road sections may require significant braking along the route or in the near future. In this regard, the route information 202 may indicate downhill sections, winding roads, heavy traffic areas, altitude, trailer status, historical driver profile information / behavior, or any other road conditions that generally require increased braking activity along the route or in the near future path of the vehicle 110.

[0029] The controller 140 may receive the state information 200 and the route information 202 to infer, determine, or confirm a road segment classification, rating, or characterization regarding brake usage on the road segment. The classification, rating, or characterization may be used alone or in combination with other state information 200 to provide input to a thermal model 240 that determines a target temperature 242 that may be applicable for the road segment or a given time period. The target temperature 242 may define a temperature below which the brake assembly 126 may be considered sufficiently cooled such that additional cooling assistance is not required. If the brake assembly 126 (or a portion thereof) exceeds the target temperature 242, action may be taken to enhance or increase cooling of the brake assembly 126 by opening the grille shutter assembly 120, as described in more detail below.

[0030] In an exemplary embodiment, the thermal model 240 used to determine the target temperature 242 can take into account many different factors in calculating the target temperature 242. In this regard, for example, high payload, trailering, ambient temperature, altitude, inclined surfaces, etc. can provide input to the thermal model 240 to determine the target temperature 242, as each can affect the heating or cooling rate of the components of the brake assembly 126. The thermal model 240 can also consider the rate of temperature change to predict future temperature peaks based on the current and expected rate of increase to change the target brake temperature at various intervals or when a specific stimulus or trigger condition is encountered. Thus, for example, the target temperature 242 can be set taking into account the derivative of the temperature rise, the distance away from the basic set point value originally used to determine the target temperature 242, or other real-time condition factors. In addition, in some cases, vehicle-to-vehicle communication (V2V) can be employed to share the temperature heating and cooling rates experienced at different locations, so that a vehicle approaching a given location can use information that another vehicle has encountered at the location to determine the target temperature 242 for the given location. Historical information associated with the same or other vehicles may also be used and may be weighted in the calculation of the thermal model 240 based on the age of the vehicle or based on other conditions similar to the current prevailing conditions. Thus, for example, if the weather was different, less weight may be given to the historical information, but if the weather conditions were substantially similar, more weight may be given to the historical information.

[0031] Among the state information 200 that may be provided to the controller 140, the current brake temperature of the brake assembly 126 (or a particular component thereof) may be included. The brake temperature may be an actual current temperature 250, which may be provided by a temperature sensor 252 disposed proximate each respective brake component (e.g., pad, shoe, caliper, drum, etc.) of the brake assembly 126 to measure such temperature. However, in some cases, as an alternative to measuring the actual temperature or as a backup, a temperature estimator 260 may be employed to provide an estimated current temperature 262. The temperature estimator 260 may employ a thermal model (e.g., similar to the thermal model 240) that estimates the actual temperature (rather than a target or destination temperature) for a given set of input conditions (e.g., obtained from the state information 200 and / or the route information 202). Thus, while the target temperature 242 defines a target or threshold temperature above which enhanced cooling is desired, the estimated current temperature 262 may use a model trained on actual data showing brake temperatures generated under a variety of different driving conditions.

[0032] Regardless of whether the current temperature value is the actual current temperature 250 or the estimated current temperature 262, the control algorithm 220 may use the current temperature value to determine how to control the shutter elements 230 of the grille shutter assembly 120. In this regard, for example, the control algorithm 220 may compare the current temperature value to the target temperature 242 to make a determination regarding control of the grille shutter assembly 120. Furthermore, in some cases, a plurality of different trigger, threshold, or set point temperature values ​​may be defined by the controller 140 via the control algorithm 220 for various different corresponding actions. Based on the determinations made, the control algorithm 220 may then generate a control instruction 270 to reposition the grille shutter assembly 120.

[0033] In an exemplary embodiment, the control algorithm 220 may include a table of values ​​or positions of the shutter elements 230, where the table is entered using specific vehicle parameters (e.g., speed, brake torque, current brake temperature, road segment characterization, loading information, altitude, etc.). Various other vehicle parameters may be entry values ​​in such a table, or may be weighting factors or correction factors for the table entry values ​​or the resulting values ​​or positions of the shutter elements 230. For example, ride height, yaw rate, tire age, wheel diameter, vehicle weight, etc. may be correction factors in the manner described above. The calculation may also take into account various vehicle state conditions (e.g., weight, weight distribution, passengers, load, fuel state, tire condition, etc.) and weather conditions (e.g., ambient external vehicle temperature, wet road, icy road, etc.) to tailor the treatment to the conditions of the road surface at any given time. In addition, the control algorithm 220 may include an iterative strategy for achieving the target settings in real time.

