Method and apparatus for determination of misalignment between device and vessel using acceleration/deceleration
US-2016223334-A1 · Aug 4, 2016 · US
US2016116302A1 · US · A1
| Field | Value |
|---|---|
| Publication number | US-2016116302-A1 |
| Application number | US-201314655523-A |
| Country | US |
| Kind code | A1 |
| Filing date | Dec 23, 2013 |
| Priority date | Dec 26, 2012 |
| Publication date | Apr 28, 2016 |
| Grant date | — |
A practical reading order for non-experts. Skip the full description unless you need deep technical detail.
What the patent document calls the invention.
A short plain-language summary of the technical disclosure.
Who owns or filed the patent and who is credited as inventor.
Filing, priority, publication, and grant dates set the timeline.
The legal scope of protection — read this for what is actually claimed.
Technology tags used to group this patent with similar filings.
Prior art links and similar publications in this corpus.
Official abstract text for this publication.
A method for comparing two inertial guidance systems which are integral with a carrier in positions that are separated from one another and which each comprise three angular measurement sensors and three accelerometric sensors mounted along the axes of a measurement reference frame specific to each inertial guidance system, the method comprising the steps for: over a pre-determined period of time, measuring a specific force and rotations respectively with the accelerometric sensors and the angular sensors of each inertial guidance system, correcting for a cantilever effect in order to bring the reference frames to the same origin, reconstructing an inertial reference frame for each inertial guidance system using the specific force and rotations thus measured, comparing the inertial reference frames in order to determine a separation between them.
Opening claim text (preview).
1 . A method for comparing two inertial guidance systems which are integral with a carrier in positions that are separated from one another and which each comprise three angular measurement sensors and three accelerometric sensors mounted along the axes of a measurement reference frame specific to each inertial guidance system, the method comprising the steps for: over a pre-determined period of time, measuring a specific force and rotations respectively with the accelerometric sensors and the angular sensors of each inertial guidance system, correcting for a cantilever effect in order to bring the reference frames to the same origin, reconstructing an inertial reference frame for each inertial guidance system using the specific force and rotations thus measured, comparing the inertial reference frames in order to determine a separation between them. 2 . The method as claimed in claim 1 , in which the comparison of the two inertial reference frames is carried out in order to determine an instantaneous rotation matrix between the inertial reference frames. 3 . The method as claimed in claim 2 , in which biases in attitude and errors in attitude are determined based on differences between the instantaneous rotation matrix and a average rotation matrix, and the method comprises a step for introducing the biases and the errors in attitude into a model aiming to compensate the differences in attitude. 4 . The method as claimed in claim 2 , in which the reconstruction is carried out by calculating a signal corresponding to the product of the increments in speed used for the determination of the specific force and of the instantaneous rotation matrix, this signal being subsequently subjected to a low-pass filtering and an under-sampling complying with the Shannon criterion. 5 . The method as claimed in claim 2 , in which the pre-determined period is substantially equal to the error excitation period of that of the inertial guidance systems exhibiting the lowest short-term reliability. 6 . The method as claimed in claim 5 , in which, one of the inertial guidance systems being a rollover inertial guidance system, the period is equal to at least the duration of one full rollover cycle. 7 . The method as claimed in claim 5 , in which the period is of the order of at least a half-hour.
Mechanical, construction or arrangement details of inertial navigation systems · CPC title
Compensation of inertial measurements, e.g. for temperature effects · CPC title
initial alignment, calibration or starting-up of inertial devices · CPC title
Related publications grouped by family.
Answers are generated from the same data shown on this page.