Patent Publication Number: US-9845092-B2

Title: Method and system for displaying probability of a collision

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. Provisional Application No. 61/951,094 filed Mar. 11, 2014. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to automotive vehicles, and more particularly to driver assistance systems for automotive vehicles. 
     BACKGROUND 
     Advancements in available sensor technology have led to the ability to improve safety systems for vehicles. Arrangements and methods for detecting and avoiding collisions are becoming available. Such driver assistance systems use sensors located on the vehicle to detect an impending collision. The systems may warn the driver of various driving situations to prevent or mitigate collisions. Additionally, sensors and cameras are used to alert the driver of possible obstacles when the vehicle is traveling in reverse. Such systems are especially useful for increasing safety in vehicles that operate under autonomous or semi-autonomous conditions. 
     The background description provided herein is for generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
     SUMMARY 
     A disclosed method of assisting in the maneuvering of a vehicle includes the steps of determining a scalar field representing the probability of collision with an object at various locations proximate to the vehicle with a controller located within the vehicle. The probability of collision is determined based on information received indicative of the proximity of the object to the vehicle, and the field of collision probability is displayed with a visual representation to an operator of the vehicle. 
     A disclosed maneuver assistance system for a vehicle includes a controller including a first portion receiving information indicative of vehicle motion, a second portion receiving information indicative of the proximity of an object to the vehicle, and a third portion for generating a scalar field representing the probability of collision at various locations proximate to the vehicle based on the information indicative of vehicle motion and the proximity of an object to the vehicle. The controller generates a signal used by a display to generate a visual representation of the probability of collision with the object to enable communication of the probability of collision to an operator of the vehicle. 
     Although the different examples have the specific components shown in the illustrations, embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from one of the examples in combination with features or components from another one of the examples. 
     These and other features disclosed herein can be best understood from the following specification and drawings, the following of which is a brief description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a schematic illustration of a top view of a vehicle utilizing a disclosed maneuver assistance system; 
         FIG. 2  is a schematic illustration of an example controller of the maneuver assistance system; 
         FIG. 3  is a schematic illustration of possible object and vehicle paths predicted by the example maneuver assistance system; 
         FIG. 4  is a graphical illustration of a two-dimensional image illustrating a visual depiction of a field of collision probability; 
         FIG. 5  is a graphical illustration of a two-dimensional image illustrating another visual depiction of a field of collision probability; 
         FIG. 6  is a graphical illustration of a field of collision probability overlaid on a rear-view camera image; 
         FIG. 7  is another graphical illustration of a two-dimensional image illustrating a visual depiction of a field of collision probability for an object outside of the vehicle path; 
         FIG. 8  is another graphical illustration of a field of collision probability overlaid on a rear-view camera image; 
         FIG. 9  is a graphical illustration of a three-dimensional image illustrating a field of collision probability for an object within the vehicle path. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses. For purposes of clarity, the same reference numbers will be used in the drawings to identify similar elements. 
     Referring to  FIG. 1 , a vehicle  10  includes a driver assistance system  15 . The driver assistance system  15  includes a controller  18  and display  22  within the vehicle cabin. The display  22  is viewable by a vehicle operator. The controller  18  receives information indicative of vehicle motion and the proximity of an object  34 , and then generates a visual representation on the display  22  for communicating the probability of a collision with the object  34  at various locations behind the vehicle. 
     The example vehicle  10  further includes an automatic braking system  12  (schematically shown) that may be used to stop or slow the vehicle  10  during autonomous and/or semi-autonomous vehicle operations. In particular, the automatic braking system  12  may be used when the vehicle  10  is performing a reverse driving operation. Throughout this specification, the relative forward and reverse directions are in reference to the direction that an operator for the vehicle  10  would primarily be facing when operating the vehicle  10 . 
     The driver assistance system  15  and the automatic braking system  12  may be used along with other safety systems, such as a reverse collision avoidance system  14  and an electronic brake system (EBS)  16 . The controller  18  may be used for all of the systems  12 ,  14 ,  15  and  16 , or each system  12 ,  14 ,  15 , and  16  may have a separate controller that can communicate with each of the others. Moreover, the controller  18  may be part of an overall vehicle controller that governs all vehicle operations. 
