Abstract:
The present invention is an automotive collision mitigation system comprising at least one sensor for sensing first and second detection zones. A controller, responsive to the at least one sensor, determines at least one countermeasure attribute for reducing occupant injury potential.

Description:
BACKGROUND OF INVENTION  
       [0001]     The present invention relates, generally, to the field of pre-crash sensing systems for automotive vehicles and, more specifically, to automotive pre-crash sensing methods and apparatuses having countermeasure attributes associated therewith.  
         [0002]     Auto manufacturers are investigating radar, lidar, and vision-based pre-crash sensing systems to improve occupant safety. Current vehicles typically employ accelerometers that measure decelerations acting on the vehicle body in the event of a crash. In response to the accelerometer measurements, braking, acceleration and other countermeasure systems are employed.  
         [0003]     In certain crash situations, it would be desirable to provide information about potential collisions before forces actually act upon the vehicle in order to manipulate the operation of the vehicle and thus, reduce the impact of a collision. One example where such a system would be beneficial is a situation involving a frontal and rear impact situation occurring at relatively the same incident.  
         [0004]     U.S. Pat. No. 6,105,507 for an amusement park ride attraction discloses a vehicle bumper system which utilizes front and rear sensors to allow a vehicle to accelerate or decelerate to simulate either a frontal or rear collision. A vehicle braking system and an acceleration system are controlled by a programmable controller for actuating the braking and accelerator systems in response to a simulated frontal or rear collision occurring in order to simulate the effects of a physical impact for amusement purposes.  
         [0005]     While U.S. Pat. No. 6,105,507 is suitable for its intended purpose for amusement park rides, it does not address mitigating the combined magnitude of potential dual collision events. It would be desirable to provide a system that takes into consideration the combined magnitude of the collision events in a dual pre-crash situation in order to deploy associated countermeasure attributes for mitigating the effects of multiple collisions.  
       SUMMARY OF INVENTION  
       [0006]     Briefly described, the present invention comprises a system, including apparatuses and methods that integrate a pre-crash sensor for sensing first and second detection zones with pre-crash sensor logic for the deployment of countermeasure attributes.  
         [0007]     More particularly, in a first form, the present invention provides an automotive collision mitigation system. In one aspect of the present invention, at least one sensor is provided for sensing a first detection zone and a second detection zone.  
         [0008]     A controller then determines at least one countermeasure attribute responsive to the at least one sensor.  
         [0009]     Therefore, the present invention applies pre-crash countermeasure attributes to reduce the combined magnitude of primary and secondary potential impacts on a vehicle for the purpose of reducing the potential for occupant injury.  
         [0010]     Other advantages of the present invention will become apparent upon reading and understanding the present specification when taken in conjunction with the appended drawings. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]     The invention will be more readily understood from a reading of the following specifications and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein:  
         [0012]      FIG. 1  displays a block diagram of an automotive collision mitigation system according to the present invention.  
         [0013]      FIG. 2  displays a dual pre-crash situation response according to the present invention.  
         [0014]      FIG. 3  displays a flowchart representation of pre-crash logic for a frontal primary impact according to the present invention.  
         [0015]      FIG. 4  displays a flowchart representation of pre-crash logic for a rear primary impact according to the present invention. 
     
    
       [0016]     The construction designed to carry out the invention will hereinafter be described, together with other features thereof.  
       DETAILED DESCRIPTION  
       [0017]     Referring now to the drawings in which like numerals represent similar elements or steps throughout the several views, a collision mitigation system is described herein. The collision mitigation system of the present invention comprises a controller that is electronically communicative with at least one object sensor. The controller determines an appropriate countermeasure for reducing the effects of a likely collision as a consequence of an object or objects sensed by the at least one object sensor.  
         [0018]     Referring to  FIG. 1 , a collision mitigation system  100  for a host vehicle  12  has a controller  14 . Controller  14  is preferably a microprocessor-based controller that is coupled to a memory  16  and a timer  18 . Memory  16  and timer  18  are illustrated as separate components from that of controller  14 . However, those skilled in the art will recognize that a memory  16  and timer  18  may be incorporated into controller  14 .  
