Patent Publication Number: US-2019180623-A1

Title: Collision prediction method and device

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a collision estimation technology, particularly to a collision prediction method and a device thereof. 
     Description of the Related Art 
     Being a transporter, the vehicle has played an important and indispensable role in daily living. Although vehicles are efficient and convenient in traffic, they also have defects. Vehicles running fast may collide with each other and bring about serious traffic accidents. Traffic accidents may be caused by natural factors or human factors. However, most traffic accidents are caused by human factors. Therefore, controlling the human factors can prevent a running vehicle from colliding with another vehicle or pedestrians and decrease the number of traffic accidents effectively. 
     Thus, the devices able to detect the barrier before a vehicle, measure the distance between the barrier and the vehicle, and warn the driver of the barrier have been developed successively. The detection devices most frequently used to predict the front barrier are the distance sensor (such as a radar) or the image sensor. The distance sensor is used to detect a barrier in a single direction. The image sensor can be used to detect barriers in a wide angle. The abovementioned sensors can assist the driver in grasping the status of the vehicle and the distance between the barrier and the vehicle. The abovementioned sensors can cooperate with an alert system to avoid collision. 
     In addition to the abovementioned distance sensor and image sensor, the global positioning system (GPS) can also be used to detect the distance between the vehicle and the barrier. However, some factors may hinder GPS from detecting barriers, such as the weather or shelters. Thus, the application thereof is limited. 
     No matter whether the distance sensor, the image sensor or the GPS system is used, the acquired distance between the vehicle and the barrier can only be used to calculate the collision point of the vehicle and the barrier. However, instable signals may result in errors of the acquired distance. Further, the range of the collision point is very small. Thus, the output collision point is likely to deviate. Therefore, the position of the collision point has high uncertainty. 
     Accordingly, the present invention proposes a collision prediction method and a device thereof to overcome the abovementioned problems. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a collision prediction method and device, which can estimate the collision point of a first vehicle and a second vehicle and uses the collision point, the dimensions of the second vehicle, and the spatial error to predict the collision area, whereby to effectively increase the accuracy of predicting the collision area. 
     Another objective of the present invention is provide a collision prediction method and device, which can give the driver an alert, decelerate the vehicle or brake the vehicle according to the degree of risk, whereby to enhance driving safety. 
     In order to achieve the abovementioned objectives, the present invention proposes a collision prediction method, which comprises steps: a first vehicle receiving vehicular information of at least one second vehicle, wherein the vehicular information includes position, speed, direction and dimensions of the second vehicle; the first vehicle calculating a collision point of the first vehicle and the second vehicle according to the position, speed and direction of the second vehicle; the first vehicle generating a vehicular region with the collision point being a center, wherein the vehicular region spans double the length of the dimensions of the second vehicle along the direction of the second vehicle; and the first vehicle acquiring a global positioning system (GPS) offset, moving the vehicular region by the GPS offset to generate a movement range, and generating a collision area according to the movement range. 
     The present invention also proposes a collision prediction device, which is installed in a first vehicle and able to predict the probable collision area, and which comprises a communication device and a central processor. The communication device receives a GPS offset of the first vehicle and vehicular information of at least one second vehicle, wherein the vehicular information includes position, speed, direction and dimensions of the second vehicle. The central processor is electrically connected with the communication device to receive the vehicular information of the second vehicle. The central processor calculates a collision point of the first vehicle and the second vehicle according to the position, the speed and the direction. The central processor generates a vehicular region with the collision point being the center. The vehicular region spans double the length of the dimensions of the second vehicle along the direction of the second vehicle. The central processor acquires a global positioning system (GPS) offset through the communication device. The central processor moves the vehicular region by the GPS offset to generate a movement range and generates a collision area according to the movement range. 
     Below, embodiments are described in detail to make easily understood the objectives, technical contents, characteristics and accomplishments of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram schematically showing a collision prediction device according to one embodiment of the present invention; 
         FIG. 2  is a flowchart of a collision prediction method according to one embodiment of the present invention; 
         FIG. 3  is a diagram schematically showing a collision point according to one embodiment of the present invention; 
         FIG. 4  is a diagram schematically showing how to determine a collision point according to one embodiment of the present invention; 
         FIG. 5  is a diagram schematically showing how to generate a vehicular region according to one embodiment of the present invention; 
         FIG. 6  is a diagram schematically showing how to generate a movement range according to one embodiment of the present invention; 
         FIG. 7  is a diagram schematically showing how to generate a collision area according to one embodiment of the present invention; and 