     Referring to  FIG. 2  with continued reference to  FIG. 1 , the controller  18  includes a first portion  20  for receiving information indicative of vehicle motion. The information indicative of vehicle motion is provided from an input  28  that includes signals from sensors disposed within the vehicle  10 . The controller  18  includes a second portion  26  receiving information indicative of the proximity of an object to the vehicle and other characteristics of that object, such as velocity and classification. A third portion  24  of the controller  18  generates a scalar field representing the probability of collision at various locations proximate to the vehicle based on information indicative of vehicle motion and proximity of the object. The controller  18  uses the probability determination to generate an output signal  25  that directs the display  22  to generate a visual representation of the scalar field representing the probability of collision and communicate this information to the operator of the vehicle. 
     The probability of collision is used to determine a value such as a collision confidence number to determine the likelihood of a collision. The more likely a collision with the object  34  the higher the value of the collision confidence number. If the probability of collision exceeds a predetermined threshold, the controller  18  can communicate that at least one vehicle collision avoidance action may be required. The required action can include issuing a warning to a driver when an object is detected and/or actuating the automatic braking system  12  to slow or stop the vehicle. 
     The display device  22  installed within the vehicle  10  generates a visual representation of the surrounding environment for viewing by the driver. The visual representation can include a two-dimensional or three-dimensional rendering of the collision probability for locations proximate to the vehicle, given the detected position of an object  34 . 
     The vehicle  10  includes proximity sensors  36  and cameras  30 A-D that provide the input  28  to the controller  18 . It should be understood that the proximity sensors  36  and the cameras  30 A-D are only an example combination of sensors that could be utilized to provide information to the disclosed maneuver assistance system  15 . The cameras  30 A-D may be monocular cameras, binocular cameras, or another type of sensing device capable of providing a view of the future path of the vehicle  10 . The cameras  30 A-D are mounted to the sides, front and rear of the vehicle such that an image of the complete environment surrounding a vehicle can be obtained and generated. 
     In addition to the cameras  30 A-D, the system  15  may use other systems and sensors to assist in identifying objects  34 . Such systems and sensors may include, but are not limited to, proximity sensors  36 , LiDAR, radar, ultrasonic sensors, GPS  38 , radio sensors, etc. Furthermore, other sensors that can provide information indicative of vehicle operation and proximity of objects surrounding the vehicle  10  are within the contemplation of this disclosure. 
     Referring to  FIG. 3  with continued reference to  FIG. 1 , the controller  18  includes an algorithm that performs a probabilistic analysis of sensor-reported objects, including stationary objects and moving pedestrians, expected and/or possible motion of detected pedestrians, and expected and/or possible driver input. The current vehicle path and potential driver input is utilized to predict a range of potential vehicle paths. 
     The probabilistic analysis includes generating a predictive model of possible vehicle paths  40  and a predictive model of possible object paths  42 . The predicted vehicle paths  40  include the expectation that the vehicle will continue along its current path as is shown schematically by  46 A, but also account for the fact that the driver may turn the vehicle  10  such that it proceeds along an alternate path such as is schematically indicated at  46 B,  46 C and  46 D. 
     Similarly, the positional uncertainty of the object expands over time, as illustrated by  42 . The predicted position of the object  34  at a given point in time can be a function of object characteristics such as current position and velocity. For each successive future time, the actual location of the object  34  may be in an ever-increasing range of possible locations. From the initial position of the object  32 , a predictive model is generated for possible locations of the object  42  relative to possible vehicle paths  40 . 
     The predictive model of the vehicle path  40  and the predictive model of the object path  42  are combined to identify possible intersecting points that are indicative of a collision. The joint probability of the vehicle path sample and object path sample are used to determine the probability of collision for each intersecting point. The set of all such intersecting points comprises the field of collision probability that is visualized for the driver. 
