Abstract:
The invention comprises a method of locating a vehicle, comprising: a) connecting a removable locator device to the vehicle, said locator device automatically noting when it has been connected to the vehicle and then using locating technology to retrieve, at regular intervals, location coordinates for the current location of said locator device, said location coordinates approximating the location of the vehicle; b) sensing a loss of connection between the locator device and the vehicle; c) automatically storing, as a waypoint on the locator device, the last location coordinates retrieved prior to sensing said loss of connection; and, d) removing the locator device from the vehicle to enable use of the locator device to return to the stored waypoint, wherein the stored waypoint represents the approximate location of the vehicle.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of locating and tracking devices. In particular, it relates to a system and method for locating a vehicle. 
     BACKGROUND OF THE INVENTION 
     One of the difficulties encountered when driving in a large or unfamiliar city is locating and returning to one&#39;s vehicle after parking. Particularly in the case of rental vehicles, where both the vehicle and city are unfamiliar to the driver, and with the large size of parking garages in malls, hotels and other venues, it can be very difficult for the driver to not only locate the parked vehicle, but also to determine how to return to the location. However, with the development and increased usage of portable navigation systems, such as GPS tracking and mapping devices, the potential exists to use those systems to assist the driver in locating their vehicle after leaving it parked. 
     For example, U.S. Pat. Nos. 6,392,592 and 6,694,258 to Johnson et al. (“Johnson”) disclose a hand-held car locator device consisting of two parts, a transmitter/receiver in the vehicle, and a fob which is carried by the user. When the user wants to locate the vehicle, they activate the fob, and a signal is sent to the vehicle, which then gets its current location using GPS or similar means, and sends the location back to the fob for the user to see. Johnson also discloses automatic transmission of location to the fob, such as upon locking of the vehicle doors. 
     Problems with the above-mentioned Johnson patents include the following: it requires that a GPS or similar location tracking unit be located in the vehicle at all times and it requires that the location tracking unit be powered by the vehicle&#39;s battery while the vehicle is off, which can present vehicle battery drainage issues. Johnson also requires a fob with (1) transceiver technology, (2) the ability to interpret a signal from a location tracking unit, (3) the ability to display location and/or directional information, and (4) strong transmission signal capabilities—which necessitates a significant power source—in order to effectively contact the tracking unit in the vehicle (as the signal may be issued from a great distance and can be blocked by concrete walls or other such obstructions). 
     Another example, U.S. Pat. No. 6,407,698 to Ayed (“Ayed”) discloses a method of locating a parked vehicle using a sensor incorporated into the vehicle and a mobile GPS device where the sensor is activated when the vehicle is parked and sends a signal to the GPS device. The GPS device then retrieves the current coordinates on receiving the signal from the sensor. The Ayed method requires modification of the vehicle to incorporate the sensor, as well as possession of a separate mobile GPS device by the user. In Ayed, as the location coordinates are retrieved by the GPS device once the vehicle is parked, there is also the risk of a failure to connect to the GPS satellites in a timely manner, such that the retrieved coordinates do not correspond to the vehicle&#39;s parking location. 
     As with Johnson, Ayed requires a second device to communicate with the GPS device to determine the location of the parked vehicle. Another problem is the need to modify the vehicle to include sensors to indicate to the locator device that the vehicle is parked, or other devices, such as a cradle, to accommodate the locator device. 
     Additionally, Ayed requires that the sensors installed in the vehicle have sufficient sophistication and complexity to both accurately and consistently note that the vehicle is parked and to then communicate with the GPS device, creating a risk of failure in that the parking of the vehicle may not be detected by the sensor and, as a result, a failure to communicate the signal to the GPS device. 
     Yet another example is found in U.S. Pat. No. 6,489,921 issued to Wilkinson (“Wilkinson”). The Wilkinson patent discloses a handheld device (i.e. a keychain fob) which senses when it has been moved out of range of an RF signal tag that is mounted on the vehicle&#39;s dashboard near the vehicle&#39;s ignition. When the user removes the key (and keychain fob apparatus) from the immediate range of the vehicle&#39;s ignition, which is likely indicative of the user being in the process of leaving the vehicle, the RF signal is therefore lost. This signal loss automatically prompts the device to initiate the device&#39;s GPS receiver to seek satellite signals and, upon securing said signals, to record the device&#39;s coordinates. These coordinates, in turn, are meant to correspond to the location of the user&#39;s parked vehicle. When re-activated, the device gets the GPS coordinates for its current location, and calculates the shortest distance to the recorded coordinates. It then displays on-screen an arrow indicating the direction the user should travel to get back to the original coordinates. Once the device is back within range of the RF signal, it disengages and waits for the RF signal to drop below threshold again to resume the process. 
