Abstract:
Disclosed are alert systems and methods for a roadway. According to one exemplary method, there is a step of receiving an identification signal from a device carried by a human having a medical condition. Subsequently, circuitry acts to conditionally cause a changeable road sign to display the medical condition, and conditionally transmit a radio warning signal to a vehicle, the radio warning signal indicating the medical condition.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates generally to systems and methods for roadways and, more particularly, to systems and methods of alerting motorists when automobiles must be operated with special care. 
   2. Description of Related Art 
   When an automobile approaches an area where the motorist needs be aware of people with special needs, warning signs may be missed. 
   SUMMARY OF THE INVENTION 
   To address the problem above, there is a method for operating with a vehicle, the method comprising the steps, performed outside of the vehicle, of receiving a signal from a device carried by a person outside of the vehicle, without actuation of the device by the person; demodulating the signal into a digital signal; comparing the digital signal to a data structure associated with a road sign in the vicinity of the vehicle; and conditionally transmitting a radio signal to the vehicle, depending on a result of the comparing step. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     References are made to the following text taken in connection with the accompanying drawings, in which: 
       FIG. 1  is a diagram of a roadway system in accordance with an exemplary by embodiment of the present invention. 
       FIG. 2  is a block diagram emphasizing circuitry associated with a road sign shown in  FIG. 1 . 
       FIG. 3  is a block diagram emphasizing aspects of the circuitry shown in  FIG. 2 . 
       FIG. 4  is a diagram showing a data structure associated with the road sign shown in  FIG. 1 . 
       FIG. 5  is a diagram showing a signal transmitted in the exemplary system. 
       FIG. 6  is a flowchart of processing performed by circuitry associated with sign  20 . 
       FIG. 7  is a block diagram emphasizing certain aspects of the system shown in  FIG. 1 . 
       FIG. 8  is a block diagram emphasizing other aspects of the system shown in  FIG. 1 . 
       FIG. 9  is a diagram emphasizing other aspects of the system shown in  FIG. 1 . 
       FIG. 10  is a diagram showing a signal transmitted in the exemplary system. 
       FIG. 11  is an image on an electronic display in the exemplary system. 
   

   The accompanying drawings which are incorporated in and which constitute a part of this specification, illustrate embodiments of the invention and, together with the description, explain the principles of the invention, and additional advantages thereof. Certain drawings are not necessarily to scale, and certain features may be shown larger than relative actual size to facilitate a more clear description of those features. Throughout the drawings, corresponding elements are labeled with corresponding reference numbers. 
   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     FIG. 1  shows system  1  in accordance with an exemplary embodiment of the present invention. Automobile  5  travels along roadway  7  having traffic sign  20 . 
   Traffic sign  20  includes antenna  215  that sends an interrogation signal  118  to passive RFID tag  15  on bracelet  2  worn by person  3 . 
   Passive RFID tag  15  has no internal power supply. An electrical current induced in its antenna by the incoming radio frequency signal  118  provides power for a CMOS integrated circuit in tag  15  to transmit a response signal  223 , which is received by antenna  220  on road sign  20 . Signal  223  includes a personal ID number that, in the case of sign  3 , identifies person  3  as someone for which sign  20  was installed. 
   Tag  15  transmits the response signal  223 , without attention or action required by person  3 . 
   In response to detecting person  3 , via signal  223 , circuitry in sign  20  transmits a signal  123 , which is received by antenna  120  on automobile  5 . Signal  123  includes a road sign ID number that, in the case of sign  20 , identifies a sign depicting a person in a wheel chair. 
   Automobile  5  also includes a global positioning system (GPS) receiver  127  ( FIG. 2 ) that receives signal  128  transmitted from a satellite, to allow circuitry in automobile  5  to determine the latitude and longitude of automobile  5 . In this Patent Application, the word circuitry encompasses dedicated hardware, and/or programmable hardware, such as a central processing unit (CPU) or reconfigurable logic array, in combination with programming data, such as sequentially fetched CPU instructions or programming data for a reconfigurable array. Thus, circuitry encompasses, for example, a general-purpose electronic processor programmed with software, acting to carry out a described function. 
     FIG. 2  shows certain aspects of circuitry in sign  20 . Circuitry  205  receives signals from receiver  222 . 
     FIG. 3  is a block diagram of circuitry  205 . Central processing unit (CPU)  250  executes program  244 , in random access memory  242 . 
     FIG. 4  shows data structure  252  in memory  242 . Structure  252  includes a list of one or more identification codes, including the code transmitted by bracelet  2 . Circuitry in other road signs, such as road signs  20 ′ and road signs  20 ″ at different roadway locations, may also store the code transmitted by bracelet  2 . 
     FIG. 5  shows a packet  330  generated by RFID tag  15  on bracelet  2 , in response to receiving the interrogation signal  118 . Packet  330  includes bits  334  encoding an identification code associating person  3  to sign  20 . 
     FIG. 6  shows a processing performed by circuitry  205  associated with sign  20 . Circuitry  205  causes transmitter  217  to transmit an interrogation signal via antenna  215 . Receiver  222  receives a radio signal and demodulates the signal into a packet containing an identification code having digits (step  5 ). Circuitry  205  executes software to determine whether the identification code corresponding to a code on the list of data structure  252  (step  10 ). If the packet does contain a code corresponding to a code on the list, circuitry  205  causes the transmitter  227  to transmit a radio warning signal to vehicles in the area, including car  5  (step  15 ). 
