Abstract:
Methods and apparatus are provided for protecting an unattended parked vehicle from being impacted by a moving vehicle under control of a driver. The apparatus comprises a detection and alarm system built into the unattended parked vehicle. When a moving vehicle comes within a predetermined distance from the unattended parked vehicle, the apparatus senses the presence of the moving vehicle and activates the alarm system. If the moving vehicle continues to approach the unattended parked vehicle, the activated alarm signals are increased in intensity. Typically, the alarm signals would be in the form of lights flashing and/or horn blowing, or any appropriate combination of audible and visual signals.

Description:
TECHNICAL FIELD  
       [0001]     The present invention generally relates to distance detectors on vehicles, and more particularly relates to ultrasonic distance detectors on unattended parked vehicles.  
       BACKGROUND  
       [0002]     Minor collisions between moving vehicles and unattended parked vehicles are common occurrences in areas such as parking lots. While the damage from this type of collision is not usually extensive, since the moving vehicle is usually maneuvering slowly into or out of a parking space, even a minor collision can prove to be an unpleasant and costly experience for the owner of the parked vehicle, as well as for the driver of the moving vehicle. Moreover, as the vehicle population increases, and as the variations in vehicle size and shape increase as well, the potential for collisions of this type is also likely to increase.  
         [0003]     Recent developments in automotive technology involve the use of ultrasonic distance detectors installed on a vehicle. Typically, the purpose of this type of distance detector is to warn the driver of an impending contact with another object. For example, ultrasonic sensors can be placed on the bumpers and sides of a vehicle to enable the determination of distances between the vehicle sensors and another object, such as a parked car or a tree. When a detector-equipped vehicle is within a predetermined distance from an object, an alarm can be activated to warn the driver of the situation. As such, the driver of an appropriately equipped vehicle can be alerted in time to avoid a collision with a nearby object.  
         [0004]     In general, however, such distance detection systems are only active when a vehicle is being driven, and are typically placed in an off state when the vehicle ignition is turned off, as in a parking situation. In addition, most automotive vehicles are not yet equipped with distance detection systems, so there is usually no type of active warning system in place for the kind of situation where an unequipped vehicle is maneuvering in the proximity of parked vehicles.  
         [0005]     Even if a parked vehicle is equipped with a distance detection system, the sensing process will be typically inactive, since the system is normally turned off when the vehicle is parked. Therefore, it is desirable to incorporate a type of detection system in a parked unattended vehicle that can be operative after the ignition is turned off, to warn an approaching driver of the possibility of an impending collision.  
         [0006]     Accordingly, it is desirable to provide a collision avoidance system for a vehicle that can be operative when the vehicle is in a parked (ignition off) state. In addition, it is desirable to implement this type of collision avoidance system with available technology and hardware, to minimize manufacturing production costs. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.  
       BRIEF SUMMARY  
       [0007]     According to various exemplary embodiments, devices and methods are provided for protecting an unattended parked vehicle from being impacted by a moving vehicle under the control of a driver. One device comprises a collision avoidance system installed within the unattended parked vehicle. The exemplary collision avoidance system typically includes distance sensing apparatus and a processor controlled alarm system. One or more distance boundaries are predetermined around the unattended parked vehicle, based on the type and configuration of the distance sensing apparatus. If a moving vehicle enters within a distance boundary, the alarm system can be activated. Typically, the alarm system provides increasingly intense visual and/or audible alarm signals as the moving vehicle crosses the predetermined distance boundaries while approaching the unattended parked vehicle.  
         [0008]     A first level warning signal may be in the form of turning on the lights of the unattended parked vehicle. A second level warning signal may be in the form of flashing the lights, or increasing their intensity. A third level warning signal may add a horn blowing in addition to the flashing lights, and so on.  
         [0009]     The exemplary collision avoidance system is typically configured with a processor and an ultrasonic distance sensing apparatus that can discriminate between a moving object and a stationary one, and can also determine which moving object is closest to the unattended parked vehicle. The exemplary collision avoidance system is typically powered by the main battery, or by an auxiliary battery, in the unattended parked vehicle. The exemplary collision avoidance system is typically placed in a standby mode initially, to conserve battery power, and then activated to full power when a moving vehicle is detected within a distance boundary. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and  
         [0011]      FIG. 1  is a block diagram of an exemplary vehicle collision avoidance system;  
         [0012]      FIG. 2  is an illustration of an exemplary boundary diagram for a vehicle collision avoidance system; and  
         [0013]      FIG. 3  is a flow diagram of an exemplary method for implementing a vehicle collision avoidance system.  
     
    
     DETAILED DESCRIPTION  
       [0014]     The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.  
         [0015]     Various embodiments of the present invention pertain to the area of collision avoidance systems embedded in unattended parked vehicles. An exemplary system of this type is typically configured to remain operative after the vehicle ignition system has been turned off. The exemplary collision avoidance system is generally configured to detect the presence of a moving vehicle within one or more predetermined distances from an unattended parked vehicle. The exemplary collision avoidance system can then activate one or more types of alarms to warn the approaching vehicle of an impending collision.  
