Lateral positioning detecting apparatus for moving body

• US 6,032,110 A
• Filed: 07/14/1998
• Issued: 02/29/2000
• Est. Priority Date: 08/28/1997
• Status: Expired due to Fees

• Current Assignee: Nippon Soken, Inc.
• Original Assignee: Nippon Soken, Inc.
• Inventors: Kitahara, Takahide, Ishihara, Toshihisa, Tsuge, Shigeto
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): Bui, Bryan
• Application Number:
  US09/114,931
• Time in Patent Office: 595 Days
• Field of Search: 702/150, 702/94, 702/95, 701/23, 701/207, 180/167-168, 324/207.11-207.14, 324/207.22, 324/236, 324/245, 324/246
• US Class Current: 702/150
• CPC Class Codes: G01B 7/31 for testing the alignment of axes
• CPC Class Codes: G05D 1/0261 using magnetic plots

Abstract

Markers each comprising an electromagnetic coil are installed on the surface of a road at a lateral center line of a running lane of the road at predetermined intervals. Provided for each of the markers, a driving signal generating circuit drives the associated marker so that the marker transmits an alternating current magnetic field. Alternating current magnetic field receiving devices each comprising an electromagnetic coil are installed on the front bumper of a vehicle at positions symmetrical with respect to the lateral center line of the vehicle. While the vehicle is running, the alternating current magnetic field receiving devices sequentially receive the alternating current magnetic fields generated by the markers one field after another. A microcomputer receives detection voltages generated by the alternating current magnetic field receiving devices through detection circuits and determines the lateral position of the vehicle from the detection voltages.

Claims

1. A lateral position detecting apparatus for detecting a lateral position of a moving body, comprising:

alternating current magnetic field transmitting devices installed on a surface of a running path of the moving body at a lateral center line of a running lane of the running path at predetermined intervals in a longitudinal direction;

driving means for driving one of the alternating current magnetic field transmitting devices so that the alternating current magnetic field transmitting device transmits an alternating current magnetic field;

alternating current magnetic field receiving means installed on a lower portion of the moving body for sequentially receiving the alternating current magnetic fields transmitted by the alternating current magnetic field transmitting devices while the moving body is moving; and

lateral position detecting means provided on the moving body for detecting a lateral position of the moving body based on the alternating current magnetic fields sequentially received by the alternating current magnetic field receiving means,

wherein;

the alternating current magnetic field transmitting devices are each a magnetic field transmitting coil having an axis oriented in a vertical direction against the running path;

the driving means each includes oscillation means driven by electric power supplied by a power supply into oscillation and a driving circuit driven by the oscillation for driving one of the magnetic field transmitting coils associated with the driving means so that the magnetic field transmitting coil transmits an alternating current magnetic field;

the alternating current magnetic field receiving means includes a pair of magnetic field receiving coils installed on the lower portion of the moving body at positions symmetrical with respect to a lateral center line of the moving body for receiving the alternating current magnetic fields transmitted by the transmitting coils while the moving body is moving;

the lateral position detecting means includes voltage detecting means for detecting the alternating current magnetic fields received by the magnetic field receiving coils as detection voltages, and distance determining means for determining a distance from the lateral center line of the moving body to the axis of the magnetic field transmitting coil from the detection voltages by using data representing relations among the distance, one of the detection voltages and a ratio of the another of the detection voltages to the one of the detection voltages; and

the distance determined by the distance determining means is used as a basis for detecting the lateral position of the moving body.

2. The lateral position detecting apparatus according to claim 1, wherein:

the driving means each have a first capacitor for constituting a resonance circuit in conjunction with the magnetic field transmitting coil;

the oscillation of the oscillation means causes the resonance circuit to resonate, causing the magnetic field transmitting coil to transmit an alternating current magnetic field as a resonance magnetic field;

the alternating current magnetic field receiving means has second capacitors provided for the magnetic field receiving coils to constitute resonance circuits in conjunction with the respective magnetic field receiving coils and the resonance circuits resonate when receiving the resonance magnetic field; and

the voltage detecting means detects an amplitude of a resonance output of each second capacitor of the alternating current magnetic field receiving means associated with the voltage detecting means as the detection voltage.

