Patent Publication Number: US-2010125415-A1

Title: Monitoring system for low-speed mobility vehicle and another type of vehicle

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a monitoring system for a low-speed mobility vehicle and another or different type of vehicle, particularly to a monitoring system for vehicles including a low-speed mobility vehicle, such as a power wheelchair, and a vehicle of a different type from the low-speed mobility vehicle, such as a four-wheeled vehicle (automobile). 
     2. Description of the Related Art 
     Various efforts have been made to improve the driving safety of four-wheeled vehicle and the like. For example, Japanese Laid-Open Patent Application No. 2008-27170 (&#39;170) teaches a vehicle monitoring system that is equipped with a remote monitoring device communicatably connected to a vehicle and a device provided at an intersection or the like for detecting pedestrians and is configured so that the remote monitoring device alerts the vehicle when a pedestrian is detected in the vicinity of the vehicle. 
     On the other hand, recent years have seen the spread of low-speed mobility vehicles such as power wheelchairs that travel at very low speeds comparable to human walking speed and are suitable for use by the elderly and others with walking difficulties. An example can be found in Japanese Laid-Open Patent Application No. 2007-112363 (&#39;363). 
     The operator (driver) of a low-speed mobility vehicle of this type must keep a close and constant lookout for approaching vehicles. The operator therefore experiences a considerable burden and much inconvenience particularly when driving in heavy-traffic environments such as a city. A conceivable way of making the vehicle monitoring system capable of reducing the burden on the operator would be to inform and alert both the low-speed mobility vehicle and the other vehicle when they approach one another. However, the references &#39;170 and &#39;363 are both totally silent on this point. 
     SUMMARY OF THE INVENTION 
     The object of this invention is therefore to overcome this drawback by providing a monitoring system for a low-speed mobility vehicle and a different type of vehicle, which comprises the low-speed mobility vehicle and a vehicle of a different type, reduces the driving burden on the operators and enhances driving safety. 
     In order to achieve the object, this invention provides a system for monitoring a low-speed mobility vehicle and a vehicle of different type from the low-speed mobility vehicle, and having a remote monitoring device adapted to be connected to the low-speed mobility vehicle and the vehicle of different type through a first communicator, wherein the improvement comprises: each of the low-speed mobility vehicle and the vehicle of different type includes: a first transmitter that transmits vehicle location data to the remote monitoring device through the first communicator; and the remote monitoring device includes: a first distance calculator that calculates an inter-vehicle distance between the low-speed mobility vehicle and the vehicle of different type based on the vehicle location data transmitted from the low-speed mobility vehicle and the vehicle of different type; and a second transmitter that transmits an approaching signal to the low-speed mobility vehicle and the vehicle of different type through the first communicator indicating that the vehicles are approaching each other when the inter-vehicle distance calculated by the first distance calculator is equal to or less than a first predetermined value. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects and advantages of the invention will be more apparent from the following description and drawings in which: 
         FIG. 1  is a block diagram showing the overall configuration of a monitoring system for a low-speed mobility vehicle and a different type of vehicle according to an embodiment of this invention; 
         FIG. 2  is a perspective view of the low-speed mobility vehicle shown in  FIG. 1  as seen at an angle from the front; 
         FIG. 3  is a perspective view of the low-speed mobility vehicle shown in  FIG. 1  as seen at an angle from the rear; 
         FIG. 4  is an enlarged plan view of an operating unit of the low-speed mobility vehicle shown in  FIG. 2 , etc.; 
         FIG. 5  is a flowchart showing the operation of a remote monitoring device shown in  FIG. 1 ; 
         FIG. 6  is a flowchart showing the operation of the low-speed mobility vehicle shown in  FIG. 1 ; and 
         FIG. 7  is a flowchart showing the operation of a vehicle shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  is a block diagram showing the overall configuration of a monitoring system for a low-speed mobility vehicle and a different type of vehicle in accordance with an embodiment of this invention. 
     In  FIG. 1 , the reference numeral  10  designates the monitoring system for a low-speed mobility vehicle and a different type of vehicle. The monitoring system  10  comprises a low-speed mobility vehicle  12 , a vehicle (e.g., four-wheeled vehicle)  14  of a different type from the low-speed mobility vehicle, and a remote monitoring device  16  communicatably connected to the low-speed mobility vehicle  12  and vehicle  14 . 
       FIG. 2  is a perspective view of the low-speed mobility vehicle  12  as seen at an angle from the front, and  FIG. 3  is a perspective view thereof as seen at an angle from the rear. 