     Referring to  FIG. 4 , the disclosed system provides for the display  22  to generate a visual representation of the determined field of collision probability as was illustrated by  FIG. 3 . The display  22  provides a visual indication to the driver of each location where the collision probability is non-zero or greater than a predetermined threshold value. The information is communicated by changes in color and opacity, and the visualization is updated as the vehicle moves or the environment changes. The displayed images account for the current path of the vehicle, taking into account the vehicle&#39;s current gear (forward and reverse), speed and steering angle. 
     In the example illustrated in  FIG. 4 , the probability of a collision is indicated by the variations in color attributes such as hue, saturation, luminosity or opacity, as indicated by  45 A-D. The shaded area indicated at  45 A is brightest and corresponds to the greatest probability of collision. The shaded area  45 D is darker and indicates a lesser probability of collision. The intermediate shaded areas  45 B and  45 C indicate respective levels of collision probability that are displayed to the vehicle operator. 
       FIG. 4  is a simple two-dimensional visual representation that illustrates a predicted vehicle path  40  with the probability of collision at various locations represented by the shaded areas  45 A-D. The visual representation provided to the driver can correspond with the actions taken by the collision avoidance system  14  to provide greater awareness and understanding of system interventions to the driver. 
     Referring to  FIGS. 5 and 6 , the vehicle  10  is shown schematically along with the predicted path  40 . A detected object  34  is represented by a range of color variations that progressively become brighter as the probability of collision increases.  FIG. 5  illustrates the field of collision probability relative to the predicted vehicle paths.  FIG. 6  is an example view that might be generated by the display  22  that overlays the predicted path  40  and field of collision probability  45  on an image generated by one of the cameras  30 D. Variations in the probability of collision are represented by the different colors or shading  45 A-D. The view provided by the display  22  serves to communicate the probability information through the shading  45 A-D and thereby inform the driver of potential collision risks. The lower the probability of collision, the lighter or more transparent the collision probability overlay. 
     As appreciated, the example disclosed in  FIG. 6  is straightforward as the object  34  is stationary and within the view of the camera  30 D and therefore is visible within the display. However, the example maneuver assistance system  15  could also detect objects  34  that may be outside of the camera field of view and generate a color variation in regions with non-zero collision probability to inform the driver of potential collision risks. 
     Referring to  FIGS. 7 and 8 , an object  34  is shown that is outside of the current vehicle path  46 A. Since the driver could modify the current vehicle trajectory and the object could change its position, there is still a non-zero probability of collision at locations marked by the shaded areas  45 A-D. The majority of the area bounded by the current vehicle path  46 A is not shaded, which indicates no risk of a collision. However, the shaded regions  45 A-D have a non-zero probability of collision and help to inform the vehicle operator of potential collision risks, even when that collision risk is not visibly obvious. In such a case, the operator of the vehicle could respond by modifying the vehicle&#39;s trajectory to reduce the collision risk and increase safety. 
     Although the examples illustrated in  FIGS. 5-8  include objects that are stationary, the example system  15  can also generate a visual representation of the probability of collision for moving objects, even when the objects are not currently within the field of view of the camera  30 D. 
       FIG. 9  shows an example of how a three-dimensional (3-D) rendering could be used to depict the probability of collision. Like the shading  45 A-D shown in  FIGS. 5-8 , the plots indicated by  48 A-D show how a third dimension can be used to visually represent the probability of a collision. The 3-D representation provides a unique perspective to the driver that can be actively modified based on driver actions or changes in the environment. This active modification results in an immediate update of the collision probability rendering such that the driver can have a better and more thorough understanding of how different actions affect the risk of collision with a detected object. 
     It should be appreciated that many different display highlighting techniques and formulations are within the contemplation of this disclosure for communicating potential collision probability in view of a current predicted vehicle path. 
     Accordingly, the example system  15  utilizes predictive models of both the vehicle path  40  and a detected object path  42  to determine a probability of collision that is visually represented on the display  22  that enables the driver to take preventative measures to avoid collisions. 
     While the best modes for carrying out the disclosed system have been described in detail, the true scope of the disclosure should not be so limited, since those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.