Vehicle navigator

• US 5,856,802 A
• Filed: 06/12/1997
• Issued: 01/05/1999
• Est. Priority Date: 06/14/1996
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ikeda, Kazuhiko, Ura, Taro, Zenmyo, Keiichi, Nakano, Kenichi
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US08/871,902
• Time in Patent Office: 572 Days
• Field of Search: 342/357, 701/213, 701/214
• US Class Current: 342/357.35
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 19/52 Determining velocity

Abstract

A vehicle navigator for calculating a running distance of a vehicle from output data of an acceleration sensor, an increase of accumulated errors during the calculation of the vehicle running distance being suppressed. The vehicle navigator has an acceleration sensor for detecting an acceleration of the vehicle; a velocity calculator for calculating a first velocity of the vehicle on the basis of an acceleration detected by the acceleration sensor; a GPS receiver for receiving radio waves from artificial satellites and obtaining a second velocity; a velocity correcting unit for correcting the first velocity by using the second velocity; a running distance calculator for calculating the running distance of the vehicle from the velocity corrected by the velocity correcting unit; and a velocity limiter for setting a velocity limit value range relative to the first velocity if the second velocity cannot be obtained from the GPS receiver, in order to control the first velocity so that it does not exceed the velocity limit value range.

Claims

1. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

acceleration detecting means for detecting an acceleration of a vehicle;

velocity calculating means for calculating a first velocity of the vehicle on the basis of an acceleration detected by said acceleration detecting means;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means; and

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range, said velocity limiting means using as a reference velocity the first velocity calculated by said velocity calculating means if the second velocity is judged to be unobtainable from said receiving means, obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

2. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

velocity detecting means for detecting a first velocity of a vehicle;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means; and

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range, said velocity limiting means using as a reference velocity the first velocity calculated by said velocity calculating means if the second velocity is judged to be unobtainable from said receiving means, obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

3. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

acceleration detecting means for detecting an acceleration of a vehicle;

velocity calculating means for calculating a first velocity of the vehicle on the basis of an acceleration detected by said acceleration detecting means;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

velocity history storage means for storing velocities in the past, said velocity limiting means using as a reference velocity a mean velocity of velocities during a predetermined past time calculated from information stored in said velocity history storage means if the second velocity is judged to be unobtainable from said receiving means;

obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

4. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

velocity detecting means for detecting a first velocity of a vehicle;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

velocity history storage means for storing velocities in the past, said velocity limiting means using as a reference velocity a mean velocity of velocities during a predetermined past time calculated from information stored in said velocity history storage means if the second velocity is judged to be unobtainable from said receiving means;

obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

5. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

acceleration detecting means for detecting an acceleration of a vehicle;

velocity calculating means for calculating a first velocity of the vehicle on the basis of an acceleration detected by said acceleration detecting means;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

velocity history storage means for storing velocities in the past, said velocity limiting means using as a reference velocity a mean velocity of velocities within a predetermined past time running distance calculated from information stored in said velocity history storage means if the second velocity is judged to be unobtainable from said receiving means;

obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

6. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

velocity detecting means for detecting a first velocity of a vehicle;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means; and

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range velocity history storage means for storing velocities in the past; and

velocity history storage means for storing velocities in the past, said velocity limiting means using as a reference velocity a mean velocity of velocities within a predetermined past time running distance calculated from information stored in said velocity history storage means if the second velocity is judged to be unobtainable from said receiving means;

obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

7. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

acceleration detecting means for detecting an acceleration of a vehicle;

velocity calculating means for calculating a first velocity of the vehicle on the basis of an acceleration detected by said acceleration detecting means;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

legal limit velocity history storage means for storing legal velocities of roads, said velocity limiting means using as a reference velocity a legal limit velocity of a present road if the second velocity is judged to be unobtainable from said receiving means, obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

8. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

velocity detecting means for detecting a first velocity of a vehicle;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

legal limit velocity history storage means for storing legal velocities of roads, said velocity limiting means using as a reference velocity a legal limit velocity of a present road if the second velocity is judged to be unobtainable from said receiving means, obtaining upper and lower velocity limit values through addition and subtraction of a predetermined value to and from the reference velocity, and adopting one of the upper and lower velocity limit values as the velocity limit value.

9. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

acceleration detecting means for detecting an acceleration of a vehicle;

velocity calculating means for calculating a first velocity of the vehicle on the basis of an acceleration detected by said acceleration detecting means;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

legal limit velocity history storage means for storing legal velocities of roads, said velocity limiting means replacing the first velocity by a legal limit velocity if the first velocity calculated by said velocity calculating means takes a zero value or a minus value.

10. A vehicle navigator for receiving radio waves from artificial satellites and outputting present position information, said vehicle navigator comprising:

velocity detecting means for detecting a first velocity of a vehicle;

receiving means for receiving radio waves from artificial satellites and obtaining a second velocity;

velocity correcting means for correcting the first velocity by using the second velocity;

running distance calculating means for calculating a running distance of the vehicle from the velocity corrected by said velocity correcting means;

velocity limiting means for setting a velocity limit value range relative to the first velocity if the second velocity is judged to be unobtainable from said receiving means, in order to control the first velocity not to exceed the velocity limit value range; and

legal limit velocity history storage means for storing legal velocities of roads, said velocity limiting means replacing the first velocity by a legal limit velocity if the first velocity calculated by said velocity calculating means takes a zero value or a minus value.