Adaptive riser angle position reference system
US4351027A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1980 |
| Grant date | Sep 21, 1982 |
| Priority date | — |
| Expiry date | Aug 13, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D1/0208
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An adaptive riser angle position reference system and method for determining the horizontal position of a marine vessel relative to an underwater wellhead from angular deviations from vertical of a riser between the vessel and the wellhead are disclosed. The system comprises sensors for determining deviation from vertical of the riser at positions proximate the wellhead and the vessel and a compensation filter for adaptively filtering signals indicative of the lower and upper riser angles in accordance with filter coefficients which are determined by riser parameters. The filter coefficients are established by riser parameter identification means which effectively compares riser response, as indicated by the lower and upper riser angles, with the responses of a plurality of riser models, and selects filter coefficients corresponding to the most accurate model.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.