The need to associate the collection of oceanographic data with the use of opportunity vessels, particularly the fishing fleet, has attracted growing interest in the development of underwater equipment or vehicles fitted with multi-parameter seawater probes. Thus, four digital models of undulating tow vehicles were developed, called U-Tow, using the software program SolidWorks, to be made from fiberglass and fitted with an electronic probe that continuously gathers oceanographie data on the ship's course, and details of the water column. The undulating system was conceived to be fully mechanical and adjustable, according to the requirements for collections performed under a wide variety of conditions stipulated by different opportunity vessels, without the need for specific training of the crew, or unnecessary occupation of space on the deck. The aim is to improve the different models presented (U-tow I to U-tow IV) in terms of their hydrodynamic, accessories for equipment protection, and ease of operation in terms of installing the probe inside the equipment.