         [0019]     Memory  16  may comprise various types of memory including read only memory, random access memory, electronically erasable programmable read only memory, and keep alive memory. Memory  16  is used to store various predefined thresholds and parameters as will be further described below.  
         [0020]     Timer  18  is a timer such as a clock timer of a central processing unit within controller  14 . Timer  18  is capable of timing the duration of various events as well as counting up or counting down.  
         [0021]     The present invention comprises at least one sensor for sensing a first detection zone and a second detection zone, as described in detail below. One embodiment of the present invention comprises frontal and rear object sensors. Frontal object sensor  20  is coupled to controller  14 . Frontal object sensor  20  may be comprised of one or more types of sensors including a radar  22 , a lidar  24 , and/or a frontal vision system  26 . Frontal vision system  26  may be comprised of one or more cameras  28 . The radar  22 , lidar  24 , and/or the one or more cameras  28  are capable of sensing the presence and the distance of an object from host vehicle  12  within a frontal detection zone, as described in detail below. Also, several radars or lidars may be used to determine the distance to an object using well-known triangulation techniques.  
         [0022]     Rear object sensor  30  is also coupled to controller  14 . Rear object sensor  30  may also be comprised of one or more sensors including radar  32 , lidar  34  and/or a rear vision system  36 . Rear vision system  36  may be comprised of one or more cameras  38 . The radar  22 , lidar  24 , and/or the one or more cameras  38  are capable of sensing the presence and the distance of an object from host vehicle  12  within a rear detection zone, as described in detail below. Again, several radars or lidars may be used to determine the distance to an object using well-known triangulation techniques.  
         [0023]     Controller  14  is communicatively connected to a countermeasure activation system  40 . Countermeasure activation system  40  is capable of activating one or more countermeasure attributes such as braking  42 , accelerating  44  or steering  46  systems for mitigating the effects of likely frontal, rear or dual crash situations. Controller  14  determines at least one countermeasure attribute associated with the braking  42 , accelerating  44  or steering  46  systems in response to signals received from frontal and rear object sensors,  20  and  30 , respectively.  
         [0024]      FIG. 2  displays a dual pre-crash situation response according to the present invention. Host vehicle  12  is positioned between vehicles  202  and  204  in a typical traffic situation. Frontal object sensor  20  generates an object signal when the presence of an object within a frontal detection zone  201  in front of host vehicle  1   2  is detected.  
         [0025]     Likewise, rear object sensor  30  generates an object signal when the presence of an object within a rear detection zone  203  in rear of host vehicle  1   2  is detected. Controller  14  is configured to determine the likelihood and severity of frontal and rear collisions. For the purposes of this embodiment, only frontal and rear collisions will be discussed, however, one skilled in the art will note that the present invention may be modified for mitigating various other angular collisions, including side collisions, as well.  
         [0026]     Frontal object sensor  20  enables controller  14  to determine the likelihood and severity of a primary frontal impact. In the event that a frontal impact is deemed likely, rear object sensor  30  enables controller  14  to determine the likelihood of a secondary rear impact. Controller  14  may then determine a countermeasure attribute for reducing the combined magnitude of the primary frontal and secondary rear impacts.  
         [0027]     Rear object sensor  30  enables controller  14  to determine the likelihood and severity of a primary rear impact. In event that a rear impact is deemed likely, frontal object sensor  20  enables controller  14  to determine the likelihood of a secondary frontal impact. Controller  14  may then determine a countermeasure attribute for reducing the combined magnitude of the primary rear and secondary frontal impacts.  
         [0028]     Depending on the likelihood and severity of the pending frontal and/or rear impacts determined by the frontal  20  and rear  30  object sensors, controller  14  is responsive to mitigate the effects of a frontal impact, a rear impact or a combination of frontal and rear impacts. Controller  14  determines at least one countermeasure attribute for mitigating the combined magnitude of frontal and rear impacts which may include the deployment of an accelerating, steering or braking system. A countermeasure attribute may also include the deployment of an airbag restraint system, a barrier device, various other collision mitigation devices or a combination thereof.  
         [0029]      FIGS. 3 and 4  describe the controller logic for frontal and rear primary collisions, respectively. The scenarios presented in  FIGS. 3 and 4  can occur interchangeably wherein a likely frontal collision can be detected before a likely rear collision or vice versa depending on the sensed conditions. Therefore, in certain instances the steps of  FIG. 3  may not necessarily precede the steps of  FIG. 4 .  
