Vehicle position reporting in user defined uni-dimensional coordinate system

• US 6,012,013 A
• Filed: 05/02/1997
• Issued: 01/04/2000
• Est. Priority Date: 03/31/1995
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: McBurney, Paul
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US08/850,616
• Time in Patent Office: 977 Days
• Field of Search: 701/207, 701/208, 701/212, 701/3, 701/214-6, 701/220, 342/357.01, 342/357.02, 342/357.06, 342/357.08, 342/357.09, 342/357.1, 340/988, 340/9, 340/991, 340/3
• US Class Current: 701/207
• CPC Class Codes: G01S 19/13 Receivers
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 19/51 Relative positioning

Abstract

The method and the apparatus for the outputting in a uni-dimensional coordinate system the position coordinates and speed determined by the position and speed determining system (PSDS) are disclosed. The PSDS can include the SATPS receiver, the inertial positioning system, or the combination of both. The digital database of the geographic area is introduced by the user in the arbitrary coordinate system and is translated into the preferred coordinate system in order to define the uni-dimensional coordinate system. The large geographic area (LGA) and the small geographic area (SGA) embodiments are disclosed.

Claims

1. A method of determining location and speed of a mobile unit along a path in a Small Geographic Area (SGA) in a uni-dimensional coordinate system, said method comprising the steps of:

obtaining the coordinate fix and the speed of said mobile unit in a preferred coordinate system using a position and speed determining system (PSDS);

transforming the coordinate fix and speed of said mobile unit from said preferred coordinate system into said uni-dimensional coordinate system using a user'"'"'s computer;

retrieving a digital database of said SGA from a memory of said user'"'"'s computer, wherein said SGA comprises a plurality (m) of points in an arbitrary coordinate system, m being an integer;

defining the original connectivity of said plurality of (m) points of said SGA in said arbitrary coordinate system, wherein the connectivity of each two points passable by said mobile unit is different from the connectivity of each two points not passable by said mobile unit;

translating points inside said digital database from said arbitrary coordinate system into said preferred coordinate system by an executable program loaded into said user'"'"'s computer;

defining said uni-dimensional coordinate system in said preferred coordinate system by using said executable program of said user'"'"'s computer; and

outputting the coordinate fix and the speed of said mobile unit in said uni-dimensional coordinate system.

2. The method of claim 1, wherein said step of defining the original connectivity of said digital database further comprises the step of:

defining the connectivity in such a way that each two points have connectivity of value one if they are connectable, and each two points have connectivity of value zero if they are not connectable.

3. The method of claim 2, wherein the step of defining said uni-dimensional coordinate system in said preferred coordinate system further includes the steps of:

enumerating each said point of digital database of said SGA, wherein said enumerating process generates a plurality of numbers (1, 2, . . . , i, . . . m), and wherein each said (i) point from said digital database has the three dimensional coordinate (x_i y_i z_i) in said preferred coordinate system;

connecting each two points (k, l) from said digital database having connectivity of value one in said preferred coordinate system, k and l being integers; and

generating at least one uni-dimensional coordinate system, wherein each line created by connecting two points having connectivity of value one in said preferred coordinate system comprises said uni-dimensional coordinate system.

4. The method of claim 3, wherein the step of outputting the position location coordinates and speed of said mobile unit in said uni-dimensional coordinate system further includes the steps of:

obtaining a signal component (x₀ y₀ z₀) of the position fix of said mobile unit, wherein said position fix includes said signal component and a noise component;

outputting said signal component (x₀ y₀ z₀) of said position location along some line (s, t), wherein said line (s, t) connects points (s) and (t) in said SGA digital database having connectivity of value one, and wherein said line (s, t) represents a unique uni-dimensional coordinate system which includes said digital component (x₀ y₀ z₀) of said position fix determined by said PSDS; and

determining the distance α

between said signal component of the position fix (x₀ y₀ z₀) and point (s) along said line (s,t), and determining the distance β

between said signal component of the position fix (x₀ y₀ z₀) and point (t) along said line (s,t), wherein said pair (α

,β

) comprises a uni-dimensional coordinate of said signal component of the position fix of said mobile unit in said uni-dimensional coordinate system (s,t).

5. The method of claim 4 further including the steps of:

obtaining the speed of said mobile unit having said coordinate fix signal component (x₀ y₀ z₀); and

outputting said speed of said mobile unit corresponding to said position location (x₀ y₀ z₀) along said line (s, t) in the direction towards the point (s) or in the direction towards point (t).

