PATENT ABSTRACT
A vehicle includes a parking assist system that identifies an inclination of the vehicle and an angle of wheels relative to a centerline of the vehicle. The vehicle also includes a controller that, in response activation of the vehicle, the inclination exceeding a first threshold, and the angle exceeding a second threshold, adjusts the angle to center the wheels relative to the centerline.

PATENT DESCRIPTION
TECHNICAL FIELD 
       [0001]    The present disclosure relates to parking assist systems for vehicles. 
       BACKGROUND 
       [0002]    When a vehicle is parked on a hill, a driver may angle the wheels in a certain direction to prevent the vehicle from rolling. For example, the front wheels of the vehicle may be angled away from the curb if the vehicle is facing uphill, toward the curb if the vehicle is facing downhill, or to the right if no curb is present. 
       SUMMARY 
       [0003]    A parking assist system for a vehicle includes a controller configured to, in response to activation of the vehicle and data indicating that an inclination of the vehicle exceeds a first threshold and a steering angle of the vehicle exceeds a second threshold, adjust the steering angle to center wheels of the vehicle. 
         [0004]    A vehicle includes a parking assist system configured to identify an inclination of the vehicle and an angle of wheels relative to a centerline of the vehicle, and a controller configured to, in response activation of the vehicle, the inclination exceeding a first threshold, and the angle exceeding a second threshold, adjust the angle to center the wheels relative to the centerline. 
         [0005]    A control method for a parking assist system of a vehicle includes, in response to activation of the vehicle and data indicating a vehicle incline exceeding a first threshold and a steering angle exceeding a second threshold, adjusting by a controller the steering angle to center a set of wheels of the vehicle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic view of a vehicle parked on an inclined roadway; and 
           [0007]      FIG. 2  is a control logic flow diagram for centering the wheels of the vehicle after vehicle activation. 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments may take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures may be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations. 
         [0009]      FIG. 1  depicts a schematic view of a vehicle  10  parked on an inclined roadway  12 . The vehicle  10  includes a steering system  14  having a steering wheel  16 , an accelerometer  17 , an EPAS motor  18 , and a steering angle sensor  20  in communication with a controller  22 . The steering angle sensor  20  may include a pinion angle sensor, a steering wheel angle sensor, or any other sensor that may be configured to determine an angle of vehicle wheels  32 . Further, the vehicle  10  includes a parking assist system  21  to communicate, using near field communication, between the controller  22  and an activation transceiver  24 . While preferred, any other communication system may allow communication between the controller  22  and the activation transceiver  24 , such as but not limited to, Bluetooth, WiFi, dedicated short range communication, or in-vehicle networks. The activation transceiver  24  may start, or ignite a vehicle engine to allow the vehicle  10  to propel forward or deactivate the vehicle and turn off a vehicle engine in order to park the vehicle  10 . The controller  22  may also be in communication with a vehicle vision system  26  including a camera  27  or an ultrasonic sensor  29 , as well as a navigation system  25  and a map  23  to detect the presence of a curb  28 . Any other vehicle vision sensors may be used to communicate the presence of the curb  28  to the controller  22 . 
         [0010]    The inclined roadway  12  has an incline β. Incline β corresponds with a steering angle α. The steering angle α may be defined as an angle between the wheels  32  and a center  34  of the vehicle  10 . As incline β reaches a first threshold, the accelerometer  17  communicates that the incline β is above the first threshold to the controller  22 . The controller  22  uses the steering system  14  to account for the incline β of the roadway  12 . As by way of example, the steering system  14  uses the incline data from the controller  22  to activate the EPAS motor  18  to adjust the steering wheel  16  such that the steering angle α exceeds a second threshold. The steering system  14  may also be configured to adjust the steering angle α by angling the wheels  32  in vehicles without a steering wheel. The controller  22  may also use the accelerometer  17  to determine which direction the steering system  14  should adjust the wheels  32 . For example,  FIG. 1  depicts a scenario in which a front  30  of the vehicle  10  faces downhill and the incline β exceeds the first threshold. When a front  30  of the vehicle  10  faces downhill, the controller  22  instructs the steering system  14  to adjust the vehicle wheels  32  toward the curb  28  to achieve the steering angle α. Angling the wheels  32  toward the curb  28  when the front  30  of the vehicle  10  faces downhill allows the curb  28  to act as a stop, preventing the vehicle  10  from rolling downhill. Downhill may be defined when the front  30  of the vehicle  10  faces toward a decline  23  of a slope  25  of the inclined roadway  12 . 