     Problems with Wilkinson include an issue with apparatus size, as Wilkinson expresses a need for an apparatus with locating technology capabilities that is small enough in size and weight to be placed on a key chain (and thus to be in range of the RF tag that is to be placed by the vehicle&#39;s ignition). 
     Wilkinson and Ayed share a common limitation, in that the coordinates of the vehicle are retrieved after the vehicle is parked. Initiating the locating technology after parking creates a significant risk that the coordinates will not be retrieved in a timely fashion, as the device needs time to secure multiple satellite signals in order to determine its location. By the time the device secures the required satellite signals and calculates its location the user may have walked a significant distance from their vehicle, thus significantly limiting the device&#39;s ability to secure an accurate determination of the location of the vehicle. This, in turn, largely undermines the purpose and intent of both of these patents. 
     U.S. Pat. No. 6,363,324 to Hildebrant, which has two GPS receivers, one in car and another in the handheld device, and discloses a display using a direction arrow and an elevation marker to indicate the direction to a parked vehicle. The Hildebrant receivers retrieve and store the location coordinates once the vehicle is parked. Hildebrant is limited in that two GPS devices are required. 
     U.S. Pat. No. 6,791,477 and No. 7,068,163, both issued to Sari et al. (“Sari”). The Sari patents disclose a locator device (key “faub” (sic) or wireless telephone) that retrieves a waypoint from a second device in response to a triggering event such as the parking of a vehicle. The waypoint is determined by the second device using coordinates retrieved prior to the triggering event. Sari is limited in that two GPS devices are required, and that the waypoint is transmitted between devices, creating a risk of a corrupted or missed waypoint. 
     There is a need for a method of locating a vehicle that uses a single GPS device, ideally in a one-step operation that does not require any modification of the vehicle. 
     There is also a need for a method of locating a vehicle that functions autonomously, enabling the recording of the vehicle&#39;s location on a GPS-enabled device without any user intervention and without the requirement for noteworthy modifications to the vehicle. Ideally, such a method would use a device that is unobtrusive and requires minimal or no modification to the vehicle. 
     There is further a need for a method of locating a vehicle that does not rely on retrieving coordinates after the vehicle is parked, to increase the likelihood of the coordinates being captured and stored in a timely fashion so that the co-ordinates are in very close proximity to the vehicle&#39;s actual location. 
     It is an object of this invention to partially or completely fulfill one or more of the above-mentioned needs. 
     SUMMARY OF THE INVENTION 
     The invention comprises, in one embodiment, a method of locating a vehicle, comprising: a) connecting a removable locator device to the vehicle, said locator device automatically noting when it has been connected to the vehicle and then using locating technology to retrieve, at regular intervals, location coordinates for the current location of said locator device, said location coordinates approximating the location of the vehicle; b) sensing a loss of connection between the locator device and the vehicle which is indicative of the vehicle being parked; c) automatically storing, as a waypoint on the locator device, the last location coordinates retrieved prior to sensing said loss of connection; and, d) removing the locator device from the vehicle to enable use of the locator device to return to the stored waypoint, wherein the stored waypoint represents the approximate location of the vehicle. When the user wishes to return to their vehicle, they use the locator device to guide them back to the waypoint representing the approximate location of their vehicle. 
     The locator device is preferably an electronic device capable of determining or retrieving its location, preferably a device that uses GPS technology, such as a commercial GPS receiver, a cell phone or PDA with a built-in GPS receiver, a cell phone or PDA that is GPS-capable (e.g. has a GPS chipset) or a similar device. Alternatively, the locator device may be a cell phone or PDA that uses an alternate method of locating cell phones such as, but not limited to, cell phone triangulation. 
     In an alternative embodiment, the locator device emits a signal to confirm the successful recording of the waypoint and to remind users to take the locator device with them when they exit their vehicles. 