[0034] In some embodiments, the control algorithm 220 may reference a reference table 280 that may include correction factors to be applied to temperature estimates (rather than actual temperature measurements). The reference table 280 may include corrections based on any state information 200 that may be provided, or may be fixed values ​​that provide a buffer against the possibility that the estimates made by the temperature estimator 260 may be inaccurate. However, in some embodiments, the reference table 280 may also (or alternatively) be used to record data for applying machine learning to obtain better system performance over time. Thus, for example, a neural network or other machine learning module may be employed in conjunction with the reference table 280 to allow the estimates of the temperature estimator 260 to improve over time, particularly if actual data can be compared to the estimates over time to improve the accuracy of the model performance over time.

[0035] Figure 3 Shows Figure 11. A perspective view of a potential embodiment of a vehicle 110. In this regard, the vehicle 110 can include a body 300 attached to a chassis of the vehicle 110. The front wheels 310 and the rear wheels 320 can be operably coupled to the chassis, and Figure 1 Grille portion 330 of grille shutter assembly 120 may be disposed at a portion of vehicle body 300 proximate to (and in front of) each respective one of front wheels 310 and / or rear wheels 320. In some cases, grille portion 330 may conform to vehicle body 300 and direct air toward shutters (e.g., shutter elements 230) in respective passages, which further direct air toward respective brake components of brake assembly 126. Although Figure 3 Front wheels 310 and rear wheels 320 are shown each including an example of a grille portion 330 associated therewith, but in some cases only front wheels 310 or only rear wheels 320 may have brake cooling as described herein.

[0036] Figure 4 A block diagram illustrating operations that may be associated with a control algorithm of an exemplary embodiment is shown. In this regard, the vehicle may initially be turned on at operation 400, and it may be determined at operation 410 whether the vehicle is moving. If the vehicle is not moving (i.e., parked), the grille shutters may be fully opened at operation 420. In this regard, since the vehicle is not moving, airflow and cooling associated therewith may be allowed without any impact on vehicle aerodynamics. However, it should be understood that in some cases, it may be desirable to close the grille shutters even when not moving, such as when certain weather conditions exist. For example, if it is raining or snowing, it may be desirable to fully close the grille shutters when the vehicle is not moving (and may also move) if, for example, the brakes are not above a calibrated threshold temperature. At the same time, if the vehicle is moving, a balanced consideration of cooling and aerodynamics may be achieved, and at operation 430, a target brake temperature may be determined for vehicle conditions (e.g., as indicated by the state information 200 and the route information 202). The estimated or actual current temperature may be measured at operation 440, and then a determination may be made as to whether the current brake temperature (estimated or actual) is greater than the target brake temperature at operation 450. If the current brake temperature is not greater than the target brake temperature, then increased cooling via airflow directed to the brake system components may not be required, and the flow may return to operation 440. However, if the current brake temperature is greater than the target brake temperature, then some measure may be required to increase cooling.

[0037] Therefore, at operation 460, another determination may be made in comparing the current brake temperature to another threshold or set point, which in this case may be a fully open temperature set point. If the current brake temperature is not above the target brake temperature and the fully open temperature at operation 460, the grille shutters may be partially opened to reduce the current brake temperature below the target brake temperature at operation 470. After operation 470, the process may return to operation 440.

[0038] Conversely, if the current brake temperature is higher than the target brake temperature and the fully open temperature, it may be further determined at operation 480 whether the temperature is also higher than the maximum desired temperature. The maximum desired temperature may be a value within a buffer of the maximum design temperature of the corresponding brake component. If the temperature is not higher than the maximum desired temperature, the shutters may remain fully open at operation 490 before the process returns to operation 440 to continue monitoring. However, if the current brake temperature is higher than the maximum desired temperature, the friction brakes may be derated at operation 495. De-rating of the friction brakes may effectively mean placing a bias in the braking distribution that is typically made between friction sources and non-friction sources (e.g., regenerative braking) to reduce the use of friction brakes. This means that future braking torque requests will be more realized via non-friction (and therefore less heat-generating) braking methods.