         [0016]     According to an exemplary embodiment of a collision avoidance system  100  for an unattended parked vehicle  102 , as shown in block diagram form in  FIG. 1 , a number of distance sensors  104  are typically positioned at strategic locations around the perimeter of vehicle  102 . Each sensor  104  is suitably coupled to a controller  106 , which receives power from a power source  108  when vehicle  102  is parked with the ignition system turned off. Power source  108  is typically the main vehicle battery, but may also be any appropriate type of auxiliary power source. Various alarm actuators  110 ,  112 ,  114  are suitably coupled to controller  106 , and are used to activate warning indicators, such as tail lights  116 , headlights  118 , and horn  120 , respectively, or any appropriate combination of visual and/or audible signals.  
         [0017]     Sensors  104  may be any type of distance detection sensor that is appropriate for use on an automotive vehicle. One type of appropriate distance detection sensor is configured as an ultrasonic device. In order for an ultrasonic device to function as a distance detector, it is generally coupled to an ultrasonic transmitter/receiver (T/R) device  122 , which is shown in this embodiment as being incorporated into controller  106 , although other embodiments may also be used. T/R device  122  is typically configured to transmit ultrasonic pulses via sensors  104 , and to receive any return pulses from sensors  104  that may be reflected from an external object, such as a moving vehicle. A processor  124  is also typically incorporated into controller  106 , in conjunction with a memory  126 . Processor  124  is typically configured to calculate the distance from any sensor  104  to an external object, and to determine whether or not the external object is changing position, based on the elapsed time between transmission and reflected reception of ultrasonic pulses from a sensor  104 .  
         [0018]     As will be described in greater detail below, the exemplary method and device recognizes when a moving object is within a predetermined distance boundary with respect to vehicle  102 . When this occurs, processor  124  is typically enabled to activate one or more of alarm actuators  110 ,  112 ,  114 , in order to warn an approaching driver of a possible collision with vehicle  102 .  
         [0019]     According to the exemplary embodiment, as depicted in  FIG. 2 , vehicle  102  is shown in a parked position, at a distance D from a moving object, such as a vehicle,  202 . Concentric boundary lines  204 ,  206 ,  208  represent typical predetermined warning distance radii D 1 , D 2 , D 3 , respectively, from vehicle  102 . For example, D 1  might be approximately 3 feet, D 2  might be approximately 2 feet, and D 3  might be approximately 1 foot. The exemplary collision avoidance system  100  is typically configured so that if object  202  moves within the first boundary  204 , a first level of warning is typically activated. If object  202  moves within the second boundary  206 , a second level of warning is typically activated, and if object  202  moves within the third boundary  208 , a third level of warning is typically activated.  
         [0020]     Exemplary collision avoidance system  100  is typically configured to distinguish between a stationary object, such as a parking meter or a parked vehicle, and a moving object, such as vehicle  202 , that is within a distance boundary. In addition, collision avoidance system  100  is typically configured to limit the time duration of a warning alarm signal, to avoid becoming a public nuisance, and also to conserve battery power. Moreover, system  100  can generally discriminate between multiple sensor  104  input signals to determine which sensor  104  signal represents the closest distance between vehicle  202  and vehicle  102 . Optionally, system  100  may be activated or turned off by a remote signal from outside vehicle  102 , as well as from a manual or automatic control within vehicle  102 .  
         [0021]     As previously noted, any appropriate type of visual and/or audible warning alarms may be activated by processor  124  via alarm actuators  110 ,  112 ,  114  when a moving object, such as vehicle  202 , appears within a predetermined distance boundary ( 204 ,  206 ,  208 ). For example, a first level warning might typically be in the form of turning on tail lights  116  and/or headlights  118  when vehicle  202  moves within distance boundary  204 . A second level warning might typically take the form of intermittently flashing lights  116  and/or  118  when vehicle  202  moves within distance boundary  206 . Similarly, a third level warning might typically activate horn  120  in addition to flashing lights  116  and/or  118  when vehicle  202  moves within distance boundary  208 . Alternate embodiments of increasing levels of warning signals might include an increase in light intensity as a moving vehicle crosses successively closer distance boundaries, or an increase in the light flashing rate, or blowing the horn intermittently, for example.  
         [0022]     A typical operational sequence of exemplary collision avoidance system  100  can be represented by a system flow diagram  300 , as depicted in  FIG. 3 . A first step  302  is generally the initialization of collision avoidance system  100 , including the various parameters and algorithms stored in memory  126  of processor  124 . For example, predetermined warning distance radii D 1 , D 2 , D 3  are typically stored in memory  126 , along with their corresponding alarm levels and/or alarm combinations. In addition, distance boundaries  204 ,  206 ,  208  are typically established in accordance with the particular configuration and operating characteristics of sensors  104  and T/R  122 . Other typical initialization parameters and algorithms may include a time duration for the warning alarms, a time increment value, a sensor scan routine, and both standby and wake up modes for processor  124 , among others.  
