Abstract:
This invention relates to a warning system for use on board a motorized road vehicle. The warning system includes an activity detector that detects an RF signal emitted from a mobile phone when a person driving the motorized vehicle is communicating over the mobile phone. The warning system also has a display device in communication with the activity detector, the display device providing a visual indication to a motorist of another vehicle near the motorized vehicle in traffic, in a manner that allows the motorist of the other vehicle to ascertain when the person driving the motorized vehicle is using the mobile phone.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Priority is claimed from U.S. provisional patent application No. 60/351,743, filed on Jan. 24, 2002. 
    
    
     BACKGROUND OF THE INVENTION 
     1). Field of the Invention 
     This invention relates generally to a vehicular system, and more specifically to a vehicular system having a warning system on board, which is used to warn drivers that the motorist of another vehicle is actively engaged in the use of a mobile phone and thus not able to pay full attention to the duties of driving. 
     2). Discussion of Related Art 
     Cellular phones and other mobile phones have become ubiquitous. Almost one billion people in many countries have come to depend upon mobile phones, and use them in all aspects of their daily lives, including while driving their cars. 
     Talking on a mobile phone while driving is, in many ways, similar to driving while intoxicated, because one&#39;s full attention is not directed to the task of driving safely. Many accidents have been attributed to this unsafe, but popular activity. In many of these accidents, it is persons in another vehicle that are the victims. When a driver is speaking on a mobile phone, it is difficult to concentrate on the normal tasks of driving, such as maneuvering, avoiding obstacles, changing lanes, or even turning. Normal preventive actions that avoid collisions are unlikely to be performed well, and can result in accidents involving nearby cars. 
     Several features exist in modern vehicles which allow a vehicle driver to signal to others on the road a driver&#39;s intentions to perform an action that might affect others&#39; safety or traffic flow. Turn signals tell other drivers that one intends to turn shortly and in what direction. Brake lights tell a driver behind a vehicle of the vehicle driver&#39;s intention to stop. 
     Studies of the use of the high center-mounted stop lights have shown that the extra warning given to other motorists of a motorist&#39;s intention to stop has resulted in the prevention of accidents. 
     Many drivers already drive with extreme caution when a driver is spotted holding a mobile phone while driving. In some countries and in the State of New York, it is required that drivers have a hands-free mobile phone installation; however, it would then be virtually impossible to recognize from another vehicle who is on a phone and who is not. 
     SUMMARY OF THE INVENTION 
     This invention relates to a warning system for use on board a motorized road vehicle. The warning system includes an activity detector that detects a signal emitted from a mobile phone when a person driving the motorized vehicle is communicating over the mobile phone. The signal may, for example, be an RF signal or an electrical signal. The warning system also has a display device in communication with the activity detector, the display device providing a visual indication to a motorist of another vehicle near the motorized vehicle in traffic, in a manner that allows the motorist of the other vehicle to ascertain when the person driving the motorized vehicle is using the mobile phone. 
     It is possible to anticipate such unannounced and possibly dangerous maneuvers by the mobile-phone-engaged motorist if such motorist gave a signal or warning that he or she is engaged in a mobile phone conversation. However, because the mobile-phone-engaged motorist is already engaged in at least one distracting activity, the mobile-phone-engaged motorist cannot, or should not, have the burden himself or herself of activating such a warning system. It would therefore be a beneficial safety measure if an automatic warning were given to all other nearby motorists that a given driver is, by definition, engaged in a potentially distracting activity while driving. 