[0039] As the vehicle 110 approaches its final destination (e.g., a geo-fenced area around the final destination or within a given distance of the final destination), it may be desirable to initiate a different target temperature. In this regard, since the vehicle 110 may be parked soon, it may be desirable to increase cooling (and reduce brake temperature) before the vehicle 110 is parked and the parking brake is applied. Thus, in some cases, the target temperature 242 may be lowered as the final destination is approached (e.g., if known from the route information 202). Because the electromechanical brakes are sometimes also used as parking brakes, the brake shoes may need to be adjusted as the brakes cool to ensure that the parking brakes are properly set. By commanding a lower temperature prior to parking, the time that the vehicle 110 needs to wake up to monitor brake temperature and / or make brake adjustments associated with cooling components can be minimized or at least reduced. As described above, altitude may also affect the target temperature setting because cooling is slower at higher altitudes.

[0040] right Figure 4 Other modifications to the normal operation of the control algorithm 220 are possible. For example, the brake shutters may be opened preemptively when aggressive braking occurs, when approaching a winding road, when reaching a heavy traffic area, or when a large incline is encountered or about to be encountered, and before the temperature is allowed to increase to the target temperature 242.

[0041] Figure 5 A block diagram of a method for providing selective air cooling to a brake assembly of a vehicle is shown. The method may include receiving status information from a sensor network of the vehicle at operation 500, and determining a target temperature of a brake component of the brake assembly based on the status information at operation 510. The method may also include comparing a current brake temperature with the target temperature at operation 520, and controlling airflow for cooling the brake component via a positioning aerodynamic device based on the comparison of the current brake temperature and the target temperature at operation 530. In some cases, the target brake temperature may be determined based on a thermal model that determines the target temperature based on route information defining a future route of the vehicle. In an exemplary embodiment, the target brake temperature may be determined based on a thermal model that determines the target temperature based on status information including vehicle load information indicated by a ride height sensor. In some cases, controlling the airflow may include at least partially opening the aerodynamic device in response to the current brake temperature being above the target temperature, adjusting the degree of opening of the aerodynamic device to maintain the current brake temperature below the target temperature, and fully opening the aerodynamic device in response to the current brake temperature being above the target temperature and a fully opening threshold temperature. In an exemplary embodiment, controlling the air flow further includes biasing satisfaction of the brake torque request toward reducing use of the friction brakes in response to a current brake temperature being greater than a target temperature, a fully open threshold temperature, and a maximum desired temperature. In some cases, the current brake temperature may be an estimated current brake temperature generated based on a thermal model or an actual current brake temperature measured via a temperature sensor disposed proximate to the brake assembly.

[0042] Thus, a vehicle control system for a vehicle may be provided, and in some cases, the vehicle control system may be more specifically an aerodynamic control system and / or a brake temperature control system. The system may include a repositionable aerodynamic device disposed at a portion of the vehicle, the repositionable aerodynamic device being controllable to balance aerodynamic efficiency with brake cooling capacity. Further, in some cases, the system may include: a brake assembly for applying negative torque to a wheel of the vehicle; a grille shutter assembly for directing airflow over the brake assembly when open and preventing airflow toward the brake assembly when closed; and a controller for calculating a target brake temperature, the controller being operably coupled to the grille shutter assembly to control positioning of the grille shutter assembly based on a comparison of a current brake temperature with a target brake temperature.

[0043] The systems of some embodiments may include additional features, modifications, extensions, etc. to achieve further goals or enhance the performance of the system. Additional features, modifications, extensions, etc. may be added in any combination with each other. The following is a list of various additional features, modifications, and extensions, which may be added individually or in any combination with each other. For example, the current brake temperature may be an estimated current brake temperature generated based on a thermal model. In an exemplary embodiment, the thermal model may generate an estimated current brake temperature based on input state information, the input state information including friction brake torque request, vehicle speed, ambient temperature, wheel radius, and altitude. In some cases, the current brake temperature may be the actual current brake temperature measured via a temperature sensor disposed near the brake assembly. In an exemplary embodiment, a target brake temperature may be determined based on a thermal model. In some cases, the thermal model may determine the target brake temperature based on route information defining the future route of the vehicle. In an exemplary embodiment, the thermal model may determine the target brake temperature based on state information including vehicle load information indicated by a ride height sensor. In some cases, the vehicle load information may be indicated by a ride height sensor or a user input defining the towing state of the vehicle. In an exemplary embodiment, the brake assembly may include brakes at rear wheels of the vehicle, and the grille shutter assembly may include a grille disposed in a body portion proximate each respective one of the rear wheels of the vehicle and a movable shutter associated with each instance of the grille. In some cases, the controller may at least partially open the grille shutter assembly in response to a current brake temperature being higher than a target brake temperature. In an exemplary embodiment, the controller adjusts the degree to which the grille shutter assembly is opened to maintain the current brake temperature below the target brake temperature. In some cases, the controller may fully open the grille shutter assembly in response to the current brake temperature being higher than the target brake temperature and a fully open threshold temperature. In an exemplary embodiment, the controller may bias the implementation of the brake torque request toward using a different braking source in response to the current brake temperature being higher than the target brake temperature, the fully open threshold temperature, and the maximum desired temperature, which may generally reduce the use of friction brakes in some cases, or may be biased toward using other friction brakes in other cases. In an exemplary embodiment, the controller may employ machine learning to modify a control algorithm for determining a target brake temperature. In some cases, the target temperature may be modified based on proximity to a final location associated with the vehicle's route.