         [0023]     In step  304 , a determination is made as to whether vehicle  102  is parked, and, typically, if the ignition is turned off. If that is not the case (No in step  304 ), the timekeeping function within processor  124  is reset (step  306 ) and the cycle is started again. If the vehicle is parked (Yes in step  304 ), collision avoidance system  100  is generally configured to be operative in a standby mode (step  308 ). In the exemplary embodiment, the standby mode may be activated automatically, or manually, or remotely. In the standby mode, exemplary system  100  is generally configured to operate at a reduced power level to conserve power source  108 . This type of power reduction can be achieved, for example, by generating the ultrasonic pulses to sensors  104  at a relatively slow rate, e.g., at approximately one pulse every 2 seconds.  
         [0024]     In step  310 , processor  124  monitors the signals fed back by sensors  104 , to determine which return signal, if any, represents the shortest distance between vehicle  202  and vehicle  102 . In step  312 , processor  124  determines whether or not the closest received signal is within the first boundary ( 204 ). If not (No in step  312 ), the timekeeping function within processor  124  is reset (step  306 ) and the cycle is started again. If vehicle  202  is within boundary  204  (Yes in step  312 ), processor  124  places system  100  in a wake up, or fully active, mode (step  314 ). In wake up mode, processor  124  typically activates a relatively high ultrasonic pulse rate, e.g., at approximately one pulse every second, in order to closely monitor the position of vehicle  202 .  
         [0025]     Step  316  represents a time out function of system  100 . That is, a timekeeping function within processor  124  keeps track of how long vehicle  202  is within a distance boundary, but not changing position. Processor  124  may also be pre-programmed to ignore a certain degree of distance variation as part of the position change determination. For example, wind conditions might cause part of a stationary object (vehicle, parking meter, etc.) to move a small distance, such as a fraction of an inch. If the pre-programmed distance variation threshold is set at one inch, for example, processor  124  will consider any movement less than one inch to be effectively zero (no change in position).  
         [0026]     If processor  124  determines that vehicle  202  has not changed position for a time duration that exceeds a predetermined time out limit, e.g., in an exemplary range of 30 to 60 seconds (Yes in step  316 ), the detection cycle is started again. If the time out limit is not exceeded (No in step  316 ), the timekeeping function is incremented, e.g., by 10 milliseconds (step  318 ), and a first alarm level is typically activated (step  320 ). As described previously, the first alarm level may take the form of activating tail lights  116  and/or headlights  118 , or might be any other type of visual or audible action deemed appropriate.  
         [0027]     In step  322 , a determination is made as to whether or not vehicle  202  has approached vehicle  102  at a distance less than D 2  (second boundary  206 ). If not (No in step  322 ), the detection cycle is started again. If vehicle  202  is detected within boundary  206 , a second alarm level is typically activated (step  324 ). The second alarm level is typically more intense than the first alarm level, and may take the form of flashing lights  116 ,  118  of vehicle  102  on and off, or increasing their intensity, or any other type of visual or audible action deemed appropriate.  
         [0028]     Step  326  follows the same pattern as step  322 , with respect to the third distance boundary  208 . That is, if vehicle  202  approaches vehicle  102  at a distance less than D 3 , a third alarm level is typically activated (step  328 ). The third alarm level is typically more intense than the second alarm level, and may take the form of blowing horn  120  of vehicle  102 , in addition to flashing lights  116 ,  118 . Horn  120  may be sounded intermittently, lights  116 ,  118  may be flashed more rapidly and/or may be increased in intensity, or any other type of visual and/or audible alarm may be activated, in order to provide an urgent warning to an approaching driver.  
         [0029]     After step  328 , the exemplary collision avoidance method continuously loops through the flow diagram steps described above until some action is taken to turn off the system. For example, system  100  might be inactivated by a remote signal, or by opening a door, or by starting up the ignition of vehicle  102 , as well as by other measures.  
         [0030]     Accordingly, the shortcomings of the prior art have been overcome by providing an improved collision avoidance system for an unattended parked vehicle. The unattended parked vehicle is typically provided with a distance sensing capability that surveys the area around the parked vehicle for approaching vehicles or other objects. If an approaching vehicle moves within a first predetermined distance from the parked vehicle, a first warning indicator is typically activated by the collision avoidance system within the parked vehicle to alert the driver of the approaching vehicle of an impending collision. If the approaching vehicle crosses successively closer predetermined distance boundaries with respect to the parked vehicle, the collision avoidance system within the parked vehicle typically generates increasingly intense types of warning signals. The exemplary collision avoidance system can typically be activated automatically, manually, or by remote control.  
         [0031]     While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the invention as set forth in the appended claims and the legal equivalents thereof.