Prof. dr. sc. Željko Šitum, dr. sc. Juraj Benić, Toni Fain, univ. bacc. ing., Pavao Kaštelan, univ. bacc. ing.; all University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture

Abstract:
This paper presents the design and practical realization of two mechatronic systems designed to float in the water. The paper first presents a remotely controlled pneumatically powered boat, as an example of ecological and unconventional vessels. The boat is constructed with a proper arrangement of components to ensure its better balance. The propeller is driven by an air motor that enables the propulsion of the boat. The actuator for steering is a three-position pneumatic cylinder that realizes the three positions of the rudder blade (left-center-right). The air supply to the actuators is controlled using a valve block and a microcontroller. The boat can be used to patrol waterways, monitor marine wildlife or conduct water quality tests. In the second part of the article, a remotely controlled underwater vehicle or a miniature submarine is presented. The body of the submarine is a watertight chamber containing four ballast tanks, a control unit and batteries. Two servo motors are used to fill and empty water from the ballast tanks, which allows the vessel to sink and surface. The submarine is steered by a servo motor that rotates the rudder blade, and a DC motor that drives the propeller. The microcontroller is used to control the direction of rotation of the motors and the angle of the boat’s rudder.

Keywords:
pneumatically powered boat, air motor, underwater vehicle, remote control, miniature submarine