3. A lateral position detecting apparatus for detecting a lateral position of a moving body, the apparatus comprising:

an electric power conveying magnetic field transmitting device installed on a lower portion of the moving body moving along a surface of a running path;

electric power conveying magnetic field transmitting device driving means for driving the electric power conveying magnetic field transmitting device so that the electric power conveying magnetic field transmitting device transmits an alternating current magnetic field as an electric power conveying magnetic field;

alternating current magnetic field transmitting devices installed on the surface of the running path of the moving body at a lateral center line of a running lane of the running path at predetermined intervals for sequentially receiving the electric power conveying magnetic field transmitted by the electric power conveying magnetic transmitting device while the moving body is moving;

alternating current magnetic field transmitting device driving means for sequentially driving the alternating current magnetic field transmitting devices based on the electric power conveying magnetic field received from the electric power conveying magnetic field transmitting devices so that the alternating current magnetic field transmitting devices each transmit an alternating current magnetic field;

alternating current magnetic field receiving means installed on the lower portion of the moving body for sequentially receiving the alternating current magnetic fields transmitted by the alternating current magnetic field transmitting devices while the moving body is moving; and

lateral position detecting means provided on the moving body for detecting the lateral position of the moving body on the basis of the alternating current magnetic fields sequentially received by the alternating current magnetic field receiving means,

wherein;

the electric power conveying magnetic field transmitting device is an electric power conveying magnetic field transmitting coil;

the electric power conveying magnetic field transmitting device driving means drives the electric power conveying magnetic field transmitting coil so that the electric power conveying magnetic field transmitting coil transmits the electric power conveying magnetic field;

the alternating current magnetic field transmitting devices are each an alternating current magnetic field transmitting coil;

the alternating current magnetic field transmitting device driving means each includes electric power accumulating means for accumulating electric power conveyed by the electric power conveying magnetic field received by the alternating current magnetic field transmitting coil and oscillation means which receives electric power from the electric power accumulating means and oscillates, driving the alternating current magnetic field transmitting coil to transmit the alternating current magnetic field;

the alternating current magnetic field receiving means includes a pair of alternating current magnetic field receiving coils installed on the lower portion of the moving body at positions symmetrical with respect to a lateral center line of the moving body;

the lateral position detecting means includes voltage detecting means for detecting the alternating current magnetic field received by the alternating current magnetic field receiving coils respectively and outputting each result of detection as a detection voltage, and distance determining means for determining a distance from the lateral center line of the moving body to the axis of the alternating current magnetic field transmitting coil from the detection voltages by using data representing relations among distance, one of the detection voltages and a ratio of another of the detection voltages to the one of the detection voltages; and

the distance determined by the distance determining means is used for detecting the lateral position of the moving body.

4. The lateral position detecting apparatus according to claim 3, wherein the electric power conveying magnetic field transmitting device driving means includes a periodically driving means for driving the electric power conveying magnetic field transmitting device so that the electric power conveying magnetic field transmitting device transmits the electric power conveying magnetic field in a period corresponding to a running speed of the moving body.

5. The lateral position detecting apparatus according to claim 3, wherein the alternating current magnetic field transmitting device driving means drives the alternating current magnetic field transmitting devices so that the alternating current magnetic field transmitting devices each transmit the alternating current magnetic field at a frequency different from a frequency at which the electric power conveying magnetic field is transmitted by the electric power conveying magnetic field transmitting device.

6. The lateral position detecting apparatus according to claim 3, wherein:

the alternating current magnetic field transmitting device driving means each have a capacitor constituting a resonance circuit in conjunction with the magnetic field transmitting coil so that the resonance circuit is driven by the electric power conveying magnetic field received by the alternating current magnetic field transmitting coil into resonance;

the alternating current magnetic field receiving means has capacitors provided for the alternating current magnetic field receiving coils to constitute resonance circuits in conjunction with the respective magnetic field receiving coils so that the resonance circuits resonate when receiving the resonance magnetic field; and

the voltage detecting means detects the amplitude of a resonance output of the capacitors of the alternating current magnetic field receiving means associated with the voltage detecting means as the detection voltage.