         FIG. 8  is a flowchart of an alert mechanism according to one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Refer to  FIG. 1  a block diagram schematically showing the system of a collision prediction device according to one embodiment of the present invention. The collision prediction device  1  of the present invention is installed in a first vehicle to predict the probable range of the collision between the first vehicle and a second vehicle. The collision prediction device  1  of the present invention comprises a communication device  10  and a central processor  12 . The communication device  12  may be a wireless communication device or an Internet communication device, which can persistently receive external information from other vehicles, including the positions, speeds, directions and dimensions of other vehicles. The communication device  10  includes a GPS (Global Positioning System) receiver (not shown in the drawing) to receive GPS information and acquire the position GPS offset of the first vehicle. The central processor  12  is electrically connected with the communication device  10  to acquire the information received by the communication device  10 . The central processor  12  is also electrically connected with a vehicular information sensor  18 . The vehicular information sensor  18  includes a direction sensor (not shown in the drawing), a speed sensor (not shown in the drawing), etc. The central processor  12  receives the vehicular information sensed by the vehicular information sensor  18 , such as the direction, speed, etc. of the first vehicle. Thereby, the central processor  12  can predict the area of collision between the first vehicle and the second vehicle, using vehicular information, such the position, direction, speed, etc. of the first vehicle, and the vehicular information of the second, which is received by the communication device  10 . The central processor  12  can further use the area of collision to predict the time of collision and then sends out an alert or undertake other treatments. The alert device  14  is electrically connected with the central processor  12  and controlled to send out an alert by the central processor  12 . The automatic driving device  16  is electrically connected with the central processor  12  and controlled by the central processor  12  to undertake deceleration or braking. 
     Refer to  FIG. 1  again. The communication device  10  receives the vehicular information of the second vehicle from a vehicular computer system  20  installed in the second vehicle. The vehicular computer system  20  comprises a processor  22 , a transceiver  24 , and a vehicular information sensor  26 . The processor  22  records the dimensions of the second vehicle and is electronically connected with the transceiver  24 . The transceiver  24  may be an Internet transceiver. The processor  22  controls the transceiver  24  to transmit information to the communication device  10 . The transceiver  24  includes a GPS receiver (not shown in the drawing) to receive GPS signals and transfer the GPS signals to the processor  22 . Thus, the processor  22  acquires the current position of the second vehicle. The processor  22  is also electrically connected with the vehicular information sensor  26 . The vehicular information sensor  26  includes a direction sensor (not shown in the drawing) and a speed sensor (not shown in the drawing). The processor  22  controls the vehicular information sensor  26  to sense the direction and speed and acquires vehicular information of the second vehicle, such as the dimensions, speed, direction and position of the second vehicle. The processor  22  uses the transceiver  24  to transmit the acquired vehicular information to the collision prediction device  1 . 
     After the structure of the system, which the method of the present invention applies to, has been described above, the method of the present invention will be described below. Refer to  FIG. 1  and  FIGS. 2-7 . In this embodiment, the method of the present invention is used to predict the probable area of collision for vehicles heading for different directions in an intersection of roads. In Step S 10 , the collision prediction device  1  is installed a first vehicle  30  and uses the communication device  10  to receive the vehicular information transmitted by the vehicular computer systems  20  of a second vehicle  40 , which is heading for a direction different from that of the first vehicle  30  in the intersection of roads. The vehicular information includes the position, speed, direction and dimensions of the second vehicle  40 . Next, the process proceeds to Step S 12 . Refer to  FIG. 3 . The central processor  12  of the first vehicle  30  works out a collision point C of the first vehicle  30  and the second vehicle  40  using the positions, speeds, and directions of the first vehicle  30  and the second vehicle  40 . In the method of calculating the collision point of the first vehicle  30  and the second vehicle  40 , transform the positions of the first vehicle  30  and the second vehicle  40  into planar coordinates firstly. Next, extend a straight line A along the direction of the first vehicle  30  from the positional coordinates of the first vehicle  30 , and extend a straight line B along the direction of the second vehicle  40  from the positional coordinates of the second vehicle  40 , as shown in  FIG. 4 . The straight line A and the straight line B intersect at an intersection point to form a triangle, and the intersection point is exactly the collision point C. Next, work out the distance between the first vehicle  30  and the second vehicle  40  using the positional coordinates of the first vehicle  30  and the second vehicle  40 , which have been acquired beforehand. As the collision point C, the first vehicle  30 , and the second vehicle  40  form a triangle, the interior angle of the collision point C can be worked out according to trigonometry. The distance between the first vehicle  30  and the second vehicle  40  can be used to work out the distance between the first vehicle  30  and the collision area (BDM) according to the sine law. 
     After the collision point C is worked out, the process proceeds to Step S 14 . Refer to  FIG. 5 . In Step S 14 , the central processor  12  of the first vehicle  30  creates a vehicular region D with the collision point C being the center. The vehicular region D spans double the length of the dimensions of the second vehicle  40  along the direction of the second vehicle  40 . Next, the process proceeds to Step S 16 . Refer to  FIG. 6 . The central processor  12  generates a movement range E for the vehicular region D according to the GPS offset received by the communication device  10 . Refer to  FIG. 7 . Next, the central processor  12  generates a collision area F according to the movement range E. 
     After the collision area F is worked out, the process proceeds to Step S 18 . The central processor  12  estimates the time of collision between the first vehicle  30  and the collision area F, determines the degree of risk according to the time of collision, and undertakes the corresponding treatment according to the degree of risk. 
     In detail, the closer the vehicle to the collision area, the shorter the collision time (the time interval between now and collision). In this embodiment, the level-1 alert time (the collision time of the level-1 alert) is set to be longer than the level-2 alert time (the collision time of the level-2 alert), and the level-2 alert time is set to be longer than the level-3 alert time (the collision time of the level-3 alert). Then, the level-1, level-2, level-3 alert times are respectively corresponding to the risks from a low degree to a high degree. Refer to  FIG. 7  and  FIG. 8 . The process of determining the degree of risk and the corresponding treatment includes Steps S 180 - 189 . In Step S 180 , estimate how much time later the collisions will take place between the first vehicle  30  and the front end G 1  and the rear end G 2  of the collision area F, which face the first vehicle  30 , to generate a front end collision time and a rear end collision time. The front end collision time and the rear end collision time are calculated according to a collision time equation: 
     