[0044] A person skilled in the art of the invention to which the present invention belongs who has benefited from the teachings presented in the foregoing description and the associated drawings will think of many modifications and other embodiments of the invention set forth herein. Therefore, it should be understood that the present invention is not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. In addition, although the foregoing description and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and / or functions, it should be understood that alternative embodiments may provide different combinations of elements and / or functions without departing from the scope of the appended claims. In this regard, for example, as may be set forth in some of the appended claims, combinations of elements and / or functions different from those explicitly described above are also contemplated. Where advantages, benefits, or solutions to problems are described herein, it should be understood that such advantages, benefits, and / or solutions may be applicable to some exemplary embodiments, but not necessarily to all exemplary embodiments. Therefore, any advantages, benefits, or solutions described herein should not be considered to be critical, necessary, or essential to all embodiments or embodiments claimed herein. Although specific terms are employed herein, they are used only in a general and descriptive sense, not for the purpose of limitation.

[0045] According to the present invention, a vehicle control system is provided, having: a brake assembly for applying negative torque to one or more wheels of the vehicle; a grille shutter assembly that directs airflow over the brake assembly when open and prevents airflow toward the brake assembly when closed; and a controller that calculates a target brake temperature and is operably connected to the grille shutter assembly to control positioning of the grille shutter assembly based on a comparison of a current brake temperature with the target brake temperature.

[0046] According to an embodiment, the current brake temperature is an estimated current brake temperature generated based on a thermal model.

[0047] According to an embodiment, the thermal model generates the estimated current brake temperature based on input state information including friction brake torque request, vehicle speed, ambient temperature, wheel radius and altitude.

[0048] According to an embodiment, the current brake temperature is an actual current brake temperature measured via a temperature sensor arranged close to the brake assembly.

[0049] According to an embodiment, the target brake temperature is determined based on a thermal model.

[0050] According to an embodiment, the thermal model determines the target brake temperature based on route information defining a future route of the vehicle.

[0051] According to an embodiment, the thermal model may determine the target brake temperature based on status information including vehicle load information indicated by a ride height sensor.

[0052] According to an embodiment, the vehicle load information is indicated by a ride height sensor or a user input defining a towing status of the vehicle.

[0053] According to an embodiment, the brake assembly includes brakes at rear wheels of the vehicle and the grille shutter assembly includes a grille disposed in a body portion proximate each respective one of the rear wheels of the vehicle and a movable shutter associated with each instance of the grille.

[0054] According to an embodiment, the controller at least partially opens the grille shutter assembly in response to the current brake temperature being greater than the target brake temperature.

[0055] According to an embodiment, the controller adjusts the degree to which the grille shutter assembly is opened to maintain the current brake temperature below the target brake temperature.

[0056] According to an embodiment, the controller fully opens the grille shutter assembly in response to the current brake temperature being greater than the target brake temperature and a full-open threshold temperature.

[0057] According to an embodiment, the controller biases implementation of a brake torque request towards use of a different braking source in response to the current brake temperature being greater than the target brake temperature, the fully open threshold temperature, and a maximum desired temperature.

[0058] According to an embodiment, the controller employs machine learning to modify a control algorithm used to determine the target brake temperature.

[0059] According to an embodiment, the target brake temperature is modified based on a proximity to a final position associated with a route of the vehicle.

[0060] According to the present invention, a method for providing selective air cooling to a brake assembly of a vehicle is provided, the method comprising: receiving status information from a sensor network of the vehicle; determining a target temperature of a brake component of the brake assembly based on the status information; comparing a current brake temperature with the target temperature; and controlling an airflow for cooling the brake component via a positioning aerodynamic device based on the comparison of the current brake temperature and the target temperature.

[0061] In one aspect of the invention, the target brake temperature is determined based on a thermal model that determines the target temperature based on route information defining a future route of the vehicle or based on status information including vehicle load information indicated by a ride height sensor.