     The invention further comprises a system for locating a parked vehicle, comprising a locator device, the locator device being removably coupled to the vehicle and capable of using locating technology to retrieve, at regular intervals, location coordinates for the current location of said locator device, said location coordinates approximating the location of the vehicle, and the locator device including the ability to detect a loss of connection to the vehicle, storing the last retrieve location coordinates as a waypoint approximating the location of the vehicle, and guiding the user back to the waypoint representing the approximate location of their vehicle. 
     The invention further comprises, in another embodiment, a method of locating a vehicle, comprising: a) locating a beacon device in the vehicle, the beacon device being capable of wireless signal communication according to preset parameters; b) detecting, on a locator device, the presence of the beacon device in the vehicle via the wireless signal; c) automatically initiating and using locating technology to establish current location coordinates for the locator device upon detecting the beacon device; d) using location technology to update the current location coordinates of the locator device at regular intervals for as long as the locator device remains within signal range of the beacon device, the signal range being such that a person would still be within close range of their vehicle (e.g. 10 meters or less) when the locator device was moved out of range of the signal; automatically storing, as a waypoint on the locator device, the last updated location coordinates upon the locator device ceasing to detect the presence of the beacon device, wherein the stored waypoint represents the approximate location of the vehicle. When the user wishes to return to their vehicle, they use the locator device to guide them back to the waypoint representing the approximate location of their vehicle. 
     The beacon device may communicate with the locator device continuously, or may communicate with the locator device on a periodic basis. The time interval between communications should not exceed the approximate time that it would take a person to walk a distance from his vehicle to a location at which he or she would no longer be fairly easily able to determine the location of his or her vehicle (i.e. 60 seconds). The shorter the signal interval, the more accurately the location of the vehicle will be noted in the locator device and the less effect a signal failure would have on the determination of the vehicle location. 
     The beacon device and locator device will use a communications technology such as, but not limited to, Bluetooth or RFID as a means to recognize and communicate with one another. The locator device is an electronic device, capable of determining or retrieving its location, preferably a device that uses GPS technology, such as a commercial GPS receiver, a cell phone or PDA with a built-in GPS receiver, a cell phone of PDA that is GPS-capable (e.g. has a GPS chipset) or a similar device. Alternatively, the locator device may be a cell phone or PDA that uses a means for locating cell phones such as, but not limited to, cell phone triangulation or WiMAX. 
     The invention further comprises a system for locating a parked vehicle, comprising: a) a beacon device that is located in the vehicle, the beacon device being capable of wireless signal broadcasting according to preset parameters b) a locator device operative to detect the wireless signal of the beacon device, and to automatically initiate and use location technology to update its current location for as long as the locator device remains within signal range of the beacon device and to record the last location as a waypoint upon ceasing to detect the wireless signal, wherein the locator device denotes the waypoint as the approximate location of the parked vehicle, and guiding the user back to the waypoint representing the approximate location of their vehicle. 
     Other and further advantages and features of the invention will be apparent to those skilled in the art from the following detailed description thereof, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described in more detail, by way of exemplary embodiments. The exemplary embodiments described herein constitute only possible implementations of the described invention and it is recognized that one skilled in the art may be able to devise alternate equivalent embodiments of the invention. The exemplary embodiments are herein below described with reference to the accompanying drawings, in which like numbers refer to like elements, wherein: 
         FIG. 1  is an exemplary embodiment of the present invention; 
         FIG. 2  is a flowchart showing the process for establishing a waypoint approximating a vehicle&#39;s location according to the present invention; 
         FIG. 3  is a flowchart showing the process for guiding a user to the waypoint established by the process of  FIG. 2 ; 
         FIG. 4  is a screen capture off a locator device when the system is on but not in active use; 
         FIG. 5  is a screen capture off a locator device during the location monitoring step; 
         FIG. 6  is a screen capture off a locator device when the trigger event has occurred and the parked vehicle&#39;s approximate location has been captured; 
         FIGS. 7 and 7   a  are screen captures off locator devices which relate to when the user prompts the locator device to guide the user back to the approximate location of their parked vehicle; 
         FIG. 8  is a screen capture off a locator device during the return to waypoint phase when the distance between the user&#39;s current location and the approximate location of the parked vehicle is significant enough such that the locator device cannot readily be displayed on a map at the same time; 
         FIG. 9  is a screen capture off a locator device during the return to waypoint phase when the distance between the user is close enough to the approximate location of the parked vehicle such that the locator device can display both of these points on a map at the same time; 
         FIG. 10  is a screen capture off a locator device for the alternative embodiment which depicts the locator device prompting the user to report as to whether they can see their vehicle; 
         FIG. 11  is a screen capture off a locator device that depicts the locator device resetting after a trigger event; 
         FIG. 12  is a flowchart showing the process for establishing a waypoint approximating a vehicle&#39;s location according to an embodiment of the present invention; and 
         FIG. 13  is a flowchart showing the process for establishing a waypoint approximating a vehicle&#39;s location according to an alternative embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present inventive system and method comprises a locator device  20 , as shown in  FIG. 1 , which is capable of determining its location (via GPS or other location determining systems), recording a waypoint of its present, and providing directions to a recorded waypoint from its current location. The locator device  20  is operative in the present invention to automatically set a waypoint approximating the location of a parked vehicle and to enable a user to return to that waypoint, and thus the vehicle, at a later time. 