     As shown in  FIGS. 2 and 3 , the low-speed mobility vehicle  12  comprises a vehicle body frame  20  supported by four wheels  18 , a seat  22  provided on the body frame  20  to be seated by an operator (rider/user) not shown in the drawings, and an operating unit  24  provided for manual operation by the operator. The low-speed mobility vehicle  12  is designed for use by, for example, an elderly person. It is a relatively small, single-passenger electrically powered vehicle that travels at a very low speed comparable to human walking speed. As it is in essence a power wheelchair, the low-speed mobility vehicle  12  will hereinafter sometimes be called the “power wheelchair  12 .” 
     Under the seat  22  are installed an electric motor  26  for driving the (rear) wheels  18  and a battery  30  for supplying operating power to the motor  26  or the like. The motor  26  and battery  30  are shown only in  FIG. 2 . The motor  26  is a DC brushless motor. 
     Between the seat  22  and body frame  20  are installed a GPS signal receiver  32  for receiving GPS (Global Positioning System) signals and a communication unit  34  communicatably connected to the remote monitoring device  16 . The GPS signal receiver  32  and communication unit  34  are shown only in  FIG. 2 . The GPS signal receiver  32  produces an output or signal representing location data and the like regarding the power wheelchair  12  acquired from the GPS signals. 
       FIG. 4  is an enlarged plan view of the operating unit  24  of the power wheelchair  12  shown in  FIGS. 2 and 3 . 
     As shown in  FIG. 4 , the operating unit  24  is equipped with handlebars  24   b  that is projected to the left and right from a dashboard  24   a , drive levers  24   c  that is also projected to the left and right for allowing the operator to input drive and stop commands, a speed setting knob  24   d  located on the dashboard  24   a  to enable the operator to set stepless speed between, for example, 1 km/h and 6 km/h, a forward-reverse switch  24   e  for allowing the operator to input power wheelchair  12  travel direction commands (forward and reverse commands) for switching the direction of travel between forward and reverse, a display (informing member)  24   f  located to be visible to the operator, and a buzzer (informer)  24   g.    
     Drive switches  24   h  are installed near the drive levers  24   c  to output signals indicating drive commands and stop commands inputted by the operator through the drive levers  24   c . A speed setting knob sensor  24   i  is installed near the speed setting knob  24   d  to produce an output or signal proportional to the speed set by the operator through the speed setting knob  24   d.    
     The operating unit  24  is further provided with an electronic keyport  24   k . When the operator brings a non-contact electronic key (IC card, not shown) near or close to the electronic keyport  24   k , the electronic keyport  24   k  reads authentication data from the memory of the electronic key, uses the authentication data to authenticate whether the electronic key is valid, and when valid, allows the power wheelchair  12  to be started. This configuration is made for preventing theft of the power wheelchair  12 , by providing an immobility feature that permits supply of starting current from the battery  30  to the motor  26  only when a valid electronic key is brought near the electronic keyport  24   k . However, as this feature is not directly related to this invention, no further explanation will be given here. 
     As shown in  FIGS. 2 to 4 , a plurality of, i.e., six lamps (light-emitting diodes (LEDs); informer)  36  are provided at suitable locations on the front, back and opposite sides of the power wheelchair  12 , namely at locations visible to the operator of the power wheelchair  12  and/or the driver of the vehicle  14  (particularly the latter). The six lamps  36  are deployed one on the front of the power wheelchair  12  near the operating unit  24 , one on the back of the backrest of the seat  22 , one on the tip of each of the left and right handlebars  24   b  projecting from the operating unit  24 , and one on each of the left and right sides of the body frame  20 . 
     The explanation of the power wheelchair  12  will be continued with reference to  FIG. 1 . The communication unit  34  is equipped with an electronic control unit (ECU)  40  for communication control (communication ECU), long-range communication equipment (first transmitter)  42  connected to the communication ECU  40 , and short-range communication equipment (third transmitter)  44 . 
     The communication ECU  40  comprises a microcomputer having a CPU, ROM, RAM and other components, none of which is shown. The communication ECU  40  is supplied with the output of the GPS signal receiver  32  (power wheelchair  12  location data) and other outputs. 
     The long-range communication equipment  42 , which has a transceiving antenna  42   a , operates in accordance with instructions from the communication ECU  40  to transmit power wheelchair  12  location data through a long-range wireless communication network (first communicator)  46  to the remote monitoring device  16  installed at an appropriate place (e.g., the company manufacturing or marketing the power wheelchair  12 ) and also receives approaching signals (explained later) sent from the remote monitoring device  16 . The long-range wireless communication network  46  is a wireless communication network using a mobile phone frequency in the vicinity of 800 MHz and is excellent in communication reliability. 
