METHOD OF FUNCTIONAL CONTROL OF AN INERTIAL PLATFORM OF A MOVING CRAFT

• US 20100036635A1
• Filed: 10/04/2007
• Published: 02/11/2010
• Est. Priority Date: 10/05/2006
• Status: Active Grant

• Current Assignee: Mbda France (MBDA)
• Original Assignee: Mbda France (MBDA)
• Inventors: Bourzier, Laurent
• Granted Patent: US 8,145,461 B2
• Time in Patent Office: Days
• US Class Current: 702/113
• CPC Class Codes: G01C 19/00 Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
• CPC Class Codes: G01C 21/166 Mechanical, construction or arrangement details of inertial navigation systems

Abstract

A method for verifying an inertial unit for a moving body, the unit being mounted on a movement simulator, and the method includes: theoretical modeling of the inertial unit on the movement simulator, supplying theoretical inertial data representing measurement inertial data deemed to be measured by the inertial unit; simulation modeling including modeling of the inertial unit in a real navigation environment, the simulation modeling being fed with control commands and supplying simulation inertial data representing output data from the inertial unit in real navigation environment; calculating control commands as a function of the measurement inertial data, the simulation inertial data, and the theoretical inertial data; and validating the inertial unit by comparing the path of the moving body with a reference path.

Claims

1. A method of verifying the functioning of an inertial unit for a moving body, the unit being mounted on a movement simulator and supplying in real time measurement inertial data representing a movement applied by said movement simulator, the method comprising:

theoretical modeling of the inertial unit onboard the movement simulator, said theoretical modeling being fed in real time with kinematic data actually executed by the movement simulator and supplying in real time theoretical inertial data representing said measurement inertial data deemed to be measured by the inertial unit on the movement simulator;

simulation modeling comprising modeling of the inertial unit in a real navigation environment, the simulation modeling being fed in real time with control commands and supplying in real time simulation inertial data representing output data from the inertial unit in said real navigation environment, said simulation modeling taking account of said control commands to compute a path of the moving body using the inertial unit;

calculating said control commands as a function of the measurement inertial data, the simulation inertial data, and the theoretical inertial data; and

validating the inertial unit by comparing the path of the moving body obtained using the inertial unit with a predetermined reference path.

2. A method according to claim 1, wherein the measurement inertial data includes accelerometer information from accelerometers of said inertial unit, and the theoretical inertial data includes theoretical accelerometer information.

3. A method according to claim 2, wherein the measurement inertial data further includes gyro information from gyros of said inertial unit, the theoretical inertial data includes theoretical gyro information, and the simulation inertial data includes simulation gyro information and simulation accelerometer information.

4. A method according to claim 1, wherein said control commands are calculated as a function of the inertial data defined by the sum of the measurement inertial data plus the simulation inertial data minus the theoretical inertial data.

5. A method according to claim 4, wherein the inertial unit is considered valid when the difference between the inertial data and the simulation inertial data is bounded by a predetermined threshold value.

6. A method according to claim 1, it further comprising phase advance modeling fed in real time with input kinematic commands from the simulation modeling and supplying output kinematic commands to the movement simulator for compensating an execution delay inherent to said movement simulator.

7. A method according to claim 6, wherein said input kinematic commands have a profile synchronous with that of the kinematic data and the amplitudes of said kinematic data and said input kinematic commands are consistent.

8. A method according to claim 7, further comprising masking modeling downstream from the simulation modeling and upstream from the phase advance modeling, so that the masking modeling is fed in real time with the input kinematic commands, the masking modeling supplying masked kinematic commands to the phase advance modeling to mask at least some of the phases of the movement.

9. A method according to claim 8, wherein at least some of the masked kinematic commands depend on a law internal to the masking modeling that is independent of the input kinematic commands.

15. A computer product comprising code instructions for executing steps of the control method according to claim 1 when it is executed on a computer.

10. A system for verifying the functioning of an inertial unit for a moving body, the unit being mounted on a movement simulator and supplying in real time measurement inertial data representing a movement applied by said movement simulator, the system comprising:

a theoretical model comprising modeling of the inertial unit onboard the movement simulator, the theoretical model being fed in real time with kinematic data actually executed by the movement simulator and supplying in real time theoretical inertial data representing said measurement inertial data deemed to be measured by the inertial unit on the movement simulator;

a simulation model comprising modeling of the inertial unit in a real navigation environment, the simulation model being fed in real time with control commands and supplying in real time simulation inertial data representing output data from the inertial unit in said real navigation environment, said simulation model taking account of said control commands to compute a path of the moving body using the inertial unit;

calculation means for calculating said control commands as a function of the measurement inertial data, the simulation inertial data, and the theoretical inertial data; and

validation means for validating the inertial unit by comparing the path of the moving body obtained using the inertial unit with a predetermined reference path.

11. A system according to claim 10, characterized in that the calculation means are adapted to determine said control commands as a function of the inertial data defined by the sum of the measurement inertial data plus the simulation inertial data minus the theoretical inertial data.

12. A system according to claim 10, wherein the validation means are adapted to consider the inertial unit valid when the difference between the inertial data and the simulation inertial data is bounded by a predetermined threshold value.

13. A system according to claim 10, further comprising a phase advance model fed in real time with input kinematic commands from the simulation model and supplying output kinematic commands to the movement simulator for compensating an execution delay inherent to said movement simulator.

14. A system according to claim 12, further comprising a masking model between said simulation model and said phase advance model, so that the mask modeling is fed in real time with the input kinematic commands, the masking model supplying masked kinematic commands to the phase advance model to mask at least some of the phases of the movement.