     The locator device  20  is preferably an electronic device capable of determining or retrieving its location, preferably a device that uses GPS technology, such as a commercial GPS receiver, a cell phone or PDA with a built-in GPS receiver, a cell phone or PDA that is GPS-capable (e.g. has a GPS chipset) or a similar device. Alternatively, the locator device may be a cell phone or PDA that uses an alternate method of locating cell phones such as, but not limited to, cell phone triangulation. 
     As shown in  FIG. 2 , the locator device  20  is initially activated (step  110 ) prior to user entering vehicle or while user is in the vehicle. Once activated, the locator device  20  automatically launches the system (step  112 ), and then regularly determines its present location coordinates (step  114 ) using GPS or an equivalent location coordinate system. The locator device  20  then monitors (step  116 ) for a triggering event. If this triggering event is not detected, the process continues (step  118 ). Once the triggering event is detected, the locator device  20  records a waypoint (step  120 ) corresponding to the last set of location coordinates. This waypoint then acts as a proxy for the vehicle&#39;s location. 
     To return to the waypoint, and thus the vehicle, the user follows the steps as shown in  FIG. 3 . First, the user activates the locator device  20  (step  210 ) with instructions to return to the established waypoint. The locator device  20  then acquires its current location using GPS or other locating technology (step  212 ). The locator device  20  displays the user&#39;s current location on a graphical map, with the user&#39;s current location indicated by a symbol such as a triangle that depicts the direction that the user is walking. The locator device  20  determines if the distance from the user&#39;s current location and the vehicle&#39;s approximate location is such that these two waypoints can be displayed on a graphical map on the locator device  20  display at the same time (step  214 ). If both the user&#39;s current location and the location of the vehicle can not be displayed on the map at the same time (e.g. the two points are more than 100 meters apart, depending on the scale of the map), then the locator device  20  display shows, and also displays an arrow depicting the general direction toward the approximate location of the vehicle (step  216 ). When the distance to the waypoint is sufficiently reduced such that both the user&#39;s location and the waypoint fit on the map scale, the general direction arrow toward the approximate location of the vehicle no longer appears and the waypoint is shown (step  218 ) by a suitable symbol, such as a car. A second triggering event occurs when the user has returned to the approximate location of their vehicle (step  220 ), at which point the locator device  20  resets (step  222 ). 
     Additionally, or alternatively, the locator device  20  can display a highlighted route on the map from the user&#39;s current location to the waypoint representing the approximate location of the parked vehicle. As described, the preferred output device for the locator device  20  is a visual graphic display, however, a text display and/or speakers can also be used as output devices. In combination with, or as an alternative to the map, the user can be provided with a set of text instructions and/or spoken instructions to guide them from their current location to the waypoint. The instructions can be provided as a list (preferred for text instructions), or as needed as the user progresses towards the waypoint (preferred for spoken instructions). 
     A series of screen captures from a cellular phone implementation of the present inventions are shown as  FIGS. 4-11 . In  FIG. 4 , the locator device  20  is idle, and the location of the vehicle is unknown, as marked by a symbol of a car with a question mark  400 . In  FIG. 5 , the trigger event has occurred, GPS or other locating technology has been initiated, and the locator device  20  proceeds to update and maintain the vehicle&#39;s location co-ordinates  500 . 
