Validation and correction of auto-logged position measurements

Accurate position measurements are extremely valuable in the shipping industry for various reasons such as safety (collision avoidance), security (situational awareness), fuel-saving (weather identification), punctuality (route prediction), etc. Although GNSS (Global Navigation Satellite System) receivers installed on-board the ships are proven to be highly accurate, the data logging process may occasionally be problematic, mainly due to the complexity of the measurements and the decimal precision that is required. Data were collected from 3 years of operations of 228 Maersk Line container vessels and an analysis reveals that there is a substantial amount (≈20%) of historical position measurements sent to shore that does not reflect reality. In the study, the sources of the faulty logged position measurements are categorized and an interpolation methodology is proposed to validate and correct them by using AIS (Automatic Identification System) data. •An account of the position measurements quality recorded through the auto-logged systems installed in container vessels.•Observations from almost 200 container ships based on data collected over more than 3 years (2017–2020).•Categorization of potential position measurement issues.•Design of three validation indicators with which it can be identified if a ship carries faulty measurements in a specified time range.•Design of an algorithm/methodology for correcting the vessels with identified faulty measurements.