Disclosed is a non-steel high strength data transmission cable having a strength member (5) and a core (1). The high strength data transmission cable includes a length of a core-cable (10), the length of core-cable (10) includes core (1) plus at least one fiber-optic conductor (2) that is: (i) disposed in a helical shape; and (ii) completely encased in a solid, flexible material. Also disclosed is a process for making a high strength data transmission cable. The high strength data transmission cable is capable of being wound on a winch under tensions and surging shocks experienced by a fishing trawler, and provides high quality data signal transmission and resolution so as to permit use for transmitting data during fish trawl operation from high-resolution sonars used to monitor fish caught.

A multipurpose portable or transportable selective fish capture system and no touch transport system is described that comprises an interconverting pontoon platform which can be adapted to include a solar and/or hydro electrical energy collection, conversion, storage and distribution system and to convert between a selective fish capture system and no touch fish transport system and an for emergency response for search and rescue or oil spill response support and oil spill collection and oil transport system.

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.

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.