       
         
           
             
               t 
               BDM 
             
             = 
             
               
                 BDM 
                 
                   V 
                   B 
                 
               
               ± 
               
                 ERROR 
                 
                   V 
                   B 
                 
               
             
           
         
       
     
     wherein t BDM  is the front end collision time or the rear end collision time; V B  is the speed of the first vehicle; BDM is the distance between the first vehicle and the front end or rear end of the collision area. 
     After the front end or rear end collision time is acquired, the process proceeds to Step S 182 . In Step S 182 , the central processor  12  determines whether one of the front end collision time and the rear end collision time is shorter than the level-1 alert time. If no, the process returns to Step S 180  and continues to estimate the front end collision time and the rear end collision time. If yes, the process proceeds to Step S 184 . In Step S 184 , the central processor  12  controls the alert device  14  to generate an alert to remind the driver. In one embodiment, the alert device  14  is a display device presenting an alert image to remind the driver of the probable collision. In one embodiment, the alert device is an audio device generating an alert sound to remind the driver. 
     After the alert signal is sent out, the process proceeds to Step S 185 . In Step S 185 , the central processor  12  determines whether one of the front end collision time and the rear end collision time is shorter than the level-2 alert time. If no, the process returns to Step S 180  and continues to estimate the front end collision time and the rear end collision time. If yes, it indicates that the first vehicle  30  becomes more close to the collision area F, and the process proceeds to Step S 186 . In Step S 186 , the central processor  12  sends a deceleration signal to the automatic driving device  16 , and the automatic driving device  16  undertakes deceleration according to the deceleration signal. Next, the process proceeds to Step S 188 . In Step S 188 , the central processor  12  determines whether one of the front end collision time and the rear end collision time is shorter than the level-3 alert time. If no, the process returns to Step S 180  and continues to estimate the front end collision time and the rear end collision time. If yes, it indicates that the first vehicle  30  becomes further more close to the collision area F, and the process proceeds to Step S 189 . In Step S 189 , the central processor  12  sends a braking signal to the automatic driving device  16  to directly brake the first vehicle  30 . According to the abovementioned classification of risks, the present invention reminds the driver of probable collision while the vehicle  30  is approaching the collision area F firstly; if the driver does not decelerate the first vehicle  30  but let the first vehicle  30  further approach the collision area F, the present invention controls the automatic driving device  16  to decelerate or brake the first vehicle  30 . Therefore, the present invention can effectively prevent collision and enhance driving safety. 
     In conclusion, the present invention can estimate the collision points of this vehicle and another vehicle, and estimate the collision area according to the collision points, the dimensions of another vehicle, and spatial error. Therefore, the present invention can increase the accuracy of predicting the collision area. Further, the present invention can give the driver an alert, decelerate the vehicle, or brake the vehicle according to the degree of risk. Therefore, the present invention can effectively enhance driving safety. 
     The embodiments described above are only to exemplify the present invention but not to limit the scope of the present invention. Any equivalent modification or variation according to the characteristic or spirit of the present invention is also to be included by the scope of the present invention.