     In  FIG. 6  the trigger event denoting that the user has removed the locator device  20  from the vehicle has occurred, at which point the locator device  20  notes the last known waypoint as the approximate location of the vehicle. The parked vehicle&#39;s approximate location is denoted via a symbol (such as a car)  600  on a map of the area around the approximate location of the parked vehicle  610 . 
     In  FIGS. 7 and 7   a , the user has activated the locator device  20  and has prompted  700  the locator device  20  to indicate a route to the waypoint representing the approximate location of the parked vehicle. In  FIG. 8 , the user&#39;s location and heading are marked by a triangle  800 . As the approximate location of the parked vehicle is a significant distance  810  from the user  800  and is thus located outside the boundaries of the map, a directional graphic  820  is shown indicating the general direction toward the waypoint from the user&#39;s position  800 . 
     As depicted in  FIG. 9 , when the user  900  and the approximate location of the vehicle  910  are close enough  920  to be on the same map (approximately 100 meters), the directional graphic ( FIG. 8 ,  820 ) no longer appears on the map. 
     In  FIG. 11 , when a second trigger event occurs to denote that the user has returned to the approximate location of their vehicle, the locator device  20  resets  1100 . 
     Example 1 
     In one embodiment of the present invention a locator device  20 , such as a portable GPS mapping device, is placed within a vehicle and coupled to the vehicle&#39;s power supply. The locator device is designed such that it can be easily removed from the vehicle by the user and later used to guide the user back to the stored waypoint representing the approximate location of the vehicle. The process for using the locator device is shown via flowchart in  FIG. 12 . 
     Operationally, if the locator device  20  is not already on, then the user turns it on (step  1210 ). The user connects the locator device  20  to the vehicle using the locator device&#39;s existing external power input port (step  1212 ). The order of steps  1210  and  1212  is interchangeable, depending on the nature of the device and the user&#39;s preferences. The locator device  20  automatically senses the connection of an external power source. The locator device  20  then monitors its current location on a regular basis (step  1214 ) using GPS signals or similar location systems. The locator device  20  also monitors (step  1216 ) for the cessation of the connection to the external power source. As long as the power source remains connected (step  1218 ), the locator device  20  continues to determine its current location. 
     The cessation of the external power source is readily sensed by units such as portable GPS units and cell phones as these devices can automatically determine that they are no longer being powered by an external source (in this case being the vehicle). This loss of an external power source serves as the triggering event for the locator device as described in  FIG. 2 . Thus, when the external power source connection is terminated, the locator device stores the last recorded GPS coordinates as a waypoint (step  1220 ), serving as a proxy for the location of the parked vehicle. The driver then removes the locator device  20  (step  1222 ) when exiting the vehicle and is able to later use the stored waypoint on the locator device  20  to return to the parked vehicle as described in  FIG. 3 , with the connecting of the locator device  20  to the vehicle&#39;s power supply serving as the trigger event to reset the locator device  20 . 
     As an additional feature, the locator device  20  can emit an audible tone and/or provide a text message to confirm that the waypoint was recorded. An audible tone can also provide a reminder for the user to take the locator device from the vehicle. 
     In some vehicles, the vehicle ceases to provide power to its external power ports when the vehicle is turned off. In these instances, the locating device  20  will lose external power from the vehicle when the vehicle is turned off. This loss of external power serves as the triggering event. However, some vehicles continue to supply power to external devices even when the user has removed the key from the ignition. In that case, the locator device  20  must be physically disconnected to register the cessation of an external power supply and the disconnection will act as the triggering event. 
     Alternatively, the location can be stored in response to a triggering event from the user or user&#39;s vehicle, such as manual activation by the user on the locator device  20 , by a voice command from the user, the engine being shut off, the door locks being disengaged, or the transmission being set to “Park”, the last three representing the type of event that results in the vehicle terminating the external power source. 
     By storing the location on the locator device  20 , the need for the user to carry a second device, such as a key fob, is eliminated. Additionally, there is no need to modify the vehicle to provide a signal to the locator device  20 , although minor modifications to produce the triggering event may be desirable for the purpose of the alternative embodiments detailed above. Lastly, as there is no communication with a second device required, there is no transmission of information that can be degraded, corrupted, or possibly stolen. 