     The short-range communication equipment  44 , which is equipped with a transceiving antenna  44   a , operates in accordance with instructions from the communication ECU  40  to transmit power wheelchair  12  location data through a short-range wireless communication network (second communicator)  50  to the vehicle  14  and, as explained later, also receives vehicle  14  location data transmitted from the vehicle  14 . The short-range wireless communication network  50  is a wireless communication network that utilizes microwave communication superior to the long-range wireless communication network  46  in communication responsiveness (with low susceptibility to communication delays and similar inconveniences), specifically that uses a frequency in the vicinity of 5.8 GHz. 
     The power wheelchair  12  is also equipped with an ECU  52  for motor control (motor ECU) and an ECU  54  for display control (display ECU), each comprises a microcomputer having a CPU, ROM, RAM and the like (not shown). The ECUs  52  and  54  are communicatably connected to the communication ECU  40  through a controller area network (CAN). 
     The motor ECU  52  receives the outputs of the forward-reverse switch  24   e , drive switch  24   h , speed setting knob sensor  24   i , etc. and controls the operation of the motor  26  and driving of the power wheelchair  12  based on these outputs. The display ECU  54  is connected to the display  24   f  and controls its operation to display thereon the fact that the vehicle  14  is approaching, for example. 
     The vehicle  14  will be explained next. The vehicle  14  is equipped with an onboard navigation device  56  for guiding the vehicle  14  along a path to its destination. 
     The navigation device  56  comprises a microcomputer (abbreviated as MC in the drawing)  60  equipped with a CPU, ROM, RAM, etc., (none shown) for performing data processing, a GPS signal receiver  62  for receiving GPS signals, a map database  64  for storing route guidance map data, a display (informer)  66  for displaying map data and the like stored in the map database  64 , a voice output device (informer)  70  for providing voice route guidance, long-range communication equipment (first transmitter)  72  communicatably connected to the remote monitoring device  16  through the long-range wireless communication network  46 , and short-range communication equipment (third transmitter)  74  communicatably connected to the power wheelchair  12  through the short-range wireless communication network  50 . 
     The GPS signal receiver  62  receives GPS signals and sends an output indicating vehicle  14  location and other data obtained from the received GPS signals to the microcomputer  60 . The microcomputer  60  determines the current location (latitude, longitude and altitude) of the vehicle  14  by a known autonomous navigation method using the vehicle  14  location data and acceleration signals from a gyrosensor (not shown). 
     The microcomputer  60  searches the map data to retrieve a route from the current location of the vehicle  14  to the destination, displays the retrieved route together with the map data on the display  66 , and activates the voice output device  70  to output voice route guidance for enabling the operator of the vehicle  14  to follow the retrieved route, specifically to produce vocal utterances such as “100 meters ahead, turn right.” 
     The long-range communication equipment  72 , which has a transceiving antenna  72   a , operates in accordance with instructions from the microcomputer  60  to transmit vehicle  14  location data through the long-range wireless communication network  46  to the remote monitoring device  16  and also receives approaching signals sent from the remote monitoring device  16 . 
     The short-range communication equipment  74 , which has a transceiving antenna  74   a , operates in accordance with instructions from the microcomputer  60  to transmit vehicle  14  location data through the short-range wireless communication network  50  to the power wheelchair  12  and also receives power wheelchair  12  location data transmitted from the power wheelchair  12 . 
     The remote monitoring device  16  is equipped with a microcomputer (server)  80  having a CPU, ROM, RAM and the like (none shown) and long-range communication equipment (second transmitter)  82 . The long-range communication equipment  82  is equipped with a transceiving antenna  82   a  for exchanging signals (power wheelchair  12  and vehicle  14  location data, and approaching signals) with the transceiving antennas  42   a  and  72   a  of the power wheelchair  12  and vehicle  14 . 
     Next, the operation of the monitoring system  10  configured as set out in the foregoing will be explained. 
       FIG. 5  is a flowchart showing the operation of the remote monitoring device  16  that is a constituent of the monitoring system  10 , specifically the operation of the microcomputer  80  of the remote monitoring device  16 . The program of this flowchart is repeatedly executed at regular intervals (e.g. every 10 milliseconds). 