     To address this need, therefore, a system is proposed to present to others on the road a signal that someone in the vehicle is using a mobile phone and to do so automatically, regardless of whether the mobile phone is handheld or hands-free. This system automatically detects when a local mobile phone is in used and then activates an external signal as a warning to others that the motorist in the vehicle is engaged in a mobile phone conversation and not capable of paying full attention to the actions and responsibilities of a motorist. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is further illustrated by way of example with reference to the accompanying drawings, wherein: 
         FIG. 1  is a block diagram illustrating a vehicular system according to an embodiment of the invention, having a warning system to warn other vehicles in traffic that a person operating the vehicular system is communicating over a mobile phone; 
         FIG. 2  is a side view illustrating two vehicles, a first of the vehicles having a warning system on board which is used to warn a motorist of the second vehicle that the person driving the first vehicle is using a mobile phone; and 
         FIG. 3  is a block diagram illustrating a vehicular system according to another embodiment of the invention, having a mobile phone that transmits a special-purpose signal indicating that a person operating the vehicular system is communicating over a mobile phone. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  of the accompanying drawings illustrates a vehicular system  10 , according to an embodiment of the invention, including a motorized vehicle  12  and a warning system  14 . 
     The motorized vehicle  12  may be any road vehicle, such as a motor car, a truck, or a motorcycle. As is commonly understood, the motorized vehicle  12  has a wheeled chassis and an internal combustion engine which drives the wheeled chassis forward over a surface, or may be an electric or hybrid vehicle. The motorized vehicle  12  further has a seat in which or on which a person can sit for purposes of driving the motorized vehicle  12 . The motorized vehicle  12  further has a steering mechanism and other controls, such an accelerator or a brake control, that are all under the control of the person driving the motorized vehicle  12 . 
     A DC power supply  16  and brake lights  18  of the motorized vehicle  12  form part of the warning system  14 . The warning system  14  further includes an activity detector  20 , a timing device  22 , and a power switch  24 . 
     The purpose of the warning system  14  is to warn motorists of other vehicles in traffic when the person driving the motorized vehicle is communicating over a mobile phone  26 . No radio frequency (RF) signal is transmitted from the mobile phone  26  when the mobile phone  26  is switched off. When the mobile phone  26  is switched on in standby mode, that is, monitoring a possible call to be received but not being used for voice transmission, the normal mode of operation of many mobile phones may cause an RF signal to be briefly transmitted to tell the network that the phone is on and ready to receive or transmit. 
     When the phone user then places or receives a call, the mobile phone is then is transmit/receive mode and an RF signal  30  is then transmitted by the mobile phone  26 . The primary purpose of the RF signal  30  is to transmit voice data signals to a remote location distant from the vehicular system  10 , such as a cellular phone network. The RF signal  30  is also detected by the activity detector  20 . The activity detector  20  thus detects when the mobile phone  26  is transmitting/receiving or on standby/off. The activity detector  20  has a sensitivity that is set so that only an RF signal that is transmitted by the mobile phone  26  is detected, and RF signals transmitted from mobile phones or transmitting stations outside the motorized vehicle  12  are not detected. 
     The timing device  22  is activated by the activity detector  20  when the activity detector  20  detects that the mobile phone  26  is switched on and in transmit/receive mode. The timing device  22  is switched off by the activity detector  20  when the mobile phone  26  is no longer in transmit/receive mode. A microprocessor  27  may have a computer program  28  to assist the activity detector  20  in discriminating between signals. The activity detector  20  detects when the mobile phone  26  is in transmit/receive mode and controls other functions of the warning system. The activity detector  20  employs a microprocessor  27  and a computer program  28 . The activity detector  20  detects when the phone is being used to transmit/receive by discriminating against transient, standby-mode mobile phone RF signals from the longer-term RF signals when in transmit/receive mode. If a special-purpose signal is not present in the phone, the transmitted RF energy is detected with a signal strength sensitivity threshold that is set so that only an RF signal that is transmitted by a nearby mobile phone  26  is detected, and RF signals more distant and transmitted from mobile phones inside other vehicles outside the motorized vehicle  12  are not detected. It sets the highest threshold of the detectable RF signal. The activity detector logic directs the nature of the RF energy to respond to the different means of RF transmission used in the various industry-standard mobile phone systems such as TDMA, CDMA, GSM, PCS, 3G, 2.5G, and others. The logic in the activity detector  20  allows the brake lights to turn on in a steady, non-blinking fashion when the brake pedal is depressed by allowing the depression of the brake pedal to override the warning system. 