     Another advantage gained is that the removable locator device  20  is expected to have a larger display and greater functionality than a key fob or similar device, making it easier for the driver to view the navigational instructions to return to the vehicle and taking into account the current challenges of incorporating global positioning system technology into a device small enough to be placed on a key chain. The larger size also enables additional features, such as a combined text and map display, which would likely not be clearly visible on a smaller device. 
     A further advantage gained is that, unlike prior art devices, such as those disclosed by Wilkinson and Ayed, by initiating the global positioning or other locating system when the user first connects the locator device  20  to the vehicle&#39;s power source, the locator device  20  can reasonably be expected to have sufficient time to interact with the global positioning or other locating system prior to the user parking their vehicle and thus be able to secure a waypoint that, with reasonable accuracy, represents the current location when the user parks their vehicle. 
     Example 2 
     Another embodiment of the inventive system and method presented herein comprises using a short-range beacon device  10  which is placed in the vehicle, and which incorporates short-range wireless communications technology, such as Class 2 Bluetooth communications functionality. This beacon device  10  is detectable by a locator device  20  when the locator device  20  is within signal range of the beacon device  10 . Using Bluetooth, for example, the beacon device&#39;s signal range would be approximately 10 meters, subject to the power and sensitivity of the transmitting and receiving devices, and reductions from interference and blockage. The locator device  20  is user-portable and preferably a cellular phone or GPS mapping device. The process for using the locator device  20  is shown via flowchart in  FIG. 13 . 
     In operation, as shown in  FIG. 13 , if the locator device  20  is not already on, then the user turns it on (step  1310 ), at which point the application automatically launches in the background. The locator device  20  continuously attempts to detect the signal from the beacon device  10  (step  1312 ), and then attempts to establish a Bluetooth piconet with the beacon device  10 , according to Bluetooth protocols for establishing connections between Bluetooth-enabled devices. If the beacon is not detected, the locator device will idle (step  1314 ) for a pre-set time period before attempting to detect the beacon device  10  again (step  1314 ). The beacon signal can be emitted continuously, or at regular intervals, preferably of less than 60 seconds. 
     Once the beacon device  10  is detected by the locator device  20 , the locator device  20  automatically initiates and uses its locating technology (e.g. GPS) to monitor its current location (step  1316 ). The locator device  20  then repeats the process of detecting the signal from the beacon device  10 . Once the beacon signal is detected, the locator device then (step  1318 ) returns to monitoring its current location and repeats the process. Thus, as long as the locator device  20  continues to detect the signal from the beacon device  10 , the locator device  20  regularly updates its current location as the approximate location of the vehicle. 
     When the locator device  20  no longer detects the beacon device  10 , most likely because the locator device  20  has been moved out of range of the beacon device  10  by the user after he or she parks and walks away from his or her vehicle, the locator device  20  automatically records the last monitored coordinates as a waypoint (step  1320 ) and enters an idle state (step  1322 ) until activated by the user. Thus, the locator device can then be used to return to recorded waypoint, which will approximate the location where the vehicle is parked. The driver is able to later use the stored waypoint on the locator device  20  to return to the parked vehicle as described in  FIG. 3 , with the user returning to the vehicle and bringing the locator device  20  back into range of the beacon device  10  serving as the trigger event to reset the locator device  20 . 
     As depicted in  FIG. 10 , when the user brings the locator device  20  back into range of the beacon device  10 , a text box appears on the locator device screen indicating text to the effect of “Do you see your car?” (step  1000 ). If the user selects “Yes”, then the locator device resets and returns to Maintaining Car Position mode (as described above in  FIG. 11 ). If the user selects “No”, then the locator device continues to display the user&#39;s current position and the car icon depicting the waypoint that approximates the location of the vehicle. If the user stays in range of the beacon device  10  for a period of time (e.g. an additional 15 seconds), the locator device  20  prompts them with the above question again. This cycle continues until the user selects “Yes” or until the locator device  20  notes that (1) it is in range of the beacon device  10  and (2) that the locator device  20  is moving at a rate consistent with a vehicle in motion. At this point the locator device  20  “assumes” that the user has entered the vehicle and has forgotten to press “Yes”, and reverts to Maintaining Car Position mode (as described in  FIG. 11 ). 
     As an additional feature, the locator device  20  can emit an audible tone and/or provide a text message to confirm that the waypoint was recorded. An audible tone can also provide a reminder for the user to take the locator device  20  from the vehicle. 