     First, in S 10 , it is determined whether power wheelchair  12  location data transmitted by the power wheelchair  12  was received. When the result in S 10  is YES, the program proceeds to S 12 , in which it is determined whether vehicle  14  location data transmitted by the vehicle  14  was received. 
     When the result in S 12  is YES, the program proceeds to S 14 , in which the inter-vehicle distance d between the power wheelchair  12  and vehicle  14  is calculated based on the location data received from the power wheelchair  12  and vehicle  14 . Next, in S 16 , it is determined whether the calculated inter-vehicle distance d is equal to or less than a first predetermined value d 1 . The first predetermined value d 1  is defined as an inter-vehicle distance within which the operators of the power wheelchair  12  and vehicle  14  need to be particularly cautious because their vehicles are approaching near each other. Typically, the first predetermined value d 1  is defined as 300 meters, for example. 
     When the result in S 16  is NO, the power wheelchair  12  and vehicle  14  are not close to each other, so the program is terminated, and when it is YES, the program proceeds to S 18 , in which approaching signals indicating that the power wheelchair  12  and vehicle  14  are approaching each other are transmitted through the long-range wireless communication network  46  to the power wheelchair  12  and the vehicle  14 , thereby alerting the operators of both. When the result in S 10  or S 12  is NO, the ensuing processing steps are skipped. 
     The operation of the power wheelchair  12  will be explained next. 
       FIG. 6  is a flowchart showing the operation of the power wheelchair  12 , specifically the operation of the communication ECU  40  of the power wheelchair  12 . The communication ECU  40  repeatedly executes the program of this flowchart at regular intervals (e.g. every 10 milliseconds). 
     First, in S 100 , power wheelchair (subject vehicle)  12  location data is acquired (detected) from the output of the GPS signal receiver  32 , whereafter the program proceeds to S 102 , in which the acquired power wheelchair  12  location data is transmitted through the long-range wireless communication network  46  to the remote monitoring device  16 . 
     Next, in S 104 , it is determined whether an approaching signal transmitted by the remote monitoring device  16  was received, i.e., it is determined whether the remote monitoring device  16  transmitted an approaching signal to the power wheelchair  12  upon determining proximity between the power wheelchair  12  and vehicle  14 . 
     When the result in S 104  is YES, the program proceeds to S 106 , in which the lamps  36  are flashed on and off to alert the operator of the power wheelchair  12  that it and the vehicle  14  are approaching each other. The flashing of the lamps  36  also makes the presence of the power wheelchair  12  easier for the operator of the vehicle  14  to notice (discern visually). The flashing of the lamps  36  in this situation is performed at a relatively long cycle time (e.g., 500 milliseconds, hereinafter called “first cycle time T 1 ”). 
     Next, the program proceeds to S 108 , in which the subject vehicle (power wheelchair  12 ) location data is transmitted from the short-range communication equipment  44  to the vehicle  14  through the short-range wireless communication network  50 , and to S 110 , in which the vehicle  14  location data transmitted from the vehicle  14  through the short-range wireless communication network  50  as set out later is received. Thus, upon receiving the approaching signal, the power wheelchair  12  transmits its own location data directly to the vehicle  14 . 
     Next, the program proceeds to S 112 , in which the inter-vehicle distance d between the power wheelchair  12  and the vehicle  14  is calculated based on the location data of the power wheelchair  12  itself and the vehicle  14  location data received from the vehicle  14 , and to S 114 , in which it is determined whether the calculated inter-vehicle distance d is equal to or less than a second predetermined value d 2  (e.g., 100 meters) that is set smaller than the first predetermined value d 1 . 
     When the result in S 114  is YES, the program proceeds to S 116 , in which the lamps  36  are flashed at a second cycle time T 2  (e.g., 200 milliseconds) that is set shorter than the first cycle time T 1 , the display  24   f  is operated to display a warning such as “Vehicle Approaching”, and the buzzer  24   g  is operated to sound, thereby alerting the operator of the power wheelchair  12  that the vehicle  14  is now even closer. Instead of issuing the alert through both the display  24   f  and the buzzer  24   g , it is possible to issue it through only one of them. 
     On the other hand, when the result in S 114  is NO, the program proceeds to S 118 , in which the flashing cycle time of the lamps  36  is maintained at the first cycle time T 1  if that is the current cycle time or switched to the first cycle time T 1  if the cycle time was the second cycle time T 2  in the preceding program. 