[0062] In one aspect of the invention, controlling the airflow includes at least partially opening the aerodynamic device in response to the current brake temperature being above the target temperature, adjusting the degree of opening of the aerodynamic device to maintain the current brake temperature below the target temperature, and fully opening the aerodynamic device in response to the current brake temperature being above the target temperature and a fully opening threshold temperature.

[0063] In one aspect of the present invention, controlling the air flow further comprises biasing implementation of a brake torque request toward use of a different braking source in response to the current brake temperature being greater than the target temperature, the fully open threshold temperature, and a maximum desired temperature.

[0064] In one aspect of the present invention, the current brake temperature is an estimated current brake temperature generated based on a thermal model or an actual current brake temperature measured via a temperature sensor disposed close to the brake assembly.

Claims

1. A vehicle control system, the system comprising: a brake assembly for applying negative torque to one or more wheels of the vehicle; a grille shutter assembly that directs airflow over the brake assembly when open and prevents airflow toward the brake assembly when closed; as well as A controller calculates a target brake temperature and is operably coupled to the grille shutter assembly to control positioning of the grille shutter assembly based on a comparison of a current brake temperature to the target brake temperature.

2. The system of claim 1 , wherein the current brake temperature is an estimated current brake temperature generated based on a thermal model, the thermal model generating the estimated current brake temperature based on input state information, the input state information including friction brake torque request, vehicle speed, ambient temperature, wheel radius, and altitude. 3 . The system of claim 1 , wherein the current brake temperature is an actual current brake temperature measured via a temperature sensor disposed proximate to the brake assembly, and wherein the target brake temperature is determined based on a thermal model.

4. The system of claim 3, wherein the thermal model determines the target brake temperature based on route information defining a future route of the vehicle, or wherein the thermal model determines the target brake temperature based on state information including vehicle load information indicated by a ride height sensor. 5 . The system of claim 4 , wherein the vehicle load information is indicated by a ride height sensor or a user input defining a towing status of the vehicle.

6. A system according to any preceding claim, wherein the brake assembly comprises brakes at the rear wheels of the vehicle, and Wherein the grille shutter assembly includes a grille disposed in a body portion proximate each respective one of the rear wheels of the vehicle and a movable shutter associated with each instance of the grille. 7 . The system of any preceding claim, wherein the controller at least partially opens the grille shutter assembly in response to the current brake temperature being greater than the target brake temperature.

8. The system of claim 7 , wherein the controller adjusts the degree of opening of the grille shutter assembly to maintain a current brake temperature below a target brake temperature, or wherein the controller fully opens the grille shutter assembly in response to the current brake temperature being above the target brake temperature and a full opening threshold temperature. 9 . The system of claim 8 , wherein the controller biases implementation of a brake torque request toward using a different braking source in response to the current brake temperature being greater than the target brake temperature, the fully open threshold temperature, and a maximum desired temperature. 10 . The system of claim 8 , wherein the controller employs machine learning to modify a control algorithm used to determine the target brake temperature.

11. A system as claimed in any preceding claim, wherein the target brake temperature is modified based on a proximity to a final position associated with a route of the vehicle.

12. A method of providing selective air cooling to a brake assembly of a vehicle, the method comprising: receiving status information from a sensor network of the vehicle; determining a target temperature of a brake component of the brake assembly based on the status information; comparing a current brake temperature with the target temperature; as well as Based on a comparison of the current brake temperature and the target temperature, airflow for the cooled brake component is controlled via positioning aerodynamic devices.

13. The method of claim 12, wherein the target temperature is determined based on a thermal model, the thermal model determining the target temperature based on: Route information defining a future route for the vehicle or the status information including vehicle load information indicated by a ride height sensor.

14. The method of claim 12, wherein controlling the airflow comprises at least partially opening the aerodynamic device in response to the current brake temperature being above the target temperature, adjusting the degree of opening of the aerodynamic device to maintain the current brake temperature below the target temperature, and fully opening the aerodynamic device in response to the current brake temperature being above the target temperature and a fully opening threshold temperature, and Wherein controlling the airflow further comprises biasing implementation of a brake torque request toward use of a different braking source in response to the current brake temperature being greater than the target temperature, the fully open threshold temperature, and a maximum desired temperature. 15 . The method of claim 12 , wherein the current brake temperature is an estimated current brake temperature generated based on a thermal model or an actual current brake temperature measured via a temperature sensor disposed proximate to the brake assembly.

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