         [0030]     As such,  FIG. 3  displays a flowchart representation of pre-crash logic when a frontal sensor is sensing the likelihood of a frontal collision  300  according to the preferred embodiments of the present invention wherein a braking system  42  is used as a countermeasure attribute. In a first scenario, a likely frontal impact is detected with no likely rear impact. After starting, controller  14  at step  302  determines if the likelihood of the detected likely frontal impact, FL, and the likely severity of the detected frontal impact, FS, are greater than or equal to predefined threshold parameters, FL 1  and. FS 1 , respectively. Next, at step  304 , controller  14  determines an appropriate brake level for reducing the detected likely frontal impact. At step  306 , controller  14  determines if the likelihood of a secondary rear impact, RL, and the severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. If RL and RS are not greater than RL 1  and RS 1 , then controller  14  will determine a countermeasure attribute for activating braking system  42  to an appropriate brake level to reduce only the magnitude of the pending FL 1  and FS 1  frontal impact in step  314 .  
         [0031]     In a second scenario, a primary frontal impact of likelihood and severity, FL 1  and FS 1 , is detected with a secondary rear impact of likelihood and severity, RL 1  and RS 1 , wherein FL 1 , FS 1 , RL 1  and RS 1  are predetermined threshold parameters. After starting, controller  14  at step  302  determines if the likelihood of a primary frontal impact, FL, and the likely severity of such an impact, FS, are greater than or equal to predefined threshold parameters, FL 1  and FS 1 , respectively. Next, at step  304 , controller  1   4  determines an appropriate brake level to reduce the detected likely frontal impact. At step  306 , controller  14  determines whether the likelihood of a secondary rear impact, RL, and the likely severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. If RL and RS are greater than or equal to RL 1  and RS 1 , then controller  14  determines an appropriate brake level to reduce the pending frontal and rear impacts at step  308 . Continuing at step  310 , controller  14  determines if the likelihood of the secondary rear impact, RL, and the likely severity of such an impact, RS, are greater than or equal to RL 2  and RS 2 , wherein RL 2  and RS 2  are predetermined threshold parameters of greater magnitude than the RL 1  and RS 1  threshold parameters described above. If RL and RS are not greater RL 2  and RS 2 , then controller  14  will determine a countermeasure attribute for activating braking system  42  to reduce the combined magnitude of the pending frontal impact and pending RL 1  and RS 1  magnitude rear impact in step  314 .  
         [0032]     In a third scenario, a primary frontal impact of likelihood and severity, FL 1  and FS 1 , is detected with a secondary rear impact of likelihood and severity, RL 2  and RS 2 , wherein RL 2  and RS 2  are predetermined threshold parameters of greater magnitude than the RL 1  and RS 1  threshold parameters described above. After starting, controller  14  at step  302  determines if the likelihood of a primary frontal impact, FL, and the likely severity of such an impact, RS, is greater than or equal to predefined threshold parameters, FL 1  and FS 1 , respectively. Next, at step  304 , controller  14  determines an appropriate brake level to reduce the pending frontal impact. At step  306 , controller  14  determines whether the likelihood of a secondary rear impact, RL, and the likely severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. If so, then controller  14  will determine an appropriate brake level in step  308 . Continuing at step  310 , if controller  14  determines that RL and RS are greater than or equal to predefined threshold parameters RL 2  and RS 2 , then controller  14  will determine an appropriate brake level to reduce an RL 2  and RS 2  magnitude rear impact at step  312 . Controller  14  will determine a countermeasure attribute for activating braking system  42  to reduce the combined magnitude of the pending frontal impact and pending RL 2  and RS 2  magnitude rear impact in step  314 . If controller  14  determines that RL and RS are not greater than RL 2  and RS 2 , then controller  14  will determine a countermeasure attribute for activating braking system  42  to reduce the combined magnitude of the pending frontal impact and the pending RL 1  and RS 1  magnitude rear impact in step  314 , as described above.  
