Abstract: A method of controlling position of a trawl net is provided. The method may comprise: receiving, by a processor, a control input, wherein the control input comprises: (i) a selection of one of a plurality of position control modes, and (ii) a position control setpoint for the trawl net; receiving, by the processor, sensor data indicating a sensed position of the trawl net; generating, by the processor, a first trawl position control output based on the control input and the sensor data; determining, by the processor, a rate of change of bathymetry along a travel path of the trawl net; and in response to the rate of change of bathymetry meeting a threshold condition, generating a second trawl position control output by changing the one of the plurality of position control modes to another of the plurality of position control modes.

Abstract: A method of controlling position of a trawl net is provided. The method may comprise: receiving, by a processor, a control input, wherein the control input comprises: (i) a selection of one of a plurality of position control modes, and (ii) a position control setpoint for the trawl net; receiving, by the processor, sensor data indicating a sensed position of the trawl net; generating, by the processor, a first trawl position control output based on the control input and the sensor data; determining, by the processor, a rate of change of bathymetry along a travel path of the trawl net; and in response to the rate of change of bathymetry meeting a threshold condition, generating a second trawl position control output by changing the one of the plurality of position control modes to another of the plurality of position control modes.

Abstract: A method of controlling position of a trawl net is provided. The method may comprise: receiving, by a processor, a control input, wherein the control input comprises: (i) a selection of one of a plurality of position control modes, and (ii) a position control setpoint for the trawl net; receiving, by the processor, sensor data indicating a sensed position of the trawl net; and generating, by the processor, a trawl position control output based on the control input, the sensor data and predicted trawl net position data. The predicted trawl net position data may be generated by: defining, by the processor, a plurality of parameters; receiving, by the processor, input data comprising vessel speed data, tow line payout data, and a candidate drag coefficient value for the trawl net; and determining, by the processor, a tow angle based on the plurality of parameters and the input data.