     The beacon device  10  is effectively a ‘dumb’ device, merely allowing the locator device to detect it according to preset parameters. By structuring the beacon device  10  in this fashion, several advantages are gained. First, the work required to detect loss of signal (i.e. that the car is parked and the user has left the vehicle) and record the waypoint is passed on to the locator device, thus likely making the beacon device less expensive to manufacture and less likely to malfunction. Second, by operating on the basis of the presence or absence of the beacon signal, the need to actually detect the car parking or a similar event is eliminated, reducing the probability of failure to record the waypoint at the appropriate time. 
     The beacon device  10  can be battery-powered, self-powered by other means (e.g. solar cells), adapted to plug into a power source (i.e. cigarette lighter or power socket) in the vehicle, or permanently affixed to and powered by the vehicle. 
     Bluetooth is preferred for the wireless communication between the beacon device  10  and the locator device  20 , as the signal range is low enough to provide activation near the vehicle&#39;s location, while also providing encryption such that a particular beacon can be associated with a particular locator device, thus preventing interference and false signals from other beacons during normal use. 
     As an alternative to initial beacon detection step  1312 , the locator device  20  can be user-activated, eliminating the need for the initial detection of the beacon. However, user activation creates the potential for the user to fail to activate the locator device  20 , which is avoided by automatic activation. 
     INDUSTRIAL APPLICABILITY 
     By storing the location on the locator device  20 , the need for the user to carry a second device for the sole purpose of locating their vehicle, such as a key fob, is eliminated. Additionally, there is no need to modify the vehicle to provide a signal to the locator device  20 , although minor modifications to produce the triggering event may be desirable for the purpose of the alternative embodiments detailed above. Lastly, as there is no communication with a second device required, there is no transmission of information that can be degraded, corrupted, or possibly stolen. 
     Another advantage gained is that the removable locator device  20  is expected to have a larger display and greater functionality than a key fob or similar device, making it easier for the driver to view the navigational instructions to return to the vehicle and taking into account the current challenges of incorporating global positioning system technology into a device small enough to be placed on a key chain. The larger size also enables additional features, such as a combined text and map display, which would likely not be clearly visible on a smaller device 
     A further advantage gained is that, unlike prior art devices, such as those disclosed by Wilkinson and Ayed, by initiating the global positioning system when the user first connects the locator device  20  to the vehicle&#39;s power source (or, in the alternate embodiment, when the locator device  20  first enters the range of the beacon device  10 ), the locator device  20  can reasonably be expected to have sufficient time to interact with the global positioning system prior to the user parking their vehicle and thus be able to secure a waypoint that, with reasonable accuracy, represents the current location when the user parks their vehicle. 
     There is the possibility that the user is able to find and return to their vehicle without the need to refer to the locator device  20  and to the stored waypoint therein. As the steps to record the waypoint are preferably fully automated “(noting connection to external power or noting that device has entered range of beacon, launching GPS, monitoring position, recording a waypoint), they will continue to take place (unless user has deactivated the locator device  20 ) and this process is unaffected by the user&#39;s decision. 
     However, if the user elects to not use the locator device  20  to help them return to their vehicle, then the method to return to the vehicle, which must be initiated by user, no longer takes place. However, the locator device  20  still needs to reset to start tracking location again when user gets back into their vehicle and moves on to their next destination. 
     Considering Example 1, when the user reconnects the locator device  20  to the vehicle&#39;s power supply then the locator device  20  automatically resets, regardless of whether the user activated the locator device  20  to return to the vehicle. As such, the user electing to not use the locator device does not have any implications in this context for the embodiment described in Example 1. 
     Considering Example 2, the locator device  20  notes when it is back in range of beacon device  10 . If locator device  20  stays in range of beacon device  10  for an extended period of time (e.g. in excess of 60 seconds) then the locator device assumes that the vehicle is back in motion and the locator device  20  automatically resets as previously described. 
     While the above examples have been presented in the context of locating parked passenger vehicles, particularly automobiles, the device method is equally applicable to other vehicles (e.g. transport trucks, boats, motorcycles, bicycles) that are parked by a driver at a location that must be returned to at a later time. 
     This concludes the description of presently preferred embodiments of the invention. The foregoing description has been presented for the purpose of illustration and is not intended to be exhaustive or to limit the invention to the precise form disclosed. It is intended the scope of the invention be limited not by this description but by the claims that follow.