     When the result in S 104  is NO, i.e., when no approaching signal was received from the remote monitoring device  16  or reception of an approaching signal ceased because the power wheelchair  12  and vehicle  14  moved apart, the program proceeds to S 120 , in which the lamps  36  are turned off if they were flashing in the preceding program, whereafter the program is terminated. 
     The operation of the vehicle  14  will be explained next. 
       FIG. 7  is a flowchart showing the operation of the vehicle  14 , specifically the operation of the microcomputer  60  of the vehicle  14 . The program of this flowchart is repeatedly executed at regular intervals (e.g. every 10 milliseconds). 
     First, in S 200 , vehicle (subject vehicle)  14  location data is acquired (detected) from the output of the GPS signal receiver  62 , whereafter the program proceeds to S 202 , in which the vehicle  14  location data is transmitted through the long-range wireless communication network  46  to the remote monitoring device  16 . 
     Next, in S 204 , it is determined whether an approaching signal transmitted by the remote monitoring device  16  was received (whether the remote monitoring device  16  transmitted an approaching signal). When the result in S 204  is NO, the ensuing processing steps are skipped, and when it is YES, the program proceeds to S 206 , in which a warning such as “Power Wheelchair Approaching” is displayed on the display  66 , thereby alerting the operator of the vehicle  14  that the power wheelchair  12  is nearby. 
     Next, the program proceeds to S 208 , in which the subject vehicle (vehicle  14 ) location data is transmitted from the short-range communication equipment  74  to the power wheelchair  12  through the short-range wireless communication network  50 , and to S 210 , in which the power wheelchair  12  location data mentioned regarding S 110  transmitted from the power wheelchair  12  through the short-range wireless communication network  50  is received. Thus, upon receiving the approaching signal, the vehicle  14  transmits its own location data directly to the power wheelchair  12 , similarly to the power wheelchair  12 . 
     Next, the program proceeds to S 212 , in which the inter-vehicle distance d between the vehicle  14  and power wheelchair  12  is calculated based on the location data of the vehicle  14  itself and the power wheelchair  12  location data received from the power wheelchair  12 , and to S 214 , in which it is determined whether the calculated inter-vehicle distance d is equal to or less than the second predetermined value d 2  (e.g., 100 m). 
     When the result in S 214  is YES, the program proceeds to S 216 , in which the display  66  is operated to display a warning such as “Caution. Power Wheelchair Nearby.” and/or the voice output device  70  is operated to voice, thereby alerting the operator of the vehicle  14  that the power wheelchair  12  is now even closer. 
     When the result in S 214  is NO, the program proceeds to S 218 , in which use of the voice output device  70  to alert the operator of the approach of the power wheelchair  12 , if implemented in the preceding program loop, is discontinued and the alert mode is switched to the posting of the warning on the display  66  only. 
     As stated above, this embodiment is configured to have a system for monitoring a low-speed mobility vehicle (power wheelchair  12 ) and a vehicle of different type ( 14 ) from the low-speed mobility vehicle, and having a remote monitoring device ( 16 ) adapted to be connected to the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) through a first communicator (long-range wireless communication network  46 ), characterized in that: each of the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) includes: a first transmitter (long-range communication equipment  42 ,  72 , communication ECU  40 , S 102 , microcomputer  60 ,  5202 ) that transmits vehicle location data to the remote monitoring device through the first communicator; and the remote monitoring device ( 16 ) includes: a first distance calculator (S 14 ) that calculates an inter-vehicle distance (d) between the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) based on the vehicle location data transmitted from the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ); and a second transmitter (long-range communication equipment  82 , S 16 , S 18 ) that transmits an approaching signal to the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) through the first communicator indicating that the vehicles ( 12 ,  14 ) are approaching each other when the inter-vehicle distance (d) calculated by the first distance calculator is equal to or less than a first predetermined value (d 1 ). 
     Owing to this configuration, the operators of the low-speed mobility vehicle (power wheelchair)  12  and the operator of the vehicle  14  can both perceive that their vehicles are approaching one another, not only visually but also from the warnings they receive from the remote monitoring device  16 . This lightens the burden on the operators during driving and also improves driving safety. 
     In the system, each of the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) includes: an informer (lamp  36 , display  24   f , buzzer  24   g , display  66 , voice output device  70 , communication ECU  40 , S 106 , S 116 , S 118 , microcomputer  60 , S 206 , S 216 ,  5218 ) that informs an operator that the vehicles ( 12 ,  14 ) are approaching each other when receiving the approaching signal from the remote monitoring device. 