6. The method of claim 1, wherein said PSDS includes a satellite positioning system (SATPS) receiver, and wherein the step of obtaining the coordinate fix and the speed of said mobile unit in said preferred coordinate system further includes the steps of:

receiving the satellite signals from a satellite positioning system (SATPS) by said SATPS receiver; and

processing information included in the satellite signals by said SATPS receiver.

7. The method of claim 1, said PSDS including an inertial position determining system (IPDS), said IPDS including a self-operating inertial sensor, wherein the step of obtaining the coordinate fix and the speed of said mobile unit in said preferred coordinate system includes the steps of:

producing positional and speed data by said self-operating inertial sensor; and

processing said positional and speed data by said inertial IPDS.

8. The method of claim 1, said PSDS including a satellite positioning system (SATPS) receiver and an inertial position determining system (IPDS), said IPDS including a self-operating inertial sensor, wherein the step of obtaining the coordinate fix and the speed of said mobile unit in said preferred coordinate system further includes the steps of:

receiving the satellite signals from a satellite positioning system (SATPS) by said SATPS receiver;

producing positional and speed data by said self-operating inertial sensor;

processing information included in the satellite signals received by said SATPS receiver; and

processing the information included in the positional data produced by said inertial sensor.

9. The method of claim 1 further including the step of:

selecting a preferred coordinate system in which said PSDS operates.

10. The method of claim 9, wherein the step of selecting said preferred coordinate system comprises the step of:

selecting a Latitude, Longitude, and Altitude (LLA) coordinate system with respect to the world geographic survey system 1984 (WGS84).

11. The method of claim 1, wherein said step of obtaining the speed of said mobile unit in a preferred coordinate system using a position and speed determining system (PSDS) further comprises the step of:

computing a three-dimensional velocity vector, a speed, said speed being a magnitude of said three-dimensional velocity, and a heading, said heading being a horizontal projection of said three-dimensional speed of said mobile unit.

12. The method of claim 10, wherein said step of obtaining the coordinate fix of said mobile unit in said preferred coordinate system using a position and speed determining system (PSDS) further comprises the step of:

computing LLA coordinates of said mobile unit, wherein LLA coordinates measurements are used for determining the signal and noise components of said position location of said mobile unit, and wherein said speed and heading measurements are used for determining said signal and said noise components of said position location of said mobile unit.

13. The method of claim 12, wherein said user computer further comprises a user computer display, said method further comprising the step of:

displaying the position fix and speed of said mobile unit in said uni-dimensional coordinate system using said user computer'"'"'s electronic display.

14. A method of determining location and speed of a mobile unit along a path in a Large Geographic Area (LGA) in a uni-dimensional coordinate system, said method comprising the steps of:

obtaining the coordinate fix and the speed of said mobile unit in a preferred coordinate system using a position and speed determining system (PSDS);

retrieving a digital database of said LGA from a base station computer, wherein said LGA comprises a plurality (m) of points in an arbitrary coordinate system, m being an integer;

wherein said LGA digital database includes the local map information corresponding to the position fix of said mobile unit;

defining the original connectivity of said plurality of (m) points of said LGA in said arbitrary coordinate system, wherein the connectivity of each two points passable by said mobile unit is different from the connectivity of each two points not passable by said mobile unit;

translating points inside said digital database from said arbitrary coordinate system into said preferred coordinate system by an executable program loaded into said user'"'"'s computer;

defining said uni-dimensional coordinate system in said preferred coordinate system by using said executable program of said user'"'"'s computer;

transforming the coordinate fix and speed of said mobile unit from said preferred coordinate system into said uni-dimensional coordinate system using a user'"'"'s computer; and

outputting the coordinate fix and the speed of said mobile unit in said uni-dimensional coordinate system.

15. The method of claim 14, wherein the step of retrieving from said base station computer storing the LGA map information the local map information corresponding to the position fix of said mobile unit further includes the step of:

physically transferring said local map information from said base station computer to said user computer by using a physical layer of a general interface.

16. The method of claim 15, wherein the step of physically transferring said local map information from said base station computer to said user computer by using a physical layer of a general interface further includes the step of:

using a conventional telephone as a physical layer.

17. The method of claim 15, wherein the step of physically transferring said local map information from said base station computer to said user computer by using physical layer of a general interface further includes the step of:

using a wireless communication system as a physical layer.

18. The method of claim 15, wherein the step of physically transferring said local map information from said base station computer to said user computer by using a physical layer of a general interface further includes the step of:

using a satellite communication system as a physical layer.