     FIG. 7  shows a block diagram emphasizing certain aspects of circuitry in automobile  5 . Circuitry  105  receives signals from receiver  122  and receiver  127 , and sends signals to display  110 . 
     FIG. 8  is a block diagram of circuitry  105 . Display  110  is 1024 pixel rows by 1280 pixel columns. Video ram  135  has 1024×1280 locations, a location for each pixel on display  110 . Display controller  137  has circuitry to read video ram  135  to generate and send signals to display  110 . 
   Central processing unit (CPU)  150  executes program  144 , in random access memory  142 , to display information reflecting the proximity of sign  20  relative to automobile  5 , and the terrain surrounding automobile  5 . CPU  150  displays the information on display  110 , by writing pixel data into video RAM  135 . Display controller  137  reads the pixel data from RAM  135  to send video signals to display  110 . 
     FIG. 9  shows data structure  152  in memory  142 . Structure  152  includes pixel data for displaying an image of a road sign corresponding to the image of the road associated with the circuitry described above. Structure  152  includes table  155 , which is a list of entries keyed by a road sign ID code. Each entry in table  155  includes a road sign ID code, a pointer to pixel data  160  for the road sign identified by the road sign ID code, and a pointer to audio data  165  for the road sign identified by the road sign ID code. Pixel data  160  is a group of records each containing pixel data depicting a respective road sign. Audio data  165  is a group of records each containing digitized voice data to issue an alert or warning corresponding to a respective road sign. CPU  150  uses the pointers to access a selected record of pixel data  160  and/or audio data  165 . 
     FIG. 10  shows a packet  230  generated by circuitry  205  in response to detecting person  3 . Packet  230  includes bits  232  encoding a road sign ID code, corresponding to traffic sign  20 . Packet  230  also includes bits  234  encoding the longitude and latitude of the position of traffic sign  20 , and bits  236  encoding a radius. Circuitry  205  encodes packet  230  in signal  123 . 
     FIG. 11  shows display  110 , showing the present position  5  of automobile  5 , the present position  5  being determined by GPS system  127 . Display  110  also shows a circle  238  having a center  20  determined by the latitude and longitude encoded in bits  234  and a radius determined by bits  236  of the packet transmitted by circuitry  205 . 
   Thus, the exemplary system supplements traditional road signs that warn motorists of wheel chair crossing, or deaf or blind person in the area. The system transmits a radio warning signal to vehicles, but only when the special needs person is in the area; the system does not transmit the radio warning in response to other pedestrians in the area. Thus, for example, the circuitry on the sign also has a receiver that detects a signal from an ID bracelet worn by the special needs person for whom the sign was installed. The signal from the ID bracelet encodes a serial number unique to the person. 
   When the sign circuitry detects the person&#39;s serial number, the sign circuitry transmits a warning signal to cars in the area, thereby causing an in-car system to alert the driver with an audio and/or visual display. 
   In an alternative system, instead of a unique code per person, each person&#39;s transmitter may transmit a code indicating a class of persons, such as hearing impaired, blind, or wheelchair. A central authority or registry could assign generic codes for the United States. 
   Another option is that the municipality who erects and programs the sign uses the persons drivers license or id number. Alternatively, a structure like the UPC council could be formed that would allocate a number per person. 
   Another option would be to have wireless connectivity to the internet for the sign and be able to download the entire list of people registered. 
   The road sign could include a changeable display, such as a liquid crystal display, and different warnings be displayed based on the bracelets in range; recognize the person and type of disability and display the appropriate sign. 
   When circuitry  105  in a car  5  receives a signal associated with a road sign, the motorist is also sent an alert sound that overrides vehicle audio systems to inform them of the condition, to ensure the driver uses extra caution and pays additional attention in the area. As shown in  FIG. 9 , the audio alert may include a voice signal. For example, if the road signal is for a hearing impaired person, circuitry in the car may play a verbalized announcement “Caution, hearing impaired area”. 
   The packet sent by sign circuitry  205  may also include contact information if an accident occurs, etc. 
   The alert device continues to provide feedback as to the proximity of the tag until the tag is out of range. 
   The method allows the user to override (silence for a predetermine length of time) situations where multiple alerts are received or when there is a delay in passing out of the range of the road sign. For example, the user may activate an override when waiting behind a stopped school bus. 
   The alert may be overridden if the vehicle is at a full and complete stop. 
   Thus, the packet transmitted by sign circuitry  205  identifies the Special Need, and may provide a contact name if the sign was erected for a specific person, and additional information that may assist the motorist to monitor and to handle any issues. 
   The packet transmitted by sign circuitry  205  may include personalized information: female teenager, brown hair, speed limit: 10. 
   Throughout this Patent Application, certain processing may be depicted in serial, parallel, or other fashion, for ease of description. Actual hardware and software realizations, however, may be varied depending on desired optimizations apparent to one of ordinary skill in the art. 
   Additional advantages and modifications will readily occur to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or the scope of Applicants&#39; general inventive concept. The invention is defined in the following claims. In general, the words “first,” “second,” etc., employed in the claims do not necessarily denote an order.