Vehicle positioning and data integrating method and system thereof

• US 6,205,400 B1
• Filed: 08/13/1999
• Issued: 03/20/2001
• Est. Priority Date: 11/27/1998
• Status: Expired due to Term

• Current Assignee: American GNC Corporation
• Original Assignee: Ching-Fang Lin
• Inventors: Lin, Ching-Fang
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MANCHO, RONNIE M
• Application Number:
  US09/374,480
• Time in Patent Office: 585 Days
• Field of Search: 701/207, 701/213, 701/214, 701/215, 701/216, 701/220, 701/225, 342/357.14, 342/357.06, 342/357.05, 342/359, 342/457, 348/116, 364/428, 364/424.027
• US Class Current: 701/214
• CPC Class Codes: G01C 21/1652 with ranging devices, e.g. LIDAR or RADAR
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: G01S 19/45 by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled

Abstract

A vehicle positioning and data integrating process and system can substantially solve the problems encountered in avionics system integration, which employs integrated global positioning system/inertial measurement unit enhanced with altitude measurements to derive vehicle position, velocity, attitude, and body acceleration and rotation information. A vehicle positioning and data integrating system comprises navigation sensors and an IMU interface and preprocessing board, an altitude interface and processing board, a navigation processing board, a shared memory card, a bus arbiter, a control board, and a bus interface. The control board distributes navigation data to flight management system, flight control system, automatic dependent aurveillance, cockpit display, enhanced ground proximity warning system, weather radar, and satellite communication system.

Claims

1. An universal vehicle navigation and control box, comprising:

an inertial measurement unit (IMU) for providing inertial measurements including body angular rates and specific forces;

a global positioning system (GPS) processor for providing GPS measurements including pseudorange, carrier phase, and Doppler shift;

an altitude measurement device for providing vehicle altitude measurement;

a central navigation and control processor for processing said GPS measurements, said inertial measurements, and said vehicle altitude measurement to derive a navigation solution, which are connected with said GPS processor, said IMU, said altitude measurement device, and a data bus, comprising an IMU interface and preprocessing board, an altitude interface and processing board, a navigation processing board, a shared memory card for storing data, a bus arbiter for monitoring and managing a common bus and a data bus, and a control board for controlling the data stream mutually connected together via said common bus;

wherein

said navigation processing board is connected with said GPS processor and a data bus for receiving said GPS measurements,

said IMU interface and preprocessing board is connected with said IMU for converting said inertial measurements received from said IMU into digital data of body acceleration and rotation which are sent to said navigation processing board and said control board via said common bus,

said altitude interface and processing board is connected with said altitude measurement device for converting said altitude measurement received from said altitude measurement device to mean sea level height in digital data type which are passed to said navigation processing board and said control board through said common bus, and

said bus interface is connected between said control board and said data bus.

2. An universal vehicle navigation and control box, as recited in claim 1, wherein said central navigation and control processor is selectively connected via said data bus to a flight management system, a flight control system, an automatic dependent surveillance, a cockpit display, an enhanced ground proximity warning system, a weather radar, and a satellite communication system.

3. An universal vehicle navigation and control box, as recited in claim 1, wherein said IMU interface and preprocessing board includes an analog signal interface which is a multi-channel A/D converter circuit board for converting analog IMU signals into digital data, which comprises a multi-channel low pass filter connected to the inertial measurement unit, a multi-channel A/D converter circuit connected between the multi-channel low pass filter and the common bus, and a DMA interface connected to the common bus, wherein said analog interface further comprises a timing circuit connected between the multi-channel A/D converter circuit and the DMA interface;

wherein said analog IMU signals from said IMU are filtered by said multi-channel low pass filter, said filtered analog IMU signals are sent to said multi-channel A/D converter circuit, said timing circuit provides a sampling frequency for said multi-channel A/D converter circuit, said multi-channel A/D converter circuit samples and digitizes said filtered analog IMU signals, said timing circuit also triggers said DMA interface;

wherein after sampling and digitizing operation of said multi-channel A/D converter circuit, said DMA interface informs said navigation processing board and said control board via said common bus to get IMU data on said common bus;

wherein after receiving of the DMA signal by said navigation processing board and said control board, said multi-channel A/D converter circuit outputs said digitized IMU data on said common bus.

