Roadway deviation prevention system

• US 6,064,301 A
• Filed: 02/08/1999
• Issued: 05/16/2000
• Est. Priority Date: 02/10/1998
• Status: Expired due to Fees

• Current Assignee: OKI Electric Industry Company Limited
• Original Assignee: OKI Electric Industry Company Limited
• Inventors: Takada, Hiroshi, Takahashi, Masashi
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Nguyen, Tai T.
• Application Number:
  US09/246,146
• Time in Patent Office: 463 Days
• Field of Search: 340/435, 340/438, 340/901, 340/904, 340/905, 340/933, 340/935, 340/936, 340/938, 340/941, 340/939
• US Class Current: 340/435
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A roadway deviation prevention system prevents a vehicle from deviating from the roadway. This roadway deviation prevention system has an on-vehicle transceiver which transmits a vehicle presence signal having a prescribed frequency, and data carriers, which are installed on a road, for emitting a warning signal resonating with the vehicle presence signal when the vehicle comes close to the data carriers. The on-vehicle transceiver has an annunciator which generates an alarm sound to inform the presence of the data carriers to the driver of the vehicle based on an induced voltage generated in the transceiver unit by the electromagnetic induction of the warning signal. The data carrier emits the warning signal based only on the energy generated when the resonance circuit receives the vehicle presence signal. Thus, this data carrier operates with no power source.

Claims

1. An on-vehicle transceiver for transmitting to data carriers installed in a road a vehicle presence signal for indicating presence of a vehicle, comprising:

an oscillator unit for generating said vehicle presence signal;

a transceiver unit that transmits said vehicle presence signal to said data carriers and receives a warning signal for indicating presence of said data carriers that is transmitted from said data carriers based on said vehicle presence signal;

an annunciator that informs a driver of the vehicle of the presence of said data carriers; and

a speed detector unit for detecting the speed of the vehicle;

wherein said annunciator is turned off when the detected speed is below a prescribed speed.

2. An on-vehicle transceiver as claimed in claim 1, wherein said annunciator informs the vehicle driver of the presence of said data carriers based on a voltage induced in said transceiver unit by an electromagnetic induction of said warning signal.

3. An on-vehicle transceiver as claimed in claim 2, wherein said annunciator outputs an alarm sound based on the induced voltage.

4. An on-vehicle transceiver as claimed in claim 3, further comprising a detector unit that detects a circuit voltage generated in said transceiver unit based on said induced voltage, wherein said annunciator outputs said alarm sound based on the detected circuit voltage.

5. An on-vehicle transceiver as claimed in claim 4, wherein:

said detector unit has a differential amplifier which amplifies and outputs a voltage difference between said detected circuit voltage and a prescribed reference voltage to said annunciator; and

said annunciator outputs said alarm sound based on said voltage difference.

6. An on-vehicle transceiver as claimed in claim 5, wherein said annunciator outputs said alarm sound at a level that corresponds to said voltage difference.

7. An on-vehicle transceiver to be installed in a vehicle for communicating with data carriers installed in a road, along which the vehicle is traveling, comprising:

a transceiver unit that receives from said data carriers a warning signal for indicating presence of said data carriers;

an annunciator that informs the vehicle driver of the presence of said data carriers; and

a speed detector unit for detecting a speed of the vehicle;

wherein said annunciator is turned off when the detected speed is below a prescribed speed.

8. An on-vehicle transceiver for transmitting to data carriers installed in a road a vehicle presence signal for indicating presence of a vehicle, comprising:

an oscillator unit for generating said vehicle presence signal;

a transmitter unit that transmits said vehicle presence signal to said data carriers;

a receiver unit that receives from said data carriers a warning signal for indicating presence of said data carriers;

an annunciator that informs a driver of the vehicle of the presence of said data carriers; and

a speed detector unit for detecting a speed of the vehicle;

wherein said annunciator is turned off when the detected speed is below a prescribed speed.

9. A road system having data carriers embedded therein, the data carriers informing an on-vehicle transceiver unit installed on a vehicle that the vehicle is approaching close to at least one of said data carriers, each of said data carriers comprising a resonance circuit having a capacitor and a coil, wherein:

said resonance circuit resonates in response to a vehicle presence signal transmitted from the on-vehicle transceiver unit, when the vehicle approaches close to said data carrier, and emits a warning signal which indicates the presence of said data carrier; and

said data carriers are embedded periodically in a roadside in a first row and a second row that are parallel to a traveling direction of the vehicle, the data carriers in said first row being arranged with a first prescribed separation distance, and the data carriers in said second row being arranged with a second prescribed separation distance that is shorter than said first prescribed separation distance.

10. A data carrier as claimed in claim 9, wherein said data carrier emits said warning signal based only on energy received by said resonance circuit with the vehicle presence signal.

11. A data carrier as claimed in claim 9, further comprising:

a storage capacitor for storing power generated when said resonance circuit receives said vehicle presence signal; and

a switch which turns on or shuts off said resonance circuit based on the power stored in said storage capacitor.

12. A vehicle comprising an on-vehicle transceiver which transmits a vehicle presence signal for indicating presence of said vehicle to data carriers installed in a road, wherein said on-vehicle transceiver unit has:

an oscillator unit for generating said vehicle presence signal;

a transmitter unit that transmits said vehicle presence signal to said data carriers;

a receiver unit receiving a warning signal indicating presence of said data carriers, that is transmitted from said data carriers in response to said vehicle presence signal;

an annunciator which informs a driver of the vehicle of the presence of said data carriers; and

a speed detector unit for detecting a speed of said vehicle;

wherein said annunciator is turned off when the detected speed is below a prescribed speed.

13. A vehicle as claimed in claim 12, wherein said on-vehicle transceiver is installed in a center portion of a width of said vehicle.

14. A vehicle as claimed in claim 12, wherein said on-vehicle transceiver is installed on a side portion of said vehicle.

15. A roadway deviation prevention system for preventing a vehicle from deviating from a roadway, comprising:

an on-vehicle transceiver that transmits a vehicle presence signal having a prescribed frequency; and

data carriers, installed in a road, for emitting a warning signal resonating with said vehicle presence signal when the vehicle comes close to said data carriers, said data carriers being embedded periodically in a roadside along a first row and a second row that are parallel to a traveling direction of the vehicle, the data carriers in said first row being arranged with a first prescribed separation distance, and the data carriers in said second row being arranged with a second prescribed separation distance that is shorter than said first prescribed separation distance.

16. A roadway deviation prevention system as claimed in claim 15, wherein said on-vehicle transceiver has an annunciator that informs a driver of the vehicle of the presence of said data carriers, based on said warning signal.

17. A roadway deviation prevention system as claimed in claim 16, wherein said on-vehicle transceiver has a receiver unit for receiving said warning signal, and wherein said annunciator informs the vehicle driver of the presence of said data carriers based on voltage induced in said receiving unit by an electromagnetic induction of said warning signal.

18. A roadway deviation prevention system as claimed in claim 17, wherein said annunciator outputs an alarm sound based on the induced voltage.

19. A roadway deviation prevention system as claimed in claim 15, wherein said data carriers are periodically embedded in the road.

20. A roadway deviation prevention system for preventing a vehicle from deviating from a roadway, comprising:

data carriers, installed in a road, for emitting a warning signal to said vehicle,

wherein said data carriers are periodically embedded in a roadside of the road along a first row and a second row that are parallel to a traveling direction of said vehicle, said data carriers in said first row being arranged with a first prescribed separation distance, and the data carriers in said second row being arranged with a second prescribed separation distance that is shorter than said first prescribed separation distance.