Method of verifying a potential detection of a man overboard event and alert verification processing apparatus

A method of configuring a radar track analyser for verification of a man overboard event, the method comprising:

• receiving a plurality of ranging track data sets;
• for each of the plurality of ranging track data sets:
• identifying a respective geometric chord intersecting a respective start point and a respective end point of a path described by a ranging track of the ranging track data;
• determining a respective height of the respective start point;
• determining a respective angle defined by a respective convergence of the respective chord and a vertical;
• recording the respective height, the respective angle and a respective verified man overboard event status corresponding to the respective height and respective angle;
• and
• identifying a first cluster of height and angle pairs and a second cluster of height and angle pairs;
• and
• determining a boundary between the first and second clusters of height and angle pairs.

An alert verification processing apparatus for verifying a potential detection of a man overboard event recorded as a moving object in a plurality of sequential frames of image data in respect of a duration of a time window, the apparatus comprising:

• a processing resource arranged to receive ranging track data in respect of the time window;
• wherein
• the processing resource is arranged to identify a geometric chord intersecting a start point and an end point of a path described by a ranging track of the ranging track data;
• the processing resource is arranged to support a comparator, an angle calculator and a height calculator;
• the height calculator is arranged to determine a height of the start point;
• the angle calculator is arranged to determine an angle defined by a convergence of the chord and a vertical;
• and
• a comparator is arranged to compare the height and the angle relative to a boundary line in order to classify the path described by the ranging track in relation to a man overboard event;
• and
• the comparator is arranged to verify the potential detection of the man overboard event in response to the classification of the path described by the ranging track.

A configuration apparatus for a radar track analyser for verification of a man overboard event, the apparatus comprising:

• a processing resource arranged to receive a plurality of ranging track data sets;
• wherein
• for each of the plurality of ranging track data sets, the processing resource is arranged to:
• identify a respective geometric chord intersecting a respective start point and a respective end point of a path described by a ranging track of the ranging track data;
• determine a respective height of the respective start point;
• determine a respective angle defined by a respective convergence of the respective chord and a vertical;
• record the respective height, the respective angle and a respective verified man overboard event status corresponding to the respective height and respective angle;
• and
• the processing resource is further arranged to identify a first cluster of height and angle pairs and a second cluster of height and angle pairs;
• and
• the processing resource is arranged to determine a boundary between the first and second clusters of height and angle pairs.