Abstract: A portion of a line from a line laying vessel to a touchdown support point on or near to the seabed is imaged with a 3 dimensional sonar imaging system to produce coordinates of a series of touchdown points using a time sequence of sonar images, and the time series of touchdown points is recorded.

Abstract: Reflected sonar signals arising from one or more possible unknown objects are distinguished according to a first criterion, and possible shapes each having a defined unique associated point are assigned each of the possible unknown objects. Then the three dimensional points are tracked by the sonar system.

Abstract: A sonar system comprising a sonar transmitter, a very large array two dimensional sonar receiver, and a beamformer section transmits a series of sonar pings into an ensonified volume of fluid at a rate greater than 5 pings per second, receives sonar signals reflected and scattered from objects in the ensonified volume, and beamforms the reflected signals to provide a video presentation and/or to store the beamformed data for later use. The parameters controlling the sonar system are changed so that the beamformer section treats the data from the receiver section with more than one set of parameters. The stream of data is treated either in parallel or in series by different beamforming methods so that at least one beam from the beamformer has more than one value.

Abstract: A sonar system comprising a sonar transmitter, a very large array two dimensional sonar receiver, and a beamformer section transmits a series of sonar pings into an ensonified volume of fluid at a rate greater than 5 pings per second, receives sonar signals reflected and scattered from objects in the ensonified volume, and beamforms the reflected signals to provide a video presentation and/or to store the beamformed data for later use. The parameters controlling the sonar system are changed so that the beamformer section treats the data from the receiver section with more than one set of parameters per ping and/or neighboring pings. The stream of data is treated either in parallel or in series by different beamforming methods so that at least one beam from the beamformer has more than one value.

Abstract: A sonar system comprising a sonar transmitter, a very large array two dimensional sonar receiver, and a beamformer section transmits a series of sonar pings into an insonified volume of fluid at a rate greater than 5 pings per second, receives sonar signals reflected and scattered from objects in the insonified volume, and beamforms the reflected signals to provide a video presentation and/or to store the beamformed data for later use. The parameters controlling the sonar system are changed between pings to provide enhanced video imaging.

Abstract: A portion of a line from a line laying vessel to a touchdown support point on or near to the seabed is imaged with a 3 dimensional sonar imaging system to produce coordinates of a series of touchdown points using a time sequence of sonar images, and the time series of touchdown points is recorded.

Abstract: Reflected sonar signals arising from one or more possible unknown objects are distinguished according to a first criterion, and possible shapes each having a defined unique associated point are assigned each of the possible unknown objects. Then the three dimensional points are tracked by the sonar system.