4. An universal vehicle navigation and control box, as recited in claim 1, wherein said IMU interface and preprocessing board includes a serial signal interface which is a multi-channel RS-485 communication control circuit board for receiving serial IMU data, which comprises an RS-485 interface circuit connected between said IMU and said common bus, and an interrupt circuit connected between said RS-485 interface circuit and said common bus;

wherein said RS-485 interface circuit receives said serial IMU signal from said IMU;

wherein once receiving operation is finished, said RS-485 interface circuit informs said interrupt circuit, said interrupt circuit then tells said navigation processing board and said control board via said common bus that said IMU data is ready;

wherein after receiving interrupt signal from said interrupt interface by said navigation processing board and said control board via said common bus, said RS-485 interface circuit outputs said IMU data on said common bus, wherein said navigation processing board and said control board get said IMU data which are body rates and accelerations from said common bus.

5. An universal vehicle navigation and control box, as recited in claim 1, wherein said IMU interface and preprocessing board includes a pulse signal interface which is a multi-channel frequency/digital converter circuit board for receiving pulse IMU signals, comprising an Inc/Dec pulse separation circuit connected to said IMU, a bus interface circuit and a interrupt circuit connected to said common bus respectively;

wherein said multi-channel frequency/digital converter circuit board further comprises a multi-channel frequency/digital circuit connected between said Inc/Dec pulse separation circuit and said bus interface circuit;

wherein said pulse IMU signals are passed to said multi-channel frequency/digital circuit via said Inc/Dec pulse separation circuit from said IMU, wherein said Inc/Dec pulse separation circuit regulates said pulse IMU signals, said multi-channel frequency/digital circuit converts said regulated pulse IMU signals into digital data;

wherein once the conversion is finished, said digital IMU data are passed to said bus interface circuit, wherein said bus interface coverts said digital IMU into common bus compatible digital data and outputs them to said common bus;

wherein said bus interface circuit triggers said interrupt circuit to generate interrupt signal, said interrupt signal informs said navigation processing board and said control board that said IMU data is ready via said common bus.

6. An universal vehicle navigation and control box, as recited in claim 1, wherein said IMU interface and preprocessing board includes a parallel digital signal interface which comprises a bus interface circuit connected between said IMU and said common bus, and an interrupt circuit connected between said bus interface circuit and said common bus;

wherein said parallel IMU signal are received by said bus interface circuit from said IMU and converted into common bus compatible data;

wherein after receiving said parallel IMU data, said bus interface circuit triggers said interrupt circuit to generate interrupt signal which is used to inform said navigation processing board and said control board via said common bus that said IMU data is ready;

wherein said bus interface circuit outputs said IMU data to said common bus, and said navigation processing board and said control board receive said IMU data from said common bus.

7. An universal vehicle navigation and control box, as recited in claim 2, wherein said IMU interface and preprocessing board includes an analog signal interface which is a multi-channel A/D converter circuit board for converting analog IMU signals into digital data, which comprises a multi-channel low pass filter connected to the inertial measurement unit, a multi-channel A/D converter circuit connected between the multi-channel low pass filter and the common bus, and a DMA interface connected to the common bus, wherein said analog interface further comprises a timing circuit connected between the multi-channel A/D converter circuit and the DMA interface;

wherein said analog IMU signals from said IMU are filtered by said multi-channel low pass filter, said filtered analog IMU signals are sent to said multi-channel A/D converter circuit, said timing circuit provides a sampling frequency for said multi-channel A/D converter circuit, said multi-channel A/D converter circuit samples and digitizes said filtered analog IMU signals, said timing circuit also triggers said DMA interface;

wherein after sampling and digitizing operation of said multi-channel A/D converter circuit, said DMA interface informs said navigation processing board and said control board via said common bus to get IMU data on said common bus;

wherein after receiving of the DMA signal by said navigation processing board and said control board, said multi-channel A/D converter circuit outputs said digitized IMU data on said common bus.