     The power switch  24 , in turn, is connected to the timing device  22 . The timing device  22  can, for example, switch the power switch  24  on at intervals of two seconds, the power switch  24  being switched on for one second in every period of two seconds. The timing device  22  alternately switches the power switch  24  on and off, only when the mobile phone  26  is in transmit/receive mode, and the power switch  24  is switched off when the mobile phone  26  is no longer in transmit/receive mode. 
     The brake lights  18  are connected through the power switch  24  to the power supply  16 . Power is provided through the power switch  24  to the brake lights  18  when the power switch  24  is switched on, and the brake lights  18  are switched off when the power switch  24  is switched off. It can thus be seen that the brake lights  18  are alternately switched on and off when the mobile phone  26  is in transmit/receive mode. When the mobile phone  26  is not in transmit/receive mode, the brake lights  18  are switched off. When the mobile phone  26  is not in transmit/receive mode, the brake lights  18  can only be switched on when the person operating the motorized vehicle  12  operates a brake control, such as foot brake, to decelerate the motorized vehicle  12 . The brake lights  18  will thus provide a steady light signal whenever a brake control is operated by the person operating the motorized vehicle  12 . 
     Instead of the brake light as the visual warning signal, it is possible to employ the high center-mounted stop light and the parking lights or a special warning light or lights. The mode might be a steady light instead of blinking. An audible warning signal, in addition to or instead of lights, can also be considered. 
       FIG. 2  illustrates a motorized vehicle  12  in the form of a motor car, together with another motorized vehicle  50  in traffic. The motorized vehicle  12  is driven by a person  52 , while the motorized vehicle  50  is driven by a motorist  54  and is behind the motorized vehicle  12 . The brake lights  18  of the motorized vehicle  12  provide an alternating light signal  60  that shines from the brake lights  18  through a window of the motorized vehicle  50 . The signal  60  provides a visual indication to the motorist  54  that the person  52  is using a mobile phone. The motorist  54  can discern from a blinking or flashing nature of the signal  60  that the person  52  is using a mobile phone, whereas a constant signal would indicate that the person  52  is operating a foot brake to decelerate the motorized vehicle  12 . 
     The two-second period or other appropriate duty cycle at which the brake lights  18  are switched on and off is sufficiently long to be perceptible by a person, yet sufficiently short so that a person can discriminate between a normal, constant brake light used when operating the foot brake, and a signal that indicates that the mobile is in use. 
     The motorist  54 , knowing that the person  52  may pose a danger on the road, can now take preventive action to avoid a possible collision between the vehicles  12  and  50 . Such preventive action may, for example, be decelerating the vehicle  50 . Other vehicles in the traffic to the left, the right, or in front of the motorized vehicle  12  do not see the signal  60 , and continue to drive normally. 
     In another embodiment, illustrated in  FIG. 3 , a warning system  33  utilizes a special-purpose signal  31  generated by the mobile phone  41  for the principal purpose of signaling the warning system  33 . Whereas the primary purpose of the RF signal used is to transmit/receive signals to a remote location, the special-purpose signal is intended primarily to actuate the warning system  33 . This special-purpose signal  31  can be an RF signal or a direct, wire-conducted current. A special-purpose signal would be used if such signal better assures confirmation of the transmit/receive mode, for example in CDMA transmission, or if the special-purpose signal results in simpler deployment or lower cost of the warning system. In this embodiment utilizing a special-purpose signal, the warning system  33  would include the mobile phone  41  within the warning system  33 . Other components, such as the microprocessor  39 , computer program  40 , power supply  34 , etc., are the same as in  FIG. 1 . 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative and not restrictive of the current invention, and that this invention is not restricted to the specific constructions and arrangements shown and described since modifications may occur to those ordinarily skilled in the art.