         [0011]    While depicted in  FIG. 1 , the controller  22  may use the accelerometer  17  to account for similar scenarios. For example, if the controller  22 , using the accelerometer  17 , determines a front  30  of the vehicle faces uphill while the incline β of the roadway  12  still exceeds the first threshold, the controller  22  instructs the steering system  14  to adjust the vehicle wheels  32  away from the curb  28  to achieve the steering angle α. Angling the wheels  32  away from the curb  28  when the front  30  of the vehicle  10  faces uphill allows the curb  28  to prevent the vehicle  10  from rolling down the roadway  12 . Uphill may be defined when the front  30  of the vehicle faces toward an incline (not shown) of the slope  25  of the inclined roadway  12 . 
         [0012]    The controller  22  may angle the wheels  32 , using the steering system  14  as described above, when the activation transceiver  24  indicates the vehicle  10  is off and the steering angle sensor  20  indicates the wheels  32  are aligned with a center  34  of the vehicle  10 . This allows the steering system  14  to automatically adjust the wheels  32  to further park the vehicle  10  on the inclined roadway  12 . 
         [0013]    The controller  22  is also configured to use the steering system  14  to align the wheels  32  with the center  34  of the vehicle  10  when the activation transceiver  24  indicates vehicle activation. For example, when the parking assist system  21  indicates to the controller  22  that the distance between the activation transceiver  24  and the parking assist system falls below a third threshold, the controller will instruct the steering system  14  to align the wheels  32  with the center  34  of the vehicle. The third threshold may preferably be when the activation transceiver  24  is within a cabin (not shown) of the vehicle  10 . However, the parking assist system  21  may also indicate that the activation transceiver  24  is within the third threshold at a predetermined distance from the parking assist system  21 . The predetermined distance may be based on the range of near field communication systems. 
         [0014]    For example upon actuation of the activation transceiver  24 , the controller  22  receives input from the steering angle sensor  20  indicating that the wheels  32  have been angled at the steering angle α exceeding the second threshold and from the accelerometer  17  that the vehicle  10  is on the incline β exceeding the first threshold. The controller instructs the steering system  14  to actuate the EPAS motor  18  to turn the wheels  32 , based on the input from the steering angle sensor  20 , to align the wheels  32  with the center  34  of the vehicle  10 . Aligning the wheels  32  with the center  34  of the vehicle  10  prepares the vehicle  10  for road use. Further, the controller  22  may also instruct the steering system  14  to further adjust the steering angle α such that the wheels  32  are angled away from the curb  28  and toward the roadway  12  to prepare the vehicle  10  for road use. The parking assist system  21  may also be configured to send an input signal to the controller  22  indicating cancellation of the steering system  14  centering maneuver described above. 
         [0015]    For example, if the incline β exceeds the first threshold and the steering angle α exceeds the second threshold and the activation transceiver  24  is within the third threshold of the parking assist system  21  and indicates vehicle activation, but an operator (not shown) indicates that aligning the wheels  32  with the center  34  of the vehicle  10  may not be ideal, the operator may apply a brake  36  for the vehicle  10 . Applying the brake  36  alerts the controller  22  that centering the wheels  32  may not be necessary and the controller  22  may likewise instruct the steering system  14  to maintain the wheels  32  at the steering angle α. Likewise, the operator may grab the steering wheel  16  to alert the controller  22  that centering the wheels may not be necessary. 
