Method and apparatus of monitoring a navigation system using deviation signals from navigation sensors

• US 6,178,379 B1
• Filed: 10/31/1997
• Issued: 01/23/2001
• Est. Priority Date: 10/31/1997
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Dwyer, David B.
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US08/961,848
• Time in Patent Office: 1,180 Days
• Field of Search: 701/9, 701/11, 701/205, 701/215, 701/23, 701/41, 244/175, 244/194, 244/195, 340/945, 340/963, 342/457, 342/357.06, 342/357.12, 342/357.17, 180/168
• US Class Current: 701/205
• CPC Class Codes: G01S 19/15 Aircraft landing systems
• CPC Class Codes: G01S 19/20 Integrity monitoring, fault detection or fault isolation of space segment
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G05D 1/0202 specially adapted to aircraft
• CPC Class Codes: G08G 5/0021 located in the aircraft
• CPC Class Codes: G08G 5/0052 for cruising combined instruments indicating more than one navigational value G01C23/00

Abstract

A high integrity navigation system is created using a low integrity navigation computer monitored by a high integrity system. A navigation sensor (e.g. DGPS, GPS, ILS, MLS, and the like) is programmed with a desired trajectory. The navigation sensor calculates the vehicle position and generates a deviation signal indicative of the deviation of the vehicle from the desired trajectory. The navigation computer uses the deviation signal in the control law computations to generate steering commands for controlling the vehicle. The navigation sensor monitors the deviation of the vehicle from the desired trajectory. If the deviation exceeds a predetermined threshold, an integrity alarm signal is communicated to a display or other alarm to alert the operator.

Claims

1. A control system for an aircraft comprising:

a navigation sensor configured to receive navigational signals, and to generate a deviation signal indicative of the deviation of said aircraft from a desired trajectory; and

,

a navigation computer in communication with said navigation sensor, said computer configured to receive said deviation signal and to generate aircraft steering commands therefrom.

2. The control system according to claim 1 wherein said navigation sensor is operationally coupled to an alarm such that said alarm is activated when said deviation signal exceeds predetermined limits.

3. The control system according to claim 2 wherein:

a) said navigation computer generates display signals as a function of said deviation signals; and

,

b) said alarm is a display system in communication with said sensor and said navigation computer, said display system operable to compare said display signals and said deviation signals and notify a pilot of a malfunction in said navigation computer as a result thereof.

4. The control system according to claim 2 wherein said navigation sensor is a differential global positioning system sensor.

5. The control system according to claim 1 further comprising a control unit in communication with said navigation sensor, said control unit providing desired trajectory data to said navigation sensor.

6. The control system according to claim 5 wherein said control unit is a data link to a GPS ground station.

7. A high integrity navigation system for a vehicle comprising;

a) navigation sensor means for receiving navigation signals and generating a deviation signal indicative of the deviation of said vehicle from a desired trajectory;

b) computation means in communication with said navigation sensor means for generating vehicle steering commands as a function of said deviation signal.

8. The high integrity navigation system according to claim 7 further comprising:

a) alarm means for alerting an operator; and

,

b) where said navigation sensor means is in communication with said alarm means and includes means for detecting if said vehicle'"'"'s deviation from a desired trajectory exceeds a predetermined limit and activating said alarm means in response thereof.

9. The high integrity navigation system according to claim 7 further comprising high integrity system means, in communication with said navigation sensor means and said alarm means, monitoring said deviation signal and activating said alarm means if the deviation of said vehicle exceeds predetermined limits.

10. The high integrity navigation system according to claim 7 wherein:

a) said computation means generates display signals as a function of said deviation signals; and

,

b) said alarm means is a display system in communication with said computation means, said display system operable to compare said display signals and said deviation signals to detect inconsistencies indicative of a malfunction in said computation means and alert the operator thereof.

11. The high integrity navigation system according to claim 7 further comprising:

a) high integrity monitor means in communication with said computation means, said navigation sensor means, and said alarm means, for comparing outputs of said computation means with said deviation signals to detect a malfunction in said computation means and to activate said alert means in response thereof.

12. The high integrity navigation system according to claim 7 further comprising a control unit means, in communication with said navigation sensor means, for providing desired trajectory data to said navigation sensor means.

13. A method of navigating an aircraft having a navigation sensor, a navigation computer, and an alarm indicator, said method comprising the steps of:

a) receiving navigation signals by said navigation sensor;

b) determining aircraft deviation from a trajectory in said navigation sensor;

c) generating a deviation signal indicative of said deviation in said navigation sensor;

d) communicating said deviation signal to said navigation computer;

e) generating aircraft steering commands as a function of said deviation signals in said navigation computer;

f) comparing the deviations of step b) with predetermined limits in the navigation sensor; and

,

g) activating the alarm by the navigation sensor when the predetermined limits are exceeded.