         [0033]      FIG. 4  displays a flowchart representation of pre-crash logic for a primary rear collision  400  according to embodiments of the invention of  FIG. 1 . In a first scenario, a primary rear impact is detected with no secondary frontal impact. After starting, controller  14  at step  402  determines if the likelihood of a primary rear impact, RL, and the severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. Next, at step  404 , controller  14  determines an appropriate throttle level and brake level to reduce the pending rear impact. At step  406 , controller  14  determines if the likelihood of a secondary frontal impact, FL, and the likely severity of such an impact, FS, are greater than or equal to predefined threshold parameters, FL 2  and FS 2 , respectively. If FL and FS are not greater than FL 2  and FS 2 , then controller  14  will determine a countermeasure attribute for activating braking system  42  and accelerating system  44  to reduce only the magnitude of the pending RL 1  and RS 1  magnitude rear impact in step  414 .  
         [0034]     In a second scenario, a primary rear impact of likelihood and severity, RL 1  and RS 1 , is detected with a secondary frontal impact of likelihood and severity, FL 2  and FS 2 , wherein FL 2 , FS 2 , RL 1  and RS 1  are predetermined threshold parameters. After starting, controller  14  at step  402  determines if the likelihood of a primary rear impact, RL, and the likely severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. Next, at step  404 , controller  14  determines an appropriate throttle level and brake level to reduce the pending RL 1  and RS 1  magnitude rear impact. At step  406 , controller  14  determines if FL and FS are greater than or equal to predefined threshold parameters, FL 2  and FS 2 , respectively. If FL and FS are greater than or equal to FL 2  and FS 2 , then controller  14  determines an appropriate throttle level and brake level to reduce the combined magnitude of the pending FL 2  and FS 2  magnitude frontal impact and pending rear impact at step  408 . Continuing at step  410 , controller  14  determines if FL and FS are greater than or equal to predetermined parameters FL 3  and FS 3 , which are greater in magnitude than FL 2  and FS 2 , respectively. If FL and FS are not greater than or equal to FL 3  and FS 3 , controller  14  will determine a countermeasure attribute for activating braking system  42  and accelerating system  44  to reduce the combined magnitude of the pending rear impact and the pending FL 2  and FS 2  magnitude frontal impact in step  414 .  
         [0035]     In a third scenario, a primary rear impact of likelihood and severity, RL 1  and RS 1 , is detected with a secondary frontal impact of likelihood and severity, FL 3  and FS 3 , wherein FL 3  and FS 3  are predetermined threshold parameters greater in magnitude than FL 2  and FS 2 . After starting, controller  14  at step  402  determines that the likelihood of a primary rear impact, RL, and the likely severity of such an impact, RS, are greater than or equal to predefined threshold parameters, RL 1  and RS 1 , respectively. Next, at step  404 , controller  14  determines an appropriate throttle level and brake level to reduce the pending RL 1  and RS 1  magnitude rear impact. At step  406 , controller  14  determines whether the likelihood of a secondary frontal impact, FL, and the likely severity of such an impact, FS, are greater than or equal to predefined threshold parameters, FL 2  and FS 2 , respectively. If FL and FS are greater than or equal to FL 2  and FS 2 , then controller  14  will determine an appropriate throttle level and brake level to reduce the combined magnitude of the pending frontal impact and pending rear impact at step  408 . Continuing at step  410 , if controller  14  determines that FL and FS are greater than or equal to predefined threshold parameters FL 3  and FS 3 , then controller  14  will determine an appropriate throttle level and brake level to reduce the combined magnitude of the pending rear impact and an FL 3  and FS 3  magnitude frontal impact at step  412 . Controller  14  will determine a countermeasure attribute for activating braking system  42  and accelerating system  44  to reduce the combined magnitude of the pending rear impact and FL 3  and FS 3  magnitude frontal impact in step  414 . If controller  14  determines that FL and FS are not greater than FL 3  and FS 3 , then controller  14  will determine a countermeasure attribute for activating braking system  42  and accelerating system  44  to reduce the combined magnitude of the pending rear impact and an FL 2  and FS 2  magnitude frontal impact in step  414 .  
         [0036]     The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternate embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its spirit and scope. Accordingly, the scope of the present invention is described by the appended claims and supported by the foregoing description.