7. A lateral position detecting apparatus for detecting a lateral position of a moving body, the apparatus comprising:

an electric power conveying magnetic field transmitting device installed on a lower portion of the moving body moving along a surface of a running path;

electric power conveying magnetic field transmitting device driving means for driving the electric sower conveying magnetic field transmitting device so that the electric power conveying magnetic field transmitting device transmits an alternating current magnetic field as an electric power conveying magnetic field;

alternating current magnetic field transmitting devices installed on the surface of the running path of the moving body at a lateral center line of a running lane of the running path at predetermined intervals for sequentially receiving the electric power conveying magnetic field transmitted by the electric power conveying magnetic transmitting device while the moving body is moving;

alternating current magnetic field transmitting device driving means for sequentially driving the alternating current magnetic field transmitting devices based on the electric power conveying magnetic field received from the electric power conveying magnetic field transmitting devices so that the alternating current magnetic field transmitting devices each transmit an alternating current magnetic field;

alternating current magnetic field receiving means installed on the lower portion of the moving body for sequentially receiving the alternating current magnetic fields transmitted by the alternating current magnetic field transmitting devices while the moving body is moving; and

lateral position detecting means provided on the moving body for detecting the lateral position of the moving body on the basis of the alternating current magnetic fields sequentially received by the alternating current magnetic field receiving means,

wherein;

the electric power conveying magnetic field transmitting device is an electric power conveying magnetic field transmitting coil;

the electric power conveying magnetic field transmitting device driving means drives the electric power conveying magnetic field transmitting coil so that the electric power conveying magnetic field transmitting coil transmits the electric power conveying magnetic field;

the alternating current magnetic field transmitting devices are each an alternating current magnetic field transmitting coil;

the alternating current magnetic field transmitting device driving means each includes electric power accumulating means for accumulating electric power conveyed by the electric power conveying magnetic field received by the alternating current magnetic field transmitting coil and oscillation means which receives electric power from the electric power accumulating means and oscillates, driving the alternating current magnetic field transmitting coil to transmit the alternating current magnetic field;

the alternating current magnetic field receiving means includes a pair of first alternating current magnetic field receiving coils installed on the lower portion of the moving body at positions symmetrical with respect to the lateral center line of the moving body and having an axis perpendicular to the running path, and a pair of second alternating current magnetic field receiving coils installed on the lower portion of the moving body and crossing the first alternating current magnetic field receiving coils at centers of the first alternating current magnetic field receiving coils respectively;

the lateral position detecting means includes voltage detecting means for detecting the alternating current magnetic fields received by the first alternating current magnetic field receiving coils and outputting each result of detection as a first detection voltage and second detection voltage, and distance determining means for determining a distance from the lateral center line of the moving body to the axis of the alternating current magnetic field transmitting coil from the first and second detection voltages by using data representing relations among the distance, one of the first detection voltages and corresponding one of the second detection voltages; and

the distance determined by the distance measuring means is used for detecting the lateral position of the moving body.

8. The lateral position detecting apparatus according to claim 7, wherein:

the alternating current magnetic field transmitting device driving means each have a capacitor constituting a resonance circuit in conjunction with the magnetic field transmitting coil so that the resonance circuit is driven by the electric power conveying magnetic field received by the alternating current magnetic field transmitting coil into resonance;

the alternating current magnetic field receiving means has first and second capacitors constituting resonance circuits in conjunction with the first alternating current magnetic field receiving coils respectively so that the resonance circuits resonate when receiving the alternating current magnetic fields received by the first and second alternating current magnetic field receiving coils; and

the voltage detecting means detects amplitudes of resonance outputs of the first capacitors as the first detection voltages and detects amplitudes of resonance outputs of the second capacitors as the second detection voltages.

9. The lateral position detecting apparatus according to claim 7, wherein the electric power conveying magnetic field transmitting device driving means includes a periodically driving means for driving the electric power conveying magnetic field transmitting device so that the electric power conveying magnetic field transmitting device transmits the electric power conveying magnetic field in a period corresponding to a running speed of the moving body.

10. The lateral position detecting apparatus according to claim 7, wherein the alternating current magnetic field transmitting device driving means drives the alternating current magnetic field transmitting devices so that the alternating current magnetic field transmitting devices each transmit the alternating current magnetic field at a frequency different from a frequency at which the electric power conveying magnetic field is transmitted by the electric power conveying magnetic field transmitting device.