     When the remote monitoring device  16  transmits approaching signals to both the low-speed mobility vehicle (power wheelchair)  12  and the vehicle  14 , the operators of the power wheelchair  12  and vehicle  14  can each reliably be made aware that the two vehicles are approaching each other because the vehicles are equipped with the informers that inform the respective operators of the proximity of their vehicles (the power wheelchair  12  with the lamps  36 , display  24   f  and buzzer  24   g , and the vehicle  14  with the display  66  and voice output device  70 ). 
     In the system, the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) are connected with each other through a second communicator (short-range wireless communication network  50 ), and each of the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) includes: a third transmitter (short-range communication equipment  44 ,  74 , communication ECU  40 , S 108 , microcomputer  60 , S 208 ) that transmits the vehicle location data to the other ( 12  or  14 ) of the vehicles ( 12 ,  14 ) through the second communicator when receiving the approaching signal from the remote monitoring device; and a second distance calculator (communication ECU  40 , S 112 , microcomputer  60 , S 212 ) that calculates the inter-vehicle distance (d) between the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ) based on the location data transmitted from the other ( 12  or  14 ) of the vehicles ( 12 ,  14 ); and the informer informs the operator that the vehicles ( 12 ,  14 ) are further approaching each other when the inter-vehicle distance (d) calculated by the second distance calculator is equal to or less than a second predetermined value (d 2 ) that is set smaller than the first predetermined value (d 1 , S 114 , S 11 , S 214 , S 216 ). 
     Thus, when the power wheelchair  12  and vehicle  14  receive the approaching signals, each transmits its location data directly to the other. This configuration minimizes susceptibility to the effects of communication delays. Moreover, the power wheelchair  12  and vehicle  14  each uses the location data received from the other to calculate the inter-vehicle distance d between itself and the other, and the informers inform the operators that their vehicles are approaching near one another when the calculated inter-vehicle distance d is equal to or less than the second predetermined value d 2 . This configuration further enhances driving safety. 
     In the system, the informer of the low-speed mobility vehicle ( 12 ) includes a lump ( 36 ) that is flashed to inform the operators of the vehicles ( 12 ,  14 ) that the vehicles are approaching each other. This can surely make the operator of the power wheelchair  12  aware that the two vehicles are approaching each other, and also can make the operator of the vehicle  14  visibly aware that the two vehicles are approaching each other. 
     In the system, the informer of the low-speed mobility vehicle ( 12 ) flashes the lamp ( 36 ) at a first cycle (T 1 ) when receiving the approaching signal from the remote monitoring device (S 104 , S 106 ), and flashes the lamp ( 36 ) at a second cycle (T 2 ) that is set shorter than the first cycle when the inter-vehicle distance (d) calculated by the second distance calculator is equal to or less than the second predetermined value (d 2 , S 114 , S 116 ). 
     In the system, the informer of the vehicle of different type ( 14 ) includes a display ( 66 , microcomputer  60 ,  5206 ,  5216 , S 218 ) that is operated to inform the operator that the vehicles ( 12 ,  14 ) are approaching each other. 
     In the system, the informer of the vehicle of different type ( 14 ) operates the display when receiving the approaching signal from the remote monitoring device (S 204 , S 206 ), and operates the display and a voice output device ( 70 ) when the inter-vehicle distance (d) calculated by the second distance calculator is equal to or less than the second predetermined value (d 2 , S 214 , S 216 ). 
     In the system, the low-speed mobility vehicle ( 12 ) comprises a power wheelchair, and the informer of the low-speed mobility vehicle ( 12 ) includes a plurality of lamps ( 36 ) provided at locations visible to the operators of the low-speed mobility vehicle ( 12 ) and the vehicle of different type ( 14 ). 
     Although in the configuration explained in the foregoing, the power wheelchair  12  and vehicle  14  are communicatably connected to the remote monitoring device  16  through the long-range communication equipment  42  and  72 , this is not a limitation and it is possible instead adopt a configuration that uses mobile telephones possessed by the operators (driver) in place of the long-range communication equipment  42  and  72 . Specifically, the mobile telephones can be connected to the communication ECU  40  and microcomputer  60  through short-range wireless communication or the like and transmit the location data of each vehicle from the associated mobile telephone to the remote monitoring device  16 . 
     Japanese Patent Application No. 2008-292615 filed on Nov. 14, 2008, is incorporated by reference herein in its entirety. 
     While the invention has thus been shown and described with reference to specific embodiments, it should be noted that the invention is in no way limited to the details of the described arrangements; changes and modifications may be made without departing from the scope of the appended claims.