8. An universal vehicle navigation and control box, as recited in claim 2, wherein said IMU interface and preprocessing board includes a serial signal interface which is a multi-channel RS-485 communication control circuit board for receiving serial IMU data, which comprises an RS-485 interface circuit connected between said IMU and said common bus, and an interrupt circuit connected between said RS-485 interface circuit and said common bus;

wherein said RS-485 interface circuit receives said serial IMU signal from said IMU;

wherein once receiving operation is finished, said RS-485 interface circuit informs said interrupt circuit, said interrupt circuit then tells said navigation processing board and said control board via said common bus that said IMU data is ready;

wherein after receiving interrupt signal from said interrupt interface by said navigation processing board and said control board via said common bus, said RS-485 interface circuit outputs said IMU data on said common bus, wherein said navigation processing board and said control board get said IMU data which are body rates and accelerations from said common bus.

9. An universal vehicle navigation and control box, as recited in claim 2,

wherein said IMU interface and preprocessing board includes a pulse signal interface which is a multi-channel frequency/digital converter circuit board for receiving pulse IMU signals, comprising an Inc/Dec pulse separation circuit connected to said IMU, a bus interface circuit and a interrupt circuit connected to said common bus respectively;

wherein said multi-channel frequency/digital converter circuit board further comprises a multi-channel frequency/digital circuit connected between said Inc/Dec pulse separation circuit and said bus interface circuit;

wherein said pulse IMU signals are passed to said multi-channel frequency/digital circuit via said Inc/Dec pulse separation circuit from said IMU, wherein said Inc/Dec pulse separation circuit regulates said pulse IMU signals, said multi-channel frequency/digital circuit converts said regulated pulse IMU signals into digital data;

wherein once the conversion is finished, said digital IMU data are passed to said bus interface circuit, wherein said bus interface coverts said digital IMU into common bus compatible digital data and outputs them to said common bus;

wherein said bus interface circuit triggers said interrupt circuit to generate interrupt signal, said interrupt signal informs said navigation processing board and said control board that said IMU data is ready via said common bus.

10. An universal vehicle navigation and control box, as recited in claim 2,

wherein said IMU interface and preprocessing board includes a parallel digital signal interface which comprises a bus interface circuit connected between said IMU and said common bus, and an interrupt circuit connected between said bus interface circuit and said common bus;

wherein said parallel IMU signal are received by said bus interface circuit from said IMU and converted into common bus compatible data;

wherein after receiving said parallel IMU data, said bus interface circuit triggers said interrupt circuit to generate interrupt signal which is used to inform said navigation processing board and said control board via said common bus that said IMU data is ready;

wherein said bus interface circuit outputs said IMU data to said common bus, and said navigation processing board and said control board receive said IMU data from said common bus.

11. An universal vehicle navigation and control box, as recited in claim 2, said control board controls and distributes navigation data to other avionics systems;

wherein said control board receives said body acceleration and rotation data from said IMU interface and preprocessing board, receives said vehicle altitude data from said altitude interface and processing board via said common bus, and receives said vehicle position, velocity, attitude, and time data from said navigation board via said common bus;

wherein said control board sends vehicle position, velocity, attitude, and time data to said flight management system via said bus interface and said data bus;

wherein said control board sends said vehicle velocity, attitude, and said digital body acceleration and rotation data to said flight control system via said bus interface and said data bus;

wherein said control board sends said vehicle position and time data to said automatic dependence surveillance via said bus interface and said data bus;

wherein said control board sends said vehicle position, velocity, attitude, and time data to said cockpit display via said bus interface and said data bus;

wherein said control board sends said vehicle position, velocity, and attitude data to said enhanced ground proximity warning system via said bus interface and said data bus;

wherein said control board sends said vehicle attitude and said body acceleration data to said weather radar via said bus interface and said data bus;

wherein said control board sends said vehicle position and attitude data to said satellite communication system via said bus interface and said data bus.

12. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said altitude measurement device includes a barometric device and a radar altimeter;

wherein said barometric device provides said vehicle altitude above mean sea level (MSL), and said radar altimeter provides said vehicle altitude above terrain.

13. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said altitude interface and processing board includes a barometric device interface for converting measurement of said barometric device into digital data which is said vehicle altitude above mean sea level (MSL);

said barometric device interface is a multi-channel A/D converter circuit board, which comprises a low pass filter connected to said barometric device, a A/D converter circuit connected between said low pass filter and said common bus, and a DMA interface connected to said common bus;

wherein said barometric device interface further comprises a timing circuit connected between said A/D converter circuit and said DMA interface.

14. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said altitude interface and processing board includes a radar altimeter interface for converting measurement of said radar altimeter into said vehicle altitude above MSL;

wherein said radar altimeter interface comprises a data fusion module connected between said radar altimeter and said common bus, and a terrain database connected between said data fusion module and said common bus;

wherein said radar altimeter generates said vehicle altitude above terrain;

wherein said terrain database receives said vehicle position information from said navigation processing board through said common bus, and said database queries a terrain elevation above MSL and output it to said data fusion module;

wherein said data fusion module combines said vehicle altitude above terrain from said radar altimeter and said terrain elevation from said terrain database to generate said vehicle altitude above MSL.

15. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said navigation processing board comprises an INS processor, a Kalman filter, a carrier phase integer ambiguity resolution module;

wherein said IMU measurements coming from said IMU interface and preprocessing board are collected by said INS processor to perform inertial navigation processing;

wherein said vehicle velocity and acceleration data derived by said INS processor are sent to said GPS processor to aid carrier phase and code tracking loops of a microprocessor of said GPS processor;

wherein said Kalman filter collects said vehicle altitude from said altitude interface and processing board, output of said INS processor, and said GPS measurements which are carrier phase, pseudorange, and Doppler shift from said GPS processor to perform integrated filtering processing to derive position error and attitude error;

wherein said position error and said attitude error are sent to said INS processor to correct said inertial navigation solution;

wherein said carrier phase integer ambiguity resolution module receives said corrected inertial navigation solution from said INS processor, said GPS measurements from said GPS processor, and output of said Kalman filter to fix a GPS satellite carrier phase integer ambiguity number;

wherein said fixed GPS satellite carrier phase integer ambiguity number is sent to said Kalman filter.

16. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said navigation processing board comprises an INS processor, and a Kalman filter;

wherein said IMU measurements coming from said IMU interface and preprocessing board are collected by said INS processor to perform inertial navigation processing;

wherein said vehicle velocity and acceleration data derived by said INS processor are sent to said GPS processor to aid carrier phase and code tracking loops of a microprocessor of said GPS processor;

wherein said Kalman filter collects said vehicle altitude from said altitude interface and processing board, output of said INS processor, and said GPS measurements which are pseudorange and Doppler shift from said GPS processor to perform integrated filtering processing to derive position error and attitude error;

wherein said position error and said attitude error are sent to said INS processor to correct said inertial navigation solution.

17. An universal vehicle navigation and control box, as recited in anyone of claims 1 to 11, wherein said navigation processing board comprises an INS processor and a Kalman filter;

wherein said IMU measurements coming from said IMU interface and preprocessing board are collected by said INS processor to perform inertial navigation processing;

wherein said Kalman filter collects said vehicle altitude from said altitude interface and processing board, output of said INS processor, and said GPS measurements which pseudorange and Doppler shift from said GPS processor to perform integrated filtering processing to derive position error and attitude error;

wherein said position error and said attitude error are sent to said INS processor to correct said inertial navigation solution.

18. A vehicle positioning and data integrating method, comprising the steps of:

(a) performing GPS processing and receiving GPS measurements, including pseudorange, carrier phase, Doppler shift, and time, from a global positioning system processor, and passing said GPS measurements to a navigation processing board of a central navigation processor;

(b) receiving inertial measurements, including body angular rates and specific forces from an inertial measurement unit, converting said inertial measurements into digital data of body acceleration and rotation by an IMU interface and preprocessing board, and sending said digital data of body acceleration and rotation to said navigation processing board and a control board via a common bus;

(c) receiving an altitude measurement from an altitude measurement device, converting said altitude measurement to a vehicle altitude above mean sea level (MSL) in digital data type by an altitude interface and processing board, and passing said vehicle altitude above mean sea level to said navigation processing board and said control board through said common bus;

(d) performing an INS processing in an INS processor;

(e) blending an output of said INS processor, said altitude measurement, and said GPS measurements in a kalman filter;

(g) feeding back an output of said kalman filter to said INS processor to correct said INS navigation solution;

(h) injecting said velocity and acceleration data from said INS processor into a signal processor of said global positioning system processor to aid code and carrier phase tracking of the global positioning system satellite signals;

(i) injecting said output of the signal processor of said global positioning system processor, said output of said INS processor, said output of said kalman filter into a carrier phase integer ambiguity resolution module to fix a global positioning system satellite signal carrier phase integer ambiguity number;

(j) outputting said carrier phase integer number from said carrier phase integer ambiguity resolution module into said kalman filter to further improve the positioning accuracy; and

(k) outputting said navigation data including vehicle velocity, position, altitude, heading and time from said INS processor to said control board through said common bus.

19. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle position, velocity, attitude, heading, and time data to a flight management system.

20. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle velocity, attitude, body acceleration and rotation data to a flight control system.

21. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle position and time data to an automatic dependent surveillance.

22. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle position, velocity, and attitude data to an enhanced ground proximity warning system.

23. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle attitude and body acceleration data to a weather radar.

24. A vehicle positioning and data integrating method, as recited in claim 18, after step (k), further comprising the step of:

sending said vehicle platform position and attitude data to said satellite communication system.

25. A vehicle positioning and data integrating method, comprising the steps of:

(a) performing GPS processing and receiving GPS measurements, including pseudorange, Doppler shift, and time, from a global positioning system processor and passing said GPS measurements to a navigation processing board of a central navigation processor;

(b) receiving inertial measurements, including body angular rates and specific forces, from an inertial measurement unit, converting said inertial measurements into digital data of body acceleration and rotation by an IMU interface and preprocessing board, and sending said digital data of body acceleration and rotation to said navigation processing board and a control board via a common bus;

(c) receiving an altitude measurement from an altitude measurement device, converting said altitude measurement to a vehicle altitude above mean sea level (MSL) in digital data type by an altitude interface and processing board, and passing said digital data of vehicle altitude above mean sea level to said navigation processing board and said control board through said common bus;

(d) performing INS processing in an INS processor;

(e) blending an output of said INS processor, said altitude measurement, and said GPS measurements in a kalman filter;

(f) feeding back an output of said kalman filter to said INS processor to correct said INS navigation solution;

(g) injecting said velocity and acceleration data from said INS processor into a signal processor of said global positioning system processor to aid code and carrier phase tracking of the global positioning system satellite signals; and

(h) outputting said navigation data including vehicle velocity, position, altitude, heading and time from said INS processor to said control board through said common bus.

26. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle position, velocity, attitude, heading, and time data to a flight management system.

27. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle velocity, attitude, body acceleration and rotation data to a flight control system.

28. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle position and time data to an automatic dependent surveillance.

29. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle position, velocity, and attitude data to an enhanced ground proximity warning system.

30. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle attitude and body acceleration data to a weather radar.

31. A vehicle positioning and data integrating method, as recited in claim 25, after step (h), further comprising the step of:

sending said vehicle platform position and attitude data to said satellite communication system.

32. A vehicle positioning and data integrating method, comprising the steps of:

(a) performing GPS processing and receiving GPS measurements, including position, velocity and time, from a global positioning system processor and passing said GPS measurements to a navigation processing board of a central navigation processor;

(b) receiving inertial measurements, including body angular rates and specific forces, from an inertial measurement unit, converting said inertial measurements into digital data of body acceleration and rotation by an IMU interface and preprocessing board, and sending said digital data of body acceleration and rotation to said navigation processing board and a control board via a common bus;

(c) receiving an altitude measurement from an altitude measurement device, converting said altitude measurement to digital data of vehicle altitude above mean sea level (MSL) by an altitude interface and processing board, and passing said digital data of vehicle altitude above mean sea level to said navigation processing board and said control board through said common bus;

(d) performing INS processing in an INS processor;

(e) blending an output of said INS processor, said altitude measurement, and said GPS measurements in a kalman filter;

(f) feeding back an output of said kalman filter to said INS processor to correct said INS navigation solution; and

(g) outputting said navigation data, including vehicle velocity, position, altitude, heading and time, from said INS processor to said control board through said common bus.

33. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle position, velocity, attitude, heading, and time data to a flight management system.

34. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle velocity, attitude, body acceleration and rotation data to a flight control system.

35. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle position and time data to an automatic dependent surveillance.

36. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle position, velocity, and attitude data to an enhanced ground proximity warning system.

37. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle attitude and body acceleration data to a weather radar.

38. A vehicle positioning and data integrating method, as recited in claim 32, after step (g), further comprising the step of:

sending said vehicle platform position and attitude data to said satellite communication system.