         [0016]    Further, the steering system  14  may adjust the steering angle α to center the steering wheel  16  between vehicle activation and displacement of the brake  36 . This allows the parking assist system  21  to account for varying circumstances that may arise during operation of the vehicle  10 . Further, the controller  22  may also be configured to apply the brake  36  while the steering system  14  is aligning the wheels  32  with the center  34  of the vehicle. If the accelerometer  17  indicates that the incline β of the roadway  12  requires the brakes  36  be applied while the wheels  32  are centered, the controller  22  may likewise be configured to automatically apply the brakes  36  while the steering system  14  centers the wheels  32 . 
         [0017]    The controller  22  may also be configured to activate an alert  38  of the pending centering of the wheels  32  by the steering system  14 . In at least one embodiment, the alert  38  may be an audible tone or dialect indicating that the steering system  14  is aligning the wheels  32  with the center  34  of the vehicle  10 . The alert  38  may also include a visual indication of the maneuver, or by providing haptic feedback indicating the maneuver. The alert  38  allows the operator the opportunity to abort aligning the wheels  32  with the center  34  of the vehicle  10  as described above. The alert  38  ensures that the operator is aware of the maneuver by the steering system  14  and may be able to control the vehicle  10  if needed. 
         [0018]      FIG. 2  depicts control logic for the controller  22  to center the wheels  32  of the vehicle  10 . At  40 , the controller  22  determines if the activation transceiver is within range of the vehicle  10  or is sending data indicating vehicle activation. If at  40  the controller  22  does not receive data indicating vehicle activation from the activation transceiver, the control logic ends. If however at  40  the controller  22  does receive data indicating vehicle activation, the controller  22  uses the accelerometer to calculate the inclination of the roadway at  42 . The controller  22  uses the inclination data at  42  to determine if the vehicle inclination is greater than a first threshold at  44 . If the vehicle inclination is not greater than a first threshold at  44 , the control logic ends. If the controller  22  determines that the vehicle inclination is greater than the first threshold at  44 , the controller  22  may use the vision system, such as an ultrasonic sensor or camera to detect the presence of a curb  46 . 
         [0019]    The controller  22  then receives input, using the steering angle sensor  20 , of the wheel angle at  48 . The controller  22  uses the input of the steering angle at  48  as well as the presence of the curb at  46  to determine if the steering angle is greater than the second threshold at  50 . If the curb is present at  46  and the steering angle has been adjusted at  48  to account for the curb, the controller  22  may then determine at  50  if the wheels  32  have been sufficiently angled toward the curb, exceeding the second threshold. If at  50  the controller determines that the steering angle does not exceed the second threshold and the wheels  32  do not need to be centered, the control logic ends. If however the controller  22  determines at  50  that the steering angle exceeds second threshold, the controller  22  determines at  52  whether centering the wheels  32  using the steering system  14  should be canceled. For example, at  52  the controller  22  will determine if a brake pedal has been depressed, as described above. 
         [0020]    If at  52  the controller  22  determines that a brake pedal has been depressed, the controller  22  will activate the braking system at  54 . After activating the braking system at  54  the control logic ends. If, at  52 , the controller determines that a brake pedal has not been depressed, the controller  22  will adjust the steering angle, using the steering system  14 , to align the wheels  32  with the center of the vehicle  10  at  56 . While the controller  22  centers the wheels  32  with respect to the vehicle  10 , the controller  22  also will issue an alert of the centering at  58 . As stated above, issuing the alert of the centering at  58  further provides control and communication such that an occupant is aware of the adjustment at  56 . After the wheels  32  have been centered at  56  and the alert has been issued at  58  the control logic ends and the vehicle  10  is ready for travel. 
         [0021]    While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments may be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics may be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes may include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications.